Detection of aneuploidies in spontaneous abortions by quantitative fluorescent PCR with short tandem repeat markers: a retrospective study.

Approximately 10-15% of all pregnancies end in spontaneous abortions. Many factors can lead to embryonic loss; however, it has been well established that over 50% of all miscarriages result from chromosomal abnormalities, primarily aneuploidies (>96%). Identifying the cause of miscarriage can significantly reduce the psychological stress in women, and enable better genetic counseling for a future pregnancy. Quantitative fluorescent polymerase chain reaction (QF-PCR) has been previously used in the study of chromosomal abnormalities. In this retrospective study, the frequency of aneuploidy in samples of 130 miscarriages undergone by patients (age average: 34.1 ± 4.6 years) at our institution was determined by QF-PCR using short tandem repeat markers. The gender of the miscarriage cases was determined by amplifying the amelogenin locus (70 males and 60 females). Seventy-one of these cases (54.6%) presented aneuploidies such as trisomy, monosomy, triploidy, and double trisomy. Trisomy 22 was the most common aneuploidy (present in 14 cases), followed by trisomy 15, trisomy 16, and monosomy X. We also observed monosomy at chromosomes X and 21 and a case with multiple aneuploidies at chromosomes 16 and 22. The most common aneuploidies associated with miscarriages were detected by QF-PCR; therefore, we concluded that QF-PCR is a rapid and reliable method for the detection of aneuploidy, and can be used as an accessory to the widely used karyotype analysis.

Southern Brazil HIV type 1 C expansion into the state of São Paulo, Brazil.

Abstract HIV diversity reflects multifactorial evolutionary forces, but monitoring subtype prevalence may provide clues to understanding the epidemic. In the Americas HIV-1 C is present at significant levels only in the southern states of Brazil. We describe in this study the presence of the HIV-1 C pol genome in 11.6% (95 CI 6-21%) of antiretroviral-naive individuals from São Paulo, the major city of South America, and 6.8% (95 CI 4-12%) from the second metropolitan area of the State of São Paulo, Brazil. Moreover, a significant growth trend of this subtype was documented among cases failing therapy in the area. Sequences were obtained by direct nested PCR from cDNA retrotranscribed from plasma RNA. Phylogenetic and amino acid signatures support an expansion from variants previously identified in southern Brazil. The evaluation of additional genomic regions (partial gag, envelope, and/or integrase) in samples with HIV-1 C at pol showed extensive recombination with clade B, observed in 47% of ARV-naive cases. The spread of HIV-1 C locally and to other areas of South America should be monitored as it may influence the dynamics of the epidemic.

[Stress tests in old age. The choice of the stress protocol]. / Provas de esforço na terceira idade. Escolha do protocolo de esforço.

OBJECTIVE: To evaluate, in an elderly Portuguese population, the diagnostic capacities of the most popular treadmill stress test protocols. DESIGN: Retrospective study of an elderly Portuguese population submitted to a stress test. PATIENTS AND METHODS: A population of 45 patients (35 male), aged 65 or more years, consecutively submitted to a stress test. The average age of the group was 67.8 +/- 2.9 years. The three protocols (Bruce, Bruce Modified and Naughton) were comparatively studied in terms of the patients capacity to execute the protocol, capacity to obtain a maximum and a diagnostic stress test, and the complications of the stress test protocol. MAIN RESULTS: The Bruce protocol was used in 19 patients, the Bruce Modified in 13 patients and the Naughton protocol in 13 patients. The three protocols did not lead to any complication. The Bruce protocol led to a larger increment in heart rate (p < 0.001) and to larger maximum rate pressure product (p < 0.05) than the Naughton one. The Bruce protocol obtained a larger number of diagnostic tests (p < 0.01) and a significantly lower number of inconclusive stress tests. The Naughton protocol led to a larger duration of the exercise tests and was not suitable for some of the elderly patients owing to the exhaustion of the protocol. The results obtained with the Bruce Modified protocol were among those of other two protocols. CONCLUSIONS: In the elderly, the stress tests are safe and useful in the diagnosis of exercise induced ischemia and in the stratification of cardiovascular risk. From the protocols studied, the Bruce protocol was the most adequate, globally speaking, for this group of patients. The Bruce protocol presented a better diagnostic capacity with no complications related to the protocol.

Is the thymus a target organ in infectious diseases?

The thymus is a central lymphoid organ, in which T cell precursors differentiate and generate most of the so-called T cell repertoire. Along with a variety of acute infectious diseases, we and others determined important changes in both microenvironmental and lymphoid compartments of the organ. For example, one major and common feature observed in acute viral, bacterial and parasitic diseases, is a depletion of cortical thymocytes, mostly those bearing the CD4-CD8 double positive phenotype. This occurs simultaneously to the relative enrichment in medullary CD4 or CD8 single positive cells, expressing high densities of the CD3 complex. Additionally we noticed a variety of changes in the thymic microenvironment (and particularly its epithelial component), comprising abnormal location of thymic epithelial cell subsets as well has a denser Ia-bearing cellular network. Moreover, the extracellular matrix network was altered with an intralobular increase of basement membrane proteins that positively correlated with the degree of thymocyte death. Lastly, anti-thymic cell antibodies were detected in both human and animal models of infectious diseases, and in some of them a phenomenon of molecular mimicry could be evidenced. Taken together, the data reviewed herein clearly show that the thymus should be regarded as a target in infectious diseases.