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Biomedical subjects

M Arslan

Publications and source records attributed to M Arslan.

At least 55 records · Page 3Linked to original sources
PubMed2000

Antimicrobial and biological effects of ipemphos and amphos on bacterial and yeast strains.

In this study, the antimicrobial effects of monophosphazenes such as SM ipemphos and amphos were examined on bacterial and yeast strains. In addition, the biological effects of these compounds were tested on the lipid level of Saccharomyces cerevisiae and Candida albicans cells. The SM has an antimicrobial effect on the bacterial and yeast strains within the range of 100 and 1500 microg. When the concentration was increased, the inhibition zone expanded on the growth media ( p < 0.01; p < 0.001). The ipemphos did not affect the bacterial and yeast cells in the 100 and 600 microg range. In addition, the amphos did not show an antimicrobial effect on the bacterial cells between 100 and 300 microg or on yeast cells at any of the administered concentrations. In vitro media, the biological effects of these molecules were compared with vitamin E, melatonin and fish oil on the yeast cells. We have found that monophosphazenes have growth effects on the cells in vitro media. The lipid level of S. cerevisiae cells was decreased by 300 microg doses of vitamin E, fish oil, and ipemphos (respectively; p < 0.05, p < 0.01, and p < 0. 001). In addition, the lipid levels of the same yeast cells were depressed by 1000-microg doses in all supplemented groups. However, it was observed that the highest decrease in lipid level of S. cerevisiae cells occurred in the amphos group ( p < 0.001). The lipid levels of the C. albicans cells were significantly reduced ( p < 0.01) by 300 microg of amphos and melatonin. In contrast, the vitamin E and fish oil significantly raised ( p < 0.01; p < 0.001) the lipid level of the same yeast cell, as compared with the control. In addition, the lipid level of these cells was increased by administration of 1000 microg vitamin E, and melatonin ( p < 0.01). In conclusion, while high concentrations of ipemphos and amphos have an antimicrobial effect on bacterial and yeast cells, amphos did not affect the yeast cells. While ipemphos and amphos increased cell growth in media, they reduced the lipid level of C. albicans and S. cerevisiae. In addition, the antioxidants such as vitamin E, melatonin, and fish oils affected the lipid level of yeast cells.

Anti-Bacterial Agents↗
PubMed2000

Hepatitis A antibodies in liver transplant recipients: evidence for loss of immunity posttransplantation.

Liver transplant recipients frequently have chronic liver diseases and should be considered for vaccination against hepatitis A virus (HAV). However, persistence of protective antibodies after orthotopic liver transplantation (OLT) has not been shown in this population, which may have implications for future vaccine recommendations. We evaluated the prevalence and epidemiological significance of immunoglobulin G (IgG) antibody to HAV (anti-HAV) in a nonvaccinated population before OLT (immunity from previous exposure) and determined the persistence of IgG anti-HAV at 1 and 2 years after OLT. One hundred consecutive patients were identified who underwent OLT and had at least 2 years of follow-up post-OLT. They were not vaccinated against HAV infection at any time. Clinical data were summarized from medical records, and stored sera were tested for IgG anti-HAV before OLT and at 1 and 2 years after OLT by a commercially available enzyme immunoassay. Of 100 patients, 24 had IgG anti-HAV before OLT. No epidemiological differences were noted between those with or without detectable IgG anti-HAV before OLT. Among patients with detectable IgG anti-HAV before OLT, 4 of 22 patients (18%) and 7 of 24 patients (29%) became negative for IgG anti-HAV at 1 and 2 years post-OLT, respectively. None of the patients with undetectable IgG anti-HAV before OLT became positive at any time. Most of our patients with end-stage liver disease had no serological evidence for immunity against HAV. A significant proportion of patients with detectable protective antibodies before OLT lost their antibodies at 2 years after OLT.

Adolescent↗
PubMed2000

Antimicrobial and Biological Effects of Bomphos and Phomphos on Bacterial and Yeast Cells.

