LPS mediated injury to oligodendrocytes is mediated by the activation of nNOS: relevance to human demyelinating disease

Loss of oligodendrocytes and the destruction of myelin form the core features of inflammatory demyelinating disease. Although many of the inflammatory and cellular mediators of tissue injury are known, recent studies have suggested an important role for nitric oxide NO and other reactive nitrogen species in oligodendrocyte injury. The human transformed oligodendrocyte cell line, MO3.13 cells, express Toll like receptor genes (TLR) genes and are activated by lipopolysaccharide (LPS). We determined the activation and consequences of neuronal nitric oxide synthase (nNOS) following stimulation with LPS in the MO3.13 cell line. Our studies show that MO3.13 cells induce nNOS following stimulation with LPS. Most importantly, these studies show a susceptibility of MO3.13 cells to NO mediated cell death by the activation of nNOS but not of inducible NOS (iNOS). MO3.13 cells show increased susceptibility to peroxynitrite mediated cellular injury to mitochondrial proteins and decreased cell survival in the presence of LPS. Our studies suggest that the presence and activation of nNOS in oligodendrocytes can directly mediate oligodendrocyte (OC) injury and reduce cell viability.

Multiple novel astrovirus species in human stool

Diarrhoea remains a significant cause of morbidity and mortality in developing countries where numerous cases remain without identified aetiology. Astroviruses are a recently identified cause of animal gastroenteritis which currently includes two species suspected of causing human diarrhoea. Using pan-astrovirus RT-PCR, we analysed human stool samples from different continents for astrovirus-related RNA sequences. We identified variants of the two known human astrovirus species plus, based on genetic distance criteria, three novel astrovirus species all distantly related to mink and ovine astroviruses, which we provisionally named HMOAstV species A-C. The complete genome of species A displayed all the conserved characteristics of mammalian astroviruses. Each of the now three groups of astroviruses found in human stool (HAstV, AstV-MLB and HMOAstV) were more closely related to animal astroviruses than to each other, indicating that human astroviruses may periodically emerge from zoonotic transmissions. Based on the pathogenic impact of their closest phylogenetic relatives in animals, further investigations of the role of HMOAstV, so far detected in Nigeria, Nepal and Pakistan, in human gastroenteritis are warranted.

No association of Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism in susceptibility to gallbladder cancer

Gallbladder carcinoma (GBC) is a leading cause of cancer deaths in north India. Evidence has highlighted the role of abnormal DNA methylation patterns on inappropriate gene expression in development and progression of various cancers. 5,10-Methylenetetrahydrofolate reductase (MTHFR) plays a major role in provision of methyl groups for DNA methylation. A C/T substitution in MTHFR at nucleotide 677 results in replacement of ala222-to-val in the N-terminal catalytic domain of protein, and causes considerable decrease in enzymatic activity. Thus, MTHFR C677T polymorphism may influence genetic susceptibility to GBC. The present study aimed to examine the role of C677T MTHFR polymorphism in conferring genetic susceptibility to GBC. The present study included 146 proven GBC patients and 210 healthy controls. Genotyping was done by PCR-RFLP method. The MTHFR C677T genotypes in control population were in Hardy-Weinberg equilibrium (p = ns). No statistically significant difference was observed in frequency of variant TT genotype in GBC patients in comparison to healthy controls (4.1% and 2.9%). Stratification of GBC patients on the basis of presence or absence of gallstones showed no significant association with the disease. Further, gender and age of onset of the disease did not show any significant association. In conclusion, the present study indicates that the genetic risk for GBC is not modulated by MTHFR C677T polymorphism.

Abscess-a rare fourth ventricular mass

Midline posterior fossa mass lesions in young adults are usually medulloblastomas, pilocytic astrocytomas, haemangioblastomas or ependymomas. We present clinical, imaging and intraoperative findings of an abscess occurring within the fourth ventricle which was associated with right chronic suppurative otitis media and right transverse sinus thrombosis. The possible pathogenesis is discussed.

