Biomedical subjects

Hayati Bilgic

Publications and source records attributed to Hayati Bilgic.

13 recordsLinked to original sources

PubMed2006

Serum total cholesterol, HDL-C and LDL-C concentrations significantly correlate with the radiological extent of disease and the degree of smear positivity in patients with pulmonary tuberculosis.

BACKGROUND: Low serum total cholesterol (TC) concentrations in patients with pulmonary tuberculosis (PTB) have been demonstrated. It was shown that a cholesterol-rich diet might accelerate the sterilization rate of sputum cultures in PTB patients. It is known that smear positivity might be related to the radiological extent of disease (RED) in PTB patients. OBJECTIVE: We hypothesized that there might be a relationship between initial serum TC concentrations; the degree of RED (DRED) and the degree of smear positivity (DSP) in PTB patients. METHOD: Eighty-three PTB patients and 39 healthy controls were included in the study. Serum TC, TG, HDL-C, VLDL-C and LDL-C concentrations were determined in all subjects. PTB patients were classified for their chest X-ray findings as minimal/mild, moderate and advanced. Correlations between serum lipid concentrations, DRED and DSP (0, 1+, 2+, 3+, 4+) were investigated. PTB patients and controls were also compared for serum lipid concentrations. RESULTS: Significant differences between PTB patients and controls were detected for serum TC, HDL-C and LDL-C concentrations. On stepwise logistic regression analysis, DRED was found as one of the significant independent predictors of serum TC levels. We also found significant correlations between DRED and serum HDL-C concentrations (r=-0.60, p=0.0001) and between DRED and serum LDL-C concentrations (r=-0.28, p=0.011). There were also significant correlations between DSP and serum lipid concentrations. CONCLUSION: Our study suggests that serum TC, HDL-C and LDL-C concentrations are generally lower in patients with PTB than those in healthy controls. In addition, changes in these parameters might be related to DRED and DSP in PTB patients.

Adult↗

PubMed2006

Serum HDL-C levels, log (TG/HDL-C) values and serum total cholesterol/HDL-C ratios significantly correlate with radiological extent of disease in patients with community-acquired pneumonia.

BACKGROUND: In several studies, it was shown that there was a marked decrease in serum levels of HDL-C during infection and inflammation in general. In particular, a decrease in the level of serum HDL-C was also shown in pneumonia. Correlations between inflammatory markers such as acute phase proteins, cytokines and serum HDL-C levels were shown. However, there are no studies indicating a correlation between serum HDL-C levels and the radiological extent of the disease (RED) in community-acquired pneumonia (CAP). AIM: We hypothesized that there could be a relationship between serum HDL-C levels and RED in CAP. MATERIALS AND METHODS: A case-controlled study, including 97 patients with CAP and 45 healthy subjects, was performed. Chest X-rays of CAP patients were scored for RED, and correlations were investigated between RED scores, serum lipid parameters, the erythrocyte sedimentation rate (ESR) and serum albumin levels. RESULTS: The mean serum HDL-C level was lower in CAP patients than in controls. A significant and negative correlation between RED scores (REDS) and serum HDL-C levels was detected (r = -0.64, P = 0.0001). There were also significant correlations between REDS and other lipid parameters. Significant correlations between ESR and serum HDL-C levels and between ESR and other serum lipid parameters were also found. CONCLUSION: It appears that serum HDL-C levels are generally lower in CAP cases than in healthy controls. Serum HDL-C levels and serum albumin levels might decrease and serum total cholesterol/HDL-C ratios and log (TG/HDL-C) values might increase proportionally with RED in CAP patients. These results might have some significance for individuals having long-standing and/or recurrent pneumonia and other cardiovascular risk factors.

Adolescent↗

PubMed2005

Effects of hyperbaric oxygen treatment on liver functions, oxidative status and histology in septic rats.

