Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 52
Filter
1.
Med J Malaysia ; 66(2): 146-7, 2011 Jun.
Article in English | MEDLINE | ID: mdl-22106698

ABSTRACT

Gallbladder tuberculosis (GT) is an extremely rare condition. This is thought to be due to the protective property of bile against the infection. Clinical and radiological diagnosis of GT is difficult. We describe a case of GT who initially presented to us with jaundice, a right hypochondrial mass and computed tomographic findings suggestive of gallbladder empyema. Diagnosis was made from histopathological examination of the resected gallbladder which revealed epitheloid granulomas with caseating necrosis and presence of Langhan's giant cells. From a literature search and to the best of our knowledge, this is the first GT to be reported in South East Asia.


Subject(s)
Candidiasis/diagnosis , Cholecystitis/diagnosis , Cholecystitis/etiology , Tuberculosis/diagnosis , Candidiasis/complications , Candidiasis/therapy , Cholecystitis/therapy , Humans , Male , Middle Aged , Tuberculosis/complications , Tuberculosis/therapy
2.
Singapore Med J ; 50(8): 772-6, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19710974

ABSTRACT

INTRODUCTION: Sabah, formerly known as North Borneo, is part of East Malaysia. 52.2 percent of patients with breast cancer in Sabah presented at advanced stages and up to 20.4 percent of patients defaulted proper treatment, opting for traditional therapy. We performed a two-year prospective study looking at the treatment trends of breast cancer in Sabah. METHODS: Our subjects were all newly-diagnosed breast cancer cases seen at the hospital in 2005 and 2006. Type of surgery, chemotherapy, radiotherapy, hormonal therapy and surgical complication for each patient were studied. RESULTS: Out of 186 newly-diagnosed cases, 152 (81.7 percent) had surgery, 126 (67.7 percent) had chemotherapy, 118 (63.4 percent) had radiotherapy and 92 (49.5 percent) had hormonal therapy. 18.3 percent did not have surgery either due to refusal of treatment or advanced disease. They were more likely to be non-Chinese (91.1 percent, p-value is 0.02). Only 15.8 percent had breast-conserving surgery. The most frequent surgical complication was seroma formation (15.0 percent) . The commonest chemotherapy regime and hormonal therapy were anthracycline-based regime (88.1 percent) and tamoxifen (95.8 percent), respectively. CONCLUSION: The proportion of breast-conserving surgery and usage of modern adjuvant therapies are low in Sabah. This can be attributed to lack of breast cancer awareness leading to late presentation and refusal of treatment, coupled with insufficient health service funding.


Subject(s)
Breast Neoplasms/diagnosis , Breast Neoplasms/epidemiology , Breast Neoplasms/therapy , Adult , Aged , Breast Neoplasms/prevention & control , Early Detection of Cancer , Female , Humans , Malaysia , Medical Oncology/trends , Middle Aged , Neoplasm Staging , Patient Compliance , Prospective Studies , Surveys and Questionnaires , Treatment Outcome
3.
Singapore Med J ; 49(11): e300-2, 2008 Nov.
Article in English | MEDLINE | ID: mdl-19037533

ABSTRACT

True and pseudoaneurysms of the visceral arteries are uncommon. They represent 0.1-0.2 percent of all vascular aneurysms. Visceral artery aneurysms (VAAs) should be treated due to their propensity to rupture and associated high mortality. We describe a 58-year-old man with pseudoaneurysm of the inferior pancreaticoduodenal artery and who presented with post-motor vehicle accident abdominal pain and a pulsatile epigastic mass. Computed tomography (CT) showed a pseudoaneurysm of the visceral artery, and selective mesenteric angiography showed the aneurysm to be arising from the inferior pancreaticoduodenal artery. The aneurysm was successfully treated with endovascular coil embolisation. CT angiogram at one month post-procedure revealed persistent occlusion of the aneurysm. To the best of our knowledge, this is the first reported pseudoaneurysm of inferior pancreaticoduodenal artery secondary to blunt abdominal trauma from a motor vehicle accident and also the first reported VAA from Malaysia.


