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Biomedical subjects

A Chao

Publications and source records attributed to A Chao.

At least 19 recordsLinked to original sources

Hepatic encephalopathy and cerebral blood flow improved by liver dialysis treatment.

Eight acute liver failure patients, all in grade IV hepatic encephalopathy, were administered liver dialysis treatment with the Hemo Therapies Unit (Hemo Therapies Inc, San Diego, CA, USA). The patients were evaluated to determine whether the Glasgow Coma Scale score and cerebral blood flow improved with treatment. After the initial treatment, consciousness levels as measured by the Glasgow Coma Scale improved from a pre-treatment median of 5 (range 3 to 6) to a post-treatment median of 7 (range 5 to 9) (p=0.0005 by paired Wilcoxon test); mean blood flow velocity in the middle cerebral arteries as shown by transcranial Doppler sonography increased from a median of 37.85 cm/sec (range 20.3 to 114.0) to 57.90 (32.5 to 135.0) post-treatment (p=0.022); however, there was no significant change in the pulsatility index from a median of 1.18 (range 0.61 to 1.71) to 0.85 (range 0.70 to approximately 1.79) post-treatment (p=0.13). The 8 patients received 2 to 7 (median 5.5) times of daily 6-h liver dialysis treatments. Following the completion of all liver dialysis treatments, hepatic coma was fully resolved in 4 of 8 patients (50%) Three of 8 patients (37.5%) survived to hospital discharge, whereas 5 patients did not survive due to irreversible liver function and associated complications. In conclusion, liver dialysis treatment could improve hepatic encephalopathy, but the prognosis still depended on the underlying diseases.

Adult↗

Negligible changes in piglet serum clinical indicators or organ weights due to dietary single-cell long-chain polyunsaturated oils.

Single-cell oils are currently included in human infant formula as sources of the long-chain polyunsaturates (LCP) docosahexaenoic acid (DHA) and arachidonic acid (AA) in many countries, but have not yet been approved for use in the USA. We prepared four bovine-milk-based formulas with AA/DHA=0, 34/17, 68/34 and 170/85 (mg per 100 kcal formula) provided by two commercial single-cell oils. These levels correspond approximately to 0, 1, 2 and 5 times the concentrations used in infant formulas and, due to greater consumption of formula per unit body weight, resulted in daily consumption of approximately 0, 3, 6 and 16 times those anticipated for human infants. All other dietary fat (47% of calories) was provided by a vegetable oil blend used in commercial human infant formulas. Domestic piglets were allowed to nurse with the sow for 24 h after parturition, then removed to individual cages and maintained on one of the four diets. At 30 days of age the piglets were sacrificed, and serum collected and organs weighed. With litters treated as a blocked variable, no significant differences among groups were found by analysis of variance for the following serum assays: alkaline phosphatase, alanine aminotransferase (ALT), aspartate aminotransferase (AST), blood urea nitrogen (BUN), creatinine, albumin, glucose, cholesterol, triglycerides, and total protein. No significant differences were found for hematocrit or body weight. No significant differences were found among groups for weights of liver, brain, heart, lung, spleen, kidneys or lung, analyzed as absolute weight and as a fraction of body weight. Hematoxylin/eosin liver sections examined by light microscopy showed no abnormalities as evaluated by an independent pathologist. DHA content in liver and heart and AA content in heart showed significant dose-related accumulation (P<0.05) and confirmed enhanced tissue accretion of DHA and AA from both oils. We conclude that single-cell oils in formula consumed for 1 month in amounts up to 16-fold greater than proposed for human infants in the USA did not result in clinical chemistry or histopathologic indications of toxic effects in neonatal pigs.

Animals↗

A comparative thrombogenicity study of heparin soaked fluoro-passivated polyester and ePTFE patches in sheep.

