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Biomedical subjects

S Kahraman

Publications and source records attributed to S Kahraman.

At least 37 records · Page 2Linked to original sources
PubMed2003

Results of preimplantation genetic diagnosis in patients with Klinefelter's syndrome.

With the application of preimplantation genetic diagnosis (PGD), a possible genetic contribution of spermatozoa obtained from 47,XXY non-mosaic Klinefelter patients on preimplantation embryos was analysed in eight couples. Interpretable fluorescence in-situ hybridization results were obtained for 28 out of 33 embryos biopsied (84.8%) and 23 blastomeres were analysed for chromosomes 13, 18, 21, X and Y. Nine out of 23 embryos were diagnosed as abnormal (39.1%). Five out of nine contained sex chromosome abnormalities (55.5%). Two were diagnosed as 47,XXY and three were found to have monosomy X. Besides sex chromosomal abnormalities, other abnormalities detected were haploidy, triploidy, monosomy 13, monosomy 18 and trisomy 13. Five blastomeres were analysed for sex chromosomes only and all of them were found to be normal. Overall, the rate of sex chromosome abnormality in biopsied embryos was found to be 17.8% (5/28). Moreover, among 33 embryos biopsied, five of the eight zygotes, which were classified as a poor prognosis group according to pronuclear morphology scoring, showed an impaired growth profile after biopsy and were found to be chromosomally abnormal. Elimination of abnormal embyos and transfer of normal ones resulted in four pregnancies in eight cycles (50%). Two pregnancies, one singleton and one twins resulted in healthy births. Two pregnancies, one singleton and one twins are continuing beyond the second trimester. These results show that there is in fact elevated chromosomal abnormality for both sex chromosomes and autosomes in embryos developed from Klinefelter males. Furthermore together with PGD, embryo scoring according to pronuclear morphology can give additional benefit for selecting chromosomally abnormal embryos. Therefore, PGD should be recommended in cases with Klinefelter's syndrome and this information should be discussed with the couple when genetic counselling is given.

Adult↗
PubMed2003

Embryo development characteristics in Robertsonian and reciprocal translocations: a comparison of results with non-translocation cases.

The effect of translocations on embryo development was evaluated and results were compared in terms of embryo development with those of embryos obtained from standard intracytoplasmic sperm injection (ICSI) cycles. In 23 translocation carriers with 34 cycles, fertilization, pronuclear morphology scoring (PMS), developmental arrest, cleavage and blastocyst formation were evaluated and compared with embryos obtained from non-translocation cases undergoing ICSI (n = 98 cycles). In 28 cycles, preimplantation genetic diagnosis (PGD) was performed on prezygotes (first and second polar body biopsy for female carriers; n = 3) or on embryos having seven or more blastomeres (blastomere biopsy; n = 25). In six cycles for four couples, probes for translocated chromosomes were not available, so PGD could not be performed. Overall, in translocation cases, a lower fertilization rate, a higher rate of retarded embryo development, and a lower rate of blastocyst formation were observed compared with embryos of non-translocation cases. Fluorescence in-situ hybridization (FISH) analysis showed a 70.9% abnormality rate for reciprocal translocations and 55.0% for Robertsonian translocations respectively. In cases with Robertsonian and reciprocal translocation carriers, the probability of poor embryo development, which may be a result of high segregation abnormalities, may negatively affect the outcome of assisted reproductive techniques. This poor prognosis should also be considered when genetic counselling for translocation is given.

Biopsy↗
PubMed2003

Effect of mannitol in experimental spinal cord injury: an ultrastructural and electrophysiological study.

BACKGROUND: Although many experimental and clinical studies were performed on the pathophysiology and treatment of spinal cord injury (SCI), the electrophysiological and ultrastructural changes of the spinal cord were not precisely evaluated. AIMS: To investigate the effect of mannitol on Somatosensory Evoked Potentials (SSEP), postoperative neurological recovery and ultrastructural findings after an experimental SCI. SETTING: The experimental microsurgery laboratory of a university hospital. DESIGN: A prospective, randomized animal study. MATERIAL AND METHODS: Sprague-Dawley rats were used and divided into three groups (Groups I-III) for this study. Those in Group I were control animals who underwent laminectomy only, and non-traumatized spinal cord samples were obtained 2 weeks later. SCI was produced in Groups II and III using clip compression technique, and cord samples were obtained 2 weeks later. The rats in Group II received 2 g/kg of 20% mannitol intraperitoneally, immediately and three hours after trauma was induced; and those in Group III received the same amount of 0,9% NaCl in the same manner. Preoperative and postoperative SSEP records at the end of 2 weeks were obtained. Electron microscopy examination of the cord samples was done at 2 weeks postoperatively. STATISTICAL ANALYSIS USED: Fischer's Exact Test. RESULTS: SSEP records, ultrastructural findings and clinical recovery showed that minor neural damage and significant recovery occurred in Group II. CONCLUSION: This study demonstrates that the administration of 2 g/kg of 20% mannitol produces significant improvement in the neural structures and protects the spinal cord following injury.

