Alfvén pulse driven spicule-like jets in the presence of thermal conduction and ion-neutral collision in two-fluid regime

We present the formation of quasi-periodic cool spicule-like jets in the solar atmosphere using 2.5-D numerical simulation in two-fluid regime (ions+neutrals) under the presence of thermal conduction and ion-neutral collision. The nonlinear, impulsive Alfvénic perturbations at the top of the photosphere trigger field aligned magnetoacoustic perturbations due to ponderomotive force. The transport of energy from Alfvén pulse to such vertical velocity perturbations due to ponderomotive force is considered as an initial trigger mechanism. Thereafter, these velocity perturbations steepen into the shocks followed by quasi-periodic rise and fall of the cool jets transporting mass in the overlying corona. This article is part of the theme issue 'Partially ionized plasma of the solar atmosphere: recent advances and future pathways'.

Endoscopic MIS-TLIF with Destandau's system: leveraging endoscopy with conventional instruments

This presentation showcases an endoscopic minimally invasive spine surgery (MISS) technique for lumbar interbody fusion. Significantly expanding the scope of Destandau's system within MISS, it serves as a pivotal link to unilateral biportal endoscopy (UBE) for endofusion. The method involves minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) using a 4-mm rigid endoscope through Destandau's system. With the widespread familiarity with Destandau's system and the absence of specialized instrument requirements, this approach is easily adoptable, particularly in resource-limited centers. The favorable clinical and radiological outcomes underscore the effectiveness of this technique, propelling the role of endoscopy in MISS, particularly in endofusion. The video can be found here: https://stream.cadmore.media/r10.3171/2024.1.FOCVID23216.

Proteomic-miRNA Biomics Profile Reveals 2D Cultures of Human iPSC-Derived Neural Progenitor Cells More Sensitive than 3D Spheroid System Against the Experimental Exposure to Arsenic

The iPSC-derived 3D models are considered to be a connective link between 2D culture and in vivo studies. However, the sensitivity of such 3D models is yet to be established. We assessed the sensitivity of the hiPSC-derived 3D spheroids against 2D cultures of neural progenitor cells. The sub-toxic dose of Sodium Arsenite (SA) was used to investigate the alterations in miRNA-proteins in both systems. Though SA exposure induced significant alterations in the proteins in both 2D and 3D systems, these proteins were uncommon except for 20 proteins. The number and magnitude of altered proteins were higher in the 2D system compared to 3D. The association of dysregulated miRNAs with the target proteins showed their involvement primarily in mitochondrial bioenergetics, oxidative and ER stress, transcription and translation mechanism, cytostructure, etc., in both culture systems. Further, the impact of dysregulated miRNAs and associated proteins on these functions and ultrastructural changes was compared in both culture systems. The ultrastructural studies revealed a similar pattern of mitochondrial damage, while the cellular bioenergetics studies confirm a significantly higher energy failure in the 2D system than to 3D. Such a higher magnitude of changes could be correlated with a higher amount of internalization of SA in 2D cultures than in 3D spheroids. Our findings demonstrate that a 2D culture system seems better responsive than a 3D spheroid system against SA exposure.

An institutional study on accuracy of freehand cervical C1 C2 screws placement by knock and drill technique in craniovertebral anomalous bony anatomy: An evaluation of more than 600 screws based on SGPGI screw accuracy criteria

Purpose

To assess the accuracy of freehand cervical C1 C2 screws placement by knock and drill (K and D) technique in craniovertebral anomalous bony anatomy.

Materials and Methods

From January 2017 to December 2022, 682 consecutive C1 C2 screws in 215 patients with craniovertebral junction (CVJ) anomalies were enrolled. All patients underwent posterior fixation with K and D technique without any fluoroscopic guidance. The patient's demographic details, clinical details, radiological details, major intraoperative events, and postoperative complications were noted. The screws malposition grades and direction on CT images in the axial and sagittal plane were defined as new per proposed "SGPGI accuracy criteria." All patients had a clinical evaluation at 3-month follow-up.

Results

Total 682 C1, C2 screws were placed in 215 patients for CVJ anomalies using K and D technique. The accuracy of screws placement by freehand technique was 84.46% (576/682). So with technique explained the rate of malplacement in simple (16.35%) and complex (15.19%) groups were almost comparable and comparison difference was not significant (P = 0.7005).

Conclusion

The freehand technique, as described, is effective in cases of anomalous bony anatomy, and it is mandatory in complex CVJ anomalies. The accuracy of screw placement and VA injury is comparable with major studies. This technique is supposedly cost-effective and less hazardous to both health-care workers and patients.

Stereotactic biopsy for brain lesions: Doing more with less

Objectives

Stereotactic biopsy (STB) is a potential diagnostic tool considering its minimal invasiveness, high diagnostic yield, and minimal associated complications. Over the years, various frame-based instrument systems and frameless stereotactic biopsy systems have emerged to be employed in clinical use. With this study, we intend to get more by doing less in the form of STB for the patients of doubtful intracranial lesions treated over the past 5 years. We also want to highlight the technique of performing the procedure under scalp block, which can be used as a versatile tool in many clinical scenarios. Stereotactic biopsies may be planned even in rural district-level health facilities. One-time investment to procure instruments and avail existing imaging can lead to establishing definitive diagnoses in many doubtful cases. This will result in lesser cost and early establishment of treatment. Independent risk factors determining the outcome, such as deep-seated lesions, associated edema, and intraoperative hypertension, were studied. Establishing the diagnosis helped in prognosticating the disease, explaining the natural progression of symptoms, and starting adjuvant therapy. This tissue biopsy would also help secure samples for research and molecular analysis.

Materials and Methods

Twenty patients underwent STBs at our institution between January 2018 and December 2022. We retrospectively analyzed patient characteristics, tumor pathology, surgical procedures, and outcomes, including the diagnostic value and surgery-related complications. These patients were followed up, and their progression-free and overall survival were analyzed. The need for adjuvant treatment was noted and analyzed. All procedures were performed using Cosman Roberts Wells® stereotactic frame. Pre-procedure magnetic resonance scans were performed at the time of admission. Contrast-enhanced computerized tomography (CT) scan after frame application was performed to identify targets and calculate the coordinates. A post-procedure CT scan was done to confirm the accessibility of the targeted lesion.

Results

The most common location of the tumor was a deep-seated thalamic lesion. A definitive diagnosis was established in 19 patients (95%) at the first STB. The diagnoses were glioma in 55% of cases, primary central nervous system lymphoma, tuberculosis, and demyelinating disorders in 10% of each, and a metastatic brain tumor in 1 (5%). The post-operative complications were all transient except in one patient with deterioration of motor weakness. The follow-up was noted, and modes of adjuvant treatment needed in these patients were recorded.

Conclusion

Stereotactic biopsy is a useful and effective method for achieving a definitive diagnosis and aiding in treating multifocal or small deep-seated lesions in or around eloquent regions.

Factors predicting seizure outcome after surgical excision of meningioma: SOLID-C guideline for prophylactic AED

BACKGROUND

Seizures are commonly seen among meningioma patients and may cause impaired quality of life. These patients can be effectively treated with surgery. Still, many patients have persistent seizure episodes after surgery. The factors which are associated with worsening of seizure episodes remain critical in improving the quality of life for such patients. In this study, we aim to analyze the clinical and histopathological factors to predict the post excision seizure-outcome in meningioma and need of antiepileptic prophylaxis for these patients.

METHODS

Adult patients who underwent primary resection of meningioma at our institute between 2007 and 2020 were included in the study. Eligibility criteria were as follows: (i) Surgery for newly-diagnosed biopsy proven meningioma, (ii) Presence of pre-operative seizure (iii) A follow-up period ≥ 12 months.

RESULTS

Of the 1145 patients in this series, 333 patients were recruited in study. The major determinants of prophylactic anti-epileptic were tumour size (S), Oedema (O), location (L), inclusion body (I), antiepileptic drugs (D) and surgical complication (C). The factors independently associated with poor seizure control after surgical resection were presence of brain parenchyma invasion (p < 0.001), pre-operative use of > 2 antiepileptics (p = 0.016) and presence of intranuclear inclusion bodies (p = 0.001).

CONCLUSIONS

The identification and consideration of factors associated with prolonged seizure control after surgery may help us to guide treatment strategies aimed at improving the quality of life for patients with meningiomas. Authors have proposed a SOLID-C guideline to avoid the blanket approach of prophylactic AED in patients undergoing for meningioma resection.

