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Sen M, Honavar SG, Bansal R, Sengupta S, Rao R, Kim U, Sharma M, Sachdev M, Grover AK, Surve A, Budharapu A, Ramadhin AK, Tripathi AK, Gupta A, Bhargava A, Sahu A, Khairnar A, Kochar A, Madhavani A, Shrivastava AK, Desai AK, Paul A, Ayyar A, Bhatnagar A, Singhal A, Nikose AS, Bhargava A, Tenagi AL, Kamble A, Nariani A, Patel B, Kashyap B, Dhawan B, Vohra B, Mandke C, Thrishulamurthy C, Sambare C, Sarkar D, Mankad DS, Maheshwari D, Lalwani D, Kanani D, Patel D, Manjandavida FP, Godhani F, Agarwal GA, Ravulaparthi G, Shilpa GV, Deshpande G, Thakkar H, Shah H, Ojha HR, Jani H, Gontia J, Mishrikotkar JP, Likhari K, Prajapati K, Porwal K, Koka K, Dharawat KS, Ramamurthy LB, Bhattacharyya M, Saini M, Christy MC, Das M, Hada M, Panchal M, Pandharpurkar M, Ali MO, Porwal M, Gangashetappa N, Mehrotra N, Bijlani N, Gajendragadkar N, Nagarkar NM, Modi P, Rewri P, Sao P, Patil PS, Giri P, Kapadia P, Yadav P, Bhagat P, Parekh R, Dyaberi R, Chauhan RS, Kaur R, Duvesh RK, Murthy R, Dandu RV, Kathiara R, Beri R, Pandit R, Rani RH, Gupta R, Pherwani R, Sapkal R, Mehta R, Tadepalli S, Fatima S, Karmarkar S, Patil SS, Shah S, Shah S, Shah S, Dubey S, Gandhi S, Kanakpur S, Mohan S, Bhomaj S, Kerkar S, Jariwala S, Sahu S, Tara S, Maru SK, Jhavar S, Sharma S, Gupta S, Kumari S, Das S, Menon S, Burkule S, Nisar SP, Kaliaperumal S, Rao S, Pakrasi S, Rathod S, Biradar SG, Kumar S, Dutt S, Bansal S, Ravani SA, Lohiya S, Rizvi SWA, Gokhale T, Lahane TP, Vukkadala T, Grover T, Bhesaniya T, Chawla U, Singh U, Une VL, Nandedkar V, Subramaniam V, Eswaran V, Chaudhary VN, Rangarajan V, Dehane V, Sahasrabudhe VM, Sowjanya Y, Tupkary Y, Phadke Y. Epidemiology, clinical profile, management, and outcome of COVID-19-associated rhino-orbital-cerebral mucormycosis in 2826 patients in India - Collaborative OPAI-IJO Study on Mucormycosis in COVID-19 (COSMIC), Report 1. Indian J Ophthalmol 2021; 69:1670-1692. [PMID: 34156034 PMCID: PMC8374756 DOI: 10.4103/ijo.ijo_1565_21] [Citation(s) in RCA: 201] [Impact Index Per Article: 67.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Revised: 06/06/2021] [Accepted: 06/07/2021] [Indexed: 12/15/2022] Open
Abstract
Purpose COVID-19-associated rhino-orbital-cerebral mucormycosis (ROCM) has reached epidemic proportion during India's second wave of COVID-19 pandemic, with several risk factors being implicated in its pathogenesis. This study aimed to determine the patient demographics, risk factors including comorbidities, and medications used to treat COVID-19, presenting symptoms and signs, and the outcome of management. Methods This was a retrospective, observational study of patients with COVID-19-associated ROCM managed or co-managed by ophthalmologists in India from January 1, 2020 to May 26, 2021. Results Of the 2826 patients, the states of Gujarat (22%) and Maharashtra (21%) reported the highest number of ROCM. The mean age of patients was 51.9 years with a male preponderance (71%). While 57% of the patients needed oxygen support for COVID-19 infection, 87% of the patients were treated with corticosteroids, (21% for > 10 days). Diabetes mellitus (DM) was present in 78% of all patients. Most of the cases showed onset of symptoms of ROCM between day 10 and day 15 from the diagnosis of COVID-19, 56% developed within 14 days after COVID-19 diagnosis, while 44% had delayed onset beyond 14 days. Orbit was involved in 72% of patients, with stage 3c forming the bulk (27%). Overall treatment included intravenous amphotericin B in 73%, functional endoscopic sinus surgery (FESS)/paranasal sinus (PNS) debridement in 56%, orbital exenteration in 15%, and both FESS/PNS debridement and orbital exenteration in 17%. Intraorbital injection of amphotericin B was administered in 22%. At final follow-up, mortality was 14%. Disease stage >3b had poorer prognosis. Paranasal sinus debridement and orbital exenteration reduced the mortality rate from 52% to 39% in patients with stage 4 disease with intracranial extension (p < 0.05). Conclusion : Corticosteroids and DM are the most important predisposing factors in the development of COVID-19-associated ROCM. COVID-19 patients must be followed up beyond recovery. Awareness of red flag symptoms and signs, high index of clinical suspicion, prompt diagnosis, and early initiation of treatment with amphotericin B, aggressive surgical debridement of the PNS, and orbital exenteration, where indicated, are essential for successful outcome.
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Affiliation(s)
| | | | | | | | - Raksha Rao
- Narayana Netralaya, Bengaluru, Karnataka, India
| | - Usha Kim
- Aravind Eye Care, Madurai, Tamil Nadu, India
| | | | | | - Ashok K Grover
- Department of Ophthalmology, Sir Ganga Ram Hospital and Vision Eye Centres, New Delhi, India
| | - Abhidnya Surve
- Department of Ophthalmology, Dr. Hedgewar Rugnalaya, Aurangabad, Maharashtra, India
| | - Abhishek Budharapu
- Department of Head and Neck Surgery, Apollo Cancer Hospital, Hyderabad, Telangana, India
| | - Abhishek K Ramadhin
- Department of Otorhinolaryngology, Dr Abhishek K. Ramadhin Hospital and Avyaan Research Centre, Ranchi, Jharkhand, India
| | | | - Adit Gupta
- Mumbai Eye Plastic Surgery, Maharashtra, India
| | - Aditya Bhargava
- Department of Otorhinolaryngology, Post Graduate Institute of Medical Sciences, Rohtak, Haryana, India
| | - Animesh Sahu
- Retina Speciality Hospital, Indore, Madhya Pradesh, India
| | - Anjali Khairnar
- Department of Ophthalmology, Shree Bhausaheb Hire Government Medical College, Dhule, Maharashtra, India
| | - Anju Kochar
- Department of Ophthalmology, Sardar Patel Medical College, Bikaner, Rajasthan, India
| | - Ankita Madhavani
- Department of Ophthalmology, Pandit Deendayal Upadhyay Medical College, Rajkot, Gujarat, India
| | - Ankur K Shrivastava
- Department of Ophthalmology, All India Institute of Medical Sciences, Raipur, Chhattisgarh, India
| | - Anuja K Desai
- Department of Ophthalmology, Kusum Dhirajlal Hospital, Ahmedabad, Gujarat, India
| | - Anujeet Paul
- Department of Ophthalmology, Mahatma Gandhi Medical College and Research Institute, Puducherry, India
| | | | - Aparna Bhatnagar
- Department of Ophthalmology, Apollo Specialty Hospitals, Chennai, Tamil Nadu, India
| | - Aparna Singhal
- Department of Ophthalmology, Maharaja Agrasen Medical College, Agroha, Haryana, India
| | - Archana Sunil Nikose
- Department of Ophthalmology, NKP Salve Institute of Medical Sciences and Research Centre, Nagpur, Maharashtra, India
| | - Arun Bhargava
- Retina Speciality Hospital, Indore, Madhya Pradesh, India
| | - Arvind L Tenagi
- Department of Ophthalmology, Jawaharlal Nehru Medical College, Karnataka Lingayat Education Academy of Higher Education and Research, Belagavi, Karnataka, India
| | - Ashish Kamble
- Department of Ophthalmology, Kingsway Hospital, Nagpur, Maharashtra, India
| | - Ashiyana Nariani
- Department of Ophthalmology, King Edward Memorial Hospital and Seth Gordhandas Sunderdas Medical College, Mumbai, Maharashtra, India
| | - Bhavin Patel
- Department of Otorhinolaryngology, Kiran Super Multi-Speciality Hospital, Surat, Gujarat, India
| | | | - Bodhraj Dhawan
- Department of Ophthalmology, Alexis Hospital, Nagpur, Maharashtra, India
| | - Busaraben Vohra
- Department of Ophthalmology, Medical College Baroda and Sir Sayajirao General Hospital, Vadodara, Gujarat, India
| | - Charuta Mandke
- Department of Ophthalmology, Hinduhridaysamrat Balasaheb Thackeray Medical College & Dr. R. N. Cooper Municipal Hospital, Mumbai, Maharashtra, India
| | - Chinmayee Thrishulamurthy
- Department of Ophthalmology, Bangalore Medical College and Research Institute, Bengaluru, Karnataka, India
| | - Chitra Sambare
- Department of Ophthalmology, Jehangir Hospital, Pune, Maharashtra, India
| | - Deepayan Sarkar
- Department of Ophthalmology, All India Institute of Medical Sciences, Bhopal, Madhya Pradesh, India
| | | | - Dhwani Maheshwari
- Department of Ophthalmology, Sir Sayajirao Gaekwad Hospital, Vadodra, Gujarat, India
| | | | - Dipti Kanani
- Department of Ophthalmology, Pandit Deendayal Upadhyay Medical College, Rajkot, Gujarat, India
| | - Diti Patel
- Department of Ophthalmology, Medical College Baroda and Sir Sayajirao General Hospital, Vadodara, Gujarat, India
| | | | - Frenali Godhani
- Department of Ophthalmology, Jagjivan Ram Railway Hospital, Mumbai, Maharashtra, India
| | - Garima Amol Agarwal
- M and J Western Regional Institute of Ophthalmology, Byramjee Jeejeebhoy Medical College, Ahmedabad, Gujarat, India
| | - Gayatri Ravulaparthi
- Department of Ophthalmology, Mamata Academy of Medical Sciences, Hyderabad, Telangana, India
| | | | | | - Hansa Thakkar
- M and J Western Regional Institute of Ophthalmology, Byramjee Jeejeebhoy Medical College, Ahmedabad, Gujarat, India
