A human mitochondrial DNA standard reference material for quality control in forensic identification, medical diagnosis, and mutation detection

A human mitochondrial DNA (mtDNA) standard reference material (SRM 2392) will provide quality control when mtDNA is sequenced for forensic identifications, medical diagnosis, or mutation detection. SRM 2392 includes DNA from two lymphoblast cell cultures (CHR and 9947A) and cloned DNA from the CHR HV1 region, which contains a C stretch and is difficult to sequence. The mtDNA sequence (but not the DNA) of a third human template GM03798 is provided for comparison. Fifty-eight unique primer sets allow any area or the entire mtDNA (16,569 bp) to be amplified and sequenced. While none of the differences in these three templates correspond to published mutations associated with specific diseases, some of these differences did result in animo acid changes compared with that published by S. Anderson et al. (1981, Nature 290: 457-465). An interlaboratory evaluation of the amplification, sequencing, and data analysis of the CHR template was conducted by four laboratories. Corroboration of the SRM results will provide quality assurance that any unknown mtDNA is also being amplified and sequenced correctly.     

Surgical options in the management of groin hernias

Extracellular Yersinia adhering at the surface of a eukaryotic cell translocate effector Yops across the plasma membrane of the cell by a mechanism requiring YopD and YopB, the latter probably mediating pore formation. We studied the role of SycD, the intrabacterial chaperone of YopD. By producing GST-YopB hybrid proteins and SycD in Escherichia coli, we observed that SycD also binds specifically to YopB and that this binding reduces the toxicity of GST-YopB in E. coli. By analysis of a series of truncated GST-YopB proteins, we observed that SycD does not bind to a discrete segment of YopB. Using the same approach, we observed that YopD can also bind to YopB. Binding between YopB and YopD occurred even in the presence of SycD, and a complex composed of these three proteins could be immunoprecipitated from the cytoplasm of Yersinia. In a sycD mutant, the intracellular pool of YopB and YopD was greatly reduced unless the lcrV gene was also deleted. As LcrV is known to interact with YopB and YopD and to promote their secretion, we speculate that SycD prevents a premature association between YopB-YopD and LcrV.     

Knowledge, economy, technology and society: The politics of discourse

The WSIS is centrally interested in knowledge and has defined for itself a mission that is broadly humanitarian. Its development ‘talk’ is, rightly, replete with notions of equity, preserving culture, justice, human rights and so on. In incorporating such issues into knowledge society and economy discussions, WSIS has adopted a different posture towards knowledge than is seen in dominant discourses. This study analyses the dominant knowledge discourse using a large corpus of knowledge-related policy documents, discourse theory and an interrelational understanding of knowledge. I show that it is important to understand this dominant knowledge discourse because of its capacity to limit thought and action in relation to its central topic, knowledge. The results of this study demonstrate that the dominant knowledge discourse is technocratic, frequently insensitive to the humane mission at the core of the WSIS, and is based on a partial understanding of what knowledge is and how knowledge systems work. Moreover, I show that knowledge is inherently political, that the dominant knowledge discourse is politically oriented towards the concerns of business and technology, but that an emancipatory politics of knowledge is possible.     

The psychosocial impact of Hurricane Katrina on persons with disabilities and independent living center staff living on the American Gulf Coast.

Objectives: To determine the impact of Hurricane Katrina on the psychosocial health of people with disabilities and on the ability of people with disabilities in the affected area to live independently. Participants: Transcribed conversations were analyzed for 56 survivors of Hurricane Katrina on the American Gulf Coast, all of whom were persons with disabilities or persons working with them. Method: Semi-structured interviews were conducted either individually or in focus groups with participants. Qualitative analysis was undertaken using hermeneutic techniques. Results: Six major themes emerged: faith, incredulousness, blaming others or oneself, family adaptation and resiliency, and work and professional responsibility. Conclusions: The resiliency of persons with disabilities to adapt to disasters can be better understood through factors such as these, providing an effective barometer of social capital that can help societies prepare for future disasters among those most vulnerable. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Pyrotechnic and Thermal Studies on the Magnesium‐Strontium Nitrate Pyrotechnic System

The pyrotechnic and thermal properties of a range of binary magnesium‐strontium nitrate compositions containing from 10% to 90% by mass of magnesium have been determined. The burning rate and light output were measured after consolidating the compositions into cardboard tubes. The exothermicity, temperature of ignition and time to ignition of the compositions were also determined and the products of combustion were characterized.     

Racial and ethnic disparities in self-assessed health status: evidence from the National Survey of Families and Households

We examined racial and ethnic disparities in global health assessment and functional limitations of daily activities among whites, blacks and Hispanics, and within the Hispanic origin among Mexicans, Puerto Ricans, Cubans, and 'Others'. Logistic regression were employed to estimate the log odds of reporting 'poor health' and 'having functional limitations' among 12,814 respondents from the 1987-1988 National Survey of Families and Households. Compared with whites, blacks had an increased risk of reporting poor health and functional limitations. Hispanics had even a higher risk of reporting poor health, but did not have an increased risk of reporting functional limitations. Among Hispanics, Mexicans were more likely than whites to report poor health, whereas Puerto Ricans were more likely than whites to experience functional limitations. Both race and ethnicity remain important factors in explaining the disparities in self-assessed health status independent of socioeconomic status (SES). Meanwhile, the way self-assessed health status varies with ethnicity is importantly stratified by SES as measured by income and education. These results suggest that future research should analyze the interplay between ethnicity and SES rather than assuming measuring either captures all the important variation.     

The mutation T315A in Candida albicans sterol 14alpha-demethylase causes reduced enzyme activity and fluconazole resistance through reduced affinity

Sterol 14alpha-demethylase (P45051) is the target for azole antifungal compounds, and resistance to these drugs and agrochemicals is of significant practical importance. We undertook site-directed mutagenesis of the Candida albicans P45051 heterologously expressed in Saccharomyces cerevisiae to probe a model structure for the enzyme. The change T315A reduced enzyme activity 2-fold as predicted for the removal of the residue that formed a hydrogen bond with the 3-OH of the sterol substrate and helped to locate it in the active site. This alteration perturbed the heme environment, causing an altered reduced carbon monoxide difference spectrum with a maximum at 445 nm. The changes also reduced the affinity of the enzyme for the azole antifungals ketoconazole and fluconazole and after expression induced by galactose caused 4-5-fold azole resistance in transformants of S. cerevisiae. This is the first example of a single base change in the target enzyme conferring resistance to azoles through reduced azole affinity.