In this study, the antimicrobial effects of monophosphazenes such as SM, BOMPHOS, and PHOMPHOS were examined on bacterial and yeast strains. In addition, the biological effects of these compounds were tested on the Saccharomyces cerevisiae and Candida albicans cells. The SM has an antimicrobial effect on the bacterial and yeast strains within the range of 100 and 1500 µg. When the concentration was increased, the inhibition zone expanded on the growth media (P < 0.01; P < 0.001). Like SM, BOMPHOS molecule has antimicrobial activity on the bacterial and yeast cells. The most effective concentrations of BOMPHOS on the microorganisms were observed by 1500 µg (P < 0.001). The PHOMPHOS did not effect on the bacterial and yeast cells between 100 and 1000 range, but it has an antimicrobial effect in 1500 µg. In vitro media, the biological effects of these molecules were compared with vitamin E, melatonin, and fish oil on the yeast cells. In S. cerevisiae growth media, the cell densities were increased SM, BOMPHOS, and PHOMPHOS after 20, 30, and 45 h. The highest increase in the cell density were observed in media of BOMPHOS. In C. albicans growth media, the cell density was increased by melatonin after 20, 30, and 45 h, but were decreased by other supplemental groups. Lipid level of S. cerevisiae was reduced by administered 300 and 1000 µg vitamin E and fish oil (P < 0.01). In addition, the lipid level of the same yeast cell were diminished by the 1000 µg melatonin and 300 µg PHOMPHOS (P < 0.05, P < 0.01). The lipid level of C. albicans were increased by vitamin E and BOMPHOS and fish oil, but was decreased with PHOMPHOS (P < 0.01). In conclusion, while high concentration of PHOMPHOS has antimicrobial effects on the bacterial and yeast cells, the SM and BOMPHOS have antimicrobial effects in all the concentrations. PHOMPHOS decreased the lipid level of C. albicans, but BOMPHOS increased in the the same yeast cell. In addition, the antioxidants such as vitamin E, melatonin, and fish oils have affected on the lipid synthesis of yeast cells. Copyright 2000 Academic Press.

Journal Article↗
PubMed2000

Testosterone modulates growth hormone secretion at the hypothalamic but not at the hypophyseal level in the adult male rhesus monkey.

We investigated a possible modulation of growth hormone (GH) secretion by testosterone by measuring the growth hormone releasing hormone (GHRH)-stimulated and N-methyl-d,l-aspartic acid (NMA)-induced GH secretion in adult rhesus monkeys. Intact, orchidectomized and testosterone-substituted (testosterone enanthate 125 mg/week, i.m. for 5 weeks) orchidectomized monkeys (n=5) were used in the study. GHRH (25 microg/kg body weight) or NMA (15 mg/kg body weight) was infused through a Teflon cannula implanted in the saphenous vein. Sequential blood samples were collected 30-60 min before and 60 min after the injection of the neurohormone or the drug at 10-20-min intervals. All bleedings were carried out under ketamine hydrochloride anaesthesia (initial dose 5 mg/kg body weight i.m., followed by 2.5 mg/kg at 30-min intervals). The plasma concentrations of GH, testosterone and oestradiol (E(2)) were determined by using specific assay systems. Administration of GHRH elicited a significant increase in GH secretion in all three groups of animals. There was no significant difference in the responsiveness of pituitary somatotrophs to exogenous GHRH challenges between intact and orchidectomized monkeys and testosterone replacement in orchidectomized animals did not significantly alter the GHRH-induced GH response. The responsiveness of hypothalamic GHRH neurones apparently did undergo a qualitative change after orchidectomy, as GH response to NMA was less in orchidectomized animals than in intact monkeys. The responsiveness of GHRH neurones to exogenous NMA was restored and even potentiated when orchidectomized monkeys were treated with testosterone. Taken together, these findings suggest that testosterone does not affect the sensitivity of the pituitary somatotrophs to GHRH but stimulates the secretion of GH by modulation of the NMDA drive to GHRH neurones.

Analysis of Variance↗
PubMed1999

Clinical significance of TT virus infection in patients with chronic hepatitis C.

