Novel polymorphism in the promoter region of the human nerve growth-factor gene

We describe a novel T to C transition at position -198 from the transcription start of the human nerve growth-factor (NGF) gene. In British Caucasoid healthy control group that we have genotyped, T and C allele frequencies are 0.633 and 0.367, respectively. This polymorphism affects vitamin D receptor (VDR) binding to its motif in the NGF promoter.

Controversies on new animal models of Parkinson's disease pro and con: the rotenone model of Parkinson's disease (PD)

A general complex I deficit has been hypothesized to contribute to neurodegeneration in Parkinson's disease (PD) and all toxins used to destroy dopaminergic neurons are complex I inhibitors. With MPTP or 6-OHdopamine, this hypothesis can not be tested since these toxins selectively accumulate in the dopaminergic neurons. However with rotenone, which penetrates all cells, the hypothesis can be tested. Thus, the proof of the hypothesis is whether or not rotenone-induced neurodegeneration mimics the degenerative processes underlying PD. Low doses of rotenone (1.5 or 2.5 mg/kg in oil i.p.) were administered to Sprague Dawley rats on a daily basis. After about 20 days of treatment, signs of parkinsonism occurred and the concentrations of NO and peroxidase products rose in the brain, especially in the striatum. After 60 days of treatment, rotenone had destroyed dopaminergic neurons. Behaviourally, catalepsy was evident, a hunchback posture and reduced locomotion. Other transmitter systems were not, or much less affected. L-DOPA-methylester (10 mg/kg plus decarboxylase inhibition) potently reversed the parkinsonism in rats. Also when infused directly into the dopaminergic neurons, rotenone produced parkinsonism which was antagonized by L-DOPA. Some peripheral symptoms of PD are mimiced by rotenone too, for example a low testosterone concentration in the serum and a loss of dopaminergic amacrine cells in the retina. These results support the hypothesis of an involvement of complex I in PD and render the rotenone model as a suitable experimental model. The slow onset of degeneration make it suitable also to study neuroprotective strategies. Evidence that rotenone-induced neurodegeneration spreads beyond the dopaminergic system is not contradictory given that, according to the new staging studies, also degeneration in PD is not confined to dopamine neurons.

Mitochondrial complex I inhibition depletes plasma testosterone in the rotenone model of Parkinson's disease

Age-related depletion of testosterone may increase the brain's vulnerability to parkinsonian- or Alzheimer's-like neurodegenerative disorders. In rats, rotenone, a mitochondrial complex I inhibitor, causes specific nigral dopaminergic neurodegeneration producing parkinsonian symptoms. In this study, rotenone was administered on a daily basis (2 mg/kg i.p.) to two groups of rats, over a period of 30 and 60 days, respectively. In order to contribute towards the validation of the rotenone rat model, the changing level of the peripheral sex steroid hormone, testosterone, which would also mimic those found in Parkinson's disease (PD) patients, was evaluated. Parallel to this, prolactin, luteinizing hormone (LH), the nonsexual steroid thyroid-stimulating hormone, and the corticosterone hormone levels in the peripheral blood plasma were measured to show whether other hormones have also been affected by complex I inhibition. The rotenone treatment caused a decrease of testosterone level in the peripheral blood plasma. There were no differences in the thyroid hormone and prolactin but increases in leutinizing hormone and corticosterone were observed. Data from this study indicate that rotenone depleted the sex steroid hormone which is preferentially produced in the periphery, e.g., adrenal gland and testis. In conclusion, because a decrease in testosterone levels is also one of the comorbidities which are found in male PD patients, our results indicate that the rotenone model mimics PD symptoms not only on a neuronal and behavioral level, but also on the testosterone levels.

Clinical Use of RESTYLANE

There is no ideal filler, nor will there be a single product that can satisfy all requirements. However, RESTYLANE, a non-animal, stabilized hyaluronic acid (NASHA, Medicis), is a very versatile augmenting agent. It has been in clinical use for 8 years and experience has shown it to be close to the ideal filler in many respects. This review will outline the background to the use of RESTYLANE, and will focus on the clinical use of this material.