Subject(s)
Aneurysm, False/etiology , Aneurysm, False/therapy , Duodenum/pathology , Pancreas/blood supply , Vascular Surgical Procedures/methods , Accidents, Traffic , Angiography/methods , Celiac Artery/diagnostic imaging , Hepatic Artery/diagnostic imaging , Humans , Male , Mesenteric Artery, Superior/diagnostic imaging , Middle Aged , Tomography, X-Ray Computed/methods , Treatment Outcome
4.
Med J Malaysia ; 63(2): 148-9, 2008 Jun.
Article in English | MEDLINE | ID: mdl-18942304

ABSTRACT

Synchronous cancers are defined as malignant tumours that occur simultaneously, each of which must be distinct with no possibility of one being the metastasis of the other. A 65 year old gentleman presented to us with two month history of epigastric pain associated with anaemia, loss of appetite and weight. He has no history of malignancy in his family. Colonoscopy revealed tumours at transverse colon and caecum. Intra-operatively, tumours were sited at caecum, transverse colon and jejunum. Tumours were diagnosed as synchronous adenocarcinoma histopathologically with loss of expression of MLH1 and MSH2. From literature search, this is the first reported triple synchronous tumours of the caecum, transverse colon and jejunum. We believe that this gentleman developed triple synchronous tumour through the sporadic MSI pathway.


Subject(s)
Adenocarcinoma/pathology , Cecal Neoplasms/pathology , Colonic Neoplasms/pathology , Jejunal Neoplasms/pathology , Neoplasms, Multiple Primary/pathology , Aged , Humans , Male
5.
Br J Anaesth ; 100(5): 663-6, 2008 May.
Article in English | MEDLINE | ID: mdl-18369239

ABSTRACT

BACKGROUND: The role of routine chest radiography (CXR) after percutaneous dilatational tracheostomy (PDT) has been questioned. METHODS: We performed a prospective observational study, on a mixed medical/surgical critical care unit in a university teaching hospital. We studied all patients undergoing PDT as part of their critical care management from November 1, 2003 until July 31, 2007. All PDTs were performed under bronchoscopic guidance. After PDT, we reviewed the immediate post-procedural films to assess the utility of routine postoperative CXR. For the purposes of CXR review, we considered a procedure to be either uncomplicated or technically difficult. Clinically relevant CXR findings were new barotrauma (pneumothorax, pneumomediastinum) or a significant change in consolidation from the pre-procedure film. RESULTS: A total of 384 patients underwent PDT during the study period. Of these, 345 had immediate post-procedural CXRs available for review. There were 252 PDTs (73%) documented as uncomplicated. There were 93 (27%) technically difficult procedures, with 107 adverse events recorded. In 82 (24%) procedures, these difficulties were described as minor procedural complications [multiple attempts at needle insertion (> or = 3), minor bleeding or tracheal ring fracture]. Significant complications (mal-placement in the anterior mediastinum and major bleeding) were documented in 12 (3.5%) patients. New abnormalities were noted on 8 (2.3%) immediate post-procedural CXRs. In only one patient was there a new CXR change in an uncomplicated PDT. CONCLUSIONS: Immediate CXR after uncomplicated PDT performed under bronchoscopic guidance rarely reveals unexpected radiological abnormalities. The role of CXR after PDT appears to be restricted to those patients undergoing technically difficult and complicated procedures. A change in practice to this effect will lead to reductions in both medical costs and exposure of staff and patients to ionizing radiation.


