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N Gharbi

Publications and source records attributed to N Gharbi.

At least 19 recordsLinked to original sources
PubMed2006

Protective effect of resveratrol on ethanol-induced lipid peroxidation in rats.

AIM: Chronic ethanol treatment induces an increase in oxidative stress. As polyphenolic compounds are potent antioxidants, we aimed to examine whether dietary supplementation of resveratrol may attenuate lipid peroxidation, the major end-point of oxidative damage resulting from chronic ethanol administration. METHOD: Three groups of male Wistar rats were used. The first group served as control and received a daily intraperitoneal injection of 0.9% saline. The second group of rats was daily injected with 35% ethanol at 3 g/kg body weight. The third group was given the same dose of ethanol and supplemented with resveratrol (5 g/kg) in the standard diet. Malondialdehyde (MDA), an indicator of oxidative stress, was measured in the liver, heart, brain, and testis. RESULTS: At the end of a 6 weeks treatment period, MDA levels were significantly increased by 51.5, 53.7, 72.7, and 40.5% in the liver, heart, brain, and testis, respectively. However, when ethanol treated rats were given resveratrol the increase in MDA levels was significantly reduced in all organs to nearly those of control rats. CONCLUSION: Resveratrol is able to inhibit the ethanol-induced lipid peroxidation and have protective effect against oxidative injury.

Animals↗
PubMed2006

Vasopressin and nitric oxide synthesis after three days of water or food deprivation.

Nitric oxide has been suggested to be involved in the regulation of fluid and nutrient homeostasis. In the present investigation, vasopressin and nitric oxide metabolite (nitrite and nitrate) levels were determined in plasma of male Wistar rats submitted to water or food deprivation for three days. Hematocrit and plasma sodium showed marked increase in dehydrated and starved rats. Potassium levels and plasma volume decreased in both treated groups. Plasma osmolality and vasopressin levels were significantly elevated in water deprived (362.8 +/- 7.1 mOsm/kg H2O, 17.3 +/- 2.7 pg/ml, respectively, p < 0.001) rats, but not in food deprived (339.9 +/- 5.0, 1.34 +/- 0.28) rats, compared to the controls (326.1 +/- 4.1, 1.47 +/- 0.32). The alterations observed in plasma vasopressin levels were related to plasma osmolality rather than plasma volume. Plasma levels of nitrite and nitrate were markedly increased in both water and food deprived rats (respectively, 2.19 +/- 0.29 mg/l and 2.22 +/- 0.17 mg/l versus 1.33 +/- 0.19 mg/l, both p < 0.01). There was a significant negative correlation between plasma nitrite and nitrate concentration and plasma volume. These results suggest that both dehydration and starvation increase plasma nitric oxide, probably by activation of nitric oxide synthases. The release of nitric oxide may participate in the regulation of the alteration in blood flow, fluid and nutrient metabolism caused by water deprivation or starvation.

Animals↗
PubMed2002

Parathyroid hormone concentrations during and after two periods of high intensity exercise with and without an intervening recovery period.

The purpose of this study was to examine the effect of a recovery period between two periods of exercise on bone metabolism and related hormones. Concentrations of serum parathyroid hormone ([PTH]), plasma ionized calcium ([Ca(2+)]) and total calcium were measured. A group of 12 healthy men aged 20-27 years participated in this study. They took part in two exercise protocols (P(1) and P(2)) on two separate weeks. The exercise in P(1) comprised two successive periods of 21 min each at 70% and 85% of maximal oxygen uptake; P(2) comprised two periods of exercise at the same intensities but separated by 40 min of recovery. Venous blood samples were collected 1 day before the sessions (control), before each protocol, during (7th and 21st min), at the end (42nd min in P(1) and 82nd min in P(2)) and after 24 h of recovery. The [PTH] was significantly elevated during the two protocols ( P<0.01), remained raised in P(1) after 24 h of recovery ( P<0.05) and was significantly lower ( P<0.01) at the end of P(2) when compared to P(1). The [Ca(2+)] decreased significantly during and at the end of the two protocols ( P<0.01) and had returned to control values after 24 h of recovery. Plasma lactate concentration increased during the two protocols ( P<0.01) and returned to control values after recovery. These results indicate firstly that [Ca(2+)] decreases during continuous exercise as [PTH] increases and remains raised after 24 h of recovery, secondly that a recovery period between two periods of exercise attenuates the variations in [Ca(2+)] and [PTH], and thirdly that recovery may have anabolic effects on bone. However, the small physiological changes observed prevent us from forming any firm conclusion about this.

