Analysis of the activity of promoters from two photosynthesis-related genes psaF and petH of spinach in a monocot plant, rice

The subunit III of photosystem I and ferredoxin-NADP(+)-oxidoreductase are encoded by nuclear genes, namely psaF and petH. The activity of their promoters from spinach has been evaluated in transgenic tobacco earlier. Evaluation of the activity of these Dicotyledoneae-specific promoters has been carried out in a monocot system (i.e. rice) by transient gene expression system, based on electroporation-mediated gene delivery into protoplasts from leaves and roots. It has been found that various promoter deletions show higher activity in leaf protoplasts and elements for quantitative response are widely distributed. Transgenic rice has also been produced with a petH promoter and gus reporter gene construct. Although petH promoter is a weak promoter in comparison to the 35S promoter, it expresses well in green tissues and could be useful for plant genetic engineering.

Case-control study of Meige's syndrome. Result of a pilot study

A pilot case-control study was conducted to identify possible risk factors for Meige's syndrome. Patients with Meige's syndrome and age- and sex-matched controls suffering from other neurological diseases were recruited from the Movement Disorders Clinic and Neurology Outpatient Department of the All India Insititute of Medical Sciences. All participants were interviewed and information regarding psychiatric and medical illnesses, use of medications, exposure to fumes, dust and pets, characteristics such as marital status, socio-economic status, alcohol, tea/coffee use, tobacco use, betel nut chewing and family history of neurodegenerative diseases among first-degree relatives was ascertained. We found that betel nut with tobacco chewing was a significant predictor for Meige's syndrome (adjusted odds ratio 7.4, 95% confidence interval = 1.0-59. 82). The role of local irritation or the effect of some chemicals in tobacco and betel nuts needs further evaluation of the pathogenesis of Meige's syndrome.

Effect of preservation techniques and food additives on staphylococcal thermonuclease

Staphylococcal TNase was found to retain its activity fully even after exposure to chilling and refrigeration temperatures for 24 h. It was not inhibited by p-hydroxy benzoic acid, sorbic acid, methylpropyl p-benzoic acid and sodium nitrite in the concentration range of 0.04 to 0.5%, whereas it was inhibited by 100 ppm of butylated hydroxy anisole (BHA), 200 ppm of butylated hydroxy toluene (BHT), and 300 ppm of propyl gallate. There was not complete inhibition of S. aureus and TNase by tocopherol (TP) and ascorbic acid (AA) even at concentration of 300 ppm. These results indicate that TNase can be used as an index of potentially enterotoxin producing S. aureus contamination in foods subjected to chilling, refrigeration as well as in foods containing common preservatives and antioxidants.

Pathological lesions in lambs fed raw or processed cottonseed meal

Thirty male lambs of 3-4 months of age, were assigned equally to five dietary treatments in a completely randomized design and fed isonitrogenous and isocaloric concentrate mixtures containing 30% de-oiled peanut meal (DPNM) or 40%, cottonseed meal, which was raw, cooked for 45 min or treated with either 1%, calcium hydroxide or iron (1:3, free gossypol: Fe). The mixtures containing raw or variously processed CSM replaced about 50% of the nitrogen of the reference concentrate mixture. These concentrate mixtures were fed to meet 80% of the animals' crude protein requirements along with ad libitum feeding of maize (Zea mays) hay for 180 days. The free gossypol content of the raw cottonseed meal (0.27%) was reduced to 0.16% 0.20% and 0.21% by the cooking, Ca(OH)2 and iron treatments, respectively. At the end of the experiment, the tissues of various organs were fixed in 10% formol saline. embedded in paraffin and sectioned at 4-5 microm thickness, and duplicate sections were stained with either haematoxylin and eosin or Perl's Prussian blue. The lambs fed diets incorporating raw, cooked, Ca(OH)2- or iron-treated cottonseed meal consumed respectively 302, 215, 250 and 222 mg free gossypol/day. No morbidity. mortality or gross lesions were observed in any organs and the histopathological lesions due to cottonseed meal were limited to the testes and epididymis. Spermatogonial cells were absent in the majority of the seminiferous tubules of testes from lambs fed raw cottonseed meal. Most seminiferous tubules were collapsed, with a reduced wall thickness, owing to there being fewer germ cell layers and vacuolation of the basal cells. The epithelium of the epididymal ductules was degenerated, desquamated to a variable degree with hyperplastic changes, and they were devoid of spermatozoa. Most lambs fed any of the processed cottonseed meals did not show any of these lesions, and such lesions as occurred in affected lambs in these groups were relatively mild. Iron pigments were deposited around the portal areas of the liver, the tip of intestinal villi and the spleen of lambs fed the iron-treated cottonseed meal diet. Cooking or treatment with 1%, Ca(OH)2 effectively minimized the toxic effects of free gossypol.

