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1.
J Taibah Univ Med Sci ; 17(2): 332-339, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35592799

ABSTRACT

This case-series aims to report three cases of endogenous endophthalmitis due to invasive Klebsiella pneumoniae syndrome. Case 1: A 34-year-old lady who was admitted for pneumonia developed painful blurring of vision and redness in the right eye (RE) for one week. An examination of the RE revealed visual acuity (VA) of light perception (PL) with positive relative afferent pupillary defect (RAPD), proptosis, and restriction of extraocular movement with hypopyon. The patient was treated for RE panophthalmitis with a lung abscess and was started on systemic and topical antibiotics. The vitreous tap culture grew Klebsiella pneumoniae. Despite treatment, the patient's condition deteriorated, and evisceration was undertaken. Case 2: A 38-year-old lady presented with a acute onset of RE pain associated with blurred vision and redness for two days, and fever for one week. RE VA was hand movement with a positive RAPD and anterior chamber cells of 2+. A B-scan revealed a dome-shaped subretinal mass with exudative retinal detachment. The patient was treated for RE panophthalmitis complicated by a basal ganglia abscess. The urine and vitreous tap cultures grew Klebsiella pneumoniae. She responded to high-dose intravenous and intravitreal antibiotics. Unfortunately, her RE became phthisical. Case 3: A 70-year-old lady presented with painless blurring of vision over the RE. The blood and urine cultures grew Klebsiella pneumoniae. RE VA was PL, and she was treated for endogenous endophthalmitis. The vitreous culture grew Klebsiella pneumoniae. Unfortunately, the RE became phthisical.

2.
Med J Malaysia ; 76(4): 569-572, 2021 07.
Article in English | MEDLINE | ID: mdl-34305121

ABSTRACT

Leptospirosis is a zoonotic disease that is caused by the pathogenic spirochetes of the genus Leptospira. The infection occurs worldwide and is particularly more common in the tropics. However, it is becoming a neglected reemerging global health disease due to rapid urbanisation. This disease has a wide range of clinical manifestations from flu-like illness to pneumonia, acute kidney injury, etc. But many uncommon clinical findings are being reported as well. In this paper, we report four patients who presented initially with uveitic features who turned out serologically positive for Leptospira after extensive investigations.


Subject(s)
Leptospira , Leptospirosis , Humans , Leptospirosis/diagnosis
3.
Article in English | MEDLINE | ID: mdl-32164271

ABSTRACT

Children with autism spectrum disorder (ASD) are reported to participate less in everyday activities, and their parents face stigma on account of having a child with ASD, which they often internalize as affiliate stigma. Studies have examined the impact of affiliate stigma on parents' psychological well-being and social behaviors, but little is known about how affiliate stigma impacts their children's activity participation. This study aimed to investigate the relationship between parents' affiliate stigma and activity participation of their children with ASD. Sixty-three parents of children with ASD (aged 2-6 years) were recruited. They completed questionnaires, which captured affiliate stigma, their child's participation (frequency and involvement) in home, preschool, and community activities, and demographic characteristics. Results indicated that these parents had a moderate level of affiliate stigma, which did not correlate with the frequency of their children's participation in activities. However, the parents' affiliate stigma was found to have negative impacts on their children's involvement in overall community participation and participation in one particular activity at home. The findings highlight the importance of destigmatization of parents of children with ASD in order to promote their children's participation in community activities.


Subject(s)
Autism Spectrum Disorder , Community Participation , Parents , Social Stigma , Child , Child, Preschool , Community Participation/psychology , Community Participation/statistics & numerical data , Female , Humans , Male , Parents/psychology , Surveys and Questionnaires
5.
Singapore Med J ; 55(6): 298-301, 2014 Jun.
Article in English | MEDLINE | ID: mdl-25017403

ABSTRACT

In the management of complex medical cases such as a multifetal pregnancy, knowledge of the ethical and legal implications is important, alongside having competent medical skills. This article reviews these principles and applies them to scenarios of multifetal pregnancy and fetal reduction. Such a discussion is not solely theoretical, but is also relevant to clinical practice. The importance of topics such as bioethical principles and informed consent are also herein addressed.