OBJECTIVE: The liver is thought to be responsible for multiple organ failure during sepsis. Increase in tissue oxygen consumption is a major component of the septic response. Hyperbaric oxygen (HBO) therapy provides more oxygenation in the whole body. This study examined the effect of HBO alone or in combination with cefepime (CEF) on the liver in septic rats. DESIGN AND INTERVENTIONS: We divided 90 male rats into six groups; control, HBO, sepsis (SEP), SEP+HBO, SEP+CEF, and SEP+CEF+HBO. Sepsis was induced with an intraperitoneal injection of Escherichia coli (2.1 x 10(9) cfu). A total of six HBO sessions were performed at 2 atm absolute for 90 min at 6-h intervals. CEF was administered intraperitoneally at a dose of 50 mg/kg twice daily. Animals were killed 48 h after sepsis induction. Their liver and blood were removed for biochemical and histopathological analysis. MEASUREMENTS AND RESULTS: Liver thiobarbituric acid reactive substances as well as serum alanine transaminase, aspartate transaminase and alkaline phosphatase levels increased while the activity of the antioxidant enzymes superoxide dismutase and catalase decreased significantly in septic rats. These parameters returned to nearly control levels in the SEP+CEF+HBO group. Histological observations supported these findings: Hepatocellular degeneration was observed and intensive polymorphonuclear cell infiltration appeared in all fields of septic animal livers. HBO alone could not sufficiently reverse these histopathological changes, but most liver sections presented normal histology when it was combined with CEF. CONCLUSIONS: HBO may be a useful adjuvant therapy modality to improve the efficacy of sepsis treatment.

Animals↗

PubMed2005

Pleural fluid and serum procalcitonin as diagnostic tools in tuberculous pleurisy.

BACKGROUND: Diagnosis of tuberculous pleuritis is difficult because of its nonspecific clinical presentation and decreased efficiency of traditional diagnostic methods. We investigated the use of procalcitonin (PCT) concentration in tuberculous pleuritis diagnosis. METHODS: A prospective clinical study was performed with two different patient groups. A total of 28 patients were included: 18 with tuberculosis and 10 with nontuberculous pleurisy. Serum and pleural fluid PCT concentrations were evaluated before treatment. RESULTS: Serum and pleural fluid PCT concentrations were statistically different between tuberculous and nontuberculous pleurisy groups (P = 0.012 and P = 0.004, respectively), even though they were not elevated in relation to the cut-off level of 0.5 ng/mL. A positive and significant correlation was detected between serum and pleural fluid PCT levels (r = 0.49, P = 0.008). Diagnostic specificity and sensitivity values for serum and pleural fluid PCT in discriminating tuberculous from nontuberculous pleurisy were 80% and 72.2%, and 90% and 66.7% at the 0.081 and 0.113 ng/mL cut-off values, respectively. CONCLUSION: Relative to the current cut-off level of 0.5 ng/mL, PCT concentration is not a useful parameter for the diagnosis of tuberculous pleurisy. Because there were PCT levels in patients with tuberculous pleurisy that were below the current cut-off level but were significantly different from those of the nontuberculous group, the use of PCT should be further investigated.

Adolescent↗

PubMed2005

Correlation between hyperbaric oxygen exposure pressures and oxidative parameters in rat lung, brain, and erythrocytes.

OBJECTIVES: The oxygen toxicity risk of hyperbaric oxygen (HBO) treatment has long been of interest. However, there are no comprehensive articles describing the relationship between HBO protocols and oxidative parameters used clinically. The purpose of this study was to determine the effects of various HBO pressure modalities on the oxidative values of rat lung, brain, and erythrocytes. DESIGN AND METHODS: A total of 64 male Sprague-Dawley rats was randomly divided into 7 groups. Group A was used as a control. Groups C to G were subjected to 100% oxygen at a pressure of 1, 1.5, 2, 2.5, and 3 ATA (atmosphere absolute), respectively, for 2 h. Group B was exposed to normal atmospheric air at 3 ATA for the same duration. The rat's lung, brain, and blood were taken immediately after the exposure and thiobarbituric acid reactive substances (TBARS) and superoxide dismutase (SOD) levels were determined. RESULTS: Both TBARS levels and SOD activity increased concordantly with the pressure increase. Although a statistically significant change in TBARS levels started from 100% oxygen exposure at 1 ATA (normobaric), SOD activity was affected after 2 ATA. A significant correlation exists between exposure pressure and the aforementioned parameters. Ambient air exposure at 3 ATA did not affect any parameters besides the brain TBARS levels. CONCLUSIONS: It is clear that HBO exposure causes oxidative stress. The main reason for this effect seems to be exposure to pure oxygen, since pure high pressure has no significant effect on the aforementioned parameters. However, clinicians should use as low pressures as possible since all oxidative parameters appear to be directly proportional to the extent of HBO exposure.

