Calculated Globulin Is Clinically Useful as a Screening Test for Antibody Deficiency in Turkish Adult Patients.

INTRODUCTION: Heterogeneous clinical features of antibody deficiency (AD) may cause diagnostic delays. Calculated globulin (CG) (total protein minus albumin) has been proposed as a screening test to prevent morbidity due to diagnostic delays in AD. Our aim was to validate CG as a screening test for AD in Turkish adult patients by comparing its role with gamma globulin analysis in protein electrophoresis. METHODS: Fifty serum samples were randomly collected for each level of CG from 15 to 25 g/L and tested for serum IgG, IgA, IgM levels and protein electrophoresis. Cut-off values predicting low IgG levels were calculated for electrophoretically determined gamma globulin and CG. Additionally, the data of 47 patients followed up in our clinic with a diagnosis of primary antibody deficiency (PAD) were retrospectively analyzed. RESULTS: A total of 550 adult patients were included in the study. The CG value predicting patients with IgG <6 g/L as a screening test was determined as <20 g/L with 83.8% sensitivity and 74.9% specificity. The gamma globulin value which predicted patients with the same IgG value of 89.0% sensitivity and 89.4% specificity was determined as <7 g/L. In the retrospective analysis, 37 of 47 patients (78.7%) with PAD had a CG value of <20 g/L at the time of the diagnosis and all 13 patients (100%) whose gamma globulin values were measured at the time of the diagnosis had a gamma globulin value of <7 g/L. CONCLUSION: The determined CG cut-off value of <20 g/L can be used as a screening test in Turkish adult patients.

Galectin-3 as a Novel Biomarker for Predicting Clinical Outcomes in Hospitalized COVID-19 Patients.

BACKGROUND: Galectin-3 has been shown to play a key pathophysiological role in pulmonary associated inflammatory response and lung fibrosis in COVID-19 and is a mediator for viral adhesion. However, there is limited data about its potential role in severity and prognosis of COVID-19. This study aimed to investigate the predictive role of serum galectin-3 concentrations in the severe clinical outcomes of hospitalized COVID-19 patients: the severity of pneumonia, in-hospital mortality, and the need for intensive care unit (ICU) admission. METHODS: This single-center study included 68 patients with laboratory- and radiologically-confirmed COVID-19 admitted to our emergency department. The study population was divided into patients with primary clinical out-comes (n = 32) and those without (n = 36). The need for ICU admission and/or in-hospital mortality were the primary clinical endpoints. The study group was also classified based on pneumonia severity: severe or mild/moderate. Blood samples were collected within 48 hours of admission to estimate serum galectin-3 concentrations. RESULTS: Multivariate regression analysis showed that lower concentrations of galectin-3 and arterial oxygen saturation (SpO2) were independently associated with the primary clinical outcomes (OR = 0.951, p = 0.035; OR = 0.862, p = 0.017, respectively); increased concentrations of galectin-3 were an independent predictor of severe pneumonia (OR = 1.087, p = 0.016). In the receiver operating characteristics curve analysis, serum galectin-3 concentrations at hospital admission predicted pneumonia severity with 52.1% sensitivity and 90% specificity with a cutoff of 38.76 ng/mL. CONCLUSIONS: Circulating galectin-3 at hospital admission could be a useful biomarker for identifying COVID-19 patients at high risk for severe pneumonia.

Would Tracking Coagulation Together with Inflamation Markers be a Prospect for COVID-19 Disease Prognosis?

