Risk factors and outcome analysis of patients with intraoperative rupture (IOR) of ruptured cerebral aneurysm during microsurgical clipping.

PURPOSE: To analyse baseline characteristics of patients with intraoperative rupture (IOR) or non-IOR who underwent microsurgical clipping for ruptured intracranial aneurysms. Additionally, to asses functional outcome in terms of Glasgow Outcome Scale (GOS) at 6 and 12 months. METHODS: A retrospective analysis of 471 patients who underwent microsurgical clipping for ruptured intracranial aneurysms from 2007 to 2018 in Nepal Mediciti Hospital, Nepal. Patients who underwent surgery for unruptured aneurysm were excluded from the study. The association of the base line characteristic in IOR and non-IOR were analysed. Variables analysed were the Hunt and Hess Scale (HHS) dichotomized as (1-3) and (4-5), Modified Fisher Scale dichotomized as (0-2) and (3-4), type of rupture, use of brain retractor, timing of IOR during surgery, aneurysmal factors (size of the neck, location, lobulation) and time of surgery. Outcome, GOS dichotomized into favourable (4-5) and unfavourable (1-3), assessed at 6 months and 12 months. RESULTS: Out of 471 patients treated for ruptured intracranial aneurysm, IOR occurred in 57 (12.10%) with mean age 49.47 (SD ±12.9), occurred more in smoker than non-smoker (45.6% vs. 18.6%; p=.000) and regular alcohol consumers (36.8% vs. 17.9%; p=.004). Favourable outcome with GOS (4-5) at 6 months was observed among patients with lower HHS (1-3), p=.025 and lower MFS (0-2), p=.04. However, outcome at 12 months was better associated with MFS (p=.013) and aneurysm size (p=.038), with more favourable outcome associated with aneurysm less than 10 mm. CONCLUSIONS: Alcohol consumption and smoking are associated risk factors that may contribute to IOR. HHS and MFS are strong predictors of outcome for IOR patients at 6 months. However, at 12 months, MFS is more predictive of outcome. Aneurysms greater than 10 mm had a strong association with outcome at 12 months than 6 months.

Prevalence of metabolic syndrome in an urban Indian diabetic population using the NCEP ATP III guidelines.

OBJECTIVE: To study the prevalence of metabolic syndrome (MetS) in an urban Indian diabetic population. RESEARCH DESIGN AND METHODS: A total of 5088 type 2 diabetes patients (2908 men and 2180 women) presenting to endocrinology clinics at four centers across Mumbai (a large metropolitan city in India) were selected for the study. Anthropometric (waist circumference), clinical (blood pressure) and biochemical (serum triglycerides, HDL, fasting and post-prandial blood glucose) data were recorded. Patients receiving treatment for hypertension or dyslipidemia were also included in the study and these were considered in the diagnosis of MetS even if the parameters were normal. The National Cholesterol Education Program Adult Treatment Panel III guidelines were used to diagnose MetS. The chi-square test was used to determine statistical significance, which was taken as a p value < 0.05. RESULTS: The prevalence of MetS among urban Indian diabetic patients was 77.2% and was significantly higher in women (87.71%) as compared to men (69.33%) (p < 0.0001). The most prevalent risk factors for MetS were hypertension, followed by hypertriglyceridemia, in men, and central obesity, followed by hypertension, min women. CONCLUSIONS: MetS is highly prevalent in the urban Indian diabetic population. It should be identified by regular screening in individuals from the general population to avert or delay the progression to type 2 diabetes in order to reduce diabetes-related morbidity and mortality.

Detection of Clostridium perfringens enterotoxin in stool specimens and culture supernatants by enzyme-linked immunosorbent assay.

