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Biomedical subjects

S Kahraman

Publications and source records attributed to S Kahraman.

At least 55 records · Page 3Linked to original sources
PubMed1999

Cervical spine injuries and management: experience with 235 patients in 10 years.

During the past 10-year period 235 patients with cervical injury were included in this study. In this paper we present our clinical experiences in patients with cervical spine injury treated surgically and conservatively and their outcome. Only few data exist on the treatment of cervical spine injuries. The principles of the management are still controversial. The 235 patients with cervical spine injury admitted to our department were assessed with Frankel's grading scale and treated surgically and conservatively according to the type and level of the injury; 172 patients were treated surgically, and 63 patients were managed conservatively. The neurological state of the patients and the treatment modality are summarized in Table 1 and Table 2. In the upper cervical injury, except type II odontoid fracture with a dislocation of more than 6 mm, conservative treatment modalities were performed. In the lower cervical injury, an anterior approach with discectomy and anterior fusion were performed if there was spinal cord compression anteriorly. Otherwise a posterior approach with decompression and a variety of posterior fusion techniques were used.

Adolescent↗
PubMed1999

Outcome analyses in 1072 surgically treated lumbar disc herniations.

This article reports the outcomes of 1072 consecutive patients surgically treated during a ten-year period. There are many new techniques for the treatment for lumbar disc hernia, but also the conventional standard discectomy procedure is still the most acceptable method today. 1072 consecutive, non-randomized patients with lumbar disc herniation were reviewed for a clinical retrospective study about the surgical outcome according to our functional grading system. The patients reported ruptured disc to be due to lifting (30.13%), trauma (9.42%), and sports (8.11%). Almost all patients had complained of radicular pain in a dermatomal distribution (90.39%) and 86.07% had low-back pain, 5.2% of the patients had complications. Eighty-five patients (7.92%) had a second lumbar disc operation. Thirty of these eighty-five patients underwent the operation at the same level. Patients were also rated to improve the ability. Almost 91% of the patients had excellent, good, and satisfactory outcome; 9% of patients had moderate and poor categories of outcome. Several conclusions can be drawn from this large series of patients who were operated for lumbar disc herniation. 1. Most patients had good-to-excellent surgical outcomes after lumbar discectomy. 2. The results of disc surgery depend not only upon operative technique and skill, the degree of neurological impairment but also upon the correct selection of cases.

Adolescent↗
PubMed1999

Fertility of ejaculated and testicular megalohead spermatozoa with intracytoplasmic sperm injection.

In this study the fertility and outcome of intracytoplasmic sperm injection (ICSI) using megalohead spermatozoa from the ejaculates and testicles was evaluated. Seventeen males with megalohead and pinhead sperm forms in their ejaculate were studied in 22 cycles. A high number of sperm heads without tails and abundant round spermatid forms were commonly observed. Round-headed spermatozoa were seldom accompanied by these severely abnormal spermatozoa. The majority of megalohead spermatozoa were observed to have multiple tails, were predominant in the sample, and were used for ICSI. Ejaculated megalohead spermatozoa were used for ICSI in 15 cycles, while testicular spermatozoa were used in seven cycles where there were no vital spermatozoa or spermatozoa of low vitality in the ejaculate. The same abnormal morphology was observed in the testicles as in the ejaculated spermatozoa in the same males. Mean (+/- SD) low motility 4.7 +/- 5.6% and sperm count (3.8 +/- 4.19 x 10(6)) were common findings in these severely teratozoospermic patients. A low fertilization rate (43.2%) was achieved by using megalohead sperm forms (group I, n = 17) in comparison with the control group (60.2%) which had zero normal sperm morphology according to strict criteria (group II, n = 30) (P <0.01). Furthermore, a low pregnancy rate (9.1%) was obtained in the megalohead sperm group in comparison with the control group (40%) (P <0.05). Low fertilization and pregnancy rates may be due to a high incidence of chromosomal abnormalities from severely defective spermatozoa in the ejaculate. Couples should be counselled and warned about possible low fertilization and pregnancy rates with ICSI when only pinhead and megalohead forms with a high number of sperm heads without tails are present in the ejaculate.

Adult↗
PubMed1998

The effect of pre-induction clonidine on platelet aggregation during minor surgery.

