Endoplasmic reticulum stress and pro-inflammatory responses induced by phthalate metabolites monoethylhexyl phthalate and monobutyl phthalate in 1.1B4 pancreatic beta cells

In recent years, phthalates and their metabolites have been associated with metabolic diseases such as diabetes mellitus. To investigate the effects of phthalate metabolites exposure on insulin production and release, 1.1B4 pancreatic beta cells were treated with different concentrations (0.001-1000 µM) of monoethylhexyl phthalate (MEHP) and monobutyl phthalate (MBP). For such purpose, the 1.1B4 cells were evaluated for their viability, apoptosis rate, lysosomal membrane permeabilization (LMP), mitochondrial membrane potential (ΔΨm), oxidative stress, ER stress status, in addition to their secretory functions. MEHP, not MBP, exhibited a notable reduction in metabolic viability, particularly at higher concentrations (500 and 1000 µM) following 24-hour exposure. Similarly, both MEHP and MBP induced decreased metabolic viability at high concentrations after 48- and 72-hour exposure. Notably, neither MEHP nor MBP demonstrated a significant impact on apoptosis rates after 24-hour exposure, and MBP induced mild necrosis at 1000 µM concentration. Cell proliferation rates, indicated by PCNA expression, decreased with 10 and 1000 µM MEHP and 0.1 and 10 µM MBP exposures. LMP analysis revealed an increase in 1000 µM MBP group. Exposure to 0.001 µM of both MEHP and MBP significantly reduced cellular glutathione (GSH) levels. No significant change in intracellular reactive oxygen species (ROS) levels and ΔΨm was observed, but MBP-exposed cells exhibited elevated levels of lipid peroxidation. Functional assessments of pancreatic beta cells unveiled reduced insulin secretion at low glucose concentrations following exposure to both MEHP and MBP, with concurrent alterations in the expression levels of key proteins associated with beta cell function, including GLUT1, GCK, PDX1, and MafA. Moreover, MEHP and MBP exposures were associated with alterations in ER stress-related pathways, including JNK, GADD153, and NF-κB expression, as well as PPARα and PPARγ levels. In conclusion, this study provides comprehensive insights into the diverse impacts of MEHP and MBP on 1.1B4 pancreatic beta cells, emphasizing their potential role in modulating cell survival, metabolic function, and stress response pathways.

Factors causing stress in women with babies 0-3 months old and their coping styles

This study was conducted in order to identify the factors that cause stress in women who have babies aged 0-3 months and the ways to deal with stress. This descriptive study was conducted in outpatient clinics for newborns. The sample consisted of 322 women. Data were collected through a questionnaire and Ways of Coping with Stress Inventory. It was found that most of the women became stressed because of problems regarding self-care, baby care and social life. Women mostly used ineffective coping styles to cope with stress.

Mobbing against nurses in the workplace in Turkey

AIM

The aim of the study was to determine whether the nurses have been exposed to mobbing or not, and to reveal the causes of the mobbing between 3 November 2008 and 31 December 2008.

METHODS

This research was a mixed method study involving survey and focus group interviews. The sample was calculated using sample calculation formula, and 206 nurses were included in the survey study. Four focus group interviews were later carried out with 16 nurses. The survey method and semi-structured question form were used to collect data. The percentage and chi-square were used to evaluate the quantitative data, and for the analysis of the qualitative data, descriptive analyses were made through direct quotations from the nurses' statements.

FINDINGS

According to the mobbing scale, 9.7% of the nurses had been exposed to mobbing, but according to their own declarations, 33% had been exposed. Some of the nurses (25.2%) who expressed that they had been exposed to mobbing reported that the executor of mobbing was the head nurse and 9.2% said that the reason for mobbing was 'communication problems'. Nurses under 25 years of age and those who work in intensive care units are apparently exposed to mobbing more frequently than others (P<0.05).

CONCLUSIONS

It is suggested that head nurses' mobbing behaviours should be determined and they should be educated about leadership. Nurses should be educated about assertiveness to prevent mobbing. The necessary measures should be adopted to solve the 'communication problems', which are shown as a major reason for mobbing.