Animals↗

PubMed2005

High resolution computed tomographic features of pulmonary alveolar microlithiasis.

BACKGROUND: Pulmonary alveolar microlithiasis (PAM) is a rare, chronic lung disease with unknown etiology and with a nonuniform clinical course. Nonuniformity of clinical course might be related to the degree of pulmonary parenchymal alterations, which can be revealed with high resolution computed tomography (HRCT). However, HRCT findings of PAM were not fully described in the current literature. AIM: The aim of this study was to interpret and to contribute to describe HRCT findings of PAM and to investigate a correlation between profusion of micro nodules (MN) and pulmonary parenchymal alterations in patients with PAM. MATERIAL AND METHODS: Ten male patients with PAM (mean age: 22+/-3.2) were included into the study. HRCT images were assessed for patterns, distribution, and profusion of pulmonary abnormalities. Dividing the lungs into three zones, profusion of abnormalities was assessed. A profusion score (1-4) was given and the scores of each zone were then summed to obtain a global profusion score for HRCT ranging from 0 to 12. Also a parenchymal alteration score (PAS) was defined with respect to profusion of abnormalities. Chest X-rays were also scored. RESULTS: All of ten patients with PAM had findings of interstitial lung disease in varying degrees on their HRCTs. HRCT findings of patients with PAM were as following: MN, parenchymal bands (PB), ground glass opacity (GGO) and, sub pleural interstitial thickening (SPIT) in 10 patients; interlobular septal thickening (ILST), in 9 patients; paraseptal emphysema (PSA) in 8 patients; centrilobular emphysema (CLA) in 7 patients; bronchiectasis (BE), confluent micro nodules (CMN) in 6 patients; peri bronchovascular interstitial thickening (PBIT) in 5 patients; panacinar emphysema (PANAA) in 3 patients; pleural calcification (PC) in 2 patients. A significant correlation between MN scores and PAS (r=0.68, p=0.031, MN scores and GGO scores (r=0.69, p=0.027) and, MN scores and CLA scores (r=0.67, p=0.034) was detected. We also found significant correlations between HRCT scores and results of pulmonary function tests (PFTs), HRCT scores and chest X-ray score (CXRS) and, CXRS and results of PFTs. CONCLUSION: We conclude that patients with PAM may have all findings of interstitial lung disease in varying degrees as well as MNs on their HRCTs. More importantly, this study suggests a proportional relationship between profusion of MNs and parenchymal alterations in patients with PAM. This study also suggests that the degree of parenchymal alterations closely related with the degree of pulmonary function loss in patients with PAM.

Adult↗

PubMed2005

Peroxynitrite may be involved in bladder damage caused by cyclophosphamide in rats.

PURPOSE: It was previously shown that nitric oxide (NO) produced by inducible NO synthase (iNOS) is responsible for cyclophosphamide (CP) induced cystitis. In this study we evaluated whether peroxynitrite is also responsible for CP induced bladder damage in rats. MATERIALS AND METHODS: A total of 38 male albino Wistar rats were divided into 4 groups. Group 1 served as controls and was given 2 ml saline, while 3 groups received a single dose of CP (200 mg/kg) at the same intervals. Group 2 received CP only, group 3 received the selective iNOS inhibitor aminoguanidine (AG) (100 mg/kg) and group 4 received the peroxynitrite scavenger ebselen (2-phenyl-1,2-benzisoselenazol-3[2H]-one) (20 mg/kg). RESULTS: CP injection resulted in severe cystitis with continuous macroscopic hemorrhage, strong edema, inflammation and ulceration. Moreover, bladder tissue malondialdehyde levels, iNOS activation and urine nitrite-nitrate levels were dramatically increased. AG histologically protected bladder against CP damage and decreased urine nitrite-nitrate levels, bladder malondialdehyde and iNOS induction. Ebselen showed results similar to those of AG without changing the urinary nitrite-nitrate level and iNOS activity. CONCLUSIONS: These results suggest that not only nitric oxide, but also peroxynitrite may be important in the pathogenesis of CP induced cystitis.