Treatment of photoaging with topical aminolevulinic acid and light

Photodynamic therapy (PDT) has been used for several years for the treatment of actinic keratoses and prevention of invasive nonmelanoma cancers. More recently, increasing physician expertise with the topical sensitizers and light sources employed in PDT has led to expanded applications, including its use for improvement of the visible signs of photoaging. Aesthetic treatment of photoaged skin with brief application of topical 5-aminolevulinic acid followed by well-tolerated light sources, such as intense pulsed light or pulsed-dye laser, can enhance the effectiveness of nonablative laser treatment without increasing adverse effects or downtime.

The Hawaiian Archipelago: a microbial diversity hotspot

The Hawaiian Archipelago is a "biodiversity hotspot" where significant endemism among eukaryotes has evolved through geographic isolation and local topography. To address the absence of corresponding region-wide data on Hawaii's microbiota, we compiled the first 16S SSU rDNA clone libraries and cultivated bacteria from five Hawaiian lakes, an anchialine pool, and the Lō'ihi submarine volcano. These sites offer diverse niches over approximately 5000 m elevation and approximately 1150 nautical miles. Each site hosted a distinct prokaryotic community dominated by Bacteria. Cloned sequences fell into 158 groups from 18 Bacteria phyla, while seven were unassigned and two belonged in the Euryarchaeota. Only seven operational taxonomic units (each OTU comprised sequences that shared > or =97% sequence identity) occurred in more than one site. Pure bacterial cultures from all sites fell into 155 groups (each group comprised pure cultures that shared > or =97% 16S SSU rDNA sequence identity) from 10 Bacteria phyla; 15 Proteobacteria and Firmicutes were cultivated from more than one site. One hundred OTUs (60%) and 52 (33.3%) cultures shared <97% 16S SSU rDNA sequence identity with published sequences. Community structure reflected habitat chemistry; most delta-Proteobacteria occurred in anoxic and sulfidic waters of one lake, while beta-Proteobacteria were cultivated exclusively from fresh or brackish waters. Novel sequences that affiliate with an Antarctic-specific clade of Deinococci, and Candidate Divisions TM7 and BRC1, extend the geographic ranges of these phyla. Globally and locally remote, as well as physically and chemically diverse, Hawaiian aquatic habitats provide unique niches for the evolution of novel communities and microorganisms.

l-DOPA reverses the hypokinetic behaviour and rigidity in rotenone-treated rats

Peripherally and locally administered rotenone (an inhibitor of mitochondrial complex I) has been proposed as a model of Parkinson's disease (PD) as it induces nigrostriatal degeneration associated with alpha-synuclein inclusions. If rotenone-induced symptoms represent a model of PD, than they should be counteracted by L-DOPA. To answer this question, rats were treated with rotenone 2.5 mg/kg over 48 days. Behavioural data showed a strong increase in catalepsy, a decrease in locomotor activity and biochemical data showed a significant depletion of dopamine levels in the striatum (Cpu) and substantia nigra in rotenone treated animals compared to vehicle. To examine the effectiveness of L-DOPA in reversing the motor deficit in rats, a dose of L-DOPA (10 mg/kg) in combination with the peripheral amino acid decarboxylase inhibitor benserazide were daily administrated intraperitonially for a period of 10 days in the rotenone-treated rats. This treatment counteracted catalepsy and increased locomotor activity and number of rearings but decreased inactive sitting. In this animal model (rotenone model), catalepsy tests and motor activities showed that the clinically used anti-parkinsonian drug L-DOPA substitutes rotenone-induced dopamine (DA) deficiency.