Subject(s)
Ethics, Medical , Legislation, Medical , Pregnancy Reduction, Multifetal/ethics , Pregnancy Reduction, Multifetal/legislation & jurisprudence , Pregnancy, Multiple , Female , Humans , Informed Consent , Pregnancy , Singapore
6.
J Hum Nutr Diet ; 27(3): 219-26, 2014 Jun.
Article in English | MEDLINE | ID: mdl-24112810

ABSTRACT

BACKGROUND: Lower urinary tract symptoms (LUTS) in men are associated with obesity, particularly central obesity as measured by waist circumference (WC), and may improve with weight loss. We aimed to compare effects of a meal-replacement based diet with isocaloric reduced-fat plan on LUTS and nutrient intake in obese Asian men. METHODS: Obese Asian [mean (range) body mass index of 32.9 (30.5-42.3) kg m(-2) ] men [mean (range) age 40.2 (30-61) years] were randomised to a reduced-fat (< 30% of energy) diet [conventional reduced-fat diet (CD) group; n = 23] or meal-replacement-based plan [meal replacement (MR) group; n = 23], to reduce daily intake by 2000 kJ for 12 weeks. RESULTS: CD and MR groups had statistically significant and similar reductions in weight (-2.6 ± 1.9 kg versus -4.2 ± 3.8 kg), overall LUTS severity measured with International Prostate Symptom Scale (IPSS) scores (-1.71 ± 1.93 points versus -2.42 ± 2.12 points) and insulin resistance [homeostasis model assessment (HOMA) calculated from plasma glucose and insulin]. The MR group had significantly greater decreases in WC (-4.8 ± 3.3 cm versus -2.5 ± 2.3 cm), fat mass (-2.47 ± 3.63 kg versus -1.59 ± 2.32 kg), fat intake, plasma C-reactive protein, and in storage LUTS score (-1.59 ± 1.33 points versus -1.00 ± 0.87 points), which was associated with a decreased fat intake (r = 0.48, P = 0.03). A decrease in overall IPSS score was associated with reductions in weight, WC and HOMA. CONCLUSIONS: Weight loss as a result of CD or MR had similar efficacy in relieving LUTS. MR produced greater reductions in fat intake, adiposity and storage LUTS.


Subject(s)
Diet, Fat-Restricted , Energy Intake , Obesity/complications , Urologic Diseases/diet therapy , Urologic Diseases/etiology , Adiposity , Adult , Blood Glucose/analysis , Diet , Energy Metabolism , Humans , Insulin/blood , Insulin Resistance , Male , Meals , Middle Aged , Prostatic Diseases/diet therapy , Waist Circumference , Weight Loss
7.
Int J Impot Res ; 26(2): 61-6, 2014.
Article in English | MEDLINE | ID: mdl-24196274

ABSTRACT

Sexual dysfunction is more prevalent in obese than in normal-weight men. Meal replacements (MRs) are useful weight-loss strategies. We randomized obese (body mass index 27.5 kg m(-2), waist circumference (WC) 90 cm) Asian men (mean age 40.5 years, range 30-61) to a conventional reduced-fat diet (CD) (n=24) or MR-based plan (n=24) to reduce daily intake by 400 kcal for 12 weeks. There were significantly greater reductions in weight (4.2 ± 0.8 kg), WC (4.6 ± 0.7 cm), calorie and fat intake in the MR group, compared with the CD group (2.5 ± 0.4 kg, 2.6 ± 0.5 cm). Erectile function (International Index of Erectile Function 5-item score) improved comparably in the MR (3.4 ± 0.7 points) and CD (2.5 ± 0.5 points) groups, as did the Sexual Desire Inventory score (5.5 ± 2.3 vs 7.7 ± 2.1 points), quality of life (36-item Short Form survey score), plasma testosterone and endothelial function (Reactive Hyperemia Index). Subjects were switched to or continued CD for another 28 weeks. Weight, WC and erectile function were maintained at 40 weeks. MR induces greater reductions in weight and abdominal obesity than conventional diet, and comparable improvements in sexual and endothelial function, testosterone and quality of life.


