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Biomedical subjects

S Ozkan

Publications and source records attributed to S Ozkan.

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

Effect of different neoadjuvant chemotherapy regimens on locally advanced breast cancer.

In this retrospective study, we evaluated the results of 91 locally advanced breast cancer (LABC) patients (30 patients in stage IIIA - 33.0%, 61 patients in stage IIIB - 67.0%) who had been treated with different neoadjuvant chemotherapy regimens. Forty-three (47.3%) patients treated with FAC (5-Fluorouracil, doxorubicin, cyclophosphamide) or CA (cyclophosphamide, doxorubicin), 33 (36.3%) with FEC (5-Fluorouracil, epirubicin, cyclophosphamide) or CE (cyclophosphamide, epirubicin) and 15 (16.5%) with CMF (cyclophosphamide, methotrexate, 5-Fluorouracil) combination as neoadjuvant setting. Median follow-up duration was 33 (6-116) months in 91 patients. There was no significant difference in the pretreatment characteristics of patients receiving FAC/CA, FEC/CE and CMF including age, disease stage, menopausal and estrogen/progesteron receptor (ER/PR) status (p>0.05). In CMF group, no patient was treated with taxan as adjuvant setting. However, ten patients (30.3%) in FEC/CE group and 21 patients (48.8%) in FAC/CA group were treated with taxans. Overall response rate was lower in CMF group (60.0%), when compared to FEC/CE (81.9%) and FAC/CA (91.0%) groups (p<0.05). Median overall survival (OS) and diseases free survival (DFS) were similar in three groups; 28.0 months (range: 14.8-41.1) and 12.0 months (range: 5.3-18.6) in CMF, 45.0 months (range: 16.8-73.1) and 23.0 months (range: 0.0-48.6) in FEC/CE, 46.0 months (range: 41.1-50.8) and 22.0 months (range: 11.1-32.8) months in FAC/CA groups, respectively (p>0.05). In conclusion, overall response rates were found to be higher in anthracycline-based combinations than CMF, but these regimens had no additional survival advantage over CMF regimen. Long-term effects of these regimens should be investigated in further randomized trials.

Adenocarcinoma↗
PubMed2003

[Results of inferior oblique muscle surgery in superior oblique paralysis].

The aim of this study was to evaluate the results of inferior oblique muscle recession in certain cases of superior oblique paralysis. Twenty-three patients with moderate hyperaction of the inferior oblique muscle, secondary to paralysis of the superior oblique muscle, in whom a recession of the ipsilateral inferior oblique was applied were enrolled in this study. These cases were selected among those with congenital superior oblique paralysis and infantile nontraumatic paralysis and those of unknown origin. Isolated recession of the inferior oblique muscle achieved a mean decrease in 8.69 +/- 2.05 D in hypertropia in the primary position. In 19 cases out of 23 (82.6%) who received isolated recession of the inferior oblique muscle, a vertical deviation equal to or less than 4 PD was obtained, showing the efficacy of this method in the surgical treatment of the cases with superior oblique paralysis and a moderate inferior oblique hyperaction.

Adolescent↗
PubMed2002

Hospital-acquired infections following the 1999 Marmara earthquake.

In this study, medical records of all casualties admitted to our hospital following the Marmara earthquake, which struck northwest Turkey and resulted in the destruction of several towns in the Marmara region, were evaluated retrospectively. The time buried under the rubble, demographic data, type of medical and surgical therapies performed, type of injury and data on infection were analysed. Between 17 August and 25 September 1999, 630 trauma victims were received at our hospital and 532 (84%) of them were hospitalized. The mean age of hospitalized patients (312 males, 220 females) was 32 years (2-90 years). Two hundred and twenty patients were hospitalized for more than 48 h. Forty-one of them (18.6%) had 43 hospital-acquired infection (HAI) episodes, which were mostly wound infections (46.5%). A total of 143 culture specimens was collected and 48 yielded the following potential pathogens: 15 Acinetobacter baumanii (31.2%), nine Staphylococcus aureus (18.7%), seven Pseudomonas aeruginosa (14.6%), six Escherichia coli (12.5%), six Klebsiella pneumoniae (12.5%), two Stenotrophomonas maltophilia (4.2%) and three various Pseudomonas spp. (6.3%). All S. aureus strains were found to be resistant to methicillin in vitro. Two strains of A. baumannii and one P. aeruginosa were found to be resistant to all antimicrobials including carbapenems. Fifty-three victims died (10%) and 36 of those died during the first 48 h because of severe injuries and multi-organ failure. After 48 h of hospitalization, the mortality rate was significantly higher in those patients with HAI (14/41) than those without (3/179) (34.1% vs. 1.7%, P<0.05). In conclusion, trauma is the significant factor associated with HAI and a high incidence of Acinetobacter strains was responsible for HAI in trauma patients.