An enzyme-linked immunosorbent assay was developed to detect and quantitate Clostridium perfringens enterotoxin A in culture supernatants and in stool specimens from cases of diarrhea in which high numbers of enterotoxin-producing Clostridium perfringens were isolated. To analyze for enterotoxin A, polyvinyl chloride microtiter plates were coated with dilute immune whole rabbit serum. Enterotoxin A standards and samples were allowed to react with sensitized wells. The presence of the immobilized antigen in the wells was detected by the binding of immune rabbit immunoglobulin conjugated with peroxidase. Nanograms of enterotoxin were detectable. Four enterotoxin-positive and seven enterotoxin-negative cultures grown in Duncan-Strong medium gave expected results. Eighteen of 23 diarrheal stool specimens obtained after a food-poisoning outbreak at a state hospital were found to contain microgram quantities of enterotoxin per gram of stool, whereas five control diarrheal specimens contained less than 0.6 ng enterotoxin per gram of stool. These results indicate that the enzyme-linked immunosorbent assay technique is useful for differentiating enterotoxigenic strains and for diagnosing diarrhea caused by enterotoxigenic Clostridium perfringens.

Lead removal from foundry waste by solvent extraction.

Solvent extraction is used to reduce lead concentrations from millpond wastewater solids, a type of foundry process waste. Toluene and toluene mixed with di-(2-ethyl-hexyl) phosphoric acid (HDEHP) have been tried as leaching solvents. Toluene is ineffective as a solvent in extracting lead, but the toluene-HDEHP mixture effectively removes lead from solid foundry waste. The effects of the HDEHP concentration, the contact time, and the amount of solvent used on lead extraction have been investigated. The mass transfer process is rapid: contact time of 1/2 hour has been found to be sufficient to accomplish the leaching process. The concentration of HDEHP significantly impacts lead removal. The optimum concentration of HDEHP is determined to range from 0.05 to 0.1 mol/l. The Toxicity Characteristic Leaching Procedure (TCLP) test of the treated samples gives leachable lead in much lower quantities than those found in the untreated samples. Thus the solvent extraction process appears to be an effective method to significantly reduce the lead content of millpond wastewater solids.

Replication and recombination of gene 59 mutant of bacteriophage T4D.

After infection of Escherichia coli B with phage T4D carrying an amber mutation in gene 59, recombination between two rII markers is reduced two- to three-fold. This level of recombination deficiency persists even when burst size similar to wild type is induced by the suppression of the mutant DNA-arrest phenotype. In the background of two other DNA-arrest mutants in genes 46 and 47, a 10- to 11-fold reduction in recombination is observed. The cumulative effect of gene 59 mutation on gene 46-47 mutant suggests that complicated interactions must occur in the production of genetic recombinants. The DNA-arrest phenotype of gene 59 mutant can be suppressed by inhibiting the synthesis of late phage proteins. Under these conditions, DNA replicative intermediates similar to those associated with wild-type infection are induced. Synthesis of late phage proteins, however, results in the degradation of mutant 200S replicative intermediate into molecules are associated with membrane, they do not replicate. These results suggest a role for gene 59 product, in addition to a possible requirement of concatemeric DNA in late replication of phage T4 DNA.

Enzyme immunoassay for detection of Drosophila melanogaster antigens in the juice of various foods.

An enzyme immunoassay (EIA) was developed to identify and quantitate soluble antigens originating from Drosophila melanogaster eggs. Polystyrene microtiter plates were coated with anti-egg antibody. Egg antigen standards or samples were reacted with the sensitized wells. The immobilized antigen was reacted with biotinylated antibody, and the complex was quantitated by an avidin-horseradish peroxidase conjugate. The assay can detect egg antigens equivalent to 0.03 eggs/mL. The antibody was directed against a number of antigens and cross-reacted with extracts of adult Drosophila melanogaster flies. Homogenized eggs diluted in various juice samples were detectable by EIA. Heating the antigen diluted in buffer or juice at a temperature used in processing of juice reduced the immunological response approximately 40-45%. Brine separated from fresh-packed sauerkraut showed EIA responses equivalent to 0.3-3 eggs/mL. Electrophoretic, chromatographic, and immunological analyses suggested that the EIA responses for sauerkraut brine were related to the Drosophila melanogaster egg antigens.