| | - Hardik Shah
- Department of Otorhinolaryngology, Kusum Dhirajlal Hospital, Ahmedabad, Gujarat, India
| | | | - Harsha Jani
- Department of Ophthalmology, Pramukh Swami Medical College, Karamsad, Gujarat, India
| | - Jyoti Gontia
- Department of Ophthalmology, Maharaja Yeshwantrao Hospital, Mahatma Gandhi Memorial Medical College, Indore, Madhya Pradesh, India
| | - Jyotika P Mishrikotkar
- Department of Ophthalmology, Mahatma Gandhi Mission Medical College and Hospital, Aurangabad, Maharashtra, India
| | | | - Kamini Prajapati
- M and J Western Regional Institute of Ophthalmology, Byramjee Jeejeebhoy Medical College, Ahmedabad, Gujarat, India
| | - Kavita Porwal
- Department of Ophthalmology, Convenient Hospitals Limited (CHL) – Hospitals, Indore, Madhya Pradesh, India
| | - Kirthi Koka
- Sankara Nethralaya, Chennai, Tamil Nadu, India
| | | | - Lakshmi B Ramamurthy
- Department of Ophthalmology, Karnataka Institute of Medical Sciences, Hubli, Karnataka, India
| | | | - Manorama Saini
- Department of Ophthalmology, Maharaja Agrasen Medical College, Agroha, Haryana, India
| | | | - Mausumi Das
- Department of Ophthalmology, Mahatma Gandhi Medical College and Research Institute, Puducherry, India
| | - Maya Hada
- Department of Ophthalmology, Sawai Man Singh Medical College, Jaipur, Rajasthan, India
| | - Mehul Panchal
- Department of Microbiology, Kiran Super Multi-Speciality Hospital, Surat, Gujarat, India
| | | | | | | | - Nagaraju Gangashetappa
- Department of Ophthalmology, Bangalore Medical College and Research Institute, Bengaluru, Karnataka, India
| | - Neelima Mehrotra
- Department of Ophthalmology, Shri Ram Murti Smarak Institute of Medical Sciences, Bareilly, Uttar Pradesh, India
| | - Neha Bijlani
- Vision Care & Research Centre, Bhopal, Madhya Pradesh, India
| | | | - Nitin M Nagarkar
- Department of Otorhinolaryngology, All India Institute of Medical Sciences, Raipur, Chhattisgarh, India
| | - Palak Modi
- M and J Western Regional Institute of Ophthalmology, Byramjee Jeejeebhoy Medical College, Ahmedabad, Gujarat, India
| | - Parveen Rewri
- Department of Ophthalmology, Maharaja Agrasen Medical College, Agroha, Haryana, India
| | - Piyushi Sao
- Department of Ophthalmology, Shri Mallanagouda Basanagouda Patil Medical College, BLDE University, Vijayapura, Karnataka, India
| | - Prajakta Salunkhe Patil
- Department of Ophthalmology, Krishna Institute of Medical Sciences, Karad, Maharashtra, India
| | - Pramod Giri
- Max Vision Eye Hospital, Nagpur, Maharashtra, India
| | - Priti Kapadia
- Department of Ophthalmology, Government Medical College, Surat, Gujarat, India
| | - Priti Yadav
- Department of Ophthalmology, Maharaja Yeshwantrao Hospital, Mahatma Gandhi Memorial Medical College, Indore, Madhya Pradesh, India
| | - Purvi Bhagat
- M and J Western Regional Institute of Ophthalmology, Byramjee Jeejeebhoy Medical College, Ahmedabad, Gujarat, India
| | - Ragini Parekh
- Department of Ophthalmology, Grant Medical College and Sir Jamshedjee Jeejeebhoy Group of Hospitals, Mumbai, Maharashtra, India
| | - Rajashekhar Dyaberi
- Department of Ophthalmology, Karnataka Institute of Medical Sciences, Hubli, Karnataka, India
| | - Rajender Singh Chauhan
- Regional Institute of Ophthalmology, Post Graduate Institute of Medical Sciences, Rohtak, Haryana, India
| | - Rajwinder Kaur
- Department of Ophthalmology, Adesh Institute of Medical Sciences and Research, Bhatinda, Punjab, India
| | - Ram Kishan Duvesh
- Department of Ophthalmology, Vardhaman Mahavir Medical College and Safdarjung Hospital, New Delhi, India
| | | | - Ravi Varma Dandu
- Department of Neuroradiology, Citi Neuro Centre, Hyderabad, Telangana, India
| | - Ravija Kathiara
- M and J Western Regional Institute of Ophthalmology, Byramjee Jeejeebhoy Medical College, Ahmedabad, Gujarat, India
| | - Renu Beri
- Department of Ophthalmology, Civil Hospital Ambala Cantonment, Haryana, India
| | - Rinal Pandit
- Department of Ophthalmology, Choithram Hospital & Research Centre, Indore, Madhya Pradesh, India
| | - Rita Hepsi Rani
- Department of Ophthalmology, Tirunelveli Medical College, Tirunelveli, Tamil Nadu, India
| | | | - Ruchi Pherwani
- Department of Ophthalmology, SMBT Institute of Medical Sciences and Research Centre, Nashik, Maharashtra, India
| | - Rujuta Sapkal
- Department of Ophthalmology, Mahatma Gandhi Mission Medical College and Hospital, Aurangabad, Maharashtra, India
| | - Rupa Mehta
- Department of Otorhinolaryngology, All India Institute of Medical Sciences, Raipur, Chhattisgarh, India
| | - Sameeksha Tadepalli
- Advanced Eye Centre, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Samra Fatima
- Sarojini Devi Eye Hospital, Hyderabad, Telangana, India
| | - Sandeep Karmarkar
- Department of Otorhinolaryngology, Ruby Hall Clinic, Pune, Maharashtra, India
| | | | - Sanjana Shah
- Department of Ophthalmology, Medical College Baroda and Sir Sayajirao General Hospital, Vadodara, Gujarat, India
| | - Sankit Shah
- Department of Ophthalmology, Kiran Super Multi-Speciality Hospital, Surat, Gujarat, India
| | - Sapan Shah
- Department of Ophthalmology, Kusum Dhirajlal Hospital, Ahmedabad, Gujarat, India
| | - Sarika Dubey
- Department of Ophthalmology, Sawai Man Singh Medical College, Jaipur, Rajasthan, India
| | | | - Savitha Kanakpur
- Department of Ophthalmology, Karnataka Institute of Medical Sciences, Hubli, Karnataka, India
| | - Shalini Mohan
- Department of Ophthalmology, Ganesh Shankar Vidyarthi Memorial Medical College, Kanpur, Uttar Pradesh, India
| | | | - Sheela Kerkar
- Department of Ophthalmology, King Edward Memorial Hospital and Seth Gordhandas Sunderdas Medical College, Mumbai, Maharashtra, India
| | - Shivani Jariwala
- Department of Ophthalmology, Government Medical College, Surat, Gujarat, India
| | - Shivati Sahu
- Department of Ophthalmology, Maharaja Yeshwantrao Hospital, Mahatma Gandhi Memorial Medical College, Indore, Madhya Pradesh, India
| | | | - Shruti Kochar Maru
- Department of Ophthalmology, Convenient Hospitals Limited (CHL) – Hospitals, Indore, Madhya Pradesh, India
| | - Shubha Jhavar
- Department of Ophthalmology, Government Medical College, Aurangabad, Maharashtra, India
| | - Shubhda Sharma
- Department of Ophthalmology, Medanta - The Medicity, Gurugram, Haryana, India
| | - Shweta Gupta
- Sankara Eye Foundation, Indore, Madhya Pradesh, India
| | - Shwetha Kumari
- Department of Ophthalmology, Bowring and Lady Curzon Hospital, Bangalore Medical College and Research Institute, Bengaluru, Karnataka, India
| | - Sima Das
- Dr. Shroff Charity Eye Hospital, New Delhi, India
| | - Smita Menon
- Department of Ophthalmology, King Edward Memorial Hospital and Seth Gordhandas Sunderdas Medical College, Mumbai, Maharashtra, India
| | - Snehal Burkule
- Department of Ophthalmology, Dr. Shankarrao Chavan Government Medical College, Nanded, Maharashtra, India
| | | | - Subashini Kaliaperumal
- Department of Ophthalmology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
| | - Subramanya Rao
- Department of Otorhinolaryngology, Rangadore Memorial Hospital, Bengaluru, Karnataka, India
| | - Sudipto Pakrasi
- Department of Ophthalmology, Medanta - The Medicity, Gurugram, Haryana, India
| | - Sujatha Rathod
- Department of Ophthalmology, Bangalore Medical College and Research Institute, Bengaluru, Karnataka, India
| | - Sunil G Biradar
- Department of Ophthalmology, Shri Mallanagouda Basanagouda Patil Medical College, BLDE University, Vijayapura, Karnataka, India
| | - Suresh Kumar
- Department of Ophthalmology, Government Medical College, Chandigarh, India
| | - Susheen Dutt
- Department of Otorhinolaryngology, Rangadore Memorial Hospital, Bengaluru, Karnataka, India
| | - Svati Bansal
- Department of Ophthalmology, Medanta - The Medicity, Gurugram, Haryana, India
| | - Swati Amulbhai Ravani
- M and J Western Regional Institute of Ophthalmology, Byramjee Jeejeebhoy Medical College, Ahmedabad, Gujarat, India
| | - Sweta Lohiya
- Department of Otorhinolaryngology, Kingsway Hospital, Nagpur, Maharashtra, India
| | - Syed Wajahat Ali Rizvi
- Department of Ophthalmology, Jawaharlal Nehru Medical College, Aligarh Muslim University, Aligarh, Uttar Pradesh, India
| | - Tanmay Gokhale
- Department of Ophthalmology, Jawaharlal Institute of Postgraduate Medical Education and Research, Puducherry, India
| | - Tatyarao P Lahane
- Department of Ophthalmology, Grant Medical College and Sir Jamshedjee Jeejeebhoy Group of Hospitals, Mumbai, Maharashtra, India
| | | | - Triveni Grover
- Department of Ophthalmology, Fortis Hospital, Shalimar Bagh, New Delhi, India
| | - Trupti Bhesaniya
- Department of Ophthalmology, Government Medical College, Surat, Gujarat, India
| | - Urmil Chawla
- Regional Institute of Ophthalmology, Post Graduate Institute of Medical Sciences, Rohtak, Haryana, India