Subject(s)
Diet, Fat-Restricted , Erectile Dysfunction/etiology , Obesity/complications , Testosterone/blood , Weight Loss , Adult , Aged , Asian People , Blood Pressure , Caloric Restriction , Endothelium, Vascular/physiology , Erectile Dysfunction/diet therapy , Exercise , Humans , Insulin Resistance , Male , Middle Aged , Obesity/diet therapy , Quality of Life , Sexual Behavior
8.
Br J Anaesth ; 102(6): 869-74, 2009 Jun.
Article in English | MEDLINE | ID: mdl-19376787

ABSTRACT

BACKGROUND: The purpose of this study was to verify which muscle among the adductor pollicis (AP), orbicularis oculi (OO), and corrugator supercilii (CS) is a better predictor of optimal intubating conditions after administration of rocuronium. METHODS: In this prospective trial, 201 patients were randomized into six groups to receive rocuronium at a dose of 0.6 or 1.0 mg kg(-1) during propofol-remifentanil-nitrous oxide anaesthesia. The tracheal intubation was performed after maximal neuromuscular block by acceleromyography at the thumb (AP), the eyelid (OO), and the superciliary arch (CS). The onset time, intubating conditions, peak vital signs, and bispectral index were assessed. RESULTS: The onset time of rocuronium in the OO and CS muscle was significantly shorter than in the AP muscle (P<0.001), but excellent intubating conditions were significantly increased in the AP (87%) and the CS (77%) compared with the OO (32%) after a dose of 0.6 mg kg(-1) of rocuronium (P<0.05). CONCLUSIONS: After administration of rocuronium, twitch monitoring at the OO allows a faster intubation but is associated with an unacceptable incidence of inadequate intubating conditions. Excellent intubating conditions are observed most frequently with AP monitoring but with the longest delay before intubation is attempted. Monitoring of the CS allows intubation earlier than that of AP with fewer patients having excellent but no patients having inadequate intubating conditions.


Subject(s)
Androstanols/pharmacology , Intubation, Intratracheal/methods , Muscle Relaxation/drug effects , Muscle, Skeletal/drug effects , Neuromuscular Nondepolarizing Agents/pharmacology , Adult , Androstanols/administration & dosage , Anesthesia, General/methods , Dose-Response Relationship, Drug , Electroencephalography/drug effects , Eyelids , Facial Muscles/drug effects , Facial Muscles/physiology , Facial Nerve/physiology , Female , Hemodynamics/drug effects , Humans , Laryngoscopy , Male , Middle Aged , Monitoring, Intraoperative/methods , Muscle Relaxation/physiology , Muscle, Skeletal/physiology , Neuromuscular Blockade/methods , Neuromuscular Nondepolarizing Agents/administration & dosage , Prospective Studies , Rocuronium , Thumb , Young Adult
9.
Singapore Med J ; 48(12): 1117-21, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18043839

ABSTRACT

INTRODUCTION: Calcium supplementation and pharmacotherapy are recommended in the preventive management of osteoporosis. Many previous studies report of underdiagnosis and undertreatment of osteoporosis among elderly patients with hip fractures. We undertook this study to determine the dietary calcium levels in our local elderly population who were admitted with hip fractures. METHODS: 77 patients, between the ages of 60 and 98 years of age, and admitted to our department between January 2001 and September 2001 for hip fractures, were studied. The dietary calcium intakes of these patients were determined by a food frequency questionnaire and a detailed diet history. Bone mineral density (BMD) studies were performed on 55 of these patients to confirm the diagnosis of osteoporosis. RESULTS: The mean daily calcium intake was found to be 650 mg. Only six of our hip fracture patients (7.8 percent) had a daily calcium intake above the recommended levels of 1,000 mg per day. For the 55 patients who had BMD performed, only one patient had a BMD within the normal range. 34 patients (64.2 percent) had hip T-scores in the osteoporotic range and 18 patients (33.9 percent) had hip T-scores in the osteopenic range. We found that the patients with BMD in the osteoporotic and osteopenic ranges had no significant difference in the dietary calcium intake. CONCLUSION: The dietary calcium intake of our elderly patients with hip fractures is insufficient. They would benefit from dietary education and calcium supplements to prevent deterioration in bone density and subsequent osteoporotic fractures.


