Antioxidant properties of propofol and erythropoietin after closed head injury in rats

Reactive oxygen species play a role during brain injury due to closed head trauma. Enzymatic or nonenzymatic antioxidants may protect brain tissue against oxidative damage. The present study was performed to assess the changes of endogenous indices of oxidative stress in serum from rats subjected to head trauma and whether treatment with propofol and/or erythropoietin (EPO) modifies the levels of endogenous indices of oxidative stress. For these purposes, female Wistar Albino rats were divided into five groups: non-traumatic sham group, trauma performed control, trauma with propofol (i.p.), trauma with EPO (i.p.) and trauma with propofol and EPO performed study groups. At the end of the experimental procedure, blood was taken by cardiac puncture to determine superoxide dismutase (SOD) and xanthine oxidase (XO) activities as well as malondialdehyde (MDA) and nitric oxide (NO) levels in serum. Serum MDA level of control traumatic brain injury (TBI) group was significantly higher than sham operation group (p<0.012). Serum MDA levels in propofol, EPO and propofol+EPO groups were found to be decreased in comparison with control group (p<0.039, p<0.030 and p<0.018, respectively). Serum NO level was found to be increased in TBI group, but difference was not statistically significant when compared to sham-operated group (p=0.092). Propofol, EPO and propofol+EPO administration efficiently reduced serum NO levels to reach sham-operated group (p<0.002, p<0.001 and p<0.015, respectively). These results suggested that acute administration of both propofol and EPO altered the indices of oxidative stress similarly against brain injury due to trauma.     

Seroprevalence of antibodies to legionella pneumophila in hemodialysis patients

Patients with chronic renal failure are at increased risk for infections because of impaired cellular immunity. This study was designed to determine the prevalence of antibodies to Legionella pneumophila serogroups 1 to 6 and to evaluate the possible risk factors for Legionnaires' disease in hemodialysis patients. Serum samples to be screened for antibodies against L pneumophila and risk factor data were collected from 252 hemodialysis patients. The overall prevalence of L pneumophila antibodies in hemodialysis patients was found to be 5.16% There was no statistically significant difference between L pneumophila seropositivity and potential risk factors. Further studies are needed to determine possible risk factors for Legionnaires' disease in hemodialysis patients.     

The solution to organ shortage in Turkey: trained transplant coordinators

The organ shortage is a social, psychological, ethical, moral, and probably legal and political problem of the 21st century. It must be solved as soon as possible to save lives; transplant coordinators are important cornerstones in this effort. The first transplant coordinator training course was organized in May, 2002, including 27 participants from different hospitals, but unfortunately only 13 were able to work as transplant coordinators in their hospitals after the course. After the course, the number of cadaveric donors in Turkey increased 12%, compared to 2001. Currently, only 14 hospitals have transplant coordinators and 12 of them are transplant centers. There is no transplant coordinator at 10 transplant centers. Only two nontransplant centers have a transplant coordinator. Eightyeight percent of donors are procured from hospitals with a transplant coordinator. According to data from the Transplantation Society meeting held in Rome, August 2000, there should be 1675 donors in Turkey, but we had only 100 for 2002 and 49 in 1999. Transplant coordinators are essential to organize donation, seeking to achieve the maximum for potential generating capacity (60 brain-dead pmp). So we need approximately 200 (3/pmp) trained transplant coordinators in Turkey but we presently have only 15% of this number.     

