Evaluation of three methods for detection of methicillin-resistant Staphylococcus aureus

AIM: To evaluate GenoType methicillin-resistant Staphylococcus aureus (MRSA) Direct assay and cultivation for the identification of MRSA by using mecA polymerase chain reaction (PCR) as the “gold standard” assay. METHODS: In total of 61 nasal specimens from patients at the intensive care unit were studied by GenoType MRSA Direct test, conventional culture method and automated bacterial identification system. The results of GenoType MRSA Direct assay were compared to conventional culture method the identification of MRSA and mecA gene PCR as the “gold standard” method. The sensitivity, specificity, positive predictive value and negative predictive value were calculated. RESULTS: In total, 61 specimens were studied. Fifty-four specimens (88.5%) were negative by all three methods. Six swabs (9.8%) were found positive by GenoType MRSA Direct test, conventional culture method and automated bacterial identification system. The presence of mecA in these strains was confirmed by PCR. One swab sample was negative for culture methods but MRSA and mecA gene were detected by GenoType MRSA Direct test and mecA PCR respectively. GenoType MRSA Direct test had a sensitivity of 100% (6/6) and a specificity of 100% (55/55), with a positive predictive value of 100% and a negative predictive value of 98%. Culture method of MRSA had a sensitivity of 83.3% (5/6) and a specificity of 98.2% (55/56). CONCLUSION: It was found that the GenoType MRSA Direct assay, which is a rapid and accurate test, is of the same sensitivity and specificity with mecA PCR. The GenoType MRSA Direct assay can be a better tool for rapid and accurate detection of MRSA in diagnostic laboratories.     

Factors associated with contraceptive use in Tehran,Iran

Objectives In spite of the government's efforts, the prevalence of contraceptive use in Iran is only 55.4%. Health concerns, side effects, failure of the methods and some demographic issues, among which education, age, and number of daughters, have a great influence on the enforcement of contraceptive measures. The aim of the present study was to identify factors affecting contraceptive use in Iran.

Methods Data from the project ‘The study of contraceptive practice in Tehran, 1999–2000’ were analyzed with regard to the factors associated with contraceptive use by Iranian couples. A total of 4042 women at reproductive ages who had delivered in one of the 12 teaching hospitals of Tehran and had at least one child that lived for at least 24 hours after birth, were interviewed using a questionnaire that gathered information about their socio-demographic status, fertility history, and other characteristics.

Results Using a multinomial logistic regression, it was found that the woman's age, her own or her husband's level of education, previous awareness about contraceptive methods, number of abortions, and number of sons and daughters were factors that were significantly associated with contraceptive use.

Conclusions A number of factors affect the application of contraceptive measures. It is essential that health policy makers be aware of these to promote contraception and population control.     

Directed glia‐assisted angiogenesis in a mature neurosensory structure: Pericytes mediate an adaptive response in human dental pulp that maintains blood‐barrier function

The specialized tightly controlled microcirculation of craniofacial neurosensory organs is an essential evolutionary adaptation and yet a dilemma where angiogenic remodeling occurs. Despite extreme plasticity of neurosensory structures, the capacity to reconcile barrier phenotype of the microcirculation with an angiogenic cascade is not known. Here we provide primary evidence for such a response in an elemental neurosensory structure, human dental pulp, following chronic carious insult. In response to hypoxic challenge neurosensory odontoblasts express hypoxia‐inducible factor‐1α and notch‐1. Associated radial rearrangement of astrocyte‐like telacytes that communicate through a cell‐poor zone with the microvasculature is observed. Activated pericytes characterized by expression of α‐smooth muscle actin are located adjacent to the telacyte attachment to the vasculature. In this location, endothelial expression of sonic hedgehog parallels expression of notch‐1 by pericytes. The angiogenic response is initiated by pericyte contraction and altered endothelial polarity and proliferation leading to intussusception of endothelial cells and extensive remodeling of basement membrane with upregulation of laminin‐8 and laminin‐5. These responses guide intravascular loop formation that maintains both intact basement membrane and tight junctions. This initial phase is followed by formation of anastomoses that enhance the hemodynamic capacity of the intravascular loops. The formation of anastomoses is mediated by extension of cytonemes from pericytes guided by MHC‐II⁺/CD‐163⁺ microglia aligned with the telacytes. The cytonemes seek out pericytes on adjacent intravascular loops to initiate migration of endothelial cells. These findings support a new paradigm for understanding angiogenic capacity of neurosensory structures and aberrations of this response manifest as neurovasculopathies. J. Comp. Neurol. 520:3803–3826, 2012. © 2012 Wiley Periodicals, Inc.     

Becker's naevus and segmental naevus depigmentosus: An example of twin spotting?

A 12-year-old girl presented with a 1-year history of a Becker's naevus involving the right posterior thigh and gluteal area. In addition, three hypopigmented macules of naevus depigmentosus distributed in a segmental pattern on the medial aspect of the right posterior thigh had been present since birth. We suggest that their unusual coexistence in close proximity may represent an example of twin spotting.     

The fragility of statistically significant results in otolaryngology randomized trials

Objectives

The American Academy of Otolaryngology–Head and Neck Surgery regards randomized controlled trials as class A evidence. A novel method to determine the robustness of outcomes in trials is the fragility index. This index represents the number of patients whose status would have to change from a non-event to an event to make a statistically significant result non-significant.