Subject(s)
Postoperative Care/methods , Radiography, Thoracic , Tracheostomy/adverse effects , Adult , Aged , Barotrauma/diagnostic imaging , Barotrauma/etiology , Bronchoscopy , Female , Humans , Male , Middle Aged , Postoperative Complications/diagnostic imaging , Prospective Studies , Tracheostomy/methods , Unnecessary Procedures
6.
Indian J Physiol Pharmacol ; 51(1): 81-5, 2007.
Article in English | MEDLINE | ID: mdl-17877297

ABSTRACT

Brain mechanisms for the refractory period that characteristically follows ejaculation in animals and human are poorly understood. The possibility of active inhibition of brain areas being responsible for the post-ejaculatory inhibitory state has not been ruled out. Using Blood Oxygen Level Dependent (BOLD) functional magnetic resonance imaging (fMRI) we have mapped brain areas in healthy young volunteers immediately after ejaculation. Functional imaging of the brain for 30 minutes beginning after three minutes of ejaculation induced by masturbation showed spatio-temporal activation in amygdala, temporal lobes and septal areas. The septal areas were observed to be active for a shorter duration than the amygdala and the temporal lobe. Thus the temporal sequence of involvement of the above neural structures may contribute to temporary inhibition of sexual arousal/penile erection during the post-ejaculatory refractory period in humans.


Subject(s)
Brain/physiology , Ejaculation/physiology , Magnetic Resonance Imaging/methods , Adult , Amygdala/diagnostic imaging , Amygdala/physiology , Brain/diagnostic imaging , Echo-Planar Imaging/methods , Frontal Lobe/diagnostic imaging , Frontal Lobe/physiology , Gyrus Cinguli/diagnostic imaging , Gyrus Cinguli/physiology , Humans , Male , Masturbation , Preoptic Area/diagnostic imaging , Preoptic Area/physiology , Radiography , Reaction Time , Refractory Period, Electrophysiological/physiology , Septum of Brain/diagnostic imaging , Septum of Brain/physiology , Temporal Lobe/diagnostic imaging , Temporal Lobe/physiology , Time Factors
7.
Neuroscience ; 139(3): 1141-51, 2006.
Article in English | MEDLINE | ID: mdl-16533567

ABSTRACT

Several studies have suggested that noradrenergic afferents to the medial preoptic area might be involved in hypnogenesis and in lowering the body temperature, and that the alpha1 adrenergic receptors might be mediating these responses. This study was undertaken to find out the changes in sleep-wakefulness and body temperature in rats, when these adrenergic receptors of the medial preoptic area are blocked by alpha1 selective antagonist, prazosin. Adult male Wistar rats were chronically implanted with electrooculogram, electroencephalogram and electromyogram electrodes for sleep-wakefulness assessment, and a bilateral guide cannula for microinjection of prazosin at the medial preoptic area. A radio-transmitter was implanted in the abdomen for telemetric measurement of body temperature in four groups of rats. Sleep-wakefulness was also assessed telemetrically in four other groups of rats. Sleep-wakefulness recordings from these rats were done in a specialized chamber, where they could move about freely and select the ambient temperature which they prefer. Prazosin induced a dose dependent increase in wake period and in body temperature, when microinjected into the medial preoptic area. Results suggest that preoptic alpha1 adrenergic receptors mediate hypnogenic and hypothermic responses. It is proposed that the noradrenergic afferents to the medial preoptic area, by tonic activation of alpha1 adrenergic receptors, contribute towards increase in sleep especially during the daytime.


Subject(s)
Body Temperature/physiology , Preoptic Area/metabolism , Receptors, Adrenergic, alpha/metabolism , Sleep/physiology , Wakefulness/physiology , Adrenergic alpha-Antagonists/administration & dosage , Animals , Body Temperature/drug effects , Dose-Response Relationship, Drug , Electrodes, Implanted , Electroencephalography , Electromyography , Electrooculography , Injections, Intraventricular , Male , Microinjections , Prazosin/administration & dosage , Preoptic Area/drug effects , Rats , Receptors, Adrenergic, alpha/drug effects , Sleep/drug effects , Wakefulness/drug effects
8.
Neuroscience ; 139(3): 853-64, 2006.
Article in English | MEDLINE | ID: mdl-16497443

