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Biomedical subjects

S Yildiz

Publications and source records attributed to S Yildiz.

At least 37 records · Page 2Linked to original sources
PubMed2002

Progesterone profiles of fat-tailed tuj ewes following tactile and visual separation of rams at the beginning of the breeding season.

The aim of this study was to determine the level and duration of progesterone secretion during the sequential oestrous cycles in fat-tailed Tuj ewes following tactile and visual separation of rams during the breeding season. For these purposes, rams were separated from the main flock for 50 days starting from the beginning of the breeding season and 21 ewes were randomly selected for the current experiment. In order to assess luteal activity and the length of oestrous cycles, the ewes were blood-sampled thrice or twice weekly for the measurement of progesterone in plasma. The data showed that 3 +/- 0.2 oestrous cycles were observed in this time window, and the first oestrous cycle observed was shorter (P < 0.05) than the following cycles (mean +/- SEM, 14.6 +/- 0.82, 16.5 +/- 0.48 and 17.0 +/- 0.54 days, respectively, for cycles 1, 2 and 3). Progesterone production was significantly lower in the first oestrous cycle compared with the second and third cycles on days 9, 12 and 14 of the cycles. The follicular periods of ewes showed four accumulations (maximum values using a 3-day moving average technique) throughout the study and the percentages of ewes at each accumulation (peak day +/- 1 day) were 50, 35, 65 and 80% for the first, second, third and fourth accumulations, respectively (P < 0.05). It was concluded that progesterone production was lower and the oestrous cycles were shorter during the first oestrous cycle and that tactile and visual separation of rams at the beginning of the breeding season might enhance the synchronizing effect towards the end of the breeding season in the fat-tailed Tuj ewes.

Animals↗
PubMed2002

Effect of medetomidine-butorphanol-ketamine anaesthesia and atipamezole on heart and respiratory rate and cloacal temperature of domestic pigeons.

The purpose of this study was to evaluate the sedative-anaesthetic effects of a combination of medetomidine (M, 50 microg per pigeon), butorphanol (B, 50 microg per pigeon) and ketamine (K, 25 mg per pigeon) in domestic pigeons. Eight domestic pigeons (four male and four female, 8-15 months old) were used. The combination of Medetomidine and butorphanol injectable solutions were used to produce sedation. Ten minutes after M + B administration, K was injected. The anaesthetic effects of the drugs were reversed by administration of Atipamazole (AT) at 60 min after K administration. All drugs were injected into the pectoral muscles. The sedative-anaesthetic effects of the M + B-K combination and, alterations in respiratory rate (RR), heart rate (HR), electrocardiographic (ECG) findings and cloacal temperature (CT) were investigated before and 10 min after pre-medication with M + B, at 5, 15, 30, 45 and 60 min during the onset of K anaesthesia and at 1, 5, 10, 20, 30 and 60 min following the administration of AT. The HR and RR of pigeons decreased within 10 min following M + B administration and remained lower until 1st and 5 min of AT injection, respectively. In ECG, no significant alterations in P, Q, R and S-values were observed, however, arhythmia was recorded for three pigeons, which returned to normal values following AT administration throughout the measurement. Cloacal temperature decreased gradually during the anaesthesia from 41.0 to 32.7 degrees C. The drug combination used in this study produced a satisfactory general anaesthesia for seven of the eight pigeons. All pigeons were unconscious within 5 min after K administration as indicated by disappearance of the palpebral and corneal reflexes and lack of reaction to the pain stimuli during the study. The effect of AT administration was observed within 10 min as all pigeons responded partly against stimuli and all reflexes. It is concluded that M + B-K anaesthesia in pigeons is a safe and reliable anaesthetic protocol for surgery.

Adrenergic alpha-Antagonists↗
PubMed2002

Effects of palm oil on lipid peroxidation, reduced glutathione, glutathione peroxidase, and vitamin A levels in the corpus uteri, cornu uteri and corpus luteum of young and adult female sheep.

