Intraoperative angiography for cranial dural arteriovenous fistula

BACKGROUND AND PURPOSE

IA is a valuable adjunct during surgery for a variety of neurovascular diseases; however, there are no reported series describing IA for DAVFs. This study was undertaken to evaluate the safety and efficacy of IA for DAVFs.

MATERIALS AND METHODS

A retrospective review of DAVF surgical cases during a 20-year period was conducted, and cases with IA were evaluated. Clinical details, surgical and angiographic findings, and postoperative outcomes were reviewed. The incidence of residual fistula on IAs, the utility of the surgical procedure, and the incidence of false-negative findings on IA were also determined.

RESULTS

IA was performed in 29 patients (31 DAVFs) for DAVFs. The distribution of the fistulas was the following: transverse-sigmoid (n = 9), tentorial (n = 6), torcular (n = 3), cavernous sinus (n = 4), SSS (n = 4), foramen magnum (n = 3), and temporal-middle fossa (n = 2). Twelve patients had undergone prior embolization, while 6 patients had unsuccessful embolization procedures. Thirty-eight surgeries were performed for DAVF in 29 patients, and IA was performed in 34 surgeries. Forty-four angiographic procedures were performed in the 34 surgeries. Nine patients underwent multiple angiographies. In 11 patients (37.9%), IA revealed residual fistula after the surgeon determined that no lesion remained. This led to further exploration at the same sitting in 10 patients, while in 1 patient, further surgery was performed at a later date. False-negative findings on IA occurred in 3 patients (10.7%).

CONCLUSIONS

IA is an important adjunct in surgery for DAVF. In this series, it resulted in further surgical treatment in 37.9% of patients. However, there was a 10% false-negative rate, which justified subsequent postoperative angiography.

An affinity-based genome walking method to find transgene integration loci in transgenic genome

Identifying a good transgenic event from the pool of putative transgenics is crucial for further characterization. In transgenic plants, the transgene can integrate in either single or multiple locations by disrupting the endogenes and/or in heterochromatin regions causing the positional effect. Apart from this, to protect the unauthorized use of transgenic plants, the signature of transgene integration for every commercial transgenic event needs to be characterized. Here we show an affinity-based genome walking method, named locus-finding (LF) PCR (polymerase chain reaction), to determine the transgene flanking sequences of rice plants transformed by Agrobacterium tumefaciens. LF PCR includes a primary PCR by a degenerated primer and transfer DNA (T-DNA)-specific primer, a nested PCR, and a method of enriching the desired amplicons by using a biotin-tagged primer that is complementary to the T-DNA. This enrichment technique separates the single strands of desired amplicons from the off-target amplicons, reducing the template complexity by several orders of magnitude. We analyzed eight transgenic rice plants and found the transgene integration loci in three different chromosomes. The characteristic illegitimate recombination of the Agrobacterium sp. was also observed from the sequenced integration loci. We believe that the LF PCR should be an indispensable technique in transgenic analysis.

Genetic architecture, inter-relationship and selection criteria for yield improvement in rice (Oryza sativa L.)

This study has been conducted to determine the extent of genetic association between yield of Rice (Oryza sativa L.) and its components. The present experiment was carried out with 40 Rice (Oryza sativa L.) genotypes which were evaluated in a randomized block design with 3 replications during wet season of 2007 and 2008. Results showed that sufficient amount of variability was found in the entire gene pool for all traits studied. Higher magnitude of genotypic and phenotypic coefficients of variation was recorded for seed yield, harvest index, biological yield, number of spikelets per panicle, flag leaf length, plant height and number of tillers indicates that these characters are least influence by environment. High heritability coupled with high genetic advance as percent of mean was registered for seed yield, harvest index, number of spikelets per panicle, biological yield and flag leaf length, suggesting preponderance of additive gene action in the expression of these characters. Grain yield was significantly and positively associated with harvest index, number of tillers per hill, number of panicle per plant, panicle length, number of spikelet's per panicle and test weight at both genotypic and phenotypic levels. Path coefficient analysis revealed that harvest index, biological yield, number of tillers per hill, panicle length, number of spikelets per panicle, plant height and test weight had direct positive effect on seed yield, indicating these are the main contributors to yield. From this study it may be concluded that harvest index, number of tillers per hill, panicle length and number of spikelet per panicle and test weight are the most important characters that contributed directly to yield. Thus, these characters may serve selection criteria for improving genetic potential of rice.

Does CSF composition predict shunt malfunction in tuberculous meningitis?

BACKGROUND

Hydrocephalus secondary to tuberculous meningitis (TBM) continues to be a challenging condition to treat for neurosurgeons in developing countries. Shunt complications are reportedly more frequent in patients undergoing ventriculo-peritoneal shunt in patients with TBM than in those undergoing shunt surgeries for other causes.

AIM

The aim of this study was to evaluate the relationship of cerebrospinal fluid (CSF) composition on shunt malfunction.

METHODS

We compared the CSF composition of 53 patients who had shunt malfunction during a five year period with that of 137 matched controls.

RESULTS

Patients who had shunt malfunction had a significantly higher concentration of CSF protein. The CSF cellularity and glucose concentration did not have any significant bearing in predicting shunt malfunction. Patients with CSF protein concentration of more than 200 mg/dL had a four times higher risk of having shunt malfunction than those with a concentration of less than 100 mg/dL. Patients with CSF protein in the 100-200 mg/dL range represent an intermediate zone.

CONCLUSION

To conclude, patients with CSF protein concentration of more than 200 mg/dL have a significantly higher risk of shunt malfunction and hence have to be followed up closely.

Assessment of urban air pollution and it's probable health impact

The present study deals with the quantitative effect of vehicular emission on ambient air quality during May 2006 in urban area of Lucknow city. In this study SPM, RSPM, SO2, NOx and 7 trace metals associated with RSPM were estimated at 10 representative locations in urban area and one village area for control. Beside this, air quality index (AQI), health effects of different metals and mortality were assessed. The 24 hr average concentration of SPM, RSPM, SO2 and NOx was found to be 382.3, 171.5, 24.3 and 33.8 microg m(-3) respectively in urban area and these concentrations were found to be significantly (p < 0.01) higher by 94.8, 134.8, 107.4 and 129.6% than control site respectively The 24 hr mean of SPM and RSPM at each location of urban area were found to be higher than prescribed limit of National Ambient Air Quality Standard (NAAQS) except SPM for industrial area. The 24 hr mean concentration of metals associated with RSPM was found to be higher than the control site by 52.3, 271.8, 408.9, 75.81, 62.7, 487.54 and 189.5% for Fe, Cu, Pb, Zn, Ni, Mn and Cr respectively. The inter correlation of metals Pb with Mn, Fe and Cr; Zn with Ni and Cr; Ni with Cr; Mn with Fe and Cu with Cr showed significant positive relation either at p < 0.05 or p < 0.01 level. Metals Pb, Mn and Cr (p < 0.01) and Cu (p < 0.05) showed significant positive correlation with RSPM. These results indicate that ambient air quality in the urban area is affected adversely due to emission and accumulation of SPM, RSPM, SO2, NOx and trace metals. These pollutants may pose detrimental effect on human health, as exposure of these are associated with cardiovascular and respiratory diseases, neurological impairments, increased risk of preterm birth and even mortality and morbidity.

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.