Acinetobacter↗
PubMed2002

The development of thermal resistance of the feather coat in broilers with different feathering genotypes and feeding regimes.

1. This study compared the development of thermal resistance of the feather coat in broilers, with early or late feathering genes, and with or without the naked neck gene, allowed ad libitum or restricted feeding. 2. Male and female broilers of one of the 4 genotypes were reared to 6 weeks of age and allocated to one of the two feeding regimes. The thermal resistance of the back and crop region was measured at weekly intervals. A sample of birds were killed at the same ages and total feather weight, primary and secondary flight feather weight, liver weight and abdominal fat weight were measured. 3. All three main factors, sex, feeding and genotype, had significant effects on feather weight over time. The primary and secondary flight feathers were less affected by feed restriction than the feather coat as a whole. Birds with the naked neck gene showed a greater depression in growth rate than birds with a normal neck under conditions of restricted feeding. 4. The thermal resistance of the feathers on the back was greater in females, increased by early feather growth and decreased by restricted feeding. 5. Relative to metabolic body size, birds on restricted feeding had a greater feather weight and a smaller liver. There was a marked reduction in fat deposition, to almost negligible levels by 6 weeks of age. 6. Broilers given restricted feeding, in preparation for breeding, would benefit by a warmer environment, particularly those with feathering genotypes which confer a lower thermal resistance.

Adipose Tissue↗
PubMed2002

Comparison of the therapeutic efficacy of 4-methylpyrazole and N-acetylcysteine on acetaminophen (paracetamol) hepatotoxicity in rats.

Obtaining effective analgesia with a minimal erosive effect on gastric mucosal tissue has increased the consumption of acetaminophen (paracetamol), especially among the elderly. However, the hepatotoxic effects of acetaminophen have also increased. We aimed to compare the effects of 4-methylpyrazole (4-MP), N-acetylcysteine (NAC) and their combined use on the hepatotoxicity of acetaminophen in a rat model. Male Wistar Albino rats were divided into six groups. Groups 1-5 received 2,000 mg/kg acetaminophen by gavage while the control group was group 6. Group 2 animals were given NAC (loading dose 140 mg/kg followed by seven doses at 4 h intervals); group 3 received 50 mg/kg 4-MP; group 4 received 200mg/kg 4-MP; and group 5 received NAC as in group 2 plus 200 mg/kg 4-MP. Blood samples were taken for measurements of serum AST and ALT levels. The livers of the rats were removed for microscopic examination and grading of hepatic necrosis. AST and ALT levels in groups 2-5 were lower than that of group 1 (p < 0.001), although no significant difference was noted between groups 2-5 (p > 0.05). Higher levels of ALT were found in group 5 than in group 2 (p < 0.05), and higher levels of AST were found in group 5 than in group 3 (p < 0.01). Median necrosis scores were 3.36 for rats receiving acetaminophen alone (p < 0.001, compared with groups 2-6), 1.45-1.81 for groups 2-5 (p > 0.05, compared with each other), and 0.18 for control rats (p < 0.001, compared with groups 1-5). In conclusion, the administration of 4-MP and/or NAC after 4 h of administering toxic dose of acetaminophen, inhibits hepatotoxicity in rats. There was no difference between the 4-MP and NAC-treated groups as reflected by comparable levels of serum transaminases and the degree of hepatic necrosis. Combining of 4-MP and NAC offers no benefit.

Acetaminophen↗
PubMed2002

Cerebral blood flow velocity changes to visual stimuli in patients with multiple sclerosis.

We assessed the blood flow velocity (BFv) changes to visual stimuli using transcranial Doppler (TCD) in patients with multiple sclerosis (MS) during an exacerbation period by means of vasoneuronal coupling. Eighty-four patients (19 men, 75 women) and 45 healthy subjects (14 men, 31 women) were studied. Both posterior cerebral arteries (PCAs) were simultaneously monitored by TCD sonography during 10 cycles of 20 s eyes open observing complex moving visual images, and 20 s eyes closed at the end of every cycle. TCD sonography was performed at least at the first 2 days of exacerbation. Mean cerebral BFv throughout the procedure (p=0.003, p=0.001; right and left sides, respectively), velocity at rest (p=0.001, p<0.001), and velocity at stimulation (p=0.021, p=0.01) on both PCAs were significantly lower in patients than controls. However, BFv changes to visual stimulation on both sides were significantly higher in patients (p=0.01, p=0.031) compared to controls. There were negative correlations between P100 latencies and relative blood flow changes on both sides, but it was not significant on the left side. These results may suggest that patients with MS during exacerbation have more reactive vessels in the posterior circulation and! or more reactive neurons in the occipital cortex.