Subject(s)
Bone Density/drug effects , Calcium, Dietary/administration & dosage , Fractures, Spontaneous/prevention & control , Hip Fractures/prevention & control , Osteoporosis/prevention & control , Age Factors , Aged , Aged, 80 and over , Bone Density/physiology , Cohort Studies , Dietary Supplements/statistics & numerical data , Female , Fractures, Spontaneous/epidemiology , Fractures, Spontaneous/physiopathology , Geriatric Assessment , Hip Fractures/epidemiology , Hip Fractures/physiopathology , Humans , Male , Middle Aged , Nutritional Requirements , Nutritional Status , Osteoporosis/epidemiology , Osteoporosis/physiopathology , Risk Assessment , Sex Factors , Singapore
10.
Singapore Med J ; 48(7): e203-5, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17609816

ABSTRACT

We report a 35-year-old Chinese woman with clear cell sarcoma of the rectus sheath aponeurosis presenting as a tender anterior abdominal mass. She was treated with wide local excision. Local recurrence and distant metastasis occurred within two months of the onset of the complaint. Clear cell sarcoma is a rare cancer with a propensity for slow progressive invasion. They occur most commonly in the extremities, and the majority of patients are young adults. This case report demonstrates an unusual site of occurrence for clear cell sarcoma.


Subject(s)
Liver Neoplasms/secondary , Rectal Neoplasms/pathology , Sarcoma, Clear Cell/secondary , Adult , Female , Humans , Lymphatic Metastasis , Neoplasm Recurrence, Local
11.
Eur J Anaesthesiol ; 24(9): 789-95, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17462115

ABSTRACT

BACKGROUND AND OBJECTIVE: Neuromuscular blocking effects according to the severity of liver dysfunction have not been evaluated. We assessed the neuromuscular effects of mivacurium in carbon tetrachloride (CCl4)-treated rabbits with toxic hepatitis in vivo. METHODS: We compared the dose-response relationships and the neuromuscular blocking effects of mivacurium in 66 rabbits randomly treated with 0.3 mL kg(-1) of corn oil, 0.3 mL kg(-1) of CCl4 or 0.6 mL kg(-1) of CCl4 for 11 weeks, respectively. Train-of-four stimuli were applied every 10 s to the common peroneal nerve and the force of contraction of the tibialis anterior muscle was measured. RESULTS: Severe hepatitis was associated with a rightward shift of the mivacurium dose-response curves, but mild hepatitis had no effect. The calculated ED50 values for the control, mild and severe hepatitis were 17.1+/-2.6, 18.2+/-2.7 and 31.8+/-3.2 microg kg(-1), respectively. Rabbits with severe hepatitis had a significantly prolonged recovery time from neuromuscular blockade compared with other rabbits. Cholinesterase activity had a negative correlation with recovery indices of mivacurium even in severe hepatic injury. Severe hepatitis induced a prolongation of action duration of repeated doses, but maintained the constant intervals. CONCLUSIONS: The dose-response and the time course of neuromuscular blockade of mivacurium differ in mild hepatitis compared with severe hepatitis, but required no adjustments of different doses for repeated injection after the desired depth of neuromuscular block, and had a negative correlation with the activity of plasma cholinesterase in both hepatic injuries.


Subject(s)
Chemical and Drug Induced Liver Injury/physiopathology , Isoquinolines/pharmacology , Muscle Relaxation/drug effects , Neuromuscular Nondepolarizing Agents/pharmacology , Animals , Biomarkers/blood , Carbon Tetrachloride , Chemical and Drug Induced Liver Injury/blood , Cholinesterases/blood , Disease Models, Animal , Dose-Response Relationship, Drug , Liver Function Tests , Male , Mivacurium , Muscle Relaxation/physiology , Rabbits , Random Allocation , Time Factors
12.
Neuroscience ; 127(4): 805-12, 2004.
Article in English | MEDLINE | ID: mdl-15312893

