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Biomedical subjects

S Yilmaz

Publications and source records attributed to S Yilmaz.

At least 55 records · Page 3Linked to original sources
PubMed2003

Laparoscopic hand-assisted living donor nephrectomy: the Calgary experience.

Laparoscopic techniques, such as hand-assisted live donor nephrectomy (HALDN), have the potential to increase the number of living kidney donors. For these techniques to be acceptable, however, the standards for donor, recipient, and graft survival achieved by the open technique need to be matched. In this study we present the results of the first 20 HALDN procedures at our center. The 20 donors included nine men and 11 women of mean (+/-SD) donor age 41 (+/-10) years and mean donor weight 78 (+/-13) kg. Mean operative time was 174 (+/-32) minutes. Only one patient required an open conversion to procedure because of venous bleeding. All kidneys were successfully implanted; there were no episodes of primary nonfunction or delayed graft function. There were no surgical complications, either in the donor or the recipient. The range of postoperative stay was 3 to 5 days. One recipient died 62 days after transplant from influenza virus pneumonia. There were no other causes of graft loss. Our preliminary results suggest that HALDN is safe and is associated with short-term donor, recipient, and graft outcomes that are at least comparable to the standard open technique.

Adult↗
PubMed2003

The effect of manganese chloride on gentamicin-induced nephrotoxicity in rats.

The aim of this study was to investigate the effects of manganese chloride on gentamicin-induced nephrotoxicity in rats. Thirty-six adult Wistar Albino rats were divided into six equal groups. They were injected with gentamicin sulfate (100 mg kg(-1) per day i.p.) and manganese chloride (2 or 20 mg kg(-1) per day i.p.) and gentamicin together with manganese chloride for 6 days. The animals were killed 24 h after the last injection. Nephrotoxicity was biochemically and histopathologically evaluated. The concentrations of creatinine, urea, sodium and potassium in plasma, malondialdehyde (MDA) and reduced glutathione (GSH) levels, glutathione peroxidase (GSH-Px) and catalase (CAT) activities in kidney tissue were determined. Administration of gentamicin to rats induced a marked renal failure, characterized with a significant increase in plasma creatinine and urea concentrations. A significant increase in kidney MDA and a decrease in GSH concentrations were observed in gentamicin-treated rats. No change was observed in the activities of GSH-Px and CAT in rats treated with gentamicin alone. Administration of the low dose of manganese (Mn2+) produced amelioration in biochemical indices of nephrotoxicity in plasma and kidney tissue when compared to gentamicin group. The histological signs of renal proximal tubules followed a similar pattern. The high dose of Mn2+ (20 mg kg(-1)) caused an opposite effect on nephrotoxicity induced by gentamicin, causing exacerbation in the tubular necrosis. The results suggest that low dose of Mn2+ may have an antioxidant effect in kidneys of gentamicin administrated rats, but its high doses had no beneficial effect.

Animals↗
PubMed2003

A comparison of the in vitro cytotoxicity of two root canal sealers.

The purpose of this study was to compare the cytotoxicity of an epoxy resin-based sealer (AH Plus) and a silicone-based sealer (Roeko Seal Automix, RSA). Cytotoxicity was assessed using the MTT assay for mitochondrial enzyme activity and haemocytometer viable cell counting after 24, 48 and 72-h exposure to L929 cells. AH Plus and RSA showed no statistically significant difference in the degree of toxicity. Both sealers had a low toxic influence on the cells during the experimental period. This study indicates that epoxy resin-based sealer AH Plus and the silicone-based sealer RSA have similar levels of cytotoxicity to mouse fibroblasts.

Analysis of Variance↗
PubMed2003

In vitro diffusion of hydroxyl ions through root dentine from various calcium hydroxide medicaments.