Prophylactic Para-Aortic Extended Field Irradiation with Concurrent Chemotherapy for FIGO Stage IIIC1 Cervical Cancer Using Intensity Modulated Radiotherapy Technique: Acute Toxicity and Dosimetric Assessment

PURPOSE/OBJECTIVE(S)

To evaluate the efficacy of P - PART with concurrent chemotherapy in LACC with the use of intensity modulated radiotherapy technique (IMRT). Our Primary endpoint was to assess acute toxicities and secondary endpoint was to assess loco-regional control (LRC), disease free-survival (DFS), para-aortic recurrence free survival (PA-RFS).

MATERIALS/METHODS

A total of 30 patients of squamous cell carcinoma of cervix with stage IIIC1 (FIGO-2018) were recruited in this prospective, single arm interventional phase II study between January 2021 to September 2022. 18FDG-PET CT was performed and those with positive PALN were excluded. IMRT was used to deliver a dose of 50 Gy in 25 fractions to whole pelvis and PALN chain below renal hilum till aortic bifurcation received 45 Gy in 25 fractions. Concurrent cisplatin was administered weekly at 40 mg/m2 during radiation. On completion of external beam radiotherapy, high dose rate intracavitary brachytherapy was given at 7 Gy per fraction in 3 fractions prescribed to HR-CTV. Acute toxicities were assessed using CTCAE version 5.0.

RESULTS

Median age was 50 years (37-66 years). All patients had completed treatment as per protocol. All patients had positive pelvic nodes with the maximum nodal short axis dimension of 14 mm (10-18 mm). All patients had positive internal iliac group of LNs, only 2(6.6%) patients had positive common iliac group of Ln. Median number of concurrent cisplatin cycles given were 5 (3-5 cycle). Median overall treatment time was 56 days (52-63 days) and median follow up was 15 months (3-22 month). Median cumulative dose to HR-CTV was 84.3Gy (Range:79.2-86.9Gy). Cumulative median EQD2 to 2cc of bladder and rectum were 69.11Gy (Range:59.17 - 80.07 Gy) and 64.6 Gy (Range: 60.1-66.3Gy) respectively. 7(23.3%) patients having grade 3 diarrhea and 2(6.67%) patients had grade 3 anemia while no significant genitourinary or other toxicities were noted. Patient characteristics, dosimetric data are described in Table-1. All patients underwent clinical and radiological assessment at the time of last follow up with one (3.33%) patient experiencing local failure at 9 months of follow up, hence crude LRC rate is 96.6%, DFS is 13.5 months (5-22 months) and PA-RFS is 16 months (8-23 months) till last date of follow up.

CONCLUSION

Prophylactic EFRT with concurrent chemotherapy using IMRT technique yielded excellent short term clinical outcomes with acceptable toxicity profiles. Longer follow up will elucidate late toxicity and long-term clinical outcomes.

Clinicoradiologic Risk Stratification and Outcome Assessment in Symptomatic Intracranial Arachnoid Cyst Managed Over Fifteen Years

BACKGROUND

Arachnoid cysts (ACs) are developmental anomalies formed by splitting the arachnoid membrane's layers. ACs contribute around 2% of all intracranial space-occupying lesions. ACs are more prevalent in children. Because of varied clinical presentation, there has been a constant need for clinicoradiologic risk stratification with a possible role in outcome prediction. The present study describes the management strategies and outcomes in symptomatic intracranial ACs.

METHODS

All biopsy-proven symptomatic patients who underwent surgical management over last 15 years were included in this study (January 2008-December 2022), while those with non-conclusive biopsies were excluded. Patients presenting with acute deterioration were managed in the emergency department with or without cerebrospinal fluid diversion and decompression of the AC. The microsurgical or endoscopic approach was the preferred surgical modality. Postoperative clinicoradiologic improvement was evaluated at 3 months follow-up visit.

RESULTS

A total of 108 patients were analyzed in this retrospective observational study. The median age of the patients was 27.5 years (range, 1 to 76 years). Headache was the most typical clinical presentation. Supratentorial ACs (n = 59, 54.6%) were higher than the infratentorial ACs (n = 49, 45.4%). Forty-seven patients belonged to the pediatric age group (<18 years), and seizure was their presenting complaint. In this observational study, there was no statistical difference in operative duration between microsurgical technique versus endoscopic decompression (P= 0.23).

CONCLUSIONS

ACs are uncommon brain lesions having a broad spectrum of symptoms. The location and clinical presentation of ACs decide the preferred surgical approach. Individuals in high-risk groups must be treated on priority to achieve long-term relief of symptoms.

Prospective Evaluation of Locoregional Control in Oral Cavity Squamous Cell Carcinoma with Infratemporal Fossa Involvement Treated with Surgery and Adjuvant Concurrent Chemoradiotherapy

PURPOSE/OBJECTIVE(S)

Oral cavity squamous cell carcinoma (OCSCC) is the most common head and neck cancer in India. Definitive surgery with or without post-op radiotherapy (PORT) with or without chemotherapy (CT) provides better outcomes in locally advanced OCSCC as compared to definitive chemoradiotherapy. T4b OCSCC with infra temporal fossa (ITF) involvement has varied outcome depending on the extent of ITF involvement, with low and mid ITF having relatively favorable prognosis. We aimed to prospectively evaluate outcomes in patients of OCSCC with low or mid ITF involvement treated with curative surgery followed by adjuvant concurrent chemoradiotherapy (CCRT).

MATERIALS/METHODS

A total of 20 patients of T4b OCSCC (as per AJCC 8th edition) with low or mid ITF involvement were included in this single arm prospective interventional study from January 2021 to October 2022. Patients with involvement of skull base, carotid artery, prevertebral fascia and/or pterygomaxillary fissure were excluded. All patients were treated with definitive surgery with ITF clearance followed by adjuvant CCRT as indicated. Loco-regional control (LRC), Disease free survival (DFS), Overall survival (OS) were assessed using Kaplan-Meier survival analysis. Acute toxicities were assessed according to the CTCAE v5.0.

RESULTS

Patient characteristics are summarized in table 1. Median follow-up was 11.5 months (4-21months). All patients received adjuvant CCRT with weekly cisplatin 40mg/m2 to a median number of 6 cycles (5-7 cycles). Median RT dose was 64Gy (60-64Gy). All patients tolerated treatment well. Grade 3 oral mucositis, odynophagia were seen in 8 (40%) patients each and skin toxicity, oral pain in 6 (30%) and 5 (25%) patients respectively. No grade 4 toxicities were observed LRC at three month was 73.68% with 4 local and 1 locoregional failure only. LRC at one year was 36.8% with 8 local, 1 locoregional, 2 locodistant and 1 distant failure only. Median DFS was 10.4 months. Median OS was not reached; four patients died. LRC at three months was better for patients with low ITF disease as compared to mid ITF disease (85.7% vs. 40% (p = 0.04) and at one year was 42.8% vs. 40% (p = 0.50).

CONCLUSION

Selected patient of locally advanced OCSCC with low ITF involvement may benefit from trimodality therapy of surgery with ITF clearance followed by adjuvant CCRT. Acute toxicity profile was acceptable in our study.

Proteome architecture of human-induced pluripotent stem cell-derived three-dimensional organoids as a tool for early diagnosis of neuronal disorders

BACKGROUND AND OBJECTIVES

Induced pluripotent stem cells (iPSCs) derived three-dimensional (3D) model for rare neurodegenerative disorders such as amyotrophic lateral sclerosis (ALS) is emerging as a novel alternative to human diseased tissue to explore the disease etiology and potential drug discovery. In the interest of the same, we have generated a TDP-43-mutated human iPSCs (hiPSCs) derived 3D organoid model of ALS disease. The high-resolution mass spectrometry (MS)-based proteomic approach is used to explore the differential mechanism under disease conditions and the suitability of a 3D model to study the disease.

MATERIALS AND METHODS

The hiPSCs cell line was procured from a commercial source, grown, and characterized following standard protocols. The mutation in hiPSCs was accomplished using CRISPR/Cas-9 technology and predesigned gRNA. The two groups of organoids were produced by normal and mutated hiPSCs and subjected to the whole proteomic profiling by high-resolution MS in two biological replicates with three technical replicas of each.