ABSTRACT

The effects of the destruction of the medial preoptic area and the lateral preoptic area with N-methyl-d-aspartic acid on sleep-wakefulness, brain temperature and thermoregulation were studied in two groups of male Wistar rats. Electroencephalogram, electrooculogram and electromyogram, along with brain temperature, were recorded for 3 days, prior to the destruction of the medial preoptic area and the lateral preoptic area, and on the 7th and 21st days after the destruction of these areas. The thermoregulatory capacity of the rats was assessed by recording their brain temperature when they were exposed to severe cold (5+/-1 degrees C) and heat (37+/-1 degrees C) before and after the lesion. Though sleep was decreased after the destruction of both the medial preoptic area and the lateral preoptic area, paradoxical sleep was reduced only by the destruction of the medial preoptic area. Decrease in sleep after the medial preoptic area lesion was brought about by a decrease in the duration of the slow wave sleep episodes and the frequency of paradoxical sleep episodes. Decrease in sleep after the lateral preoptic area lesion was brought about by a decrease in the frequency of slow wave sleep episodes. There was a significant increase in brain temperature after the medial preoptic area lesion but not after the lateral preoptic area lesion. The rats with lesion in the medial preoptic area showed deficits in thermoregulation on exposure to cold, while those with the lateral preoptic area lesion showed deficits in heat defense ability. The present findings suggest that the medial preoptic area and the lateral preoptic area regulate sleep by different modalities and that there is an anatomical segregation of heat and cold defense functions within the basal forebrain.


Subject(s)
Body Temperature Regulation/physiology , Brain Injuries/physiopathology , Preoptic Area/physiology , Sleep/physiology , Animals , Brain Injuries/chemically induced , Electroencephalography , Electromyography , Electrooculography , Excitatory Amino Acid Agonists/toxicity , Male , N-Methylaspartate/toxicity , Preoptic Area/injuries , Rats , Rats, Wistar
9.
Indian J Physiol Pharmacol ; 49(1): 103-7, 2005 Jan.
Article in English | MEDLINE | ID: mdl-15881867

ABSTRACT

To investigate the role of specific adrenoreceptors subtypes on sexual behavior, atenolol, butoxamine, a mixture of atenolol and butoxamine, and saline (vehicle) were injected into the lateral septum in four different groups of sexually active male rats. Application of a mixture of atenolol and butoxamine produced inhibition of copulatory activity. On the other hand, application of either atenolol or butoxamine alone did not inhibit copulatory activity. But it produced stimulation of some of the components of male sexual behavior. Inability of either atenolol or butoxamine to inhibit the male sexual behavior, and inhibition of the same by the mixture of atenolol and butoxamine, indicate that both beta-adrenoreceptors at the lateral septum are involved in the elaboration of male sexual behavior. Stimulation of some components of sexual behavior on application of atenolol or butoxamine could be attributed to an unbalanced activity of beta-adrenoreceptors.


Subject(s)
Atenolol/administration & dosage , Butoxamine/administration & dosage , Septal Nuclei/drug effects , Sexual Behavior, Animal/drug effects , Animals , Drug Combinations , Female , Injections, Intraventricular , Male , Rats , Rats, Wistar , Receptors, Adrenergic, beta/physiology , Septal Nuclei/physiology , Sexual Behavior, Animal/physiology
10.
Indian J Physiol Pharmacol ; 49(3): 325-30, 2005.
Article in English | MEDLINE | ID: mdl-16440851

ABSTRACT

The medial preoptic area neurons related to male sexual behaviour in rats were identified by their responses to dorsal penile nerve stimulation. These neurons were further tested with norepinephrine applied iontophoretically. From the 21 medial preoptic area neurons recorded in urethane anaesthetized rats, 17 neurons responded to dorsal penile nerve stimulation. Excitatory and inhibitory responses were found in almost equal number of neurons. 14 neurons responded to norepinephrine application, out of which six neurons were excited and eight were inhibited. The direction of changes produced by dorsal penile nerve stimulation and norepinephrine application were similar in 10 neurons. The results suggest that the sensory inputs from the genitalia are possibly gated by norepinephrine at the level of the medial preoptic area. Afferent information from the genitalia carried by dorsal penile nerve and the availability of norepinephrine at the level of the medial preoptic area probably help in maintaining adequate level of sexual arousal.