Animals↗
PubMed2002

Pronuclear morphology scoring and chromosomal status of embryos in severe male infertility.

BACKGROUND: The study aim was to evaluate the relationship between pronuclei morphology scoring (PNMS) and the chromosomal complement of embryos in couples with severe male infertility undergoing ICSI. A total of 3116 pre-embryos was scored according to PNMS in 452 cycles. METHODS: Pre-embryos were classified into eight categories based on the alignment, size, linear or irregular distribution of pronuclear bodies (PNB), position and clarity of cytoplasmic halo and abutting of the pronucleus. These categories were subdivided into groups I and II according to the similarity and distribution of PNB. RESULTS: In total, 2574 pre-embryos formed by using ejaculated sperm, while 542 pre-embryos developed by injection of testicular sperm or round spermatids. More group II pre-embryos with markedly different morphology from group I were formed after ICSI with testicular sperm than with fresh ejaculated sperm (32.1 versus 22.7%, P < 0.01). Of 490 pre-embryos in which pronuclear morphology was evaluated, 263 were biopsied for preimplantation genetic diagnosis. The rate of chromosomal abnormality was higher in embryos developed from group II pre-embryos (52.2%) than in embryos developed from group I prezygotes (37.6%, P < 0.05). CONCLUSIONS: Group II pre-embryos had markedly different morphology from group I, and had a low rate of blastocyst formation and high risk of chromosomally abnormal embryos. When testicular sperm and round spermatids were used for ICSI, more group II pre-embryos and chromosomally abnormal embryos were produced than with ejaculated sperm. Pronuclear morphology was correlated with chromosomal complement, and impacted upon by the sperm source.

Adult↗
PubMed2001

A comparative study of three techniques for the analysis of sperm recovery: touch-print cytology, wet preparation, and testicular histopathology.

PURPOSE: The aim of this study is to evaluate the efficacy of simultaneous testicular touch-print cytology, testicular histopathology, and wet preparation in nonobstructive azoospermic (NOA) males. METHODS: Three hundred and sixty-three males with NOA underwent a multiple testicular sampling prior to ICSI for histopathologic evaluation, diagnostic testicular sperm extraction, and simultaneous touch-print cytology to evaluate sperm presence or absence. A total of 979 testicular samples were taken. RESULTS: Sperm recovery was achieved in 106 cases (29.2%). Patients with hypospermatogenesis and focal spermatogenesis needed 2.8 and 5.9 biopsies, respectively, to retrieve spermatozoa, while in patients with germ cell aplasia and maturation arrest, even after eight to nine samples no spermatozoa were recovered. Neither the FSH levels nor the testicular volume was found to be significant in the prediction of sperm recovery. If only a single testis was to be biopsied, 25% of the cases with sperm recovery would have been missed. The combination of touch-print cytology with histopathology and wet preparation increased the accuracy of spermatozoa identification. CONCLUSION: Touch-print cytology was found to be more predictive than wet preparation in the diagnosis of spermatogenesis; moreover, it was found to be a quick and easy technique providing an accurate diagnosis in prediction of sperm recovery.

Adult↗
PubMed2001

Three blastocyst stage embryo transfer resulting in a quintuplet pregnancy.

High-order pregnancies are associated with high morbidity and mortality and the incidence is increased as a drastic complication of assisted reproductive technology. This case presents a high-order pregnancy achieved by transfer of three blastocyst stage embryos resulting in a quintuplet pregnancy including a monochorionic triplet. Following the selective termination of the monochorionic triplet, two healthy children were born. The mechanism of monochorionic development and its association with assisted reproductive technology are discussed.