Triacylglycerol hydrolase: role in intracellular lipid metabolism

Recent scientific advances have revealed the identity of several enzymes involved in the synthesis, storage and catabolism of intracellular neutral lipid storage droplets. An enzyme that hydrolyzes stored triacylglycerol (TG), triacylglycerol hydrolase (TGH), was purified from porcine, human and murine liver microsomes. In rodents, TGH is highly expressed in liver as well as heart, kidney, small intestine and adipose tissues, while in humans TGH is mainly expressed in the liver, adipose and small intestine. TGH localizes to the endoplasmic reticulum and lipid droplets. The TGH genes are located within a cluster of carboxylesterase genes on human and mouse chromosomes 16 and 8, respectively. TGH hydrolyzes stored TG, and in the liver, the lipolytic products are made available for VLDL-TG synthesis. Inhibition of TGH activity also inhibits TG and apolipoprotein B secretion by primary hepatocytes. A role for TGH in basal TG lipolysis in adipocytes has been proposed. TGH expression and activity is both developmentally and hormonally regulated. A model for the function of TGH is presented and discussed with respect to tissue specific functions.

The neurobehavioral changes induced by bilateral rotenone lesion in medial forebrain bundle of rats are reversed by L-DOPA

Rotenone (an inhibitor of mitochondrial complex I) has been proposed as a model of Parkinson's disease (PD) as it induces nigrostriatal degeneration associated with alpha-synuclein inclusions. So far, only peripherally administered rotenone has been used as a model of PD. There has not been any investigation on the neurobehavioral changes induced by bilateral lesions of dopaminergic neurons by rotenone in rats. In the present study, rotenone (3 microg) was administered bilaterally stereotaxically into the medial forebrain bundle (MFB) to produce parkinsonian symptoms. Behavioural and biochemical data showed a strong increase in catalepsy, a decrease in locomotor activity and a significant depletion of dopamine levels in the striatum as compared to sham-lesioned animals. If the locomotor deficits are caused by the depletion of dopaminergic neurons, then L-DOPA should counteract motor deficits because L-DOPA therapy reverses mostly all motor deficits in human Parkinsonian patients. To examine the effectiveness of L-DOPA in reversing the motor deficit in rats, two different doses of L-DOPA (5 and 10 mg/kg) in combination with the peripheral amino acid decarboxylase inhibitor benserazide were daily administrated intraperitonially for a period of 31 days lesioned animals. L-DOPA plus benserazide counteracted catalepsy dose-dependently and increased locomotor activity. The results indicate that rotenone infused into the MFB destroys dopaminergic neurons, induces pakinsonian symptoms that are reversed by the clinically effective anti-parkinsonian drug L-DOPA. Therefore, sterotaxically infused rotenone may be useful for screening drugs for the treatment of PD.

Nonablative laser and light therapy: an approach to patient and device selection

Nonablative laser and light therapy is a relatively novel modality for the improvement of the visual appearance of photodamaged, scarred, and injured skin. A number of different wavelengths and devices have been purported to be efficacious for the delivery of nonablative therapy. Among the features that can be addressed are red spots and telangiectasia, pigmentation and lentigines, and their daily routines while benefiting from the cumulative effects of skin rejuvenation.

Seasonal variation in bacterial pathogens isolated from stool samples in Karachi, Pakistan

OBJECTIVE

To determine the seasonal variation of the commonly isolated bacterial pathogens in stool samples.

MATERIAL AND METHODS

A retrospective descriptive study was undertaken of all the stool samples submitted from within Karachi to the Aga Khan University Hospital Laboratory over a period of five years (January 1997- December 2001) in order to determine the commonly isolated bacterial pathogens and to predict their seasonal variation.

RESULTS

A total of 16379 stool samples were included in this review. Bacterial isolates were found in 6670 stool samples (culture detection rate=40.7%). The mean age at the time of culture of each sub-group was < or = 1 year group (6.58 +/- 3.1 months), 1-5 years (2.13 +/- 0.94 years), 5-14 years (8.3 +/- 2.6 yrs) and adults (43.2 +/- 18.5 years). Male: Female ratio was 1.2:1. Vibrio cholera 01 Ogawa (32.8%), Campylobacter jejuni (17.3%), Enteropathogenic Escherichia coli (9.9%), Salmonella paratyphi b (6.6%) and Shigella flexneri (6.2%) were the most common organisms isolated. These organisms show a distinct seasonal variation with summer predilection.