| | - Usha Singh
- Advanced Eye Centre, Post Graduate Institute of Medical Education and Research, Chandigarh, India
| | - Vaishali L Une
- Department of Ophthalmology, Shree Bhausaheb Hire Government Medical College, Dhule, Maharashtra, India
| | - Varsha Nandedkar
- Department of Ophthalmology, Government Medical College, Aurangabad, Maharashtra, India
| | | | - Vidya Eswaran
- Department of Ophthalmology, Bowring and Lady Curzon Hospital, Bangalore Medical College and Research Institute, Bengaluru, Karnataka, India
| | - Vidya Nair Chaudhary
- Department of Ophthalmology, Aakash Healthcare Super-Specialty Hospital, New Delhi, India
| | | | - Vipin Dehane
- Department of Oral and Maxillofacial Surgery, Kingsway Hospital, Nagpur, Maharashtra, India
| | - Vivek M Sahasrabudhe
- Department of Ophthalmology, Dr. Shankarrao Chavan Government Medical College, Nanded, Maharashtra, India
| | | | - Yashaswini Tupkary
- Department of Medicine, Dr. Hedgewar Rugnalaya, Aurangabad, Maharashtra, India
| | - Yogita Phadke
- Department of Ophthalmology, Mahatma Gandhi Mission Medical College and Hospital, Aurangabad, Maharashtra, India
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Subramaniam V, Ganapathy S, Paruchuri S. Ventriculo-ureteric shunts, the last resort in complicated shunt patients. Interdisciplinary Neurosurgery 2020. [DOI: 10.1016/j.inat.2020.100805] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Subramaniam V, Thevanayagam H. Salmonella enteritidis in a Green Anaconda (Eunectes mutinous): A case study in Peninsular Malaysia. Int J Infect Dis 2020. [DOI: 10.1016/j.ijid.2020.09.1395] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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Spitz JA, Chao AH, Peterson DM, Subramaniam V, Prakash S, Skoracki RJ. BIOIMPEDANCE SPECTROSCOPY IS NOT ASSOCIATED WITH A CLINICAL DIAGNOSIS OF BREAST CANCER-RELATED LYMPHEDEMA. Lymphology 2020. [DOI: 10.2458/lymph.4634] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
The objective of this study was to evaluate the accuracy of bioimpedance spectroscopy measurements (L-Dex) in the diagnosis of breast cancer-related lymphedema. A retrospective review of a prospectively maintained database was performed of all patients that underwent surgical treatment for breast cancer at a tertiary medical center. Patients who had preoperative and postoperative evaluation for possible lymphedema by limb circumference measurements and bioimpedance were eligible for inclusion in the study. No significant demographic differences were found between the group of patients clinically diagnosed with lymphedema (N=134) and those without a clinical diagnosis of lymphedema (N=261). The ability of bioimpedance to diagnose lymphedema based on the manufacturer's criteria demonstrated low sensitivity, which was 7.5% when lymphedema was defined as an absolute L-Dex value greater than 10, and 24.6% when defined as a relative change of >10 between preoperative and postoperative measurements. This corresponded with a positive predictive value of 61-71% and a negative predictive value of 67-70%. We are unable to recommend the use of bioimpedance as a screening tool or for measurement of breast cancer-related lymphedema.
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Spitz JA, Chao A, Peterson DM, Subramaniam V, Prakash S, Skoracki RJ. Bioimpedance spectroscopy is not associated with a clinical diagnosis of breast cancer-related lymphedema. Lymphology 2019; 52:134-142. [PMID: 31874125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The objective of this study was to evaluate the accuracy of bioimpedance spectroscopy measurements (L-Dex) in the diagnosis of breast cancer-related lymphedema. A retrospective review of a prospectively maintained database was performed of all patients that underwent surgical treatment for breast cancer at a tertiary medical center. Patients who had preoperative and postoperative evaluation for possible lymphedema by limb circumference measurements and bioimpedance were eligible for inclusion in the study. No significant demographic differences were found between the group of patients clinically diagnosed with lymphedema (N=134) and those without a clinical diagnosis of lymphedema (N=261). The ability of bioimpedance to diagnose lymphedema based on the manufacturer's criteria demonstrated low sensitivity, which was 7.5% when lymphedema was defined as an absolute L-Dex value greater than 10, and 24.6% when defined as a relative change of >10 between preoperative and postoperative measurements. This corresponded with a positive predictive value of 61-71% and a negative predictive value of 67-70%. We are unable to recommend the use of bioimpedance as a screening tool or for measurement of breast cancer-related lymphedema.
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Affiliation(s)
- J A Spitz
- Department of Plastic Surgery, The Ohio State University, Columbus, Ohio, USA
| | - Albert Chao
- Department of Plastic Surgery, The Ohio State University, Columbus, Ohio, USA
| | - D M Peterson
- Department of Surgery, Penn State Health Milton S. Hershey Medical Center, Hershey, Pennsylvania, USA
| | - V Subramaniam
- Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio, USA
| | - S Prakash
- Department of Mechanical and Aerospace Engineering, The Ohio State University, Columbus, Ohio, USA
| | - R J Skoracki
- Department of Plastic Surgery, The Ohio State University, Columbus, Ohio, USA
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Hassink GC, Raiss CC, Segers-Nolten IMJ, van Wezel RJA, Subramaniam V, le Feber J, Claessens MMAE. Exogenous α-synuclein hinders synaptic communication in cultured cortical primary rat neurons. PLoS One 2018; 13:e0193763. [PMID: 29565978 PMCID: PMC5863964 DOI: 10.1371/journal.pone.0193763] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Accepted: 02/17/2018] [Indexed: 12/25/2022] Open
Abstract
Amyloid aggregates of the protein α-synuclein (αS) called Lewy Bodies (LB) and Lewy Neurites (LN) are the pathological hallmark of Parkinson's disease (PD) and other synucleinopathies. We have previously shown that high extracellular αS concentrations can be toxic to cells and that neurons take up αS. Here we aimed to get more insight into the toxicity mechanism associated with high extracellular αS concentrations (50-100 μM). High extracellular αS concentrations resulted in a reduction of the firing rate of the neuronal network by disrupting synaptic transmission, while the neuronal ability to fire action potentials was still intact. Furthermore, many cells developed αS deposits larger than 500 nm within five days, but otherwise appeared healthy. Synaptic dysfunction clearly occurred before the establishment of large intracellular deposits and neuronal death, suggesting that an excessive extracellular αS concentration caused synaptic failure and which later possibly contributed to neuronal death.
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Affiliation(s)
- G. C. Hassink
- Clinical Neurophysiology, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Postbus, Enschede, the Netherlands
- Biomedical Signal and Systems, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Postbus, Enschede, the Netherlands
| | - C. C. Raiss
- Nanobiophysics Group, MESA+ Institute for Nanotechnology, University of Twente, Postbus, Enschede, the Netherlands
| | - I. M. J. Segers-Nolten
- Nanobiophysics Group, MESA+ Institute for Nanotechnology, University of Twente, Postbus, Enschede, the Netherlands
| | - R. J. A. van Wezel
- Biomedical Signal and Systems, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Postbus, Enschede, the Netherlands
- Biophysics, Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, Postbus, The Netherlands
| | - V. Subramaniam
- Nanobiophysics Group, MESA+ Institute for Nanotechnology, University of Twente, Postbus, Enschede, the Netherlands
| | - J. le Feber
- Clinical Neurophysiology, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Postbus, Enschede, the Netherlands
- Biomedical Signal and Systems, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Postbus, Enschede, the Netherlands
- * E-mail:
| | - M. M. A. E. Claessens
- Clinical Neurophysiology, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Postbus, Enschede, the Netherlands
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Wasserberg D, Cabanas-Danés J, Subramaniam V, Huskens J, Jonkheijm P. Orthogonal supramolecular protein assembly on patterned bifunctional surfaces. Chem Commun (Camb) 2018; 54:1615-1618. [DOI: 10.1039/c7cc09808a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
Selective dual protein assembly achieved using metal–ion and host–guest interactions with fluorescent proteins, modified with binding tags, by controlling opposing supramolecular interactions.