BACKGROUND: The purpose of this study is to evaluate the prognostic roles of hemostatic tests including prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, D-dimer, and antithrombin III in the progression of disease, monitorization of severe, mild and moderate cases, and also to show their relationship with inflammatory markers including C-reactive protein (CRP), procalcitonin, and interleukin-6 (IL-6). METHODS: The study comprised 604 patients (360 men and 244 women) with confirmed SARS-CoV-2 infection admitted to Emergency Department of Istanbul Faculty of Medicine between March 15 and April 15, 2020. The variations in the concentration of coagulation tests and inflammatory markers were observed from the admission to hospital to the 10th day with three-day periods. RESULTS: PT level and PT activity of severe cases were significantly different compared to mild cases (p = 0.012, p = 0.010, respectively). Similarly, aPTT and D-dimer levels in severe cases were significantly higher compared to the mild cases. However, fibrinogen levels of mild cases were significantly lower compared to either moderate or severe cases (p < 0.001, for both). The PT, PT activity, aPTT, and D-Dimer levels in severe cases were significantly different compared with the mild cases. However, fibrinogen level was the highest in severe cases, and higher than either mild or moderate cases. CONCLUSIONS: Our findings reveal the vital importance of measuring coagulation parameters at the time of admission and monitoring them at regular intervals in clinical monitoring of COVID-19 patients, in determining the severity of the disease in terms of the patient's prognosis, and in choosing and applying the appropriate treatment at the right time.

IgG-RBD Response Due to Inactivated SARS-CoV-2 Vaccine: Alteration in D-Dimer and Fibrinogen Concentrations, Association with Comorbidities and Adverse Effects.

OBJECTIVE: To examine the immunoglobulin G-receptor-binding domain (IgG-RBD) response and changes in fibrinogen and D-dimer concentrations in individuals with a past coronavirus infection and followed by CoronaVac. METHODS: The study consisted of a total of 116 participants. Blood samples were drawn from subjects 21-25 days after they received first and second doses of CoronaVac as well as from individuals with a past infection. Fibrinogen, D-dimer, and IgG-RBD concentrations were measured. RESULTS: The IgG concentrations of the vaccinated subjects were significantly higher (P < .001), fibrinogen levels were lower (P < .001), and D-dimer levels increased following the second vaccination compared with the first vaccination (P = .083). No difference was obtained in IgG-RBD between vaccinated and previously infected individuals (P = .063). The differences in fibrinogen and D-dimer were statistically nonsignificant between both groups. CONCLUSION: The CoronaVac vaccine appears to be safe and effective. It is essential for individuals to take personal protective measures, such as using masks and distancing.

Performance Evaluation of Sysmex CN-3000 and Stago STA R Max Coagulation Analyzers and Interference of Hemolysis.

BACKGROUND: In this study, our purpose was to evaluate the analytical performances of the STA R Max and CN-3000, and compare the results of both for PT, aPTT, fibrinogen, D-dimer, and factor VIII, and also to show the influence of hemolysis on PT, aPTT, and fibrinogen assays. METHODS: Three hundred ninety-five randomly-selected blood samples from residual material from Istanbul Faculty of Medicine, Central Laboratory workflow comprised the study group. PT, aPTT, fibrinogen, D-dimer, and factor VIII activity were done using both analyzers. Analytical performances were determined through precision, linearity, and comparability studies. Artificial hemolysis was performed through freezing-thawing and mechanical-sheer methods. RESULTS: Intra-assay and between-day CVs% of PT and aPTT were lower than 5% for STA R Max and CN-3000. Only the within-run and between-day CVs% of fibrinogen and the between-day CVs% of D-dimer were higher than 5%, but in acceptable targets. Intra-assay and between-day CVs% of FVIII on the CN-3000 were 3.5% and 12.3% at the low and 2.5% and 5.3% at high level, and 1.8% and 3.7% at the low and 6.3% and 5.9% at high level on the STA R Max. The comparison results of PT, aPTT, fibrinogen, and D-dimer were good (r > 0.91), also good correlations were obtained for FVIII activity > 40 IU/dL and FVIII between 5 - 40 IU/dL (r = 0.89). The results of the hemolysis study were within acceptable limits of the recommended criteria of Fraser and the manufacturer. CONCLUSIONS: CN-3000 and STA R Max coagulation analyzers are accurate and highly precise systems for safe use in clinical diagnostic applications. The interferences obtained for both analyzers were found to be within accepted targets.

Role of green technology innovation and renewable energy in carbon neutrality: A sustainable investigation from Turkey.