OBJECTIVE: The TT virus (TTV) is a novel DNA virus that has recently been identified. The clinical significance of TTV infection in patients with chronic hepatitis C has not been determined. The aim of this study was to determine the prevalence and possible role of TTV in a well characterized population with chronic hepatitis C infection. METHODS: Ninety patients with chronic HCV and known time of HCV acquisition were selected from approximately 250 patients followed at our institution. Characteristics including age, sex, histology, and length of disease were recorded. Direct sequencing of the NS5 region was used for HCV genotyping. TTV DNA detection was based on PCR. RESULTS: TTV infection was present in 24 of 90 (27%) HCV patients. Patients were divided into four groups based on stage of disease; chronic hepatitis (CH, 29 patients), compensated cirrhosis (CC, 17 patients), decompensated cirrhosis (DC, 28 patients), and hepatocellular carcinoma (HCC, 16 patients). TTV was present in 2/29 (7%), 2/17 (12%), 11/28 (39%), and 9/16 (56%) in those with CAH, CC, DC, and HCC respectively. TTV was significantly more prevalent among those with advanced disease (DC and HCC) compared to those with stable disease (CH and CC; p = 0.001). Mean age, sex, and the time from exposure to HCV to development of complications were similar in TTV-positive and -negative patients. TTV infection was more common in patients infected with HCV genotype 1b. Univariate analysis showed that length of HCV infection, HCV genotype 1b, and TTV infection were important in predicting the stage of liver disease in HCV patients. However, after adjusting for length of HCV infection, TTV but not HCV genotype was important in predicting the stage of liver disease. CONCLUSIONS: We conclude that 1) TTV infection is common in patients with chronic HCV; 2) TTV infection is more prevalent among patients with advanced HCV-associated liver disease (DC and HCC) than in those with stable disease (CH and CC); and 3) TTV infection is more common in patients with HCV genotype 1b but is independent from genotype in predicting the stage of HCV-associated liver disease.

Base Sequence↗
PubMed1999

The cycle duration of the seminiferous epithelium remains unaltered during GnRH antagonist-induced testicular involution in rats and monkeys.

Although the gonadotropic control of the spermatogenic process is well established, the endocrine regulation of the timing and kinetics of germ cell development has received little attention. We found previously that the administration of a GnRH antagonist (ANT) over a period of 25 days could retard spermatid development and slightly prolong cycle length in intact adult cynomolgus monkeys (Macaca fascicularis). The aim of the present study was to investigate the effects of extended exposure to ANT on the duration of the cycle of the seminiferous epithelium in the monkey. Additionally, the duration of spermatogenesis was studied in the ANT-exposed rat model. In experiment 1, monkeys were given either saline or ANT (n=6/group) and on day 30 all animals received a single injection of 5-bromodeoxyuridine (BrdU) to label S-phase germ cells. Testicular biopsies were taken on days 39, 43, 47 and 51 (end of treatment) for BrdU localization and flow cytometric analysis. ANT treatment suppressed hormone levels, reduced testis size by >70% and severely impaired germ cell production. Despite these alterations, cycle duration remained unchanged at all time-points compared with controls (10.12+/-0.15 days vs 10.16+/- 0.44 days). In experiment 2, adult male Sprague-Dawley rats (n=15/group) received either vehicle (VEH) or ANT for 14 days and received BrdU injection on day 2. Cycle duration was found to be shorter in the ANT-treated group (12.45+/-0.09 days) than in the control group (12.75+/-0.08, P<0.05). As spermatogenic cycle length in this control group was longer than that of our historical controls (range: 12.37-12.53 days), experiment 2 was repeated (n=10/group). In experiment 3, cycle duration was 12.51+/-0.02 for VEH and 12.46+/-0.05 for the ANT-treated group (P>0.05) in both species. We concluded that the duration of the cycle of the seminiferous epithelium in monkeys and rats is independent of gonadotropins but is rather regulated by the spermatogenic tissue itself.

Animals↗
PubMed1998

Seroprevalence of enzootic bovine leukosis in Trakya district (Marmara region) in Turkey.