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Affiliation(s)
- D. Wasserberg
- Bioinspired Molecular Engineering Laboratory
- MIRA Biomedical Technology and Technical Medicine Institute
- University of Twente
- 7500 AE Enschede
- The Netherlands
| | - J. Cabanas-Danés
- Bioinspired Molecular Engineering Laboratory
- MIRA Biomedical Technology and Technical Medicine Institute
- University of Twente
- 7500 AE Enschede
- The Netherlands
| | - V. Subramaniam
- Nanobiophysics Group
- MESA+ Institute for Nanotechnology and MIRA Biomedical Technology and Technical Medicine Institute
- University of Twente
- 7500 AE Enschede
- The Netherlands
| | - J. Huskens
- Molecular Nanofabrication Group
- MESA+ Institute for Nanotechnology
- University of Twente
- 7500 AE Enschede
- The Netherlands
| | - P. Jonkheijm
- Bioinspired Molecular Engineering Laboratory
- MIRA Biomedical Technology and Technical Medicine Institute
- University of Twente
- 7500 AE Enschede
- The Netherlands
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Smith R, Brooke D, Kipps C, Skaria B, Subramaniam V. A case of recurrent swimming-induced pulmonary edema in a triathlete: the need for awareness. Scand J Med Sci Sports 2016; 27:1130-1135. [PMID: 27485572 DOI: 10.1111/sms.12736] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/29/2016] [Indexed: 12/28/2022]
Abstract
This report discusses a rare case of a 55-year-old female triathlete who developed recurrent episodes of swimming-induced pulmonary edema (SIPE). She had two hospital admissions with pulmonary edema after developing breathlessness while swimming, including a near-drowning experience in an open water swim. With increasing popularity of triathlon and open water sports, this case highlights the importance of a greater awareness of SIPE among health professionals, event organizers, and athletes. This report explores the previous reported cases in triathletes and those who have suffered recurrent episodes. It is paramount that an accurate diagnosis is made as these individuals may be at an increased risk of future life-threatening episodes.
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Affiliation(s)
- R Smith
- Department of Sport and Exercise Medicine, Nuffield Orthopaedic Centre, Oxford University Hospitals NHS Trust, Oxford, UK
| | - D Brooke
- Frimley Park Hospital NHS Foundation Trust, Surrey, UK
| | - C Kipps
- Institute of Sport, Exercise and Health, Division of Surgery and Interventional Sciences, University College London, London, UK
| | - B Skaria
- Department of Cardiology, Solihull Hospital, Heart of England NHS Trust, Birmingham, UK
| | - V Subramaniam
- Department of Cardiology, Solihull Hospital, Heart of England NHS Trust, Birmingham, UK
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Grayson P, Carmona-Rivera C, Graf J, Irizarry-Caro J, Phillips K, Preston K, Purmalek M, Subramaniam V, Thompson P, Waldman M, Kaplan M. OP0054 Neuroimmunomodulation of Neutrophils as A Novel Mechanism of Levamisole-Induced Vasculitis. Ann Rheum Dis 2016. [DOI: 10.1136/annrheumdis-2016-eular.2963] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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10
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Janakiram TN, Sagar S, Sharma SB, Subramaniam V. Primary Mucoepidermoid Carcinoma of the Lacrimal Sac - a Case Report and Literature Review. Klin Onkol 2016; 29:291-294. [PMID: 27534787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
BACKGROUND Lacrimal sac tumors are very rare and are often missed because patients present with features consistent with chronic dacryocystitis. Squamous cell carcinoma is the common-est lacrimal sac malignancy. Although primary mucoepidermoid carcinomas of the lacrimal sac are rare, they are locally aggressive. Furthermore, their proximity to vital structures and the skull base makes them potentially life-threatening. Multidisciplinary management is required, and wide excision followed by chemoradiation is the recommended treatment. CASE Here, we report a 65-year-old male who presented with watering eyes and a mass in the region of the medial canthus. A dia-gnosis of primary mucoepidermoid carcinoma of the lacrimal sac was made, and the case was managed successfully with radical surgery and reconstruction. The tumor was resected using the extended Lynch-Howarth incision and the resulting defect was reconstructed using a forehead flap. Histopathological examination of the excised specimen revealed mucoepidermoid carcinoma. Immunohistochemical analysis revealed that the speci-men was positive for epithelial growth factor receptor and Ki-67 protein. The patient was referred for post-operative chemoradiation. The literature is reviewed and pathological features, including immunohistochemistry are discussed. CONCLUSION Primary mucoepidermoid carcinoma of the lacrimal sac is a rare, locally aggressive tumor that is often mistaken for dacryocystitis. The treatment of choice is radical surgery followed by chemoradiation. KEY WORDS lacrimal sac - mucoepidermoid carcinoma - epithelial growth factor receptor - Ki-67 protein.
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Molenaar R, Prangsma JC, van der Werf KO, Bennink ML, Blum C, Subramaniam V. Microcantilever based distance control between a probe and a surface. Rev Sci Instrum 2015; 86:063706. [PMID: 26133843 DOI: 10.1063/1.4922885] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
We demonstrate a method to control the distance between a custom probe and a sample on a μm to nm scale. The method relies on the closed-loop feedback on the angular deflection of an in-contact AFM microcantilever. High performance in stability and accuracy is achieved in this method by taking advantage of the small mechanical feedback path between surface and probe. We describe how internal error sources that find their origin in the microcantilever and feedback can be minimized to achieve an accurate and precise control up to 3 nm. In particular, we investigated how hysteresis effects in the feedback caused by friction forces between tip and substrate can be minimized. By applying a short calibration procedure, distance control from contact to several micrometers probe-sample distance can be obtained with an absolute nanometer-scale accuracy. The method presented is compatible with any probe that can be fixed on a microcantilever chip and can be easily built into existing AFM systems.
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Affiliation(s)
- R Molenaar
- Nanobiophysics Group, MESA+ Institute for Nanotechnology and MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands
| | - J C Prangsma
- Nanobiophysics Group, MESA+ Institute for Nanotechnology and MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands
| | - K O van der Werf
- Nanobiophysics Group, MESA+ Institute for Nanotechnology and MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands
| | - M L Bennink
- Nanobiophysics Group, MESA+ Institute for Nanotechnology and MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands
| | - C Blum
- Nanobiophysics Group, MESA+ Institute for Nanotechnology and MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands
| | - V Subramaniam
- Nanobiophysics Group, MESA+ Institute for Nanotechnology and MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, P.O. Box 217, 7500AE Enschede, The Netherlands
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Abstract
We design and test an octopus-inspired flexible hull robot that demonstrates outstanding fast-starting performance. The robot is hyper-inflated with water, and then rapidly deflates to expel the fluid so as to power the escape maneuver. Using this robot we verify for the first time in laboratory testing that rapid size-change can substantially reduce separation in bluff bodies traveling several body lengths, and recover fluid energy which can be employed to improve the propulsive performance. The robot is found to experience speeds over ten body lengths per second, exceeding that of a similarly propelled optimally streamlined rigid rocket. The peak net thrust force on the robot is more than 2.6 times that on an optimal rigid body performing the same maneuver, experimentally demonstrating large energy recovery and enabling acceleration greater than 14 body lengths per second squared. Finally, over 53% of the available energy is converted into payload kinetic energy, a performance that exceeds the estimated energy conversion efficiency of fast-starting fish. The Reynolds number based on final speed and robot length is [Formula: see text]. We use the experimental data to establish a fundamental deflation scaling parameter [Formula: see text] which characterizes the mechanisms of flow control via shape change. Based on this scaling parameter, we find that the fast-starting performance improves with increasing size.
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Affiliation(s)
- G D Weymouth
- Southampton Marine and Maritime Institute, University of Southampton, Southampton SO17 1BJ, UK
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Shekhar S, Cambi A, Figdor CG, Subramaniam V, Kanger JS. A method for spatially resolved local intracellular mechanochemical sensing and organelle manipulation. Biophys J 2013; 103:395-404. [PMID: 22947855 DOI: 10.1016/j.bpj.2012.06.010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 06/01/2012] [Accepted: 06/04/2012] [Indexed: 11/16/2022] Open
Abstract
Because both the chemical and mechanical properties of living cells play crucial functional roles, there is a strong need for biophysical methods to address these properties simultaneously. Here we present a novel (to our knowledge) approach to measure local intracellular micromechanical and chemical properties using a hybrid magnetic chemical biosensor. We coupled a fluorescent dye, which serves as a chemical sensor, to a magnetic particle that is used for measurement of the viscoelastic environment by studying the response of the particle to magnetic force pulses. As a demonstration of the potential of this approach, we applied the method to study the process of phagocytosis, wherein cytoskeletal reorganization occurs in parallel with acidification of the phagosome. During this process, we measured the shear modulus and viscosity of the phagosomal environment concurrently with the phagosomal pH. We found that it is possible to manipulate phagocytosis by stalling the centripetal movement of the phagosome using magnetic force. Our results suggest that preventing centripetal phagosomal transport delays the onset of acidification. To our knowledge, this is the first report of manipulation of intracellular phagosomal transport without interfering with the underlying motor proteins or cytoskeletal network through biochemical methods.
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Affiliation(s)
- S Shekhar
- Department of Nanobiophysics, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - A Cambi
- Department of Nanobiophysics, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands; Department of Tumor Immunology, Nijmegen Centre for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - C G Figdor
- Department of Tumor Immunology, Nijmegen Centre for Molecular Life Sciences, Radboud University, Nijmegen, The Netherlands
| | - V Subramaniam
- Department of Nanobiophysics, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands
| | - J S Kanger
- Department of Nanobiophysics, MIRA Institute for Biomedical Technology and Technical Medicine, University of Twente, Enschede, The Netherlands.