Adult↗
PubMed2000

Review of 36 cases of spinal cord meningioma.

STUDY DESIGN: Thirty-six consecutive patients with histologically confirmed spinal cord meningioma were presented to evaluate clinical, diagnostic, therapeutic options and to correlate treatment methods and outcome. OBJECTIVE: To present the incidence, clinical presentation, localization, techniques, and long term results of surgically treated spinal meningiomas. SUMMARY OF BACKGROUND DATA: Meningiomas are common tumors of spinal neoplasm. They are generally benign and slow-growing. Advanced in radiologic and surgical techniques have brought about better surgical results. The goal of surgical treatment must be total resection if possible. However, spinal meningiomas may recur, especially as a result of incomplete resection. METHODS: Thirty-six consecutive patients with histologically confirmed spinal meningiomas were treated from 1980 to 1997. Neuroradiological diagnosis was made through myelogram in 20 patients, CT scan in 15 patients, and MRI in 16 patients. All patients were operated on via the posterior approach and using microsurgical technique and when necessary Cooper-Ultrasonic surgical aspirator (CUSA) and CO2 laser were also applied. The patients were followed for 2 to 15 years (mean 9 years). Radiotherapy was not undertaken except in recurrent tumors. RESULTS: The most frequent site of spinal meningiomas was in the thoracic region. In 30 (83%) patients tumors were found to be completely intradural extramedullary during surgery. Total tumor resection was achieved in 35 (97%) of patients. In the follow-up period, 30 cases (83%) improved when compared to their preoperative conditions. There was one operative mortality (3%). A 66-year-old women died of pulmonary emboli. CONCLUSIONS: Magnetic resonance imaging is the best imaging technique for diagnosis. Total tumor resection improved the surgical results of spinal meningiomas. If total removal of the tumor cannot be achieved, or in the case of early recurrence followed by total resection, radiotherapy should be performed in adjuvant therapy.

Adult↗
PubMed2000

Application of syringosubarachnoid shunt through key-hole laminectomy. Technical note.

The authors describe the key-hole laminectomy technique (KHLT) for application of syringosubarachnoid shunts. This technique was used in 29 patients with noncommunicating syringomyelia. In all cases the shunts were inserted successfully without any peri- or late postoperative complications. The late follow-up magnetic resonance examinations revealed the clear collapse of syrinx in all cases. The authors advocate use of the KHLT because it is associated with less surgery-related trauma, epidural fibrosis, infection, and spinal instability.

Adult↗
PubMed2000

The relationship between genetic susceptibility to head and neck cancer with the expression of common fragile sites.

BACKGROUND: Numerous studies have recently been conducted to investigate genetic mechanisms in cancer causes and pathogenesis. Some of these studies have shown that there were certain specific chromosomal defects in normal cells of cancer patients and in their first-degree relatives. It was suggested that these individuals were susceptible to cancer development when compared with people without these defects. Materials and Methods Chromosomal anomalies, such as gaps, breaks, and acentric fragments, and fragile site expression rates were determined in peripheral blood lymphocyte cultures in 14 head and neck cancer patients, 17 first-degree relatives of these patients, and 20 healthy individuals as a control group in this study. RPMI 1640 medium, composed of aphidicolin, 5-bromodeoxyuridine, and caffeine were used for the induction of fragile sites. RESULTS: In cytogenetic and statistical evaluation, it was observed that both chromosomal aberration rates and fragile site expression frequencies in head and neck cancer patients and in their first-degree relatives were significantly greater than the control group (p <.05). It was found that fragile site expression was site specific in head and neck cancer patients and in their first-degree relatives. These specific sites were determined to be 1p21-22, 1q21, 1q25, 2q21, 2q31-33, 3p14, 16q22-23, 18q21, and 22q12 sites. CONCLUSIONS: These findings support studies showing that the fragile sites might be unstable factors in human genomes and their expression could be affected by some genetic factors, such as tumor suppressor genes and mismatch repair genes, and by some environmental factors, such as benzo (a) pyrene, dimethylnitrosamine, and dimethylsulfate. In conclusion, fragile sites may be playing an important role in the genetic tendency to head and neck cancer. Overexpression of these sites in normal lymphocytes may be used as a reliable marker to determine the genetic susceptibility in head and neck cancer patients and in their first-degree relatives.