In this study, 481 cattle belonging to 77 farms from nine localities in Trakya district in the Marmara region of Turkey were blood sampled and serologically tested for enzootic bovine leukosis (EBL). Antibodies to bovine leukosis virus (BLV) were detected in 51 cattle sera (11%) belonging to nine farms in five localities. Cattle tested were mostly female Holstein or Brown Swiss of ages ranging between 18 months and 10 years. Analysis of the relationships between age, breed or sex and seropositivity to EBL in seropositive herds indicated no significant associations (p > 0.05). The relationship between seropositivity and haematological changes was also studied, and seropositive cattle had higher lymphocyte percentage and lower neutrophil percentage than seronegative cattle (p < 0.001).

Animals↗
PubMed1998

Separation of motile spermatozoa from frozen-thawed buffalo semen: swim-up vs filtration procedures.

Three experiments were conducted to maximize the recovery rate of motile spermatozoa from frozen-thawed buffalo semen. In Experiment 1, the swim-up of motile spermatozoa was performed in the presence or absence of HEPES in TALP medium and CO2 in the environment. The recovery rate of motile spermatozoa in TALP medium (control), TALP + HEPES + CO2, TALP + HEPES and TALP + CO2 was 15, 18, 12 and 10%, respectively (P > 0.05), with sperm motility at 87, 89, 90 and 90%, respectively (P > 0.05). In Experiment 2, the pH of TALP medium was adjusted to 7.0, 7.5, 8.0, 8.5 and 9.0, and swim-up procedure was performed in the presence of HEPES and CO2. The recovery rate of motile spermatozoa at different pH was 14, 20, 24, 27 and 16%, respectively (P < 0.05). Motility of separated spermatozoa was 88, 91, 90, 89 and 90%, respectively (P > 0.05). In Experiment 3, the efficiency of ion-exchange filtration and Swim-up procedure in separating motile spermatozoa from frozen-thawed buffalo semen was compared. The recovery rate of motile spermatozoa was 95% in filtration procedure and 33% in swim-up procedure (P < 0.005). In all experiments, normal acrosomes did not vary due to treatments (P > 0.05). In conclusion, HEPES and CO2 had no significant effect on swim-up of buffalo spermatozoa. The pH 8.5 of TALP improved the recovery rate of motile spermatozoa in swim-up procedure. The ion-exchange filtration was found superior to swim-up procedure in harvesting maximum number of motile spermatozoa from frozen-thawed buffalo semen (95 vs 33%; P < 0.001).

Animals↗
PubMed1998

Hormonal regulation and germ cell-specific expression of heat shock protein 60 (hsp60) in the testis of macaque monkeys (Macaca mulatta and M. fascicularis).

Decrease of heat shock protein 60 (hsp60), a mitochondrial chaperonin, in germ cells of men has been shown to be associated with low spermatogenic efficiency. In the present study, we have investigated the hormonal regulation of hsp60 in a pre-clinical primate animal model. Hsp60 production in the testes of the intact cynomolgus monkey (Macaca fascicularis) and animals that had been treated with the GnRH antagonist Cetrorelix for 25 days was studied by immunohistochemistry. In addition, testes of untreated adult rhesus monkeys (Macaca mulatta) and immature animals either exposed to human chorionic gonadotrophin (hCG), human follicle stimulating hormone (FSH) or hCG and FSH in combination, as well as vehicle-treated controls were analysed. In adult monkeys, specific hsp60 staining was observed in Leydig cells, spermatogonia and early primary spermatocytes. The labelling in Sertoli cells was not stage dependent. The hsp60 staining pattern was unaffected by gonadotrophin releasing hormone (GnRH) antagonist treatment. Western blot analysis confirmed the presence of a single band of 60 kDa in testicular homogenates of the cynomolgus monkey. In the testis of immature rhesus monkeys, hsp60 immunoreactivity was visible in gonocytes, spermatogonia and in Sertoli cells, whereas interstitial cells were negative. In the experimental study, hCG alone or in combination with FSH caused a substantial and marked upregulation of the chaperonin in Leydig cells. Human FSH alone did not affect hsp60 expression. We conclude that hCG is an important regulator of Leydig cell hsp60 expression during development, whereas FSH in immature animals and GnRH in adult monkeys is of less importance.