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Abstract
Amyloid fibrils are traditionally associated with neurodegenerative diseases like Alzheimer's disease, Parkinson's disease or Creutzfeldt-Jakob disease. However, the ability to form amyloid fibrils appears to be a more generic property of proteins. While disease-related, or pathological, amyloid fibrils are relevant for understanding the pathology and course of the disease, functional amyloids are involved, for example, in the exceptionally strong adhesive properties of natural adhesives. Amyloid fibrils are thus becoming increasingly interesting as versatile nanobiomaterials for applications in biotechnology. In the last decade a number of studies have reported on the intriguing mechanical characteristics of amyloid fibrils. In most of these studies atomic force microscopy (AFM) and atomic force spectroscopy play a central role. AFM techniques make it possible to probe, at nanometer length scales, and with exquisite control over the applied forces, biological samples in different environmental conditions. In this review we describe the different AFM techniques used for probing mechanical properties of single amyloid fibrils on the nanoscale. An overview is given of the existing mechanical studies on amyloid. We discuss the difficulties encountered with respect to the small fibril sizes and polymorphic behavior of amyloid fibrils. In particular, the different conformational packing of monomers within the fibrils leads to a heterogeneity in mechanical properties. We conclude with a brief outlook on how our knowledge of these mechanical properties of the amyloid fibrils can be exploited in the construction of nanomaterials from amyloid fibrils.
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Affiliation(s)
- K K M Sweers
- Nanobiophysics, MESA+ Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands.
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15
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Hoang H, Tong H, Segers-Nolten I, Tas N, Subramaniam V, Elwenspoek M. Wafer-scale thin encapsulated two-dimensional nanochannels and its application toward visualization of single molecules. J Colloid Interface Sci 2012; 367:455-9. [DOI: 10.1016/j.jcis.2011.10.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2011] [Revised: 09/26/2011] [Accepted: 10/01/2011] [Indexed: 10/16/2022]
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16
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Wasserberg D, Steentjes T, Stopel MHW, Huskens J, Blum C, Subramaniam V, Jonkheijm P. Patterning perylenes on surfaces using thiol–ene chemistry. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm32610h] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
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Mathew G, Subramaniam V, Sukumaran S, Baghi P. 3618 POSTER Multi-disciplinary Meetings for Linking Cancer Care Centres in Rural Australia – Results From a Clinical Practice Improvement Project. Eur J Cancer 2011. [DOI: 10.1016/s0959-8049(11)71215-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Hoang HT, Segers-Nolten IM, Tas NR, van Honschoten JW, Subramaniam V, Elwenspoek MC. Analysis of single quantum-dot mobility inside 1D nanochannel devices. Nanotechnology 2011; 22:275201. [PMID: 21597152 DOI: 10.1088/0957-4484/22/27/275201] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
We visualized individual quantum dots using a combination of a confining nanochannel and an ultra-sensitive microscope system, equipped with a high numerical aperture lens and a highly sensitive camera. The diffusion coefficients of the confined quantum dots were determined from the experimentally recorded trajectories according to the classical diffusion theory for Brownian motion in two dimensions. The calculated diffusion coefficients were three times smaller than those in bulk solution. These observations confirm and extend the results of Eichmann et al (2008 Langmuir 24 714-21) to smaller particle diameters and more narrow confinement. A detailed analysis shows that the observed reduction in mobility cannot be explained by conventional hydrodynamic theory.
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Affiliation(s)
- H T Hoang
- Transducers Science and Technology Group, MESA+ Research Institute for Nanotechnology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands.
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Subramaniam V, Kumar P, Thahir M. Mucoepidermoid carcinoma of a nasal cavity--a rare tumour. Klin Onkol 2010; 23:354-357. [PMID: 21058529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
BACKGROUNDS Mucoepidermoid tumours arise from the ductal cells of the salivary glands, most commonly the parotid. The occurrence of these tumours in the mucus glands of the air passages is extremely rare. They are very aggressive tumours with poor prognosis. CASE A case of nasal mucoepidermoid carcinoma with probable origin from the middle turbinate is reported. CONCLUSION Nasal mucoepidermoid carcinomas are extremely rare. They usually present with symptoms similar to sinusitis. When dealing with a recurrent/aggressive tumour in the ethmoids, the possibility of mucoepidermoid carcinoma can be considered in the differential diagnosis. They are aggressive tumours with a poor prognosis.
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Affiliation(s)
- V Subramaniam
- Department of Otorhinolaryngology, Yenepoya Medical College, Yenepoya University, Deralakatte, Mangalore, Karnataka, India.
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van Rooijen B, van Leijenhorst-Groener K, Claessens M, Subramaniam V. Tryptophan Fluorescence Reveals Structural Features of α-Synuclein Oligomers. J Mol Biol 2009; 394:826-33. [DOI: 10.1016/j.jmb.2009.10.021] [Citation(s) in RCA: 70] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2009] [Revised: 10/02/2009] [Accepted: 10/12/2009] [Indexed: 10/20/2022]
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Te Velde EA, Veerman T, Subramaniam V, Ruers T. The use of fluorescent dyes and probes in surgical oncology. Eur J Surg Oncol 2009; 36:6-15. [PMID: 19926438 DOI: 10.1016/j.ejso.2009.10.014] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2009] [Revised: 10/16/2009] [Accepted: 10/22/2009] [Indexed: 01/09/2023] Open
Abstract
AIMS AND BACKGROUND Improved visualization of surgical targets inside of the patient helps to improve radical resection of the tumor while sparing healthy surrounding tissue. In order to achieve an image, optical contrast must be generated by properties intrinsic to the tissue, or require the attachment of special visualization labels to the tumor. In this overview the current status of the clinical use of fluorescent dyes and probes are reviewed. METHODS In this review, all experimental and clinical studies concerning fluorescent imaging were included. In addition, in the search for the optimal fluorescent imaging modality, all characteristics of a fluorescent dye were described. FINDINGS AND CONCLUSIONS Although the technique of imaging through fluorescence sounds promising and several animal models show efficacy, official approval of these agents for further clinical evaluation, is eagerly awaited.
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Affiliation(s)
- E A Te Velde
- Department of Surgical Oncology, The Netherlands Cancer Institute, Antoni van Leeuwenhoek Hospital, Amsterdam, The Netherlands
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22
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Murade CU, Subramaniam V, Otto C, Bennink ML. Interaction of oxazole yellow dyes with DNA studied with hybrid optical tweezers and fluorescence microscopy. Biophys J 2009; 97:835-43. [PMID: 19651041 DOI: 10.1016/j.bpj.2009.05.024] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2008] [Revised: 04/18/2009] [Accepted: 05/07/2009] [Indexed: 10/20/2022] Open
Abstract
We have integrated single molecule fluorescence microscopy imaging into an optical tweezers set-up and studied the force extension behavior of individual DNA molecules in the presence of various YOYO-1 and YO-PRO-1 concentrations. The fluorescence modality was used to record fluorescent images during the stretching and relaxation cycle. Force extension curves recorded in the presence of either dye did not show the overstretching transition that is characteristic for bare DNA. Using the modified wormlike chain model to curve-fit the force extension data revealed a contour length increase of 6% and 30%, respectively, in the presence of YO-PRO-1 and YOYO-1 at 100 nM. The fluorescence images recorded simultaneously showed that the number of bound dye molecules increased as the DNA molecule was stretched and decreased again as the force on the complex was lowered. The binding constants and binding site sizes for YO-PRO-1 and YOYO-1 were determined as a function of the force. The rate of YO-PRO-1 binding and unbinding was found to be 2 orders of magnitude larger than that for YOYO-1. A kinetic model is proposed to explain this observation.
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Affiliation(s)
- C U Murade
- Department of Biophysical Engineering and MESA+ Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, 7500 AE Enschede, The Netherlands
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23
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Volkova KD, Kovalska VB, Segers-Nolten GM, Veldhuis G, Subramaniam V, Yarmoluk SM. Explorations of the application of cyanine dyes for quantitative α-synuclein detection. Biotech Histochem 2009; 84:55-61. [DOI: 10.1080/10520290902798799] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022] Open
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Volkova K, Kovalska V, Balanda A, Losytskyy M, Golub A, Vermeij R, Subramaniam V, Tolmachev O, Yarmoluk S. Specific fluorescent detection of fibrillar α-synuclein using mono- and trimethine cyanine dyes. Bioorg Med Chem 2008; 16:1452-9. [DOI: 10.1016/j.bmc.2007.10.051] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2007] [Revised: 10/03/2007] [Accepted: 10/17/2007] [Indexed: 10/22/2022]
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25
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Volkova KD, Kovalska VB, Balanda AO, Vermeij RJ, Subramaniam V, Slominskii YL, Yarmoluk SM. Cyanine dye–protein interactions: Looking for fluorescent probes for amyloid structures. ACTA ACUST UNITED AC 2007; 70:727-33. [PMID: 17467807 DOI: 10.1016/j.jbbm.2007.03.008] [Citation(s) in RCA: 60] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2007] [Revised: 03/20/2007] [Accepted: 03/21/2007] [Indexed: 11/24/2022]
Abstract
We ascertained the ability to detect fibrillar beta-lactoglobulin (BLG) of a series of mono-, tri-, penta-, and heptamethinecyanines based on benzothiazole and benzimidazole heterocycles, and of benzothiazole squaraine. Fluorescence properties of these cyanine dyes were measured in the unbound state and in the presence of monomeric and fibrillar BLG and compared with those for the commercially available benzothiazole dye Thioflavin T. The correlation between the chemical nature of the dye molecules and the ability of dyes to bind aggregated proteins was established. We found that meso-substituted cyanines with amino substituents in heterocycle in contrast to the corresponding unsubstituted dyes have a binding preference to fibrillar BLG and a noticeable fluorescence response in the presence of the aggregated protein. For the squaraines and benzimidazole penthamethinecyanines studied, fluorescence emission increased both in the presence of native and fibrillar protein. The trimethinecyanines T-49 and SH-516 exhibit specifically increased fluorescence in the presence of fibrillar BLG. These dyes demonstrated the same or higher emission intensity and selectivity to aggregated BLG as Thioflavin T, and are proposed for application in selective fluorescent detection of aggregated proteins.
