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Ben Ner D, Vainer I, Toh ST, Loh S, Shofel-Havakuk H, Alkan U. Simethicone use in drug-induced sleep endoscopy improves visibility. Sleep Breath 2023:10.1007/s11325-023-02963-5. [PMID: 38110601 DOI: 10.1007/s11325-023-02963-5] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 11/25/2023] [Accepted: 11/29/2023] [Indexed: 12/20/2023]
Abstract
PURPOSE To assess the effect of simethicone, a defoaming agent, on improving visibility during drug-induced sleep endoscopy (DISE) in obstructive sleep apnea (OSA). METHODS The study was a retrospective case-series study on patients with OSA who failed positive airway pressure (PAP) treatment. Patient parameters were recorded including age, BMI, neck and abdominal circumference, and apnea-hypopnea index (AHI). Comparisons were made between DISE procedures performed with and without the administration of simethicone. Visibility during DISE was independently graded by two surgeons, and inter-rater reliability was assessed. RESULTS Simethicone significantly improved DISE visibility (p = 0.03). "Best visibility" was achieved in 55% of cases with simethicone compared to 27% without simethicone (p = 0.02). Sub-analysis showed that only simethicone administration had a significant effect on visibility (p = 0.02). Inter-rater reliability between the grading surgeons was strong (Cohen-Kappa score 0.7, p < 0.001). CONCLUSION The findings suggest that simethicone enhances DISE visibility for OSA surgical planning. Further research should explore optimizing simethicone administration timing and the potential clinical implications for surgical outcomes and patient care.
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Affiliation(s)
- Daniel Ben Ner
- Department of Otolaryngology Head and Neck Surgery, Rabin Medical Center, Petah Tikva, Israel.
- The Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
| | - Igor Vainer
- Department of Otolaryngology Head and Neck Surgery, Rabin Medical Center, Petah Tikva, Israel
- The Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Song Tar Toh
- Department of Otorhinolaryngology-Head and Neck Surgery, Singapore General Hospital, Singapore, Singapore
- Singapore SingHealth Duke-NUS Sleep Centre, Singapore, Singapore
| | - Shaun Loh
- Department of Otorhinolaryngology-Head and Neck Surgery, Singapore General Hospital, Singapore, Singapore
- Singapore SingHealth Duke-NUS Sleep Centre, Singapore, Singapore
| | - Hagit Shofel-Havakuk
- Department of Otolaryngology Head and Neck Surgery, Rabin Medical Center, Petah Tikva, Israel
- The Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Uri Alkan
- Department of Otolaryngology Head and Neck Surgery, Rabin Medical Center, Petah Tikva, Israel
- The Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
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Lim JWL, Kwa C, Loh S, Yew WS. Delayed presentation of transdermal cyanide poisoning. Anaesth Rep 2023; 11:e12254. [PMID: 37937282 PMCID: PMC10626002 DOI: 10.1002/anr3.12254] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/06/2023] [Indexed: 11/09/2023] Open
Abstract
A 45-year-old man attended to a warehouse fire involving burning plastic, without wearing full protective equipment. He subsequently presented to hospital with shortness of breath and his trachea was intubated for airway protection due to initial concerns of inhalational injury. However, a post-intubation bronchoscopy was normal. The patient's serum lactate level was normal on admission but was increased when measured 14 h after the initial event and accompanied by a metabolic acidosis. Transdermal cyanide poisoning was suspected given this delayed biochemical presentation and the absence of another apparent cause. A handheld chemical detector detected a high level of toxins on the patient's skin. Clinical improvement was not observed after the first dose of intravenous hydroxocobalamin, which was administered before full body decontamination. After decontamination and the administration of a second dose of hydroxocobalamin, the patient's acid-base status rapidly improved and serum lactate level returned to normal. Clinicians should have a high index of suspicion for transdermal cyanide poisoning in patients presenting after exposure to a fire.
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Affiliation(s)
- J. W. L. Lim
- Department of AnaesthesiologySingapore General HospitalSingapore
| | - C. Kwa
- Department of AnaesthesiologySingapore General HospitalSingapore
| | - S. Loh
- Department of AnaesthesiologySingapore General HospitalSingapore
| | - W. S. Yew
- Department of AnaesthesiologySingapore General HospitalSingapore
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Yeo BSY, Koh JH, Ng ACW, Loh S, See A, Seow DCC, Toh ST. The association of obstructive sleep apnea with blood and cerebrospinal fluid biomarkers of Alzheimer's dementia - A systematic review and meta-analysis. Sleep Med Rev 2023; 70:101790. [PMID: 37245474 DOI: 10.1016/j.smrv.2023.101790] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 04/19/2023] [Accepted: 05/07/2023] [Indexed: 05/30/2023]
Abstract
Alzheimer's disease (AD) is the most common type of dementia and is characterized by the aggregation of extracellular amyloid-beta and intracellular hyperphosphorylation of tau proteins. Obstructive Sleep Apnea (OSA) is associated with increased AD risk. We hypothesize that OSA is associated with higher levels of AD biomarkers. The study aims to conduct a systematic review and meta-analysis of the association between OSA and levels of blood and cerebrospinal fluid biomarkers of AD. Two authors independently searched PubMed, Embase, and Cochrane Library for studies comparing blood and cerebrospinal fluid levels of dementia biomarkers between patients with OSA and healthy controls. Meta-analyses of the standardized mean difference were conducted using random-effects models. From 18 studies with 2804 patients, meta-analysis found that cerebrospinal fluid amyloid beta-40 (SMD:-1.13, 95%CI:-1.65 to -0.60), blood total amyloid beta (SMD:0.68, 95%CI: 0.40 to 0.96), blood amyloid beta-40 (SMD:0.60, 95%CI: 0.35 to 0.85), blood amyloid beta-42 (SMD:0.80, 95%CI: 0.38 to 1.23) and blood total-tau (SMD: 0.664, 95% CI: 0.257 to 1.072, I2 = 82, p<0.01, 7 studies) were significantly higher in OSA patients compared with healthy controls. These findings suggest that OSA is associated with an elevation of some biomarkers of AD.
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Affiliation(s)
- Brian Sheng Yep Yeo
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Jin Hean Koh
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Adele Chin Wei Ng
- Department of Otorhinolaryngology-Head and Neck Surgery, Singapore General Hospital, Singapore
| | - Shaun Loh
- Department of Otorhinolaryngology-Head and Neck Surgery, Singapore General Hospital, Singapore; SingHealth Duke-NUS Sleep Centre, Singapore
| | - Anna See
- Department of Otorhinolaryngology-Head and Neck Surgery, Singapore General Hospital, Singapore; SingHealth Duke-NUS Sleep Centre, Singapore
| | - Dennis Chuen Chai Seow
- Department of Geriatric Medicine, Singapore General Hospital, Singapore; SingHealth Duke-NUS Centre of Memory and Cognitive Disorders, Singapore
| | - Song Tar Toh
- Department of Otorhinolaryngology-Head and Neck Surgery, Singapore General Hospital, Singapore; SingHealth Duke-NUS Sleep Centre, Singapore.