Animals↗
PubMed1998

The inhibiting effect of cola on gastric mucosal cell cycle proliferation in humans.

BACKGROUND: Acidic beverages may be involved in regulating the cell proliferation of the gastric mucosa. We therefore analyzed the interaction of Coca-Cola consumption and gastric mucosal proliferation by means of flow cytometry. METHODS: Sixteen healthy students agreed to participate in this study. All volunteers underwent an oesophagogastroduodenoscopy after a 12-h overnight fast. Endoscopic changes in the gastric mucosa were determined quantitatively. One day later, after a 12-h overnight fast, all volunteers received standard Coca-Cola (200 ml, pH 2.6, 4 degrees C). One hour later all volunteers again underwent oesophagogastroduodenoscopy, to measure gastric mucosal damage. During both the first and the second endoscopy at least four biopsy specimens were taken from the antrum for flow cytometric analysis. RESULTS: The endoscopic analysis showed that there was no difference before and after Coca-Cola consumption. However, the flow cytometric analysis showed that Coca-Cola inhibited the proliferation index and the S phase. Before Coca-Cola consumption G0/G1: 60 (57-62), G2/M: 0.6 (0.2-1), S: 40 (37-42), and PI: 0.40 (0.38-0.43) and after Coca-Cola consumption G0/G1: 70 (60-73), G2/M: 1.9 (1.2-2.5), S: 28 (26-32), and PI: 0.30 (0.27-0.34) the cell population G0/G1 and G2/M phases were significantly increased (P < 0.0001, 0.0003), and the cell population S and PI phases were significantly low compared with the pre-consumption data (P < 0.0002, 0.0001). CONCLUSION: The cell cycle analysis reflects that Coca-Cola inhibits a crucial event in the cell cycle occurring at the G1/S border.

Adult↗
PubMed1998

The Effect of Glibornuride on Plasma Atrial Natriuretic Factor Levels in Patients with Newly Diagnosed NIDDM.

The aim of this clinical trial was to study the participation of plasma atrial natriuretic factor (ANF) in the risk of developing diabetic nephropathy by increasing the intraglomerular pressure. The effect of glibornuride on the plasma ANF levels and natriuresis was estimated in 10 newly diagnosed NIDDM patients and 10 control subjects. At base line, plasma ANF levels (15.05+/-2.32 pg/ml and 11.13+/-0.85 pg/ml) and the urinary sodium and potassium excretion rates were similar in patients and control subjects, respectively. Similarly, intravenous saline infusion (2 mmol/kg/60 min) resulted in remarkable elevation of plasma ANF levels in patients and in controls (28.89+/-4.72 pg/ml and 20.18+/-2.48 pg/ml, respectively) and in increased urinary sodium and potassium excretion rates in both groups. In contrast, after a single dose of 50 mg glibornuride p.o. the saline infusion did not increase ANF levels (15.13+/-1.00 pg/ml), while natriuresis but not kaliuresis persisted. All tests were performed during euglycemic clamp. It was suggested that glibornuride, with its natriuretic effect through the ATP sensitive potassium channels on the apical membrane of the thick ascending limb of loop of Henle and cortical collecting duct cells might inhibit the elevation of plasma ANF levels in response to extracellular fluid volume expansion. Similarly, with its natriuretic effect, it protects the diabetic patients against possible sodium retention. This result is considered noteworthy, since the inhibition of plasma ANF elevation in early diabetes by glibornuride may prevent glomerular hypertension and subsequent development of nephropathy.

Journal Article↗
PubMed1998

A case of Costello syndrome with endocrine features.

The case of a 21-year-old woman with findings consistent with Costello syndrome (CS) is reported. Most previously reported cases of CS were in young children. In addition to the classic features, the patient had endocrine disturbances including secondary amenorrhea, goiter, and adrenal insufficiency. This last abnormality may be the cause of the hypoglycemic episodes seen in CS. Osteoporosis and anemia were additional features. This case provides new information on the endocrine features and prognosis of CS.