OBJECTIVE: This paper reports the results of a prospective randomized double-blind trial on the effects of pre-operative clonidine on platelet aggregation. METHODS: Thirty adult (ASA I-II) patients undergoing elective minor orthopaedic surgery were randomly allocated into three groups of ten patients each. In group I clonidine 2 microg x kg(-1), in group II clonidine 4 microg x kg(-1) and in group III saline placebo was administered intravenously before the induction of anaesthesia. Anaesthesia was induced with propofol and vecuronium and maintained with halothane-nitrous oxide. Platelet counts and aggregation tests were performed before (t0) and 1 h (t1) and 24 h (t24) after administration of the study drug. RESULTS: Changes in platelet counts among the groups and values over time were not significant. Both maximum rate and intensity of collagen-induced aggregation in both clonidine groups and maximum intensity of adenosine 5'-diphosphate (ADP)-induced aggregation in the high-dose clonidine group increased significantly at t1. However, all these increases in aggregation were within the normal ranges. CONCLUSION: The effects of both low and high doses of clonidine on platelet aggregation appeared to be minor, and we did not observe any increases above the normal ranges.

Adult↗
PubMed1998

Establishment and characterization of a human glioblastoma multiforme cell line.

Cell lines provide a useful system for further understanding the biology of glioblastoma multiforme. In this study, a new glioblastoma multiforme cell line, GATAGM-96 (Gulhane Askeri Tip Akademisi-Gliblastoma Multiforme-96), was established from a tumor specimen removed from an 80-year-old male patient who underwent surgery for intracranial tumor. Morphologic examination, immunocytochemical staining, growth kinetics, and karyotypic characteristics of this cell line were studied. The cytoskeleton was positive for neuron-specific enolase, vimentin, and neurofilament, and it was negative for glial fibrillary acidic protein, S-100 protein, p53 protein, epidermal growth factor, and transforming growth factor alpha. Growth kinetic studies demonstrated an approximate population doubling time of 38 to 42 h and a colony forming efficiency of 83.3%. The karyotype of the cells demonstrated it as hyperdiploid, with a large subpopulation of polyploid cells. There were numerous structural and numerical chromosome aberrations; most of them were present as clonal events. The phenotypic and chromosomal features detailed on the GATAGM-96 cell line should make it a useful addition to the cell lines currently available for in vitro and in vivo studies of glioblastoma multiforme.

Aged↗
PubMed1998

Radical surgery and reoperation in supratentorial malignant glial tumors.

The treatment modalities for gliomas are still questioning and searching. We reviewed the effect of the extent of surgical resection and reoperation on the length and quality of survival in 152 consecutive patients who underwent operation for supratentorial gliomas at GATA Neurosurgery clinic between 1985 to 1995. Seventy-two patients (50%) had glioblastoma multiforme (GBM), and 48 patients (33%) had anaplastic astrocytoma (AA). Gross total resection was achieved in 70 cases (49%), subtotal resection was performed in 60 cases (42%), and biopsy was carried out in 14 cases (9%). Thirty-two patients were reoperated for recurrency and the median interval between the first operation and reoperation was 9.5 months in glioblastoma multiforme, and 11.7 months in anaplastic astrocytoma. The resection groups were compared for age, sex, preoperative and postoperative Karnofsky rating, tumor location, postoperative radiation therapy, and chemotherapy, and survival according to multivariate analysis. Preoperative Karnofsky rating and surgical resection type were the most important factors related to survival after operation or reoperation. The gross total resection group lived longer than the subtotal resection group by life table analysis. Median survival of GBM was 76 weeks in gross total resection group, and 33 months in AA group with total resection (p < 0.001). Preoperative Karnofsky scores had a statistically significant effect on the quality of life and survival after operation and reoperation in all cases (p = 0.005). Radical surgery and reoperation also improve quality and length of life in selective malignant supratentorial gliomas.

Adolescent↗
PubMed1998

Propofol and intralipid interact with reactive oxygen species: a chemiluminescence study.