Adult↗
PubMed2000

Vasopressin and A1 noradrenaline turnover during food or water deprivation in the rat.

In the present study, we have examined in Wistar rats the effects of food or water deprivation of 3 days on the hypophyso-adrenal axis, vasopressinergic system and activity of A1 noradrenergic brain stem cell group, which is involved in the control of the hypothalamic neuro-endocrine activity. Levels of adrenocorticotropic hormone (ACTH) and vasopressin (AVP) were determined by radio-immunoassay, and corticosterone level was determined by fluorimetric method. Plasma levels of ACTH and corticosterone were greatly increased in both groups of rats. In water-deprived rats, plasma AVP (13.83 +/- 1.63 vs. 3.03 +/- 0.23 pg/ml) and osmolality levels were significantly elevated with a marked decrease of AVP hypophysis content (272 +/- 65 vs. 1098 +/- 75 ng/mg protein), but not in food-deprived rats in which osmolality did not change and AVP remained stocked (2082 +/- 216 ng/mg protein) in the hypophysis without release in the plasma (1.11 +/- 0.23 pg/ml). These observations indicated that both food-deprivation and water-deprivation stimulated the pituitary adrenal axis thereby suggesting a stress state. AVP production is stimulated both by fluid and food restriction but is secreted with differential effects: during food restriction AVP secretion is limited to supporting the hypothalamic pituitary-adrenal system.

Animals↗
PubMed2000

[The effect of age and dehydration on the activity of the vasopressinergic system in rats].

The aim of our work was to study the different blood parameters as well as the activity of the vasopressinergic axis in young and mature male rats under normal conditions and following a 3-day dehydration cycle by water deprivation. Under normal conditions, our study demonstrates higher levels of vasopressin in mature rats as compared to young rats. This could be due in part to the higher blood osmolality in the mature rats. After dehydration, hypovolemia, plasmatic hyperosmolality, hypernatremia and hyperproteinemia cause a stimulation in vasopressin synthesis and release, as seen in results obtained from the hypothalamus, hypophysis and plasma in both young and mature rats. However, the response of the vasopressinergic axis to dehydration is greater in young rats, suggesting a more pronounced sensitivity to osmotic factors.

Aging↗
PubMed2000

[Plastic surgery in ambulatory practice].

We have analysed 283 patient studies operated of ambulatory during the last two years. These patients represent only 12% of the patient group. It's especially a matter of patients operated urgently. The local anaesthesia in the regional local was practised in terms of 90% of cases. The complications where exceptional. We wanted to insist on the necessary guidelines and pitfalls to forget during the practice of that surgery and we wanted to focus on its advantages.

Ambulatory Surgical Procedures↗
PubMed1999

Tissue norepinephrine turnover and cardiovascular responses during intermittent dehydration in the rat.

We investigated the central and peripheral sympathetic responses to intermittent dehydration in rats. The norepinephrine (NE) turnover, a biochemical index correlated with noradrenergic neuronal activity, was measured. The modification of blood pressure was also determined by telemetry during the different cycles of dehydration. Dehydration caused a decrease of NE turnover in A2, A5 and A6 nuclei and in peripheral organs. The vasopressinergic level of dehydrated rats decreased in hypophysis and hypothalamus, and increased in plasma. A repeated gradual increase of arterial blood pressure during the first three days of dehydration, followed by a sudden drop when the rats were rehydrated on the fourth day was observed. In conclusion, our study revealed an increase in blood pressure and in central sympathetic activity during dehydration.

Animals↗
PubMed1999

Effects of acute and chronic starvation on central and peripheral noradrenaline turnover, blood pressure and heart rate in the rat.

When faced with stress, an organism calls upon several mechanisms to maintain biological homeostasis. The cardiovascular system is the first to respond usually with an increase in arterial pressure and tachycardia. Therefore we investigated the central and peripheral sympathetic responses to acute and chronic starvation in Wistar rats. The noradrenaline (NA) turnover rate was determined in different catecholaminergic nuclei (A1, A2, A5, A6) as well as the arterial blood pressure and heart rate modifications. During acute starvation (3 days of starvation), the NA turnover was increased in the A1 and rostral A2 nuclei as well as in ventricles and kidneys and decreased in the A6 nucleus. During chronic starvation (4 consecutive cycles of 3 days of starvation plus 1 day of feeding), the NA turnover was increased in the A5 and caudal A2 nuclei as well as in ventricles and atria and decreased in the A1 nucleus and kidneys. The arterial blood pressure revealed a gradual decrease during the first 3 days of fasting but the heart rate was not modified. We conclude that starvation should be considered as an unusual state of stress because of the absence of locus coeruleus response (A6 nucleus) despite its well-defined role in stress reactions. One of the manifestations of these central and peripheral noradrenergic changes is the change in blood pressure during the starvation-feeding cycles.