Abnormalities, Multiple↗
PubMed1997

Estimation of the duration of the cycle of the seminiferous epithelium in the non-human primate Macaca mulatta using the 5-bromodeoxyuridine technique.

A comparatively low yield of germ cells has been reported for the spermatogenic process in primates. Kinetic studies of spermatogenesis and the spermatogenic cycle are needed to investigate this phenomenon but require the application of radioactively labeled compounds or irradiation. We have therefore investigated the suitability of a non-radioactive approach, viz., administration of 5-bromodeoxyuridine, for the determination of the kinetics of the spermatogenic cycle in a non-human primate, the rhesus monkey (Macaca mulatta). Four adult in-season animals received a bolus of 33 mg/kg 5-bromodeoxyuridine, one testis from each monkey was removed 3 h later and the other testis after 10 days and 11 h. Tissue was fixed in Bouin's solution and embedded in Paraplast. 5-Bromodeoxyuridine was localized by immunogold-silver staining with a monoclonal antibody. PAS-hematoxylin counterstaining was used for spermatogenic stage identification. At 3 h, the leptotene and zygotene spermatocytes in stages VII-IX were the most advanced 5-bromodeoxyuridine-positive cells. At 10 days 11 h, the label had advanced and pachytene spermatocytes in stages VI-IX contained 5-bromodeoxyuridine. The duration of the spermatogenic cycle was 10.42+/-0.07 days (range: 10.25-10.62 days). Peritubular cells and interstitial cells were rarely 5-bromodeoxyuridine-positive, and Sertoli cells were consistently negative for 5-bromodeoxyuridine. Importantly, our kinetic data closely resemble those obtained by means of the application of irradiation for this macaque species. We conclude that administration of 5-bromodeoxyuridine represents a non-radioactive reliable approach for studying kinetic aspects of the spermatogenic process in primates.

Animals↗
PubMed1997

Missed arterial injuries in military patients.

BACKGROUND: Military vascular injuries frequently result from fragment wounds while civilian vascular injuries usually are caused by gunshot wounds. The natural history of untreated major injuries by small low velocity fragments is not well known. This study evaluated the nature of these wounds. METHODS: From 1990 to 1995, 40 patients with a delayed diagnosis of an arterial injury in the extremity, abdomen, or neck were treated. The median delay between injury and diagnosis was 60 days. All patients had been seen at other military hospitals immediately after trauma. RESULTS: During initial hospitalization, immediate exploration had been performed in 23 patients and arteriogram in 3 patients. According to analysis of the records of patients, none of them had hard signs of vascular injury at the time of initial evaluation after trauma. Complications of missed arterial injuries included the following: false aneurysm, 21 (52.5%); arteriovenous fistula, 14 (35%); and occlusion, 5 (12.5%). The superficial femoral artery (n = 11) was the most commonly injured vessel. The remaining arteries included the following: carotid, 2; vertebral, 1; subclavian, 5; axillary, 2; brachial, 3; radial or ulnar, 2; internal iliac, 2; common femoral, 1; profunda femoris, 2; popliteal, 1; tibioperoneal, 8. Thirty-eight patients had penetrating wounds (21 fragments, 9 gunshot, 3 shotgun, 5 stab wounds), and only 2 patients had blunt trauma. All patients underwent surgery. There were no deaths and no loss of extremity, but 10 patients had fair results and only 4 patients required later reoperation. CONCLUSION: Traumatic arterial injuries that particularly are caused by low-velocity small fragment wounds can result in serious delayed complications months or even years after the injury. Patients with penetrating injuries must be closely monitored, and arteriography is recommended to evaluate the conditions of patients with potential vascular injury even when overt clinical signs or symptoms of vascular injury are absent.

Abdominal Injuries↗
PubMed1997

Fasting-induced suppression of hypothalamic-pituitary-gonadal axis in the adult rhesus monkey: evidence for involvement of excitatory amino acid neurotransmitters.