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Yeo BSY, Koh JH, Tan BKJ, Ding Y, Teo YH, Alkan U, See A, Loh S, Toh ST. Improved Inflammatory and Cardiometabolic Profile After Soft-Tissue Sleep Surgery for Obstructive Sleep Apnea: A Systematic Review and Meta-analysis. JAMA Otolaryngol Head Neck Surg 2022; 148:862-869. [PMID: 35951318 PMCID: PMC9372898 DOI: 10.1001/jamaoto.2022.2285] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [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: 03/23/2022] [Accepted: 06/23/2022] [Indexed: 11/14/2022]
Abstract
Importance Obstructive sleep apnea (OSA) is associated with a rise in serum inflammatory markers, which may be attenuated by sleep surgery. Objective To evaluate whether sleep surgery was associated with improved levels of proinflammatory markers in adults with OSA. Data Sources Two authors independently searched Cochrane, Embase, and PubMed databases from inception through June 14, 2022. Study Selection Two authors searched the Cochrane, Embase, and PubMed databases for studies comparing preoperative and postoperative levels of serum biomarkers in patients undergoing sleep surgery. Data Extraction and Synthesis Data were extracted from included articles into a structured proforma. Meta-analyses of the standardized mean difference (SMD) were conducted in random-effects models. To ensure relevance to clinicians and patients, the probability of benefit and number needed to treat were calculated for outcomes that demonstrated a statistically significant effect after sleep surgery. Main Outcomes and Measures The primary outcome was the preoperative and postoperative levels of serum biomarkers in patients undergoing sleep surgery, including C-reactive protein (CRP), glucose, low-density lipoprotein (LDL), high-density lipoprotein (HDL), and interleukin-6 (IL-6). Data analysis was performed from April to May 2022. Results Of the 3218 studies screened, 26 studies with 1187 patients (mean [SD] age, 42.8 [11.1] years; 932 [78.5%] men and 255 [21.5%] women) were included. Soft-tissue sleep surgery was associated with a large decrease in CRP (SMD, -0.377; 95% CI, -0.617 to -0.137), total cholesterol (SMD, -0.267; 95% CI, -0.417 to -0.116), LDL (SMD, -0.201; 95% CI, -0.344 to -0.058), IL-6 (SMD, -1.086; 95% CI, -1.952 to -0.221), tumor necrosis factor-α (SMD, -0.822; 95% CI, -1.617 to -0.027), triglyceride (SMD, -0.186; 95% CI, -0.301 to -0.071), and leptin (SMD, -0.519; 95% CI, -0.954 to -0.083) in patients with OSA. Meta-regression highlighted that increased age, higher preoperative score for cumulative sleep time percentage with oxyhemoglobin saturation less than 90% (CT90), and greater change in CT90 postoperatively were associated with a greater decrease in serum CRP levels after soft-tissue sleep surgery. A greater reduction in apnea hypopnea index (AHI) was strongly associated with a greater reduction in total cholesterol and LDL. A greater reduction in body mass index and AHI were also associated with a greater increase in HDL. Conclusions and Relevance The findings of this systematic review and meta-analysis of 26 studies suggest that sleep surgery is associated with decreased levels of CRP, total cholesterol, LDL, triglyceride, IL-6, leptin, and TNF-α, which may improve the inflammatory and cardiometabolic profile of patients who undergo sleep surgery.
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Affiliation(s)
- Brian Sheng Yep Yeo
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Jin Hean Koh
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | | | - Yichen Ding
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Yao Hao Teo
- Yong Loo Lin School of Medicine, National University of Singapore, Singapore
| | - Uri Alkan
- Department of Otorhinolaryngology−Head and Neck Surgery, Rabin Medical Center, Petah Tikva, Israel
- Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel
| | - Anna See
- Department of Otorhinolaryngology−Head and Neck Surgery, Singapore General Hospital, Singapore
- SingHealth Duke University−National University of Singapore Sleep Centre, Singapore
| | - Shaun Loh
- Department of Otorhinolaryngology−Head and Neck Surgery, Singapore General Hospital, Singapore
- SingHealth Duke University−National University of Singapore Sleep Centre, Singapore
| | - Song Tar Toh
- Department of Otorhinolaryngology−Head and Neck Surgery, Singapore General Hospital, Singapore
- SingHealth Duke University−National University of Singapore Sleep Centre, Singapore
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Mendenhall C, Loh S, Chen S, Goettl C, Hirsch K, Wood D. Abstract No. 383 Distribution of parasitized vessels in placenta accreta spectrum. J Vasc Interv Radiol 2020. [DOI: 10.1016/j.jvir.2019.12.444] [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: 11/26/2022] Open
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Loh S, Lin C, Wang P, Lau H. Long term outcome and cephalometric analysis of maxillomandibular rotational advancement surgery for treatment of obstructive sleep apnoea in asian patients. Sleep Med 2019. [DOI: 10.1016/j.sleep.2019.11.645] [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: 11/29/2022]
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Leong S, Farzanegan F, Rajan S, Liu CM, Freed R, Loh S, Rana R, Wang D, Bolanos F, Wang S, Morshedi M, Min J. COMPLEX INFERIOR VENA CAVA FILTER RETRIEVALS: PREDICTORS OF COMPLICATIONS AND FAILURES IN A LARGE, US HEALTHCARE SYSTEM MULTICENTER REFERRAL PROGRAM. Chest 2019. [DOI: 10.1016/j.chest.2019.08.104] [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: 11/25/2022] Open
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Abstract
A holistic approach is pertinent in managing obstructive sleep apnea (OSA). It goes beyond integrated multidisciplinary assessment and management in the hospital setting. Although clinicians should be aware of different treatment modalities and adjunctive measures, proactive management of OSA is as important. The future of OSA management lies in identifying patients at risk of developing OSA and developing strategy to prevent OSA from taking root. It involves active screening of patients with OSA and treating them and identifying patients with OSA with high risk of preventable serious morbidity and death and intervening early to prevent these from happening.
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Affiliation(s)
- Song Tar Toh
- Department of Otolaryngology, Singapore General Hospital, 20 College Road, Singapore 169856, Singapore.
| | - Chu Qin Phua
- Department of Otolaryngology, Sengkang General Hospital, 110 Sengkang East Way, Singapore 544886, Singapore
| | - Shaun Loh
- Department of Otolaryngology, Singapore General Hospital, 20 College Road, Singapore 169856, Singapore
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Lew B, Choi J, Loh S, Sim W. 844 Histpathologic features of alopecia areata. J Invest Dermatol 2017. [DOI: 10.1016/j.jid.2017.02.870] [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: 11/30/2022]
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Rangabashyam M, Huang W, Hao Y, Han HJ, Loh S, Toh ST. State of the art transoral robotic surgery for obstructive sleep apnea-hypopnea syndrome. Robot Surg 2016; 3:13-28. [PMID: 30697552 PMCID: PMC6193426 DOI: 10.2147/rsrr.s95607] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Objective To review the existing literature on the role of transoral robotic surgery (TORS) for tongue base reduction in the management of adult obstructive sleep apnea-hypopnea syndrome (OSAHS). Methods We searched PubMed, MEDLINE, and Scopus databases from the first literature report of this surgical technique to July 30, 2015 for studies investigating the use of TORS for tongue base reduction in treating adult OSAHS. Our primary outcome measures were Apnea– Hypopnea Index (AHI), lowest oxygen saturation (LSAT), Epworth Sleepiness Score (ESS), and the rates of surgical cure (AHI<5) and success (50% reduction in AHI accompanied by a postoperative AHI<20). Our secondary outcome measures were the volume of tissue resected and correlation to AHI, polysomnographic parameters, subjective outcomes, and body mass index. Complications of surgery were also analyzed. Results Thirteen articles were critically evaluated for this research. However, only four case series qualified for statistical analysis of postoperative polysomnographic outcomes and six case series for analysis of postoperative complications. They were case series with a total of 451 adult patients. Pooled analysis revealed statistically significant improvements in AHI, LSAT, and ESS after surgery by 26.83/hour, 5.28% and −8.03, respectively. The average rates of surgical cure and success were 23.8% and 66.7%, respectively. No study reported any deaths or complications related to the use of robotic equipment. The major complication rate was 6.9%, and the minor complication rate was 30.0%. Major complications included major bleeding (2.9%), severe odynophagia with dehydration (3.3%), and oropharyngeal stenosis (0.7%). Minor complications included transient bleeding (0.5%), transient dysphagia (3.8%), and dysgeusia (6.6%). Conclusion TORS for tongue base reduction, as a component of multilevel surgery, is an effective treatment option for OSAHS with an acceptable morbidity. This conclusion is based on the analysis of the results of multiple case series. Future studies should entail prospective randomized controlled trials with larger sample size for longer follow-up period.
