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Escherichia coli (E. coli) from the B2 phylogenetic group is implicated in colorectal cancer (CRC) as it possesses a genomic island, termed polyketide synthetase (pks), which codes for the synthesis of colibactin, a genotoxin that induces DNA damage, cell cycle arrest, mutations and chromosomal instability in eukaryotic cells. The aim of this study was to detect and compare the prevalence of E. coli expressing pks (pks+ E. coli) in CRC patients and healthy controls followed by investigating the virulence triggered by pks+ E. coli using an in-vitro model. Mucosal colon tissues were collected and processed to determine the presence of pks+ E. coli. Thereafter, primary colon epithelial (PCE) and colorectal carcinoma (HCT116) cell lines were used to detect cytopathic response to the isolated pks+ E. coli strains. Our results showed 16.7% and 4.3% of CRC and healthy controls, respectively were pks+ E. coli. Further, PCE displayed syncytia and cell swelling and HCT116 cells, megalocytosis, in response to treatment with the isolated pks+ E. coli strains. In conclusion, pks+ E. coli was more often isolated from tissue of CRC patients compared to healthy individuals, and our in-vitro assays suggest these isolated strains may be involved in the initiation and development of CRC.

Investment in stock is a highly risky investment, it is because the existence of randomness in the stock price. In lecture, usually we used Binomial model to price the stock. But, in real world, how do we price the stock? Because the stock price is random, the volatility and drift is a crucial items to behold. The main questions is how to calculate this volatility and drift, and the answer to the question is the sample variance and the sample mean. At any time, the stock price will be either up or down from the previous price. This is where we need a method or model to calculate parameters for up-state and down-state for the stock price. And it will cover the volatility and the drift in an embrace. The method we used in this paper is the Hull-White algorithm. Hull-White algorithm is to find the parameters value of u and d for prediction to stock price. Using SPSS, we will run the data to get the sample variance and sample mean. Then, using Maple 10, we calculate the u and d before enter the value of u and d into programming C++.

Since hard continuous optimization models contain more than one solution and even continuum solution, it is impossible to seek all the solution by using the existent optimization methods. Therefore, in this paper we introduce a co-joint deterministic and probabilistic approach which modifies a soft approach for solving hard continuous optimization models. An algorithm of co-joint approach and several numerical experiments have been presented in this paper. The special numerical test results have shown that the co-joint approach is more effective than soft approach algorithm. Fortunately, we have found that the co-joint algorithm can be used to determine whether the optimization model is hard continuous optimization models or not.

Abstract Background There are limited published studies on patient satisfaction towards endoscopy from Asian countries. Different methods of evaluation of patient satisfaction may yield different results and there is currently no study to compare results of on-site versus phone-back interviews. Method On-site followed by phone-back interviews were carried out on consecutive patients attending the outpatient gastroscopy service of University of Malaya Medical Centre between July 2010 and January 2011 using the modified Group Health Association of America-9 (mGHAA-9) questionnaire. The question on technical skill of endoscopist was replaced with a question on patient comfort during endoscopy. Results Seven hundred patients were interviewed. Waiting times for appointment and on gastroscopy day, and discomfort during procedure accounted for over 90% of unfavorable responses. Favorable response diminished to undesirable level when waiting times for appointment and on gastroscopy day exceeded 1 month and 1 hour, respectively. Satisfaction scores were higher for waiting time for appointment but lower for personal manner of nurses/staff and explanation given during phone-back interview. There was no significant difference in satisfaction scores for other questions, including overall rating between the two methods. Conclusion Waiting times and discomfort during procedure were main causes for patient dissatisfaction. Phone-back interview may result in different scores for some items compared with on-site interview and should be taken into account when comparing results using the different methods.

Abstract Background Risk factors for poor bowel preparation are recognized to be independent of the type of bowel preparation method used. Patient and administrative factors influencing bowel preparation are known to vary in different healthcare systems. Methods A prospective, cross-sectional study of patients undergoing colonoscopy in an Asian tertiary centre was conducted to identify risk factors associated with poor bowel preparation, and to evaluate the impact of poor bowel preparation on technical performance and patient comfort. Results Data on 501 patients (mean age 60.1 ± 14.0 years old, 51.2% males, 60.9% with secondary education or higher) was available for analysis. Poor bowel preparation was present in 151 patients (30.1%). Lower education level (OR = 2.35, 95% CI = 1.54 - 3.60), colonoscopy appointment waiting time beyond 16 weeks (OR = 1.86, 95% CI = 1.04 - 3.37) and non-adherence to bowel preparation instructions (OR = 4.76, 95% CI = 3.00 - 7.55) were identified as independent risk factors for poor bowel preparation. Poor bowel preparation was associated with a lower cecal intubation rate (78.1% versus 98.3%, p < 0.001), prolonged total colonoscopy time (25.4 ± 12.6 minutes versus 16.7 ± 10.2 minutes, p < 0.001), and increased patient discomfort during colonoscopy (patient with moderate to severe abdominal discomfort 31.8% versus 3.2%, p < 0.001). Conclusions Education levels and appointment waiting times, in addition to non-adherence to bowel preparation instructions, increase the risk of poor bowel preparation in adult patients undergoing colonoscopy. The latter has a significant impact on colonoscopy performance and patient comfort.

Abstract Background There is limited data on the nutritional status of Asian patients with various aetiologies of cirrhosis. This study aimed to determine the prevalence of malnutrition and to compare nutritional differences between various aetiologies. Methodology A cross-sectional study of adult patients with decompensated cirrhosis was conducted. Nutritional status was assessed using standard anthropometry, serum visceral proteins and subjective global assessment (SGA). Results Thirty six patients (mean age 59.8 ± 12.8 years; 66.7% males; 41.6% viral hepatitis; Child-Pugh C 55.6%) with decompensated cirrhosis were recruited. Malnutrition was prevalent in 18 (50%) patients and the mean caloric intake was low at 15.2 kcal/kg/day. SGA grade C, as compared to SGA grade B, demonstrated significantly lower anthropometric values in males (BMI 18.1 ± 1.6 vs 26.3 ± 3.5 kg/m2, p < 0.0001; MAMC 19.4 ± 1.5 vs 24.5 ± 3.6 cm, p = 0.002) and females (BMI 19.4 ± 2.7 vs 28.9 ± 4.3, p = 0.001; MAMC 18.0 ± 0.9 vs 28.1 ± 3.6, p < 0.0001), but not with visceral proteins. The SGA demonstrated a trend towards more malnutrition in Child-Pugh C compared to Child-Pugh B liver cirrhosis (40% grade C vs 25% grade C, p = 0.48). Alcoholic cirrhosis had a higher proportion of SGA grade C (41.7%) compared to viral (26.7%) and cryptogenic (28.6%) cirrhosis, but this was not statistically significant. Conclusion Significant malnutrition in Malaysian patients with advanced cirrhosis is common. Alcoholic cirrhosis may have more malnutrition compared to other aetiologies of cirrhosis.