The aim of the current study was to determine whether a rumen protected palm oil based diet affect malondialdehyde (MDA), glutathione peroxidase (GSH-Px), reduced glutathione (rGSH) and vitamin A levels in the tissues of cornu uteri, corpus uteri and corpus luteum over the barley based isoenergetic and isonitrogenous diet, and whether the response is different between ewes and ewe-lambs. During the breeding season, half of Morkaraman ewes (2-4-year-old, n = 10) and ewe-lambs (7-8-months-old, n = 10) was offered a barley based diet and the other half was offered a protected palm oil based diet for 42 +/- 0.7 days. At the end of the experiment all animals were slaughtered and measurements carried out in the tissues collected. In all animals tested, cornu uteri had the highest MDA levels followed by corpus uteri and corpus luteum (P < 0.01) but no differences were between the tissues observed in GSH-Px and rGSH levels (P > 0.05). Vitamin A levels were, however, higher in corpus luteum than in cornu uteri and corpus uteri (P < 0.05). Corpus uteri MDA levels were not different (P > 0.05) but rGSH levels were higher for the palm oil fed groups (P < 0.05). GSH-Px and rGSH levels were higher for ewe-lambs than ewes (P < 0.05). In conclusion, it appears that MDA, rGSH, GSH-Px, and vitamin A work in a different fashion for corpus uteri, cornu uteri and corpus luteum, and for ewes and ewe-lambs. Dietary palm oil did not significantly affect the parameters studied except higher rGSH levels in corpus uteri. Levels of antioxidatively active substances, such as rGSH and GSH-Px were lower in ewes compared with those in ewe-lambs.

Animals↗
PubMed2001

Evaluation of internal behaviors of children with congenital heart disease.

This study was designed to determine how internal behaviors of children with congenital heart disease were handled by their mothers. The study group included the mothers of 96 children randomly selected (ages ranging from 4 to 11 years) who were being monitored at the Institute of Cardiology. A 21-item questionnaire was administered to obtain information about the mother and the child. Internal subsets of the Child Behavior Check List (CBCL)/4-18 were performed, including withdrawn aggressive behaviors, somatic complaints, and anxiety/depression tests. The results showed that factors influencing withdrawn aggressive behavior were low parent education (p =.000), poor economic status of the family (p =.02), and aggravation of the hemodynamic status of the disease (p =.003). The factors influencing somatic complaints were low parent education (p =.000) and severity of the hemodynamic status of the disease (p =.02). An increase in the number of children in the family seemed to have an effect on anxiety/depression levels (p =.009).

Adolescent↗
PubMed1999

The effects of experimental varicocele on testicular histology and fertility in monorchic adult rats.

OBJECTIVE: To determine the effects of a left-sided experimental varicocele on testicular morphology and fertility in right hemicastrated adult rats. MATERIALS AND METHODS: A double-controlled experimental study was carried out using mature Sprague-Dawley rats, with 12 rats in each treated group and five corresponding controls. Group 1 underwent right orchidectomy, group 2 right orchidectomy and a left varicocele, and group 3 only a left varicocele; each control group underwent a corresponding sham operation. Two months after surgery each rat was placed with two mature female rats for one month to assess fertility. All the rats were then killed and their testes weighed; the mean testicular weight was calculated for each group and the mean seminiferous tubule diameter (STD) measured. Johnsen scores and histological abnormalities were evaluated for each testis using light microscopy. RESULTS: The mean (SEM) testicular weight and STD in group 2 were significantly lower, at 1311 (100) mg and 225 (11) microm, respectively, than in group 1, at 1771 (28) mg and 255 (4) microm (P<0.05). The mean weights of both testes in rats in group 3 were significantly lower than those in group 1 (P<0.05) and although both mean STDs were less than in group 1, the differences were not significant (P>0.05). There were no differences between the Johnsen scores in groups 2 and 3. There were severe histological abnormalities in the left testes in three of nine and two of eight animals in group 2 and 3, respectively; in group 3, changes in the right testis were detected in one rat. Six of nine and seven of eight rats were fertile in group 2 and 3, respectively. CONCLUSION: Experimental left varicocele decreased the left testicular weight and STD in both hemicastrated and intact adult rats. However, the presence of the right testis is important for preserving fertility.

Animals↗
PubMed1999

Voiding and sexual dysfunctions after pelvic fracture urethral injuries treated with either initial cystostomy and delayed urethroplasty or immediate primary urethral realignment.