Plasma homocysteine levels in renal transplant patients on tacrolimus therapy

Increased plasma total homocysteine levels afford an independent risk factor to assess cardiovascular morbidity in patients with normal and impaired renal function, including stable transplant recipients. The purpose of this study was to evaluate plasma homocysteine levels and factors known to influence homocysteine metabolism (folate and Vitamin B(12)) in renal transplanted patients treated with tacrolimus. Plasma homocysteine, serum folate and serum vitamin B(12) concentrations were measured in 18 cadaveric renal transplant patients with stable function both before and 3 months after the renal transplantation. While the mean plasma homocysteine level in the renal transplant group was significantly higher than in the control group, no significant change was observed following renal transplantation under tacrolimus therapy (16.84 +/- 6.43 micromol/L vs 16.02 +/- 6.54 micromol/L). The levels of folate before and after transplantation were considerably lower than the control group; a significant effect of tacrolimus has not been observed (7.32 +/- 4.68 ng/mL and 7.55 +/- 5.20 ng/mL). Serum vitamin B(12) levels in the transplant group were significantly lower than the control group; a significant decline was seen 3 months after the renal transplantation (448.94 +/- 230.03 pg/mL vs 334.38 +/- 240.61 pg/mL). Consequently, although plasma homocysteine levels of renal transplant recipients are higher, a lowering effect of tacrolimus therapy was not observed on plasma homocysteine levels. The lower levels of folate and Vitamin B(12) in the transplant group compared to a control group supports therapy with folate and Vitamin B(12) to decrease homocysteine concentrations.     

Cigarette smoking in renal transplant recipients

Cigarette smoking may adversely influence patient and graft survival. In Europe and the United States the prevalence of cigarette smoking in dialysis patients is 35% to 40% and 25%, respectively. In Turkey, the estimated prevalence of cigarette smoking rate in the normal population is 26%. This study evaluated the rate of smoking in 63 cadaveric, and 158 living-related renal transplant recipients including (150 men, and 76 women of 38 +/- 12 years; range, 8 to 70) who were operated between 1986 and 2001. Demographic data were collected with a questionnaire delivered to patients during their routine outpatient visits. During this time period, 8 patients had died, 4 from hemophagocytic syndrome, 2 from cardiovascular disease, 1 from Kaposi sarcoma and 1 from a cerebrovascular accident. Twenty-three patients have lost their grafts. While at the time of transplantation 97 (42%) were smoking cigarettes, only 29 (12%) continued smoke after transplantation. Male gender significantly correlated with cigarette smoking (P =.000). Twelve smokers were single but 85 out of 97 were married, a statistically significant difference (P =.010). In contrast there was no significant relationship between pretransplant smoking and educational status (P =.354); graft loss and smoking (P =.129); or mortality and smoking (P =.224). There was a significant relationship between pretransplant and posttransplant smoking (P =.000). There was no relationship between pre- and post-transplant smoking and development of diabetes mellitus or hypertension. Interestingly the posttransplant serum albumin level was lower among smokers than nonsmokers (4.44 +/- 0.02 g/dL vs 4.30 +/- 0.02 g/dL; P =.019). There was a close relationship between transplantation duration and smoking.     

Colonic interposition vs. gastric pull-up after total esophagectomy

Gastric pull-up is the most frequent reconstruction after esophagectomy. In this report we aimed to compare gastric pull-up with colonic interposition in terms of graft function and patient satisfaction. Of 62 patients undergoing esophagectomy, reconstruction was performed by colonic interposition in 11 and gastric pull-up in 51 (without pyloric drainage in 44 and with pyloric drainage in 7). All esophagectomies were performed transhiatally. Patient follow-up ranged from 6 to 132 months (median 14 months). Follow-up examinations were performed 1, 9, 15, and 24 months postoperatively. The following factors were evaluated: time to the start of oral liquid and solid nutrients without vomiting, frequency of regurgitation, presence of pillow staining (night regurgitation), postprandial fullness, and degree of satisfaction during and after eating compared between groups undergoing colonic interposition and gastric pull-up with or without pyloric drainage. Among patients undergoing gastric pull-up, regurgitation was observed in 22% to 27% during follow-up. None of the patients with colonic interposition had reflux or regurgitation. Twenty-five percent of patients with gastric pull-up without drainage and 66% of patients with gastric pull-up plus drainage had reflux esophagitis at 15 months. No esophagitis was observed in patients with colonic interposition during the same period. Overall satisfaction was superior in patients undergoing colonic interposition followed by gastric pull-up with no drainage. Colonic interposition after esophageal resection is a viable option. Our study suggests that function of the replacement is better in this group of patients.     