Detoxification reactions of sulphur mustard on the surface of zinc oxide nanosized rods

Detoxification reactions of sulphur mustard, a deadliest chemical warfare agent were studied on the surface of zinc oxide nanorods at room temperature (32+/-2 degrees C) and the data was compared with that of the bulk ZnO. Prior to the reaction, the nanorods of zinc oxide were synthesized by the hydrothermal method and subsequently characterized by XRD, SEM, TG, N(2) BET, FT-IR. The data revealed the formation of nanorods with diameter ranging from 100 nm to 500 nm with length in microns. Obtained nanomaterial along with bulk ZnO were tested as reactive sorbent for the detoxification of sulphur mustard. Reaction was monitored by GC-FID technique and the reaction products were characterized by GC-MS. Data explores the role of hydrolysis and elimination reactions in the detoxification of sulphur mustard and it also reveals that zinc oxide nanorods and bulk ZnO show the half lives of 8.48 h, 24.75 h in the first 12h and 122.47 h, 177.29 h from 12h to 48 h of the reaction.

Predictable and avoidable human errors in phlebotomy area ? an exclusive analysis from a tertiary health care system blood bank

Error is a direct reflection of system deficiency. Errors occurring in the phlebotomy area are grossly unreported. Though most of these errors does not lead to catastrophic outcome yet indicate system failure. The aim of the study was to identify errors that took place in phlebotomy area, analysing and classifying them. A prospective audit was conducted during an observational period of 8 months, in an overall cohort of 11 260 donors. The incidence of errors was 3.1%. Fifty-five percent errors were technical and remaining 44.9% were clerical. Of all the technical errors, 57.7% were classified as minor, whereas remaining 42.3% were of major category. Similarly, majority of clerical errors (89.9%) were of minor category. The trained staff accounted for all major events (27.8%). In the minor category, technical errors (73.2%) were more commonly done by trained staff, whereas for clerical errors (58.5%), newly recruited staff was responsible. Errors in phlebotomy area are benign but can compromise donor safety. The study helped to develop a consistent and straightforward classification system for errors and to reduce them by basic interventions. Errors committed mostly by our trained staff indicate the need of regular competency testing and an active system for detection of these deviations.

Microbial decolorization and bioremediation of melanoidin containing molasses spent wash

Molasses spent wash from cane-molasses based distilleries contains a brown coloured recalcitrantpolymer melanoidin, which if disposed untreated poses a great threat to environment. Microbial decolorization and chemical oxygen demand (COD) reduction was found to be dependent on specific carbon and nitrogen source. Under optimal condition of pH, carbon and nitrogen concentration for each treatment, it was found that Bacillus sp isolated from soil was capable of removing COD (85. 35%) and colour (81.10%) from distillery waste to the maximum extent after 9 days atpH 7 in the medium containing 0.5% peptone, 2% glucose and 10% (v/v), followed by Phanerochaete chrysosporium and lowest reduction was obtained by using native microbial consortium.

A prospective comparison of four techniques for diagnosis of paroxysmal nocturnal hemoglobinuria

Paroxysmal nocturnal hemoglobinuria (PNH) is an acquired clonal stem cell disorder with altered expression of glycosylphosphatidylinositol (GPI)-anchored proteins, resulting in the increased susceptibility of erythrocytes to complement-mediated lysis. This study compared the available laboratory methods for detection of PNH cells and evaluated their utility in routine clinical practice. Fifty patients were evaluated by flow cytometric immunophenotyping (FCMI) using CD55 and CD59 monoclonal antibodies, PNH gel card test (GCT), Ham test and sucrose lysis test (SLT). A PNH clone was detectable in erythrocytes in 14 (28%) patients by FCMI, 13 (26%) by GCT and 10 (20%) by Ham test and SLT. The GCT and lytic tests showed 100% specificity and sensitivity was 92.8% and 71.1%, respectively. The GCT results correlated with type III cells (positive for > or =3.21% type III cells) and lytic test results correlated with CD59(-) type III cells (positive for > or =5% CD59(-) type III cells). The GCT and lytic tests were comparable in their sensitivity to detect type II cells (positive for > or =18.5% type II cells). Among the available methods, FCMI is most sensitive, can quantify and delineate PNH cells with differential expression of GPI-anchored proteins. The GCT is a useful screening tool as it is fairly sensitive, easy to perform and interpret. Well-standardized lytic tests are fairly reliable as screening tests.