Effect of a gene-specific suppressor mutation (das) on DNA synthesis of gene 46-47 mutants of bacteriophage T4D.

Mutants in genes 46 and 47 of bacteriophage T4 exhibit early cessation of DNA synthesis, inability to form a normal rapidly sedimenting DNA intermediate (200S), reduced genetic recombination, and reduced viable phage production. A gene-specific suppressor mutation called das partially restores many of the pleiotropic effects of gene 46-47 mutants (13). Our results indicate that this partial suppression by das is associated with (i) the synthesis of a small fraction of DNA containing long single chains not detectable in 46-47 infection and (ii) a decrease in an "early" function which participates in the degradation of DNA synthesized in the absence of 46-47 functions. However, das does not restore the formation of a normal rapidly sedimenting (200S) DNA intermediate.

Suppression of gene 49 mutations of bacteriophage T4 by a second mutation in gene X: structure of pseudorevertant DNA.

Mutations in gene 49 of bacteriophage T4 were suppressed by a second mutation in gene X. Mapping studies located gene X between genes 41 and 42. Complementation results indicated that mutations in FdsA gene (a suppressor of gene 49 mutants) were in gene X. The intracellular pseudorevertant DNA was examined for unusual properties which could explain its successful encapsidation. After the in vivo inactivation of a temperature-sensitive gene 32 (DNA unwinding) protein, the intracellular pseudorevertant DNA was converted into DNA pieces of approximately genome size. A similar conversion was observed after in vitro digestion of pseudorevertant DNA with single-strand-specific S1 endonuclease. Appreciable quantities of oligomeric intermediates were not produced during this conversion process. These data indicate that pseudorevertant DNA contains sizable single-stranded gaps and has a conformation similar to that of wild-type DNA. The results further suggest that the suppression of gene 49 mutant abnormal DNA phenotype and the encapsidation defect by a second mutation in gene X is associated with the formation of sizable single-stranded gaps. These studies raise the possibility that single-stranded gaps may be involved directly in the DNA encapsidation process, or may act indirectly as a consequence of their effect on the organization of intracellular DNA.

Application of pulsed-field gel electrophoresis to the epidemiological characterization of Staphylococcus intermedius implicated in a food-related outbreak.

An outbreak of food intoxication involving over 265 cases in western United States occurred in October 1991. Staphylococcus intermedius was implicated as the aetiologic agent. Representative outbreak isolates (five clinical and ten from foods) produced type A enterotoxin. DNA fragments generated by four restriction endonucleases and analysed by pulsed-field gel electrophoresis (PFGE) provided definitive evidence that all isolates from nine different counties in California and Nevada were derived from a single strain. The PFGE pattern of these outbreak isolates was distinct from those of a heterogeneous collection of seven S. intermedius strains of veterinary origin and five unrelated S. aureus laboratory strains. The data show a significant PFGE pattern heterogeneity not only among members of different Staphylococcus species but also within members of the same species and even the same enterotoxin type. The results indicate that PFGE is a valuable strain-specific discriminator for the epidemiological characterization of S. intermedius. To our knowledge, this represents the first documented foodborne outbreak caused by S. intermedius. These findings suggest that the presence of S. intermedius and other species such as S. hyicus in food should be reason for concern.

Replication and recombination in ligase-deficient rII bacteriophage T4D.

Deoxyribonucleic acid replication and genetic recombination were investigated after infection of Escherichia coli with ligase-deficient rII bacteriophage T4D. The major observations are: (i) deoxyribonucleic acid synthesis is discontinuous, (ii) the discontinuities are more slowly repaired than in wild-type infection, (iii) host ligase is required for viability, and (iv) genetic recombination is increased.

Isolation and characterization of a cytolysin produced by Vibrio cholerae serogroup non-O1.