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Affiliation(s)
- K D Volkova
- Institute of Molecular Biology and Genetics, National Academy of Sciences of Ukraine, 150 Zabolotnogo St., 03143 Kyiv, Ukraine
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26
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Segers-Nolten I, Veldhuis G, van der Werf K, van Raaij M, Subramaniam V. 2.305 The mechanism of alpha-synuclein fibril formation studied with high resolution Atomic Force Microscopy. Parkinsonism Relat Disord 2007. [DOI: 10.1016/s1353-8020(08)70704-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Veldhuis G, Agarwal A, Segers-Nolten I, Subramaniam V. 2.309 Induced folding of recombinant alpha-synuclein: Role of chemical chaperones. Parkinsonism Relat Disord 2007. [DOI: 10.1016/s1353-8020(08)70708-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Huisstede JHG, van der Werf KO, Bennink ML, Subramaniam V. Force constant calibration corrections for silicon position detectors in the near-infrared. Opt Express 2006; 14:8476-8481. [PMID: 19529225 DOI: 10.1364/oe.14.008476] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The accurate calibration of the force constant of the probe in atomic force microscopy and optical tweezers applications is extremely important for force spectroscopy. The commonly used silicon detectors exhibit a complex transfer function for wavelengths >850 nm, which limits the detection bandwidth leading to serious errors in the force constant determination. We show that this low-pass effect can be compensated for using the frequency response of the detector. This is applicable for calibrations in both atomic force microscopy and optical tweezers. For optical tweezers an additional correction method is discussed based on fitting an expression in which the low-pass characteristics are already accounted for.
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Hopman WCL, van der Werf KO, Hollink AJF, Bogaerts W, Subramaniam V, de Ridder RM. Nano-mechanical tuning and imaging of a photonic crystal micro-cavity resonance. Opt Express 2006; 14:8745-8752. [PMID: 19529256 DOI: 10.1364/oe.14.008745] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We show that nano-mechanical interaction using atomic force microscopy (AFM) can be used to map out mode-patterns of an optical micro-resonator with high spatial accuracy. Furthermore we demonstrate how the Q-factor and center wavelength of such resonances can be sensitively modified by both horizontal and vertical displacement of an AFM tip consisting of either Si(3)N(4) or Si material. With a silicon tip we are able to tune the resonance wavelength by 2.3 nm, and to set Q between values of 615 and zero, by expedient positioning of the AFM tip. We find full on/off switching for less than 100 nm vertical, and for 500 nm lateral displacement at the strongest resonance antinode locations.
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Walker TK, Subramaniam V, Stent HB, Butterworth J. A study of the mechanism of the degradation of citric acid by B. pyocyaneus (Pseudomonas pyocyanea): Action of B. pyocyaneus on succinic acid. Biochem J 2006; 25:129-37. [PMID: 16744558 PMCID: PMC1260619 DOI: 10.1042/bj0250129] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Affiliation(s)
- T K Walker
- The Chemistry Department, Municipal College of Technology, University of Manchester, and the Indian Institute of Science, Bangalore
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Huisstede JHG, van Rooijen BD, van der Werf KO, Bennink ML, Subramaniam V. Dependence of silicon position-detector bandwidth on wavelength, power, and bias. Opt Lett 2006; 31:610-2. [PMID: 16570414 DOI: 10.1364/ol.31.000610] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We have developed a two-LED wobbler system to generate the spatial displacement of total light intensity on a detector surface, facilitating the acquisition of frequency responses up to 600 kHz with high accuracy. We have used this setup to characterize the low-pass filtering behavior of silicon-based position detectors for wavelengths above 850 nm by acquiring the frequency responses of several quadrant detectors and position-sensitive detectors as functions of wavelength, applied bias voltage, and total light power. We observed an increase in bandwidth for an increase in applied bias voltage and incident-light intensity. The combined effect of these parameters is strongly dependent on the detector used and has significant implications for the use of these detectors in scanning probe and optical tweezers applications.
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Affiliation(s)
- J H G Huisstede
- Biophysical Engineering and MESA + Institute for Nanotechnology, Department of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
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Kassies R, van der Werf KO, Lenferink A, Hunter CN, Olsen JD, Subramaniam V, Otto C. Combined AFM and confocal fluorescence microscope for applications in bio-nanotechnology. J Microsc 2005; 217:109-16. [PMID: 15655068 DOI: 10.1111/j.0022-2720.2005.01428.x] [Citation(s) in RCA: 125] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We present a custom-designed atomic force fluorescence microscope (AFFM), which can perform simultaneous optical and topographic measurements with single molecule sensitivity throughout the whole visible to near-infrared spectral region. Integration of atomic force microscopy (AFM) and confocal fluorescence microscopy combines the high-resolution topographical imaging of AFM with the reliable (bio)-chemical identification capability of optical methods. The AFFM is equipped with a spectrograph enabling combined topographic and fluorescence spectral imaging, which significantly enhances discrimination of spectroscopically distinct objects. The modular design allows easy switching between different modes of operation such as tip-scanning, sample-scanning or mechanical manipulation, all of which are combined with synchronous optical detection. We demonstrate that coupling the AFM with the fluorescence microscope does not compromise its ability to image with a high spatial resolution. Examples of several modes of operation of the AFFM are shown using two-dimensional crystals and membranes containing light-harvesting complexes from the photosynthetic bacterium Rhodobacter sphaeroides.
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Affiliation(s)
- R Kassies
- BMTI Institute for Biomedical Technology, University of Twente, PO Box 217, 7500 AE Enschede, The Netherlands
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Huisstede J, van der Werf K, Bennink M, Subramaniam V. Force detection in optical tweezers using backscattered light. Opt Express 2005; 13:1113-1123. [PMID: 19494979 DOI: 10.1364/opex.13.001113] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
In force-measuring optical tweezers applications the position of a trapped bead in the direction perpendicular to the laser beam is usually accurately determined by measuring the deflection of the light transmitted through the bead. In this paper we demonstrate that this position and thus the force exerted on the bead can be determined using the backscattered light. Measuring the deflection for a 2.50 mum polystyrene bead with both a position sensitive detector (PSD) and a quadrant detector (QD) we found that the linear detection range for the PSD is approximately twice that for the QD. In a transmission-based setup no difference was found between both detector types. Using a PSD in both setups the linear detection range for 2.50 mum beads was found to be approximately 0.50 mum in both cases. Finally, for the reflection-based setup, parameters such as deflection sensitivity and linear detection range were considered as a function of bead diameter (in the range of 0.5-2.5 mum). 140pN was the largest force obtained using 2.50 mum beads.
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Subramaniam V, Li H, Wong M, Kitching R, Attisano L, Wrana J, Zubovits J, Burger AM, Seth A. The RING-H2 protein RNF11 is overexpressed in breast cancer and is a target of Smurf2 E3 ligase. Br J Cancer 2003; 89:1538-44. [PMID: 14562029 PMCID: PMC2394340 DOI: 10.1038/sj.bjc.6601301] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
The breast cancer-associated T2A10 clone was originally isolated from a cDNA library enriched for tumour messenger ribonucleic acids. Our survey of 125 microarrayed primary tumour tissues using affinity purified polyclonal antibodies has revealed that corresponding protein is overexpressed in invasive breast cancer and is weakly expressed in kidney and prostate tumours. Now known as RNF11, the gene encodes a RING-H2 domain and a PY motif, both of which mediate protein–protein interactions. In particular, the PPPPY sequence of RNF11 PY motif is identical to that of Smad7, which has been shown to bind to WW domains of Smurf2, an E3 ubiquitin ligase that mediates the ubiquitination and degradation of the TGFβ receptor complex. Using various mutants of RNF11 in GST pulldown and immunoprecipitation assays, we found that RNF11 interacts with Smurf2 through the PY motif, leading to ubiquitination of both proteins. Smurf2 plays an active role in the repression of TGFβ signalling, and our data indicate that overexpression of RNF11, through its interaction with Smurf2, can restore TGFβ responsiveness in transfected cells.