After the Paris Climate Conference (COP21), many countries start progressing towards carbon neutrality targets. In doing so, green technology innovations (GTIs) and clean energy are the essential factors that can help to achieve the carbon neutrality goal. Therefore, this paper examines the linkages between green technology innovation and renewable energy and carbon dioxide emissions based on the STIRPAT model in Turkey during the time of 1990-2018. The study used testing like "unit-root" to verify the variables' integrative properties containing the information for structural breaks. Also, the bootstrapping ARDL-bound testing technique is used to analyze the relationship between the variables. The causal relationship between green technology innovation, energy consumption, renewable energy, population, income per capita, and carbon dioxide emissions is tested through a Granger causality test. The empirical findings show that green technology innovation, renewable energy, energy consumption, population, income per capita, and carbon dioxide emissions are co-integrated for the long-term association. Additionally, green technology innovation and renewable energy decline carbon dioxide emissions, whereas energy consumption, population, and per capita enhance carbon emissions. This paper helps the policymakers design a comprehensive policy for strengthening environmental sustainability through green technology innovation and renewable energy, specifically in the region of Turkey.

The understanding of the immunopathology in COVID-19 infection.

Coronaviruses belonging to the Coronaviridae family are single-stranded RNA viruses. The entry of SARS-CoV-2 is accomplished via ACE-2 receptors. SARS-CoV-2 infection coactivates both innate and adaptive immune responses. Although SARS-CoV-2 stimulates antibody production with a typical pattern of IgM/IgG, cellular immunity is also impaired. In severe cases, low CD4 + and CD8 + T cell counts are associated with impaired immune functions, and high neutrophil/lymphocyte ratios accompanying low lymphocyte subsets have been demonstrated. Recently, high IFN -α/γ ratios with impaired T cell responses, and increased IL-1, IL-6, TNF-α, MCP-1, IP-10, IL-4, IL-10 have been reported in COVID-19 infection. Increased proinflammatory cytokines and chemokines in patients with severe COVID-19 may cause the suppression of CD4 + and CD8 + T cells and regulatory T cells, causing excessive inflammatory responses and fatal cytokine storm with tissue and organ damage. Consequently, novel therapeutics to be developed against host immune system, including blockade of cytokines (IL-6, IL-1, IFN) themselves, their receptors or signaling pathways- JAK inhibitors- could be effective as potential therapeutics.

Congenital Factor XIII Deficiency With the Presence of Inhibitor: A Case Study.

Coagulation factor XIII (FXIII) is a fibrin-stabilizing factor with additional roles in wound healing and interactions between the decidua and fetus. Congenital FXIII deficiency is rare bleeding disorder. Inhibitor development against FXIII in inherited FXIII deficency is also uncommon, but may cause severe, life-threatening bleeding. FXIII is the last step in the coagulation cascade with normal coagulation paramaters (PT, aPTT), the detection of inhibitor to FXIII is quite difficult. The treatment of inhibitor-positive congenital FXIII deficiency is challenging due to the lack of a role of by-pass agents such as FVII. The best known ways of treatment in these cases are the use of high-dose FXIII concentrates and immunosuppression. Herein, we report the management of postoperative bleeding diathesis in a patient with FXIII deficiency who developed inhibitors, and to follow the clinical course of the disease with FXIII concentrate and immunosuppression.

Serum Endocan Levels on Admission Are Associated With Worse Clinical Outcomes in COVID-19 Patients: A Pilot Study.

Thrombotic and embolic complications in the cardiovascular system are evident and associated with worse prognosis in coronavirus disease 2019 (COVID-19) patients. Endothelial-specific molecule 1 (endocan) plays a role in vascular pathology. We hypothesized serum endocan levels on admission are associated with primary composite end point (mortality and intensive care unit hospitalization) in COVID-19 patients. Patients (n = 80) with laboratory, clinical, and radiological confirmed COVID-19 were included in this cross-sectional study. Ten milliliter of peripheral venous blood were drawn within 24 hours of admission to estimate serum endocan levels. Data were analyzed using SPSS version 26.0 (IBM). Patients with the primary composite end point had significantly higher serum endocan levels than patients without (852.2 ± 522.7 vs 550.2 ± 440.8 ng/L, respectively; P < .01). In the logistic regression analysis, only increased serum endocan levels and increase in age were independent predictors of the primary composite end point (P < .05). In the receiver operating characteristics curve analysis, we found that a serum endocan level of 276.4 ng/L had a 97% sensitivity and 85% specificity for prediction of the primary composite end point. Baseline serum endocan levels may prove useful as a prognostic factor in patients hospitalized for COVID-19.