OBJECTIVE: The aim of this study is to evaluate the effects of the different immediate treatment modalities on the sexual and voiding functions in pelvic fracture urethral injuries. METHODS: The records of 38 male patients with traumatic posterior urethral injuries were reviewed, 18 of whom were treated by initial suprapubic cystostomy and delayed repair (Group 1), and 20 by primary urethral realignment (Group 2). Types of pelvic fractures and urethral injuries were classified according to surgical and radiological findings. Long-term voiding functions were determined by the patient questionnaire, residual urine and uroflow. Sexual functions were also determined by the patient questionnaire and a penile duplex ultrasound study. RESULTS: Mean follow-ups of Groups 1 and 2 were 37 and 39 months, respectively. Membranous urethral disruption extending to the urogenital diaphragm was the most frequent urethral injury (type 3), with incidences of 66.7% and 77.7%, respectively. There were no statistically significant differences in mean age, incidence of pelvic fracture types and urethral injury types between groups (p > 0.05). After the immediate treatments, 16.7% and 55% of the patients regained normal urination, and stricture developed in 83.3% and 45% of the patients, respectively. In 44.4% of the patients in Group 1 and 10% in Group 2, urethral strictures required open urethroplasty (p < 0.05). Erectile impotence before urethroplasty in 17.6% and 20%, anejaculation after urethroplasty in 17.6% and 15% and incontinence in 5.6% and 10% of the patients were found in Groups 1 and 2, respectively (p > 0.05). However, 88.8% and 90% of patients eventually achieved normal urination with complete continence. CONCLUSION: Sexual and voiding dysfunction after pelvic fracture posterior urethral injury seem to be the result of the injury itself, not of the immediate treatment modalities. In urethral disruption injuries, primary urethral realignment seems more favourable than suprapubic cystostomy and delayed repair.

Adolescent↗
PubMed1998

The outcome of varicocelectomy in subfertile men with an absent or atrophic right testis.

OBJECTIVES: To determine the effects of varicocelectomy on semen quality, testicular volumes and serum hormone levels in subfertile men with an absent or atrophic right testis. PATIENTS AND METHODS: Seventeen patients whose wives were gynaecologically normal were evaluated with at least two semen analyses and measurements of serum hormone levels and antisperm antibodies. Scrotal ultrasonography was used to determine testicular volumes and spermatic vein diameters. Varicocelectomy was performed by high ligation via an inguinal approach. All patients were seen at a follow-up 3 months later, and after 6, 9 and 12 months the scrotal ultrasonography, hormone assessment and semen analyses were repeated. Any pregnancies in their wives were recorded over a median follow-up of 19 months. RESULTS: After surgery, all patients had significant improvements in sperm motility, morphology and concentration (P<0.01) but the differences in pre- and post-operative testicular volumes and plasma hormone levels were not statistically significant (P>0.01). No patients had immunological infertility. Eleven of the wives became pregnant during the follow-up. CONCLUSION: Higher pregnancy rates can be achieved by left varicocelectomy in subfertile men with an absent or atrophic right testis. Sperm concentration, motility and morphology are significantly improved by varicocelectomy.

Adolescent↗
PubMed1998

Fournier's gangrene: risk assessment and enzymatic debridement with lyophilized collagenase application.

OBJECTIVES: Fournier's gangrene (FG) is an abrupt, rapidly progressive, gangrenous infection of the external genitalia, perineum or abdominal wall and is a real urologic emergency. In this study, the risk factors of FG and the effects of enzymatic debridements on wound healing were investigated. PATIENTS AND METHODS: We reviewed the records of 34 patients with FG to investigate the possible correlation between clinical outcome and infection focus, patient age, number of types of bacteria cultured, delay until presentation, predisposing diseases or accompanying conditions such as diabetes, neurologic deficit, chronic alcoholism and renal failure. Broad-spectrum triple antimicrobial therapy, aggressive and frequent surgical debridement, and if necessary urinary and colonic diversions were performed to control the infection. The effects of enzymatic debridements with topical lyophilized collagenase applications on the wound healing after the control of active infection were evaluated. RESULTS: The average age of the patients was 55 years. The sources of infections were urogenital in 12 (35.3%), anorectal in 10 (29.4%), dermal in 10 (29.4%) and undetermined in 2 (5.8%) of the patients. The average presentation time was 4.4 days and the number of isolated bacteria was 3.05 per case. The number of isolated bacteria and surgical debridements, the duration of hospital stay and the rate of mortality in patients with anorectal foci were higher than those of the patients with urogenital or dermal foci (p < 0.05). Diabetes, uremia and advanced age did not significantly affect the number of surgical debridements, the duration of hospital stay and control of active infection. Mortality was increased in chronic alcoholism, a finding of undetermined significance. Enzymatic debridements decreased the duration of hospital stay (p < 0.05). Five patients (14.7%) died despite prompt medical and surgical preventive measures. CONCLUSION: Chronic alcoholism, anorectal infection foci, neurological deficit and delayed presentation were found as risk factors in FG. Diabetes and advanced age did not affect the progression of disease in our cases. Enzymatic debridements decrease the number of surgical debridements and the duration of hospital stay.

Adolescent↗
PubMed1997

Effects of intracavernous calcium channel blockers in dogs.