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Affiliation(s)
| | - Wenjie Huang
- Yong Loo Lin School of Medicine, National University of Singapore,
| | - Ying Hao
- Health Services Research and Biostatistics Unit, Singapore General Hospital
| | - Hong Juan Han
- Sleep Apnea Surgery Service, Department of Otolaryngology, Singapore General Hospital, .,Sleep Disorders Unit, Singapore General Hospital, .,Duke-NUS Graduate School of Medicine, Singapore,
| | - Shaun Loh
- Sleep Apnea Surgery Service, Department of Otolaryngology, Singapore General Hospital,
| | - Song Tar Toh
- Sleep Apnea Surgery Service, Department of Otolaryngology, Singapore General Hospital, .,Yong Loo Lin School of Medicine, National University of Singapore, .,Sleep Disorders Unit, Singapore General Hospital, .,Duke-NUS Graduate School of Medicine, Singapore,
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Loh S, Suh D, Lew B, Sim W. 668 Role of T-helper 17 cells and T regulatory cells in alopecia areata: Comparison of lesional and serum cytokines between controls and patients. J Invest Dermatol 2016. [DOI: 10.1016/j.jid.2016.02.710] [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: 11/30/2022]
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Mortensen C, De Korompay N, Hersey N, Loh S, Chung J, Liu D, Ho S, Klass D. Transradial approach for uterine artery embolization: too many shades of grey? J Vasc Interv Radiol 2016. [DOI: 10.1016/j.jvir.2015.12.521] [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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Hagiwara E, Loh S. Transjugular approach for upper extremity AV dialysis access interventions. J Vasc Interv Radiol 2016. [DOI: 10.1016/j.jvir.2015.12.578] [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: 11/17/2022] Open
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Gavalas MV, Gasparis AP, Tassiopoulos AK, Loh S, Labropoulos N. Long-term follow-up for percutaneous transluminal angioplasty in renal artery fibromuscular dysplasia. INT ANGIOL 2015; 34:529-537. [PMID: 24824840] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
AIM Percutaneous transluminal angioplasty (PTA) is an effective treatment for renal artery stenosis secondary to fibromuscular dysplasia (FMD). This study aimed to evaluate the short-and long-term outcomes of percutaneous transluminal angioplasty in patients with hypertension and renal artery fibromuscular dysplasia (FMD). Additionally, we sought to identify specific patient factors that may affect outcomes. METHODS This study prospectively enrolled 29 patients with uncontrolled hypertension and renal artery FMD diagnosed by duplex ultrasound and angiography. All patients underwent PTA with the goal of cure or improvement of hypertension. Follow-up was at one-month, 6 months, 12 months and then yearly with minimum follow-up of 2 years and maximum of 5 years. RESULTS Technical success from the intervention was 100%. 21 patients were included in the final analysis. Short-term outcomes: One month after PTA mean systolic blood pressure (138.1 mmHg), diastolic blood pressure (78.6 mmHg), and number of anti-hypertensive medications (1.4) were significantly reduced. Blood pressure improvement was driven by 14/21 (67%) patients who had significant improvement in blood pressure, while 7/21 (33%) did not. These two groups (improved vs. not improved) differed significantly in mean age at intervention (40.6 vs. 58.3 years), duration of hypertension (3.1 vs. 15.4 years), systolic blood pressure (150.4 mmHg vs. 162.1 mmHg), diastolic blood pressure (86.4 mmHg vs. 95.7 mmHg), number of anti-hypertensive medications (2.2 vs. 3.0), serum creatinine (0.82 vs. 1.45), and renal resistive index (0.59 vs. 0.74) prior to intervention. Long-term outcomes: Mean follow-up was 3.86 years. Improvements in blood pressure and anti-hypertensive medications remained significant at five-year follow-up. CONCLUSION PTA is effective at reducing blood pressure in patients with renal artery FMD. Age at intervention, duration of hypertension, and renal function may be used to predict outcomes prior to intervention.
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Abstract
Objective Malignant otitis externa (MOE) is a severe disease with varying outcomes. Despite advances in antibiotic treatment, a significant proportion still succumbs to this disease. We aimed to analyze the effect of clinical factors on prognosis and to review treatment outcomes in our institution. Study Design Case series with retrospective chart review of MOE cases from 2006 to 2011. Setting Department of Otolaryngology–Head and Neck Surgery, National University Hospital, Singapore, a tertiary referral center. Subjects and Methods Patients with MOE admitted for treatment were studied and divided into 2 outcome groups depending on response to a 6-week course of intravenous antibiotics. Demographic and disease factors were analyzed with regard to outcome. Results Nineteen cases were analyzed. Disease resolved in 63.2% after 6 weeks of antibiotics. Mortality was 21.1%. Age, diabetic control, duration of diagnostic delay, cranial nerve involvement, and inflammatory markers were not found to predict prognosis. Erythrocyte sedimentation rate and C-reactive protein levels correlated with disease activity and can be used to monitor progress. Clival involvement was associated with persistent disease ( P = .002). Only 63.2% of cases had positive cultures. Pseudomonas aeruginosa was the main organism, and 33.3% of isolates were multidrug resistant. Outcome was not different in cases where culture-directed therapy was employed vs those where empirical ceftazidime and fluoroquinolone were used ( P = .650). Conclusion Malignant otitis externa remains an insidious disease with significant mortality. Involvement of the clivus portends a poorer prognosis. Combination therapy with intravenous ceftazidime and oral fluoroquinolone remains relevant despite concerns of culture-negative cases and multidrug-resistant Pseudomonas.
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Affiliation(s)
- Shaun Loh
- Otolaryngology–Head and Neck Surgery (ENT), National University Hospital, Singapore
| | - Woei Shyang Loh
- Otolaryngology–Head and Neck Surgery (ENT), National University Hospital, Singapore
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Monsky WL, Molloy C, Jin B, Nolan T, Fernando D, Loh S, Li CS. Quality-of-life assessment after palliative interventions to manage malignant ureteral obstruction. Cardiovasc Intervent Radiol 2013; 36:1355-63. [PMID: 23404519 DOI: 10.1007/s00270-013-0571-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 01/12/2013] [Indexed: 12/15/2022]
Abstract
PURPOSE Malignancies may cause urinary tract obstruction, which is often relieved with placement of a percutaneous nephrostomy tube, an internal double J nephro-ureteric stent (double J), or an internal external nephroureteral stent (NUS). We evaluated the affect of these palliative interventions on quality of life (QoL) using previously validated surveys. METHODS Forty-six patients with malignancy related ureteral obstruction received nephrostomy tubes (n = 16), double J stents (n = 15), or NUS (n = 15) as determined by a multidisciplinary team. QoL surveys were administered at 7, 30, and 90 days after the palliative procedure to evaluate symptoms and physical, social, functional, and emotional well-being. Number of related procedures, fluoroscopy time, and complications were documented. Kruskal-Wallis and Friedman's test were used to compare patients at 7, 30, and 90 days. Spearman's rank correlation coefficient was used to assess correlations between clinical outcomes/symptoms and QoL. RESULTS Responses to QoL surveys were not significantly different for patients receiving nephrostomies, double J stents, or NUS at 7, 30, or 90 days. At 30 and 90 days there were significantly higher reported urinary symptoms and pain in those receiving double J stents compared with nephrostomies (P = 0.0035 and P = 0.0189, respectively). Significantly greater fluoroscopy time was needed for double J stent-related procedures (P = 0.0054). Nephrostomy tubes were associated with more frequent minor complications requiring additional changes. CONCLUSION QoL was not significantly different. However, a greater incidence of pain in those receiving double J stents and more frequent tube changes in those with nephrostomy tubes should be considered when choosing palliative approaches.