We have studied the ability of propofol and Intralipid to inhibit reactive oxygen species generated either by stimulated human leucocytes or cell-free systems using luminol chemiluminescence. Human leucocytes were stimulated by a chemotactic peptide, FMLP 1 mumol litre-1, or by a phorbol ester, PMA (protein kinase C activator) 0.1 mumol litre-1. In cell-free experiments, superoxide-hydrogen peroxide, hypochlorous acid or hydroxyl radical-induced chemiluminescence responses were initiated by xanthine 0.1 mmol litre-1 with xanthine oxidase 10 mu. ml-1, NaOCl 70 mumol litre-1 and FeSO4 3 mumol litre-1, respectively. Propofol with Intralipid, and to a lesser degree Intralipid alone, produced a concentration-dependent reduction in chemiluminescence from stimulated leucocytes. Similar attenuations were also observed using propofol with Intralipid on xanthine with xanthine oxidase-, HOCl- and ferrous iron-induced chemiluminescence. However, Intralipid produced a reduction only at high concentrations. Intralipid produced marked decreases in ferrous iron-induced chemiluminescence. This study suggests that propofol had a direct scavenging activity against HOCl, superoxide-hydrogen peroxide and hydroxyl radical in the concentrations used. These direct scavenging effects may contribute to the effect of propofol on human leucocyte chemiluminescence.

Anesthetics, Intravenous↗
PubMed1998

Multiple pregnancies obtained by testicular spermatid injection in combination with intracytoplasmic sperm injection.

Recent studies have shown that the injection of spermatid cells into the human oocyte can result in normal fertilization, embryo development and even delivery of live, healthy offspring. In our study, 23 azoospermic cases with severe spermatogenetic defects in their testicular biopsy are presented. The serum follicle stimulating hormone (FSH) concentrations and histopathological results of these males have been documented and compared in terms of fertilization and embryo development. The mean FSH value of the azoospermic males was 15.8 +/- 2.3 mIU/l, ranging from 1.6 to 39 mIU/l. Elongated spermatids were used in three cases only, as these more mature forms were mostly present in the testicular sample. In the remaining 20 cases, only round spermatids were found for use in intracytoplasmic sperm injection (ICSI). The fertilization rate with two pronuclei was 31.3%. The fertilization rate was found to be as high as 71% in three patients in the elongating and elongated spermatids group and as low as 25.6% in the round spermatid group. A few immature, non-motile spermatozoa were seen in only two cases from the elongated spermatid group. However, in the remaining cases, no spermatozoa were observed. The number of pronuclear (PN) arrest was quite high when only round spermatids were used (36.1%). Total fertilization failure was observed in two cases from the round spermatid group with Sertoli cell only and germ cell aplasia. A total of three pregnancies was achieved in 23 cases (13.0%), two from the elongated spermatid group and one from the round spermatid group. One biochemical pregnancy with a round spermatid resulted in an early spontaneous abortion and surprisingly, the remaining pregnancies were achieved with elongated spermatids resulting in multiple pregnancies. One twin and one triplet pregnancy were established following four embryo transfers in each patient. The twin pregnancy resulted in a live birth with two healthy babies; unfortunately, the triplet pregnancy ended in an abortion at 11 weeks. The use of testicular spermatids in the treatment of non-obstructive azoospermia may give hope by offering a novel treatment model. In cases with very severe spermatogenetic defect, even multiple pregnancies can be achieved with elongated spermatid cells by yielding a high implantation rate. However, the efficiency of round spermatids in achieving fertilization and pregnancy was disappointing.

Adult↗
PubMed1997

Causes of infections and management results in penetrating craniocerebral injuries.

From February 1992 to December 1994, 148 patients with penetrating craniocerebral injuries were treated surgically with primary and secondary debridement including repair of dural defects and removal of retained intracranial bone and metal fragments. Dural defects were closed primarily or with temporalis fascia, pericranium, and cadaver graft. Cerebrospinal fluid fistulas were observed in 11 (7.3%) patients; 7 of these were infected. Central nervous system (CNS) infection was seen in 2 patients without CSF fistula. Excluding those 11 patients with CSF fistula CNS infection was shown in 2 of the 137 cases (1.5%). All patients underwent CT scans periodically. In 51 (34%) of 148 patients, bone and metal fragments were determined on control CT scans. During this time, 12 patients died (8%). Most of deaths were caused by the direct effect of brain injury and occurred within the first month after injury. Fragments retained after first debridement were followed periodically by CT scan. Surgery was not performed until infection developed. Retained fragments did not increase the infection risk, but high rates of infection did occur in cases with CSF fistula.