Animals↗

PubMed2005

Melatonin ameliorates bladder damage induced by cyclophosphamide in rats.

Cyclophosphamide (CP), an alkylating antineoplastic agent, has potential urotoxicity including causing hemorrhagic cystitis (HC). HC is now accepted as a non-infectious inflammation and the pathogenesis of HC includes cytokine production which leads to inducible nitric oxide synthase (iNOS) induction. Moreover, overproduction of reactive oxygen species (ROS) during inflammation leads to extensive oxidative stress, cellular injury and apoptosis/necrosis via several mechanisms. Based on these facts, the aim of this study was to evaluate the protective effects of melatonin as an antioxidant, iNOS inhibitor and peroxynitrite scavenger against CP-induced urinary bladder damage. A total of 30 male Sprague-Dawley rats were divided into four groups. Three groups received a single dose of CP (100 mg/kg) intraperitoneally with the same times. Group 2 received CP only, group 3 received 5 mg/kg/day and group 4 received 10 mg/kg/day melatonin before and the day after CP administration. Group 1 served as the control. Increased iNOS induction, bladder malonyldialdehyde (MDA) levels and urinary nitrite-nitrate excretion were encountered in the CP-only group leading to severe cystitis. Melatonin exhibited significant protection against CP-induced cystitis by diminishing bladder oxidative stress and blocking iNOS and peroxynitrite production. Oxidants may have a major role in the pathogenesis of CP-induced cystitis and iNOS is an important mediator leading to peroxynitrite production. Melatonin ameliorates bladder damage induced by CP.

Animals↗

PubMed2004

Exogenously administered and endogenously produced melatonin reduce hyperbaric oxygen-induced oxidative stress in rat lung.

Hyperbaric oxygen (HBO) is a widely used treatment modality in many diseases. A known side effect of HBO is the production of reactive oxygen species. Many antioxidants such as vitamins C and E, riboflavin and selenium have been used successfully to scavenge the reactive oxygen species caused by HBO administration. In this study, we aimed to see if melatonin, a newly discovered antioxidant, has a protective effect against the overproduction of reactive oxygen species produced by HBO in rat lung tissue. Sixty male Sprague-Dawley rats were divided into 5 groups as follows: control, daytime HBO (3 ATA, 120 min), daytime HBO plus melatonin (10 mg/kg), nighttime HBO and nighttime HBO (under light exposure). The MDA, SOD and CAT levels of daytime and nighttime HBO (under light exposure) increased significantly. This significance was not found in the daytime HBO plus melatonin and nighttime HBO groups when compared with the control. In this study, HBO caused oxidant stress, and melatonin decreased the levels of MDA, SOD and CAT. Moreover, endogenous melatonin was found to be a more effective antioxidant than exogenous 10 mg/kg melatonin.

Animals↗

PubMed2004

Inducible nitric oxide synthase inhibition in cyclophosphamide induced hemorrhagic cystitis in rats.

Cyclophosphamide (CP) is an antineoplastic agent used alone or in combination with other chemotherapeutic agents for the treatment of many neoplastic diseases. Hemorrhagic cystitis (HC) is a major potential toxicity and dose limiting side effect of CP. Recently, it has been shown that endogenous inflammatory mediators are involved in cystitis by increasing nitric oxide (NO) production in target tissue. The aim of this study was to evaluate the relationship between NO and CP induced hemorrhagic cystitis HC in rats. A total of 30 female Spraque-Dawley rats were divided into 4 groups. Group 1 served as control, three groups received single dose of CP (100 mg/kg) intraperitoneally (i.p.): group 2 received CP only. Group 3 received the NO precursor L-arginine (80 mg/kg/day), and group 4 received the selective inducible NO synthase (iNOS) inhibitor S-methylisothiourea (SMT; 20 mg/kg/day) before and the day after cyclophosphamide injection. CP injection resulted in severe cystitis. SMT but not L-arginine produced marked inhibition of CP induced bladder damage. We concluded that NO produced by iNOS, is an important mediator in the pathogenesis of CP induced cystitis.