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Affiliation(s)
- Wayne Laurence Monsky
- Department of Radiology, University of Washington Medical Center, 1959 Pacific Ave NE, Box 357115, Seattle, WA, 98195, USA,
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Abstract
Intussusception is the telescoping of proximal bowel wall into the lumen of a distal segment. Whilst it is common in children, intussusception in adults is rare, and predominantly occurs secondary to an underlying malignant neoplasm. Abdominal and pelvic computed tomography (CT) is preferred for detection of lead points and lesion localisation. We present the case of a 79-year-old female with a four-day history of colicky abdominal pain followed by obstipation and distension. CT demonstrated a rounded heterogeneous density protruding into the upper rectal lumen, and also left-sided colonic obstruction. Emergency laparotomy revealed a mid-sigmoid colonic mass intussuscepting into the rectum. Histopathology confirmed a T3N1 moderately differentiated colonic adenocarcinoma. Given the high likelihood of underlying malignancy, surgical reduction of the intussusceptum may be complicated by perforation and tumour spillage. En bloc resection using oncologic surgical principles remains the first line treatment.
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Affiliation(s)
| | - S Loh
- University of Melbourne, Melbourne, Australia
| | - P Smart
- University of Melbourne, Melbourne, Australia
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Samuelson S, Hofmann L, Kothary N, Loh S, Louie J, Kuo W, Hovsepian D, Sze D, Hwang G. Abstract No. 315: Design and implementation of IR-specific features in an electronic medical records system. J Vasc Interv Radiol 2012. [DOI: 10.1016/j.jvir.2011.12.371] [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: 10/28/2022] Open
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Samuelson S, Jackson B, Hubeny C, Wong A, Loh S, Wang D, Shah R, Kothary N, Louie J, Sze D, Hofmann L, Hovsepian D, Kuo W, Hwang G. Abstract No. 375: Cancer chemotherapeutics and anti-cancer drugs: a primer for interventional radiologists. J Vasc Interv Radiol 2012. [DOI: 10.1016/j.jvir.2011.12.494] [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: 10/28/2022] Open
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McGahan JP, Loh S, Boschini FJ, Paoli EE, Brock JM, Monsky WL, Li CS. Maximizing parameters for tissue ablation by using an internally cooled electrode. Radiology 2010; 256:397-405. [PMID: 20530754 DOI: 10.1148/radiol.09090662] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To compare an algorithm of gradually ramped-up power to a full-power-level technique to determine which technical parameters maximized tissue coagulation by using a saline-perfused electrode. MATERIALS AND METHODS Institutional review board approval was not necessary and animal committee approval was unnecessary because an ex vivo bovine liver model was used and the animals were not specifically killed for this study. This four-part experiment utilized multiple ablations of ex vivo bovine liver with a standard radiofrequency (RF) generator and an internally cooled needle. First, 10 RF ablations were performed at 20-60 W for 12 minutes. Second, ablation volumes obtained from an algorithm of eight ablations performed at 50 W were compared with those obtained from an algorithm of eight ablations that were gradually ramped-up to 50 W, until full impedance. Third, volumes obtained from 10 ablations performed at impedance control power levels were compared with those obtained from 10 ablations performed with a gradual ramp-up of power that started at 50 W, terminating at full impedance. Last, the third part was repeated, but with 11 ablations continuing past full impedance for 12 minutes each. RESULTS In the first part, maximum measurements of tissue coagulation seemed to plateau from 40 to 60 W. The second part produced significantly larger measurements of tissue coagulation than did the use of a constant power level of 50 W. The third and final parts produced larger measurements of tissue coagulation than did utilizing full power for 12 minutes. Larger measurements and volumes were obtained from repeat ablations after the generator reached impedance level than were obtained from ablations stopped at maximum impedance. CONCLUSION A gradual ramp-up of power and repeating ablations after power impedance level is reached are the two methods that increased tissue ablation in this ex vivo experiment.
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Affiliation(s)
- John P McGahan
- Department of Radiology, University of California, Davis Medical Center, 4860 Y St, Suite 3100, Sacramento, CA 95817, USA.
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Loh S, Bagheri S, Katzberg RW, Fung MA, Li CS. Delayed adverse reaction to contrast-enhanced CT: a prospective single-center study comparison to control group without enhancement. Radiology 2010; 255:764-71. [PMID: 20406882 DOI: 10.1148/radiol.10091848] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
PURPOSE To prospectively assess the incidence of delayed adverse reactions (DARs) in patients undergoing contrast material-enhanced computed tomography (CT) with the low osmolar nonionic contrast agent iohexol and compare with the incidence of DARs in patients undergoing unenhanced CT as control subjects. MATERIALS AND METHODS Institutional review board approval and informed written consent for this prospective study were obtained. The study was HIPAA compliant. Patients undergoing CT for routine indications were enrolled from a random next-available scheduling template by an on-site clinical trials monitor. All subjects received a questionnaire asking them to indicate any DAR occurring later than 1 hour after their examination. Sixteen manifestations were listed and included rash, skin redness, skin swelling, nausea, vomiting, and dizziness, among others. To ensure maximal surveillance, a clinical trials coordinator initiated direct telephone contact for further assessment. Patients suspected of having moderately severe cutaneous reactions were invited to return for a complete dermatologic clinical assessment including skin biopsy, if indicated. Statistical analysis was performed by using a two-sided Wilcoxon-Mann-Whitney test, a logistic regression utilizing a chi(2) test to adjust for sex and age, and a two-sided Fisher exact test. RESULTS A total of 539 patients (258 receiving iohexol and 281 not receiving contrast material) were enrolled. DARs were observed in 37 (14.3%) of 258 subjects receiving iohexol and in seven (2.5%) of 281 subjects in the control group (P < .0001, chi(2) test) after adjusting for sex and age. Specific manifestations of DARs that were significantly more frequent at contrast-enhanced CT were skin rash (P = .0311), skin redness (P = .0055), skin swelling (P = .0117), and headache (P = .0246). DARs involving the skin included generalized rashes of the face, neck, chest, back, and extremities and were often associated with swelling, erythema, and pruritus. CONCLUSION This study substantiates a frequent occurrence of DARs at contrast-enhanced CT compared with that in control subjects. Continued growth in the use of contrast-enhanced CT suggests a need for greater awareness and attention to prevention and management.
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Affiliation(s)
- Shaun Loh
- Department of Diagnostic Radiology, University of California, Davis Medical Center, 4860 Y St, Suite 3100, Sacramento, CA 95817, USA.
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Monsky WL, Garza AS, Loh S, Link DP. Snare Technique for the Placement of a Peripherally Inserted Central Catheter in the Neonatal and Pediatric Patient. J Vasc Access 2010; 11:100-5. [DOI: 10.1177/112972981001100203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Purpose The placement of a peripherally inserted central catheter (PICC) for neonatal or pediatric patients may at times be technically challenging. We describe an alternate method of placing a PICC in neonatal and pediatric patients with difficult venous access. Methods An Amplatz gooseneck snare is advanced from the femoral vein to the basilic vein, as a target for puncture and guidewire positioning, allowing PIcc placement. Between 1999 and 2006, 44 PICCs were placed in the manner described. The medical records were reviewed allowing for up to 7 yrs of patient follow-up. Results Ninety-five percent of PICCs were successfully placed using the snare technique. Two placements were aborted and two procedural complications occurred. The review revealed no evidence of osteomyelitis, nerve injury, deep venous thrombosis or leg length discrepancy. Conclusion this technique offers an alternate method for PICC placement in neonatal and pediatric patients when conventional methods are unsuccessful. The technique avoids the need for intermediate to long-term jugular, subclavian or femoral vein access.