ABSTRACT

Superficial layers of the entorhinal cortex (EC) relay the majority of cortical input projections to the hippocampus, whereas deep layers of the EC mediate a large portion of hippocampal output projections back to other cortical areas, suggesting a functional segregation between superficial and deep layers of the EC as input and output structures of the hippocampus, respectively. However, deep layers of the EC send associational projections to superficial layers, suggesting a potential interaction between neocortical input and hippocampus-processed output in superficial layers. This possibility was investigated by examining whether deep to superficial EC projections support long-term synaptic plasticity, and whether they interact with other pathways in superficial layers in rat medial EC slice preparations. Synaptic responses of the deep-to-superficial layer projections were verified based on field potential profiles, paired-pulse facilitation, physical separation between superficial and deep layers, and pharmacological manipulation. Long-term potentiation (LTP) was reliably induced in the deep-to-superficial layer projections by burst stimulations that emulated theta or sharp wave electroencephalogram (EEG),and it was blocked by an N-methyl-d-aspartate receptor antagonist (D-2-amino-5-phosphonopentanoic acid) and a calcium channel blocker (nifedipine). Prolonged low frequency stimulation induced long-term depression. A weak stimulation of deep layers, which induced a small degree of LTP by itself, generated a much larger degree of LTP when paired with a strong stimulation of superficial layers, indicating that the deep-to-superficial layer projections cooperate with other pathways in the superficial EC to enhance synaptic weights. Our results suggest that neocortical input and hippocampal output information are integrated in superficial layers of the EC.


Subject(s)
Entorhinal Cortex/physiology , Long-Term Synaptic Depression/physiology , Synapses/physiology , 6-Cyano-7-nitroquinoxaline-2,3-dione/pharmacology , Animals , Entorhinal Cortex/drug effects , Long-Term Synaptic Depression/drug effects , Male , Neural Pathways/drug effects , Neural Pathways/physiology , Neuronal Plasticity/drug effects , Neuronal Plasticity/physiology , Rats , Rats, Sprague-Dawley , Synapses/drug effects
13.
Br J Ophthalmol ; 86(3): 299-305, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11864888

ABSTRACT

AIMS: To study the long term toxic effects of intraocular benzalkonium chloride (BAC). METHODS: 19 patients exposed to intraocular BAC preserved viscoelastic during cataract surgery in February 1999 developed severe striate keratopathy immediately postoperatively. 16 patients, including two who underwent penetrating keratoplasty, were studied in the period April to June 2000. Ocular symptoms, visual acuity, biomicroscopy, intraocular pressure, dilated funduscopy, specular endothelial microscopy, and corneal pachymetry findings were recorded. The corneal and iris specimens of the two patients who underwent keratoplasty were studied by light, transmission, and scanning electron microscopy. RESULTS: Six males and 10 females, aged 64-98 years, were studied 14-16 months postoperatively. All patients were symptomatic. 12 patients had best corrected visual acuity of 6/12 or better and four patients of between 6/18 and 6/60. Five patients had corneal epithelial oedema and 11 had Descemet's membrane folds. The central corneal thickness, 620 (SD 71) microm, in affected eyes was significantly higher (p<0.005, two tailed paired t test) than that of the contralateral eyes, 563 (SD 48) microm. The endothelial cell density was significantly lower (p<0.0001, two tailed paired t test) in affected eyes: 830 (SD 280) cells/mm2 v 2017 (SD 446) cells/mm2. The mean average cell area was significantly higher in the BAC treated eyes: 1317 (SD 385) microm2 v 521 (SD 132) microm2. There was no significant difference in the coefficient of variation of cell size between the two eyes (p=0.3, two tailed paired t test). Two corneal specimens displayed morphological features of bullous keratopathy and other non-specific abnormalities. Extracellular melanosomes were present in a portion of the iris of one case. CONCLUSION: BAC is toxic to the corneal endothelium when used intraocularly, leading to severe striate keratopathy. This cleared in most cases but left varying degrees of residual stromal thickening in all eyes. If penetrating keratoplasty is required the results are excellent.


Subject(s)
Benzalkonium Compounds/adverse effects , Corneal Diseases/chemically induced , Detergents/adverse effects , Methylcellulose/analogs & derivatives , Phacoemulsification/adverse effects , Aged , Aged, 80 and over , Cohort Studies , Corneal Diseases/physiopathology , Female , Hemostatics/therapeutic use , Humans , Hypromellose Derivatives , Male , Methylcellulose/therapeutic use , Middle Aged , Visual Acuity
14.
J Neurosci Res ; 66(1): 117-21, 2001 Oct 01.
Article in English | MEDLINE | ID: mdl-11599008