Need for bringing in a change in biochemistry curriculum to make it clinically oriented?

OBJECTIVES

This study was conducted to (a) assess the views of medical students and doctors regarding relevance of biochemistry training, (b) explore if they have any suggestion to bring in any improvement in contents of biochemistry curriculum and mode of teaching.

METHODS

In 1997-98, a structured questionnaire was filled up by 114 medical students and 118 doctors.

RESULTS

As many as 62/114 (55%) medical students and 40/118 (34%) doctors believed that it is not important to remember minute details of biochemical reactions (p value < 0.0001). Among medical students, 108/110 (98.2%) agree that a clinician should be invited to seminars for developing skills of interpretation of laboratory investigations; whilst 110/118 (93.2%) doctors expressed similar view, p value ns. Approximately 92% responders favored that departments biochemistry and physiology should co-ordinate on the topics of common interest in order to save time and effort. What is the most informative and effective way of teaching biochemistry?' in response to this question only 0.9% responders opted lecture as the best option. Seminars with active participation of medical students was preferred by 93.2% responders. About 6.9% responders reckoned that symposium prepared by a more than one teacher. In response to the question whether it is possible to cover pre-clinical subjects in 12 months so as to allow spiral mode of curriculum, 73% of all the responders agreed that it would be good idea, there was no difference of opinion among the doctors and medical students. On the other hand, 27% were strongly opposed to this suggestion.

CONCLUSIONS

We suggest that there is a need to modify the contents, methods of teaching, and curriculum organization of training in clinical biochemistry. How best the curriculum can be made problem oriented needs to be debated among medical educationists.

Reliability of measurements of muscle tone and muscle power in stroke patients

OBJECTIVES

to establish the reliability of the modified Ashworth scale for measuring muscle tone in a range of muscle groups (elbow, wrist, knee and ankle; flexors and extensors) and of the Medical Research Council scale for measuring muscle power in the same muscle groups and their direct antagonists.

DESIGN

a cross-sectional study involving repeated measures by two raters. We estimated reliability using the kappa statistic with quadratic weights (Kw).

SETTING

an acute stroke ward, a stroke rehabilitation unit and a continuing care facility.

SUBJECTS

people admitted to hospital with an acute stroke-35 patients, median age 73 (interquartile range 65-80), 20 men and 15 women.

RESULTS

inter- and intra-rater agreement for the measurement of power was good to very good for all tested muscle groups (Kw = 0.84-0.96, Kw = 0.70-0.96). Inter- and intra-rater agreement for the measurement of tone in the elbow, wrist and knee flexors was good to very good (Kw = 0.73-0.96, Kw = 0.77-0.94). Inter- and intra-rater agreement for the measurement of tone in the ankle plantarflexors was moderate to good (Kw = 0.45-0.51, Kw = 0.59-0.64).

CONCLUSIONS

the Medical Research Council scale was reliable in the tested muscle groups. The modified Ashworth scale demonstrated reliability in all tested muscle groups except the ankle plantarflexors. If reliable measurement of tone at the ankle is required for a specific purpose (e.g. to measure the effect of therapeutic intervention), further work will be necessary.