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Affiliation(s)
- Wayne L. Monsky
- Department of Radiology, University of California, Davis Medical Center, Sacramento, CA - USA
| | - Armando S. Garza
- University of California, School of Medicine, University of California, Davis Medical Center, Sacramento, CA - USA
| | - Shaun Loh
- Department of Radiology, University of California, Davis Medical Center, Sacramento, CA - USA
| | - Daniel P. Link
- Department of Radiology, University of California, Davis Medical Center, Sacramento, CA - USA
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Katzberg R, Loh S, Bagheri S, Fung M, Li CS. CMR2009: 6.01: Prospective clinical assessment of delayed reactions resulting from contrast-enhanced CT. Contrast Media Mol Imaging 2009. [DOI: 10.1002/cmmi.329] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Monsky W, Badawi R, Kim I, Loh S, Dong P, Deutsch L. Abstract No. 183: Semi-Automated Segmentation for Volumetric Analysis of Intra-Tumoral Ethiodol Uptake and Response Following Chemoembolization of Hepatocellular Carcinoma. J Vasc Interv Radiol 2009. [DOI: 10.1016/j.jvir.2008.12.172] [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: 12/01/2022] Open
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Abstract
In this study, the costs and cost savings associated with departmentwide implementation of a picture archiving and communication system (PACS) as compared to the projected budget at the time of inception were evaluated. An average of $214,460 was saved each year with a total savings of $1,072,300 from 1999 to 2003, which is significantly less than the $2,943,750 projected savings. This discrepancy can be attributed to four different factors: (1) overexpenditures, (2) insufficient cost savings, (3) unanticipated costs, and (4) project management issues. Although the implementation of PACS leads to cost savings, actual savings will be much lower than expected unless extraordinary care is taken when devising the budget.
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Affiliation(s)
- Arra Suresh Reddy
- Department of Radiology, Beth Israel Deaconess Medical Center/Harvard Medical School, One Deaconess Rd, Room 327C, Boston, MA 02215 USA
| | - Shaun Loh
- Department of Radiology, Beth Israel Deaconess Medical Center/Harvard Medical School, One Deaconess Rd, Room 327C, Boston, MA 02215 USA
| | - Robert A. Kane
- Department of Radiology, Beth Israel Deaconess Medical Center/Harvard Medical School, One Deaconess Rd, Room 327C, Boston, MA 02215 USA
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Reddy AS, Lang EV, Cutts J, Loh S, Rosen MP. Fibrin sheath removal from central venous catheters: an internal snare manoeuvre. Nephrol Dial Transplant 2007; 22:1762-5. [PMID: 17403697 DOI: 10.1093/ndt/gfm154] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.9] [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: 11/14/2022] Open
Abstract
BACKGROUND Dysfunction of haemodialysis catheters is most commonly due to a narrowing of the catheter lumen and/or formation of a fibrin sheath around the catheter tip. Reported methods for restoring patency of the catheter lumen include passage of a J-tipped guide wire, passage of a biopsy brush through the catheter, or infusion of a thrombolytic agent into the catheter. While these methods are often effective, they suffer from several limitations. We present a minimally invasive technique to remove thrombi and debris from within the lumen of a partially thrombosed haemodialysis catheter while simultaneously stripping the fibrous sheath. METHODS A 0.089 cm nitinol wire is bent to create a loop, which is then inserted via the catheters. Upon exiting the lumen of the catheters, the nitinol wire forces a snare open, which disrupts the fibrin sheath and catches intraluminal thrombi and debris. The technique requires no anaesthesia or recovery time. RESULTS Initial clinical success in our series was achieved in all patients (7/7) as evidenced by restoration of target flow rates on subsequent haemodialysis. None of the patients experienced any complications as a result of the procedure. The catheter 2-, 4-, and 6-week primary success rates were 100% (8/8), 100% (8/8), and 100% (8/8) respectively with a mean duration of 17.1 weeks (range 8-40 weeks). CONCLUSIONS The internal snare technique is an effective, inexpensive and minimally invasive approach to restoring patency to failed central venous access catheters.
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Affiliation(s)
- Arra S Reddy
- Beth Israel Deaconess Medical Center, One Deaconess Road, Room 327C, Boston, MA 02215, USA
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Zhou J, Pan M, Loh S, Xie Z, Lim Y, Lilly M, Glaser K, Albert D, Davidsen S, Chen CS. ABT-869, a novel multi-target receptor tyrosine kinase inhibitor (RTKI), combined with chemotherapy is synergistic in the therapy of acute myeloid leukemia cells with FLT3-ITD mutation (FLT3-AML). J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.13064] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
13064 Background: Internal tandem duplications (ITDs) of fms-like tyrosine kinase 3 (FLT3) receptor are identified in 20–25% of adult AML patients associated with poor prognosis. ABT-869 is active in FLT3-AML and is currently under clinical investigaton. We hypothesize that the combination of ABT-869 with chemotherapy can improve the therapeutic index in FLT3-AML. Methods: Using Calcusyn software, the additive, synergistic or antagonistic effect of ABT-869 with concurrent or sequential cytosine arabinoside (Ara-C) or doxorubicin (Dox) was measured in MV4–11 and MOLM-14 cells. The synergistic combination sequence was further tested in a MV4–11 xenograft model in four groups (10 mice/group) including control, Ara-C, ABT-869, and combination (Ara-C first for 4 days, then daily ABT-869). Cell cycle analysis and apoptosis and signal pathway assays were performed in vitro and in vivo. Results: ABT-869 induced dose- and time-dependent apoptosis on FLT3-AML cells resulting in down regulation of p-FLT3, p-STAT5, Bcl-XL and up regulation of p53 and BID. ABT-869 caused G1-phase arrest and the removal of cells in the S- and G2/M-phase mediated by reduction of cyclins D and E. We observed significant synergistic effect with Ara-C or Dox first, followed by ABT-869, as well as in concurrent treatment with ABT-869 and Dox. Simultaneous treatment with ABT-869 and Ara-C only achieved additive effect. Conversely, we found an antagonistic effect in the sequence of pretreatment of ABT-869 followed by chemotherapy. In a MV4–11 xenograft model, all mice succumbed to leukemia in the control and Ara-C groups (median survival = 53 and 55.5 days respectively). Combination therapy gave a faster reduction of tumor volume compared to ABT-869 treatment alone (p=0.03) without recurrence of leukemia in either group by day 67. In vivo immunohistochemistry (IHC) analysis revealed ABT-869 potently inhibited VEGF and phosphor-ERK. Conclusions: ABT-869 can be given after Ara-C or Dox to act synergistically. Our study suggests that combinations of RTKIs with chemotherapy should be carefully tested prior to clinical protocol development. A clinical trial of such combination therapy in FLT3-AML is warranted. No significant financial relationships to disclose.
