Cytodiagnosis of eumycotic mycetoma: a case report

BACKGROUND: Mycetoma is a late-stage clinical manifestation of a subcutaneous infection produced by bacteria (actinomycetoma) or fungi (eumycetoma). Only a few articles have described the morphologic appearance of this uncommon pathology on cytology. The distinction between eumycetoma and actinomycetoma in fine needle aspiration cytology (FNAC) is as accurate as in histopathology, as demonstrated in the present case. CASE: A 30-year-old man presented with a large swelling on his left foot with a discharging sinus. FNAC of the swelling yielded pus-like material. Initial Papanicolaou and Giemsa stains showed the presence of septate, branching fungal hyphae and black granules against the inflammatory background. The presence of fungus was confirmed by PAS stain. The species was identified as Exophiala jeanselmei on fungal culture. CONCLUSION: Mycotic mycetoma can be accurately diagnosed by FNAC, which is a simple, inexpensive and rapid technique when there is a high index of suspicion. Special stains and culture studies are helpful in confirmation of diagnosis and species identification.     

Evaluation of Ssp I polymerase chain reaction assay in the detection of Wuchereria bancrofti infection in field-collected Culex quinquefasciatus and its application in the transmission studies of lymphatic filariasis

Abstract: Ssp I polymerase chain reaction (PCR) assay, developed for Wuchereria bancrofti, was evaluated for its sensitivity in detecting infection in the vector, Culex quinquefasciatus, in the field. The evaluation of the assay was carried out using pools of vector mosquitoes collected from areas under filariasis survey and control trial projects, in comparison with the standard dissection and microscopy technique. In the filariasis survey area the infection rate as determined by the dissection and microscopy technique was 0.89% whereas it was 1.7% by PCR assay. In the Bacillus sphaericus trial area the infection rates as assessed by the conventional technique were 6.6 and 4.5% in the treated and check areas, respectively, whereas those obtained by the PCR assay were 4.7 to 2.2%. Although the infection rates determined by the PCR assay are slightly higher or lower than the rates obtained by the conventional technique, the difference was not statistically significant (P=0.451 for filariasis survey area, and P=0.203 and 0.161 for B. sphaericus trial area). When the pool size of Cx. quinquefasciatus was increased to 50 the sensitivity of the PCR was affected. The changes in infection rates as influenced by the antifilarial chemotherapy were similar when determined by PCR assay and the standard method. The major advantage of the PCR assay over the conventional technique is that thousands of mosquitoes can be processed within a short duration and this attribute has potential application in rapid assessment of disease prevalence and monitoring of the transmission dynamics.     

Draft Genome Sequence of Staphylococcus aureus ST672, an Emerging Disease Clone from India

We report the draft genome sequence of methicillin-resistant Staphylococcus aureus (MRSA) strain ST672, an emerging disease clone in India, from a septicemia patient. The genome size is about 2.82 Mb with 2,485 open reading frames (ORFs). The staphylococcal cassette chromosome mec (SCCmec) element (type V) and immune evasion cluster appear to be different from those of strain ST772 on preliminary examination.     

R‐loop induced stress response by second (p)ppGpp synthetase in Mycobacterium smegmatis: functional and domain interdependence

Persistent R‐loops lead to replicative stress due to RNA polymerase stalling and DNA damage. RNase H enzymes facilitate the organisms to survive in the hostile condition by removing these R‐loops. MS_RHII‐RSD was previously identified to be the second (p)ppGpp synthetase in Mycobacterium smegmatis. The unique presence of an additional RNase HII domain raises an important question regarding the significance of this bifunctional protein. In this report, we demonstrate its ability to hydrolyze R‐loops in Escherichia coli exposed to UV stress. MS_RHII‐RSD gene expression was upregulated under UV stress, and this gene deleted strain showed increased R‐loop accumulation as compared to the wild type. The domains in isolation are known to be inactive, and the full length protein is required for its function. Domain interdependence studies using active site mutants reveal the necessity of a hexamer form with high alpha helical content. In previous studies, bacterial RNase type HI has been mainly implicated in R‐loop hydrolysis, but in this study, the RNase HII domain containing protein showed the activity. The prospective of this differential RNase HII activity is discussed. This is the first report to implicate a (p)ppGpp synthetase protein in R‐loop‐induced stress response.     

Two picrotoxin derivatives from Anamirta cocculus

The berries of the plant Anamirta cocculus afforded picrotin, picrotoxinin, methyl picrotoxate and two new sesquiterpene γ-lactones, dihydroxypicrotoxinin and picrotoxic acid, whose structures were determined by spectroscopic methods.     

Lowering of intraocular pressure by topical application of Daucus carota seed extract in rabbits

In normotensive rabbits topical application of Daucus carota seed extract at the concentration of 0.3, 0.6 and 1.2% resulted in mean IOP reduction of 19.33. 23.20 and 25.61% respectively from baseline. As no significant difference was observed between the change in IOP in 0.6 and 1.2% extract treated groups, 0.6% concentration was chosen for further evaluation in rabbits with experimentally elevated IOP. In water loaded rabbits, maximum mean IOP reduction with 0.6% extract was 29.39%, which was comparable to pilocarpine. In steroid pretreated rabbits, maximum mean IOP reduction was 30.27% from baseline, which was significantly higher than pilocarpine. The extract showed a comparatively slower onset of action however, the duration of action was comparable to pilocarpine in all the experimental models.     

Clear and independent associations of several HLA-DRB1 alleles with differential antibody responses to hepatitis B vaccination in youth

To confirm and refine associations of human leukocyte antigen (HLA) genotypes with variable antibody (Ab) responses to hepatitis B vaccination, we have analyzed 255 HIV-1 seropositive (HIV⁺) youth and 80 HIV-1 seronegatives (HIV^?) enrolled into prospective studies. In univariate analyses that focused on HLA-DRB1, -DQA1, and -DQB1 alleles and haplotypes, the DRB1*03 allele group and DRB1*0701 were negatively associated with the responder phenotype (serum Ab concentration ≥ 10 mIU/mL) (P = 0.026 and 0.043, respectively). Collectively, DRB1*03 and DRB1*0701 were found in 42 (53.8%) out of 78 non-responders (serum Ab <10 mIU/mL), 65 (40.6%) out of 160 medium responders (serum Ab 10–1,000 mIU/mL), and 27 (27.8%) out of 97 high responders (serum Ab >1,000 mIU/mL) (P < 0.001 for trend). Meanwhile, DRB1*08 was positively associated with the responder phenotype (P = 0.010), mostly due to DRB1*0804 (P = 0.008). These immunogenetic relationships were all independent of non-genetic factors, including HIV-1 infection status and immunodeficiency. Alternative analyses confined to HIV⁺ youth or Hispanic youth led to similar findings. In contrast, analyses of more than 80 non-coding, single nucleotide polymorphisms within and beyond the three HLA class II genes revealed no clear associations. Overall, several HLA-DRB1 alleles were major predictors of differential Ab responses to hepatitis B vaccination in youth, suggesting that T-helper cell-dependent pathways mediated through HLA class II antigen presentation are critical to effective immune response to recombinant vaccines.