Evaluation of Chromogenic Factor VIII Assay Compared with One-Stage Clotting Assay.

BACKGROUND: Congenital factor VIII (FVIII) deficiency causes hemophilia A due to different types of defects in the FVIII gene. Although the chromogenic measurement is the reference method and shows less variability, a one-stage assay is the most commonly preferred method for measurement of FVIII. In this study, we aimed to evaluate the analytical performances of chromogenic and one-stage assays, and compare the results prior to introduction of newly developed extended half-life recombinant FVIII products. METHODS: Sixty-six blood samples from residual material of Istanbul Faculty of Medicine, Central Laboratory workflow comprised the study group. Samples were classified; plasma FVIII > 40 IU and FVIII < 40 IU. FVIII activities were measured using one-stage clotting and chromogenic assays on a CS-2500 analyzer. Analytical performances were determined through precision, linearity, carryover, and comparability studies. RESULTS: The within-run CV% of the one-stage assay on the CS-2500 had 1.6%, 2.6%, the between day CV% were 8.5%, 4.9 % for low and high controls, respectively. The within-run CV% of chromogenic method had 1.2% and 0.9%. Both methods demonstrated good linearity (R2 > 0.998), and the comparisons of both assays exhibited good agreement with minor bias for FVIII activity > 40 IU. However, a significant bias was obtained for FVIII activity < 40 IU. CONCLUSIONS: We obtained higher results using the one-stage assay compared with the chromogenic assay, and a significant bias was found for the samples lower than 40 IU. The discrepancy can explained by the presence of a weak agreement for samples lower than 10 IU due to the lower detection limit of the chromogenic assay used in this study (1.5%).

Performance of automated urine analyzers using flow cytometric and digital image-based technology in routine urinalysis.

The purpose of this study was to evaluate the analytical performances of Sysmex UF-5000 and Dirui FUS-200 and to compare the results with manual microscopy and between each other. Two hundred fifty urine samples were analyzed for evaluation. Mid-stream specimens were studied sequentially using Dirui FUS-200 and Sysmex UF-5000, and also with manual microscopy within one hour. The physical and chemical components of urinalysis, and sediment results were investigated. The precision results of the FUS-200 and UF-5000 for WBCs, RBCs, and ECs were acceptable. The both analyzers demonstrated good linearity (r > 0.97), with no carry-over. The comparisons of FUS-200 and UF-5000 with manual microscopy for RBCs, WBCs, and ECs on 250 samples exhibited good agreement with little bias (R > 0.780). Only, the moderate agreements were obtained for calcium oxalate for both analyzers (R = 0.512, and 0.648, respectively). The sensitivities of the FUS-200 and UF-5000 were 75.8% and 86.8%, with specificities of 92.3% and 87.8% for WBCs, for RBCs the sensitivities were 91.1%, and 84.4% with specificities of 82.2%, and 89.6% for both analyzers. Kappa values of the UF-5000 were higher than FUS-200 for WBCs, RBCs, ECs, and calcium oxalate. The FUS-200 and UF-5000 urine analyzers, are both accurate, very precise systems and can be safely used in clinical laboratories. However, due to the technological characteristics of the UF-5000 analyzer, its positive impacts on the morphologic recognition and enumeration of RBCs and WBCs should be taken into account, particularly in university hospital laboratories with high patient volumes.