Abstract Background Helicobacter pylori is a major gastric bacterial pathogen. This pathogen has been shown to follow the routes of human migration by their geographical origin and currently the global H. pylori population has been divided into six ancestral populations, three from Africa, two from Asia and one from Europe. Malaysia is made up of three major ethnic populations, Malay, Chinese and Indian, providing a good population for studying recent H. pylori migration and admixture. Results Seventy eight H. pylori isolates, including 27 Chinese, 35 Indian and 16 Malay isolates from Malaysia were analysed by multilocus sequence typing (MLST) of seven housekeeping genes and compared with the global MLST data. STRUCTURE analysis assigned the isolates to previously identified H. pylori ancestral populations, hpEastAsia, hpAsia2 and hpEurope, and revealed a new subpopulation, hspIndia, within hpAsia2. Statistical analysis allowed us to identify population segregation sites that divide the H. pylori populations and the subpopulations. The majority of Malay isolates were found to be grouped together with Indian isolates. Conclusion The majority of the Malay and Indian H. pylori isolates share the same origin while the Malaysian Chinese H. pylori is distinctive. The Malay population, known to have a low infection rate of H. pylori, was likely to be initially H. pylori free and gained the pathogen only recently from cross infection from other populations.

Abstract Background Treatment objectives for dyspepsia include improvements in both symptoms and health-related quality of life (HRQoL). There is a lack of disease-specific instruments measuring HRQoL in South East Asian dyspeptics. Objectives To validate English and locally translated version of the Short-Form Nepean Dyspepsia Index (SF-NDI) in Malaysian patients who consult for dyspepsia. Methods The English version of the SF-NDI was culturally adapted locally and a Malay translation was developed using standard procedures. English and Malay versions of the SF-NDI were assessed against the SF-36 and the Leeds Dyspepsia Questionnaire (LDQ), examining internal consistency, test-retest reliability and construct validity. Results Pilot testing of the translated Malay and original English versions of the SF-NDI in twenty subjects did not identify any cross-cultural adaptation problems. 143 patients (86 English-speaking and 57 Malay speaking) with dyspepsia were interviewed and the overall response rate was 100% with nil missing data. The median total SF-NDI score for both languages were 72.5 and 60.0 respectively. Test-retest reliability was good with intraclass correlation coefficients of 0.90 (English) and 0.83 (Malay), while internal consistency of SF-NDI subscales revealed α values ranging from 0.83 – 0.88 (English) and 0.83 – 0.90 (Malay). In both languages, SF-NDI sub-scales and total score demonstrated lower values in patients with more severe symptoms and in patients with functional vs organic dyspepsia (known groups validity), although these were less marked in the Malay language version. There was moderate to good correlation (r = 0.3 – 0.6) between all SF-NDI sub-scales and various domains of the SF-36 (convergent validity). Conclusion This study demonstrates that both English and Malay versions of the SF-NDI are reliable and probably valid instruments for measuring HRQoL in Malaysian patients with dyspepsia.

Abstract Background There is little information of the validity of generic instruments in measuring health-related quality of life (HRQOL) in patients with dyspepsia. We aimed to assess the reliability and validity of the EQ-5D, a brief and simple instrument, in measuring HRQOL in adult patients with dyspepsia. Methods Consecutive adults with dyspepsia attending the Gastroenterology clinic in a tertiary referral center were interviewed with the EQ-5D (both English and Malay versions), the short-form Nepean Dyspepsia Index (SF-NDI), the SF-36 and Leeds Dyspepsia Questionnaire (LDQ). Known-groups and convergent construct validity were investigated by testing hypotheses at attribute and overall levels. A repeat telephone interview was conducted 2 weeks later to assess test-retest reliability. Results A total of 113 patients (mean (SD) age: 53.7 (14) years; 49.5% male; 24.8% Malays, 37.2% Chinese; 70.8% functional dyspepsia) were recruited. Response rate was 100% with nil missing data. Known-groups validation revealed 20/26 hypotheses fulfillment. Patients with more severe dyspepsia reported more problems with their usual activity (p = 0.07) and pain (p = 0.06) and demonstrated lower median VAS scores (60 vs 70, p = 0.002) and EQ-5D utility scores (0.72 vs 0.78, p = 0.002). Those reporting problems in various EQ-5D dimensions had significantly lower scores in relevant SF-36 and SF-NDI dimensions. The overall EQ-5D utility score also demonstrated good correlation with the SF-36 summary physical and mental scores and the SF-NDI total score. Intraclass correlation coefficient for test-retest reliability was 0.66 (95% CI = 0.55 – 0.76). Conclusion The EQ-5D is an acceptable, valid and reliable generic instrument for measuring HRQOL in adult patients with dyspepsia.

Abstract Background The putative H. pylori pathogenicity-associated factor dupA has been associated with IL-8 induction in vitro, and duodenal ulcer (DU) and gastric cancer (GC) development in certain populations, but this association is inconsistent between studies. We aimed to investigate dupA prevalence in clinical isolates from Sweden, Australia and from ethnic Chinese, Indians and Malays resident in Malaysia and Singapore and to examine the association with DU and GC. In addition we investigated the sequence diversity between isolates from these diverse groups and compared the level of IL-8 secretion in isolates possessing and lacking dupA. Methods PCR primers were designed to amplify over the C/T insertion denoting a continuous dupA. PCR products from 29 clinical isolates were sequenced and compared with sequences from three additional strains obtained from GenBank. Clinical isolates from 21 Malaysian patients (8 dupA-positive, 14 dupA-negative) were assessed for their ability to induce IL-8 in AGS cells in vitro. Statistical analysis was performed using Fisher's exact test. Results The prevalence of dupA in isolates from Swedish functional dyspepsia (FD) control patients (65%, 13/20) was higher and in isolates from Indian FD patients (7.1%, 3/42) was lower as compared with isolates from Chinese (28.9%, 13/49, P = 0.005, P = 0.025), Malay (35.7%, 5/14, P = 0.16, P = 0.018) and Australian (37.8%, 17/45, P = 0.060, P < 0.001) FD patients. dupA was associated with DU and GC development in Chinese with 62.5% (10/16) and 54.6% (12/22) of isolates possessing dupA respectively as compared with FD controls (28.9%) (P = 0.015, P = 0.032). No significant difference in prevalence of dupA between FD controls, DU (63.6%, 7/11) and GC (61.9%, 13/21) cases (P = 1.000) was observed in the Swedish population. Sequence analysis revealed a pairwise variation of 1.9% and all isolates possessed the C/T insertion. The average IL-8 induction was 1330 pg/mL for dupA-positive isolates and 1378 pg/mL for dupA-negative isolates. Conclusion Although dupA is highly conserved when present, we identified no consistent association between dupA and DU or GC development across the ethnic groups investigated, with the dupA prevalence in control groups varying significantly. Our results would suggest that in the clinical isolates investigated dupA is not associated with IL-8 induction in vitro.