Intracavernous injection of smooth muscle relaxing agents can induce penile erection. In this experimental study, we compared the effects of intracavernously injected calcium channel blockers (CCBs) and papaverine in dogs, and investigated their clinical applicabilities. We administered 30 mg papaverine, 10 mg nifedipine, 10 mg nitrendipine and 2.5 mg verapamil to 10 adult male dogs intracavernously, each at different times. Intracavernous pressure values, systemic arterial pressure values and heart rate values were recorded for 45 minutes after the intracavernous injections. We used the paired Student t-test for statistical analysis. Papaverine induced full erection in all of the 10 dogs. Nifedipine induced full erection in 4, nitrendipine in 5, and verapamil in 6 of the 10 dogs. Nifedipine and nitrendipine caused significant decreases in blood pressure and increases in heart rate. In conclusion, the effects of intracavernous CCBs are not superior to those of papaverine. We cannot recommend nifedipine and nitrendipine for intracavernous injection, but verapamil may be included in intracavernous pharmacotherapeutic combinations.

Animals↗
PubMed1997

[Neostigmine and edrophonium. Antagonism of profound and shallow mivacurium blockade].

UNLABELLED: Mivacurium has a short duration of action because it is rapidly hydrolysed by plasma cholinesterase. There is ongoing controversy concerning the antagonism of mivacurium-induced neuromuscular block, firstly because of its short spontaneous recovery time, and secondly because the metabolism of mivacurium may be inhibited by anticholinesterases. We therefore compared neostigmine and edrophonium reversal of deep and moderate mivacurium-induced blocks. METHODS: After approval by the local ethics committee, 48 ASA class I and II adult patients were investigated during nitrous oxide-fentanyl-thiopental anaesthesia using train-of-four (TOF) stimulation and monitoring of the isometric force of adduction of a thumb. The patients received 0.2 mg/kg mivacurium i.v. Neuromuscular transmission was allowed to recover spontaneously in 10 patients (group SP). In 2 other groups the neuromuscular block was antagonised by administration of 0.04 mg/kg neostigmine (group N5; n = 9) or 1.0 mg/kg edrophonium (group E5; n = 10) when T1 had recovered spontaneously to 5% of control. In two other groups the neuromuscular block was antagonised with the same doses of neostigmine or edrophonium in 10 patients (group N25) and 9 patients (group E25), respectively, when T1 had recovered spontaneously to 25% of control. RESULTS: Neostigmine or edrophonium administered when T1 had recovered spontaneously to 25% of control shortened the recovery time (time from administration of ant-agonist to a T4/T1-ratio of 0.7) significantly from 10.7 +/- 2.2 min (mean +/- SD) in the SP group to 5.1 +/- 2.0 and 5.3 +/- 1.5 min in the N25 and E25 groups, respectively (P < 0.05). The corresponding recovery times in the SP, N5, and E5 groups were 15.9 +/- 2.9, 10.0 +/- 1.9, and 7.7 +/- 2.2 min, respectively. The difference between the SP and E5 groups was significant (P < 0.05). The recovery indices (time from 25% to 75% recovery of T1) of 3.0 +/- 1.3 and 1.7 +/- 0.9 min for the E5 and E25 groups, respectively, were shorter than those of the SP group at 6.1 +/- 2.0 min (P < 0.05). CONCLUSIONS: Two theoretical reasons, the very rapid onset time and the fact that it does not inhibit plasma cholinesterase, suggest edrophonium to be the preferred antagonist of a mivacurium-induced blockade. These two characteristics are reflected in our results: only edrophonium was able to shorten the recovery index significantly and, administered at a profound level of mivacurium-induced neuromuscular block, only edrophonium was successful in shortening recovery time significantly. Therefore, edrophonium should be the anticholinesterase of choice to antagonise a mivacurium-induced neuromuscular block.

Adolescent↗
PubMed1996

Intraobserver and interobserver reproducibility of WHO and Gleason histologic grading systems in prostatic adenocarcinomas.

In this study a total of 96 patients with prostatic carcinoma were evaluated retrospectively. Sections prepared from paraffin blocks were examined and all cases were scored according to the World Health Organization (WHO) and Gleason grading systems. We investigated intraobserver and interobserver reproducibility of two grading systems in prostatic adenocarcinomas. In our study the intraobserver reproducibilities of the WHO and Gleason systems were 75.0% and 78.1%, respectively. The interobserver reproducibilities of the WHO and Gleason grading systems were 60.4% and 70.8%, respectively. While there was no difference between intraobserver and interobserver variations in the Gleason system (p > 0.05), there was significant difference between intraobserver and interobserver variations in the WHO system (p < 0.05).