The purpose of this study was to determine diffusion of hydroxyl ions through dentine from different calcium hydroxide [Ca(OH)2] medicaments. Forty-five single-rooted teeth were instrumented and cavities (3 mm in diameter and 1 mm in depth) were prepared on the facial surface of each root. After smear layer was removed with 17% EDTA all surfaces of roots, except cavities, were coated with nail polish. Teeth were randomly divided into four experimental groups (each 10 samples) and a control group (five samples). They were filled with: group 1, Ca(OH)2 and distilled water mixture; group 2, TempCanal; group 3, Calasept; and group 4, Ca(OH)2 plus point. Control group, in which nothing was applied to the canals. All samples were immersed in distilled water maintained at 37 degrees C. pH values were measured at 1 h, 2 h, 3 h, 24 h, 48 h, 72 h, 4 days, 5 days, 6 days, 7 days and 14 days. Ca(OH)2-distilled water mixture and TempCanal showed highest pH values at 24 h. Calasept, Ca(OH)2 plus point and control showed highest pH values at 3 h. Time intervals after 24 h, Ca(OH)2-distilled water mixture, TempCanal and Calasept showed higher pH values than Ca(OH)2 plus point, with a statistically significant difference (P<0.05). The pH value of Ca(OH)2 plus point was lower than the values of other materials after 3 h. This study indicates that non-setting Ca(OH)2 based materials have an effective release of hydroxyl ions compared with Ca(OH)2 plus point.

Calcium Chloride↗
PubMed2003

A comparison of the oxidative stress response and antioxidant capacity of open and laparoscopic hernia repairs.

BACKGROUND: Free radical-induced lipid peroxidation that is associated with a decrease in the antioxidant status of plasma occurs in many kinds of surgical procedures. In this study, we aimed to investigate markers of oxidative stress--malondialdehyde (as thiobarbituric acid reactive substances), protein carbonyls, and protein sulfhydryls--in patients undergoing Lichtenstein tension-free hernioplasty (LH) or laparoscopic preperitoneal hernia (LPPH) repair. METHODS: Seventeen patients with unilateral inguinal hernia and no complications or recurrence were included in this study. Ten were randomized to undergo LH and seven to LPPH repair. Heparinized blood samples were taken to measure the levels of oxidative stress markers in the patients undergoing hernia repair. Levels of malondialdehyde, protein carbonyls, and protein sulfhydryls were measured preoperatively and at 6 and 24 hours postoperatively in all patients. RESULTS: Both types of hernia repair caused a significant increase in the oxidative stress response and a decrease in antioxidant activity. Plasma levels of malondialdehyde and carbonyls (indicators of oxidant activity) were significantly higher in the LH than in the LPPH repair group (P<.05), and plasma sulfhydryl levels (indicators of antioxidant activity) were significantly lower in the LH than in the LPPH group (P<.05). In both groups, significant differences were also found between the preoperative levels and the postoperative levels 6 and 24 hours (P<.05). CONCLUSIONS: These data demonstrate that both LH and LPPH repair cause a significant increase in markers of oxidative stress; however, the oxidative stress response associated with LH is greater than that associated with LPPH repair.

Antioxidants↗
PubMed2003

Use of an Innsbruck sensorimotor activator and regulator (ISMAR) in the treatment of oral motor dysfunctions: a single case report.

Many patients with cerebral palsy have difficulties during the oral preparatory phase and also during the food transport phase (swallowing), and oral-sensorimotor therapy is practised with these individuals. With oral-sensorimotor therapies, the functioning of the lips, cheeks, tongue and pharyngeal structures, and the interplay between these structures, can be improved. An Innsbruck sensorimotor activator and regulator (ISMAR) is one of the appliances used for oral-motor therapy. The purpose of this study is to describe the appliance and report a patient using ISMAR.

Activator Appliances↗
PubMed2003

The macroanatomical investigations on the aortic arch in porcupines (Hystrix cristata).