This study investigated the association between multidimensional death anxiety and religiosity in multicultural Singapore by examining potential variations by age and gender. We also explored the possibility of a curvilinear effect, where highly religious or non-religious individuals report lower death anxiety than moderately religious people, forming an inverted U-curve pattern. Data were collected from 110 participants using questionnaires that assessed death anxiety and religiosity. Parametric and non-parametric tests were then conducted. The findings showed that women had significantly higher death anxiety and religiosity than men, and highly and moderately religious people had significantly higher death anxiety than non-religious people. People of all age groups had similar levels of death anxiety. These findings highlight the importance of developing targeted death anxiety interventions that integrate spiritual aspects in Singapore so that clinicians can provide culturally competent care., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Belak and Goh.)

Objectives: There is lack of evidence-based information on the use and timing of endotracheal intubation (ETI) in children with prehospital status epilepticus (SE)., Methods: The aim of this study was to investigate ETI use, timing, risk factors, and outcomes in children presenting to a single-center children's emergency (CE) with prehospital SE, over a 5-year period., Results: A total of 118 events involving children presenting to CE with ongoing prehospital SE were included, and 39% (46/118) of the events required ETI. The most common indication for ETI was respiratory depression. The median time to intubation after arrival at CE was 20.0 minutes (1-155 minutes). Risk factors associated with ETI use include the administration of more than 2 benzodiazepines (26.1% vs 4.2%, P < 0.001) and the use of second- or third-line antiepileptic therapy ( P < 0.001). The use of more than 2 doses of benzodiazepines was found in 12.7% (15/118) of the patients. In patients who received excessive benzodiazepines, 87% (13/15) of them required intubation., Conclusions: Excessive use of benzodiazepine was found to be a main risk factor for ETI in patients with prehospital SE. Avoidance of the excessive use of benzodiazepines and adhering to clinical management guidelines may reduce the risk for ETI in the CE. The best approach to airway management in children with prehospital SE is lacking and urgently needed., Competing Interests: Disclosure: The authors declare no conflict of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Background: Prior literature suggests that alert dismissal could be linked to physicians' habits and automaticity. The evidence for this perspective has been mainly observational data. This study uses log data from an electronic medical records system to empirically validate this perspective., Objective: We seek to quantify the association between habit and alert dismissal in physicians., Methods: We conducted a retrospective analysis using the log data comprising 66,049 alerts generated from hospitalized patients in a hospital from March 2017 to December 2018. We analyzed 1152 physicians exposed to a specific clinical support alert triggered in a hospital's electronic medical record system to estimate the extent to which the physicians' habit strength, which had been developed from habitual learning, impacted their propensity toward alert dismissal. We further examined the association between a physician's habit strength and their subsequent incidences of alert dismissal. Additionally, we recorded the time taken by the physician to respond to the alert and collected data on other clinical and environmental factors related to the alerts as covariates for the analysis., Results: We found that a physician's prior dismissal of alerts leads to their increased habit strength to dismiss alerts. Furthermore, a physician's habit strength to dismiss alerts was found to be positively associated with incidences of subsequent alert dismissals after their initial alert dismissal. Alert dismissal due to habitual learning was also found to be pervasive across all physician ranks, from junior interns to senior attending specialists. Further, the dismissal of alerts had been observed to typically occur after a very short processing time. Our study found that 72.5% of alerts were dismissed in under 3 seconds after the alert appeared, and 13.2% of all alerts were dismissed in under 1 second after the alert appeared. We found empirical support that habitual dismissal is one of the key factors associated with alert dismissal. We also found that habitual dismissal of alerts is self-reinforcing, which suggests significant challenges in disrupting or changing alert dismissal habits once they are formed., Conclusions: Habitual tendencies are associated with the dismissal of alerts. This relationship is pervasive across all levels of physician rank and experience, and the effect is self-reinforcing., (©Le Wang, Kim Huat Goh, Adrian Yeow, Hermione Poh, Ke Li, Joannas Jie Lin Yeow, Gamaliel Tan, Christina Soh. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 16.02.2022.)