ABSTRACT

We have recently shown that cholinergic effects on synaptic transmission and plasticity in the superficial (II/III) layers of the rat medial entorhinal cortex (EC) are similar, but not identical, to those in the hippocampus (Yun et al. [2000] Neuroscience 97:671-676). Because the superficial and deep layers of the EC preferentially convey afferent and efferent hippocampal projections, respectively, it is of interest to compare cholinergic effects between the two regions. We therefore investigated the physiological effects of cholinergic agents in the layer V of medial EC slices under experimental conditions identical to those in the previous study. Bath application of carbachol (0.5 microM) induced transient depression of field potential responses in all cases tested (30 of 30; 18.5% +/- 2.3%) and rarely induced long-lasting potentiation (only 3 of 30; 20.4% +/- 3.2% in successful cases). At 5 microM, carbachol induced transient depression only (20 of 20, 48.9% +/- 2.8%), which was blocked by atropine (10 microM). Paired-pulse facilitation was enhanced during carbachol-induced depression, suggesting presynaptic action of carbachol. Long-term potentiation (LTP) could be induced in the presence of 10 microM atropine by theta burst stimulation, but its magnitude was significantly lower (9.1% +/- 4.7%, n = 15) compared to LTP in control slices (22.4% +/- 3.9%, n = 20). These results, combined with our previous findings, demonstrate remarkably similar cholinergic modulation of synaptic transmission and plasticity across the superficial and deep layers of EC.


Subject(s)
Acetylcholine/physiology , Entorhinal Cortex/physiology , Long-Term Potentiation/physiology , Synapses/physiology , Animals , Atropine/pharmacology , Carbachol/pharmacology , Cholinergic Agonists/pharmacology , Long-Term Potentiation/drug effects , Male , Muscarinic Antagonists/pharmacology , Organ Culture Techniques , Rats , Rats, Sprague-Dawley , Receptors, Muscarinic/physiology , Synaptic Transmission/drug effects , Synaptic Transmission/physiology
15.
Biol Pharm Bull ; 24(7): 838-40, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11456127

ABSTRACT

The effects of benzylisoquinoline compounds such as ethaverine, laudanosine, and tetrahydropapaverine on monoamine oxidase (MAO, EC 1.4.3.4) activity in mouse brain were investigated. Ethaverine showed an inhibition of MAO activity in a concentration-dependent manner (57.6% inhibition at 40 microm). Papaverine also inhibited MAO activity (38.1% inhibition at 40 microM). However, laudanosine and tetrahydropapaverine did not inhibit MAO activity. The IC50 value of ethaverine for MAO was 25.5 microm. Ethaverine non-competitively inhibited MAO activity with a substrate kynuramine. The Ki value for ethaverine was 11.9 microM. In addition, ethaverine proved to preferentially inhibit type B MAO activity in a concentration-dependent manner, with an IC50 value of 32.8 microm. These results suggest that ethaverine partially contributes to the regulation of catecholamine content.


Subject(s)
Brain/enzymology , Monoamine Oxidase Inhibitors/pharmacology , Monoamine Oxidase/metabolism , Papaverine/analogs & derivatives , Papaverine/chemistry , Papaverine/pharmacology , Animals , Brain/drug effects , Brain Chemistry/drug effects , Catecholamines/metabolism , Kinetics , Kynuramine/metabolism , Male , Mice , Mice, Inbred ICR
16.
Muscle Nerve ; 24(4): 502-11, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11268022

ABSTRACT

The free radical, nitric oxide (NO.), has been implicated in the pathogenesis of muscular dystrophies because the enzyme, nitric oxide synthase (NOS), which produces NO., binds to the dystrophin-glycoprotein complex (DGC). In various studies of tissue samples from human and animal muscular dystrophies due to DGC defects, correlations between reductions of NOS activity and disease severity have been reported. To test for any direct effect of NOS expression on muscle cell susceptibility, we examined muscle cells in vitro under conditions of experimentally altered NOS activity. There were no differences in susceptibility to oxidative stress between differentiated myotube cultures from wild-type and from neuronal NOS (nNOS)-deficient mice. Likewise, pharmacological inhibition of NOS did not alter cellular susceptibility to oxidative challenges. Overexpression of NOS neither enhanced nor diminished cellular susceptibility to oxidative stress. Finally, we assessed the effect of NOS overexpression on myotube cultures from dystrophin-deficient (mdx) mice. NOS protein was localized to both membrane and cytosolic compartments in the transduced cells. Still, no difference in susceptibility to oxidative stress was found between the NOS-overexpressing cells and control cells. These data suggest that muscle cell susceptibility to oxidative challenges is independent of the level of NOS expression. Therefore, any role NO. may play in the pathogenesis of muscular dystrophies is likely to be independent of its effect on the redox state of the cell.