Animals↗
PubMed1999

[Postpneumonectomy syndrome in adults: description and therapeutic propositions apropos of 8 cases].

BACKGROUND: Adult post-pneumonectomy syndrome can be defined as an extrinsic compression of the main bronchus or a lobe bronchus on the aorta resulting from excessive mediastinal deviation after pneumonectomy. PATIENTS: Eight cases in adults are reported. The delay to symptom onset was a mean 34 months. Three patients complained of increased dyspnea and 5 patients experienced a must more rapid course with adult respiratory distress syndrome in 1. Fibroscopy and chest CT confirmed the diagnosis of extrinsic compression of the main bronchus or a lobe bronchus. RESULTS: In the first 2 patients, endoscopic treatment with an endobronchial prosthesis was unsuccessful. The mediastinum was recentered in the following patients using an inflatable prosthesis positioned in the pneumonectomy cavity. Clinical improvement was achieved in all patients. Fibroscopy and chest CT confirmed the reduction in bronchial compression. DISCUSSION: Early diagnosis and mediastinal recentering are required for good outcome. Surveillance after pneumonectomy should include a search for mediastinal deviation and its consequences, particularly concerning the permeability of the remaining bronchi.

Adolescent↗
PubMed1999

[Effect of fasting on glycemia and proteinemia in young and adult rats].

The aim of Our work has consisted of studying the effects of a severe three-day fast on the evolution of the body weight, on glycemia and on proteinemia among the young and mature male rats. The decrease in body weight which is more marked among young rats after starvation shows that the loss of body mass due to fasting decreases with the age of the rats. The physiological perturbations of nutritive constants that have been recorded during this period of fast show that the mature rat first attacks its non-protein stocks or glucides, which leads to a decrease in its glycemia and in its lipids; whereas the young rat uses its proteins after only three days of starvation because of its small stock of lipids.

Age Factors↗
PubMed1998

Bronchioloalveolar lung carcinoma: results of surgical treatment and prognostic factors.

STUDY DESIGN: To determine the long-term results after surgical treatment of bronchioloalveolar lung carcinoma (BALC) and to identify prognostic factors. PATIENTS AND METHODS: A retrospective study of 70 patients (49 men, 21 women), mean age 61+/-10 years, was carried out. Their carcinomas were classified into three clinicopathologic types: nodular or tumoral, pneumonic, and diffuse types. All the diagnosed BALC cases were reviewed and were classified into histologic types: mucinous, nonmucinous (including fibrotic center), and mixed tumors. Univariate and multivariate analyses were carried out. RESULTS: The nodular or tumoral type was identified in 42 patients, pneumonic in 21, and diffuse in seven. Histologically, there were 36 mucinous, 25 nonmucinous, and nine mixed tumors. Resection was complete in 61 instances (87%) and incomplete in five. The 5-year survival rate was 34% in patients with curative resections. Five prognostic factors were identified by univariate analysis, but in multivariate analysis, only three factors remained significant: the absence of symptoms, the TNM stage, and completeness of resection. Thirty-six patients with curative resection (59%) developed recurrences (in the lung in 26 patients; mediastinal lymph nodes, four; distant metastases, nine). The frequency of recurrence was significantly greater in patients with pneumonic-type BALC than in nodular or tumoral types (p<0.01), and pulmonary recurrences were significantly more frequent in pneumonic than in tumoral types (p<0.02). CONCLUSIONS: This study confirmed that the overall prognosis of BALC is not significantly different from that of the other non-small cell lung cancers. We found that the lungs are the predominant site of recurrence in BALC, especially in the pneumonic types. The complete surgical resection of localized BALC offers the best chances of long-term survival.

Adenocarcinoma, Bronchiolo-Alveolar↗
PubMed1998

[Adrenal cortex activity in the malnourished newborn rat].

