Cultural and contextual influences in mental health help seeking: A focus on ethnic minority youth.

In this article, a mental health help-seeking model is offered as a framework for understanding cultural and contextual factors that affect ethnic minority adolescents' pathways into mental health services. The effects of culture and context are profound across the entire help-seeking pathway, from problem identification to choice of treatment providers. The authors argue that an understanding of these help-seeking pathways provides insights into ethnic group differences in mental health care utilization and that further research in this area is needed, (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Crystal structure of cis-biphenyl-2,3-dihydrodiol-2,3-dehydrogenase from a PCB degrader at 2.0 A resolution

cis-Biphenyl-2,3-dihydrodiol-2,3-dehydrogenase (BphB) is involved in the aerobic biodegradation of polychlorinated biphenyls (PCBs). The crystal structure of the NAD+-enzyme complex was determined by molecular replacement and refined to an R-value of 17.9% at 2.0 A. As a member of the short-chain alcohol dehydrogenase/reductase (SDR) family, the overall protein fold and positioning of the catalytic triad in BphB are very similar to those observed in other SDR enzymes, although small differences occur in the cofactor binding site. Modeling studies indicate that the substrate is bound in a deep hydrophobic cleft close to the nicotinamide moiety of the NAD+ cofactor. These studies further suggest that Asn143 is a key determinant of substrate specificity. A two-step reaction mechanism is proposed for cis-dihydrodiol dehydrogenases.     

Stress analysis and design optimization of a wafer-level CSP by FEM simulations and experiments

A design assessment and optimization process for wafer-level chip size packages (WLCSP) is demonstrated. Besides the basic design, the thermal stress in WLCSPs with underfill and with increased standoff height, respectively, are analyzed by finite element method (FEM) simulations. The results are validated and a lifetime model is calibrated by experiments. Also, a WLCSP with stacked balls is optimized using the FEM models. Its total gain in lifetime over the basic design is estimated to reach 780%. WLCSP with optimum underfill endure 10 to 20 times longer than the basic WLCSPs. Soft underfill, however, has almost no effect on the critical inelastic strain. In addition to these practical results, the paper discusses some of the risks of FEM models (such as the singularity problem) and proposes ways of avoiding or overcoming them.     

Structural basis for the interaction of Ras with RalGDS

The Malthus-AT system provided a satisfactory method for examining the effects of permeabilizing agents on the activity of sub-inhibitory concentrations of antibacterial agents against Pseudomonas aeruginosa G48. Under this system, disodium edetate potentiated the activity of chlorhexidine diacetate (CHA), cetylpyridinium chloride, para-chlorometaxylenol and triclosan. Nitrilotriacetic acid enhanced the activity of some of the antibacterials tested, whereas sodium polyphosphate markedly reduced the efficacy of CHA.     

Statistical approaches to determine analytical variability and specifications: application of experimental design and variance component analysis

Assessment of analytical variability is recognized as an important factor for the establishment of specifications. Estimation of the variance for an analytical procedure can be accomplished using a variety of approaches. The approach of variance component analysis was applied retrospectively, as well as prospectively, to estimate analytical variance. The prospective approach also included the use of experimental design. Recent new drug substance examples illustrating these approaches are presented. In these examples, the analytical property of potency was evaluated. Factors examined in the experimental design include laboratory, day, analyst, instrument and column. Process variability can also be determined by variance component analysis. For a stable drug substance, combining the analytical and process variances provides an estimate on the total variance for the analytical property of potency. With the total variability statistically derived, an appropriate specification that is consistent with process and analytical capability can be established.     

Optimized electrostatic surfaces parallel increased thermostability: a structural bioinformatic analysis

It has been known for some time that thermophilic proteins generallyhave increased numbers of non-covalent interactions (salt bridges,hydrogen bonds, etc.) compared with their mesophilic orthologs.Recently, anecdotal structural comparisons suggest that non-specificacid–base ion pairs on the protein surface can be an evolutionaryefficient mechanism to increase thermostability. In this comprehensivestructural analysis, we confirm this to be the case. Comparisonof 127 orthologous mesophilic– thermophilic protein groupsindicates a clear preference for stabilizing acid–basepairs on the surface of thermophilic proteins. Compared withpositions in the core, stabilizing surface mutations are lesslikely to disrupt the tertiary structure, and thus more likelyto be evolutionarily selected. Therefore, we believe that ourresults, in addition to being theoretically interesting, willfacilitate identification of charge-altering mutations likelyto increase the stability of a particular protein structure. Received July 23, 2003; revised October 14, 2003; accepted October 21, 2003     

Modeling Memory Decline in Older Adults: The Importance of Preclinical Dementia, Attrition, and Chronological Age.

This longitudinal study examined memory loss in a sample of 391 initially nondemented older adults. Analyses decomposed observed memory loss into decline associated with preclinical dementia, study attrition, terminal decline, and chronological age. Measuring memory as a function of only chronological age failed to provide an adequate representation of cognitive change. Disease progression accounted for virtually all of the memory loss in the 25% of the sample that developed diagnosable dementia. In the remainder of the sample, both chronological age and study attrition contributed to observed memory loss. These results suggest that much of memory loss in aging adults may be attributable to the progression of preclinical dementia and other nonnormative aging processes that are not captured by chronological age. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The combined free partial vastus lateralis with anterolateral thigh perforator flap reconstruction of extensive composite defects

Myocutaneous (MC) free flaps are useful for many reconstructive indications. Perforator flaps have become standard of care. The anterolateral thigh flap (ALT) donor site is popular. With the ALT flap varying sizes of vastus lateralis (VL) muscle can be harvested as a MC flap. The skin islands of these flaps have a great range of freedom when dissected on their perforator. It was hypothesised that the VL–ALT perforator flap would offer adequate tissue volume combining maximal freedom in planning with minimal donor site morbidity. From November 2001 to February 2003 a free partial VL with ALT perforator flap was used in 11 patients to reconstruct large defects. Indications for adding a muscular component were exposed bone, skull base, (artificial) dura, or osteosynthesis material, open sinuses, and lack of muscular bulk. Flaps were planned as standard ALT flaps, after which three types of dissection were performed: I. true MC flap; II. muscle flap with a skin island on one perforator, which could be rotated up to 180°; III. chimera skin perforator flap with muscle being harvested on a separate branch from the source vessel or on a side branch of the skin perforator. Mean skin size of the MC-ALT flaps was 131 cm². Mean muscle part size of the MC-ALT flaps was 268 cm³. Muscular parts were custom designed for all defects. No total or partial flap failures were seen. Colour mismatch was seen in 6 of 8 patients, when skin was used in the facial area in this all white population. Excessive flap bulk was found in 8 of 11 patients at 6 weeks, however, only in 2 of 11 patients after 6 months. Patients were satisfied with the functional result (8 of 11 patients) as well as the cosmetic result of their reconstruction (7 of 11 patients). All less satisfied patients had received their flap for external facial skin reconstruction. Donor site morbidity was minimal. The combined free partial VL with ALT perforator flap proved valuable as a (chimera type) MC flap with maximal freedom of planning to meet specific reconstructive demands and minimal donor site morbidity.