Subject(s)
Afferent Pathways/physiology , Norepinephrine/pharmacology , Penis/innervation , Preoptic Area/drug effects , Action Potentials , Animals , Electric Stimulation , Iontophoresis , Male , Neural Inhibition/drug effects , Neurons/drug effects , Neurons/physiology , Norepinephrine/administration & dosage , Rats , Rats, Wistar
11.
Neuroscience ; 116(4): 921-3, 2003.
Article in English | MEDLINE | ID: mdl-12617933

ABSTRACT

The medial preoptic area plays an important role in the regulation of male sexual behavior in rats, and this area receives orexinergic inputs. The role of orexinergic inputs in the medial preoptic area in sexual behavior has not been studied, though they have been shown to play a role in some other physiological functions. In this study, the changes in male sexual behavior in rats were studied after local injection of orexin A (Hypocretin-1) at the medial preoptic area. The results of the study showed that orexin A application at the medial preoptic area increased sexual arousal as well as the copulatory performance. Sexual arousal is one of the physiological stimuli, which influences wakefulness. It is possible that the earlier reports showing increased wakefulness, on application of orexin A at the medial preoptic area/basal forebrain, has a contribution from sexual arousal.


Subject(s)
Carrier Proteins/pharmacology , Intracellular Signaling Peptides and Proteins , Neuropeptides/pharmacology , Preoptic Area/drug effects , Sexual Behavior, Animal/drug effects , Animals , Male , Orexins , Preoptic Area/physiology , Rats , Rats, Wistar , Sexual Behavior, Animal/physiology
12.
Indian J Exp Biol ; 39(6): 594-9, 2001 Jun.
Article in English | MEDLINE | ID: mdl-12562025

ABSTRACT

Primary cultures were established with nodal segments from juvenile shoots of two- year-old Paulownia fortuneii trees from a clonal plantation in Andhra Pradesh. A medium containing half-strength MS salts + RAP (1 mg/L) + sucrose (2%) produced optimum bud break in nodal explants. The same basal medium with reduced hormone level (0.5 mg/L) supported maximum multiplication of secondary cultures of P. fortuneii (1:6 in 6 weeks). Specific treatments were tested to enhance this rate of multiplication. In one approach, five to six week old in vitro grown shoots were ratooned (cutting the main shoot at the bottom leaving one node). The stumps (ratooned basal node) produced 2 to 3 axillary shoots, which grew into 4 to 5 nodes by 3 weeks; thus, providing additional shoots from the same explant. This provided 30% additional shoots in 4 cycles. Secondly, reducing the light intensity to 1200 lux resulted in higher shoot elongation, i.e, formation of 8 nodes in 5 weeks with healthier shoots than the normal intensity of 3000 lux under which only 6 nodes were produced in 6 weeks. In vitro-grown shoots could be successfully rooted ex vitro in vermiculite + cocopeat mixture (1:1 v/v) under 90% humidity, transferred to soil in polybags for hardening in the green house for 2 weeks and shifted to shade net for further hardening. After one month, the plants could be successfully transplanted to field with 95% survival. Micropropagated plants showed an excellent growth in the field attaining a height of 1.5 m and a collar diameter of 2.8 cm in 3 months.


Subject(s)
Lamiaceae/growth & development , Plant Shoots/growth & development
13.
Indian J Physiol Pharmacol ; 45(4): 445-50, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11883151

ABSTRACT

This study was conducted to find out whether the medial preoptic area (mPOA) plays a role in the selection of ambient temperature by rats. Adult male Wistar rats were kept in an environmental chamber having three interconnected compartments, maintained at three different temperatures (18 degrees, 24 degrees and 30 degrees C) in which the animals could move freely from one compartment to the other. Normal rats preferred to stay at the chamber maintained at 24 degrees C for most of the time, during day and night. The temperature preference shifted to 30 degrees C after the mPOA of these rats had been lesioned by local administration of 5 micrograms of N-methyl D-aspartic acid (NMDA) in 0.2 microliter distilled water. The results of the study suggest that the mPOA acts as a fine tuning center for homeostatic regulation of thermal balance, including selection of appropriate thermal environment. It is proposed that after the mPOA lesion, the animal cannot assess properly the energy status of the body and thereby prefers a higher ambient temperature.