Foot drop after spinal anesthesia in a patient with a low-lying cord

Damage to the spinal cord/conus medullaris due to incorrect identification of the lumbar space is a known complication of lumbar puncture. However, damage to a low-lying cord using an appropriate interspace is extremely rare. We describe a 26-year-old woman who underwent emergency caesarean section under spinal anesthesia. She developed right foot drop immediately after surgery, which gradually recovered over the next 10 months. Magnetic resonance imaging revealed a low lying cord with a fatty filum terminale and intramedullary T2 hyperintensity, suggestive of needle damage.

Pediatric pituitary adenoma: a series of 42 patients

Pituitary adenomas are uncommon in childhood. This report describes the presentation, endocrinological profile, management and outcome of 42 children with pituitary adenomas. The majority of the tumors were functioning adenomas (40/42, 95.2%). Only two patients (4.8%) had non-functioning tumors. Amongst the functioning tumors, there were 20 patients (47.6%) with prolactinomas, 11 patients (26.2%) with Cushing's disease and nine patients (21.4%) with growth hormone (GH)-secreting adenomas. The most common presenting features were endocrinopathy and visual disturbances. The majority of tumors were macroadenomas, with only eight patients (all with Cushing's disease) having a microadenoma. Transsphenoidal tumor decompression was performed in most cases (71.4%). Complications following transcranial surgery were more frequent when compared to transsphenoidal surgery. There was one death following surgery. Response to radiotherapy was satisfactory. Overall, 67.6% of patients achieved endocrinological remission. Of these, 89% of the children with GH-secreting tumors and 100% of the children with Cushing's disease achieved remission. We conclude that the transsphenoidal approach is effective and safe in surgery for pituitary adenomas in children and is the procedure of choice if there is no contraindication. The combination of surgery and radiotherapy, as well as medical therapy with bromocriptine, achieves good results in the management of these uncommon tumors.

Brain abscess--an unusual complication of ventriculo-peritoneal shunt

The authors report a case of a 10-year-old boy, who was operated for a craniopharyngioma with hydrocephalus. He succumbed to delayed development of brain abscess and its consequence, secondary to incompletely treated shunt tract infection. This unfortunate complication developed, despite the fact that conventional steps (removal of VP shunt and intravenous antibiotics) recommended for the treatment of VP shunt infection were adopted. The pathogenesis, management and review of literature of this extremely rare clinical entity is presented.

Rhizobia as a biological control agent against soil borne plant pathogenic fungi

Rhizobia promote the growth of plants either directly through N2 fixation, supply of nutrients, synthesis of phytohormones and solubilization of minerals, or indirectly as a biocontrol agent by inhibiting the growth of pathogens. The biocontrol effect of rhizobia is due to the secretion of secondary metabolites such as antibiotics and HCN. Siderophore production in iron stress conditions provides rhizobia an added advantage, resulting in exclusion of pathogens due to iron starvation.

Subarachnoid hemorrhage and intracereebral hematoma following lumboperitoneal shunt for pseudotumor cerebri: a rare complication

Placement of lumboperitoneal (LP) shunt as a surgical treatment for benign intracranial hypertension (BIH) is generally a safe procedure, with complications like mechanical failure, overdrainage and infections. Subarachnoid hemorrhage and intracerebral hematoma were seen after lumboperitoneal shunt in a patient having BIH. These complications were the cause of the patient's deterioration. After removal of the hematoma and performing a decompressive procedure, patient's neurological condition improved. The clinical features, investigations and clinical course are described and the literature reviewed.