Subject(s)
Muscle, Skeletal/metabolism , Nitric Oxide Synthase/biosynthesis , Oxidative Stress/physiology , Animals , Cell Differentiation , Cells, Cultured , Disease Models, Animal , Dose-Response Relationship, Drug , Enzyme Inhibitors/pharmacology , Gene Expression/drug effects , Mice , Mice, Inbred C57BL , Mice, Inbred mdx , Mice, Knockout , Muscle, Skeletal/cytology , Muscle, Skeletal/drug effects , Muscular Dystrophy, Animal/genetics , Muscular Dystrophy, Animal/metabolism , Myofibrils/drug effects , Myofibrils/metabolism , Nitric Oxide Synthase/antagonists & inhibitors , Nitric Oxide Synthase/deficiency , Nitric Oxide Synthase/genetics , Nitric Oxide Synthase Type I , Oxidants/pharmacology , Reactive Oxygen Species/metabolism , Transfection
17.
J Neurosci Res ; 63(6): 509-15, 2001 Mar 15.
Article in English | MEDLINE | ID: mdl-11241586

ABSTRACT

We investigated the cognition enhancing effects of ginsenoside Rb1 and Rg1. Mice were trained in a Morris water maze following injection (i.p.) of Rb1 (1 mg/kg) or Rg1 (1 mg/kg) for 4 days. Both Rb1- and Rg1-injected mice showed enhanced spatial learning compared to control animals. The hippocampus, but not the frontal cortex, of treated mice contained higher density of a synaptic marker protein, synaptophysin, compared to control mice. Electrophysiological recordings in hippocampal slices revealed that Rb1 or Rg1 injection did not change the magnitude of paired-pulse facilitation or long-term potentiation. Our results suggest that Rb1 and Rg1 enhance spatial learning ability by increasing hippocampal synaptic density without changing plasticity of individual synapses.


Subject(s)
Central Nervous System Agents/pharmacology , Hippocampus/metabolism , Maze Learning/drug effects , Saponins/pharmacology , Synaptophysin/metabolism , Animals , Cognition/drug effects , Electrophysiology , Ginsenosides , Hippocampus/drug effects , Long-Term Potentiation/drug effects , Memory/drug effects , Mice , Mice, Inbred C57BL , Space Perception/drug effects , Synapses/drug effects , Synapses/physiology
18.
Neuroscience ; 97(4): 671-6, 2000.
Article in English | MEDLINE | ID: mdl-10842011

ABSTRACT

Effects of cholinergic agents on synaptic transmission and plasticity were examined in entorhinal cortex and hippocampus. Bath application of carbachol (0.25-0.75 microM) induced transient depression of field potential responses in all cases tested (24/24 in layer III of medial entorhinal cortex slices and 24/24 in CA1 of hippocampal slices; 11.0+/-1.9% and 7.8+/-2.5%, respectively) and long-lasting potentiation in some cases (4/24 in entorhinal cortex and 12/24 in hippocampus; 33.7+/-3.7% and 32.1+/-9.9%, respectively, in successful cases). Carbachol (0.5 microM) induced transient depression, but not long-lasting potentiation, of N-methyl-D-aspartate receptor-mediated responses in entorhinal cortex. At 5 microM, carbachol induced transient depression only (55. 9+/-4.7% in entorhinal cortex and 41.4+/-2.9% in hippocampus), which was blocked by atropine. Paired-pulse facilitation was not altered during carbachol-induced potentiation but enhanced during carbachol-induced depression. These results suggest that the underlying mechanisms of carbachol-induced depression and potentiation are decreased transmitter release and selective enhancement of non-N-methyl-D-aspartate receptor-mediated responses, respectively. Long-term potentiation could be induced in the presence of 10 microM atropine by theta burst stimulation. The magnitude was significantly lower (15.2+/-5.2%, n=9) compared with control (37.2+/-6.1%, n=8) in entorhinal cortex, however. These results demonstrate similar, but not identical, cholinergic modulation of synaptic transmission and plasticity in entorhinal cortex and hippocampus.