Adult↗
PubMed2002

Sternal cyanoacrylate gluing in mediastinitis. Effects on infection, stability and bone healing.

BACKGROUND: It is crucial to determine stability, histocompatibility and antibacterial properties of the cyanoacrylate used for sternal fixation. METHODS: Clinical study: in 17 cases of mediastinitis, debridement and rewiring the sternum, was applied as the treatment method (Group I). Eighteen cases of mediastinitis were treated with the same method added sternal cyanoacrylate gluing (Group II). A comparative study was done; the follow-up period was 36.7+/-4 and 18.5+/-6.9 months in Group I and II, respectively. Animal study: in 10 rats, upper sternotomy was done and the sternal bone was contaminated. Direct wound closure was done in 4 rats (Group A), in 6 animals, wounds were closed after applying cyanoacrylate in sternal split (Group B). In this prospective study, all rats alive were sacrificed at the 3rd and 8th weeks and sternums were examined histologically. RESULTS: Clinical study: in Group I, 6 patients required additional interventions due to recurrent sternal detachment and osteomyelitis (35.3%). In Group II neither osteomyelitis nor sternal detachment occurred, 3 patients required re-intervention related to cyanoacrylate histotoxicity. Hospital stay was higher in Group I than Group II (24.06+/-4.7 vs 14.16+/-3.98 days, respectively). Experimental study: all of the animals in Group A died of sepsis. In Group B all rats survived the procedure. At the 3rd week histologic evaluations showed that cyanoacrylate was not degraded, and no infection or foreign body reaction was observed. At the 8th week histologic examination showed that cyanoacrylate was completely degraded and replaced by connective tissue. CONCLUSIONS: Cyanoacrylate is effective in diminishing sternal wound complications and related cost and hospital stay of mediastinitis.

Aged↗
PubMed2001

Increased levels of tissue factor pathway inhibitor may reflect disease activity and play a role in thrombotic tendency in Behçet's disease.

Tissue factor pathway inhibitor (TFPI) is a Kunitz-type proteinase inhibitor that has a crucial role in haemostasis and is primarily synthesized in the vascular endothelium. We investigated plasma total TFPI, antiphospholipid antibodies, and some other coagulation and fibrinolytic system parameters in 30 patients with Behçet's disease and 15 controls by the enzyme-linked immunosorbent assay method. TFPI levels were significantly higher in the Behçet's group (119 +/- 57.5 ng/ml) compared with the control group (74.8 +/- 31.5) (P < 0.009). We also noted a statistical significance in TFPI levels between patients with active disease (n:16) (139 +/- 55) and patients without activation (n:14) (96 +/- 53) (P < 0.03), whereas inactive patients lacked any significance when compared with the control group (P < 0.29). Other parameters disclosed no statistical significance between patients and control group except for elevated fibrinogen and plasminogen activator inhibitor-1 levels in the patient group (P < 0.003). Increased levels of TFPI may reflect a defensive mechanism like in other diseases characterized by thrombotic tendency and represent a parameter of disease activity.

Adult↗
PubMed2001

An experimental study evaluating the effect of Mitomycin C on the prevention of postoperative intraabdominal adhesions.

BACKGROUND: Fibroblast proliferation is one of the well-known mechanisms for postoperative intraabdominal adhesion formation. Inhibition of fibroblast proliferation is an attractive field of investigation in the prevention of adhesions. Mitomycin C (MMC) is a cytotoxic agent that alkylates and crosslinks DNA and also inhibits fibroblast proliferation up to a few weeks. We aimed to determine the effect of MMC on the prevention of adhesions. MATERIALS AND METHODS: Generation of adhesions in rats by brushing a 1-cm(2) area of the cecum and the peritoneum on the right side of the abdominal wall was followed by intraperitoneal administration of saline, 1 mg/kg MMC, and 0.5 mg/kg MMC in saline. After 45 days, formation of adhesions was graded. RESULTS: The average adhesion scores of the control, and MMC (1 mg/kg), MMC (0.5 mg/kg) groups were 3.2 +/- 0.7, 0.8 +/- 0.6, and 0.7 +/- 0.8, respectively. Adhesion scores of the two MMC-treated groups were significantly lower than that of the control group (P < 0.001). There was no difference between the two MMC groups (P > 0.05). No side effect of MMC was observed. CONCLUSION: MMC was found to be very effective in the prevention of postoperative intraabdominal adhesions.