CONCLUSION

In contrast to the previous studies from South Asia, which have identified E. coil, followed by Vibrio cholerae as the most common enteric isolates, we found Vibrio cholera 01 Ogawa followed by Campylobacter jejuni as the most common enteric pathogens isolated in an urban setting. It is important to consider seasonal variation when empirically treating diarrheal diseases in our region.

Randomized trial of parathyroidectomy in mild, asymptomatic primary hyperparathyroidism as measured by the SF-36 health survey

Background

Management of patients with asymptomatic primary hyperparathyroidism (HPT) remains controversial despite a National Institutes of Health consensus statement on this issue. As part of the above statement, a randomized clinical trial was recommended since none exist to address this issue.

Methods

Informed consent was obtained from 53 asymptomatic patients with confirmed primary HPT who agreed to participate in this randomized clinical trial of parathyroidectomy versus observation. Upon entry to the study and 24 months later the patients completed the SF-36 health survey which is an instrument that measures nine different levels of function. Scores were tabulated and the difference over 24 months between operated and non-operated patients was compared with Student's t test.

Results

Fifty-three patients (42 women and 11 men) with asymptomatic, mild primary HPT (serum calcium 10·1–11·5 mg dl−1) who agreed to participate were randomized into either a surgical group or an observation group. Mean serum calcium for these patients was 10·3 mg dl−1. The only demographic difference between the groups was age; the operated group was older (66·7 versus 62·6 years; P &lt; 0·03). Scores on three of the nine domains (health perception, emotional problems and social functioning) on the SF-36 were significantly different (P &lt; 0·05), all favouring the operated group.

Conclusion

Improved function, as measured by the SF-36 health assessment tool, is seen after parathyroidectomy compared with non-operated patients. This work supports surgical management of mild primary HPT at the time of diagnosis since many patients have reversible non-classical symptoms of the disease.

Limited breast reduction by liposuction

Traditionally, dermatologic surgeons have referred women seeking breast reduction to plastic surgeons for excisional mammoplasty. However, with recent advances in small cannula tumescent liposuction surgery, referral for such surgery may be unnecessary in some cases. Breast liposuction can reduce the size of female breasts that have essentially normal architecture with a minimum of visible scarring and an aesthetically pleasing result. We describe a method for liposuction reduction of female breasts that is safe, efficacious, and associated with high levels of patient satisfaction. Liposuction for breast reduction in women is an appropriate addition to the array of liposuction procedures available to the dermatologic surgeon.

Rotenone destroys dopaminergic neurons and induces parkinsonian symptoms in rats

Rotenone (an inhibitor of mitochondrial NADH dehydrogenase, a naturally occurring toxin and a commonly used pesticide) appears to reproduce the neurochemical, neuropathological and behavioural feature of Parkinson's disease (PD) in the rat. In this study, rotenone was administrated on a daily basis systemically by intraperitoneal injection of two different doses: 1.5 mg/kg (low dose) and 2.5 mg/kg (moderate dose), over a period of 2 months. This treatment caused depletion of dopamine in the posterior striatum (CPu) and prefrontal cortex and also reduced tyrosine hydroxylase-immunoreactivity in CPu. Behavioural experiments showed dose-dependent catalepsy in the two treatment groups of rats. Data from this study indicate that in rats rotenone is capable of causing degeneration of dopaminergic neurons and induction of parkinsonian symptoms. It is concluded that the causal mechanisms of neuronal degeneration implicate a complex I deficiency in the aetiology of rotenone-induced and perhaps in some cases of sporadic PD.