Animals↗

PubMed2003

Involvement of nitric oxide and hyperbaric oxygen in the pathogenesis of cyclophosphamide induced hemorrhagic cystitis in rats.

PURPOSE: We evaluated the relationship between nitric oxide and hyperbaric oxygenation in the pathogenesis and treatment of cyclophosphamide induced hemorrhagic cystitis in rats. MATERIALS AND METHODS: Cyclophosphamide (100 mg/kg) was injected in male Sprague-Dawley rats for cystitis induction. Animals were treated before and the day after cyclophosphamide injection with 100 mg/kg of the nitric oxide substrate L-arginine, 20 mg/kg of the nonselective nitric oxide synthase inhibitor L-NG-nitroarginine methyl ester and 20 mg/kg of the selective inducible nitric oxide synthase inhibitor S-methylisothiourea. Animals were exposed to hyperbaric oxygen (2.8 atmospheres absolute for 90 minutes twice daily) with or without the administration of L-arginine and nitric oxide synthase inhibitors. RESULTS: Cyclophosphamide injection resulted in severe cystitis. S-methylisothiourea produced marked inhibition of cyclophosphamide induced bladder tissue damage. L-arginine and L-NG-nitroarginine methyl ester failed to a show meaningful protective effect. Hyperbaric oxygen protected the bladder only against ulceration. Moreover, hyperbaric oxygen did not contribute to the protective effects of L-arginine, L-NG-nitroarginine methyl ester or S-methylisothiourea. CONCLUSIONS: Nitric oxide produced by inducible nitric oxide synthase is an important mediator in the pathogenesis of cyclophosphamide induced cystitis. Hyperbaric oxygen has a beneficial effect on repairing bladder damage rather than on bladder protection.

Animals↗

PubMed2002

Investigation of the correlation between inappropriate hospitalization and hospital stay rate: an application in medical clinics of a military hospital.

BACKGROUND: Medical services play a major role in hospital facilities. Along with the medical applications and diagnoses, physicians affect the hospital costs by 70% to 80%. Therefore, the hospital administrators should establish some systems that can modify the current application models of physicians. OBJECTIVE: This study aimed to investigate the appropriateness of hospitalization days and length of stay of the patients in 13 internal clinics in a military hospital. STUDY DESIGN: 5,205 patient days belonging to 416 patients were evaluated by Appropriateness Evaluation Protocol. Patients' data were retrospectively collected by using a "data collection form" through patients' files and then were evaluated by frequencies and percentage distributions. RESULTS: The unnecessary hospitalization rate and unnecessary stay rate were 4.8% and 15.75%, respectively. The highest unnecessary hospitalization rates were in nuclear medicine (50%). CONCLUSION: It was concluded that the inappropriate hospitalization rate and inappropriate stay rates were 4.8% and 15.75%, respectively.

Decision Making↗

PubMedDate not supplied

The roles of HRCT and clinical parameters in assessing activity of suspected smear negative pulmonary tuberculosis.

BACKGROUND: Smear-negative pulmonary tuberculosis (SNPTB) constitutes a major problem in countries with a moderate or high TB prevalence. The value of high-resolution computed tomography (HRCT), chest x-ray and other clinical findings in determining activity of SNPTB were investigated. METHODS: The study population consisted of 85 patients with suspected SNPTB, of whom 52 were confirmed as active pulmonary TB according to either culture positivity for Mycobacteriun tuberculosis or demonstration of caseous granulomatous inflammation. The remaining 33 patients accepted inactive TB sequel. RESULTS: Cough and expectoration were significantly frequent in inactive group whereas chest pain was detected higher in active patients. Sensitivity, specificity, positive predictive value, negative predictive value and diagnostic accuracy of HRCT in detecting disease activity were 88, 88, 92, 83 and 88%, respectively. Centrilobular nodules, other non-calcified nodules, consolidation and cavity were significantly higher on HRCT in active group. Chest x-ray scores that were graded 1 to 3 showed a linear trend for the disease activity. CONCLUSIONS: HRCT has good diagnostic value in detecting activity of SNPTB, and some clinical findings may help in predicting the activity.

Adult↗