The Role of the Local Bone Marrow Renin-Angiotensin System in Multiple Myeloma

Objective: Angiotensin II promotes growth and angiogenesis via type 1 receptors (AGTR1) in certain tumors. In this study, we examine the bone marrow AGTR1 expression in multiple myeloma (MM) and its relationship with the regulation of angiogenesis and prognostic factors. Materials and Methods: Bone marrow AGTR1 mRNA levels of 39 MM patients and 15 healthy controls were analyzed with quantitative RT-PCR. Immunohistochemical staining of the tissue vascular endothelial growth factor (VEGF), CD34, and factor VIIIrAg (fVIIIrAg) was used to assess bone marrow angiogenesis. Results: Bone marrow samples of the patients showed increased VEGF, fVIIIrAg, and CD34 staining and higher AGTR1 expression levels when compared to controls. Patients with severe-diffuse bone marrow infiltration showed higher bone marrow VEGF, fVIIIrAg, CD34, and AGTR1 mRNA levels when compared to other patients. Conclusion: AGTR1 expression was found positively correlated with plasma ß2-microglobulin level and patients with increased AGTR1 expression showed increased bone marrow CD34 levels.

Effects of betaine supplementation on nitric oxide metabolism, atherosclerotic parameters, and fatty liver in guinea pigs fed a high cholesterol plus methionine diet.

OBJECTIVE: The aim of this study was to investigate the effect of high cholesterol (CHOL) and CHOL + methionine (MET) diets on atherogenic and oxidative index parameters and on the factors that influence nitric oxide (NO) bioavailability. Also, attempts were made to determine whether dietary betaine (BET) resulted in any improvement in the changes that occurred after CHOL + MET administration. METHODS: Guinea pigs were fed chow containing 1.5% CHOL with or without 2% MET for 10 wk. A third group received the CHOL + MET + BET diet. Control groups were given standard chow or standard chow + BET. Arginine, NO, nitrotyrosine (NT), and asymmetric dimethylarginine (ADMA) levels; lipid profile; and dimethylarginine dimethylaminohydrolase (DDAH) activity were measured. The liver and aorta were subjected to histopathologic analysis. RESULTS: The CHOL + MET diet caused higher serum CHOL and homocysteine levels, but no further increases were seen in aortic CHOL and diene conjugate (DC) levels and histopathologic lesions as compared with the CHOL group. Hepatic lipids and DC levels were also higher, and histopathologic lesions were more severe. CHOL + MET feeding increased ADMA and NT levels as compared with those of the CHOL-fed group. When BET (1 g/kg body weight/d) was added to the CHOL + MET diet, homocysteine and lipid levels decreased and histopathologic changes were reversed. BET diet decreased serum ADMA and hepatic and aortic DC levels and partly restored DDAH activity. CONCLUSIONS: BET supplementation may be effective in preventing hyperlipidemia, disturbed NO availability, oxidative stress, and the development of fatty liver and atherosclerotic lesions that might result from excess amounts of cholesterol and methionine in the diet.

Mean Platelet Volume in Heterozygous Beta Thalassaemia.

BACKGROUND/AIM: It is not known why cerebrovascular and cardiovascular ischaemic events are less frequently observed in heterozygous beta thalassaemia (HBT) patients than in the general population. However, we previously reported that serum levels of some platelet function markers, i.e. soluble CD40 ligand and soluble P-selectin, are lower in patients with HBT than in controls. A high mean platelet volume (MPV) is an indicator of in vivo platelet activation and may indicate a tendency to thrombosis. We investigated whether MPV is lower in HBT patients than in controls. METHODS: Forty-eight patients with HBT were compared with 51 controls matched for gender, age, and BMI for MPV in a cross-sectional study. RESULTS: The MPV was within the normal range and higher in the HBT group (9.64 ± 1.20 vs. 9.07 ± 082 fL, p = 0.006). The 2 groups were similar in terms of atherosclerosis risk factors and medications. After linear regression analysis, the MPV was correlated with HBT, sensitive CRP, and BMI. CONCLUSION: The higher MPV in patients with HBT could indicate platelet activation, and this may represent a dilemma. Higher MPV in the HBT group might have resulted from higher sympathetic nervous system activity, mild ineffective erythropoiesis, and haemolysis.