The present study was designed to examine whether acute food-restriction in non-human primates, suppresses hypothalamic-pituitary-testicular (HPT) axis via alterations in the excitatory amino acid (EAA) neurotransmitter-utilizing drive to the GnRH neuron. This was achieved indirectly by comparing the plasma testosterone (T) responses to administration of an excitatory amino acid analogue, N-methyl-D,L-aspartic acid (NMA), in acutely fasted and normal fed monkeys. A set of 4 chair-restrained adult male rhesus monkeys, was assigned to the following treatments: a) normal feeding, b) one-day fasting (omission of morning and afternoon meals), c) normal feeding+NMA (15 mg/kg BW) and d) one-day fasting+NMA (15 mg/kg BW). Starting 1 h after the provision or omission of the afternoon meal, frequent blood sampling was initiated at 15-min intervals for a period of 3-h. NMA was administered as an iv bolus 1 h after start of the sampling. Secretion of T was affected (P<0.005) by the treatments. A peak in T was evident during the first h of the sampling in fed but not fasted monkeys. Mean 3-h T concentrations were suppressed (P<0.001) by the fasting. Administration of NMA in fasting conditions resulted into an acute stimulation of T secretion in 2 of the 4 monkeys. However, mean 60-min post-NMA T concentrations were greater (P<0.05) than those prevailing during the same period in fasted animals not given NMA. In contrast, all 4 fed-monkeys showed significant T elevations in plasma immediately following the NMA challenge and mean T levels during the 60-min post-NMA period were higher (P<0.05) than those in fed animals not injected with NMA, at a comparable time. Testosterone area under the curve for the 2-h post-NMA period was greater (P<0.05) in fed- than in fasted-monkeys. These results indicate that although NMA can stimulate GnRH release both in fed and short-term fasting conditions, the response appears to be suppressed in the later situation suggesting that fasting-induced suppression of the HPT axis in the adult male rhesus monkey may involve a reduction in the sensitivity of GnRH neurons to the EAA neurotransmission.

Animals↗
PubMed1997

Aneurysm of the membranous septum in adult patients with perimembranous ventricular septal defect.

OBJECTIVE: The aneurysm of the membranous septum (AMS) has often been considered as benign in the minds of many previous investigators. We have analyzed the complications with AMS in adult patients. METHODS: Fifty-one cases (20%) of AMS in 254 adult patients with perimembranous ventricular septal defect (VSD) are described. The diagnosis of AMS was based on angiographic criteria. Thirty-nine (76.5%) of the 51 patients with AMS were aged between 20 and 29 years. All patients but one with AMS had a pulmonary-to-systemic flow (Qp/Qs) of less than 2.3 (range 1-2.1, mean 1.4). In a patient who had a ruptured aneurysm, the Qp/Qs was 2.7. There were six main complications affected by AMS and/or VSD; aortic valve prolapse in 24 patients (47%), aortic regurgitation in 15 (29.4%), tricuspid insufficiency in nine (17.6%), right ventricular outflow tract obstruction in two (4%), and rupture of the aneurysm in one patient (2%). Seven patients (13.7%) had prior bacterial endocarditis. All patients underwent surgery. Aneurysm and VSD were closed by direct suture in nine and with a patch in 42 patients. Aortic valve repair was performed in 13 patients in whom regurgitation was mild to moderate, and replacement was required in two patients with severe aortic regurgitation. RESULTS: There were no early or late deaths. Residual communication and recurrence of the aneurysm was noted three and seven years postoperatively in two patients where VSD had been closed by direct suture. CONCLUSIONS: According to present data, aneurysm formation functionally reduces the VSD size, but it has the potential consequence of promoting tricuspid insufficiency, aortic valve prolapse, right ventricular outflow tract obstruction, rupture and bacterial endocarditis. Therefore, we recommend that AMS should be resected completely and the defect produced closed with a patch in order to prevent further enlargement and consequent complications even if there are no cardiac symptoms.

Adolescent↗