RESULTS

The proteomic analysis of normal and mutated organoids revealed the proteins associated with pathways of neurodegenerative disorders, proteasomes, autophagy, and hypoxia-inducible factor-1 signaling. Differential proteomic analysis revealed that the mutation in TDP-43 gene caused proteomic deregulation, which impaired protein quality mechanisms. Furthermore, this impairment may contribute to the generation of stress conditions that may ultimately lead to the development of ALS pathology.

CONCLUSION

The developed 3D model represents the majority of candidate proteins and associated biological mechanisms altered in ALS disease. The study also offers novel protein targets that may uncloud the precise disease pathological mechanism and be considered for future diagnostic and therapeutic purposes for various neurodegenerative disorders.

Insular glioblastoma: surgical challenges, survival outcomes and prognostic factors

BACKGROUND

Insular gliomas are unique, challenging and evoke a lot of interest amongst neurosurgeons. Publications on insular glioma generally focus on the surgical intricacies and extent of resection pertaining to the low-grade gliomas. Insular glioblastomas (iGBM) have not been analysed separately before.

METHODS

Histologically proven WHO grade IV gliomas involving the insula over a 9-year period were studied. Their clinical presentation, radiological features, surgical findings and survival outcomes were assessed. Statistical methods were used to determine the favourable predictors of survival.

RESULTS

Out of 27 patients (M:F = 2.9:1), 18 (66%) patients had a tumour extension beyond the insula, 10 (37%) of whom had basal ganglia involvement. Total, near total and subtotal excisions were performed in 7 (26%), 9 (33%) and 11 (40.7%) patients, respectively. Twenty-three patients had glioblastoma, while four had gliosarcoma. IDH mutation was negative in six of the seven patients where it was done. Median overall survival was 5 months. Multivariate analysis showed that a female gender (p = 0.013), seizures in the preoperative period (p = 0.048) and completion of adjuvant therapy (p = 0.003) were associated with a longer survival.

CONCLUSION

Insular glioblastomas have a poor prognosis. Insular location and certain tumour characteristics often limit the extent of resection of iGBMs. Moreover, postoperative complications sometimes negate the advantages of a radical resection. A female gender, presentation with seizures and completion of adjuvant chemoradiotherapy appear to be good prognostic factors.

Preparation of nanolignin rich fraction from bamboo stem via green technology: assessment of its antioxidant, antibacterial and UV blocking properties

This work reports the preparation of nano lignin-rich fraction material via green technology from the holistic use of lignocellulosic biomass bamboo. The bamboo is first chemically treated, followed by acid precipitation to extract bamboo-derived macro lignin-rich fraction material. The nano lignin-rich fraction material was then prepared via ultrasonication technique from the extracted bamboo-derived macro lignin-rich fraction material. The confirmation of the distinct lignin functional groups in the extracted lignin-rich fractions has been done by FTIR. Surface morphology by FESEM and TEM revealed spherical nano-lignin-rich fraction materials from extracted bamboo-derived macro lignin-rich fraction materials. DPPH assays indicated that both the obtained fractions depict beneficial antioxidant characteristics. They were found to be effective in terms of their antibacterial activity against both gram-positive bacteria Staphylococcus aureus (S.aureus) and gram-negative bacteria Escherichia coli (E.coli), using the disc diffusion method. These fractions have UV blocking property, and nano-lignin-rich fraction material acts as a more potential UV blocking agent than others. Thus, the nano-lignin-rich fraction material has great potential as a high antioxidant, antibacterial, and UV blocking agent useful in biomedical applications.Highlights Extraction of macro-lignin rich fraction material using chemical treatment of lignocellulosic biomass bamboo via refluxing followed by acid precipitation.Preparation of nano-lignin rich fraction material from extracted bamboo-derived macro-lignin rich fraction material via ultrasonication technique as a green technology.Structural and surface morphology of the extracted macro-lignin & nano lignin-rich fraction materials have been analyzed by XRD, FTIR, EDX, SEM and TEM.The macro lignin & nano lignin-rich fraction materials showed good antioxidant, antibacterial activity and UV-blocking properties, but the nano-lignin rich fraction material exhibited more efficient properties.

Quantitative assessment of brainstem distortion in vestibular schwannoma and its implication in occurrence of hydrocephalus

PURPOSE

Anatomical distortion directly affects the clinical status of patients with vestibular schwannomas (VSs). It may vary for a given tumor size due to variability in posterior fossa anatomy. We aimed to quantitatively assess brainstem distortion (BSD) and review its role in occurrence of hydrocephalus associated with VSs.

METHODS

Sixty-six patients with small (<3 cm, n= 8; 12.1%); large (3-4 cm; n= 26; 39.4%) and giant (>4 cm; n= 32; 48.5%) VSs were included. Cystic VSs were excluded. Tumor size, tumor-extent, linear displacement (LD; distance between line bisecting pons (line 1) and posterior fossa midline (line 2)) and angular distortion (AD; angle subtended between lines 1 and 2) in axial-T2-MRI section through pons, and their effect on hydrocephalus were assessed.

RESULTS

Significant BSD occurred in a younger age (p value = .004/.003), larger-sized tumor (p value = .001/.002), hydrocephalus (p value = .001/.001), trigeminal (V) nerve palsy (p value = .004/.003) and long tract signs (p value = .001/.034). Tumors crossing midline had significant association with hydrocephalus (p value = .003). LD increased progressively even for 4-5 cm-sized tumors while AD stabilized. Receiver operating characteristic (ROC) curve revealed that diagnostic accuracy of LD (area under the ROC curve (AUROC): 78.9% (95% CI: 67.2%, 90.5%, p < .001)), AD (AUROC:77.6% (95% CI:65.8%, 89.5%, p < .001)) and LD × AD (AUROC:80.3% (95% CI: 69.2%, 91.2%, p < .001)) for predicting occurrence of hydrocephalus was better than tumor size (AUROC: 66.7% (95% CI: 53.5%, 79.9%, p < .05). Cut-off values of LD and AD for predicting occurrence of hydrocephalus were 6.25 mm and 14.6°, respectively. Hydrocephalus was significantly more when both LD was greater than  6.25 mm and AD was greater than 14.5° (p value = .034). The role of LD and AD in influencing hydrocephalus was greater than categorization based on tumor size (Spearman's correlation coefficient: 0.535 and 0.248, respectively). Hydrocephalus occurred at a lesser cut-off value of LD and AD when compared to long tract signs.

CONCLUSIONS

LD and AD values in VSs have a significantly greater influence in the development of hydrocephalus compared to tumor size, and may aid, more reliably, in the prediction of hydrocephalus.

Climatology and model prediction of aerosol optical properties over the Indo-Gangetic Basin in north India

The current research focuses on the use of different simulation techniques in the future prediction of the crucial aerosol optical properties over the highly polluted Indo-Gangetic Basin in the northern part of India. The time series model was used to make an accurate forecast of aerosol optical depth (AOD) and angstrom exponent (AE), and the statistical variability of both cases was compared in order to evaluate the effectiveness of the model (training and validation). For this, different models were used to simulate the monthly average AOD and AE over Jaipur, Kanpur and Ballia during the period from 2003 to 2018. Further, the study was aimed to construct a comparative model that will be used for time series statistical analysis of MODIS-derived AOD₅₅₀ and AE_412-470. This will provide a more comprehensive information about the levels of AOD and AE that will exist in the future. To test the validity and applicability of the developed models, root-mean-square error (RMSE), mean absolute error (MAE), mean absolute percent error (MAPE), fractional bias (FB), and Pearson coefficient (r) were used to show adequate accuracy in model performance. From the observation, the monthly mean values of AOD and AE were found to be nearly similar at Kanpur and Ballia (0.62 and 1.26) and different at Jaipur (0.25 and 1.14). Jaipur indicates that during the pre-monsoon season, the AOD mean value was found to be highest (0.32 ± 0.15), while Kanpur and Ballia display higher AOD mean values during the winter season (0.72 ± 0.26 and 0.83 ± 0.32, respectively). Among the different methods, the autoregressive integrated moving average (ARIMA) model was found to be the best-suited model for AOD prediction at Ballia based on fitted error (RMSE (0.22), MAE (0.15), MAPE (24.55), FB (0.05)) and Pearson coefficient r (0.83). However, for AE, best prediction was found at Kanpur based on RMSE (0.24), MAE (0.21), MAPE (22.54), FB (-0.09) and Pearson coefficient r (0.82).