Adolescent↗
PubMed1997

Clomiphene citrate challenge test in the assessment of ovarian reserve before controlled ovarian hyperstimulation for intracytoplasmic sperm injection.

The objective of this study is to evaluate the performance of clomiphene citrate (CC) challenge test to predict diminished ovarian reserve before controlled ovarian hyperstimulation for intracytoplasmic sperm injection (ICSI). The 198 women who underwent the CC challenge test fulfilled the following criteria; over 35 years of age, removal of one ovary or previous ovarian surgery, the presence of ovarian endometrioma or previous poor response to ovarian hyperstimulation. Of the patients tested, 141 were found to have a normal CC challenge test while 57 had an abnormal result. The cancellation rate of the cycle with a poor response was significantly higher in women with an abnormal test (36.8%) than in those with a normal test (19.8%) (P < 0.05). The sensitivity of CC test for cycle cancellation was found to be 43% with a specificity of 76%, positive and negative predictive values of 37 and 80%, respectively. The estradiol values on hCG day, the number of retrieved oocytes and metaphase II oocytes and the rate of transfer cycles were significantly lower in females with an abnormal test. Women with normal test results had higher pregnancy rates per embryo transfer than those with abnormal test results (21.5 vs. 13.3%) and the predictive value of an abnormal test for failing to conceive was 93% (53/57) with a sensitivity of 31%, specificity of 84% and negative predictive value of 15.6%. Of 57 women with an abnormal test result, 25 (43.8%) were abnormal due only to an elevated day 10 or 11 value of FSH, which could not be detected using only basal FSH screening. In this group, the cancellation rate (48 vs. 19.8%, P < 0.01), the rate of transfer cycles (48 vs. 72.3%, P < 0.05) and the mean number of retrieved oocytes (4.9 +/- 2.5 vs. 6.4 +/- 3.1, P < 0.01) were all significantly different from normal test group. Although the rate of pregnancies per started cycle (8 vs. 15.6%) did not show a statistically significant difference, this is most probably due to the low number of patients. In conclusion, an abnormal CC challenge test is a good predictor of diminished ovarian reserve and it is better than a basal FSH concentration on day 3. It provides valuable information for both patients as to their chances of achieving a pregnancy and also for the medical team deciding on options for stimulation protocols.

Adult↗
PubMed1997

Propofol attenuates formation of lipid peroxides in tourniquet-induced ischaemia-reperfusion injury.

We studied 20 adult ASA I patients undergoing elective peripheral surgery allocated randomly to one of two groups. In the propofol group (n = 9) anaesthesia was induced with propofol and fentanyl followed by continuous infusion of propofol. In the control group (n = 11), after induction of anaesthesia with thiopentone and fentanyl, anaesthesia was maintained with isoflurane. Concentrations of lipid peroxides in both plasma and muscle tissue samples were measured as thiobarbituric acid-reacting substances (TBARS). Plasma TBARS concentrations increased significantly in the control group at 1, 5, 15, 30 and 45 min after release of the tourniquet to mean 1.83 (SD 0.13), 2.00 (0.12), 2.25 (0.14), 2.30 (0.12) and 2.41 (0.14) mumol litre-1, respectively, compared with pre-reperfusion values (1.64 (0.14) mumol litre-1). In the propofol group this was significant only at 30 min (1.85 (0.03) vs 1.74 (0.04) mumol litre-1). TBARS concentrations of reperfused muscle tissue were significantly higher than pre-reperfusion concentrations in the control group (70.30(10.06) vs 52.13 (5.73) nmol/g wet tissue). We conclude that propofol attenuated ischaemia-reperfusion-induced lipid peroxidation in the therapeutic doses used in anaesthesia.

Adult↗
PubMed1997

A healthy birth after intracytoplasmic sperm injection by using immotile testicular spermatozoa in a case with totally immotile ejaculated spermatozoa before and after Percoll gradients.

Total asthenozoospermia is a severe problem, as only a micromanipulation technique can assist the couple, and even then fertilization and pregnancy rates are very low. The first healthy birth, achieved by using testicular immotile spermatozoa in a case with total asthenozoospermia before and after Percoll gradient preparation, is reported.