Molecular mechanisms of target recognition in an innate immune system: interactions among factor H, C3b, and target in the alternative pathway of human complement

In the alternative pathway of complement (APC) factor H is the primary control factor involved in discrimination between potential pathogens. The APC deposits C3b on possible Ags, and the interaction with factor H determines whether the initial C3b activates the APC. Factor H is composed of a linear array of 20 homologous short consensus repeats (SCR) domains with many functional sites. Three of these sites are involved in binding C3b and regulating complement activation; others bind to sialic acid and/or heparin and are responsible for host recognition. Using site-directed mutations we have examined the contributions of each of these sites to target discrimination and to functional activities of factor H. Decay acceleration by SCR1-4 of C3/C5 convertases bound to nonactivators was strongly dependent on SCR domains 11-15 and 16-20. Loss of these regions caused a 97% loss of activity, with SCR16-20 being the most critical (>90% loss). On APC activators the pattern of site usage was different and unique on each. On yeast, deletion of the 10 C-terminal domains (SCR11-20) had no effect on specific activity. On rabbit erythrocytes, this deletion caused loss of 75% of the specific activity. An examination of binding affinity to C3b on the four cell types demonstrated that factor H exhibits a unique pattern of SCR involvement on each cell. The results reveal a complex molecular mechanism of discrimination between microbes and host in this ancient innate defense system and help explain the different rates and intensities of APC activation on different biological particles.

Modulation of xenobiotic metabolism and oxidative stress in chronic streptozotocin-induced diabetic rats fed with Momordica charantia fruit extract

We studied the long-term effects of streptozotocin-induced diabetes on tissue-specific cytochrome P450 (CYP) and glutathione-dependent (GSH-dependent) xenobiotic metabolism in rats. In addition, we also studied the effect of antidiabetic Momordica charantia (karela) fruit-extract feeding on the modulation of xenobiotic metabolism and oxidative stress in rats with diabetes. Our results have indicated an increase (35-50%) in CYP4A-dependent lauric acid hydroxylation in liver, kidney, and brain of diabetic rats. About a two-fold increase in CYP2E-dependent hepatic aniline hydroxylation and a 90-100% increase in CYP1A-dependent ethoxycoumarin-O-deethylase activities in kidney and brain were also observed. A significant increase (80%) in aminopyrene N-demethylase activity was observed only in rat kidney, and a decrease was observed in the liver and brain of diabetic rats. A significant increase (77%) in NADPH-dependent lipid peroxidation (LPO) in kidney of diabetic rats was also observed. On the other hand, a decrease in hepatic LPO was seen during chronic diabetes. During diabetes an increased expression of CYP1A1, CYP2E1, and CYP4A1 isoenzymes was also seen by Western blot analysis. Karela-juice feeding modulates the enzyme expression and catalytic activities in a tissue- and isoenzyme-specific manner. A marked decrease (65%) in hepatic GSH content and glutathione S-transferase (GST) activity and an increase (about two-fold) in brain GSH and GST activity was observed in diabetic rats. On the other hand, renal GST was markedly reduced, and GSH content was moderately higher than that of control rats. Western blot analyses using specific antibodies have confirmed the tissue-specific alterations in the expression of GST isoenzymes. Karela-juice feeding, in general, reversed the effect of chronic diabetes on the modulation of both P450-dependent monooxygenase activities and GSH-dependent oxidative stress related LPO and GST activities. These results have suggested that the modulation of xenobiotic metabolism and oxidative stress in various tissues may be related to altered metabolism of endogenous substrates and hormonal status during diabetes. The findings may have significant implications in elucidating the therapeutic use of antidiabetic drugs and management of Type 1 diabetes in chronic diabetic patients.

Haemodynamic effects of pan masala in healthy volunteers

OBJECTIVES

We studied acute haemodynamic effects of pan masala (powdered mixture of areca nut, slaked lime, catechu, and condiments) in healthy volunteers.

METHODS

Fifty one males (mean age 28.6 +/- 10 years) were evaluated. One pouch (4 g) of pan masala without tobacco was given to each subject under fasting state and effects on pulse and blood pressure (BP) recorded.