Adult↗
PubMed2000

Calvarial metastasis of a paraganglioma. Case report and review of the literature.

BACKGROUND: Metastasis of a paraganglioma (PRG) to the calvarium is very rare. In this paper, the case of a 25-year-old male with metastasis of a PRG to the frontoparietal bone is described. CASE DESCRIPTION: The patient presented with bulging on the left side of the head, headache, and weight loss. Magnetic resonance imaging (MRI) revealed a mass lesion in the left frontoparietal region that had destroyed both the external and internal table of the bone, extending under the skin and above the dura mater. After a frontoparietal craniotomy the tumor was removed totally. Histopathological examination revealed the "Zellballen," which are pathognomonic for a PRG. Systemic examination and radiological investigation revealed no primary tumor source. CONCLUSION: Metastasis of a PRG to the calvarium is possible; radical removal of the tumor will provide a cure.

Adult↗
PubMed2000

Relationship between granular cytoplasm of oocytes and pregnancy outcome following intracytoplasmic sperm injection.

Couples undergoing intracytoplasmic sperm injection (ICSI) for male infertility using oocytes with centrally located granular cytoplasm (CLCG) were evaluated for fertilization, embryo development, implantation and pregnancy rate. CLCG is a rare morphological feature of the oocyte, that is diagnosed as a larger, dark, spongy granular area in the cytoplasm. Severity is based on both the diameter of granular area and the depth of the lesion. Twenty-seven couples with 39 cycles presenting CLCG in >50% of retrieved oocytes were evaluated. A total of 489 oocytes was retrieved, out of which 392 were at MII. CLCG was observed in 258 of the MII oocytes (65. 8%); 66.7% of these oocytes had slight and 33.3% had severe CLCG. The overall fertilization rate was 72.2% and no statistical significant difference was found between normal and CLCG oocytes and between the oocytes representing slight and severe CLCG. The development and quality of embryos was the same in normal and CLCG oocytes. In nine cycles, preimplantation genetic diagnosis was executed to evaluate a possible accompanying chromosomal abnormality. Out of 44 blastomeres biopsied, 23 had chromosomal abnormality (52. 3%). Eleven pregnancies were achieved in 39 cycles (28.2%), six pregnancies resulted in abortion (54.5%). The implantation rate was found to be 4.2%. Only five ongoing pregnancies were achieved in 39 cycles (12.8%). Couples with CLCG oocytes should be informed about poor on-going pregnancy rates even if fertilization, embryo quality and total pregnancy rates are normal. Furthermore, a high aneuploidy rate may be linked to a high abortion rate.

Abortion, Spontaneous↗
PubMed2000

Healthy births and ongoing pregnancies obtained by preimplantation genetic diagnosis in patients with advanced maternal age and recurrent implantation failure.

Preimplantation genetic diagnosis (PGD) and subsequent embryo development was evaluated in 72 couples presenting at our centre for intracytoplasmic sperm injection (ICSI) due to severe male factor. The embryo biopsies were performed in Ca(2+)/Mg(2+)-free medium. These patients were further divided into those with advanced maternal age (AMA, n = 49) and those with recurrent implantation failure (RIF, n = 23). Fluorescence in-situ hybridization (FISH) was carried out on 329 blastomeres (91.3%) with probes for the X, Y, 13, 18 and 21 chromosomes. The chromosomal abnormality rate was 41.3% with no significant difference between the AMA and RIF groups. Aneuploidy accounted for the majority (72.8%) of chromosomal abnormalities. Out of 329 embryos, 84.2% had cleaved after 24 h and 15.1% had arrested. Embryos were transferred in 70 patients and 22 pregnancies were achieved (31.4% with an ongoing pregnancy rate of 28.5%). There were no significant differences between the pregnancy rates of the AMA and RIF groups (32.5 and 30% respectively). Therefore PGD should be offered to patients with AMA and RIF. Furthermore, the use of Ca(2+)/Mg(2+)-free medium during the blastomere biopsy facilitates the procedure, while further embryo cleavage, ongoing pregnancies and healthy births are possible.

Adult↗
PubMed2000

Selective restoration of calcium coupling to muscarinic M(3) receptors in contractile cultured airway myocytes.