Objective: To measure the psychological well-being of healthcare workers (HCWs) during this COVID-19 pandemic and examine the experiences of the subgroup of participants who were also HCWs during the 2003 SARS epidemic., Design: Anonymous online survey adapted from a similar study conducted during the SARS epidemic, disseminated from July 2020 to August 2020., Setting: Nine healthcare institutions across Singapore ranging from primary care, community care, tertiary care and specialised referral centres., Participants: Employees working in the participating healthcare institutions., Results: Of 3828 survey returns, 3616 had at least one completed item on the questionnaire. Majority were female (74.7%), nurses (51.7%), foreign-born (53.2%) and not working in the tertiary care setting (52.1%). The median score on the Impact of Events Scale (IES) was 15 (IQR 23) and 28.2% of the sample scored in the moderate/severe range. 22.7% of the participants were also HCWs during SARS and more than half of them felt safer and better equipped in the current pandemic. 25.2% of SARS HCWs and 25.9% of non-SARS HCWs had moderate/severe IES scores (p=0.904). After adjusting for age, marital status, parity and length of work experience, racial minority groups and living apart from family were independent predictors of high IES regardless of prior SARS epidemic experience. Daily exposure to confirmed or suspect COVID-19 cases increased the odds of high IES for non-SARS HCWs only., Conclusions and Relevance: Overall, while 28% of HCWs in our study suffered from significant trauma-related psychological symptoms regardless of prior experience with the SARS epidemic, those with prior experience reported feeling safer and better equipped, finding the workload easier to manage, as well as having more confidence in their healthcare leaders. We recommend for more trauma-informed support strategies for our HCWs especially those from racial minority groups, who are foreign-born and isolated from their families., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Prior literature suggests that psychosocial factors adversely impact health and health care utilization outcomes. However, psychosocial factors are typically not captured by the structured data in electronic medical records (EMRs) but are rather recorded as free text in different types of clinical notes., Objective: We here propose a text-mining approach to analyze EMRs to identify older adults with key psychosocial factors that predict adverse health care utilization outcomes, measured by 30-day readmission. The psychological factors were appended to the LACE (Length of stay, Acuity of the admission, Comorbidity of the patient, and Emergency department use) Index for Readmission to improve the prediction of readmission risk., Methods: We performed a retrospective analysis using EMR notes of 43,216 hospitalization encounters in a hospital from January 1, 2017 to February 28, 2019. The mean age of the cohort was 67.51 years (SD 15.87), the mean length of stay was 5.57 days (SD 10.41), and the mean intensive care unit stay was 5% (SD 22%). We employed text-mining techniques to extract psychosocial topics that are representative of these patients and tested the utility of these topics in predicting 30-day hospital readmission beyond the predictive value of the LACE Index for Readmission., Results: The added text-mined factors improved the area under the receiver operating characteristic curve of the readmission prediction by 8.46% for geriatric patients, 6.99% for the general hospital population, and 6.64% for frequent admitters. Medical social workers and case managers captured more of the psychosocial text topics than physicians., Conclusions: The results of this study demonstrate the feasibility of extracting psychosocial factors from EMR clinical notes and the value of these notes in improving readmission risk prediction. Psychosocial profiles of patients can be curated and quantified from text mining clinical notes and these profiles can be successfully applied to artificial intelligence models to improve readmission risk prediction., (©Kim Huat Goh, Le Wang, Adrian Yong Kwang Yeow, Yew Yoong Ding, Lydia Shu Yi Au, Hermione Mei Niang Poh, Ke Li, Joannas Jie Lin Yeow, Gamaliel Yu Heng Tan. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 19.10.2021.)

Sepsis is a leading cause of death in hospitals. Early prediction and diagnosis of sepsis, which is critical in reducing mortality, is challenging as many of its signs and symptoms are similar to other less critical conditions. We develop an artificial intelligence algorithm, SERA algorithm, which uses both structured data and unstructured clinical notes to predict and diagnose sepsis. We test this algorithm with independent, clinical notes and achieve high predictive accuracy 12 hours before the onset of sepsis (AUC 0.94, sensitivity 0.87 and specificity 0.87). We compare the SERA algorithm against physician predictions and show the algorithm's potential to increase the early detection of sepsis by up to 32% and reduce false positives by up to 17%. Mining unstructured clinical notes is shown to improve the algorithm's accuracy compared to using only clinical measures for early warning 12 to 48 hours before the onset of sepsis.

Dysphagia increases risk of pneumonia in patients with Parkinson's disease (PD). However, no studies have investigated the association between objective measures of swallowing dysfunction and clinical outcomes. Therefore, we aimed to study the link between scores obtained on the modified barium swallow impairment scale profile (MBSImP) and hospital admissions for pneumonia and choking, in groups of patients with PD on different feeding modes. 157 patients who completed MBS studies were divided into three groups based on their feeding modes (oral, enteral, and rejected enteral feeding with oral feeding at own risk). Videos were analysed using the MBSImP. We evaluated the association of the oral, pharyngeal, and combined scores, with risk of admission for pneumonia and choking. Kaplan-Meier plots and log-rank tests were used to compare survival distributions among feeding groups. Cox regression models were generated to estimate hazard ratios (HRs) and 95% confidence intervals. Patients in the group that rejected enteral feeding scored the highest on the MBSImP, followed by enteral then oral feeding. Within the group that rejected enteral feeding, higher pharyngeal (HR = 3.73, p = 0.036) and combined scores (HR = 1.63, p = 0.034) significantly increased the risk of pneumonia and choking. In the enteral feeding group, higher oral subscores (HR = 2.16, p = 0.011) increased risk for the event, while higher pharyngeal (HR = 0.40, p = 0.004) subscores reduced risk for pneumonia and choking. This is the first study to analyse the association of MBSImP scores with clinical outcomes in PD patients. Patients who rejected enteral feeding had the highest risk for pneumonia and choking that could be predicted by their MBSImP scores. In the enteral feeding group, this risk was partially reversed. Compliance with feeding modes reduces the risk of pneumonia and choking.

Objective: To evaluate the time to hospitalisation and baseline factors associated with pneumonia/choking in Parkinson's Disease (PD) patients., Background: Although dysphagia and pneumonia are common problems in PD, scarce research has been performed., Methods: A total of 194 PD patients who underwent a VFS evaluation were retrospectively selected. The mode of feeding and admissions for pneumonia/choking were analyzed. Baseline clinical and demographic variables were compared between feeding groups. Kaplan-Meier survival analysis was performed to estimate time to pneumonia/choking. Clinical variables significantly associated with pneumonia/choking free survival were identified using Cox regression., Results: Hospitalisation for pneumonia/choking occurred in 89 out of 194 patients, with the highest admission rate in rejected enteral feeding group (66.7%), followed by enteral feeding (61.8%) and oral feeding (38.8%) groups. The estimates of median time to event were 11, 14, and 47 months for rejected enteral feeding, enteral and oral feeding groups respectively (log-rank test p < 0.001). The rejected enteral feeding group had the highest risk of pneumonia/choking (HR 4.61, 95%CI:2.33-9.08, p < 0.001), followed by enteral feeding group (HR 2.29, 95%CI:1.25-4.19, p = 0.007), when compared to oral feeding group after adjusting for possible confounders. A stepwise Cox regression showed that the rejected enteral feeding (HR 4.89, 95%CI:2.19-10.88, p < 0.001), enteral mode of feeding (HR 2.43, 95%CI:1.11-5.32, p = 0.026), and Charlson weighted index of co-morbidity (HR 1.27, 95%CI:1.03-1.58, p = 0.028) were independently associated with higher hazard of pneumonia/choking., Conclusions: Compliance to feeding recommendations is important to reduce the risk of hospitalisation for pneumonia/choking. The recommended mode of feeding and comorbidity index was significantly associated with pneumonia/choking risk., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

This study compared bite force in adults older than 60 years with that of young adults. The participants were 20 healthy adults (9 men) older than 60 years (median age, 66 years) and 44 healthy young adults (22 men; age range, 18-25 years; median age, 22 years) at the International Medical University, Malaysia. All participants had at least 20 teeth, and bite force was measured and evaluated using the Dental Prescale system. Average (SD) bite force was 420.5 (242.0) N for the older adults and 541.4 (296.3) N for the young adults. Although mean bite force was higher for the young adults, the difference was not significant. These findings suggest that bite force is unaffected by age in adults with adequate dentition. (J Oral Sci 58, 361-363, 2016).