Search for Subsolar-Mass Binaries in the First Half of Advanced LIGO's and Advanced Virgo's Third Observing Run

We report on a search for compact binary coalescences where at least one binary component has a mass between 0.2  M_{⊙} and 1.0  M_{⊙} in Advanced LIGO and Advanced Virgo data collected between 1 April 2019 1500 UTC and 1 October 2019 1500 UTC. We extend our previous analyses in two main ways: we include data from the Virgo detector and we allow for more unequal mass systems, with mass ratio q≥0.1. We do not report any gravitational-wave candidates. The most significant trigger has a false alarm rate of 0.14  yr^{-1}. This implies an upper limit on the merger rate of subsolar binaries in the range [220-24200]  Gpc^{-3} yr^{-1}, depending on the chirp mass of the binary. We use this upper limit to derive astrophysical constraints on two phenomenological models that could produce subsolar-mass compact objects. One is an isotropic distribution of equal-mass primordial black holes. Using this model, we find that the fraction of dark matter in primordial black holes in the mass range 0.2  M_{⊙}<m_{PBH}<1.0  M_{⊙} is f_{PBH}≡Ω_{PBH}/Ω_{DM}≲6%. This improves existing constraints on primordial black hole abundance by a factor of ∼3. The other is a dissipative dark matter model, in which fermionic dark matter can collapse and form black holes. The upper limit on the fraction of dark matter black holes depends on the minimum mass of the black holes that can be formed: the most constraining result is obtained at M_{min}=1  M_{⊙}, where f_{DBH}≡Ω_{DBH}/Ω_{DM}≲0.003%. These are the first constraints placed on dissipative dark models by subsolar-mass analyses.

Impact of Postoperative ABG Analysis and ICU Weaning Protocol in Surgical Outcome of Atlanto-Axial Dislocation: It's not the Towering Sail, but the Unseen Wind that Moves the Ship

Background

The outcome in patients of atlanto-axial dislocation (AAD) depends on multiple factors like preoperative optimization, intraoperative distractio and cord manipulation. Certain unfocussed factors such as respiratory reserve and compensatory acclimatization to hypoxia warrant consideration.

Aims

The purpose of this study is to find the association of postoperative arterial blood gas (ABG) analysis and respiratory reserve in patients of AAD with clinical outcome.

Study Design

We retrospectively analyzed the available records of patients, operated for AAD, at our institute (n = 66), from January 2014 to November 2018.

Materials and Methods

Preoperative pulmonary function test (PFT) and the postoperative ABG analysis was noted. Timing of extubation, duration of intensive care unit (ICU) stays, and clinical outcomes (Nurick grade) were noted from the inpatient record and the last outpatient follow up. An independent t-test and analysis of variance were used to find significance.

Results

In total, 41% (n = 27) patients had body mass index of less than 18.5, and 50% (n = 33) had breath holding time of less than 20 minutes. There was improvement in mean Nurick grade from 3.17 ± 0.8 to 2.76 ± 0.7 in follow up. A trend suggesting that patients with poor preoperative PFT has more ICU duration and worse outcome. In patients with mild acid-base disorders, extubation was possible within 24 hours. Out of 26 patients with ICU duration less than 2 days, 23 patients had "good" outcome, whereas ten out of 40 patients with ICU duration of more than or equal to 2 days had "bad" outcome (P = 0.00).

Conclusion

Patients having moderate to severe primary or mixed acid-base disorder have a probability of re-intubation or delayed extubation. A strong correlation was seen with the novel grading system (grade >6 had worse outcome).

An Institutional Experience and Literature Review on Iatrogenic Major Vascular Injury in Neurosurgery: Proposal of a Management Algorithm

Background

Major vessel injury is among the most dreaded complications of any neurosurgical procedure. Once intraoperatively tamponaded, it can present in the form of pseudoaneurysm, dissecting aneurysm or complete occlusion of vessel. These injuries are often associated with very high morbidity and mortality. The literature available on this topic is limited and our understanding remains limited.

Objective

In this article, we present our surgical experience with iatrogenic aneurysms and present a review of literature.

Methods and Material

We conducted a retrospective analysis of all patients with major vessel injury during surgery from a prospectively maintained database from January 2012 to February 2020.

Results

A total of 15 patients developed iatrogenic aneurysms following a major vessel injury during various neurosurgical procedures. The most common vessel injured was vertebral artery (n = 9) in craniovertebral junction (CVJ) anomalies and ossification of posterior longitudinal ligament (OPLL) followed by internal carotid artery injury (n = 5) in sellar and parasellar pathologies. One patient developed basilar artery injury during endoscopic third ventriculostomy (ETV). Eight patients had pseudoaneurysm and seven had dissecting aneurysm with or without complete thrombosis of the involved artery. A total of two patients died after vascular injury and remaining thirteen patients survived and discharged.

Conclusions

The adage "prevention is better than cure" applies most aptly in such cases. Any major vessel injury should be followed by immediate angiography and subsequent early management. The endovascular management is more favorable as these aneurysms are difficult to clip due to the absence of a neck and fragile wall.

Facile synthesized zinc oxide nanorod film humidity sensor based on variation in optical transmissivity

Variation in the transmitted light intensity from metal oxide thin films with moisture content provides a great opportunity to use them for humidity sensing. Herein, we have developed a novel and simple humidity sensor based on ZnO nanorod (ZNR) thin films which work as transmission-based sensing elements in an in-house fabricated sensing setup. The ZNR sensing element shows excellent linear sensing performance in the relative humidity (RH) range 10-90% and does not show any hysteresis. A maximum change in optical power of ∼95 μW is observed with the change in RH in the range 10-90%, for the sample with the smallest crystallite size (ZNR1) and highest pore diameter of the ZNR film. Also, a maximum sensitivity of 1.104 μW/% RH is observed for the ZNR1 sample which drops to 0.604 μW/% RH for the highest crystallite size sample (ZNR4). The presence of oxygen vacancies and the micro-porous nature of the film allow the absorption of water vapour on the film which deflects light at different angles that vary with the moisture content. The experimental results suggest that the ZNR film with a smaller crystallite size and larger pore diameter is more sensitive for humidity measurements. Further, an improved sensing performance is perceived in ZNRs because of the larger surface area of the nanorods. The ZNR based sensing elements do not suffer from ageing effects and exhibit high repeatability (88.74%). Further, the humidity sensor has a response time of 62 seconds and recovery time of 100 seconds which can be considered as a fairly quick response.

Cerebellopontine Angle Epidermoids: Comparative Results of Microscopic and Endoscopic Excision Using the Retromastoid Approach”

Background Densely packed neurovascular structures, often times inseparable capsular adhesions and sometimes a multicompartmental tumor extension, make surgical excision of cerebellopontine angle epidermoids (CPEs) a challenging task. A simultaneous or an exclusive endoscopic visualization has added a new dimension to the classical microscopic approaches to these tumors recently.

Methods Eighty-six patients (age: 31.6 ± 11.7 years, M:F = 1:1) were included. Nineteen patients (22.1%) had a multicompartmental tumor. Tumor extension was classified into five subtypes. Sixty-two patients underwent a pure microscopic approach (72%) out of which 10 patients (16%) underwent an endoscope-assisted surgery (11.6%) and 24 patients (28%) underwent an endoscope-controlled excision. Surgical outcomes were retrospectively analyzed.

Results Headache (53.4%), hearing loss (46.5%), and trigeminal neuralgia (41.8%) were the leading symptoms. Interestingly, 21% of the patients had at least one preexisting cranial nerve deficit. Endoscopic assistance helped in removing an unseen tumor lobule in 3 of 10 patients (30%). Pure endoscopic approach significantly reduced the hospital stay from 9.2 to 7.3 days (p = 0.012), and had a statistically insignificant yet a clearly noticeable lesser incidence of subtotal tumor excision (0 vs. 10%, p = 0.18) with comparable cranial nerve deficits but with a higher postoperative cerebrospinal fluid (CSF) leak rate (29% vs. 4.8%, p = 0.004).

Conclusion Endoscope assistance in CPE surgery is a useful addition to conventional microscopic retromastoid approach. Pure endoscopic excision in CPE is feasible, associated with a lesser duration of hospital stay, better extent of excision in selected cases, and it has a comparable cranial nerve morbidity profile albeit with a higher rate of CSF leak.