OBJECTIVES: to compare heparin soaked fluoro-passivated gelatine sealed polyester and expanded polytetrafluoroethylene (ePTFE) patches in a sheep model of acute platelet accumulation following patch angioplasty. MATERIALS AND METHODS: heparin soaked patches were placed in the carotid arteries of 9 sheep and autologous (111)Indium labelled platelets were infused. The patches were explanted two hours after the injection of labelled platelets. Median specimen radioactivity was calculated as a ratio of radioactivity in explanted and in 4 ml of blood. Explanted patches were also investigated by scanning electron microscopy (SEM). RESULTS: platelet accumulation was significantly greater on ePTFE patches. For both materials platelet accumulation was greater at the distal end compared to the proximal (p<0.05). SEM demonstrated more platelets as well as thicker thrombus layer on ePTFE-patches. CONCLUSION: in sheep carotid arteries, a fluoropassivated gelatine sealed polyester patch appears to result in less platelet accumulation when compared to ePTFE.

Animals↗

Does nifedipine prevent the tachysystole associated with misoprostol induction?

OBJECTIVE: To determine the efficacy of oral nifedipine as prophylaxis against uterine tachysystole associated with misoprostol induction of labor. METHODS: A total of 116 patients undergoing induction with term, singleton pregnancies were enrolled. All patients received 50 microg misoprostol intravaginally every 4 h. Patients were randomly assigned also to receive nifedipine 10 mg orally every 4 h, or no prophylaxis. The primary outcome variable was the incidence of 12 or more contractions in any 20-min interval. RESULTS: Data on 106 patients were available for analysis. There were 55 subjects in the misoprostol-nifedipine group and 51 controls. Nifedipine did not diminish the incidence of tachysystole when added to misoprostol (42% vs. 45% without nifedipine; p = 0.7). CONCLUSION: Prophylactic oral nifedipine was not shown to decrease the uterine tachysystole associated with vaginal misoprostol induction at a 50-microg dose.

Administration, Intravaginal↗

The applications of capture-recapture models to epidemiological data.

Capture-recapture methodology, originally developed for estimating demographic parameters of animal populations, has been applied to human populations. This tutorial reviews various closed capture-recapture models which are applicable to ascertainment data for estimating the size of a target population based on several incomplete lists of individuals. Most epidemiological approaches merging different lists and eliminating duplicate cases are likely to be biased downwards. That is, the final merged list misses those who are in the population but were not ascertained in any of the lists. If there are no matching errors, then the duplicate information collected from a capture-recapture experiment can be used to estimate the number of missed under proper assumptions. Three approaches and their associated estimation procedures are introduced: ecological models; log-linear models, and the sample coverage approach. Each approach has its unique way of incorporating two types of source dependencies: local (list) dependence and dependence due to heterogeneity. An interactive program, CARE (for capture-recapture) developed by the authors is demonstrated using four real data sets. One set of data deals with infection by the acute hepatitis A virus in an outbreak in Taiwan; the other three sets are ascertainment data on diabetes, spina bifida and infants' congenital anomaly discussed in the literature. These data sets provide examples to show the usefulness of the capture-recapture method in correcting for under-ascertainment. The limitations of the methodology and some cautionary remarks are also discussed.

Adult↗

Limb preservation by Gore-Tex vascular graft for groin recurrence after postoperative adjuvant radiation in vulvar cancer.

BACKGROUND: Recurrent vulvar cancer involving the femoral artery after groin radiation is usually considered inoperable. A patient with such recurrent vulvar cancer successfully treated by femoral vascular graft and rectus abdominis myocutaneous flap reconstruction with limb salvage is described. CASE: A 51-year-old woman had recurrent vulvar cancer involving the right femoral vessels 6 months after a radical vulvectomy plus inguinal lymphadenectomy and postoperative pelvic and groin radiation. Radical en bloc excision of tumor along with the involved femoral artery and vein followed by Gore-Tex vascular graft and rectus abdominis myocutaneous flap reconstruction led to a complete remission. However, occlusion of the grafted vessels occurred 21 months following bypass surgery. Since the compensatory collaterals were established, debridement and removal of the occluded graft were carried out. The patient has been clinically free of disease for more than 48 months since graft reconstruction surgery. CONCLUSION: It is highlighted that aggressive tumor resection with limb salvage is feasible even for patients with vulvar cancer of the groin recurrence involving the femoral artery after primary surgery and groin radiation.

Blood Vessel Prosthesis↗

Multivitamin use and colon cancer mortality in the Cancer Prevention Study II cohort (United States).