Subject(s)
Preoptic Area/physiology , Animals , Body Temperature Regulation , Energy Metabolism , Male , Rats , Rats, Wistar , Temperature
14.
Sleep Res Online ; 3(3): 141-5, 2000.
Article in English | MEDLINE | ID: mdl-11382912

ABSTRACT

The changes in sleep-wakefulness were studied in rats during their exposure to different ambient temperatures of 18 degrees C, 24 degrees C and 30 degrees C, before and after the destruction of the medial preoptic area neurons by N-Methyl D-aspartic acid. In normal rats, there was an increase in paradoxical sleep and slow wave sleep and a decrease in wakefulness at higher ambient temperatures. The increase in sleep was primarily due to an increase in the duration of sleep episodes. Destruction of the medial preoptic area neurons produced a decrease in sleep at all three different ambient temperatures. But, there was a linear increase in sleep with higher temperatures in the lesioned rats that was qualitatively different from that in the normal animals, as the increase in sleep was associated with an increase in the number of short duration slow wave sleep episodes. The findings indicate that the medial preoptic area is essential for sleep maintenance and improving the quality of sleep with higher ambient temperatures. It is possible that the medial preoptic area serves as a fine-tuning mechanism to regulate sleep for energy homeostasis, including thermoregulation.


Subject(s)
Preoptic Area/physiopathology , Sleep/physiology , Wakefulness/physiology , Analysis of Variance , Animals , Electroencephalography , Electromyography , Electrooculography , Male , N-Methylaspartate/administration & dosage , Preoptic Area/drug effects , Preoptic Area/pathology , Rats , Rats, Wistar , Sleep Stages/physiology , Temperature , Time Factors
15.
Int J Androl ; 22(3): 139-47, 1999 Jun.
Article in English | MEDLINE | ID: mdl-10367233

ABSTRACT

The effects of long-term administration of testosterone enanthate on the pharmacokinetics and bioavailability of testosterone were studied in adult male rhesus monkeys (n = 9), injected with 50 mg of testosterone enanthate (TE) once every 14 days for a total of 32 months. Control animals were injected with 0.2 mL olive oil. Serum testosterone levels increased sharply within 24 h of the first injection of TE and reached a peak on day 3 followed by a sharp decline, but baseline values were not reached even by day 14. Subsequent injections of TE caused a similar pharmacokinetic profile until the 55th injection; testosterone levels on day 3 declined from the 56 to 58th injection and remained in a lower range until the last injection. Repeated injections of TE increased the bioavailability of testosterone as shown by the Area Under the Curve. The nocturnal (22.00 h) surge in testosterone levels during the pretreatment phase was abolished by TE injections. TE injections altered the metabolism of testosterone by the liver, as studied in vitro; while liver from control animals converted testosterone to androstenedione as the major metabolite, androsterone was the major metabolite in chronically TE-treated animals. Spermatogenesis and the associated increase in testicular volume observed in control animals in winter were suppressed in TE-treated animals. The results indicate that repeated TE injections elevate serum testosterone to supra-physiological levels with marked fluctuations in circulating testosterone levels after each injection. Possibly in response to these elevated levels, there was a change in the metabolism of testosterone by the liver as observed in vitro.