We previously demonstrated that after several days of serum deprivation about one-sixth of confluent cultured canine tracheal myocytes acquire an elongated, structurally and functionally contractile phenotype. These myocytes demonstrated significant shortening on ACh exposure. To evaluate the mechanism by which these myocytes acquire responsiveness to ACh, we assessed receptor-Ca(2+) coupling using fura 2-AM fluorescence imaging and muscarinic receptor expression using Western analysis. Cells were grown to confluence in 10% fetal bovine serum and then maintained for 7-13 days in serum-free medium. A fraction of serum-deprived cells exhibited reproducible intracellular Ca(2+) mobilization in response to ACh that was uniformly absent from airway myocytes before serum deprivation. The Ca(2+) response to 10(-4) M ACh was ablated by inositol 1,4,5-trisphosphate (IP(3)) receptor blockade using 10(-6) M xestospongin C but not by removal of extracellular Ca(2+). Also, 10(-7) M atropine or 10(-7) M 4-diphenylacetoxy-N-methylpiperidine completely blocked the response to ACh, but intracellular Ca(2+) mobilization was not ablated by 10(-6) M pirenzepine or 10(-6) M methoctramine. In contrast, 10(-5) M bradykinin (BK) was without effect in these ACh-responsive myocytes. Interestingly, myocytes that did not respond to ACh demonstrated robust increases in intracellular Ca(2+) on exposure to 10(-5) M BK that were blocked by removal of extracellular Ca(2+) and were only modestly affected by IP(3) receptor blockade. Serum deprivation increased the abundance of M(3) receptor protein and of BK(2) receptor protein by two- to threefold in whole cell lysates within 2 days of serum deprivation, whereas M(2) receptor protein fell by >75%. An increase in M(3) receptor abundance and restoration of M(3) receptor-mediated Ca(2+) mobilization occur concomitant with reacquisition of a contractile phenotype during prolonged serum deprivation. These data demonstrate plasticity in muscarinic surface receptor expression and function in a subpopulation of airway myocytes that show mutually exclusive physiological and pharmacological diversity with other cells in the same culture.

Acetylcholine↗
PubMed1999

Effect of diabetes mellitus on formation of coronary collateral vessels.

BACKGROUND: Although myocardial ischemia is known to be significantly related to the development of coronary collateral vessels (CCVs), there is considerable variation between patients with ischemic heart disease in the presence of collateral development. The nature of this variability is not well known. Likewise, it remains unclear whether diabetes mellitus (DM) has any effect on CCVs. The aim of this study was to evaluate the effect of DM on CCVs. METHODS AND RESULTS: Of the patients who underwent coronary angiography during the interval between March 1, 1993, and June 20, 1998, in our institution, 306 were diabetic. Those patients in whom coronary angiography is normal or severity of coronary artery stenosis is thought not to be sufficient for the development of CCVs (<75%) were excluded from the study. A total of 205 patients (mean age, 59+/-8 years) met the criteria for the DM group. For case-control matching, 205 consecutive nondiabetic patients (mean age, 58+/-9 years) who had >/=1 diseased vessel with >75% stenosis were included in the control group. The CCVs were graded according to the Rentrop scoring system, and the collateral score was calculated by summing the Rentrop numbers of every patient. There was no statistical difference between patients with and without DM in clinical baseline characteristics. The mean number of diseased vessels in the DM group (1.58+/-0.68) was higher than that in the nondiabetic group (1.42+/-0.65, P=0.005). The mean collateral score was 2.41+/-2.20 in the DM group and 2.60+/-2.39 in the control group. After confounding variables were controlled for, the collateral score in the diabetic group was significantly different from that in the nondiabetic group (P=0.034). CONCLUSIONS: Our findings suggest that CCV development is poorer in patients with than in patients without DM. Thus, we can speculate that DM is an important factor affecting CCV development.

Aged↗
PubMed1999

Effect of spent cotton stalks on color removal and chemical oxygen demand lowering in olive oil mill wastewater by white rot fungi.

Wastewater from olive oil mill was decolorized (and its chemical oxygen demand reduced in static cultivation) using the fungi Coriolus versicolor, Funalia trogii, Phanerochaete chrysosporium and Pleurotus sajor-caju. The effect of cotton stalk on decolorizing and COD removing capability was demonstrated. P. chrysosporium (in 20% medium with cotton stalk) reduced the COD by 48% and color by 58%, F. trogii (in 30% medium with cotton stalk)) by 51 and 55%, respectively.

Biodegradation, Environmental↗