An outbreak of food poisoning in a military establishment

Background: An outbreak of food poisoning in a military establishment mess was investigated and remedial measures suggested.     

Tyrosine phosphorylation-dependent inhibition of hippocampal synaptic plasticity

We examined the effects of two protein tyrosine phosphatase inhibitors on the induction of synaptic plasticity in CA1 slices of rat hippocampus. Field potential recordings were made in stratum radiatum in response to stimulation of the Schaffer collateral afferents. Bath application of the tyrosine phosphatase inhibitors sodium orthovanadate or phenylarsine oxide for 30 min had little effect on basal synaptic transmission but blocked the induction of both long-term potentiation (LTP) and homosynaptic long-term depression (LTD). LTP could be partially recovered, and LTD fully recovered, when conditioning stimulation was given in conditions of reduced synaptic inhibition. The block of both forms of synaptic plasticity by the phosphatase inhibitors correlated with a concurrent depression of the N-methyl-D-aspartate (NMDA) receptor-mediated potential, as measured both extracellularly and intracellularly. This depression, which was also induced by peroxyvanadate, required synaptic stimulation to be induced, and was tyrosine kinase-dependent. Our results suggest that tyrosine phosphorylation of as yet unidentified proteins is responsible for a novel activity-dependent depression of NMDA receptor function that inhibits synaptic plasticity.     

TRACHEOSTOMY COMPLICATIONS AND THEIR MANAGEMENT

The word tracheostomy derived from two greek words meaning ‘I cut the trachea’ has been known for about 3500 yrs. The process has evolved over the years and has undergone revolutionary changes in the methodology, instrumentation and indications. Although tracheostomy is now commonly used the complication rate remains high. In our series it was 48% which is comparable with other series. The purpose of this paper is to discuss the complications of tracheostomy with special attention to their management and prevention.KEY WORDS: Complications, Tracheostomy     

Inhibition of platelet function by contrast media: iopamidol and ioxaglate versus iothalamate. Work in progress

The effects of an ionic contrast agent, meglumine iothalamate (Conray-60), and two newer low-osmolality radiographic contrast media, sodium meglumine ioxaglate (Hexabrix) and iopamidol (B-15,000), on platelet aggregation and secretion responses were studied. All three agents inhibited platelet responses during stimulation with adenosine diphosphate (ADP), epinephrine, and collagen. Platelet function was inhibited by iothalamate at concentrations of 11 mg iodine/ml and above, and by the newer agents at concentrations above 30 mg iodine/ml. Addition of exogenous calcium decreased the iothalamate-induced inhibition of aggregation but did not improve dense granule secretion. There was no consistent effect of exogenous calcium on platelet inhibition by iopamidol and ioxaglate. These studies indicate that the newer agents inhibit platelet function less than iothalamate does, and that chelation of Ca2+ may not be the major mechanism of platelet inhibition by contrast agents.     

Does prophylactic sotalol and magnesium decrease the incidence of atrial fibrillation following coronary artery bypass surgery: a propensity-matched analysis

Background  

Atrial fibrillation can occur in up to 40% of patients undergoing coronary surgery.     

Bencyclane as an anti-sickling agent

A vasodilating Ca²⁺ channel blocker, bencyclane, was used in 18 patients with homozygous sickle cell anaemia (SCD) to test the possible anti-sickling effect. With bencylane intervention the Na⁺-K⁺ ATPase activity increased from 256±29 to 331±37 nmol Pi/mg protein/h ( P <0.0001) and the Ca²⁺-Mg²⁺ ATPase level increased from 172±12 to 222±44 nmol Pi/mg protein/h ( P <0.0001). The intracytoplasmic Ca²⁺ concentration reduced from 3.5±0.6 to 2.7±0.25 μmol/l ( P <0.0001). The patient's blood contained fewer irreversibly sickled cells (ISCs) (a reduction from 21.4% to 14.4%) ( P <0.05). At the same time MCHC of the erythrocytes decreased from 34.5 to 33.0 g/dl ( P <0.05). Bencyclane appears to be a promising anti-sickling agent that can be used orally in SCD.     