Adult↗
PubMed1997

Effect of abnormal sperm head morphology on the outcome of intracytoplasmic sperm injection in humans.

The present study was designed to determine the efficacy of intracytoplasmic sperm injection (ICSI) using spermatozoa with abnormal head morphology in 17 cases with total teratozoospermia. A total of 160 oocytes were retrieved and 144 metaphase II oocytes were injected. The fertilization and cleavage rates were 50.7 and 93.2% respectively. Fertilization failure occurred in two couples. A total of 54 embryos were transferred and pregnancy rates per initiated and per embryo transfer cycle were 17.6 and 20.0% respectively, while the clinical pregnancy rates per initiated and embryo transfer cycle were 11.8 and 13.3%. The implantation rate was 3.7% (2/54). Out of two pregnancies achieved, one resulted in abortion in the first trimester. The ongoing pregnancy rates per initiated and embryo transfer cycle were 5.88% (1/17) and 6.6% (1/15) respectively. Although the implantation and ongoing pregnancy rates are very low, ICSI seems to be the only treatment modality in cases where teratozoospermia was total with 100% abnormal head morphology.

Adult↗
PubMed1997

The effect of acute normovolemic hemodilution on homologous blood requirements and total estimated red blood cell volume lost.

BACKGROUND: Acute normovolemic hemodilution combined with retransfusion is one of the various techniques proposed to avoid homologous blood transfusion in cardiac surgery. The purpose of the present paper is to study the effect of the volume of autologous blood collected pre-cardiopulmonary bypass (CPB) on homologous blood requirements and total estimated red blood cell (RBC) volume lost in coronary artery bypass grafting (CABG) surgery. METHODS: Following induction of anesthesia, sequestration of one (5-8 ml/kg; Group I, n = 14) or two units (12-15 ml/kg; Group II, n = 14) of fresh autologous blood was performed under electrocardiographic and hemodynamic control. Group III (n = 14) was designated as the control group. Autologous blood was reinfused at the conclusion of CPB. RESULTS: The use of homologous blood in the study groups was significantly less than in the control group. High-volume phlebotomy did not make a significant difference in the requirement of the homologous blood, while causing a mild increase in the total estimated RBC volume lost. No significant differences could be demonstrated in preoperative, post-CPB and discharge hematocrit levels and postoperative blood drainage between the groups. CONCLUSION: Acute intraoperative hemodilution with high- and low-volume phlebotomy reduced the homologous blood requirements similarly regardless of the amount of phlebotomy.

Adult↗
PubMed1997

Outcomes of multifetal pregnancy reduction in multiple pregnancies achieved by intracytoplasmic sperm injection using ejaculated, testicular, or epididymal sperm.

OBJECTIVE: To report the pregnancy outcome after transabdominal multifetal pregnancy reduction in multiple pregnancies achieved by intracytoplasmic sperm injection. METHODS: One twin and 13 triplet pregnancies obtained by intracytoplasmic sperm injection underwent pregnancy reduction. Pregnancies were achieved with ejaculated sperm in 8, testicular sperm in 3, and epididymal sperm in 2 of these cases. All triplet pregnancies were reduced to twins at 10-12 weeks' gestation by transabdominal potassium chloride injection. A twin pregnancy with spina bifida affecting 1 fetus was reduced to singleton at 18 weeks of pregnancy. RESULTS: There was no failed procedure and no pregnancy loss within the first 4 weeks after the procedure. A complete miscarriage (7.1%) developed in 1 case at 17 weeks' gestation which was due most probably to the incompetent cervix. In utero fetal death occurred in 1 fetus of another reduced pregnancy. Three of the reduced pregnancies delivered at term, after 37 completed weeks, four premature deliveries occurred between 31 and 35 gestational weeks, and four pregnancies were ongoing beyond 25 weeks' gestation. A total of 16 fetuses, from seven twin and two singleton pregnancies, were delivered without perinatal mortality. CONCLUSIONS: Although the sample size was small, our experience indicates that the reduction of triplets obtained by sophisticated infertility treatments such as intracytoplasmic sperm injection using testicular or epididymal sperm seems to be a safe method and can be effectively used.

Abortion, Spontaneous↗