University at Buffalo

About: University at Buffalo is a education organization based out in Buffalo, New York, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 33773 authors who have published 63840 publications receiving 2278954 citations. The organization is also known as: UB & State University of New York at Buffalo.

Femtosecond structural dynamics drives the trans/cis isomerization in photoactive yellow protein.

Abstract: A variety of organisms have evolved mechanisms to detect and respond to light, in which the response is mediated by protein structural changes after photon absorption. The initial step is often the photoisomerization of a conjugated chromophore. Isomerization occurs on ultrafast time scales and is substantially influenced by the chromophore environment. Here we identify structural changes associated with the earliest steps in the trans-to-cis isomerization of the chromophore in photoactive yellow protein. Femtosecond hard x-ray pulses emitted by the Linac Coherent Light Source were used to conduct time-resolved serial femtosecond crystallography on photoactive yellow protein microcrystals over a time range from 100 femtoseconds to 3 picoseconds to determine the structural dynamics of the photoisomerization reaction.

High blood alcohol levels in women

Abstract: After consuming comparable amounts of ethanol, women have higher blood ethanol concentrations than men, even with allowance for differences in size, and are more susceptible to alcoholic liver disease. Recently, we documented significant "first-pass metabolism" of ethanol due to its oxidation by gastric tissue. We report a study of the possible contribution of this metabolism to the sex-related difference in blood alcohol concentrations in 20 men and 23 women. Six in each group were alcoholics. The first-pass metabolism was determined on the basis of the difference in areas under the curves of blood alcohol concentrations after intravenous and oral administration of ethanol (0.3 g per kilogram of body weight). Alcohol dehydrogenase activity was also measured in endoscopic gastric biopsies. In nonalcoholic subjects, the first-pass metabolism and gastric alcohol dehydrogenase activity of the women were 23 and 59 percent, respectively, of those in the men, and there was a significant correlation (rs...

Offline signature verification and identification using distance statistics

Abstract: This paper describes a novel approach for signature verification and identification in an offline environment based on a quasi-multiresolution technique using GSC (Gradient, Structural and Concavity) features for feature extraction. These features when used at the word level, instead of the character level, yield promising results with accuracies as high as 78% and 93% for verification and identification, respectively. This method was successfully employed in our previous theory of individuality of handwriting developed at CEDAR — based on obtaining within and between writer statistical distance distributions. In this paper, exploring signature verification and identification as offline handwriting verification and identification tasks respectively, we depict a mapping from the handwriting domain to the signature domain.

Conjugated equine oestrogen and breast cancer incidence and mortality in postmenopausal women with hysterectomy: extended follow-up of the Women's Health Initiative randomised placebo-controlled trial.

Abstract: Summary Background By contrast with many observational studies, women in the Women's Health Initiative (WHI) trial who were randomly allocated to receive oestrogen alone had a lower incidence of invasive breast cancer than did those who received placebo. We aimed to assess the influence of oestrogen use on longer term breast cancer incidence and mortality in extended follow-up of this cohort. Methods Between 1993 and 1998, the WHI enrolled 10 739 postmenopausal women from 40 US clinical centres into a randomised, double-masked, placebo-controlled trial. Women aged 50–79 years who had undergone hysterectomy and had expected 3-year survival and mammography clearance were randomly allocated by a computerised, permuted block algorithm, stratified by age group and centre, to receive oral conjugated equine oestrogen (0·625 mg per day; n=5310) or matched placebo (n=5429). The trial intervention was terminated early on Feb 29, 2004, because of an adverse effect on stroke. Follow-up continued until planned termination (March 31, 2005). Consent was sought for extended surveillance from the 9786 living participants in active follow-up, of whom 7645 agreed. Using data from this extended follow-up (to Aug 14, 2009), we assessed long-term effects of oestrogen use on invasive breast cancer incidence, tumour characteristics, and mortality. We used Cox regression models to estimate hazard ratios (HRs) in the intention-to-treat population. This study is registered with ClinicalTrials.gov, number NCT00000611. Findings After a median follow-up of 11·8 years (IQR 9·1–12·9), the use of oestrogen for a median of 5·9 years (2·5–7·3) was associated with lower incidence of invasive breast cancer (151 cases, 0·27% per year) compared with placebo (199 cases, 0·35% per year; HR 0·77, 95% CI 0·62–0·95; p=0·02) with no difference (p=0·76) between intervention phase (0·79, 0·61–1·02) and post-intervention phase effects (0·75, 0·51–1·09). In subgroup analyses, we noted breast cancer risk reduction with oestrogen use was concentrated in women without benign breast disease (p=0·01) or a family history of breast cancer (p=0·02). In the oestrogen group, fewer women died from breast cancer (six deaths, 0·009% per year) compared with controls (16 deaths, 0·024% per year; HR 0·37, 95% CI 0·13–0·91; p=0·03). Fewer women in the oestrogen group died from any cause after a breast cancer diagnosis (30 deaths, 0·046% per year) than did controls (50 deaths, 0·076%; HR 0·62, 95% CI 0·39–0·97; p=0·04). Interpretation Our findings provide reassurance for women with hysterectomy seeking relief of climacteric symptoms in terms of the effects of oestrogen use for about 5 years on breast cancer incidence and mortality. However, our data do not support use of oestrogen for breast cancer risk reduction because any noted benefit probably does not apply to populations at increased risk of such cancer. Funding US National Heart, Lung, and Blood Institute; Wyeth.

The Results of Clinical Trials in Stroke Rehabilitation Research

Abstract: • Research Problem and Methods. —There are currently 1.5 million stroke survivors in the United States. More than half of these individuals have significant residual physical disability and functional impairment. Survivors of stroke constitute the largest group of patients receiving rehabilitation services in this country. We examined existing clinical trials investigating the effectiveness of stroke rehabilitation programs to improve functional outcomes and discharge destination. One hundred twenty-four research reports were initially identified. From this sample, 36 trials meeting selected criteria were evaluated by the methods of meta-analysis. Results. —A total of 3717 patients participated in the 36 clinical trials included in the meta-analysis. The results revealed a mean d-index of 0.40±0.33. This effect size index was converted to a U 3 value of 65.5, indicating that the average patient receiving a program of focused stroke rehabilitation performed better than approximately 65.5% of those patients in comparison groups (95% confidence interval, 63.6% to 67.3%). The results also revealed a significant interaction between type of research design and method of recording the outcome of a clinical trial. Blind recording of the outcome measure appears to be an essential design characteristic in clinical trials that do not randomize patients to conditions. Conclusions. —Programs of focused stroke rehabilitation may improve functional performance for some patients who have experienced a stroke. The improvement in performance appears related to early initiation of treatment, but not to the duration of intervention. Improvements are also associated with the patient's age and the type of design. Research design should be considered an important moderator variable in planning and interpreting future clinical trials of treatment effectiveness in stroke rehabilitation.