The pronase resistance of cholesterol-nucleating glycoproteins in human bile

BACKGROUND & AIMS: Many putative pronucleating proteins have been isolated from the biliary concanavalin A (con A)-binding fraction. The pronase resistance of the overall nucleating-promoting activity was almost never taken into consideration. The aim of this study was to identify the major pronase-resistant con A-binding glycoproteins. METHODS: Pronase-treated and -untreated con A-binding glycoproteins were separated on a Superose 12 gel permeation column (Pharmacia, Uppsala, Sweden) and tested in a crystal growth assay. Proteins were identified by amino-terminal sequencing. RESULTS: Con A-binding pronucleating activity eluted in two peaks on the Superose column. This activity was unaltered after pronase treatment. Activity peak I contained too little protein to allow amino-terminal sequencing. In activity peak II, the major pronase-resistant con A-binding glycoproteins were identified as alpha 1-antitrypsin and alpha 1- antichymotrypsin. The 130-kilodalton nucleation promoter was identified as aminopeptidase N, but the full pronase resistance of this protein, reported earlier, was not confirmed. Immunoabsorptive removal of alpha 1-antitrypsin and alpha 1-antichymotrypsin and immunopurification showed that only alpha 1-antichymotrypsin had pronucleating activity. CONCLUSIONS: The pronase resistance of the nucleating-promoting activity of the con A-binding glycoprotein fraction was confirmed. An important part of this activity could be attributed to alpha 1- antichymotrypsin. It is an acute-phase protein, as are many other pronucleating proteins, which might indicate a general mechanism of action in gallstone formation. (Gastroenterology 1996 Jun;110(6):1926-35)     

Evaluation of Vitreous Substitutes in Managing Complicated Vitreo-retinal Surgeries

Background

Vitreous substitutes presently in use for intraoperative tamponade are perfluorocarbon liquids (PFCL) and for post operative tamponade are silicon oil (SO), sulphur hexafluoride (SF₆) and perfluorocarbon gas (PFC). Several factors are important for a thorough understanding of each of these vitreous substitutes. The absorption or necessity for removal, indications for use (including clinical studies and special surgical methods), additives and complications of use have to be considered.

Methods

Three port standard pars plana vitrectomy was performed in 60 consecutive cases requiring intra-vitreal intervention. PFCL was used intra-operatively in 30 cases (PFCL group and X group). The eyes were implanted with SO (silicon oil subgroup), PFC (C₃F₈ sub-group) and SF₆ (SF₆ sub-group) in twenty cases each. Apart from best corrected visual acuity (BCVA), the retinal status and the longevity of gas when used, changes and reaction in both the anterior and posterior segments were noted.

Result

The difference of postoperative BCVA in the PFCL and non-PFCL groups was statistically significant with p < 0.001. In both the PFCL and non-PFCL groups the difference between preoperative and postoperative BCVA was statistically significant with p < 0.0001. All three vitreous substitutes studied are effective given the case where they had been utilised.

Conclusion

PFCL is invaluable in the management of complicated retinal detachment (RD). Where a vitreous microsurgery is indicated, the visual outcome is good. SF₆ is useful for short-term tamponade. Silicon oil and C₃F₈ are useful for longer tamponade.Key Words: Tamponade, Perfluorocarbon liquids, Silicon oil, Sulphur hexafluoride, Perfluorocarbon gas, Retinal detachment     

Measuring domestic violence in human immunodeficiency virus-positive women

Background

Violence affects the lives of millions of women worldwide, in all socioeconomic classes. Violence and the fear of violence are emerging as important risk factor contributing to the vulnerability to human immunodeficiency virus (HIV) infection for women. The objective of the present cross sectional study is to compare the experiences of domestic violence between HIV-positive and HIV-negative married women seeking treatment in a tertiary care hospital.

Methods

The study is conducted in a tertiary care hospital in Pune on a randomly selected 150 married women (75 HIV-positive and 75 HIV-negative). Informed consent was obtained from all the women and also a trained counsellor was present during the process of data collection. The data was collected by interview method by taking precautions as laid down in the World Health Organization's ethical and safety recommendations for research on domestic violence and using modified conflict tactics scale (CTS). The definition of violence followed is as per the Declaration on the Elimination of Violence against Women, adopted by the United Nations General Assembly in 1993.

Results

The percentage of women reporting domestic violence is 44.7% (95% confidence interval [CI] = 36.84–52.68). The proportion of physical, emotional and sexual violence reported is 38% (95% CI = 30.49–45.96), 24% (95% CI = 17.67–31.31), and 14.7% (95% CI = 9.66–21.02), respectively. The odds of reporting violence of all forms is significantly higher among HIV-positive women than among HIV-negative women (P<0.05). Univariate and multivariate logistic regression is carried out to examine the possible predictors of domestic violence.

Conclusion

The findings suggest high proportion of HIV-positive women report violence then HIV-negative women which must be addressed through multilevel prevention approaches.