OBJECTIVE: Multivitamins contain several nutrients, including folic acid, which are hypothesized to reduce colon cancer risk. Previous epidemiologic studies have suggested that effects of multivitamins containing substantial amounts of folic acid (introduced in 1973) may not be evident until 15 or more years since first use. METHODS: We examined the association between daily multivitamin use and colon cancer mortality among 806,397 US men and women in the Cancer Prevention Study II cohort who completed a questionnaire at enrollment in 1982 and were followed for mortality through 1998. RESULTS: After multivariate adjustment, multivitamin use at enrollment showed little association with colon cancer mortality. After 15 years since first use of a multivitamin potentially containing folic acid, we observed slightly decreased risk of colon cancer mortality (rate ratio (RR) = 0.89, 95% confidence interval (CI) 0.80-0.99). Consistent with previous reports, this association was stronger among participants consuming two or more alcoholic drinks per day (RR = 0.71, 95% CI 0.56-0.91). CONCLUSION: Our results are consistent with a modest reduction in colon cancer mortality associated with use of folic acid-containing multivitamins among moderate to heavy alcohol users.

Adult↗

Application of extracorporeal membrane oxygenation in adult burn patients.

Adult respiratory distress syndrome (ARDS) has been the major cause of mortality in burn injury. The authors reported the experience of using extracorporeal membrane oxygenation (ECMO) to treat adult burn patient with ARDS. Three patients with burn or electric injury, around 48.9% of body surface area over second-degree burns, developed ARDS after resuscitation. All had positive blood culture and depended on a ventilator more than 5 days before ECMO. Venovenous (VV) ECMO was started at the beginning of severe respiratory failure with an oxygen index of 61.6 +/- 15.5 cm H2O/mm Hg (> or =40 cm H2O/mm Hg), partial arterial oxygen tension to inspired oxygen fraction (Pa(O2)/Fi(O2)) of 46.1 +/- 7.0 mm Hg (< or =200 mm Hg), positive end expiratory pressure (PEEP) of 15.7 +/- 1.6 cm H2O (> or =10 cm H2O), alveolar-arterial difference in oxygen concentration (A-a D(O2)) of 618.9 +/- 19.3 mm Hg (> or =300 mm Hg), and lung compliance of 17.3 +/- 4.6 ml/cm H2O (< or =30 ml/cm H2O). The VV type had to be converted to the newly designed veno-venoarterial (V-VA) ECMO due to the myocardial dysfunction. Two of three patients survived. The duration of ECMO was 160.2 +/- 51.1 h. Two patients received debridement of escar during ECMO support and desmopressin infusion, and no increased bleeding or coagulopathy was found. The respiratory parameters were significantly improved after ECMO, especially in the survivors. ECMO is also suitable for ARDS in adult burn injury.

Adult↗

Value of human papillomavirus deoxyribonucleic acid testing after conization in the prediction of residual disease in the subsequent hysterectomy specimen.

OBJECTIVE: Our aim was to evaluate human papillomavirus deoxyribonucleic acid testing after conization in predicting residual disease in the subsequent hysterectomy specimen. STUDY DESIGN: A prospective study was conducted on 75 patients with grade 3 cervical intraepithelial neoplasia who had cone margins or endocervical curettage specimens showing disease and who elected to undergo hysterectomy after conization. All patients underwent high-risk human papillomavirus deoxyribonucleic acid testing by the Hybrid Capture II (Digene Corporation, Gaithersburg, MD) system before conization and at the time of hysterectomy (within 2-7 weeks after conization). The presence of human papillomavirus deoxyribonucleic acid in cells obtained by endocervical brush before hysterectomy was correlated with residual disease in the hysterectomy specimens. RESULTS: Of the 92 patients enrolled, 75 were eligible. Of these 75 patients, 52 (69.3%) had persistent human papillomavirus deoxyribonucleic acid after conization, and 27 (36.0%) of the 75 patients had residual cervical neoplasia in the hysterectomy specimens. Those with negative results for human papillomavirus deoxyribonucleic acid after conization were all (23/23) without residual disease in the uterus (100% negative predictive value). All those who had residual disease (27/27) had positive results for human papillomavirus deoxyribonucleic acid at the time of hysterectomy (100% sensitivity). Postconization human papillomavirus deoxyribonucleic acid status (odds ratio, 4.000; 95% confidence interval, 1.531-10.449; P =.005) and grade of dysplasia after endocervical curettage (classified as grade 2 cervical intraepithelial neoplasia or less severe disease vs grade 3 cervical intraepithelial neoplasia: odds ratio, 6.612; 95% confidence interval, 2.837-15.409; P =.0002) were significantly associated with residual tumor in the uterus. CONCLUSIONS: This prospective study confirms an excellent sensitivity and negative predictive value of human papillomavirus deoxyribonucleic acid testing after conization in predicting residual cervical neoplasia. A strategy of managing patients with grade 3 cervical intraepithelial neoplasia, based on postconization human papillomavirus deoxyribonucleic acid findings and endocervical curettage results, is proposed.