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Affiliation(s)
- V Subramaniam
- Laboratory of Molecular Pathology and Molecular and Cellular Biology Research, Sunnybrook and Women's College Health Sciences Centre, CIHR Group in Matrix Dynamics, University of Toronto, Toronto, Ontario, Canada
| | - H Li
- Laboratory of Molecular Pathology and Molecular and Cellular Biology Research, Sunnybrook and Women's College Health Sciences Centre, CIHR Group in Matrix Dynamics, University of Toronto, Toronto, Ontario, Canada
| | - M Wong
- Laboratory of Molecular Pathology and Molecular and Cellular Biology Research, Sunnybrook and Women's College Health Sciences Centre, CIHR Group in Matrix Dynamics, University of Toronto, Toronto, Ontario, Canada
| | - R Kitching
- Laboratory of Molecular Pathology and Molecular and Cellular Biology Research, Sunnybrook and Women's College Health Sciences Centre, CIHR Group in Matrix Dynamics, University of Toronto, Toronto, Ontario, Canada
| | - L Attisano
- Department of Biochemistry, Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada
| | - J Wrana
- Samuel Lunenfeld Research Institute, Mount Sinai Hospital, University of Toronto, Toronto, Ontario, Canada M5S 1A8
| | - J Zubovits
- Laboratory of Molecular Pathology and Molecular and Cellular Biology Research, Sunnybrook and Women's College Health Sciences Centre, CIHR Group in Matrix Dynamics, University of Toronto, Toronto, Ontario, Canada
| | - A M Burger
- Laboratory of Molecular Pathology and Molecular and Cellular Biology Research, Sunnybrook and Women's College Health Sciences Centre, CIHR Group in Matrix Dynamics, University of Toronto, Toronto, Ontario, Canada
| | - A Seth
- Laboratory of Molecular Pathology and Molecular and Cellular Biology Research, Sunnybrook and Women's College Health Sciences Centre, CIHR Group in Matrix Dynamics, University of Toronto, Toronto, Ontario, Canada
- Department of Laboratory Medicine and Pathobiology, University of Toronto, Toronto, Ontario, Canada. E-mail:
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Creemers T, Lock A, Subramaniam V, Jovin T, Völker S. Red-shifted mutants of green fluorescent protein: reversible photoconversions studied by hole-burning and high-resolution spectroscopy. Chem Phys 2002. [DOI: 10.1016/s0301-0104(01)00537-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Garcia-Parajo MF, Koopman M, van Dijk EM, Subramaniam V, van Hulst NF. The nature of fluorescence emission in the red fluorescent protein DsRed, revealed by single-molecule detection. Proc Natl Acad Sci U S A 2001; 98:14392-7. [PMID: 11724943 PMCID: PMC64692 DOI: 10.1073/pnas.251525598] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Recent studies on the newly cloned red fluorescence protein DsRed from the Discosoma genus have shown its tremendous advantages: bright red fluorescence and high resistance against photobleaching. However, it has also become clear that the protein forms closely packed tetramers, and there is indication for incomplete protein maturation with unknown proportion of immature green species. We have applied single-molecule methodology to elucidate the nature of the fluorescence emission in the DsRed. Real-time fluorescence trajectories have been acquired with polarization sensitive detection. Our results indicate that energy transfer between identical monomers occurs efficiently with red emission arising equally likely from any of the chromophoric units. Photodissociation of one of the chromophores weakly quenches the emission of adjacent ones. Dual color excitation (at 488 and 568 nm) single-molecule microscopy has been performed to reveal the number and distribution of red vs. green species within each tetramer. We find that 86% of the DsRed contain at least one green species with a red-to-green ratio of 1.2-1.5. On the basis of our findings, oligomer suppression would not only be advantageous for protein fusion but will also increase the fluorescence emission of individual monomers.
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Affiliation(s)
- M F Garcia-Parajo
- Applied Optics Group, Department of Applied Physics and MESA(+) Research Institute, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
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Abstract
Molecular beacons (MBs) are a novel class of nucleic acid probes that become fluorescent when bound to a complementary sequence. Because of this characteristic, coupled with the sequence specificity of nucleic acid hybridization and the sensitivity of fluorescence techniques, MBs are very useful probes for a variety of applications requiring the detection of DNA or RNA. We survey various applications of MBs, including the monitoring of DNA triplex formation, and describe recent developments in MB design that enhance their sensitivity.
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Affiliation(s)
- T Antony
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, D-37077 Goettingen, Germany
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Abstract
The Drosophila Bicoid (Bcd) protein plays a dual role as a transcription and translation factor dependent on the unique DNA and RNA binding properties of the homeodomain (HD). We have used circular dichroism and fluorescence spectroscopy to probe the structure and stability of the Bcd-HD, for which a high resolution structure is not yet available. The fluorescence from the single tryptophan residue in the HD (Trp-48) is strongly quenched in the native state but is dramatically enhanced ( approximately 20-fold) upon denaturation. Similar results were obtained with the Ultrabithorax HD (Ubx-HD), suggesting that the unusual tryptophan fluorescence may be a general phenomenon of HD proteins. We have used site-directed mutagenesis to explore the role of aromatic acids in the structure of the Bcd-HD and to evaluate the proposal that interactions between the strictly conserved Trp residue in HDs and nearby aromatic residues are responsible for the fluorescence quenching in the native state. We determined that both Trp-48 and Phe-8 in the N-terminal region of the HD are individually necessary for structural stability of the Bcd-HD, the latter most likely as a factor coordinating the orientation of the N-terminal helix I and the recognition helix for efficient binding to a DNA target.
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Affiliation(s)
- V Subramaniam
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, D-37077 Göttingen, Germany
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39
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Abstract
BACKGROUND Frequency-domain fluorescence lifetime imaging microscopy (FLIM) is finding increasing use in the analysis of biological systems. However, the calibration, determination of resolvable lifetime differences, and evaluation of artifacts have not been extensively treated. We describe a multi-point method for calibrating a frequency-domain FLIM system, characterize the minimum detectable heterogeneity and intra- and inter-image lifetime differences, discuss the statistical treatment of FLIM data, and suggest methods for minimizing artifacts. METHODS A set of solutions exhibiting single-component lifetimes suffice for accurately calibrating a reference material with a single-component lifetime, even in the absence of accurate data on the lifetimes of the individual solutions or the reference material. We used a set of rhodamine 6G solutions quenched with varying concentrations of iodide, leading to lifetimes of 0.5--4.0 ns, to calibrate a 1 microM reference solution of rhodamine 6G in water. RESULTS We measured a value of 4.11 ns with an estimated absolute error of +/-0.05 ns for the rhodamine 6G reference solution. With 57.7 MHz modulation, the minimum detectable inter-image lifetime difference was 0.1--0.15 ns and the minimum detectable intra-image lifetime difference was 4--5 ps, allowing solutions differing in lifetime by 40 and 70 ps to be easily distinguished. The minimum detectable lifetime heterogeneity was 50--80 ps. Evaluation of replicate measurements of single solutions demonstrated that inter-image instrument errors exceeded those predicted from intra-image statistics by more than an order of magnitude. We also measured lifetimes and heterogeneity in 4 GFP variants (WTGFP, EGFP, S65T, and EYFP) with the technique. CONCLUSION The multi-point calibration method is applicable to any system consisting of single-component lifetimes. Applying the method in our FLIM microscope allowed us to demonstrate a previously unreported degree of lifetime resolution in a FLIM microscope. Cytometry 43:248-260;2001.
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Affiliation(s)
- Q S Hanley
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany
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40
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Abstract
We have compared the binding of human full-length p53 protein (p53; expressed in bacteria and insects) and its isolated core domain (p53CD, amino acids 94-312; expressed in bacteria) to negatively supercoiled (sc) DNA using gel electrophoresis and immunoblotting. Significant differences were observed; p53CD produced a relatively small and continuous retardation of scDNA, in contrast to the ladder of distinct bands formed by p53 in agarose gels. The ladder produced by full-length protein expressed in bacteria (p53b) was similar to that observed earlier with protein expressed in insect cells (p53i). Competition between scDNAs and their linearized (lin) forms showed a preference for scDNAs by both p53 and p53CD, but the ratios characterizing the distribution of the protein between sc and lin pBluescript DNAs were substantially higher for p53 (sc/lin > 60 in p53b) than for p53CD (sc/lin approximately 4). Strong binding of p53 to scDNA lacking the p53 consensus sequence may represent a new p53-binding mode, which we tentatively denote supercoil-selective (SCS) binding. This binding requires both the C-terminal domain and the core domain. Targets of this binding may include: (a) DNA segments defined both by the nucleotide sequence and local topology, and/or (b) strand crossings and/or bending. The binding preference of p53CD for scDNA may be due to the known nonspecific binding to internal single-stranded regions in scDNA (absent in relaxed DNA molecules) and/or to SCS binding albeit with reduced affinity due to the absence of contributions from other p53 domains.
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Affiliation(s)
- E Palecek
- Institute of Biophysics, Academy of Sciences of the Czech Republic, 612 65 Brno, Czech Republic.
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41
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Jakobs S, Subramaniam V, Schönle A, Jovin TM, Hell SW. EFGP and DsRed expressing cultures of Escherichia coli imaged by confocal, two-photon and fluorescence lifetime microscopy. FEBS Lett 2000; 479:131-5. [PMID: 10981721 DOI: 10.1016/s0014-5793(00)01896-2] [Citation(s) in RCA: 118] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The green fluorescent protein (GFP) has become an invaluable marker for monitoring protein localization and gene expression in vivo. Recently a new red fluorescent protein (drFP583 or DsRed), isolated from tropical corals, has been described [Matz, M.V. et al. (1999) Nature Biotech. 17, 969-973]. With emission maxima at 509 and 583 nm respectively, EGFP and DsRed are suited for almost crossover free dual color labeling upon simultaneous excitation. We imaged mixed populations of Escherichia coli expressing either EGFP or DsRed by one-photon confocal and by two-photon microscopy. Both excitation modes proved to be suitable for imaging cells expressing either of the fluorescent proteins. DsRed had an extended maturation time and E. coli expressing this fluorescent protein were significantly smaller than those expressing EGFP. In aging bacterial cultures DsRed appeared to aggregate within the cells, accompanied by a strong reduction in its fluorescence lifetime as determined by fluorescence lifetime imaging microscopy.
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Affiliation(s)
- S Jakobs
- Max Planck Institute for Biophysicial Chemistry, High Resolution Optical Microscopy Group, Göttingen, Germany.
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42
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Abstract
We used scanning force microscopy to analyse the interaction of the core domain of the tumor suppressor protein p53 (p53CD, amino acid residues 94 to 312), with supercoiled DNA (scDNA) molecules. The complexes were attached to a mica substrate by the divalent cation spreading technique. p53CD bound to supercoiled plasmid pPGM1 bearing the consensus sequence 5'-AGACATGCCTAGACATGCCT-3' (p53CON) was imaged as a globular complex. Only one such complex was observed with each scDNA molecule. In contrast, binding to supercoiled pBluescript II SK(-) DNA (lacking the consensus sequence) resulted in the appearance of multiple, variable size complexes of various sizes on single DNA molecules. Addition of p53CD to scDNA containing a cruciform-forming (AT)(34) insert resulted in the binding of the protein exclusively at the cruciform. The data presented here suggest that p53CD can form stable specific and non-specific complexes with supercoiled DNA molecules, albeit of variable multimeric organization.