Animals↗
PubMed2001

Vitreoretinal surgery for a subretinal hydatid cyst.

PURPOSE: To report the vitreoretinal surgery for management of a subretinal hydatid cyst. METHODS: Conventional pars plana vitrectomy was performed for the removal of a subretinal hydatid cyst and treatment of retinal detachment in the right eye (RE) of a 34-year-old woman. The cyst content was aspirated by a flute needle after retinotomy and cystotomy. The cyst wall was separated from overlying retina and removed. The retina was attached by liquid perfluorocarbon and silicone oil. Postoperatively, the patient was followed for 15 months. RESULTS: After vitreoretinal surgery, the retina RE was attached and recurrence of hydatid disease was not seen in vitreous cavity or subretinal space during the follow-up period. Visual acuity increased from counting fingers to 20/63 at the end of the follow-up time. CONCLUSION: A subretinal hydatid cyst that causes retinal detachment may be treated effectively with vitreoretinal surgery.

Adult↗
PubMed2001

Silicone oil in the surgical treatment of endophthalmitis associated with retinal detachment.

PURPOSE: To investigate the use of silicone oil in the patients who had undergone vitrectomy for the treatment of endophthalmitis associated with retinal detachment. METHODS: Six consecutive cases of endophthalmitis associated with retinal detachment were included in the study. The mean age of the 4 males and 2 females was 47.25 +/- 23.76 years. Endophthalmitis associated with retinal detachment occurred following perforating injuries in 4 eyes, pneumatic retinopexy in I eye and cataract surgery complicated with vitreous loss in I eye. Preoperative visual acuity was light perception-only in all eyes. Red reflex was absent in all eyes. All the patients underwent vitreous tapping, encirclement, vitrectomy, liquid-gas exchange, endolaser photocoagulation and silicone oil injection. RESULTS: Mean follow-up time was 14.3 +/- 7.20 months. The microorganisms that were isolated from the vitreous aspiration were Staphylococcus epidermidis in 3 cases, Staphylococcus aureus in 1 case. Remaining cases were culture negative. Retinal breaks could be found in 4 eyes. Inflammation subsided significantly at 5 days in all cases. Final retinal reattachment and treatment of endophthalmitis was achieved in 5 eyes at the end of follow-up. Final visual acuity was 20/40 in I case, counting finger in 4 cases and no light perception in 1 case. The postoperative complications were optic atrophy in 1 eye, epiretinal membrane in 2 eyes and phitisis bulbi in 1 eye. CONCLUSION: Silicone oil, a retinal tamponading agent that has antimicrobial activity, may have benefical effect in the surgical treatment of endophthalmitis associated with retinal detachment.

Adult↗
PubMed2001

Responses to heat stress in commercial and local broiler stocks. 1. Performance traits.

1. This study investigated effects of conditioning at 5 d of age and food restriction during a hot period on responses to prolonged heat stress of two fast (G1 and G2) and one slower-growing (G3) broiler stocks. 2. Chicks from each stock were divided into 3 groups: control, conditioned (chicks exposed to 36 degrees C for 24 h at 5 d of age) and food restricted (during the heat stress food was withdrawn 2 h before the hot period and chicks were fed between 17.00 and 08.00 h). Prolonged heat stress was induced daily from 28 to 49 d by heating until the ambient temperature reached 32 degrees to 35 degrees C between 10.00 and 17.00 h. 3. Body weights, mortality and rectal temperatures were lower and food conversion higher for stock G3 than G1 or G2. 4. Management procedures used in this study improved food conversion and lowered mortality without affecting body weight. Rectal temperatures of the treated groups were similar to those of the controls.

Adaptation, Physiological↗
PubMed2001

Responses to heat stress in commercial and local broiler stocks. 2. Developmental stability of bilateral traits.