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Affiliation(s)
- J. Zhou
- National University of Singapore, Singapore, Singapore; National University Hospital, Singapore, Singapore; Oncology Research Institute, National University of Sinapore, Singapore; Loma Linda University School of Medicine, Loma Linda, CA; Abbott Laboratories, Chicago, IL
| | - M. Pan
- National University of Singapore, Singapore, Singapore; National University Hospital, Singapore, Singapore; Oncology Research Institute, National University of Sinapore, Singapore; Loma Linda University School of Medicine, Loma Linda, CA; Abbott Laboratories, Chicago, IL
| | - S. Loh
- National University of Singapore, Singapore, Singapore; National University Hospital, Singapore, Singapore; Oncology Research Institute, National University of Sinapore, Singapore; Loma Linda University School of Medicine, Loma Linda, CA; Abbott Laboratories, Chicago, IL
| | - Z. Xie
- National University of Singapore, Singapore, Singapore; National University Hospital, Singapore, Singapore; Oncology Research Institute, National University of Sinapore, Singapore; Loma Linda University School of Medicine, Loma Linda, CA; Abbott Laboratories, Chicago, IL
| | - Y. Lim
- National University of Singapore, Singapore, Singapore; National University Hospital, Singapore, Singapore; Oncology Research Institute, National University of Sinapore, Singapore; Loma Linda University School of Medicine, Loma Linda, CA; Abbott Laboratories, Chicago, IL
| | - M. Lilly
- National University of Singapore, Singapore, Singapore; National University Hospital, Singapore, Singapore; Oncology Research Institute, National University of Sinapore, Singapore; Loma Linda University School of Medicine, Loma Linda, CA; Abbott Laboratories, Chicago, IL
| | - K. Glaser
- National University of Singapore, Singapore, Singapore; National University Hospital, Singapore, Singapore; Oncology Research Institute, National University of Sinapore, Singapore; Loma Linda University School of Medicine, Loma Linda, CA; Abbott Laboratories, Chicago, IL
| | - D. Albert
- National University of Singapore, Singapore, Singapore; National University Hospital, Singapore, Singapore; Oncology Research Institute, National University of Sinapore, Singapore; Loma Linda University School of Medicine, Loma Linda, CA; Abbott Laboratories, Chicago, IL
| | - S. Davidsen
- National University of Singapore, Singapore, Singapore; National University Hospital, Singapore, Singapore; Oncology Research Institute, National University of Sinapore, Singapore; Loma Linda University School of Medicine, Loma Linda, CA; Abbott Laboratories, Chicago, IL
| | - C. S. Chen
- National University of Singapore, Singapore, Singapore; National University Hospital, Singapore, Singapore; Oncology Research Institute, National University of Sinapore, Singapore; Loma Linda University School of Medicine, Loma Linda, CA; Abbott Laboratories, Chicago, IL
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Affiliation(s)
- Shaun Loh
- Departments of Radiology and Neurosurgery, Beth Israel Deaconess Medical Center / Harvard Medical School, and Department of Radiology, Massachusetts General Hospital / Harvard Medical School, Boston, Massachusetts
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Reddy AS, Loh S, Cutts J, Rachlin J, Hirsch JA. New approach to the management of acute disc herniation. Pain Physician 2005; 8:385-90. [PMID: 16850062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
BACKGROUND Over 500,000 percutaneous disc decompression procedures have been performed in the past 20 years. Various percutaneous techniques include chemonucleolysis, percutaneous lumbar discectomy, and laser discectomy which have reported success rates in the 70% to 75% range. This retrospective evaluation of 49 patients who underwent nucleoplasty procedures for treatment of herniated discs, evaluates the effectiveness of nucleoplasty in the reduction of pain, improvement of functional activity, and reduction of pain medication. OBJECTIVE To illustrate the effectiveness of nucleoplasty in reducing low back pain in symptomatic patients with contained herniated discs. STUDY DESIGN A retrospective, non-randomized study. METHODS Forty-nine patients with either axial or radicular low back pain who had undergone the nucleoplasty procedure were included in this analysis. Patients were categorized in one of three different groups depending on time elapsed since the procedure was performed: less than 6 months, between 6 months and 1 year, and greater than 1 year. Pain reduction, work impairment, leisure impairment, medication use and patient satisfaction were all recorded during this study. Pain was quantified using a numeric pain scale from 0 to 10. Work and leisure impairment were measured on a scale of 1 to 5, with 1 signifying no impairment and 5 signifying extreme impairment. Medication use and patient satisfaction were also measured on a scale of 1 to 5. RESULTS Significant pain relief, functional improvement, and a decrease in medication use were achieved following nucleoplasty. There were no complications associated with the procedure. CONCLUSION Nucleoplasty should be used in those patients who fail conservative medical management including medication, physical therapy, behavioral management, psychotherapy, and who are unwilling to undergo a more invasive technique such as spinal surgery.
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Affiliation(s)
- Arra S Reddy
- Interventional Neuroradiology, Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, One Deaconess Rd., Suite 580, Boston, MA 02215, USA.
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Loh S. CT Guided Direct Transoral Approach to C2 for Percutaneous
Vertebroplasty. Pain Physician 2005. [DOI: 10.36076/ppj.2005/8/235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Affiliation(s)
- Shaun Loh
- Departments of Radiology and Neurosurgery and Hospitals, Beth Israel Deaconess Medical Center/Harvard Medical School, Boston, MA
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Reddy AS, Hochman M, Loh S, Rachlin J, Li J, Hirsch JA. CT guided direct transoral approach to C2 for percutaneous vertebroplasty. Pain Physician 2005; 8:235-8. [PMID: 16850077] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
BACKGROUND Percutaneous vertebroplasty is a well-established procedure consisting of the percutaneous injection of a biomaterial, usually Polymethyl methacrylate (PMMA), into a vertebral body. In most cases, this procedure affords significant pain relief and strengthens the bone. Vertebroplasty is most typically performed successfully with patients with acute compression fractures. OBJECTIVE We report a case of percutaneous vertebroplasty via the transoral approach, performed with computed axial tomography (CT) scan guidance. METHODS The procedure was performed in a 74-year-old male with a C2 vertebral body lytic lesion. RESULTS This uncomplicated, minimally invasive procedure relieved the patient's pain. The transoral route is the most direct operative approach to the pathology in the upper cervical spine. CONCLUSION When used with the CT scanner to facilitate accurate placement of the needle, the transoral approach provides a safe and precise operative approach to the upper cervical spine.
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Affiliation(s)
- Arra S Reddy
- Interventional Neuroradiology, Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, One Deaconess Rd, Suite 580, Boston, MA 02215, USA
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Cheng T, Loh S, Tsai G, Chiang G, Chieng G. 1P-0313 Effects of alcohol on the intracellular H+ and transmembrane regulators in the human myocardium. ATHEROSCLEROSIS SUPP 2003. [DOI: 10.1016/s1567-5688(03)90382-5] [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: 11/16/2022]
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Abstract
The objective of this study was to measure the force applied to attach crimpable hooks securely to rectangular stainless steel archwires, both inside and outside the mouth. A specially designed strain gauge was utilized to measure the force applied by each operator. In vitro testing of the attached hooks was carried out using an Instron Universal Testing Machine. Two operators crimped a total of 80 TP Orthodontic crimpable hooks to 0.019 x 0.025-inch stainless steel archwires. For one operator there was a significant difference between the intra- and extra-oral forces used to produce firmly attached crimpable hooks (P = 0.03). However, in vitro testing demonstrated no statistically significant difference between the force levels required to displace the crimped hooks for either operator. The clinical significance of these findings is also discussed. Better reliability of crimpable hooks may be achieved by placing them out of the mouth.
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Affiliation(s)
- A Johal
- Department of Orthodontics, 3rd Floor, Dental School, Turner Road, London E1 1BB, UK
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Loh S, Heng JK, Ward-Booth P, Winchester L, McDonald F. A radiographic analysis of computer prediction in conjunction with orthognathic surgery. Int J Oral Maxillofac Surg 2001; 30:259-63. [PMID: 11518345 DOI: 10.1054/ijom.2001.0089] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.1] [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]
Abstract
This retrospective study analysed the accuracy and reliability of predictions generated in patients treated with orthognathic surgery by comparing Quick Ceph Image software (Quick Ceph Image Pro version 3.0) predictions with post-surgical lateral cephalographs. Pre- and post-surgical lateral cephalographs of 28 adult patients (12 males and 16 females) were scanned into the computer and 28 landmarks were identified and digitized. Digitization error was assessed from repeated digitization. Fourteen measurements of the predicted and actual postsurgical hard tissue landmarks were compared using Student's t-test. Results showed a good correlation between repeated digitization for all measurements. Student's t-test indicated that 10 of the 14 measurements showed no statistically significant differences. Only the ANB (P=0.008), FMA (P=0.001), SN-Mxl (P=0.03) and Wit's (P=0.0001) showed statistically significant differences between the predicted and actual measurements. However only the Wit's showed clinical significant differences between the two measurements. Caution still must remain as the surgeon may not achieve his planned position in an individual patient. In some cultures there may also be medico-legal implications of these predictions.