A thermolabile toxin (molecular weight, 52 711; isoelectric point, 8.65) produced by a clinical isolate of Vibrio cholerae serogroup non-O1 was cytotoxic for Y-1 mouse adrenal cells and Chinese hamster ovary cells. The toxin lysed rabbit red blood cells and produced a hemorrhagic zone in rabbit skin. When injected intravenously into adult mice, the cytolysin was rapidly lethal and caused fluid accumulation in both 5- and 18-h rabbit ileal loops. Strains of V. cholerae that produced cytolysin but no cholerae enterotoxin were able to cause fluid accumulation in rabbit intestinal loops.

Detection of Enterotoxin in Colonies of Clostridium perfringens by a Solid Phase Enzyme-Linked Immunosorbent Assay.

A nitrocellulose colony-blot assay was developed to detect enterotoxigenic strains of Clostridium perfringens on an agar medium. To enhance sporulation and enterotoxin production, a number of modifications of the Duncan-Strong (D-S) medium were tested, including the substitution of raffinose for starch and the addition of theobromine, papaverine and various combinations of soil and fecal extracts. Colonies of enterotoxigenic strains were most consistently positive and produced the most intense color reactions on a modified D-S medium containing raffinose, theobromine and 50% (vol/vol) bovine fecal extract. This modified medium stimulated production of detectable enterotoxin by colonies in more than 90% of the enterotoxigenic strains tested. No false-positive reactions were observed. This enzyme-linked, immunosorbent assay (ELISA) was not as effective in the analysis of broth cultures or fecal samples. Our results indicate that the nitrocellulose colony-blot assay will be useful for screening enterotoxigenic strains in epidemiologic studies.

In vitro assay of Staphylococcus aureus enterotoxin A activity in food.

Staphylococcus aureus enterotoxin A (SEA) is a leading cause of food poisoning. The current test for functional activity of SEA requires monkeys or kittens. The major drawbacks of animal assays are lack of quantitation, poor reproducibility, low sensitivity, and high cost. In this report we describe and evaluate an alternative assay using T-cell proliferation to measure SEA activity in food. Human and rat lymphocytes proliferate in response to concentrations of SEA as low as 1 pg/ml, well below the pathogenic dose of 100 ng. This proliferation assay is highly sensitive, quantitative, and simple. Nonradioactive assays of T-cell proliferation were also suitable for detecting and measuring SEA, although with a 10-fold lower sensitivity. To evaluate the utility of this assay for food testing, four different food samples were mixed with SEA. In each sample, SEA was detected at a concentration of 1 ng/ml. Heat-inactivated SEA produced no detectable proliferation. These results demonstrate that an in vitro cell proliferation assay is an advantageous alternative to existing animal assays for measuring SEA activity in food.

Detection of heat-labile-enterotoxin-producing colonies of Escherichia coli and Vibrio cholerae by solid-phase sandwich radioimmunoassays.

A solid-phase sandwich assay that was able to differentiate heat-labile-enterotoxin-producing colonies of Escherichia coli and choleratoxin-producing colonies of Vibrio cholerae from nontoxigenic colonies is described. Flexible polyvinyl chloride plastic film coated with antibody molecules was allowed to react with partially lysed bacterial colonies in a standard petri dish. The immobilized antigen on the plastic film was then labeled with radioiodinated antibody. Autoradiography identified antigen-containing colonies. As little as 5 to 25 pg of pure toxin contained in a 3- to 4-mm-diameter circle was reliably detected by this method. The synthesis of heat-labile enterotoxin and choleratoxin by cells growing on selective media such as eosin methylene blue agar, MacConkey agar, Endo agar, and thiosulfate-citrate-bile salts-sucrose agar was demonstrated. The method appears to be suitable for large-scale surveys.

The technetium white cell scan as an initial imaging investigation for evaluating suspected childhood inflammatory bowel disease.