The anatomy of aortic arch in porcupine was studied. Angiography was applied to each of the three adult porcupines (two males, one female) following the injection of latex from the abdominal aorta for the examination of aortic arch. The results indicated that three arteries arose from aortic arch in porcupine. These were truncus brachiocephalicus, arteria carotis communis sinistra and arteria subclavia sinistra. The truncus brachiocephalicus in porcupine yielded arteria subclavia dextra and arteria carotis communis dextra. Truncus bicaroticus was absent. The origin of truncus costocervicalis (right) and arteria vertebralis (right) arose from a common root. Left or right axillary arteries seemed to be a continuation of subclavian arteries. The results of this study may contribute to the data in this area of science.

Animals↗
PubMed2003

Bilateral superiorly based full-thickness nasolabial island flaps for closure of residual anterior palatal fistulas in an unoperated elderly patient.

OBJECTIVE: Unoperated bilateral complete cleft lip and palate in an adult or elderly patient is seen rarely, and the existence of unoperated clefts is a result of unfavorable economic and social circumstances. We report an unoperated 65-year-old patient with bilateral complete cleft lip and palate and present our preference for the surgical management. INTERVENTIONS: Repair of the bilateral complete cleft lip and palate was successfully carried out using straight-line closure for the bilateral cleft lip and two-flap pushback palatoplasty with superiorly based lateral port control pharyngeal flap for the wide cleft palate at the first stage, and large residual anterior palatal fistulas were closed using bilateral superiorly based (retrograde flow) full-thickness nasolabial island flaps at the second stage. CONCLUSIONS: To our knowledge based on a review of the literature, this is the first report of an elderly patient with bilateral complete cleft lip and palate and the first application of bilateral superiorly based (retrograde flow) full-thickness nasolabial island flaps for closure of large residual anterior palatal fistulas or alveolar clefts. The bilateral superiorly based (retrograde flow) full-thickness nasolabial island flap may be a good solution in large anterior palatal defects using unilaterally or bilaterally in a single stage with minimal donor site morbidity, in which there is not enough tissue for local repair or if previous attempts are unsuccessful.

Aged↗
PubMed2002

Treatment outcome of adolescents with acute lymphoblastic leukemia.

Despite intensified chemotherapy, adolescents with acute lymphoblastic leukemia (ALL) still have lower rates of survival than younger children. The purpose of our study was to compare the treatment outcome and presenting clinical and laboratory features of adolescent and younger children with newly diagnosed ALL who were treated at our pediatric hematology department. Between April 1991 and February 2000, 42 children up to 18 years of age who were newly diagnosed with ALL and treated adequately with modified ALL Berlin-Frankfurt-Münster (BFM) 90 or 95 protocols were included in this study. The patients were examined in two groups according to their ages: the first group consisted of children who were <14 years old and the second group consisted of adolescents who were >14 years old. The median age of 42 patients was 6.5 years (range: 1-16.5 years); 26% of the patients were adolescents. The results of this study demonstrated that after a median observation time of 6 years the overall survival (OS) and event-free survival (EFS) of patients who were <14 and >14 years of age were 75% vs 49% and 70% vs 40%, respectively. When adolescent and younger patients were compared to each other according to gender, WBC count at administration, French-American-British (FAB) classification, immunophenotypes, risk groups, early deaths, and relapse rates, there were no statistically significant differences. Comparative data from other studies and data from this study indicate that adolescents with ALL still have shorter OS and EFS than younger children and a steady improvement in treatment outcome for adolescents with ALL over time suggests that more intensive therapy favorably influences prognosis.

Adolescent↗
PubMed2002

The effects of increased intraabdominal pressure on colonic anastomoses.