1. Developmental stability of bilaterally symmetrical traits was measured in two fast (G1 and G2) and one slower growing (G3) broiler stocks when conditioned (chicks exposed to 36 degrees C for 24 h at 5 d of age) or food restricted (food withdrawn 2 h before the hot period and chicks fed between 17.00 and 08.00 h) during heat stress administered daily from 28 to 49 d of age. 2. Length of face, length, width and weight of shanks, weights of P. major and P. minor muscles, and weights of lung and caeca were chosen as bilateral traits representative of skeletal, muscle, respiratory and digestive systems. 3. Development of skeletal bilateral traits was affected primarily by genotype and sex. The heart:lung ratio decreased with conditioning in stocks G1 and G2 at 21 d. Face length, shank length and shank weight exhibited antisymmetry, whereas shank width and weights of P. minor, lung and caeca exhibited fluctuating asymmetry and antisymmetry. For P. major weight, there was directional asymmetry. 4. In general, relative asymmetry of skeletal traits was lower than for traits associated with muscle and with respiratory and digestive systems. Relative asymmetry of P. major weight was lower in conditioned and G3 broilers than in their respective counterparts. 5. If relative asymmetry is a valid indicator, item heat stress may be less in slower growing and conditioned broilers.

Adaptation, Physiological↗
PubMed2001

Effects of strain, maternal age and sex on morphological characteristics and composition of tibial bone in broilers.

1. This study was to determine the effects of strain, age of the maternal flock and sex on morphological characteristics and composition of tibial bone of broilers from hatch to 48 d of age. 2. A total of 600 chicks was obtained from 2 strains of broiler breeder flocks (150/chicks/strain/maternal age). Maternal flock age was classified as young (32 to 35 weeks of age) or old (56 to 58 weeks of age). Birds were reared under standard feeding and lighting regimes. 3. On day 1, 16, 32 and 48, twelve birds were selected at random from each maternal group, strain and sex and killed. The wet bone weight and volume were measured. Morphological characteristics of tibia were determined using radiography. Bone breaking strength was tested. Tibia dry matter, ash content, mineral density and collagen level were determined. 4. A quadratic increase occurred with increase in age of broilers for all variables, except proximal width, medial cortex thickness and distal condyle width which increased in a linear manner. 5. Maternal age had a significant effect only on the variably measured at the time of hatch. On day of hatch bone weight, ash content and bone volume were affected by maternal age, but the extent of this also depended on the strain. 6. The differences observed between strains for bone anatomy and bone mineralisation during the rapid growth period of 16 d were not significant at later ages, with the exception of bone volume. Differences between sexes were evident from 16 to 49 d of age with females having lower values.

Aging↗
PubMed2001

Micro embolic signals in patients with cerebral ischaemic events.

The aim of this study was to evaluate the occurrence of micro embolic signals (MES) in patients with a cerebral ischaemia using transcranial doppler monitoring and to find out its diagnostic relevance. We prospectively performed bilateral multigated transcranial doppler monitoring from both middle cerebral arteries in 359 patients with an acute or recent (<4 weeks) cerebral ischaemic event, and in 182 control subjects without a cerebral ischaemic event. MES were analysed according to the standardised protocol. Patients with cerebral ischaemic events had a significantly higher (p<0.00001) rate of MES occurrence (31.8%) than control subjects (5.5%). MES were detected significantly higher in patients with partial or total anterior circulation infarcts (39.1%) than in those with lacunar infarcts (26.0%) or transient ischaemic attacks (27.3%). A correlation of MES and neuroimaging finding was also tried. TCD was found to have a predictive role in microemboli monitoring, predominantly in patients with large vessel territory infarction.

Brain Ischemia↗
PubMed2001

[Clinical approach to trauma-related internal iliac artery pseudoaneurysms (two connected cases)].

Penetrating injuries to abdomen and especially deep gluteal injuries causes vascular and non vascular injuries which necessitates emergency surgery. Surgical management of the penetrating injuries is very difficult, especially exploration of the gluteal region is very difficult. Management of the injury of iliac artery branches is extremely difficult. Two cases with penetrating injury to the gluteal region in 1998 and 2000 one was operated on urgently and the other was operated on electively. Coil embolization was tried to be performed for elective case but intervention was unsuccessful. In both cases internal iliac artery was ligated and aneurysm was repaired. There were no complications in postoperative period. In postoperative angiographic controls, aneurysm in the internal iliac artery was regressed and there were no vascular complications at this region such as hematoma. Penetrating injuries at gluteal region causes injury to the internal iliac artery branches which seriously necessitates emergency management, internal iliac artery ligation and repair.

Adult↗