Background: Endovascular repair of thoracic aortic pathology has become increasingly common over the last decade. We highlight the case of an intentionally occluded left subclavian artery stump acting as a source of emboli after thoracic endovascular aneurysm repair (TEVAR) for type B dissection., Methods: A 68-year-old man underwent TEVAR of a type B thoracic aortic dissection. A carotid subclavian bypass was performed, and an AMPLATZER™ endovascular plug (to occlude the left subclavian artery origin) was used to create an adequate proximal landing zone., Results: The patient presented with a posterior circulation stroke 2 years later, which was thought to be due to emboli originating from the occluded subclavian artery stump., Conclusions: Consideration should be given to ligating the subclavian artery immediately proximal to the vertebral artery origin when performing adjunctive carotid subclavian bypass during TEVAR. If this is not done, surveillance computed tomography scans should monitor for the development of propagating thrombus in the subclavian stump., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Lorong Halus, Singapore's first landfill leachate treatment system, consists of a pre-treatment system (8,000 m(2)), five constructed reed beds (38,000 m(2)), five polishing ponds (13,000 m(2)), an education centre and a learning trail for visitors. Eight species of wetland plants (total 160,000 plants) were selected for their ability to uptake nutrients, tolerance to low phosphorus concentrations and resistance to pest infestations. The wetland was launched in March 2011 and water quality monitoring started in April 2011. The removal efficiencies of the pre-treatment system from April 2011 to August 2012 are biochemical oxygen demand (BOD5) 57.4%; chemical oxygen demand (COD) 23.6%; total suspended solids (TSS) 55.1%; ammoniacal nitrogen (NH4-N) 76.8%; total phosphorus (TP) 33.3% and total nitrogen (TN) 60.2%. Removal efficiencies of the reed beds are BOD5 47.0%; COD 42.2%; TSS 57.0%; NH4-N 82.5%; TP 29.3% and TN 83.9%. Plant growth is generally satisfactory, but the lower than designed volume of leachate has adversely affected some sections of plants and resulted in uneven flow distribution in reed beds. The plant management programme includes improving plant regrowth by harvesting of alternate strips of plants and replanting. The treated effluent meets water quality limits for discharge to the public sewer and is subsequently treated by the NEWater treatment system, which recycles water for industrial and indirect potable use.

The influences of common oxyanions (i.e. nitrate, silica, sulfate, carbonate, and phosphate) and natural organic matter (NOM) on the sorption of arsenate, chromate, bromate and vanadate (toxic oxyanions) by nanocrystalline Mg/Al layered double hydroxide (LDH) were investigated. Besides the type and concentration of the co-existing species, sorption competition was greatly dependent on the solution pH. In general, based on their sorption competitiveness with the toxic oxyanions, the co-existing common oxyanions were ranked in the order of nitrate < silica < or = sulfate < carbonate < phosphate, while the toxic oxyanions could be ranked in the order of bromate < arsenate approximately chromate < or = vanadate, indicating the oxyanions with lower ionic potentials were less preferably sorbed by the LDH. Based on the comprehensive study on sorption of arsenate by the LDH, the decrease in sorption of toxic oxyanions could be attributed to the competition of common oxyanions for common sorption sites on the LDH which predominantly occurred via ion exchange mechanism. NOM inhibited toxic oxyanion sorption through shielding LDH surface sites, directly competing for sorption sites of LDH, and co-precipitating the LDH. The presence of common oxyanions and NOM generally did not affect the mineral stability of the nanocrystalline LDH., (Copyright 2010 Elsevier B.V. All rights reserved.)

The sorption ability of fast-coprecipitated and hydrothermally-treated Mg/Al layered double hydroxide nanoparticles (FCHT-LDH) for various oxyhalides and oxyanions was evaluated. Interactions of oxyhalide such as monovalent bromate or oxyanions such as divalent chromate and divalent vanadate with FCHT-LDH were investigated using a combination of macroscopic (batch sorption/desorption studies and electrophoretic mobility (EM) measurements) and microscopic techniques (CHNS/O, XRD, FTIR, XPS, and EXAFS analyses). The sorption studies on various oxyanions and oxyhalides suggested that their sorption characteristics on FCHT-LDH were largely governed by their ionic potentials and molecular structures. Oxyanions which have ionic potentials higher than 7 nm(-1) were found to be more readily sorbed by FCHT-LDH than oxyhalides with ionic potentials lower than 5 nm(-1). The results obtained also demonstrated that trigonal pyramid oxyhalides showed a lower degree of specificity for FCHT-LDH than the tetrahedral coordinated oxyanions. From the macroscopic and microscopic studies, monovalent oxyhalide sorption on FCHT-LDH was postulated to occur mainly via anion exchange mechanism with subsequent formation of outer-sphere surface complexes. For polyvalent oxyanion sorption on FCHT-LDH, the mechanisms were possibly associated with both anion exchange and ligand exchange reactions, resulting in the coexistence of outer-sphere and inner-sphere surface complexes., (2010 Elsevier B.V. All rights reserved.)

Adipose tissue is a highly active endocrine organ secreting a variety of signaling molecules called adipokines. Leptin and resistin are two adipokines critically involved in metabolic homeostasis. Nevertheless, the secretory pathways of these adipokines and their interplays are poorly elucidated. In this work, we have comparatively studied several key aspects of leptin and resistin secretion from 3T3-L1 adipocytes. It was found that leptin and resistin molecules are compartmentalized into different secretory vesicles. The trafficking of leptin and resistin vesicles, and the secretion of leptin and resistin are oppositely regulated by insulin/glycolytic substrates and cAMP/protein kinase A. Interestingly, these two adipokines adversely influence each other on secretion and vesicle trafficking. Finally, we demonstrated that both leptin and resistin secretion are Ca(2+) dependent.