BACKGROUND: This experimental, randomized, controlled study was designed to investigate the effects of increased intraabdominal pressure (IAP) on colocolic anastomoses. To our knowledge, this is the first study to address this important issue. METHODS: For this study, 50 Wistar albino rats were randomized into five groups. The animals in all the groups underwent laparotomy and colocolic anastomosis. The rats in the control group were not subjected to increased IAP. Accordingly, IAP's of 14, 20, 25, and 30 mmHg were established by carbon dioxide insufflation and maintained for 60 min in study groups 1, 2, 3 and 4, respectively. Colocolic anastomosis was realized after these periods of IAP in the study groups. Half of the surviving rats in all the groups were sacrificed on postoperative days 7 and 14 to allow comparison between the control and study groups with respect to their mean body weights, mean anastomosis bursting pressures, and histopathologic characteristics of their anastomosis sites. RESULTS: The mean body weights of all the groups were comparable at all times during the study. The anastomosis bursting pressures of the animals subjected to increased IAP were lower than that of the control group, with the differences reaching statistical relevance for the animals subjected to an IAP of 20 mmHg or higher on postoperative day 7 (p <0.0005 for study groups 2, 3, and 4 vs the control group) and becoming more pronounced by the day 14 (p <0.0005 for study groups 2, 3, and 4 vs the control group). The anastomosis bursting pressure showed an inverse correlation with IAP. The adequacy of mucosal layer formation at the anastomosis line was lower and the degree of inflammation was higher in the groups exposed to an IAP of 20 mmHg or higher in the control group (p <0.05 for both comparisons among study groups 2, 3 and 4 vs the control group). CONCLUSIONS: An IAP increased to 20 mmHg and higher was found to result in impaired strength and wound healing in colocolic anastomoses, as reflected by the decreased bursting pressure and mucosal layer formation, and by the increased inflammation at the anastomosis sites of animals subjected to high IAP values.

Anastomosis, Surgical↗
PubMed2002

Clinical and microbiological studies of periodontal disease in Sjögren syndrome patients.

BACKGROUND: Little is known about the periodontal status of patients with Sjögren's Syndrome (SS), a chronic inflammatory autoimmune disease characterized by xerophthalmia and xerostomia. The aim of the present study was to evaluate whether the periodontal status of SS patients, in terms of clinical and microbiological parameters, differs from systemically healthy age- and gender-matched controls. METHODS: 8 primary SS and 10 secondary SS patients were examined in comparison with 11 control subjects. All patients were diagnosed by the European Community Criteria. Control subjects were systemically healthy and not undergoing periodontal treatment. The comparison of clinical status was made in terms of mean periodontal parameters (plaque index, gingival index, gingival recession, probing pocket depth, probing attachment level and bleeding on probing) as well as the frequency distribution of probing pocket depth and probing attachment level measurements. Microbiological assays of the subgingival dental plaque samples were carried out by both a chairside enzyme test (Periocheck) for the detection of peptidase activity (PA) and a polymerase chain reaction (PCR) analysis for 9 selected periodontal micro-organisms (Actinobacillus actinomycetemcomitans, Fusobacterium nucleatum, Prevotella intermedia, Treponema denticola, Porphyromonas gingivalis, Eikenella corrodens, Campylobacter rectus, Bacteroides forsythus, Streptococcus oralis). RESULTS: The occurrence, severity and extent of periodontal lesions were not significantly different between the 3 patient groups for all periodontal parameters examined. No significant differences in the sub-gingival plaque samples from control, primary or secondary SS patients for the PA test, frequency or type of periodontal micro-organisms observed. CONCLUSION: No significant differences could be detected in either clinical or microbiological parameters of primary or secondary SS patients compared with that of control subjects. The results of the present study thus support the notion that the periodontal status of patients with SS do not differ from systemically healthy age- and gender-matched controls.

Adult↗
PubMed2002

A new process for the combined treatment of municipal wastewaters and landfill leachates in coastal areas.