Newborn rats (4 day-old) were subjected to chronic malnutrition through their mothers submitted to an intermittent fasting (one day out of two) during 41 days. These offspring were compared with others undergoing a treatment of a 21 days malnutrition followed by 20 days ad libitum realimentation. Rats whose mothers were nourished ad libitum with a standard diet served as controls. The body growth was hindered by the malnutrition but restored when fasting was followed by realimentation. The weight of the encephalon, the heart and the ovary was unchanged. In contrast, testicle atrophy was observed without correction by realimentation. A corticoadrenal activation characterized by an increase in blood and adrenal corticosterone levels and by an adrenal gland hypertrophy was observed in undernourished animals. A lower response of the adrenal cortex to ether stress (added stress) was also observed. All these perturbations were suppressed when fasting was followed by refeeding.

Adrenal Cortex↗
PubMed1998

[Pulmonary resections for cancer in the octogenarian].

UNLABELLED: More and more elderly subjects are offered for pulmonary resection. The object of this study was to review the results of excision for cancer in octogenarians. PATIENTS: 51 consecutive patients (44 men, 7 women) with a mean age of 82 years (80-91) were operated on. 31 lobectomies, 2 bilobectomies, 13 pneumonectomies, 1 segmental resection and 4 exploratory thoracotomies were carried out. 17 tumours were classed as stage I, 15 as stage II and 15 as stage III. RESULTS: 38 patients (75%) had uncomplicated post-operative periods; the predicted factors for complication were the existence of weight loss and alteration of respiratory function. 2 patients (4%) died in the post-operative phase. Neither the type of operation, the staging or the existence of cardiovascular dysfunction had any influence on the post-operative phase. The level of the survival at 3 and 5 years was 39% and 16% respectively. 30% of the late deaths were related to intercurrent events. CONCLUSIONS: Pulmonary excision may be envisaged in an octogenarian who is in good physical and intellectual state with a limited tumour. This surgery in general is applied to a population which probably only marginally consists of octogenarians but the results here justify their inclusion in the indications for selection.

Aged↗
PubMed1997

[Effects of simulated weightlessness on the hypophyseal-cortical-adrenal axis in the pregnant rat].

The eventual part of stress in the hormonal responses to simulated weightlessness was studied during gestation in the rat. We have compared these responses with the effects of two other situations well-known to provoke stress: ultrasounds and denutrition. An increase of blood and adrenal corticosterone levels was found in mothers after denutrition, neither after ultrasounds nor after simulated weightlessness. In foetuses, a decrease of weight was noted after denutrition and simulated weightlessness. Foetal suprarenal corticosterone remained normal when mothers were submitted to simulated weightlessness. In this group, a decrease in foetal weight was found that could be explained by non suprarenal hormonal factors or by circulation disturbances.

Animals↗
PubMed1996

Cortico-adrenal function under simulated weightlessness during gestation in the rat--effects on fetal development.

To examine the effects of simulated weightlessness on cortico-adrenal function and on fetal development, we suspended pregnant rats for 20 days. The levels of adrenal and plasma corticosterone were examined in mothers and in fetuses. The animal control group was kept single in standard cages. Growth of the suspended animals was repressed for the first 8 days of the experiment, but thereafter it increased greatly, as did the daily food intake. By the 18th day of the experiment, the body masses and food intake of the two groups were equal. No modification in circulating corticosterone was found. It appears that there is no stress in pregnant rats submitted to simulated weightlessness.

Adaptation, Physiological↗
PubMed1994

Utility of C-reactive protein measurements for empyema diagnosis after pneumonectomy.

Serum C-reactive protein (CRP) levels were studied serially during the postoperative period in 151 consecutive patients who underwent pneumonectomy. Virtually all patients who had a simple postoperative course (115 of 120), as well as 9 patients who had a bronchial infection of the remaining lung, 3 with a pulmonary embolus, and 2 who suffered postoperative bleeding requiring reoperation, demonstrated a similar postoperative evolution in their CRP values: a rapid postoperative rise until a peak or a plateau (mean peak value, 132 +/- 25 mg/L) was reached within 3 to 6 days, followed by a progressive decline to a value of less than 75 mg/L on day 9, and less than 50 mg/L on day 12. Conversely, all 12 patients who suffered empyema postoperatively, as well as 3 patients with bacterial pneumonia, 1 patient with chylothorax, and 1 patient with inflammatory pericarditis, demonstrated either a markedly persistent elevation in their CRP values or a secondary rise in the levels which exceeded 100 mg/L. Because of the high sensitivity (100%) and specificity (91.4%) of the CRP levels in detecting postpneumonectomy empyema, we recommend the routine use of this measure. Furthermore, a low CRP value after pneumonectomy (less than 50 mg/L) may help in deciding whether to confidently discharge a patient from the hospital in the absence of empyema. The negative predictive value of this method was found to be 100%.

Aged↗