Unusual High Hardness and Load-Dependent Mechanical Characteristics of Hydrogenated Carbon-Nitrogen Hybrid Films

Mechanical components are exposed to a rigorous environment in a number of applications including engineering, aerospace, and automobiles. Thus, their service lifetime and reliability are always on the verge of risk. Protective coatings with high hardness are required to enhance their service lifetime and minimize the replacement cost and waste burden. Hydrogenated amorphous carbon including nitrogen-incorporated films, that are commonly deposited by plasma-enhanced chemical vapor deposition, are widely used for commercial protective coating applications. However, their mechanical hardness still falls into the moderate hard regime. This needs to be substantially enhanced for advanced applications. Here, we report the synthesis of very hard nanostructured hydrogenated carbon-nitrogen hybrid (n-C:H:N) films. The optimized n-C:H:N film displays a hardness of about 36 GPa, elastic modulus of 360 GPa, and reasonably good elastic recovery (ER) of 62.7%. The mechanical properties of n-C:H:N films are further tailored when nitrogen pressure is tuned during the growth. The realized remarkably improved mechanical properties are correlated with the films' structural properties and experimental growth conditions. We also conducted density functional theory calculations that show the trend for the elastic modulus of the amorphous carbon films with varying nitrogen concentrations matches well with experimentally measured values. Finally, we probed load-dependent mechanical properties of n-C:H:N films and found an anomalous behavior; some of the mechanical parameters, for instance, ER, reveal an irregular trend with indentation load, which we explain in the framework of the film-substrate composite concept. Overall, this work uncovers many unknown and exciting mechanical phenomena that could pave the way for new technological developments.

An alternate surgical treatment of giant serpentine aneurysm of the middle cerebral artery: Resection and End-to-End anastomosis

A section of giant intracranial aneurysms can develop serpentine morphology, secondary to a peculiar near-complete intra-aneurysmal thrombosis. The resulting complex angioarchitecture, along with the atypical clinical presentations (mass effect/distal ischemia) seen, makes management of such aneurysms technically challenging. Such aneurysms are notoriously not amenable to endovascular treatment, and hence, the only remaining treatment option is a tailored microsurgical procedure (clipping/parent vessel occlusion or reconstruction/trapping/aneurysmorrhaphy) accompanied by a safety bypass (high-flow/low-flow/in-situ bypass, depending on distal circulation's dependence on proximal trunk with reference to aneurysm). Microsurgical plan can be executed either in a single-stage or in two stages (bypass followed by later-date aneurysm treatment). Superficial temporal artery - middle cerebral artery (STA-MCA) bypass with/followed by aneurysm trapping-decompression is the most routinely performed microsurgical procedure for such aneurysms. We herein present an operative video illustrating an alternate surgical treatment of one such giant serpentine aneurysm of the MCA: Resection and End-to-End anastomosis. A 20-year-old boy underwent microsurgery for a giant right MCA serpentine aneurysm. In view of the poor distal flow in the ipsilateral MCA territory, an STA-MCA bypass with aneurysm trapping-decompression was planned. Intraoperatively, the presence of a stretched and elongated ipsilateral MCA (secondary to aneurysm's mass effect), plus the relatively narrow neck of the thrombosed aneurysm, provided us a rare opportunity to execute the above-mentioned alternate treatment. Intra and postoperative angiography confirmed the anastomosis patency. The patient made an uneventful recovery. This can save operating time, eliminate donor artery-related morbidity, and offer a surgical alternate to the conventional strategy of STA-MCA bypass.

Hybrid Anterior Clinoidectomy in the Clipping of Paraclinoid Aneurysms: Technique, Utility and Case Illustration

BACKGROUND

Anterior clinoidectomy for aneurysm clipping is generally performed intradurally. Despite obvious advantages, accidental drill slippage or indirect damage from heat and bone dust remain major drawbacks.

OBJECTIVE

To demonstrate the surgical technique and utility of a combined extra- and intra-dural clinoidectomy in the clipping of dorsal wall paraclinoid internal carotid artery aneurysm.

MATERIAL AND METHODS

A case of dorsal wall paraclinoid aneurysm which was stuck to the anterior clinoid process on preoperative angiogram is presented. The surgical technique is shown stepwise, and the intricacies of the technique are described.

RESULTS

The hybrid clinoidectomy allowed for proper delineation of the aneurysm, mobilization of the optic nerve and intracranial proximal control on the clinoidal segment by dint of "apparent" intracranial ICA lengthening. This allowed the aneurysm to be clipped successfully and the patient made an uneventful recovery.

CONCLUSION

Hybrid clinoidectomy is a useful technique and must be learnt.

The Spectrum of Invasive Fungal Sinusitis in COVID-19 Patients: Experience from a Tertiary Care Referral Center in Northern India

This study aimed to determine the patient demographics, risk factors, which include comorbidities, medications used to treat COVID-19, and presenting symptoms and signs, and the management outcome of COVID-19-associated invasive fungal sinusitis. A retrospective, propensity score-matched, comparative study was conducted at a tertiary care center, involving 124 patients with invasive fungal sinusitis admitted between April 2021 and September 2021, suffering from or having a history of COVID-19 infection. Among the 124 patients, 87 were male, and 37 were female. A total of 72.6% of patients received steroids, while 73.4% received antibiotics, and 55.6% received oxygen during COVID-19 management. The most common comorbidities were diabetes mellitus (83.9%) and hypertension (30.6%). A total of 92.2% had mucor, 16.9% had aspergillus, 12.9% had both, and one patient had hyalohyphomycosis on fungal smear and culture. The comparative study showed the significant role of serum ferritin, glycemic control, steroid use, and duration in COVID-19-associated invasive fungal disease (p < 0.001). Headache and facial pain (68, 54.8%) were the most common symptoms. The most involved sinonasal site was the maxillary sinus (90, 72.6%). The overall survival rate at the three-month follow-up was 79.9%. COVID-19-related aggressive inflammatory response, uncontrolled glycemic level, and rampant use of steroids are the most important predisposing factors in developing COVID-19-associated invasive fungal sinusitis.

Lesional Temporal Lobe Epilepsy: Does the “Uncommon” Differ from the Common?

Objectives This study aims to evaluate the subgroup consisting of uncommon pathological entities presenting with temporal lobe epilepsy (TLE).

Methodology Twenty-four consecutively operated patients of lesional temporal lobe epilepsy were included in the study. Eleven cases were identified that had pathologies implicated as “uncommon” in previously done studies on the pathology of TLE. A subgroup analysis consisting of these uncommon lesions was done for clinical presentation and seizure outcome. The seizure outcome was assessed in terms of Engel and International League Against Epilepsy (ILAE) classification.

Results Nine different pathological entities were identified within the study group. The mean age at surgery was 18.6 years (range 2–30 years). The mean duration of epilepsy was 48.3 months and the average duration of follow-up was 39.2months. All patients had seizures as the only complaint except three. Three patients had focal-aware seizures, two had focal motor onset, and the rest all had focal-unaware seizures. Seven patients were seizure free and the average age at diagnosis for these patients was 15.4 years (range 2–24 years.). The duration of seizure in the postoperative seizure-free group was 29.7 months and it was 81 months for the other group. All the patients with persistent postoperative seizures had focal-unaware seizures preoperatively.

Conclusion Despite the small and heterogeneous nature of this subgroup of uncommon lesions causing temporal lobe epilepsy, the clinical presentation, prognostic factors, and seizure outcome are similar to the cohort of common pathologies, including mesial temporal sclerosis.

Clinical Utility of Intravascular Ultrasound (IVUS) in Carotid Artery Interventions: A Systematic Review and Meta-analysis

BACKGROUND

Carotid plaque morphology plays an important role in determining outcome of carotid artery stenting (CAS). Intravascular ultrasound (IVUS) and its extension VH (Virtual Histology)-IVUS evaluate plaque characteristics in real time and guide decision making during stenting. To date, there is no consensus about indications of IVUS and its validated methods. This systematic review and meta-analysis aims to evaluate the clinical utility of IVUS in carotid artery interventions (CAS) and develop a future consensus for research and practice parameters.

METHODS

A systematic review and meta-analysis was performed of the English literature articles published till February 2021. Studies reporting on IVUS parameters and findings and also its performance compared with other imaging modalities were included in review. Pooled prevalence with 95% confidence intervals (CI) was calculated. The statistical analysis was conducted in R version 3.6.2.

