Alkyl ester prodrugs for improved topical delivery of ibuprofen

Topical delivery of ibuprofen directly to the site of inflammation can overcome gastrointestinal side effects associated with its long term oral administration. The set of physicochemical properties necessary for optimum topical delivery of ibuprofen can be imparted by formation of its ester prodrugs. Various alkyl ester prodrugs (methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, tert-buty, n-pentyl, hexyl, heptyl, octyl, lauryl, cetyl and octadecyl esters) were synthesised and studied for their physicochemical properties and activity in the carrageenan induced rat paw oedema by topical route. Favourable shift in lipophilicity and self penetration enhancing effect of prodrugs responded in improved topical activity over the parent drug ibuprofen.

Experimental study of harmonic generation from solid surfaces irradiated by multipicosecond laser pulses

An experimental study is presented on harmonic generation from solid surfaces using 27 ps Nd:glass laser pulses (lambda=1053 nm) in the intensity range of 10(13)-10(15) W cm(-2). Second, third, and fourth harmonics emitted in the specular reflection direction showed intensity scaling exponents of 1.5, 1.8, and 3.8 for an obliquely incident p-polarized laser beam, providing a conversion efficiency of 2x10(-8), 10(-10), and 5x10(-12) at 10(15) W cm(-2), respectively. Second and third harmonic radiation generated using an s-polarized pump was about 10 and 100 times smaller, respectively, compared to that for the p-polarized laser radiation. Faraday rotation observed in the reflected fundamental radiation can explain the relative harmonic yields for the p and s polarizations of the pump beam.

The COSTAR wheelchair study: a two-centre pilot study of self-propulsion in a wheelchair in early stroke rehabilitation. Collaborative Stroke Audit and Research

OBJECTIVE

It is uncertain whether self-propulsion in a wheelchair should be encouraged or discouraged in the early stages of stroke rehabilitation.

DESIGN

A two-centre pilot study to assess the feasibility of performing a multicentre randomized controlled trial on this subject.

SETTING

Clatterbridge and Aintree Stroke Rehabilitation Units, Merseyside, UK.

SUBJECTS

Forty early stroke patients (mean age 67 years) in whom it was uncertain whether self-propulsion in a wheelchair should be encouraged were studied.

INTERVENTION

A central randomization service at Newcastle University was used to determine the policy about wheelchair provision and use for each patient. They were allocated to either an 'encouraged to self-propel' or a 'discouraged from self-propulsion group'. OUTCOME MEASURES USED: Independent outcome assessment was performed by postal questionnaire and telephone interview using the Barthel ADL Scale, Nottingham Extended ADL Scales and the shortened General Health Questionnaire (GHQ-12) at 3 and 12 months. Patient's length of stay and their Ashworth tone score were also measured either at three months or when they were discharged from hospital.

RESULTS

After considerable preparation time it was possible to conduct a trial on self-propulsion in early stroke rehabilitation in the two-pilot centres. No major differences were found between the pilot groups for any of the outcome measures.

CONCLUSIONS

A multicentre randomized controlled trial to assess this question is feasible but further work is being conducted before proceeding, to satisfy the concerns expressed to our group regarding the appropriateness of the intervention and the outcome measures.

Human CD34(+) stem cells express the hiwi gene, a human homologue of the Drosophila gene piwi

Hematopoietic stem cells (HSCs) are characterized by their dual abilities to undergo differentiation into multiple hematopoietic cell lineages or to undergo self-renewal. The molecular basis of these properties remains poorly understood. Recently the piwi gene was found in the embryonic germline stem cells (GSCs) of Drosophila melanogaster and has been shown to be important in GSC self-renewal. This study demonstrated that hiwi, a novel human homologue of piwi, is also present in human CD34(+) hematopoietic progenitor cells but not in more differentiated cell populations. Placing CD34(+) cells into culture conditions that supported differentiation and rapid exit from the stem cell compartment resulted in a loss of hiwi expression by day 5 of a 14-day culture period. Expression of the hiwi gene was detected in many developing fetal and adult tissues. By means of 5' RACE cloning methodology, a novel putative full-length hiwi complementary DNA was cloned from human CD34(+) marrow cells. At the amino acid level, the human HIWI protein was 52% homologous to the Drosophila protein. The transient expression of hiwi in the human leukemia cell line KG1 resulted in a dramatic reduction in cellular proliferation. Overexpression of hiwi led to programmed cell death of KG1 cells as demonstrated by the Annexin V assay system. These studies suggest that hiwi maybe an important negative developmental regulator, which, in part, underlies the unique biologic properties associated with hematopoietic stem and progenitor cells.

Activity profile of glycolamide ester prodrugs of ibuprofen

Glycolamide esters of ibuprofen (I), namely, unsubstituted (II), N,N dimethyl (III), and N,N diethyl (IV), were synthesized and studied for different physicochemical, pharmacological, and toxicological properties. They were comparable with I in respect of anti-inflammatory and analgesic activity but did not exhibit reduction in the ulcerogenicity on oral administration. However, all three exhibited significantly better topical activity in carrageenan-induced rat paw edema assay. In the same assay, they provided significant protection against inflammation when applied at a site remote to the inflammation site.

HARTMANN'S PROCEDURE REVISITED

Between July 1991 and June 1999 out of 176 patients undergoing colonic surgery (elective and emergency), Hartmann's procedure was performed in 63. There were 39 males and 24 females. Mean age was 43 years (range 12 to 81). To assess the utility of Hartmann's procedure the documents of all these 63 patients were retrospectively analysed. In 47 bowel continuity was reestablished. The over all mortality in first stage operation (Hartmann's procedure) was 12.7% and mortality in the second stage procedure (reestablishing bowel continuity) was nil. Complication rate was drastically less in second operation. The authors conclude that Hartmann's procedure is safe and effective while dealing with colorectal pathologies as resection and primary anastomosis is fraught with danger.

Colorectal cancer in children: case report and review of literature

Compared to adults, colorectal carcinoma is rare in children and has poorer prognosis, due to delay in diagnosis, advanced stage at presentation and aggressive natural history. We describe a case of mucinous adenocarcinoma of the rectum in a eleven year old boy and review the literature regarding colorectal cancer in children. A high index of suspicion and an early diagnosis may lead to an improvement in the dismal prognosis of this disease in children.

HIV/AIDS related knowledge, risk perception, attitude and sexual behavior of working women staying in hostels

HIV infection poses a formidable threat to women's health. Already, in India, women account for 21.3% of all AIDS cases. In metropolitan cities women living alone in hostels and having independent income, may have a liberal life style and chances of practising high risk sexual behaviour is greater. This study was conducted to assess the risks and risk perception of such women. Among eighty-nine hostel residents, AIDS awareness was 92.1%. Very few respondents had adequate knowledge about modes of transmission and methods of prevention. Risk perception was poor, however high risk behaviour was less commonly practised by this group.

Necrotising fasciitis of the breast

Necrotising fasciitis is a rare condition and to the best of our knowledge has never been reported in the breast. We report the first case in the literature of necrotising fasciitis involving the breast.

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.