BACKGROUND: The technetium white cell scan (WCS) may be a useful investigation for patients with inflammatory bowel disease (IBD). In a retrospective study we assessed the use of the WCS as an initial imaging investigation in evaluating children with suspected IBD. METHODS: Over a 3-year period, 60 WCS were performed on 55 patients (25 boys, median age 12.1 years, age range 1.5-18 years) with known or suspected IBD. There were two clinical groups: those with previously diagnosed IBD (histologically and radiologically) and in clinical relapse (13 patients), and newly presenting patients with suspected IBD (42 patients). RESULTS: Eighteen scans were performed on the 13 patients presenting with relapse. Seventeen were positive and one patient, subsequently shown to have an inactive stricture, had a negative scan. Seven of the 42 newly presenting patients had abnormal scans, confirmed to be due to IBD by a combination of histology and barium examinations. Of the remaining 35 scans, three were abnormal and 32 were normal. None of these patients were subsequently proven to have IBD. These results show that in detecting active IBD, a positive WCS has a 100% sensitivity (24/24) and a 91% specificity (32/35) in the diagnosis of IBD. CONCLUSIONS: Our results show that the WCS is very useful as an initial imaging investigation in evaluating patients with suspected IBD to select patients for further investigation.

Comparison of helium leak test and vacuum leak test using canned foods: collaborative study.

Two can leak tests were compared by 7 collaborators. In the helium leak test, pressurized helium is applied to the outside of the container, and a headspace gas sample from the can is then analyzed for the presence of helium. The vacuum test is described in the Bacteriological Analytical Manual. Ninety No. 303 cans of creamed-style corn, green beans, carrots, fruit cocktail, and whole-kernel corn were shipped in 3 groups. Two groups of 30 cans had 10 dented flat cans, 5 flat controls (nondented), 10 dented swollen cans, and 5 swollen control cans (nondented). The third group had 10 dented swollen cans and 5 swollen control cans. Of 600 cans analyzed, 37 (6.2%) were deleted from the analysis because results were not available for both tests. One laboratory was constrained by scheduling to analyze 15 of 45 swollen cans. The helium leak test found 12 (13%) positives of 92 nondented swollen cans. One pressurization test yielded 7 of those 12 positives. Of the 400 dented cans sent as possible leakers, the helium test found 267 positives, and the vacuum test found 181. Five of the 7 analysts had significantly (alpha = 0.05) higher percent positive helium results. One analyst found more leakers by the vacuum leak test. Both tests found fewer positives in the swollen dented cans than in the flat dented cans. After exposure to pressurized helium, all cans with greater than 8 psi headspace pressure were positive helium leakers. The method was adopted official first action.

Foodborne enterotoxigenic Escherichia coli: detection and enumeration by DNA colony hybridization.

Four methods were compared for detecting heat-labile toxin production by Escherichia coli: DNA colony hybridization, two enzyme-linked immunosorbent assays, and the mouse Y-1 adrenal cell reaction. Although results of the methods were in general agreement, there were some differences in specificity and sensitivity. DNA colony hybridization was used to detect and enumerate enterotoxigenic E. coli isolates in artificially contaminated food without enrichment. Sensitivity level was 100 cells per g.

Perkinsus marinus extracellular protease modulates survival of Vibrio vulnificus in Eastern oyster (Crassostrea virginica) hemocytes.

The in vitro effects of the Perkinsus marinus serine protease on the intracellular survival of Vibrio vulnificus in oyster hemocytes were examined by using a time-course gentamicin internalization assay. Results showed that protease-treated hemocytes were initially slower to internalize V. vulnificus than untreated hemocytes. After 1 h, the elimination of V. vulnificus by treated hemocytes was significantly suppressed compared with hemocytes infected with invasive and noninvasive controls. Our data suggest that the serine protease produced by P. marinus suppresses the vibriocidal activity of oyster hemocytes to effectively eliminate V. vulnificus, potentially leading to conditions favoring higher numbers of vibrios in oyster tissues.