RESULTS

A total of 2015 patients from 29 studies were included. Proportional meta-analysis was performed on 1566 patients from 11 studies. In 9 studies, stroke/transient ischemic attack (TIA) had a pooled prevalence of 4% (95% CI 3%-5%) while asymptomatic stroke had a pooled prevalence of 46% (95% CI 31%-62%) in 4 studies following IVUS. Two studies reported that IVUS detected more plaque protrusion compared with angiography (n=33/396 vs 11/396). IVUS led to stent type or size change in 8 of 48 cases which were missed on angiography in 3 other studies. Concordance between VH-IVUS and true histology was good at 80% to 85% reported in 2 studies.

CONCLUSIONS

This systematic review and meta-analysis showed, though IVUS fared better to computed tomography (CT)/magnetic resonance (MR) angiography for better stent selection during CAS, with low to moderate risk of bias in the studies included. However, large scale, preferably randomized controlled studies are needed to predict its role in determining clinical outcome.

Angstrom-Scale Transparent Overcoats: Interfacial Nitrogen-Driven Atomic Intermingling Promotes Lubricity and Surface Protection of Ultrathin Carbon

Lubricity, a phenomenon which enables the ease of motion of objects, and wear resistance, which minimizes material damage or degradation, are important fundamental characteristics for sustainable technology developments. Ultrathin coatings that promote lubricity and wear resistance are of huge importance for a number of applications, including magnetic storage and micro-/nanoelectromechanical systems. Conventional ultrathin coatings have, however, reached their limit. Graphene-based materials that have shown promise to reduce friction and wear have many intrinsic limitations such as high temperature and substrate-specific growth. To address these concerns, a great deal of research is currently ongoing to optimize graphene-based materials. Here we discover that angstrom-thick carbon (8 Å) significantly reduces interfacial friction and wear. This lubricant shows ultrahigh optical transparency and can be directly deposited on a wide range of surfaces at room temperature. Experiments combined with molecular dynamics simulations reveal that the lubricating efficacy of 8 Å carbon is further improved via interfacial nitrogen.

Association between plant nutrients, the development of Huanglongbing and abnormal growth symptoms in navel orange

Huanglongbing (HLB) causes extensive damage in citrus orchards worldwide. Symptoms include blotchy mottle leaf (BML) and little leaf chlorosis (LLC), and nutrient deficiency usually occurs concurrently. However, the relationship between plant mineral content and infection with Candidatus Liberibacter asiaticus (CLas) is not clearly established. We sampled 7-month-old autumn shoots with three characteristic phenotypes, asymptomatic leaf (AL), BML and LLC, representing HLB disease progression, and further divided samples into CLas-infected and uninfected based on PCR analysis. HLB infection decreased transfer coefficients of Mg and K from leaf to phloem tissues through regulation of the transporter genes Cs3g03790.1 and PtrMGT5, increasing the content of leaf Mg and K. HLB infection also decreased leaf Zn, xylem Ca and phloem Ca and Zn content. Leaf Ca, Mg, Zn and B content decreased while leaf K content increased significantly as symptoms progressed from AL to LLC. The transport of P from leaf to phloem tissue, as evaluated by the transfer coefficient, was regulated by the transporter CsiPT2, resulting in irregular levels of leaf P. Our results provide insights into the nutrient dynamics in Citrus in response to CLas infection and the progression of HLB symptoms.

Tanycytic ependymoma: highlighting challenges in radio-pathological diagnosis

Background

Tanycytic ependymoma (TE) (WHO grade II) is a rare and morphologically distinct variant of ependymoma with only 77 cases reported worldwide so far. Variable clinical and radio-pathological features lead to misdiagnosis as WHO grade 1 tumors. On imaging, differentials of either schwannoma, meningioma, low-grade glial (like angiocentric glioma), or myxopapillary ependymoma are considered. In this study, we aim to discuss clinical, radiological, and pathological features of TE from our archives.

Method

We report clinicopathological aspects of six cases of TE from archives of tertiary care center between 2016 and 2018. Detailed histological assessment in terms of adequate tissue sampling and immunohistochemistry was done for each case.

Result

The patient's age ranged between 10 and 53 years with a slight male predilection. Intraspinal location was seen in two cases (intramedullary and extramedullary), three cases were cervicomedullary (intramedullary), and one was intracranial. One case was associated with neurofibromatosis type 2. Four cases mimicked as either schwannoma or low-grade glial tumor on squash smears. On imaging, ependymoma as differential was kept in only two cases and misclassified remaining either as low-grade glial or schwannoma.

Discussion

In initial published reports, the spine is the most common site (50.4%) followed by intracranial (36.4%) and cervicomedullary (3.9%). They have also highlighted the challenges in diagnosing them intraoperatively and radiologically. Treatment is similar to conventional ependymoma if diagnosed accurately. A multidisciplinary approach with the integration of neurosurgeon, neuroradiologist, and neuropathologist is required for accurate diagnosis and better treatment of patients.

Trends in clinico-epidemiology profile of surgically operated glioma patients in a tertiary care center over 12 years—through the looking glass!

Background

Hospital-based cancer registries can provide information on the magnitude and distribution of cancers in a given hospital. Hospital-based brain tumor registry data, focusing on glioma, from a tertiary care rural neurological center is lacking in the scientific literature. This data can be useful in understanding the need for research and funding required for these specific brain tumors.

Data of patients operated for glioma, at our institute, was collected between January 2004 and December 2015. Patients’ clinical details and histopathological diagnosis were recorded. Data were analyzed and compared with that of previously published literature, and inferences were drawn on patterns of reporting and epidemiology.

Results

A total of 1450 cases of glioma, with a mean age of 39.3 (± 17.36 SD) years with males (66.6%) comprising more population as compared to females. Majority of patients 70.8% (n = 1027) belong to the economically active age group of country (18–60 years). Majority of cases (41.4%) were glioblastoma with the next common tumor (22.8%) being diffuse astrocytoma (n = 331) followed by pilocytic astrocytoma (6.2%) and oligodendroglioma (4.5%) in that order. While our data followed similar trends with other Indian data the average age of glioma was a decade younger to what is quoted earlier in Indian and international studies.

Conclusion

This data for glioma gives a glimpse of the prevalence of this tumor in a primarily rural population and highlights the need for a National Brain Tumor Registry with the need for the development of evidence-based policymaking and enhanced research into this particular ailment.

Contribution of Indian researchers in high impact periodontal journals: a bibliometric analysis of last three years

Bibliometric Analysis researches and analyses the quantitative data derived from scientific publications through the empirical evidence of scientific activity generated by collaborating authors through the final product of their research: the scientific article. In scientific society, the concept of impact factor is probably the most widely used in bibliometric construction. To assess the scientometrics of three high-impact factor periodontal journals and identify the contribution of India in these most productive journals over three years (Jan 2018 - Dec 2020) and to know the most influential topics researched. A retrospective observational study was conducted for the Journal of Clinical Periodontology, Journal of Periodontology, and Journal of Periodontal Research. All issues of 2018, 2019, and 2020 were electronically and hand searched for the following parameters: Number of papers, affiliated organizations, and countries, topics reported, and contribution of Indian authors. The data were organized and analyzed with descriptive statistics using SPSS software (version 21.0). In total 469 articles were published by Journal of Periodontology, followed by 454 articles in Journal of Clinical Periodontology and 287 articles in Journal of Periodontal Research. In all the three journals, China had the maximum contributions, succeeded by USA. India has published maximum number of articles in the Journal of Periodontal Research. When analysed, although less as compared to the western counterparts, an increasing trend in the publications is seen in case of India.

Calvarial Lesions: A Tertiary Centre's Experience Over Fifteen Years

Background

The human calvaria harbors a variety of pathology and majority of them are incidentally noticed as painless swelling. The aim of the present study is to describe the histopathological subtypes of calvarial lesions, their management and factors affecting their surgical outcome at a tertiary care referral center.

Material and Methods

All patients who underwent excision of the calvarial lesions over the last 15 years (from January 2005 to July 2019) were included in this study. Patients having calvarial pathology of infective origin and recurrent lesions were excluded. Any patient with multiple calvarial lesions who have been operated more than one time for same histopathological diagnosis was counted as one patient. We studied Karnofsky Performance Status (KPS) scores and radiological changes at 3-month follow up.