Objectives: There continues to be a debate about the long-term prognosis of psychiatric treatment of depression in later life. There have been no long-term naturalistic studies of psychiatric outpatient treatment of older adults in the United States. This study examines outcome and predictors of various levels of depression among a biracial sample of geropsychiatric outpatients in Brooklyn, NY., Methods: We conducted a naturalistic study (median: 33 months) of 143 persons aged 55 and over with diagnoses of depression drawn from 15 psychiatry outpatient clinics and 2 geriatric day programs. Their mean age was 68 years, 87% were female, and 43% were white and 57% were black, among whom 37% were African Caribbeans. Using George's Social Antecedent Model of Depression, we examined the impact of 15 predictor variables on two outcome measures: presence of any either subclinical or clinical depression (CES-D score > or = 8) and presence of clinical depression (CES-D score > or = 16)., Results: On follow-up, 84% and 90% of subclinically and clinically depressed persons at baseline, respectively, were depressed (CES-D > or = 8); 62% of those in remission at baseline were depressed. In logistic regression, 3 variables were significant predictors of any level of depression on follow-up: baseline depression, baseline anxiety, greater increase in anxiety symptoms during the follow-up period. These 3 variables along with financial strain were significant predictors of clinical depression on follow-up. There were no inter- or intra-racial differences in outcome., Conclusions: The bleak outcome findings among older psychiatric outpatients in Brooklyn were consistent with unfavorable results reported in European studies. Because there were only a few predictors of outcome, strategies that target high risk persons - e.g., such as those with subclinical depression, anxiety, or in more economic distress - may prevent transition to severe and persistent depressive states., (Copyright 2009 Elsevier B.V. All rights reserved.)

Removal of arsenate (As(V)) from aqueous solution using both nanocrystalline and coprecipitated Mg/Al layered double hydroxides (LDHs) was examined under different sorption/desorption conditions. The surface area, pore volume, and pore size of the nanocrystalline LDH were significantly higher than those of the coprecipitated LDH, thus resulting in a higher As(V) sorption maximum than the coprecipitated LDH. The calculated activation energy (E(a)) value was 24.7 kJ/mol, suggesting the occurrence of anion exchange process for As(V) removal by the nanocrystalline LDH. The predominance of anion exchange process was further supported by the investigation of ionic strength effect, and XRD and FTIR analyses. The effect of aqueous matrix on As(V) sorption by the nanocrystalline LDH was found to increase in the order of nitrate < silica < sulfate < carbonate < phosphate. Regeneration study showed that a secondary sorption mechanism might occur concurrently for the As(V) sorption by nanocrystalline LDH besides the predominant anion exchange process. Prospects and challenges for practical application of the nanocrystalline LDH were also discussed in the latter part of this study.

Objectives: There are a paucity of long-term studies from the United States concerning predictors of outcome among depressed older community adults. This article examines predictors of depression in a biracial sample of older persons in Brooklyn, NY., Methods: The authors conducted a naturalistic study of 110 persons aged 55 years and older living in randomly selected block groups who had a Center for Epidemiologic Studies-Depression (CES-D) score of > or = 8 at baseline. Persons were reassessed on an average of 3 years later. Their mean age was 69 years, 52% were women, and 35% were whites, and 65% were blacks, among whom 71% were African Caribbeans. Using George's Social Antecedent Model of Depression, the authors examined the impact of 13 predictor variables on two outcome measures: presence of either subsyndromal or syndromal depression (CES-D score > or = 8) and presence of syndromal depression (CES-D score > or = 16). To control for design effects, the authors used SUDAAN for the data analysis., Results: On follow-up, 82% and 88% of subsyndromally and syndromally depressed persons at baseline, respectively, were depressed (CES-D > or = 8). In logistic regression, baseline depressive symptoms, baseline anxiety symptoms, greater increase in anxiety symptoms during the follow-up period, and higher locus of control were predictors of any level of depression. These four variables along with greater paranoid ideation and/or psychoses and more reliable social contacts were significant predictors of syndromal depression on follow-up. There were no inter- or intraracial differences in outcome., Conclusion: Depressed community elders in Brooklyn have highly unfavorable outcomes. Preventive strategies that target at-risk persons-i.e., especially those with baseline subsyndromal depression, greater anxiety symptoms, and more paranoid ideation and/or psychoses-may reduce the development of severe or persistent depression.

A nanocrystalline Mg/Al layered double hydroxide (FCHT-LDH) adsorbent was developed and investigated through stoichiometric calculations, nitrate displacement investigation, comprehensive sorption/desorption experiments, and analyses with XPS, XRD, FTIR, CHNS/O, and EDX for better understanding of the predominant nature of arsenate (As(V)) interaction with FCHT-LDH. FCHT-LDH demonstrated a higher sorption capacity and a faster sorption rate compared to the layered double hydroxides (LDHs) prepared by conventional methods, due to its higher surface area, better porosity characteristics, and nanocrystalline property. These results also indicated the important role of hydrothermal treatment during the synthesis process for enhanced As(V) removal. The observed nitrate-arsenate molar displacement ratio, increased interlayer spacing, and decreased nitrogen content in the interlayer region revealed the predominance of anion exchange mechanism in As(V) sorption by FCHT-LDH. However, a slight pH increase during As(V) sorption equalization and the presence of ca. 25% irreversibly sorbed As(V) signified the occurrence of ligand exchange process as the secondary sorption mechanism. This specific sorption process that possibly involved formation of inner-sphere As(V) complexes with a monodentate mononuclear configuration at the aluminum center, rendered the FCHT-LDH a high affinity for As(V) over nitrate but induced hysteretic sorption/desorption characteristic that limited its regenerated sorption capacity.

In this study, Mg/Al layered double hydroxides (LDHs) were investigated for their potential in scavenging several harmful oxyanions from aqueous solution. LDHs could effectively remove oxyanions and the selectivity of LDHs was governed by both the valencies and the ionic radii of the oxyanions. LDHs prepared by the fast coprecipitation with hydrothermal treatment (FCHT) method and sol-gel with solvothermal treatment method (SGST) had higher oxyanion (i.e. arsenate) removal efficiency than those prepared by the conventional routes, owing to their lower carbonate content, higher surface area, larger pore volume, larger pore size, and nanocrystalline characteristic. The sorption of arsenate by FCHT-LDH was found primarily due to anion exchange mechanism and might involve a secondary sorption mechanism. The negative DeltaG degrees for arsenate sorption confirmed the spontaneity of the removal process. The positive values of DeltaH degrees and DeltaS degrees provided further evidence of the anion exchange process in the removal mechanism.