One of the most convenient methods for leachate control is to treat landfill leachates with domestic wastewaters. In this framework, a two-stage treatment system including anaerobic pre-treatment combined with a chemical post-treatment system such as ammonia stripping and/or Magnesium Ammonium Phosphate (MAP) precipitation can be comparable with a conventional secondary biological treatment. In this study, 2.5% and 2% of leachate by volume was mixed with domestic wastewater as the feed for the mesophilic Upflow Anaerobic Sludge Bed Reactor (UASBR). pH, feed strength and hydraulic retention time (HRT) were monitored for the evaluation of the performance of the anaerobic process. The HRT's varied from 0.76 to 0.52 d and 58% and 85% COD removal efficiencies were obtained at Organic Loading Rates (OLR) of 0.63 and 2 kg COD/m3.d respectively. The average biomass (VS) concentration in the reactor increased from 40 g/l to 50 g/l during the study. Effluents from the UASBR were further treated chemically either with lime for ammonia stripping or with MAP precipitation. MAP precipitation was applied both at the stoichiometric ratio (Mg:NH4:PO4 = 1:1:1) and above the stoichiometric ratio (Mg:NH4:PO4 = 1:1:1.3). Maximum NH4 removal of 66% was achieved at the pH of 9.3 at the stoichiometric ratio, whereas 86% NH4 removal was obtained at the pH of 9.3 above the stoichiometric ratio. Alternatively, ammonia stripping was applied either to the effluents directly taken from the anaerobic reactor or to the effluents to which MAP precipitation was applied stoichiometrically. Ammonia stripping was conducted for 24 h and 89% NH4 removal was observed at the end of 24 h. Consequently, this study indicates that anaerobic pre-treatment combined with chemical post-treatment (MAP) produced high quality of effluent comparable to the conventional biological treatment especially in terms of N and P levels.

Ammonia↗
PubMed2002

Protein C, S and antithrombin III levels in patients with acute mechanical valve thrombosis.

BACKGROUND: Mechanical prosthetic heart valve thrombosis is a serious complication with an incidence of 1-6%. The reduction in active vitamin-K dependent protein C and S levels caused by warfarin treatment also results in a prothrombotic state. This study was conducted to investigate the connection between protein C (PC), protein S (PS), antithrombin III (ATIII) deficiency and prosthetic mechanical valve thrombosis. METHODS: Twenty-nine of the 283 patients who underwent valve replacement with St. Jude medical prosthesis had mechanical valve thrombosis (group 2). The rest were considered as group 1. Twelve of the 29 patients (41.4%) had isolated aortic valve replacement, 12 had isolated mitral valve replacement (41.4%) and 5 patients had double valve replacement (17.2%). Most of the patients had rheumatic valve disease at their 1st operation. The mean time of occurrence for mechanical valve occlusion was 4.1+/-1.0 years following surgery. RESULTS: The values of PC, PS and ATIII were obtained when the mechanical valves stuck or at routine follow-up. PC, PS and ATIII levels were significantly lower in the mechanical valve thrombosis group. PC levels were 75.4+/-37.6% and 49.9+/-32.2% in group 1 and 2, respectively (p=0.001). PC, PS and ATIII values were mostly lower in the 2nd group but this difference only became significant after at least 2 years of warfarin usage. CONCLUSIONS: Natural anticoagulant levels can be low during the use of warfarin. In which case the dose can be increased in order to hold the international normalized ratio (INR) at 3-3.5. However, more frequent follow-up is required and patients should be investigated for hypercoagulation states or deficiency in anticoagulant proteins. Patients referred to hospital with any mechanical valve thrombosis or recurrent thromboembolism should be evaluated for hypercoagulant proteins.

Adult↗
PubMed2001

Viability of diced, crushed cartilage grafts and the effects of Surgicel (oxidized regenerated cellulose) on cartilage grafts.