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Affiliation(s)
- S Loh
- Department of Orthodontics and Paediatric Dentistry, Guy's King's and St Thomas' Dental Institute, London, UK
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Mukherjee S, Nelson D, Loh S, van Bruggen I, Palmer LJ, Leong C, Garlepp MJ, Robinson BW. The immune anti-tumor effects of GM-CSF and B7-1 gene transfection are enhanced by surgical debulking of tumor. Cancer Gene Ther 2001; 8:580-8. [PMID: 11571536 DOI: 10.1038/sj.cgt.7700347] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [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: 05/16/2001] [Indexed: 11/09/2022]
Abstract
Malignant mesothelioma (MM) is a solid tumor largely unresponsive to conventional therapies. Immunological gene therapy shows promise in murine models and human clinical trials; however, the role of surgery in combination with gene therapy has not been widely studied. The aim of this study was to determine if debulking surgery improved the effectiveness of gene therapy in a murine MM model. Mice were subcutaneously inoculated with the MM cell line, AC29, at two different sites, 4 days apart, to allow a surgical and distal site tumor to develop. Once tumors were established, the surgical site tumor was debulked and vaccination of syngeneic tumor transfectants encoding genes for IL-4, IL-2, GM-CSF, B7-1 or allogeneic MHC molecules commenced at a site away from both tumors, and tumor growth was measured. Neither debulking surgery nor gene therapy alone delayed tumor growth. However, there was a clear delay of tumor growth when debulking surgery was combined with vaccination of tumor transfectants expressing B7-1 or high levels of GM-CSF. Combinations of these two transfectants did not lead to a synergistic effect. This study demonstrates that debulking surgery can augment the immunostimulatory effects of immunological gene therapy and can delay tumor growth. This has implications for the future design of human gene therapy trials for solid tumors such as MM.
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Affiliation(s)
- S Mukherjee
- Department of Medicine, University of Western Australia, Perth, Australia.
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Loh S, Maznah I. The effect of different milks and milk proteins on the growth of Bifidobacterium infantis ATCC 27920 in vitro. Malays J Nutr 1999; 5:61-70. [PMID: 22692359] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Bifidobacteria is a well known bacteria that is found in abundance in the intestine of infants which provides several health and nutritional benefits. Realizing the many benefits of bifidobacteria to human, this study has been conducted with the objective to determine the growth promotional effect of different types of milk and milk proteins on Bifidobacterium species. One strains of Bifiodobacterium species that is B. infantis was used to study the growth promoting effect of human milk, cow's milk, goat's milk, milk based infant formula, soy-based infant formula, lactoferrin (1 mg/ml), lactoperoxidase (1p~g/ml), lysozyme (1 mg/ml) and the mixture of these three proteins. The growth promotion assay was done using the 96-well culture plates which consists of 200 (1 Trypticase-Peptone-Yeast extract (TPY) medium, 50 4 sample and 10 1il of bacteria inoculum. Control consists of PBS instead of the samples. The assay was incubated anaerobically at 370C for 18 hours before being spread on the agar plate containing TPY medium with agar. Comparison was made between the mean count (log cfu/ml) of different types of milks, between infant formula and between milk proteins. From the results, Oneway ANOVA test at P<0.05 showed that there was significant differences in the mean counts (log cfu/ml) between the milks (P = 0.0000). A similar trend was observed in the mean count (log cfu/mI) between the infant formulas (P = 0.0 124) and also between the milk proteins (P = 0.0005). Duncan Multiple Range tests showed that there was significant differences between all the milks and control and among the milks themselves. There was however, no significant difference among the two types of infant formulas. The milk proteins also showed significant differences between the proteins and control and among themselves except for lysozyme which showed no significant differences with lactoferrin. This study showed that the growth of B. infantis could be promoted by different kinds of milks and milk proteins in vitro. Comparing the differences in growth promoting effect between samples and control indicated that human milk has the highest growth promoting effect followed by cow's milk and the mixture of the three milk prtoeins. Lysozyme showed the lowest in term of differences in percentage of growth promoting effect among all these samples. In conclusion the findings of this study supported that human milk ios the best milk choice for infant in comparison to other types of milk in promoting the growth of bifidobacteria. In additon, this tudy also found that milk protein when used in combination may show better growth promoiotive effect than when used singly.
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Affiliation(s)
- S Loh
- Department of Nutrition and Health Sciences, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor Darul Ehsan
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Leong CC, Marley JV, Loh S, Robinson BW, Garlepp MJ. The induction of immune responses to murine malignant mesothelioma by IL-2 gene transfer. Immunol Cell Biol 1997; 75:356-9. [PMID: 9315477 DOI: 10.1038/icb.1997.55] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [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: 02/05/2023]
Abstract
Stable IL-2 transfectant clones have been derived from two non-immunogenic murine malignant mesothelioma (MM) cell lines to investigate the induction of protective antitumor immunity to MM. AC29-IL-2 transfectant clones grew at a slower rate in vivo than the parental cell line or a transfectant control clone but all inoculated mice developed tumours despite the continued ability of the tumour cells to express IL-2. Tumour development after inoculation of AB1-IL-2 transfectants varied, the degree of in vivo inhibition (40-100%) being directly related to the rate of IL-2 secretion of the transfectants. When mice which had rejected the AB1-IL-2 transfectants were challenged with parental AB1 cells, a proportion (16-70%) of mice from each group remained tumour free at least 45 days after challenge (naive mice developed tumours within 26 days). The inhibition of growth of the initial inoculum of AB1-IL-2 transfectants was independent of CD4+ and CD8+ cells, consistent with the demonstration of non-specific cytotoxic activity by splenocytes from mice inoculated with the IL-2 transfectants. These data suggest that IL-2 expression by MM cells is capable of generating in vivo immunity to the tumour. This immunity may be relatively weak or may be subject to down-regulation so that consistent rejection of unmodified tumour cells is not achieved. Genetic modification with combinations of genes, including IL-2 and B7-1, will be necessary for reliable generation of protective immunity to MM.
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Affiliation(s)
- C C Leong
- Australian Neuromuscular Research Institute, Queen Elizabeth II Medical Center, Nedlands, Australia
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Abstract
Transfection of the genes encoding the co-stimulatory molecules B7-1 and B7-2 has enhanced the development of immunity to a variety of experimental tumors, although most of these were inherently immunogenic. We have determined the effect of expression of these genes on the induction of immunity to 2 non-immunogenic murine malignant mesothelioma (MM) cell lines (AC29 and AB1). We had previously shown that B7-1 transfection into AC29 delayed but did not prevent tumor development by certain of the transfectant clones. Here we demonstrate that over-expression of B7-1 can inhibit tumor development by certain AB1-B7-1 clones, that inhibition of transfectant growth is dependent on CD4+ and CD8+ T cells and that mice that reject some of these transfectant clones are capable of rejecting subsequent inocula of the parental cell line, AB1. The transfectant clones can generate tumor-specific cytotoxic T cells. By contrast, expression of B7-2 in several clones derived from either AB1 or AC29 had no significant effect on the development of tumors in vivo. Our data are consistent with data from other systems that show differences in the effect of modification by B7-1 or B7-2 on the modulation of anti-tumor immune responses. They demonstrate that such modifications can induce protective immunity against an MM cell line but confirm the intra- and inter-tumoral heterogeneity in the effect of genetic modification on the induction of immunity. Our observations are relevant to human MM because these cell lines have been derived from asbestos-induced tumors and share many properties with human cell lines of the same histological type.