Evaluation of High Performance Liquid Chromatography and Liquid Chromatography-Tandem Mass Spectrometry Methods for 25 (OH) D3 Assay.

BACKGROUND: This study was designed to compare the performances of HPLC (High Performance Liquid Chromatography) and LC-MS/MS (Liquid Chromatography-Tandem Mass Spectrometry) methods in 25 (OH) D3 testing. METHODS: This study is comprised of 306 randomly chosen plasma samples from the subjects who applied for routine measurement of 25 (OH) D3. Plasma 25 (OH) D3 levels were quantified using HPLC and LC-MS/MS. The LC-MS/MS method was used as the reference method. The linearity, precision, carry-over, limit of blank, limit of detection (LoD), and comparison studies were done for method validation. Accuracy was tested using external quality assurance samples. RESULTS: Coefficients of variation for both methods were at around 10.0%. The HPLC and LC-MS/MS assays were linear over the working range from 5.0 to 100 ng/mL (r > 0.99). The HPLC assay showed a higher LoD compared to LC-MS/MS (5.1 vs. 1.6 ng/mL, respectively). Results from external quality assurance samples were within ? 1 SD range for both methods. The comparison study revealed good correlation between HPLC and LC-MS/MS methods (y = 1.054x - 1.981 with a small mean bias (-0.953) (r = 0.9752)), when all samples were included, regardless of their 25 (OH) D3 levels. However, the correlation was poor for samples with 25 (OH) D3 concentrations lower than 10 ng/mL. CONCLUSIONS: Both methods have acceptable performance characteristics for use in clinical diagnostic applications. A good comparability was obtained between HPLC and LC-MS/MS methods. However, LoD of HPLC assay was higher and there was a poor correlation between the two systems for samples with 25 (OH) D3 concentrations below 10 ng/mL, showing that LC-MS/MS system is more successful in measuring samples with low 25 (OH) D3 concentration.

A Comparison of hs-CRP Levels in New Diabetes Groups Diagnosed Based on FPG, 2-hPG, or HbA1c Criteria.

Fasting plasma glucose (FPG) and hemoglobin A1c (HbA1c) have been used to diagnose new-onset diabetes mellitus (DM) in order to simplify the diagnostic tests compared with the 2-hour oral glucose tolerance test (OGTT; 2-hPG). We aimed to identify optimal cut-off points of high sensitive C-reactive protein (hs-CRP) in new-onset DM people based on FPG, 2-hPG, or HbA1c methods. Data derived from recent population-based survey in Turkey (TURDEP-II). The study included 26,499 adult people (63% women, response rate 85%). The mean serum concentration of hs-CRP in women was higher than in men (p < 0.001). The people with new-onset DM based on HbA1c had higher mean hs-CRP level than FPG based and 2-hPG based DM cases. In HbA1c, 2-hPG, and FPG based new-onset DM people, cut-off levels of hs-CRP in women were 2.9, 2.1, and 2.5 mg/L [27.5, 19.7, and 23.5 nmol/L] and corresponding values in men were 2.0, 1.8, and 1.8 mg/L (19.0, 16.9, and 16.9 nmol/L), respectively (sensitivity 60-65% and specificity 54-64%). Our results revealed that hs-CRP may not further strengthen the diagnosis of new-onset DM. Nevertheless, the highest hs-CRP level observed in new-onset DM people diagnosed with HbA1c criterion supports the general assumption that this method might recognize people in more advanced diabetic stage compared with other diagnostic methods.

Evaluation of Cell Counting in Body Fluids: Comparison of Two Automated Hematology Analyzers with Manual Microscopy.