The viability of cartilage grafts has been well documented; however, controversy still exists about the viability of crushed cartilage. Recently, there has been a tendency to use diced cartilage grafts wrapped with oxidized regenerated cellulose (Surgicel) sheets for improving dorsal contour in rhinoplasty. The viability of diced cartilage grafts and the effect of Surgicel on cartilage grafts are not well known. In this study, we used ear cartilage from 18 New Zealand rabbits. Cartilage grafts were transplanted to surgically created subcutaneous pockets on the back of the rabbits on both the left and right sides. There were three groups: (1) intact cartilage grafts, (2) crushed cartilage grafts, and (3) diced cartilage grafts. The grafts that were transplanted to the right side were wrapped with Surgicel. Cartilage grafts in all groups were viable. In grafts that were wrapped with Surgicel, a marked increase in the collagen content was investigated. Grafts that were wrapped with Surgicel demonstrated no evidence of proliferation, whereas the bare cartilage grafts demonstrated significant amounts of proliferation.

Animals↗
PubMed2001

Bilateral transpopliteal approach for treatment of complex SFA and iliac occlusions.

We present a successful case of percutaneous intentional extraluminal recanalization (PIER) of bilateral long superficial femoral artery (SFA) occlusions and a long iliac artery occlusion through ultrasound-guided retrograde popliteal artery punctures. To our knowledge, PIER of SFA occlusions via popliteal approach has been reported in only three cases, and subintimal recanalization of combined SFA and iliac occlusions has not been reported.

Aged↗
PubMed2001

Peritubular capillary basement membrane reduplication in allografts and native kidney disease: a clinicopathologic study of 278 consecutive renal specimens.

BACKGROUND: An association has been found between transplant glomerulopathy (TG) and reduplication of peritubular capillary basement membranes (PTCR). Although such an association is of practical and theoretical importance, only one prospective study has tried to confirm it. METHODS: We examined 278 consecutive renal specimens (from 135 transplants and 143 native kidneys) for ultrastructural evidence of PTCR. In addition to renal allografts with TG, we also examined grafts with acute rejection, recurrent glomerulonephritis, chronic allograft nephropathy and stable grafts ("protocol biopsies"). Native kidney specimens included a wide range of glomerulopathies as well as cases of thrombotic microangiopathy, malignant hypertension, acute interstitial nephritis, and acute tubular necrosis. RESULTS: We found PTCR in 14 of 15 cases of TG, in 7 transplant biopsy specimens without TG, and in 13 of 143 native kidney biopsy specimens. These 13 included cases of malignant hypertension, thrombotic microangiopathy, lupus nephritis, Henoch-Schonlein nephritis, crescentic glomerulonephritis, and cocaine-related acute renal failure. Mild PTCR in allografts without TG did not predict renal failure or significant proteinuria after follow-up periods of between 3 months and 1 year. CONCLUSIONS: We conclude that in transplants, there is a strong association between well-developed PTCR and TG, while the significance of mild PTCR and its predictive value in the absence of TG is unclear. PTCR also occurs in certain native kidney diseases, though the association is not as strong as that for TG. We suggest that repeated endothelial injury, including immunologic injury, may be the cause of this lesion both in allografts and native kidneys.

Basement Membrane↗
PubMed2001

Anteroposterior diameter of the vertebral canal in cervical region: comparison of anatomical, computed tomographic, and plain film measurements.

The purpose was to compare the computed tomographic and plain film measurements with those of anatomical specimens to determine the antero-posterior diameter of the spinal canal in cervical region. Antero-posterior diameters of 75 cervical vertebral canals (15 sets of C3-C7) were measured anatomically at two different levels. Computed tomographic and plain film measurements were also obtained at the corresponding levels. Considering anatomical measurements as the gold standard, plain film and computed tomographic measurements were statistically compared. Interobserver and intraobserver differences were also evaluated. At the uppermost pedicle levels, there was no statistically significant difference between plain films and anatomical measurements, a good correlation. However, at lowermost pedicle level there was a statistically significant difference between plain films and anatomical measurements but not between tomographic and anatomical measurements. Our results suggest that plain films can accurately estimate cervical spinal canal mid-sagittal diameter at the uppermost pedicle level and be used as a first step examination for the evaluation of cervical spinal stenoses.

Anthropometry↗