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Affiliation(s)
- C C Leong
- Australian Neuromuscular Research Institute, Queen Elizabeth II Medical Centre, Nedlands
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Leong C, Marley J, Loh S, Robinson B, Garlepp M. Induction and maintenance of T-cell response to a nonimmunogenic murine mesothelioma cell line requires expression of B7-1 and the capacity to upregulate class II major histocompatibility complex expression. Cancer Gene Ther 1996; 3:321-30. [PMID: 8894251] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Intratumoral expression of the T-cell costimulator B7-1 has been reported to induce tumor-specific immunity against immunogenic, but not nonimmunogenic, tumors. We transfected the B7-1 gene into a nonimmunogenic murine mesothelioma cell line that constitutively expresses high levels of class I major histocompatibility complex (MHC) and transforming growth factor-beta (TGF-beta). Tumor development by two of the four B7-1 transfectant clones was markedly delayed, although all clones eventually formed tumors. Retardation of tumor growth required both CD4+ and CD8+ T cells. Tumor-specific cytotoxic T-lymphocytes (CTLs) were elicited in response to the least (AC29-B7-6), but not the most (AC29-B7-7), tumorigenic transfectant clone. Tumor-specific CTL activity could be detected at early time points but not at the time of tumor outgrowth. This lack of responsiveness was tumor antigen specific. Differences in immunogenicity of transfectant clones did not relate to the level of expression of MHC class I, vascular cell adhesion molecule-1, or transfected B7-1, or to the level of TGF-beta secreted. Class II MHC expression was most readily inducible in those transfectant clones whose growth in vivo was most delayed. An explant cell line derived from a tumor that developed from AC29-B7-6 had a markedly reduced capacity to upregulate MHC class II expression and produced tumors in vivo at a faster rate than did the parental cell line. Thus, B7-1 expression in this nonimmunogenic tumor cell line can promote the generation of tumor-specific CTLs with consequent retardation of tumor development, and coexpression of MHC class II seems likely to play an important role in this process. This work also illustrates that clonal heterogeneity within a single tumor and the development of immunological nonresponsiveness resulting in tumor outgrowth, even in the presence of continued B7-1 expression, are potential difficulties associated with this therapeutic approach.
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Affiliation(s)
- C Leong
- Australian Neuromuscular Research Institute, Queen Elizabeth II Medical Centre, Nedlands, Australia
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Abstract
Low-barrier or short, strong hydrogen bonds have been proposed to contribute 10 to 20 kilocalories per mole to transition-state stabilization in enzymatic catalysis. The proposal invokes a large increase in hydrogen bond energy when the pKa values of the donor and acceptor (where Ka is the acid constant) become matched in the transition state (delta pKa=0). This hypothesis was tested by investigating the energetics of hydrogen bonds as a function of delta pKa for homologous series of compounds under nonaqueous conditions that are conducive to the formation of low-barrier hydrogen bonds. In all cases, there was a linear correlation between the increase in hydrogen-bond energy and the decrease in delta pKa, as expected from simple electrostatic effects. However, no additional energetic contribution to the hydrogen bond was observed at delta pKa=0. These results and those of other model studies suggest alternative mechanisms by which hydrogen bonds can contribute to enzymatic catalysis, in accord with conventional electrostatic considerations.
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Affiliation(s)
- S O Shan
- Department of Biochemistry, Stanford University, CA 94305-5307,USA
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McKeage MJ, Mistry P, Ward J, Boxall FE, Loh S, O'Neill C, Ellis P, Kelland LR, Morgan SE, Murrer B. A phase I and pharmacology study of an oral platinum complex, JM216: dose-dependent pharmacokinetics with single-dose administration. Cancer Chemother Pharmacol 1995; 36:451-8. [PMID: 7554035 DOI: 10.1007/bf00685793] [Citation(s) in RCA: 68] [Impact Index Per Article: 2.3] [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: 01/25/2023]
Abstract
JM216 [bis-acetato-ammine-dichloro-cyclo-hexylamine-platinum (IV)] is an oral platinum complex with in vivo activity against murine and human tumor models and a lack of nephro- and neurotoxicity in rodents. During a phase I study of a single-dose schedule, JM216 was given in dry-filled hard gelatin capsules by mouth without hydration or diuresis. In all, 37 patients were given a total of 88 courses at doses ranging from 60 to 700 mg/m2. The study was stopped before the MTD was reached because of nonlinear pharmacokinetics. Myelosuppression was manifest by leucopenia or thrombocytopenia and showed marked variability at 420-700 mg/m2. Vomiting was mild and controllable by antiemetics in approximately 50% of courses. The onset of vomiting was delayed to 4 h after during ingestion. There was no nephro-, oto- or neuro-toxicity. A partial response was recorded in a patient with recurrent ovarian cancer, and significant falls in plasma tumour markers (CA125) were seen in two further cases. Plasma pharmacokinetics were linear and showed moderate interpatient variability at dose levels of < or = 120 mg/m2. At dose levels of > or = 200 mg/m2, Cmax and AUC increased less than proportionally to dose. This was associated with greater interpatient pharmacokinetic variability and reduced urinary platinum recovery. A significant sigmoidal relationship existed between ultrafilterable plasma AUC and the percentage of reduction in platelet count (r2 = 0.78). Nonlinear absorption was a limitation to this single-dose schedule of oral NM216; however, little non-haematological toxicity was seen at doses associated with myelosuppression and antitumour activity. Clinical studies of divided dose schedules using doses within the range of pharmacokinetic linearity (< or = 120 mg/m2) are now being investigated.
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Affiliation(s)
- M J McKeage
- Drug Development Section, Institute of Cancer Research, Sutton, Surrey, UK
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Loh S, Skurray R, Célérier J, Bagdasarian M, Bailone A, Devoret R. Nucleotide sequence of the psiA (plasmid SOS inhibition) gene located on the leading region of plasmids F and R6-5. Nucleic Acids Res 1990; 18:4597. [PMID: 2201950 PMCID: PMC331290 DOI: 10.1093/nar/18.15.4597] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- S Loh
- Department of Microbiology, Monash University, Clayton, Victoria, Australia
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Loh S, Ram B. Delayed childbearing in Canada: trends and factors. Genus 1990; 46:147-61. [PMID: 12283645] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/19/2023] Open
Abstract
"Using period and cohort birth order statistics, an overview of the phenomenon of delayed childbearing in Canada is presented. Data employed in the period analysis were mainly from the years 1944 to 1985, while women born between the years 1935 and 1960 were the subjects of the cohort analysis. An examination of selected indices, namely, age-specific first-birth fertility rates, median ages of women at first-order birth and cumulative first-order birth rates shows that there is an overall trend for women to postpone the initiation of childbearing until late twenties or early thirties.... The results indicate that work experience, education, occupation and year of marriage are important variables influencing age at first birth and first-birth interval." (SUMMARY IN FRE AND ITA)
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Loh S, Cram D, Skurray R. Nucleotide sequence of the leading region adjacent to the origin of transfer on plasmid F and its conservation among conjugative plasmids. Mol Gen Genet 1989; 219:177-86. [PMID: 2693941 DOI: 10.1007/bf00261174] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
The leading region of the Escherichia coli K12 F plasmid is the first segment of DNA to be transferred into the recipient cell during conjugal transfer. We report the nucleotide sequence of the 64.20-66.77F portion of the leading region immediately adjacent to the origin of transfer, oriT. The 2582 bp region encodes three open reading frames, ORF95, ORF169 and ORF273; the product of ORF273, is equivalent in size and map location to the 35 kDa protein, 6d, previously described (Cram et al. 1984). S1 nuclease analyses of mRNA transcripts have identified a potential promoter for ORF95 and ORF273 and indicated that these ORFs are transcribed as a single transcript; in contrast, ORF169 appears to be transcribed from two overlapping promoters on the complementary DNA strand. The products of ORF95 and ORF273 are mainly hydrophilic and are probably located in the cytoplasm. ORF273 shares some homology with DNA-binding proteins. There is a signal peptide sequence at the NH2-terminus of ORF169 and the mature form of ORF169 probably resides in the periplasm due to its hydrophilic nature. Both ORF273 and ORF169 are well conserved among conjugative F-like and a few non-F-like plasmids. On the other hand, ORF95 sequences are only present on some of these plasmids. Several primosome and integration host factor recognition sites are present implicating this region in DNA metabolism and/or replication functions.
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Affiliation(s)
- S Loh
- Department of Microbiology, Monash University, Victoria, Australia
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Beran RG, Michelazzi J, Hall L, Tsimnadis P, Loh S. False-negative response rate in epidemiologic studies to define prevalence ratios of epilepsy. Neuroepidemiology 1985; 4:82-5. [PMID: 3831785 DOI: 10.1159/000110218] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
This study has adopted a tested questionnaire, used in a population prevalence study, and distributed it to a sample of people identified as having epilepsy to determine the false-negative response rate for this type of epidemiologic study.
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