BACKGROUND: Manual microscopic analysis (MMA) of body fluids has been widely replaced by automated systems. The aim of this study was to assess the performances of the Sysmex XN-1000 (XN-1000) and UniCel DxH800 (DxH800) for body fluid analysis and compare their results with MMA and with each other. METHODS: Red blood cell (RBC), WBC and WBC-differential counts of 142 body fluid samples (7 cerebrospinal, 28 pleural, 107 ascitic fluids) were performed using DxH800, XN-1000, and MMA. RESULTS: The within-run and between-days CVs% were lower than 10% for both systems except MONO of DxH800. Both analyzers demonstrated good linearity and minimal carry-over. The comparison of the XN-1000 and DxH800 with manual counting and each other revealed good correlation (r > 0.90 for both). CONCLUSIONS: Automated systems introduce standardized and accurate performances to analyze biologic fluids. They are also beneficial for reducing turn-around time and laboratory costs.

Osteoporotic risk and physeal closure in prepubertal ovariohysterectomized cats.

We aimed to examine the early effects of prepubertal ovariohysterectomy (P-OHE) on bone loss and proximal physeal closure in cats. Fourteen kittens randomly underwent P-OHE or sham operations (S-OP) at three months (mo) of age and were allocated to group I and group II. Each mo between four and nine mo of age, dual-energy X-ray absorptiometry (DEXA) scans were performed to determine the total body bone mineral density (BMD) and bone mineral content (BMC). Proximal radial physeal closure and radial length were determined by radiography. Bone-specific alkaline phosphatase (BAP), carboxy-terminal collagen teleopeptide (CTX), 17-ß estradiol, progesterone, calcium (Ca) and phosphorus (P) were measured in the serum samples. No significant differences were observed between the groups in terms of BMD, BMC, BAP, BAP/CTX, P, progesterone and body weight (BW) (between 4 and 9mo) and for Ca (between 5 and 9mo) and for CTX levels (between 4 and 8mo). The 17-ß estradiol was significantly higher at 6, 8 and 9mo of age in the S-OP group due to puberty (P=0.02, P=0.03 and P=0.02 respectively). Although there was a significant difference (P=0.0002) between the P-OHE and S-OP groups in terms of the proximal radial physeal closure times (7.43±0.20mo and 6.14±0.14mo, respectively), no significant difference was observed for the mean radius length (10.59±0.10cm and 10.06±0.27cm, respectively) at the last evaluation time. In conclusion, prepubertal ovariohysterectomized cats do not have any osteoporotic risks until nine mo of age and exhibit a delayed physeal closure time without a change in radius length.

Circulating levels of apelin, glucagon-like peptide and visfatin in hypercholesterolemic-hyperhomocysteinemic guinea-pigs: their relation with NO metabolism.

The aim of this study was to determine the levels of regulatory peptides apelin, glucagon-like peptide (GLP-1) and visfatin in hypercholesterolemic and hyperhomocysteinemic state and to examine their relation with nitric oxide (NO) metabolism. 32 Male guinea pigs were divided into four groups and each group was fed as follows: (a) commercial chow, (b) cholesterol (chol)-rich diet, (c) methionine (meth)-rich diet, and (d) chol + meth-rich diet. Blood samples were drawn at the end of 10 weeks, and abdominal aorta was dissected for histopathological examination. Serum insulin, GLP-1, apelin, visfatin, and nitrotyrosine concentrations were measured by the manufacturer's kits based on ELISA; asymmetric dimethylarginine (ADMA) and arginine levels were measured by the high performance liquid chromatography. Homocysteine level was measured by the chemiluminescence immunoassay; glucose, total chol and triglyceride levels were measured by the autoanalyzer. The microscopic examination of aorta indicated varying degrees of vascular disturbance in chol- and chol + meth-fed groups. High levels of chol and homocysteine, accompanied with significantly low levels of apelin and GLP-1 were detected in the plasma. Visfatin, ADMA, and nitrotyrosine levels both in chol- and chol + meth-fed groups were significantly higher than those in control animals, whereas arginine and arginine/ADMA ratio were lower. This study indicated that circulating levels of apelin, GLP-1, and visfatin are markedly altered during the development of atherosclerotic changes in close association with chol, homocysteine, NO, and ADMA levels. The measurements of these peptides in serum may help for the diagnosis and follow-up of vascular dysfunction.