Results

Total 65 patients were recruited in this retrospective observational study. The median age of patients in the study was 29 years (range: 8 years to 68 years). Fibrous dysplasia 20 (30.7%) was the commonest lesion while metastatic thyroid carcinoma 3 (4.6%) was the most common malignant pathology. Complete excision was performed in 51 (78.5%) of patients while in 14 (21.5%) cases, subtotal or near total decompression were achieved. After three months of surgery, there was significant improvement in the KPS score (P < 0.00001). Duration of follow up ranges from 6 months to 5 years with 4 mortality in the study.

Conclusions

Most of the calvarial tumors were benign and surgically addressable. The malignant lesions were scattered with diverse underlying pathology and required individualized holistic approach.

Does Socioeconomic Status Have an Association with Cranio-vertebral Anomalies: A Step Toward Healing the Curse!

Background

The etiological or causal factors of pediatric craniovertebral junction anomalies (CVJA) are still unknown. The disease bears a major proportion of economic and social burdens over a developing country like ours. This article aims to highlight an important modifiable factor that may prove to have a critical causal relationship with disease incidence.

Materials and Methods

This is a cross-sectional, single-institutional study, wherein the socioeconomic status (SES) of all the operated pediatric patients of CVJA, between 2014 and 2019, was studied. Variables including the patient's age, sex, residence status (rural or urban), perioperative data, length of stay, follow-up, and the time between revision surgery (if required) and clinical presentation were noted. Data regarding average household and type of family (nuclear or joint) were also enquired.

Results

Sixty-six patients (M:F 56:10) with a mean age of 13.14 ± 3.44 years were included. The mean annual family income was 11.1 ± 12.1 thousands. 43.9% belonged to joint family; according to Kuppuswami and Prasad scale, 42.4% of patients belong to lower class, while 20 patients belong to lower middle class, and 14 patients belong to the below poverty line category. Neither the SES of patient nor rural-urban background affected the surgical outcome. The mean follow-up of patients in our study was 42.3 ± 23.0 months and 83.3% had a good outcome.

Discussion

Patients operated for CVJ anomaly in the authors' institution mainly come from the lower socioeconomic groups. The present study raises several important questions like nutritional deficiencies in reproductive age group females leading to a cascade of events as a causal factor.

Efficacy of Silicone Conduit in the Rat Sciatic Nerve Repair Model: Journey of a Thousand Miles

Background

A lot of options have been tried for bridging the two ends of the injured nerves. Researchers have used decellularized nerve grafts, artificial materials and even nerve growth factors to augment functional recovery. These materials are either costly or inaccessible in developing world.

Objective

The study aimed to evaluate the efficacy of the silicone conduit in a rat sciatic nerve injury model.

Materials and Methods

24 healthy Sprague-Dawley (SD) rats (250-300 grams; 8-10 weeks) were used and right sciatic nerve was exposed; transected and re-anastomosed by two different methods in 16 rats. In control group, n = 8 (Group I) the sciatic nerve was untouched; Group II (reverse nerve anastomosis, n = 8): 1-centimeter of nerve was cut and re-anastomosed by using 10-0 monofilament suture; Group III (silicone conduit, n = 8) 1-centimeter nerve segment was cut, replaced by silicone conduit and supplemented by fibrin glue]. Evaluation of nerve recovery was done functionally (pain threshold and sciatic functional index) over 3 months and histologically and electron microscopically.

Results

Functional results showed a trend of clinical improvement in Group III and II but recovery was poor and never reached up to normal. Histopathological and electron microscopic results showed an incomplete axonal regeneration in Groups II and III. Psychological analyses showed that no outwards signs of stress were present and none of the rats showed paw biting and teeth chattering.

Conclusion

The silicone conduit graft may be an economical and effective alternative to presently available interposition grafts, however for short segments only.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Constraints on Cosmic Strings Using Data from the Third Advanced LIGO-Virgo Observing Run

We search for gravitational-wave signals produced by cosmic strings in the Advanced LIGO and Virgo full O3 dataset. Search results are presented for gravitational waves produced by cosmic string loop features such as cusps, kinks, and, for the first time, kink-kink collisions. A template-based search for short-duration transient signals does not yield a detection. We also use the stochastic gravitational-wave background energy density upper limits derived from the O3 data to constrain the cosmic string tension Gμ as a function of the number of kinks, or the number of cusps, for two cosmic string loop distribution models. Additionally, we develop and test a third model that interpolates between these two models. Our results improve upon the previous LIGO-Virgo constraints on Gμ by 1 to 2 orders of magnitude depending on the model that is tested. In particular, for the one-loop distribution model, we set the most competitive constraints to date: Gμ≲4×10^{-15}. In the case of cosmic strings formed at the end of inflation in the context of grand unified theories, these results challenge simple inflationary models.

Clinicoradiological Features and Treatment Outcome of Supratentorial Intraparenchymal Epidermoid Cyst: A Report of Five Cases and Literature Review

Objectives  Intraparenchymal epidermoid cysts (IECs) are rare lesions. They represent less than 1% of the intracranial epidermoid cysts. The supratentorial IEC is a clinically and prognostically distinct subset. Given the rarity, most of the articles are case reports. We present a series of five cases of supratentorial IEC to characterize their clinical presentation and outcome, with emphasis on the surgical features.

Materials and Methods  We searched our database for all cases of intracranial epidermoid cysts operated between January 2005 and January 2020. Five patients were identified having IEC from the hospital information system and the neurosurgical operation record book. Standard craniotomy and decompression of the lesion were performed in all these patients. Standard postoperative care includes computed tomography scan of head on the day of surgery and magnetic resonance imaging of brain after 6 weeks to look for the residual lesion, if any. Subsequent follow-up visits in outpatient department to look for resolution of the presurgical symptoms.

Results  The mean age of the patients in our series was 28.8 years (range: 28–40 years.). All the five patients were male. Four patients had IEC involving frontal lobe and one in parietal lobe with a small occipital lobe extension. Seizure was the most common presenting complaint followed by headache. Complete excision was achieved in all the cases. All the three patients with seizure attained seizure freedom postlesionectomy. Focal neurological deficits resolved gradually in postoperative period. There was no recurrence of lesion during follow-up.

Conclusion  Supratentorial IEC most commonly affects young males, involve frontal lobe and present clinically with seizure. Complete surgical excision offers best outcome in the form of remission of seizure disorder.

C3 segmental vertebral artery and its surgical implication in craniovertebral junction anomalies: Insights from two cases

A spectrum of vertebral artery (VA) anomalies have been described with or without an associated congenital craniovertebral junction (CVJ) anomalies. C3 segmental VA, where the VA enters the dura at the level of C2/3 intervertebral foramen is an extremely rare anomaly. We report two cases of congenital CVJ anomaly (irreducible in one with C2/3 fusion and reducible in the other; without any subaxial fusion but with articular agenesis at C2/3 joint on the anomalous artery side). Computed tomographic angiography revealed intraspinal intradural entry of VA through the C2/3 intervertebral foramen on the right side with the contralateral artery found crossing the atlanto-axial joint. Both the patients underwent posterior approach and C2 was spared from instrumentation in both cases. Postoperatively, the patient with irreducible dislocation recovered well while the patient with reducible dislocation expired, possibly secondary to the thrombosis of the dominant VA from C2/3 foraminal encroachment. C3 segmental VA may be advantageous in aggressively exposing the C1/2 joint but instrumentation of C2 or C3 needs caution in view of the possibility of VA injury. Our experience shows that VA may be endangered even while exposing and protecting the artery. For such cases, we recommend posterior decompression of the C2/3 neural foramen during instrumentation in the absence of associated C2/3 fusion, as an abnormal joint morphology of C2/3 indicates a C2/3 instability.

Type I Chiari Malformation Without Concomitant Bony Instability: Assessment of Different Surgical Procedures and Outcomes in 73 Patients

OBJECTIVE

Posterior fossa decompression is the treatment of choice in type 1 Chiari malformation (CM-1) without bony instability. Although surgical fixation has been recommended by a few authors recently, comparative studies to evaluate these treatment strategies using objective outcome tools are lacking.

METHODS

Seventy-three patients with pure CM-1 (posterior fossa bony decompression [PFBD], n = 21; posterior fossa bony and dural decompression [PFBDD], n = 40; and posterior fixation [PF], n = 12) underwent a postoperative outcome assessment using Chicago Chiari Outcome Score (CCOS). Logistic regression analysis detected predictors of an unfavorable outcome.