RESULTS

At baseline the pulse rate was 75.1 +/- 9.0 per minute, systolic BP was 119.1 +/- 10.8 mm Hg, and diastolic BP was 78.0 +/- 7.5. The pulse rate increased to 87.5 +/- 11.4 at ten minutes (+16.9 +/- 12.6%, p < 0.001) and fell to 76.7 +/- 9.1 at 30 minutes (p = ns). Systolic BP increased to 122.3 +/- 11.7 mm Hg at 10 minutes (+2.73 +/- 5.1%, p < 0.001) and was 120.8 +/- 10.8 at 30 minutes; while diastolic BP was 80.8 +/- 7.3 at 10 minutes (+3.83 +/- 6.1%, p < 0.001) and 79.4 +/- 7.6 at 30 minutes.

CONCLUSIONS

Pan masala intake causes acute increase in pulse and BP.

Study in sexuality of medical college students in India

PURPOSE

In India, talking about sex is taboo. Little is known about the knowledge, attitude, and sexual behavior of adolescents. This study was carried out with the purpose of examining: (a) the knowledge of medical students about sex, (b) the sources of learning about sex, and (c) the sexual behavior and practices of young adults.

METHODS

This study was carried out among the undergraduate students of a medical college in Delhi. A pretested, semiclosed-type questionnaire was voluntarily filled out by the students. Confidentiality and secrecy was assured.

RESULTS

Of 500 students, 73% participated in the study. Knowledge regarding sexual intercourse, masturbation, contraception, and sexually transmitted diseases was satisfactory among 70%, 74.8%, 83.5%, and 92.6% of the respondents, respectively. Common source of knowledge about sex were friends (74.5%), pornographic films (56.2%), and books and magazines (55.1%). Only one fifth could communicate with teachers, parents, and persons of the other gender about sex. About 417 of the students viewed homosexuality as normal behavior. Sexual intercourse had been experienced by 11.8% of respondents. The mean age of first sexual intercourse was 17.5 years. Eighty-five percent strongly favored introduction of sex education at school level.

CONCLUSION

Evidence is provided for the need to improve knowledge about different aspects of sex among a sample of Indian medical students.

Effective therapy for severe Henoch-Schonlein purpura nephritis with prednisone and azathioprine: a clinical and histopathologic study

OBJECTIVES

To validate a scoring system to assess the severity of renal lesions and to correlate histology with clinical findings. We also examined the efficacy of treatment with prednisone (1 to 2 mg/kg/d) and azathioprine (1 to 2 mg/kg/d) for severe Henoch-Schonlein purpura (HSP) nephritis.

METHODS

Twenty patients were evaluated retrospectively. All underwent biopsy before treatment, and 13 underwent biopsy after therapy. We developed a scale based on glomerular, tubulointerstitial (TI), and vascular changes and assigned all specimens acuity, chronicity, and TI scores. The outcomes of 17 patients were compared with those of a historical control group.

RESULTS

Chronicity score at initial biopsy increased with increasing delay between onset of renal involvement and first biopsy (rho = 0.55, P =.016) but did not progress after treatment was initiated. Both acuity (rho = 0.57,P =. 016) and TI (rho = 0.69, P =.003) scores correlated with clinical severity at first biopsy. The TI score correlated negatively with serum albumin (rho = -.60, P <.01). Significantly more patients in the study group than in the control group had a favorable outcome (15 [88%] of 17 vs 32 [54%] of 59, P =.011).

CONCLUSIONS

Our scale reflects disease activity and highlights the importance of TI changes in severe HSP nephritis. Outcome comparisons indicate that early treatment with prednisone and azathioprine prevents progression of chronic changes and improves outcome.

Comparison of the Humphrey swedish interactive thresholding algorithm (SITA) and full threshold strategies

PURPOSE

To compare the Swedish interactive thresholding algorithm (SITA) strategy with the full threshold strategy in routine clinical practice.