Melatonin reverses urinary system and aorta damage in the rat due to chronic nicotine administration

We have evaluated the changes in contractile activity and oxidant damage of corpus cavernosum, urinary bladder, kidney and aorta after chronic nicotine administration in rats. The effects of melatonin on these parameters were investigated also. Male Wistar albino rats were injected intraperitoneally with nicotine hydrogen bitartrate (0.6 mg kg(-1) daily for 21 days) or saline. Melatonin (10 mg kg(-1), i.p.) was administered either alone or with nicotine injections. Corpus cavernosum, bladder and aorta were used for contractility studies, or stored with kidneys for the measurement of malondialdehyde and glutathione levels. Corpus cavernosum, bladder, and aorta samples were examined histologically and the extent of microscopic tissue damage was scored. In the nicotine-treated group, the contraction of corpus cavernosum, bladder and aorta samples and the relaxation of corporeal and aorta tissues decreased significantly compared with controls. However, melatonin treatment restored these responses. In the nicotine-treated group, there was a significant increase in the malondialdehyde levels of the corporeal tissue, bladder, kidney and aorta, with marked reductions in glutathione levels compared with controls. Melatonin treatment reversed these effects also. Melatonin administration to nicotine-treated animals caused a marked reduction in the microscopic damage of the tissues compared with those of the untreated group. In this study, nicotine-induced dysfunction of the corpus cavernosum, bladder and aorta of rats was reversed by melatonin treatment. Moreover, melatonin, as an antioxidant, abolished elevation in lipid peroxidation products, and reduction in the endogenous antioxidant glutathione, and protected the tissues from severe damage due to nicotine exposure.     

The effects of pentylenetetrazole-induced status epilepticus on behavior, emotional memory, and learning in rats

Status epilepticus (SE) can cause spatial learning, memory, and behavioral deficits; however, little information is available, especially regarding the effects of such seizures on emotional memory and learning functions. We investigated the effects of SE on emotional memory, learning, and behavior in mature rats over short and long periods. SE was induced in 50- to 60-day-old rats (P50-P60) using intraperitoneal injections of pentylenetetrazole (PTZ, n = 20); control rats received saline (n = 10). All animals were tested with elevated T-maze and open-field tests on the 1st, 7th, 14th, and 180th days after SE to evaluate emotional memory, learning, and behavior. The number of fecal boli increased, and one-way escape latency was long in a short period after SE. PTZ-induced SE causes transient memory deficits, which is related to unconditioned fear, but it did not cause any persistent abnormalities of behavior, emotional memory, and learning in mature rats.     

Could prolactin receptor gene polymorphism play a role in pathogenesis of breast carcinoma?

OBJECTIVE: Constitutive activation of various hormone and growth factor receptors is newly recognised as a common cause of tumour development. This study investigated the presence of any mutation or polymorphism of prolactin receptor (PRLR) in 38 patients with breast cancer. RESEARCH METHODS: Genomic DNA was extracted and PCR amplification was carried out for exon 1-10 of PRLR from tumoral and adjacent non-cancerous breast tissue of tumour specimens from 38 breast cancer patients. PCR products were analysed by SSCP and automatic sequencing for mutations. RESULTS: For the first time, A150C (Leu-->Ile) transversion at exon 6 of PRLR in tumour tissues, in adjacent non-cancerous breast tissues, and in blood samples of two (5.3%) out of 38 patients with breast cancer were detected. In contrast to this finding, no polymorphism of PRLR in blood samples of 100 normal individuals were found. CONCLUSION: Polymorphism of prolactin receptors might play a role in mammary carcinogenesis as a consequence of intracellular changes of PRLR signalling.