Reassessing hemodialysis adequacy in children: the case for more

Several lines of evidence support an upward revision in pediatric hemodialysis dose guidelines: Although current recommendations are derived largely from studies of dialysis mortality and morbidity in adults, recent reports of improved growth and pubertal development with more intensive dialysis highlight the need for appropriate pediatric outcome measures in the assessment of dialysis adequacy, particularly in prepubertal patients. Even if adult studies can be extrapolated directly to younger patients, reappraisal of these data would appear to justify an increase in recommended dialysis clearances, based on higher dietary protein intake and accumulating evidence that adults, too, benefit from more intensive therapy. Suboptimal dialysis may also occur when dialysis dose is overestimated by urea kinetic models that fail to account for compartment effects and post-treatment urea rebound. Studies comparing the available models in pediatric patients have appeared recently, and a few models have been developed specifically for pediatric applications. These should permit more reliable estimates of solute clearance for a much-needed multicenter trial to clarify optimal dialysis therapy for growing children.

Effect of alpha-tocopherol supplementation on the ultrastructural abnormalities of peripheral nerves in experimental diabetes

Ultrastructural observations were made on myelinated fibers in the tibial nerves in order to investigate the beneficial effects of alpha-tocopherol administration in streptozotocin-diabetic rats. Male Wistar rats, aged 12 weeks and weighing between 250 g to 300 g were studied. Six onset control rats were used to obtain the baseline parameters for this strain and age. Further 3 groups--untreated diabetic animals, diabetic animals treated with alpha-tocopherol, and age-matched controls--were studied over a 3-month period. In the diabetic animal, administration of alpha-tocopherol resulted in a significant increase (p < 0.05) in total plasma vitamin E levels when compared with other groups. Myelinated fiber cross-sectional area (p < 0.05), axonal area (p < 0.01) and myelin sheath area (p < 0.05) were significantly less in the tibial nerve of diabetic animals than in age-matched controls, but not different from those of onset controls. In the alpha-tocopherol treated diabetic animals, the values for these parameters were intermediate without showing significant difference when compared with age-matched controls and untreated diabetics. The "g" ratio (axon to fiber area) did not differ between any experimental groups. The number of large myelinated fibers were less in the untreated diabetic animals, but in the alpha-tocopherol-treated diabetics, the values were significantly higher (p < 0.05) than with untreated diabetics and were similar to those of age-matched controls. In conclusion, this ultrastructural study reiterated the fact that structural abnormalities of myelinated fibers occur in experimental diabetes and that alpha-tocopherol administration may be useful in preventing the development of these abnormalities.

Benzyl ester prodrug of ibuprofen: pharmacological and toxicological profile

Prodrug approach is a promising way of overcoming gastrotoxicity associated with long term oral use of NSAIDs like ibuprofen. The candidature of benzyl ester prodrug of ibuprofen was examined to assess its ability to reduce gastrotoxicity without affecting pharmacological response. It gave highly promising activity profile in established animal models like carrageenan induced rat paw oedema and acetic acid induced writhing reflex assay. The effect of physicochemical properties like aqueous solubility, octanol-water partition coefficient, hydrolysis kinetics in human plasma and simulated gastric fluid, on activity profile has been investigated.

Tolerability and pharmacokinetics of the nitrone NXY-059 in patients with acute stroke

BACKGROUND AND PURPOSE

Increased free radical formation contributes to the damage caused to the brain by acute ischemia. NXY-059 is a nitrone-based free radical trapping agent in development for acute stroke. NXY-059 has neuroprotective efficacy when given 5 hours after onset of transient focal ischemia in the rat.

METHODS

This was a randomized, double-blind, placebo-controlled, parallel group, multicenter study that evaluated the safety and tolerability of 2 NXY-059 dosing regimens compared with placebo within 24 hours of acute stroke. NXY-059 was administered as either 250 mg over 1 hour followed by 85 mg/h for 71 hours or 500 mg over 1 hour followed by 170 mg/h for 71 hours; plasma concentrations were monitored. Neurological and functional outcomes were recorded up to 30 days.

RESULTS

One hundred fifty patients were recruited, of whom 147 received study treatments and completed assessments (50 placebo, 48 lower-dose NXY-059, 49 higher-dose NXY-059). Mean (+/-SD) age was 68 (+/-10) years, and baseline National Institutes of Health Stroke Scale score was 7.9 (+/-6.2). Serious adverse events occurred in 16%, 23%, and 16% of patients, respectively, with deaths in 0%, 10%, and 4%, largely following the proportions with primary intracerebral hemorrhage (6%, 16%, and 8%). Hyperglycemia, headache, and fever were common but not related to treatment. The mean unbound steady state NXY-059 plasma concentrations were 25 and 45 micromol/L, respectively. Population pharmacokinetic analysis estimated clearance to be 4.6 L/h.

CONCLUSIONS

NXY-059 was well tolerated in patients with an acute stroke. The testing of higher doses in future trials may be justified.

Surgical emphysema--an unusual finding in spontaneous neonatal gastric perforation

A neonate presented with extensive surgical emphysema of the abdominal wall and a spontaneous gastric perforation. This clinical presentation is very rare. Early diagnosis and treatment improve the clinical outcome.

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.