Methicillin-Resistant Staphylococcus aureus: Comparison of Susceptibility Testing Methods and Analysis of mecA-Positive Susceptible Strains

Methicillin-resistant Staphylococcus aureus (MRSA) is responsible for an increasing number of serious nosocomial and community-acquired infections. Phenotypic heterogeneous drug resistance (heteroresistance) to antistaphylococcal beta-lactams affects the results of susceptibility testing. The present study compared the MRSA-Screen latex agglutination test (Denka Seiken Co., Ltd., Tokyo, Japan) for detection of PBP 2a with agar dilution, the VITEK-1 and VITEK-2 systems (bioMérieux, St. Louis, Mo.), and the oxacillin agar screen test for detection of MRSA, with PCR for the mecA gene used as the "gold standard" assay. Analysis of 107 methicillin-susceptible S. aureus (MSSA) isolates and 203 MRSA isolates revealed that the MRSA-Screen latex agglutination test is superior to any single phenotype-based susceptibility testing method, with a sensitivity of 100% and a specificity of 99.1%. Only one isolate that lacked mecA was weakly positive by the MRSA-Screen latex agglutination test. This isolate was phenotypically susceptible to oxacillin and did not contain the mecA gene by Southern blot hybridization. The oxacillin agar screen test, the VITEK-1 system, the VITEK-2 system, and agar dilution showed sensitivities of 99.0, 99.0, 99.5, and 99%, respectively, and specificities of 98.1, 100, 97.2, and 100%, respectively. The differences in sensitivity or specificity were not statistically significant. Oxacillin bactericidal assays showed that mecA- and PBP 2a-positive S. aureus isolates that are susceptible to antistaphylococcal beta-lactams by conventional methods are functionally resistant to oxacillin. We conclude that the accuracy of the MRSA-Screen latex agglutination method for detection of PBP 2a approaches the accuracy of PCR and is more accurate than any susceptibility testing method used alone for the detection of MRSA.     

Mucosal bromodomain-containing protein 4 mediates aeroallergen-induced inflammation and remodeling

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Value of papanicolaou smear in detection of Chlamydia trachomatis infection

This study was undertaken to assess the value of Papanicolaou smear for the diagnosis of Chlamydia trachomatis infection. The study was both retrospective (groups I and II) and prospective (group III). Group I consisted of 41 smears with cytomorphological changes proposed by Gupta, Kiviat, or Shiina. Group II was a control group, consisting of 30 cytologically normal smears. All these smears were subjected to specific immunofluorescent (IF) staining under identical conditions to confirm the diagnosis. In group III, 40 consecutive duplicate cervical smears were collected from patients attending the Sexually Transmitted Disease Clinic. One smear was routinely examined, and the specific IF staining was done on the other smear. The results in all the three groups were analysed. It was concluded that Papanicolaou smear is not useful in the detection of Chlamydia trachomatis infection.     

Biodegradation study of crop residues as affected by exogenous inorganic nitrogen and fungal inoculants

The comparative decomposition of chickpea residue, and chopped and unchopped wheat straw was investigated in pits for 120 days. Microbial biomass, humus, C/N ratio, pH, Electrical conductivity (EC), dehydrogenase, alkaline phosphatase, cellulase, xylanase, total phenol and soluble protein were determined to assess their response to the addition of inorganic nitrogen and mixed fungal inoculum of Aspergillus nidulans, Phanerochaete chrysosporium and Trichoderma viride. The evaluation of physico-chemical parameters (organic matter, organic carbon, N, C/N, pH, EC, microbial biomass) revealed that by supplementing unchopped wheat straw with 1% urea and mixed fungal inoculum, a lowest C/N ratio of 10.7, lowest biomass of 9.54 and highest humus content of 13% can be achieved within 3 months. Germination of Lepidium sativum (cress seeds) showed a germination index >60%, in this treatment. The enzyme assay for dehydrogenase indicated highest microbial activity in uninoculated treatments compared to fungal inoculated counterparts, in the second month sampling (active phase of composting). However, cellulase and xylanase activity showed an upward trend during curing phase of composting. Chickpea residue compost, though resulted in a C/N ratio of 17.3, but its germination index was less than 60%. The rapid quality tests conducted for H2S, NH3, NO3 and starch confirmed the stability and maturity of finished compost prepared from wheat straw through microbial inoculants.     

Lymph node 8a as a prognostic marker for poorer prognosis in pancreatic and periampullary carcinoma

Objectives: An investigation of patients with pancreatic carcinoma aims to identify those who will benefit from surgery. Physical examination, radiology and laboratory findings are helpful. Most prognostic markers, such as lymph node status, micro metastasis and tumour differentiation, are not preoperatively accessible. Metastatic disease in lymph node 8a (Ln8a) in patients operated for pancreatic carcinoma has been reported to be a predictor of shorter overall survival (OS). This lymph node can be assessed preoperatively through resection (possibly even with laparoscopy) and subsequent histopathology. The value of the procedure is disputed. The aim of this study is to investigate whether metastatic disease in Ln8a is a predictor of decreased OS.

Materials and methods: In patients with suspected pancreatic or periampullary carcinoma, who were operated with pancreatoduodenectomy (PD), Ln8a was separately resected and analysed with standard and immuno-histochemical methods. Patients with or without metastasis in Ln8a were compared regarding OS.

Results: Between 2008 and 2011, 122 consecutive patients were eligible and 87 were resected and had LN8a analysed separately. Sixteen patients were Ln8a?+?and 71 were Ln8a-. Patients with Ln8a?+?had a significantly reduced median OS as compared to patients with Ln8a– (0.74 (95% CI 0.26–1.26) versus 5.91 years (95% CI 2.91–), p?Conclusion: Ln8a?+?was associated with a marked reduction of OS, indicating a possible role in the future preoperative workup in patients with a suspicion of pancreatic cancer.     

Anticoagulation for coexisting bioprosthetic aortic valve thrombosis and anticoagulant-related bleeding: “A double edge sword”

The choice of anticoagulant agents for newly implanted bioprosthetic valve varies significantly, particularly in the presence of postoperative atrial fibrillation with increasing use of nonvitamin K oral anticoagulation (NOACs) in recent years. We reported a challenging case with a coexisting bioprosthetic aortic valve thrombosis and significant anticoagulant-related bleeding. Clinical management strategy and brief literature review were presented.