Subject(s)
Contraceptive Agents, Male/pharmacokinetics , Liver/metabolism , Testis/drug effects , Testosterone/analogs & derivatives , Animals , Contraceptive Agents, Male/administration & dosage , Liver/drug effects , Macaca mulatta , Male , Testis/pathology , Testosterone/administration & dosage , Testosterone/pharmacokinetics , Time Factors
16.
Indian J Physiol Pharmacol ; 43(4): 415-24, 1999 Oct.
Article in English | MEDLINE | ID: mdl-10776456

ABSTRACT

The regulation of blood glucose is generally stated to be under the control of the endocrine system. But the endocrine secretion is itself regulated by the central nervous system, especially the hypothalamus. The brain can sense the energy status of the body by using neural afferent signals and metabolic cues such as glucose. A variety of experimental evidences have been put forth to support the postulate that there are "glucoreceptors", sensitive to blood glucose and glucose utilization, in the hypothalamus. Gastrointestinal afferents, which carry information about the energy intake, reach the hypothalamic regions and interact with the glucose sensitive mechanisms. Available evidence suggests that obesity and decreased body weight, resulting from lesions of the hypothalamic 'satiety' and 'feeding' centres respectively, are not only due to altered food intake, but also to derangement in glucose homeostasis. The medial preoptic area does the fine tuning of energy balance (regulation of food intake) in response to alterations in the temperature, locomotor activity and sleep wakefulness. Thus the hypothalamus regulates energy balance through its control of energy intake on the one hand, and its expenditure and storage on the other. Neuroendocrine system and autonomic nervous system deal with storage and expenditure of energy.


Subject(s)
Blood Glucose/metabolism , Nervous System Physiological Phenomena , Animals , Autonomic Nervous System/physiology , Brain/physiology , Brain Stem/physiology , Eating/physiology , Energy Metabolism , Homeostasis , Humans , Hypothalamus/physiology , Insulin/metabolism , Signal Transduction
17.
Sleep Res Online ; 2(2): 49-55, 1999.
Article in English | MEDLINE | ID: mdl-11382882

ABSTRACT

The experiments were conducted on 24 adult male Wistar rats to find out the alterations in the levels of monoamines and dendritic spine densities in the medial preoptic area and cortex after total sleep deprivation. Noradrenaline was reduced in the medial preoptic area, though there was no significant change in the cortex. Dopamine and serotonin were decreased both in the medial preoptic area and in the cortex. Dendritic spine counts in the medial preoptic area and the motor cortex were increased after total sleep deprivation. Enhanced release of the monoamines and their subsequent breakdown during sleep deprivation could be responsible for the decreased levels of the transmitters. An increase in synaptic activity, resulting in the enhanced release of the transmitters, might be responsible for the increased spine density after total sleep deprivation. Localized changes in noradrenaline levels at the medial preoptic area suggest its involvement in sleep genesis and maintenance, though its possible contribution to other functions like thermoregulation and reproduction cannot be ruled out. As the available literature does not indicate a role for serotonin and dopamine at the medial preoptic area in sleep regulation, these changes may represent their participation in non-sleep functions.


Subject(s)
Biogenic Monoamines/metabolism , Dendrites/physiology , Preoptic Area/metabolism , Sleep Deprivation , 3,4-Dihydroxyphenylacetic Acid/metabolism , Animals , Dopamine/metabolism , Hydroxyindoleacetic Acid/metabolism , Male , Motor Cortex/cytology , Motor Cortex/metabolism , Norepinephrine/metabolism , Preoptic Area/cytology , Rats , Rats, Wistar , Serotonin/metabolism
18.
Sleep ; 21(6): 587-98, 1998 Sep 15.
Article in English | MEDLINE | ID: mdl-9779518

ABSTRACT

This study was undertaken to determine the effects of the destruction of the medial preoptic area (mPOA) neurons by N-methyl D-aspartic acid (NMDA), on sleep-wakefulness (S-W), locomotor activity, body weight, rectal temperature, and food and water intake in rats. The NMDA lesion of the mPOA produced long-lasting insomnia with marked reduction in the deeper stages of sleep, including paradoxical sleep. The reduction in the duration of sleep episodes in the lesioned rats indicated their inability to maintain sleep. The insomnia resulting from a decreased sleep pressure did not alter the sleep-initiating ability. Though the day-night distribution of sleep remained largely unaffected, there was an increase in locomotor activity during the light period. There was no increase in food intake to compensate for the high energy expenditure resulting not only from hyperactivity but also from hyperthermia in the mPOA-lesioned rats. Thus, body weights of the rats were reduced even without any change in food and water intake. However, the changes in body temperature and locomotor activity after the mPOA neuronal loss may not have exerted a major influence on S-W, as the alterations in all these parameters had different time courses.