Layered double hydroxides (LDHs) are lamellar mixed hydroxides containing positively charged main layers and undergoing anion exchange chemistry. In recent years, many studies have been devoted to investigating the ability of LDHs to remove harmful oxyanions such as arsenate, chromate, phosphate, etc. from contaminated waters by both surface adsorption and anion exchange of the oxyanions for interlayer anions in the LDH structure. This review article provides an overview of the LDH synthesis methods, the LDH characterization techniques, and the recent advancement that has been achieved in oxyanion removal using LDHs, highlighting areas of consensus and currently unresolved issues. Experimental studies relating to the sorption behaviors of LDHs with various oxyanions, and the kinetic models adopted to explain the adsorption rate of oxyanions from aqueous solution onto LDHs, have been comprehensively reviewed. This review discusses several key factors such as pH, competitive anions, temperature, etc., that influence the oxyanion adsorption on LDHs. The reusability of LDHs is discussed and some mechanistic studies of oxyanion adsorption on LDHs are highlighted. The sorption capacities of LDHs for various oxyanions are also compared with those of other adsorbents. In addition, this review critically identifies the shortcomings in current research on LDHs, such as the common weaknesses in the adopted methodology, discrepancies among reported results and ambiguous conclusions. Possible improvement of LDHs and potential areas for future application of LDHs are also proposed.

This study aimed to establish an optimized, closed loop application of ethylenediaminetetraacetic acid (EDTA) in heavy metal removals from a contaminated soil through integrating EDTA recovery/regeneration and metal precipitation processes in the treatment train. Three divalent heavy metals were investigated, namely, Pb, Cd, and Ni. The extractability of the metals by EDTA followed the decreasing order of CdPb>>Ni. The first part of this study was to search for the optimal use of the fresh EDTA in removing these heavy metals from the contaminated soil. The second part of this study was devoted to the recovery/regeneration of the spent EDTA which followed the sequential processes involving (1) complex destabilization by adding ferric ion (Fe(III)) to liberate Pb, Cd, and Ni, (2) precipitation of the liberated Pb, Cd, and Ni in phosphate (PO4(3-)) forms, and (3) precipitation of the excess Fe(III) which eventually produced free EDTA for reuse. The process variables were dosages of Fe(III) and PO4(3-), pH and reaction times. Laborious trial experiments would be needed in searching for the optimum conditions for the above processes. To expedite this exercise, a geochemical equilibrium model, MINTEQA2, was used to find the thermodynamically favorable conditions for recoveries of both EDTA and heavy metals. This was then followed by experimental examination of the process kinetics to observe for the optimal reaction time for each thermodynamically favorable process. This study revealed that 2 h of reaction time each for the complex destabilization reaction and the metal phosphate precipitation reaction was sufficient to achieve equilibrium. With the optimized process condition identified in this study, a total of 95%, 89% and 90% of the extracted Pb, Cd and Ni, respectively, could be precipitated from the spent EDTA solution, with 84% EDTA recovery. The reused EDTA maintained more than 90% of its preceding extraction power in each cycle of reuse.

Two batches of fine soil fraction of an acidic soil were deliberately contaminated with selenite (Se(IV)) and selenate (Se(VI)), respectively, and aged for more than 220 days. Speciation analysis using continuous flow-through hydride generation atomic absorption spectrometry (HGAAS) indicated that the species were predominant in their respective aged soils. A selective sequential extraction scheme was employed to fractionate the Se retained in the soils into six fractions of varying retentions. Abilities of various chemical reagents in extracting the Se in the two soil batches were then evaluated. The reagents investigated were sodium salts such as sodium chloride (NaCl), sodium sulfate (Na2SO4), sodium carbonate (Na2CO3), and sodium phosphate (Na3PO4), and two oxidants, namely, hydrogen peroxide (H2O2) and potassium permanganate (KMnO4). It was found that NaCl, Na2SO4, and Na2CO3 could only extract the exchangeable fraction of Se, while Na3PO4 could extract the exchangeable and strongly-bound fractions. Selenate was extracted more than Se(IV) by the salts. The kinetics of Se(IV) extraction by Na3PO4 could be best described by the Elovich model, while the Ritchie second-order model was the most appropriate to describe Se(VI) extraction. Efficiencies of the oxidants in Se(IV) extraction highly depended on their applied dosages. Both H2O2 and KMnO4 were able to extract greater than 93% of total Se, and therefore were significantly more effective than the salts in Se(IV) extraction.

Factors that can affect As and Se adsorption by soils influence the bioavailability and mobility of these elements in the subsurface. This research attempted to compare the adsorption capacities of As(III), As(V), Se(IV), and Se(VI) on a tropical soil commonly found in Singapore in a single-species system. The effect of reaction time, pH, and competitive anions at different concentrations on the adsorption of both As and Se species were investigated. The As and Se adsorption isotherm were also obtained under different background electrolytes. The batch adsorption experiments showed that the sequence of the As and Se adsorption capacities in the soil was As(V) > Se(IV) > As(III) > Se(VI). The adsorption kinetics could be best described by the Elovich equation. The adsorption of As(V), Se(IV), and Se(VI) appeared to be influenced by the variable pH-dependent charges developed on the soil particle surfaces. Phosphate had more profound effect than SO4(2-) on As and Se adsorption in the soil. The competition between PO4(3-) and As or Se oxyanions on adsorption sites was presumably due to the formation of surface complexes and the surface accumulation or precipitation involving PO4(3-). The thermodynamic adsorption data for As(V) and Se(IV) adsorption followed the Langmuir equation, while the As(III) and Se(VI) adsorption data appeared to be best-represented by the Freundlich equation.

Objective: To determine whether the average doses of inhaled beclomethasone, fluticasone and budesonide prescribed in primary care reflect the relative potencies of these medicines., Methods: Retrospective analysis of 95,540 prescriptions for inhaled steroids written by 293 general practitioners in Auckland, New Zealand, between November 1995 and June 1998. In addition, 177 general practitioners were presented with two case histories describing patients with uncontrolled asthma who were not on treatment with inhaled steroids. They were asked which medicine they would prescribe and in what dose., Results: The average daily doses prescribed were 600 microg for fluticasone, 747 microg for beclomethasone and 1184 microg for budesonide. The average dose of fluticasone was 80% of that for beclomethasone. In May 1997, when 4.5% of the prescriptions for inhaled steroids were for fluticasone, the average doses of fluticasone and beclomethasone were 632 microg and 760 microg, respectively. By May 1998, when 23% of prescriptions were for fluticasone, the average doses of fluticasone and beclomethasone were little changed at 610 microg and 726 microg, respectively. In response to the two case histories, the average doses of fluticasone chosen were 71% and 77% of the doses of beclomethasone., Conclusions: The average prescribed dose of fluticasone was 80% of that for beclomethasone, even though fluticasone is at least twice as potent as beclomethasone. Similar findings were observed when the general practitioners responded to the case histories. The high doses of fluticasone prescribed may be due to a failure to appreciate that fluticasone is twice as potent as beclomethasone and to the availability of high strength preparations of fluticasone, i.e. 250 microg per actuation.