METHODS

Using the Humphrey visual field analyzer model 750 (Allergan Humphrey, San Leandro, CA), 108 subjects were tested with 24-2 SITA (version A9) and 24-2 full threshold strategies. Test results were compared for time taken and reliability and on the basis of seven criteria of abnormality.

RESULTS

The SITA required on average 48.8% less time than the full threshold strategy. Patient reliability parameters were somewhat better with SITA. There was a strong correlation between mean deviation and pattern standard deviation. Average threshold sensitivity at each point was increased by 1.31 dB with SITA, but greater differences were seen at points with lower sensitivity. Using the full threshold strategy as our standard for comparison, the sensitivity of SITA varied from 83.0% to 93.2% in detecting the variously defined abnormalities. Fields shown as normal with full threshold strategy corresponded with those found to be normal with SITA in 79.0 to 96.3% cases depending on criteria for abnormality. There were a few cases in which SITA suggested an early abnormality but results of full threshold testing remained normal. On average, the size and depth of scotomas decreased slightly with SITA, but this difference was not statistically significant. Of the 70 patients surveyed about their preference, 65 (92.9%) preferred SITA.

CONCLUSION

Full threshold and SITA strategies are comparable in detecting glaucomatous defects. The SITA strategy requires significantly less time to perform and is a satisfactory alternative to full threshold algorithms in clinical practice for diagnosis and management of glaucoma.

Myasthenia gravis and recurrent falls in an elderly patient

PRESENTATION

An elderly man had recurrent hospital admissions with falls.

OUTCOME

Acetylcholine receptor antibodies and single-fibre electromyogram were useful in the diagnosis of myasthenia gravis. Treatment prevented further hospital admissions.

Association of Helicobacter pylori with peptic perforation in Chattisgarh region of India

BACKGROUND

Helicobacter pylori is present in over 90% cases of peptic ulcer. There are very few reports regarding prevalence of H. pylori infection in peptic ulcer perforation which is the commonest complication of peptic ulcer disease. In the present study we have drawn this association.

PATIENTS AND METHODS

44 cases of peptic perforation were included in this study. Per-operative biopsy was taken from the margin of perforation. The criteria for H. pylori positivity were, Positive Rapid Urease Test and evidence of H. pylori infection on histological examination using Modified Giemsa and H&E stains.

RESULTS

Prevalence of H. pylori infection in peptic perforation was 61.4%. This is well above the usual prevalence in normal population of 45%. H. pylori infection was significantly more common in cases of chronic dyspepsia (> 6 months) and not significantly related to sex, blood group, addiction, family history of acid peptic disease and previous H2 blocker therapy.

INFERENCE

H. pylori is found more commonly in patients with peptic ulcer perforation than in those without.

Effect of gamma irradiation on staphylococcal thermonuclease (TNase)

Stability of staphylococcal thermonuclease (TNase) on exposure to irradiation though expected has not been experimentally established. In the present work. TNase in presence of standard growth media as well as dairy and meat products was found to be completely resistant even at a dose of 10 kGy indicating that the TNase can be used as an indicator of Staphylococcal aureus contamination even in foods in which S. aureus have been destroyed by irradiation. This new application of TNase is being reported for the first time.

Trichotillomania and trichophagia leading to trichobezoar

A 14-year-old female presented with the complaints of loss of hair, scalp pruritus, and pain in the abdomen. On careful work-up, she was found to have trichotillomania as well as trichophagia. Investigations also revealed a trichobezoar which completely filled the stomach. Hemogram showed moderate hypochromic anemia. Her detailed psychiatric profile showed a few additional features like obsessive hand washing, knuckle cracking, nose picking and body rocking. Her trichobezoar was removed surgically, and she had an uneventful post-operative recovery. She is being maintained on fluoxetine and is doing well. The role of a multi-disciplinary approach to trichotillomania patients is highlighted.

Congenital urethral fistula

A case of congenital urethral fistula with an intact glanular urethra without chordee is reported with a discussion of the possible etiology and one-stage repair.