Adult↗

Utility of routine serial computed tomography for blunt intracranial injury.

BACKGROUND: To determine the utility of routine serial head computed tomography (H-CT) for predicting need for invasive neurosurgical intervention in patients with blunt intracranial injuries (BICI). METHODS: Patients treated at a Level I trauma center with BICI over a 4-year period were reviewed. RESULTS: Of the 4,273 blunt trauma patients evaluated, 9.7% (415/4,273) were diagnosed as having BICI. Invasive intervention (craniotomy, ICP monitoring, ventriculostomy, or angiogram) was performed in 41.2% (171/415) of patients with BICI. Of these, 94.7% (162/171) had the procedure performed as a result of the initial H-CT. The remaining 5.3% (9/171) had the intervention performed as a result of a subsequent H-CT. Serial H-CT documented worsening of BICI in 32.3% (64/198) of the patients, but only those who had significant corresponding clinical deterioration had an invasive procedure as a result. CONCLUSION: In patients with an unchanged or normal neurologic exam, a routine serial H-CT did not influence subsequent invasive neurosurgical intervention.

Adolescent↗

Vitamin C and vitamin E supplement use and colorectal cancer mortality in a large American Cancer Society cohort.

Some recent epidemiological studies have suggested that use of vitamin C or vitamin E supplements, both of which are important antioxidants, may substantially reduce the risk of colon or colorectal cancer. We examined the association between colorectal cancer mortality and use of individual vitamin C and E supplements in the American Cancer Society's Cancer Prevention Study II cohort. We used proportional hazards modeling to estimate rate ratios among 711,891 men and women in the United States who completed a self-administered questionnaire at study enrollment in 1982, had no history of cancer, and were followed for mortality through 1996. During the 14 years of follow-up, 4404 deaths from colorectal cancer occurred. After adjustment for multiple colorectal cancer risk factors, regular use of vitamin C or E supplements, even long-term use, was not associated with colorectal cancer mortality. The combined-sex rate ratios were 0.89 [95% confidence interval (CI), 0.73-1.09] for 10 or more years of vitamin C use and 1.08 (95% CI, 0.85-1.38) for 10 or more years of vitamin E use. In subgroup analyses, use of vitamin C supplements for 10 or more years was associated with decreased risk of colorectal cancer mortality before age 65 years (rate ratio = 0.48; 95% CI, 0.28-0.81) and decreased risk of rectal cancer mortality at any age (rate ratio = 0.40; 95% CI, 0.20-0.80). Our results do not support a substantial effect of vitamin C or E supplement use on overall colorectal cancer mortality.

Adult↗

Body mass index, height, and prostate cancer mortality in two large cohorts of adult men in the United States.