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Affiliation(s)
- S D Jett
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, Göttingen, D-37077, Germany
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43
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Creemers TM, Lock AJ, Subramaniam V, Jovin TM, Völker S. Photophysics and optical switching in green fluorescent protein mutants. Proc Natl Acad Sci U S A 2000; 97:2974-8. [PMID: 10716703 PMCID: PMC16176 DOI: 10.1073/pnas.97.7.2974] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
We demonstrate by using low-temperature high-resolution spectroscopy that red-shifted mutants of green fluorescent protein are photo-interconverted among three conformations and are, therefore, not photostable "one-color" systems as previously believed. From our experiments we have further derived the energy-level schemes governing the interconversion among the three forms. These results have significant implications for the molecular and cell biological applications of the green fluorescent protein family; for example, in fluorescence resonant energy transfer experiments, a change in "color" on irradiation may not necessarily be due to energy transfer but can also arise from a photo-induced conversion between conformers of the excited species.
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Affiliation(s)
- T M Creemers
- Center for the Study of Excited States of Molecules, Huygens and Gorlaeus Laboratories, University of Leiden, P.O. Box 9504, 2300 RA Leiden, The Netherlands
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44
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Abstract
We have used one- (OPE) and two-photon (TPE) excitation with time-correlated single-photon counting techniques to determine time-resolved fluorescence intensity and anisotropy decays of the wild-type Green Fluorescent Protein (GFP) and two red-shifted mutants, S65T-GFP and RSGFP. WT-GFP and S65T-GFP exhibited a predominant approximately 3 ns monoexponential fluorescence decay, whereas for RSGFP the main lifetimes were approximately 1.1 ns (main component) and approximately 3.3 ns. The anisotropy decay of WT-GFP and S65T-GFP was also monoexponential (global rotational correlation time of 16 +/- 1 ns). The approximately 1.1 ns lifetime of RSGFP was associated with a faster rotational depolarization, evaluated as an additional approximately 13 ns component. This feature we attribute tentatively to a greater rotational freedom of the anionic chromophore. With OPE, the initial anisotropy was close to the theoretical limit of 0.4; with TPE it was higher, approaching the TPE theoretical limit of 0.57 for the colinear case. The measured power dependence of the fluorescence signals provided direct evidence for TPE. The general independence of fluorescence decay times, rotation correlation times, and steady-state emission spectra on the excitation mode indicates that the fluorescence originated from the same distinct excited singlet states (A*, I*, B*). However, we observed a relative enhancement of blue fluorescence peaked at approximately 440 nm for TPE compared to OPE, indicating different relative excitation efficiencies. We infer that the two lifetimes of RSGFP represent the deactivation of two substates of the deprotonated intermediate (I*), distinguished by their origin (i.e., from A* or B*) and by nonradiative decay rates reflecting different internal environments of the excited-state chromophore.
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Affiliation(s)
- A Volkmer
- Photophysics Research Group, Department of Physics and Applied Physics, University of Strathclyde, 107 Rottenrow, Glasgow G4 ONG, Scotland, United Kingdom
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Fojta M, Brazdova M, Cernocka H, Pecinka P, Brazda V, Palecek J, Jagelska E, Vojtesek B, Pospisilova S, Subramaniam V, Jovin TM, Palecek E. Effects of Oxidation Agents and Metal Ions on Binding of p53 to Supercoiled DNA. J Biomol Struct Dyn 2000; 17 Suppl 1:177-83. [DOI: 10.1080/07391102.2000.10506618] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Cherny DI, Striker G, Subramaniam V, Jett SD, Palecek E, Jovin TM. DNA bending due to specific p53 and p53 core domain-DNA interactions visualized by electron microscopy. J Mol Biol 1999; 294:1015-26. [PMID: 10588903 DOI: 10.1006/jmbi.1999.3299] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have used transmission electron microscopy to analyze the specificity and the extent of DNA bending upon binding of full-length wild-type human tumor suppressor protein p53 (p53) and the p53 core domain (p53CD) encoding amino acid residues 94-312, to linear double-stranded DNA bearing the consensus sequence 5'-AGACATGCCTAGACATGCCT-3' (p53CON). Both proteins interacted with high specificity and efficiency with the recognition sequence in the presence of 50 mM KCl at low temperature ( approximately 4 degrees C) while the p53CD also exhibits a strong and specific interaction at physiological temperature. Specific complex formation did not result in an apparent reduction of the DNA contour length. The interaction of p53 and the p53CD with p53CON induced a noticeable salt-dependent bending of the DNA axis. According to quantitative analysis with folded Gaussian distributions, the bending induced by p53 varied from approximately 40 degrees to 48 degrees upon decreasing of the KCl concentration from 50 mM to approximately 1 mM in the mounting buffer used for adsorption of the complexes to the carbon film surface. The p53CD bent DNA by 35-37 degrees for all salt concentrations used in the mounting buffer. The bending angle of the p53/DNA complex under low salt conditions showed a somewhat broader distribution (sigma approximately 39 degrees ) than at high salt concentration (sigma approximately 31 degrees ) or for p53CD (sigma approximately 24-27 degrees ). Together, these results demonstrate that the p53CD has a dominant role in complex formation and that the complexes formed both by p53 and p53CD under moderate salt conditions are similar. However, the dependence of the bending parameters on ambient conditions suggest that the segments flanking the p53CD contribute to complex formation as well. The problems associated with the analysis of bending angles in electron microscopy experiments are discussed.
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Affiliation(s)
- D I Cherny
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, Göttingen, D-37077, Germany.
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Creemers TM, Lock AJ, Subramaniam V, Jovin TM, Völker S. Three photoconvertible forms of green fluorescent protein identified by spectral hole-burning. Nat Struct Biol 1999; 6:557-60. [PMID: 10360360 DOI: 10.1038/9335] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Several studies have led to the conclusion that, in the green fluorescent protein (GFP) of the jellyfish Aequorea victoria, a photoconversion involving excited-state proton transfer occurs from an A- to a B-form, while an intermediate I-form was held responsible for the green fluorescence. Here we have identified the I-form of wild-type GFP in absorption, located the 0-0 transitions of all three forms A, B and I, and determined vibrational frequencies of the ground and excited states. The intrinsically narrow 0-0 transitions are revealed by the wavelengths at which holes can be burnt. The pathways of photointerconversion are unraveled by excitation, emission and hole-burning spectroscopy. We present an energy-level scheme that has significant implications for GFP-mutants, which likewise can occur in the three photo-interconvertible forms.
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Affiliation(s)
- T M Creemers
- Center for the Study of the Excited States of Molecules, Huygens and Gorlaeus Laboratories, University of Leiden, The Netherlands
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48
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Abstract
To study the process of establishment, and evaluate the outcome of participation, in a self-help support group for people with chronic nonmalignant pain, members of a newly-established, consumer-led group participated in two interviews 5 months apart and a researcher observed group meetings. Participants reported significant benefits from participating in the group. They had a significant increase in functional ability and activity, and reported decreased recourse to health professionals, particularly family physicians. This study indicates that pain support groups can play a valuable role for people in pain, assisting with support and rehabilitation, and meeting needs that health professionals are often not appropriate or able to provide.
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Affiliation(s)
- V Subramaniam
- Asian Pacific Resource and Research Center for Women, Kuala Lumpur, Malaysia
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49
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Abstract
Fluorescence resonance energy transfer (FRET) between excited fluorescent donor and acceptor molecules occurs via the Förster mechanism over a range of 1-10 nm. Because of the strong (sixth power) distance dependence of the signal, FRET has been used to assess the proximity of molecules in biological systems. We used a scanning near-field optical microscope (SNOM) operated in the shared-aperture mode using uncoated glass fibre tips to detect FRET between dye molecules embedded in polyvinyl alcohol films and bound to cell surfaces. FRET was detected by selective photobleaching of donor and acceptor fluorophores. We also present preliminary results on pixel-by-pixel energy transfer efficiency measurements using SNOM.
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Affiliation(s)
- A K Kirsch
- Department of Molecular Biology, Max Planck Institute of Biophysical Chemistry, Göttingen, Germany
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50
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Abstract
We have implemented simultaneous picosecond pulsed two- and three-photon excitation of near-UV and visible absorbing fluorophores in a scanning near-field optical microscope (SNOM). The 1064-nm emission from a pulsed Nd:YVO4 laser was used to excite the visible mitochondrial specific dye MitoTracker Orange CM-H2TMRos or a Cy3-labeled antibody by two-photon excitation, and the UV absorbing DNA dyes DAPI and the bisbenzimidazole BBI-342 by three-photon excitation, in a shared aperture SNOM using uncoated fiber tips. Both organelles in human breast adenocarcinoma cells (MCF 7) and specific protein bands on polytene chromosomes of Drosophila melanogaster doubly labeled with a UV and visible dye were readily imaged without photodamage to the specimens. The fluorescence intensities showed the expected nonlinear dependence on the excitation power over the range of 5-40 mW. An analysis of the dependence of fluorescence intensity on the tip-sample displacement normal to the sample surface revealed a higher-order function for the two-photon excitation compared to the one-photon mode. In addition, the sample photobleaching patterns corresponding to one- and two-photon modes revealed a greater lateral confinement of the excitation in the two-photon case. Thus, as in optical microscopy, two-photon excitation in SNOM is confined to a smaller volume.
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Affiliation(s)
- A Jenei
- Department of Molecular Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, D-37077 Gottingen, Germany
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