Subject(s)
Carbachol/pharmacology , Entorhinal Cortex/physiology , Hippocampus/physiology , Neuronal Plasticity/physiology , Synaptic Transmission/physiology , 6-Cyano-7-nitroquinoxaline-2,3-dione/pharmacology , Animals , Atropine/pharmacology , Electric Stimulation , Entorhinal Cortex/drug effects , Evoked Potentials/drug effects , Hippocampus/drug effects , In Vitro Techniques , Long-Term Potentiation/drug effects , Long-Term Potentiation/physiology , Magnesium/pharmacology , Male , Neuronal Plasticity/drug effects , Pyramidal Cells/drug effects , Pyramidal Cells/physiology , Rats , Rats, Sprague-Dawley , Receptors, N-Methyl-D-Aspartate/physiology , Synaptic Transmission/drug effects
19.
J Laparoendosc Adv Surg Tech A ; 9(3): 277-81, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10414546

ABSTRACT

We present two cases of sudden unanticipated cardiovascular complications in patients with noncatecholamine-secreting adrenocortical adenomas during laparoscopic adrenalectomy. In the first case, the patient developed paroxysmal tachycardia and hypertension followed by ventricular fibrillation shortly after clipping of the adrenal vein. In the second case, the patient suffered hypertension and bigeminy during manipulation of the adrenal gland just around the adrenal vein. Awareness of such complications during either conventional or laparoscopic adrenalectomy is important even if the operation is performed in a patient with an apparently noncatecholamine-secreting adrenocortical adenoma.


Subject(s)
Adenoma/complications , Adrenal Cortex Neoplasms/complications , Hypertension/etiology , Tachycardia, Paroxysmal/etiology , Ventricular Fibrillation/etiology , Adenoma/metabolism , Adenoma/surgery , Adrenal Cortex/blood supply , Adrenal Cortex/metabolism , Adrenal Cortex/surgery , Adrenal Cortex Neoplasms/metabolism , Adrenal Cortex Neoplasms/surgery , Adrenalectomy/adverse effects , Adult , Catecholamines/metabolism , Female , Humans , Intraoperative Complications/diagnosis , Laparoscopy , Veins
20.
Dev Dyn ; 212(4): 495-508, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9707323

ABSTRACT

Skeletal muscle has a remarkable capacity to regenerate after injury, although studies of muscle regeneration have heretofore been limited almost exclusively to limb musculature. Muscle precursor cells in skeletal muscle are responsible for the repair of damaged muscle. Heterogeneity exists in the growth and differentiation properties of muscle precursor cell (myoblast) populations throughout limb development but whether the muscle precursor cells differ among adult skeletal muscles is unknown. Such heterogeneity among myoblasts in the adult may give rise to skeletal muscles with different regenerative capacities. Here we compare the regenerative response of a masticatory muscle, the masseter, to that of limb muscles. After exogenous trauma (freeze or crush injuries), masseter muscle regenerated much less effectively than limb muscle. In limb muscle, normal architecture was restored 12 days after injury, whereas in masseter muscle, minimal regeneration occurred during the same time period. Indeed, at late time points, masseter muscles exhibited increased fibrous connective tissue in the region of damage, evidence of ineffective muscle regeneration. Similarly, in response to endogenous muscle injury due to a muscular dystrophy, widespread evidence of impaired regeneration was present in masseter muscle but not in limb muscle. To explore the cellular basis of these different regenerative capacities, we analyzed the myoblast populations of limb and masseter muscles both in vivo and in vitro. From in vivo analyses, the number of myoblasts in regenerating muscle was less in masseter compared with limb muscle. Assessment of population growth in vitro indicated that masseter myoblasts grow more slowly than limb myoblasts under identical conditions. We conclude that the impaired regeneration in masseter muscles is due to differences in the intrinsic myoblast populations compared to limb muscles.


Subject(s)
Muscle, Skeletal/physiology , Regeneration/physiology , Stem Cells/physiology , Animals , Cell Count , Cell Differentiation/physiology , Male , Masseter Muscle/cytology , Masseter Muscle/injuries , Masseter Muscle/physiology , Mice , Mice, Inbred C57BL , Mice, Inbred mdx , Muscle, Skeletal/cytology , Muscle, Skeletal/injuries , Muscle, Skeletal/metabolism , MyoD Protein/biosynthesis , Wounds and Injuries
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