Adenocarcinoma↗
PubMed1996

[Plasminogen activator inhibitor 1 and prognosis in breast carcinoma].

The proteolytic enzyme urokinase-type plasminogen activator (uPA) plays an important role in degrading extracellular matrix. This seems to be an important step in cancer invasion and metastasis. uPA antigen levels correlate significantly with disease recurrence and death in breast cancer. To build up tumour stroma in primary tumours as well as in metastases, inhibition of proteolytic activity is necessary. In this study we investigated the correlation of the Plasminogen Activator Inhibitor 1 (PAI-1), which is the specific inhibitor of uPA and which seems to be important for tumour formation, with prognosis in breast cancer. PAI-1 antigen levels were measured in cytosols of 268 primary breast cancers. In 205 cases we correlated the PAI-1 status (cut-off value: 1 ng/mg) with the clinical outcome. Furthermore we investigated PAI-1 antigen levels in 10 benign breast tumours and 33 metastases. PAI-1 levels were significantly higher in primary carcinomas (median value: 0.62 ng/mg, range: 0 to 30.7) than in benign tumours (median value: 0 ng/mg, range: 0 to 0.1) and metastases showed elevated levels (median value: 1.05 ng/mg, range: 0 to 7.8) in comparison to the primary tumours (Kruskal-Wallis test: p < 0.05). We found that the PAI-1 status correlated significantly with early disease recurrence (Mantel-Test p = 0.0069) and overall survival (Mantel-Test p = 0.0121). After a median follow-up of 32 months (range 2-58), 36% of patients with PAI-1 antigen levels > or = 1 ng/mg (n = 72) showed an early relapse and 24% died, whereas only 19% of patients with PAI-1 antigen levels < 1 ng/mg (n = 133) relapsed and 9% died within the study period. A multivariate analysis revealed that in our study population PAI-1 is not an independent prognostic factor. According to our findings PAI-1 seems to be involved in the formation of extracellular matrix in primary carcinomas and metastases and is related to poor prognosis in breast cancer.

Adult↗
PubMed1995

Total knee arthroplasty complicated by Corynebacterium jeikeium infection.

Corynebacterium jeikeium is a slow-growing multiresistant micro-organism. It causes serious opportunistic infections in patients with long hospital stays who receive broad-spectrum antibiotics. It can be isolated from blood and other sites in neutropenic, immunosuppressed bone marrow recipients and in patients with indwelling catheters. Cases of infection related to bone and joint replacements are rare. This case is the first where Corynebacterium jeikeium has been isolated from an infected knee following total knee arthroplasty.

Aged↗
PubMed1995

Sonourethrography in anterior urethral stricture: comparison to radiographic urethrography.

Twenty-three male patients with known or suspected urethral stricture disease were evaluated using sonourethrography and standard retrograde x-ray urethrography for comparative analysis of two techniques. Results were evaluated statistically. These two methods can substitute each other in determining the stricture area length of anterior urethra. Due to advantages, if both of these methods are used combining each other, we believe that they will be much more sensitive.

Adult↗
PubMed1987

Scanning electron microscopy of circulating platelets reveals new aspects of platelet alteration during cardiopulmonary bypass operations.

Seventeen male patients undergoing cardiopulmonary bypass (CPBP) surgery for aorto-coronary bypass grafting were investigated by scanning electron microscopy (SEM) for alterations of the surface morphology of circulating platelets. An initial decline in the percentage of unactivated smooth discocytes (SD) to 87 +/- 12% was found after thoracotomy. Three minutes after the onset of CPBP, the percentage of SD had dropped drastically to 59 +/- 13%, and by the 8th minute of CPBP it had dropped to its lowest point (49 +/- 19%). On the other hand, the percentage of shape-changed platelets (SC) increased to 17 +/- 9% after 3 minutes, and the percentage of pseudopod discocytes (PD) to 25 +/- 13% after 8 minutes. Surprisingly, a remarkable recovery of platelet morphology could be observed after even 15 minutes of CPBP, and by the end of bypass 78 +/- 15% of the circulating platelets had regained the smooth discoid (SD) appearance of unactivated platelets. We conclude that this recovery of platelet morphology is due to an increasing insensitivity of the platelets to activating stimuli during the course of CPBP. Our study provides evidence that the only major platelet activation occurs during the first minutes of CPBP, and that CPBP-caused platelet activation is much less pronounced than generally believed.

Journal Article↗