Functional reconstruction of the non-human primate mandible using recombinant human bone morphogenetic protein-2

The purpose of this study was to evaluate the long-term functional properties of regenerated bone induced by recombinant human bone morphogenetic protein-2 (rhBMP-2) in segmental bone defects of primate mandibles. The 30-mm defects were created in the mandibles of six young monkeys and the mandibles were fixed with titanium plates. Then 9 mg of rhBMP-2 permeating a poly-D, L-lactic-co-glycolic acid-coated gelatin sponge (PGS) was implanted into the bone defect. Dental implants were placed into the regenerated mandible 20 weeks after surgery, then suprastructures were placed and masticatory force loading was begun 8 weeks after the insertion of the dental implants. Bone formation and the quality of new bone were evaluated radiologically and histologically at 15 and 30 weeks after surgery, and 4 and 24 weeks after masticatory force loading. The resected mandibles were completely regenerated with the rhBMP-2-induced bone. Excellent remodelling and consolidation of new bone were observed after loading. This study demonstrated that the new bone induced by rhBMP-2 in large segmental defects was maintained and functional for at least 1 year. Bone regeneration induced by rhBMP-2 holds promise as a future therapy and may be an effective alternative to autogenous bone grafts for implant dentistry and reconstructive surgery.

Anorexic behaviour and attitudes among female medical and nursing students at a private university hospital

OBJECTIVE

To study the anorexic behaviour and attitude among female medical and nursing students in a tertiary care hospital.

SUBJECTS AND METHODS

A cross-sectional survey to determine the proportion of anorexic behaviour among female medical and nursing students at The Aga Khan University Hospital Karachi was conducted. A multistaged sampling technique was utilized in which our study population was first divided according to field of enrollment (medical or nursing school) and then stratified by class. Within each stratum, we used convenience sampling due to time and availability constraints. We utilized a modified Eating Attitudes Test (EAT-26) to collect data. The Eating Attitude Test is probably the most widely used standardized measure of symptoms characteristic of eating disorders, including anorexia nervosa.

RESULTS

A total of 180 female students were interviewed. Ninety-four (52.2%) were medical students and 86 (47.8%) were nursing students. Among the 94 medical students, 26 (27.7%) were from first year, 14 (14.9%) from second year, 15 (16.0%) from third year, 20 (21.3%) from fourth year and 19 (20.2%) from the final year of medical college. Among the 86 nursing students 34 (39.5%) were from first year, 23 (26.7%) from second year, 27 (31.4%) from third year and 2 (2.4%) from fourth year. The proportion of anorexic behaviour among medical students was 8.0%, 7.1% and 20.0% in first, third and fourth years respectively. No individuals with anorexic behaviour were found in second and fifth years. The total proportion of anorexic behaviour among female health care students was 21.7%.

CONCLUSION

Results showed a 21.7% prevalence of anorexic behaviour, a figure much higher than that reported in similar studies conducted in Asia. We also found that the proportion was much higher among female nursing students as compared to female medical students. A previous visit to a psychiatrist for reasons other than eating disorders was found to be associated with anorexic behaviour.

Differential effects of doxorubicin on atrial natriuretic peptide expression in vivo and in vitro

Doxorubicin (Dox) is a potent anti-cancer agent with cardiotoxic side-effects but the mechanism of its cardiotoxicity and its effect on expression of the vasoactive atrial natriuretic peptide (ANP), an important marker for cardiac hypertrophy, are little understood. The present study examined Dox-induced changes in vivo in hearts of 6 mongrel dogs and 5 Sprague-Dawley rats and in vitro in cardiac cultures of neonatal rats. Quantitative RT-PCR analysis using gamma 32-p labeled primers for beta-actin, phospholamban (PLB) and ANP showed a selective 5-fold increase of ANP mRNA in Dox-treated dog hearts in comparison to controls. Similarly, northern analysis of GAPD, beta-actin, cardiac alpha-actin and ANP gave a selective 4.5-fold increase in ANP transcripts in Dox-treated rat hearts. On the other hand, there was a selective decrease (approximately 39%) of ANP transcripts in Dox-treated cardiac cultures relative to controls. Immunohistochemistry localized the ANP changes both in tissue sections and in cultures to the cardiomyocytes. The data clearly showed that Dox selectively increases ANP expression in dog and rat hearts in absence of cardiocyte hypertrophy but selectively decreases it in cardiac cultures. This differential effect of Dox on cardiocytes in vivo and in vitro should be a useful parameter for studies of transcriptional control of ANP expression.