RESULTS

Minimally symptomatic patients generally underwent a PFBD while most of the clinically severe patients underwent a PFBDD (p = 0.049). The mean CCOS score at discharge was highest in the PF (12.0 ± 1.41) and lowest in PFBDD group (10.98 ± 1.73, p = 0.087). Patients with minimal preoperative clinical disease severity (adjusted odds ratio [AOR], 4.58; 95% confidence interval [CI], 1.29-16.31) and PFBDD (AOR, 7.56; 95% CI, 1.70-33.68) represented risks for an unfavorable short-term postoperative outcome. Though long-term outcomes (CCOS) did not differ among the 3 groups (p = 0.615), PFBD group showed the best long-term improvements (mean follow-up CCOS, 13.71 ± 0.95), PFBDD group improved to a comparable degree despite a poorer short-term outcome while PF had the lowest scores. Late deteriorations (n = 3, 4.1%) occurred in the PFBDD group.

CONCLUSION

Minimally symptomatic patients and PFBDD predict a poor short-term postoperative outcome. PFBD appears to be a durable procedure while PFBDD group is marred by complications and late deteriorations. PF does not provide any better results than posterior fossa decompression alone in the long run.

Synthesis, biological evaluation, and molecular docking study of some new rohitukine analogs as protein tyrosine phosphatase 1B inhibitors

Rohitukine (RH) was extracted from the stem bark of Dysoxylum binectariferum Hook. It was derivatized to different arylsulphanmides by treating with the corresponding aryl sulphonyl chlorides. These derivatives were tested in-vitro on protein tyrosine phosphatase 1B (PTP1B) inhibition. Among these the active compounds K2, K3, K5, and K8 significantly inhibited the PTP1B by 51.3%, 65.6%, 71.9%, and 55.9% respectively at 10 µg/ml, the results were also supported by in-silico docking experiments. The most potent compound K5 was analyzed for antidiabetic and antidyslipidemic activity in vivo. It showed a marked reduction in blood glucose level (random and fasting) and serum insulin level in db/db mice. It improved glucose intolerance as ascertained by the oral glucose tolerance test (OGTT). These NCEs (New Chemical Entities) also lowered cholesterol and triglyceride profiles while improved high-density lipoprotein cholesterol in db/db mice. The K5 was further evaluated for antiadipogenic activity on MDI (Methylisobutylxanthine, dexamethasone, and insulin)-induced adipogenesis. where it significantly inhibited MDI-induced adipogenesis in 3 T3-L1 preadipocytes, at 10 µM and 20 µM concentration. These results were compared with the parent compound RH which inhibited 35% and 45% lipid accumulation while the RH analog K5 inhibited the lipid accumulation by 41% and 51% at 10 and 20 µM concentration, respectively. These results well corroborated with in-silico studies.

ESTIMATION OF ENTRANCE SURFACE AIR KERMA IN DIGITAL RADIOGRAPHIC EXAMINATIONS

PURPOSE

Contribution of radiation doses from medical X-ray examination to collective dose is significant. Unusually, high doses may increase the risk of stochastic effects of radiations. Therefore, radiation dose assessment was performed in 241 digital X-ray examinations in the study and was compared with published dose reference levels (DRLs).

METHODS

Entrance surface air kerma (ESAK) was calculated in chest PA, cervical AP/Lat, abdomen AP, lumbar AP/Lat and pelvis AP digital radiographic examinations (119 male and 122 female) following the International Atomic Energy Agency recommended protocol. Initially, 270 digital examinations were selected, reject analysis was performed and final 241 examinations were enrolled in the study for dose calculations. The exposure parameters and X-ray tube output were used for dose calculations. Effective doses were estimated with the help of conversion coefficients from ICRP 103.

RESULTS

Median ESAK (mGy) and associated effective doses obtained were cervical spine AP (1.30 mGy, 0.045 mSv), cervical spine Lat (0.25 mGy, 0.005 mSv), chest PA (0.11 mGy, 0.014 mSv), abdomen AP (0.90 mGy, 0.118 mSv), lumbar spine AP (1.52 mGy, 0.177 mSv), lumbar spine Lat (7.76 mGy, 0.209 mSv) and pelvis AP (0.82 mGy, 0.081 mSv). Results were compared with the studies of UK, Oman, India and Canada.

CONCLUSION

The calculated ESAK and effective dose values were less than or close to previously published literature except for cervical spine AP and lumbar spine Lat. The results reinforce the need for radiation protection optimization, improving examination techniques and appropriate use of automatic exposure control in digital radiography. ESAK values reported in this study could further contribute to establishing local DRLs, regional DRLs and national DRLs.

Potential of graphene-based materials to combat COVID-19: properties, perspectives, and prospects

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a new virus in the coronavirus family that causes coronavirus disease (COVID-19), emerges as a big threat to the human race. To date, there is no medicine and vaccine available for COVID-19 treatment. While the development of medicines and vaccines are essentially and urgently required, what is also extremely important is the repurposing of smart materials to design effective systems for combating COVID-19. Graphene and graphene-related materials (GRMs) exhibit extraordinary physicochemical, electrical, optical, antiviral, antimicrobial, and other fascinating properties that warrant them as potential candidates for designing and development of high-performance components and devices required for COVID-19 pandemic and other futuristic calamities. In this article, we discuss the potential of graphene and GRMs for healthcare applications and how they may contribute to fighting against COVID-19.

Venous corridors in gravity-assisted retractor-less occipito-transtentorial approach - Our experience of an avenue through the tentacles of pod

Background:

Occipital transtentorial approach for selected posterior third ventricular or retrosplenium region tumors provides an ergonomic and safe access. Over centuries, the opponents of this approach highlight the problem of postoperative visual field defect, related to the retraction of occipital lobe. The aim was to describe the surgical nuances of gravity-assisted retractor-less occipital-transtentorial approach (GAROTA) as a modification of originally described GAROTA to minimize the complications with a similar ease of surgery.

Methods:

In this study, we have retrospectively analyzed our prospectively maintained surgical databases of patients operated by occipito-transtentorial from 2015 to 2019. Demographic variables, preoperative and postoperative neurological deficits (especially visual field defect) were analyzed. Radiological data included relation of veins with tumor, presence of hydrocephalus, size, and extent of lesion.

Results:

Fifteen patients underwent GAROTA (right-sided extension, n = 7; left-sided extension, n = 4; and midline lesions, n = 4). Headaches (73.3%) and diplopia (40%) were the most common symptoms. No patient had any postoperative visual deficits in both short-term and long-term follow-up.

Conclusion:

A thorough anatomical knowledge of posterior third interhemispheric region in the semi-prone position is required for GAROTA. Meticulous arachnoid dissection around the deep venous complex and release of cerebrospinal fluid through the cisterns is required. Postoperative cortical vision loss may be prevented by following the key surgical principles in GAROTA.

A Prospective, Single-Blinded, Bicentric Study, and Literature Review to Assess the Need of C2-Ganglion Preservation - SAVIOUR's Criteria

Objective

Joint manipulation for craniovertebral junction instability is often hindered by the C2-ganglion (C2G). Our study aims to compare the surgical outcome among patients with or without C2G preservation and discuss the technical nuances.

Methods

We did a prospective, bicentric study and included all the operated patients with craniovertebral junction anomaly. The outcome was assessed by the Pain Numeric Rating Scale, Patient Satisfactions Score, and Stony Brook Scar Evaluation Scale. The fusion was assessed using Lenke fusion grade.

Results

One hundred seventy-one patients (88 in group A and 83 in group B) were included. The most common symptom was spastic quadriparesis (n = 165, 96.5%) with median Nurick grade 3.3. Thirteen patients had suboccipital numbness and 12 patients had paraesthesia. Mean blood loss in group A was 490 ± 96.2 mL and group B was 525 ± 45.7 mL; median operative time was 217.9 and 162.2 minutes in the groups A and B, respectively (p < 0.05). At the follow-up (median, 46.8 months), Lenke fusion grade A was achieved in 92.4% and grade B in 7.6%. A trend suggesting better functional outcomes (numbness, parestheisa, scar outcome, and postoperative ulcer formation) in group A was seen with all 6 patients, who underwent O-C2 fixation, developed pressure sore.

Conclusion

Our results support ganglion preservation, especially in the subset of patients where occipital plating is required. Although the study fails to show any statistical significance, we suggest that one should always start with an ‘intent’ of preservation as the functional outcome is better.