Body weight and height have both been associated consistently with postmenopausal breast cancer but less consistently with prostate cancer. The present study examined the relationship between body mass index (BMI), height, and death from prostate cancer in two large American Cancer Society cohorts. Men in the study were selected from the male participants in Cancer Prevention Study I (CPS-I; enrolled in 1959 and followed through 1972) and Cancer Prevention Study II (CPS-II; enrolled in 1982 and followed through 1996). After exclusions, 1,590 prostate cancer deaths remained among 381,638 men in CPS-I and 3,622 deaths among 434,630 men in CPS-II. Cox proportional hazards modeling was used to compute rate ratios (RR) and to adjust for confounders. Prostate cancer mortality rates were significantly higher among obese (BMI, > or =30) than nonobese (BMI, <25) men in both cohorts [adjusted RR, 1.27; 95% confidence interval (CI), 1.04-1.56 in CPS-I; RR, 1.21; 95% CI, 1.07-1.37 in CPS-II]. Prostate cancer mortality rates in the CPS-I cohort were lowest for the shortest men (RR, 0.80; 95% CI, 0.63-1.03 for men <65 inches versus 65-66 inches) and highest for the tallest men (RR, 1.39; 95% CI, 1.11-1.74 for men > or =73 inches tall versus 65-66 inches). Rates remained constant among men 65-72 inches tall. No association between height and prostate cancer mortality was observed in the CPS-II cohort (RR, 1.03; 95% CI, 0.82-1.29 for men > or =75 versus 65-66 inches). These results support the hypothesis that obesity increases risk of prostate cancer mortality. Decreased survival among obese men may be a likely explanation for this association.

Adult↗

Rapid recovery of spontaneous baroreflex after sevoflurane anesthesia in ambulatory surgery.

BACKGROUND: Although sevoflurane seems to have fulfilled the criteria of ideal anesthetic agent for ambulatory surgery, its effects on intraoperative alteration and postoperative recovery of arterial baroreflex have not been well documented. This study assessed the time required for patients anesthetized with sevoflurane to regain their baseline baroreflex after ambulatory surgeries. METHODS: Ten ASA class I female patients scheduled for minor gynecological operation (D&C) were enrolled in this study. Spontaneous baroreflex sensitivity (SBR) calculated by sequence analysis of beat-to-beat variations in systolic arterial pressure and R-R intervals was recorded before anesthesia (Baseline), during anesthesia (Anesthesia), five min after operation (Post-op 1) and ten min after operation (Post-op 2). Data obtained from Anesthesia, Post-op 1, and Post-op 2 was compared with the Baseline. RESULTS: SBR value determined in Baseline group (28.6 +/- 4.9 ms/mmHg) was significantly different from Anesthesia group (12.2 +/- 2.1 ms/mmHg) and Post-op 1 group (15.8 +/- 1.8 ms/mmHg). Patients regained their conscious baseline baroreflex sensitivity within ten min after sevoflurane was switched off. CONCLUSIONS: Sevoflurane anesthesia depresses SBR and provides a quick SBR recovery upon emergence.

Adult↗

A prospective study of diet and stomach cancer mortality in United States men and women.

Frequent consumption of fruits, vegetables, and whole grains has been associated with a reduced risk of stomach cancer in the majority of case-control studies of these factors: however, prospective studies have been less consistent. We examined the association between selected major food groups (citrus fruits, vegetables, whole grains, and processed meats) and risk of fatal stomach cancer in the Cancer Prevention Study (CPS) II cohort of 1.2 million United States men and women. During 14 years of follow-up, we documented 439 stomach cancer deaths in women and 910 in men after exclusion of individuals with prevalent cancers, inadequate diet information, and recent weight loss at baseline in 1982. After controlling for other risk factors, none of the food groups examined were associated with risk of stomach cancer except for an unexpected increased risk with vegetable consumption in women [relative risk (RR) = 1.25; 95% confidence interval (CI), 0.99-1.58; highest versus lowest tertile, P = 0.06 for trend]. A high overall plant food intake (a sum of vegetables, citrus fruit, and whole grains) was associated with reduced risk in men (RR = 0.79; 95% CI, 0.67-0.93; highest versus lowest tertile, P = 0.003 for trend), but not in women (RR = 1.18; 95% CI, 0.93-1.50; P = 0.16 for trend). Of individual foods examined, liver consumption greater than twice/week was associated with an increased risk of fatal stomach cancer in women (RR = 1.96; 95% CI, 1.09-3.53) and men (RR = 1.63; 95% CI, 1.02-2.62) compared with nonconsumers. This study supports a modest role for plant foods in reducing the risk of fatal stomach cancer in men, but not in women.

Adult↗

Intralesional injection for hepatic metastasis from cervical carcinoma. A report of two cases.