Serum concentrations of thyroid stimulating hormone (TSH) and thyroid autoantibodies in pregnant patients with thyroid disease at various stages of pregnancy were determined by in-house ELISAs. In normal pregnancy, serum TSH levels were significantly elevated (p < 0.05) from 13 weeks of gestation. The normal reference ranges for TSH for the second (0.6-5.0 mIU/l) and third trimester (0.6-5.6 mIU/l) were significantly higher (p < 0.05; p < 0.01 respectively) compared to 0.4-4.5 mIU/l for the first trimester. In pregnant thyroid patients, serum TSH levels correlated highly (p < 0.001) to T4 (r = 0.740), FT4I (r = 0.683) and MicAb (microsomal antibodies) (r = 0.825) but weaker (p < 0.01) to T3 (r = -0.512), FT3I (r = 0.520) and TgAb (thyroglobulin antibodies) (r = 0.618). Thus, measurement of TSH with the highly sensitive ELISA (enzyme linked immunosorbent assay) would form a useful first line test for thyroid dysfunction in pregnancy while measurement of thyroid autoantibodies would aid in the diagnosis of autoimmune hypothyroidism.

A supersensitive ELISA was developed for measurement of thyroid-stimulating hormone (TSH) concentrations in serum using in-house rabbit polyclonal antisera and a commercial monoclonal antibody. The assay was optimised and validated by recovery, linearity and cross-reactivity experiments and further compared to other available assays and EQAS samples. Good precision was obtained with a working assay range of 0.2 to 100 mIU/L with < 10% coefficient of variation (CV) for both intra and interassay. The assay is highly sensitive and specific with a minimum detectable limit of 0.07 mIU/L and negligible cross-reactivities against LH, FSH, HCG and other pituitary peptides. Good correlations were obtained when compared to Abbott hTSH EIA (r = 0.993; p < 0.001; n = 85) and NETRIA IRMA (r + 0.995; p < 0.001; n = 76). The normal reference range established was 0.4 to 4.0 mIU/L (n = 76). TSH levels in serum of thyrotoxic patients (n = 83) were significantly lower (0.07 to 0.20 mIU/L, p < 0.0001) and completely distinct from normal values thereby obviating the requirement of a TRH-stimulation test. Stability studies showed that coated wells can be stored at 4 degrees C for at least 2 months. This highly sensitive in-house hTSH ELISA which is cheap, stable and readily available is useful for diagnosis and management of patients with various thyroid disorders.

A standard 40 mm arteriotomy was created in canine iliac and carotid arteries and then closed by either direct suture without a patch, with a vein patch or with a polytetrafluoroethylene patch (PTFE). The uptake of 111-Indium oxine labelled platelets at 2 hours after operation was compared between the groups. Arteriotomies closed with a PTFE patch demonstrated significantly greater platelet aggregation than those closed with a vein patch. Primary closure without a patch was associated with the least platelet uptake of all (PTFE versus vein patch, P less than 0.01; PTFE versus no patch, P less than 0.01; vein patch versus no patch, P less than 0.05). Light and electron microscopy confirmed the radioisotopic findings.

Over a two year period 80 patients were entered into a prospective randomized trial comparing polytetrafluoroethylene (PTFE) and Dacron infrarenal aortic reconstructions. Fifty-four patients were treated for aneurysm (30 single tubed grafts; 24 bifurcation grafts), and 26 patients were treated for occlusive disease (26 bifurcation grafts). The groups were matched for age, sex and preoperative risk factors. Five patients died after operation (6.3%) including two from hemorrhage, but there were no significant differences in mortality and morbidity between the PTFE and Dacron groups. The volume of blood lost at operation (1930 +/- 1340 ml, all patients); the volume of blood transfused (2.98 +/- 2.43 units); the volume of crystalloids infused (3050 +/- 1390 ml); the intraoperative heparin dosage (67.9 +/- 20.5 mg); the clamp time (71.6 +/- 34.5 min); and the total operating time (228.1 +/- 78.3 min) also showed no significant differences between PTFE and Dacron. The ankle systolic pressure index rose more for PTFE (0.96 +/- 0.24) than for Dacron (0.82 +/- 0.20; P less than 0.002) at the time of discharge. This partially reflects a difference in the index between the groups before operation (PTFE 0.79 +/- 0.30; Dacron 0.72 +/- 0.32), but it may also indicate that PTFE is less thrombogenic than Dacron.

To evaluate the perioperative outcomes and the immediate increases in size after patch closure, 140 carotid endarterectomies were randomized into one of three groups: direct no-patch closure, saphenous vein patch closure, and polytetrafluoroethylene patch closure. Seven patients (4.4%) experienced signs of cerebral ischemia in the immediate postoperative period. In three cases this was transient and reversible. In the other four reexploration was undertaken and carotid thrombosis was corrected by thrombectomy. The condition of one of these patients deteriorated to a permanent stroke, whereas the other patients made a complete recovery. Neurologic complications were more frequent in the no-patch group, but the differences between the groups were not significant. The incidence of perioperative internal carotid stenosis, aneurysmal dilatation, and other morphologic abnormalities was assessed in 131 intravenous digital subtraction angiograms taken before the patient was discharged from the hospital. Eight (17.0%) of the endarterectomies in the no-patch group were narrowed by 30% to 50% diameter stenosis, whereas none of the patched arteries had more than 30% stenosis. In contrast, dilatation of the common or internal carotid artery to more than twice the measured diameter was absent in non-patched arteries but was present in seven (17.0%) saphenous patch closures and four (9.23%) polytetrafluoroethylene patch closures. We conclude that patch closure after carotid endarterectomy is less likely to cause stenosis in the perioperative period. Poly-tetrafluoroethylene patches resist dilatation better than do saphenous vein patches and are less likely to become aneurysmal.