Design and Evaluation of a Human Immunodeficiency Virus Type 1 RNA Assay Using Nucleic Acid Sequence-Based Amplification Technology Able To Quantify Both Group M and O Viruses by Using the Long Terminal Repeat as Target

Currently available human immunodeficiency virus type 1 (HIV-1) RNA quantification assays can detect most viruses of the group M subtypes, but a substantial number are missed or not quantified reliably. Viruses of HIV-1 group O cannot be detected by any commercially available assay. We developed and evaluated a quantitative assay based on nucleic acid sequence-based amplification (NASBA) technology, with primers and probes located in the conserved long terminal repeat (LTR) region of the HIV-1 genome. In 68 of 72 serum samples from individuals infected with HIV-1 subtypes A to H of group M, viruses could be detected and quantified. In serum samples from two patients infected with HIV-1 group O viruses, these viruses as well could be detected and quantified. In contrast, the currently used gag-based assay underestimated the presence of subtype A viruses and could not detect subtype G and group O viruses. The discrepancy between the results of the two assays may be explained by the number of mismatches found within and among the probe and primer regions of the subtype isolates. These data indicate that LTR-based assays, including the NASBA format chosen here, are better suited to monitoring HIV-1 therapy than are gag-based assays in an era in which multiple HIV-1 subtypes and groups are spreading worldwide.     

Simple Strategy for Direct Identification of Medically Important Yeast Species from Positive Blood Culture Vials

We compared direct inoculation of the Auxacolor yeast identification system from positive blood culture vials to standard identification with the API 20C AUX (API 20C), using 44 prospectively collected clinical specimens and 25 seeded blood culture vials. Direct inoculation of the Auxacolor system was accurate and more rapid than standard identification with the API 20C.     

Somatic Alterations Contributing to Metastasis of a Castration‐Resistant Prostate Cancer

Metastatic castration‐resistant prostate cancer (mCRPC) is a lethal disease, and molecular markers that differentiate indolent from aggressive subtypes are needed. We sequenced the exomes of five metastatic tumors and healthy kidney tissue from an index case with mCRPC to identify lesions associated with disease progression and metastasis. An Ashkenazi Jewish (AJ) germline founder mutation, del185AG in BRCA1, was observed and AJ ancestry was confirmed. Sixty‐two somatic variants altered proteins in tumors, including cancer‐associated genes, TMPRSS2‐ERG, PBRM1, and TET2. The majority (n = 53) of somatic variants were present in all metastases and only a subset (n = 31) was observed in the primary tumor. Integrating tumor next‐generation sequencing and DNA copy number showed somatic loss of BRCA1 and TMPRSS2‐ERG. We sequenced 19 genes with deleterious mutations in the index case in additional mCRPC samples and detected a frameshift, two somatic missense alterations, tumor loss of heterozygosity, and combinations of germline missense SNPs in TET2. In summary, genetic analysis of metastases from an index case permitted us to infer a chronology for the clonal spread of disease based on sequential accrual of somatic lesions. The role of TET2 in mCRPC deserves additional analysis and may define a subset of metastatic disease.     

State of the art: using natriuretic peptide levels in clinical practice

Natriuretic peptide (NP) levels (B-type natriuretic peptide (BNP) and N-terminal proBNP) are now widely used in clinical practice and cardiovascular research throughout the world and have been incorporated into most national and international cardiovascular guidelines for heart failure. The role of NP levels in state-of-the-art clinical practice is evolving rapidly. This paper reviews and highlights ten key messages to clinicians:     

HLA haplotype study of 53 juvenile insulin-dependent diabetic (I.D.D.) families

Fifty-three families with at least one IDD patient were genotyped for 5 markers of the HLA complex including Bf and DR. In 8 families one of the parents was also affected and in 12 families more than two children were diseased. In total, 76 patients were genotyped. Their haplotypes were compared with those of 106 unrelated controls (the parents of 53 genotyped families).

• 1) 

  Three haplotypes or segments of them (A2, Cw3, B15, BfS, DR4; Aw30, Cw5, B18, BfF I, DR3; and Al, Cw7, B8, BfS, DR3) were found more frequently in IDD patients.
• 2) 

  Measured by the 6 formula, the association of the postulated IDD susceptibility gene was very strong with the D-end of two of these haplotypes: BfF1, DR3 and BfS, DR4. However, the association was weak with the DR3 of the haplotype Al, Cw7, B8, BfS, DR3.
• 3) 

  An excess of HLA-identical affected siblings was found.
• 4) 

  An excess of DR3/DR4 heterozygotes was observed. By contrast, the observed frequency of patients homozygous for DR3 or DR4 was not increased, but even slightly decreased.

The data support a model of inheritance comprising at least two closely linked specifically "diabetic" loci (most of the time marked by B18, BfFl, DR3 and B15, BfS, DR4) and a non-specifically "diabetic" haplotype favouring auto-immunisation (most of the time marked by B8, BfS, DR3). This model is discussed in the light of the presented data and of those of the literature.     

Effect of limited access to sucrose on overeating and patterns of feeding

Four groups of adult rats, housed on a 12-12, light-dark cycle, were allowed access to a nutritionally complete diet and water. Three of these groups were also offered a 32% solution of sucrose. The sucrose was available for either the 24-hour period, the 12 hours of light or the 12 hours of dark. Access to sucrose led to overeating and excessive weight gain. These effects were more pronounced when the sucrose was available for the 24-hour period or during the dark. Limited access to sucrose produced a reversal of the rat's usual circadian pattern of feeding when the sucrose was available during the light and increased the rat's nocturnal hyperphagia when it was available during the dark. Sucrose intake and the proportion of calories taken from sucrose were higher in the 24-hour access group and the dark access group than the light access group. Access to sucrose did not induce a pattern of dietary selection that compromised growth or health. It appears that access to a palatable carbohydrate solution can lead to overeating and major changes in the circadian organization of feeding behavior. These data emphasize the potent role that external factors can play in the control of ingestive behavior.