BACKGROUND: The treatment of isolated hepatic metastasis from carcinoma of the uterine cervix has yet to be established. We tested the efficacy of percutaneous injection of ethanol and acetic acid as a curative-intent treatment modality for this rare event. CASES: Under real-time sonographic guidance, two patients with a solitary hepatic metastasis from carcinoma of the cervix were treated with 99.5% percutaneous ethanol injection (one patient) and 50% percutaneous acetic acid injection (the other patient). The treatment was repeated weekly if laboratory data permitted and aspiration cytology interpreted on site showed tumor cells. Cytology after complete treatment showed no residual tumor cells in either case. Both patients had no evidence of disease during follow-up for 12 and 24 months, respectively. CONCLUSION: Treatment was successful in two patients with isolated hepatic metastatic lesions from carcinoma of the cervix who received percutaneous injection of 99.5% ethanol or 50% acetic acid.

Acetic Acid↗

Cigarette smoking and colorectal cancer mortality in the cancer prevention study II.

BACKGROUND: Recent studies suggest that long-term cigarette smoking is associated with an increased risk of colorectal cancer. Whether the association is causal or due to confounding remains unclear. METHODS: We examined cigarette smoking in relation to colorectal cancer mortality, evaluating smoking duration and recency and controlling for potential confounders in the Cancer Prevention Study II. This prospective nationwide mortality study of 1 184 657 adults (age > or =30 years) was begun by the American Cancer Society in 1982. After exclusions, our analytic cohort included 312 332 men and 469 019 women, among whom 4432 colon or rectal cancer deaths occurred between 1982 and 1996 among individuals who were cancer free in 1982. Rate ratios (RRs) and 95% confidence intervals (CIs) were estimated by fitting Cox proportional hazards models. All statistical tests were two-sided. RESULTS: Multivariate-adjusted colorectal cancer mortality rates were highest among current smokers, were intermediate among former smokers, and were lowest in lifelong nonsmokers. The multivariate-adjusted RR (95% CI) for current compared with never smokers was 1.32 (1.16-1.49) among men and 1.41 (1.26-1.58) among women. Increased risk was evident after 20 or more years of smoking for men and women combined as compared with never smokers. Risk among current and former smokers increased with duration of smoking and average number of cigarettes smoked per day; risk in former smokers decreased significantly with years since quitting. If the multivariate-adjusted RR estimates in this study do, in fact, reflect causality, then approximately 12% of colorectal cancer deaths among both men and women in the general U.S. population in 1997 were attributable to smoking. CONCLUSIONS: Long-term cigarette smoking is associated with increased risk of colorectal cancer mortality in both men and women. Clear reduction in risk is observed with early smoking cessation.

Adolescent↗

Drosophila dumpy is a gigantic extracellular protein required to maintain tension at epidermal-cuticle attachment sites.

BACKGROUND: Growth and morphogenesis during development depend both on patterning genes, which assign positional information, and on genes that regulate mechanical forces. The dumpy gene of the fruit fly Drosophila melanogaster is an example of the latter class, with mutant phenotypes affecting size and shape of the limbs, thoracic cuticle, trachea and mouthparts. RESULTS: The genetically complex dumpy locus was found to span over 100 kb and encode a gigantic 2.5 MDa extracellular matrix protein. Dumpy represents an extreme form of modular protein evolution, containing 308 epidermal growth factor (EGF) modules, interspersed with a new module class, DPY, and terminating in a crosslinking zona pellucida domain and membrane anchor sequence. We determined the three-dimensional structure of the DPY module by nuclear magnetic resonance (NMR) spectroscopy and found that it forms a disulphide-stabilised beta sheet motif, capable of linking end-to-end with EGF modules to form a fibre. Consistent with its cuticle phenotypes, dumpy is expressed at several sites of cuticle-epidermal cell attachment, including the trachea and the muscle tendon cells, which mediate anchorage of the muscles to the cuticle. CONCLUSIONS: The dumpy gene encodes a gigantic extracellular molecule that we predict to be a membrane-anchored fibre of almost a micrometer in length. Insertion and crosslinking of this fibre within the cuticle may provide a strong anchor for the underlying tissue, allowing it to maintain mechanical tension at sites under stress. This would explain its contribution to tissue morphogenesis through its regulation of mechanical properties.

Amino Acid Sequence↗