Subject(s)
Drinking Behavior/drug effects , Feeding Behavior/drug effects , Locomotion/drug effects , N-Methylaspartate/pharmacology , Neurons/drug effects , Neurons/pathology , Optic Chiasm/drug effects , Optic Chiasm/pathology , Preoptic Area/drug effects , Sleep/drug effects , Animals , Male , Rats , Rats, Wistar , Time Factors , Wakefulness/drug effects
19.
Sleep ; 21(6): 601-6, 1998 Sep 15.
Article in English | MEDLINE | ID: mdl-9779519

ABSTRACT

Changes in sleep after fetal preoptic (POA) tissue transplantation were studied in rats which had been made insomniac by a medial preoptic area (mPOA) lesion. Two days after the N-methyl D-aspartic acid (NMDA) lesion of the mPOA, fetal POA tissues (obtained from 14- to 17-day-old fetuses) were transplanted into the lesioned mPOA. Insomnia was less marked in these animals, as compared to nontransplanted lesioned rats, even on the 4th day after transplantation. The quantum of sleep nearly attained the prelesion level by the 20th day. Body weight also showed recovery after transplantation. Rectal temperature, which was increased by the lesion of the mPOA, remained unaltered even after the transplantation. These results suggest that the recovery of sleep and rectal temperature may follow different time courses. Surviving transplanted neurons were seen at the site of lesion on postmortem examination. Humoral interaction between the host and the transplant may be responsible for the early recovery of sleep, though the establishment of neural connections between the host and transplant might have contributed to the later recovery. This is the first study to show the recovery of sleep function in insomniac animals after fetal preoptic tissue transplantation. However, the specificity of the POA fetal tissue, in comparison with other neural tissues to promote sleep recovery, remains to be established.


Subject(s)
Fetal Tissue Transplantation , Preoptic Area/surgery , Sleep, REM/physiology , Animals , Body Temperature , Male , N-Methylaspartate/pharmacology , Postoperative Period , Preoptic Area/drug effects , Rats , Wakefulness
20.
Indian J Exp Biol ; 36(3): 264-72, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9754059

ABSTRACT

DEHP [di-(2 ethyl hexyl) phthalate], a widely used plasticizer in blood storage bags, leaches out in appreciable amounts into blood (about 10 mg/100 ml) resulting in exposure of recipients of blood transfusion to this compound. Various reports indicate the toxicity of DEHP, particularly in liver and reproductive organs but all these studies used large doses (up to 2 g or more/Kg body weight) and oral route of administration which are not relevant to the intravenous administration during blood transfusion or the low amounts present in blood. We have studied changes in the activity of some important enzymes-gamma-GT, ALT, CPK, LDH, alkaline phosphatase, acid phosphatase, beta-glucuronidase and few other parameters like vitamin E, glutathione, serum albumin etc in rats administered low doses of DEHP (corresponding to transfusion of 2, 4, 6 and 10 units of blood). Histopathology of the organs has also been carried out. The results obtained indicate no serious toxic effects for DEHP at the level present in blood stored in DEHP plasticized blood bags as evidenced by the lack of any significant alteration in most of the biochemical parameters studied. Even in those cases where there was alteration (for e.g., decrease in the level of vitamin E) 24 hr after administration of DEHP, it returned to near normal level with in 72 hr to 7 days. No histopathological changes were observed in any of the organs at these levels of DEHP. It is concluded that DEHP did not cause any serious toxic effect even at doses corresponding to transfusion of several units of blood in a recipient.


Subject(s)
Diethylhexyl Phthalate/toxicity , Animals , Diethylhexyl Phthalate/administration & dosage , Male , Organ Size/drug effects , Rats , Rats, Wistar
SELECTION OF CITATIONS
SEARCH DETAIL
...