Scintigraphic evaluation of paired renal allografts from the same cadaveric donor

The aim of this study was to compare the outcome of paired grafts in renal recipients from the same cadaveric donor using quantitative Tc-99m DTPA scintigraphy. Fifty recipients from 25 cadaveric donors were followed for a median period of 3 years. Serial Tc-99m DTPA scintigraphy was performed starting on the third posttransplant day and images evaluated quantitatively. The quantitative parameters included Hilson's perfusion index, time to maximum activity, time to half of maximum activity, the ratio of the graft activity at 20 to 3 minutes, and glomerular filtration rate. In the early postoperative period, 20 of 25 paired kidneys showed similar performances. At the end of the first year 22 of 25 pairs showed a similar evolution. At the end of the third year, the number was 21 of 25. We concluded that if cold ischemia time was prudent, there was no difference in graft outcome between the first and the second recipient of a renal transplant from the same cadaveric donor.

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.

Circulating interleukin-1 beta, interleukin-6, tumor necrosis factor-alpha, and soluble ICAM-1 in patients with chronic stable angina and myocardial infarction

The changes in serum concentrations of cytokines such as interleukin-1 (IL-1) beta, interleukin-6 (IL-6), tumor necrosis factor (TNF) alpha and a soluble-intercellular adhesion molecule (sICAM-1) has been investigated in patients with stable angina and acute myocardial infarction. Thirty-four patients with stable angina (SA), 15 with acute myocardial infarction (AMI), and 20 subjects in the control (C) group were included in the study. The mean serum concentrations of sICAM-1, IL-1-beta, IL-6, and TNF-alpha differed significantly among the three groups. Serum concentrations of IL-1 beta, sICAM-1, and TNF-alpha were comparable in the AMI and SA groups and higher than those found in the C group (p < 0.001). The serum concentration of IL-6 was more than twice as high in the AMI group as compared to the other two groups (p < 0.001). The mean serum concentrations of IL-1 beta, TNF-alpha, and IL-6 were comparable in the AMI and SA groups and higher than in the C group.

Beneficial effects of iloprost during experimentally induced hemorrhagic shock

BACKGROUND

The aim of the study was to evaluate the efficacy of iloprost on myocardial insufficiency associated with hypovolemic shock in dogs. We designed the study as a controlled randomized study.

METHODS

Sixteen mixed-breed dogs were included into the study and divided into two equal groups as the control and iloprost groups. Mean arterial pressure was reduced to 45 mmHg by withdrawing the arterial blood into citrated bags. The control group did not receive any drug but the other group received iloprost at a rate of 20 ng/kg/min by an infusion pump. Iloprost infusion was started 30 min after the blood pressure was reduced to 45 mmHg. All measurements were made before removal of blood, 45 min after exsanguination and at 1 hour intervals for 3 hours. Left ventricular stroke work index was measured 72 hours after the study. The hemodynamic and biochemical parameters and blood gas analysis were obtained.

RESULTS

After hemorrhage, cardiac index (CI) decreased significantly from 132 +/- 14 to 51 +/- 8 ml/kg/min in the control group and from 128 +/- 11 ml/kg/min to 47 +/- 13 ml/kg/min in the iloprost group, respectively but at the end of the third hour it was 81 +/- 8 ml/kg/min in the control group and 105 +/- 6 ml/kg/min in the iloprost group (p < 0.05). Tumor necrosis factor-alpha (TNF alpha) was 41 +/- 8 pg/ml in the control group and 18 +/- 6 in the iloprost group 3 hours after bleeding (p < 0.05). Tumor necrosis factor-alpha concentration was significantly higher in the control group than in the iloprost group. There was no significant difference in pH between the groups but actual bicarbonate concentrations were different between the groups (p < 0.05). At the end of the third hour total body oxygen consumption was 105 +/- 11 ml/min in the control group and 132 +/- 12 ml/min in the iloprost group (p < 0.05). Oxygen delivery 3 hours after hemorrhage was 201 +/- 19 ml/min in the control group and 252 +/- 24 ml/min in the iloprost group (p > 0.05). Left ventricular stroke work index was higher in the iloprost group (p < 0.05).

CONCLUSIONS

Hemorrhagic shock causes tumor necrosis factor-alpha release which may lead to multiple organ failure. Organ dysfunction still persists even after the appropriate treatment. Iloprost attenuates the release of tumor necrosis factor-alpha which may improve the adverse effects of hemorrhagic shock.

Predictors of left ventricular thrombus formation in patients with anterior myocardial infarction: role of activated protein C resistance

BACKGROUND

Left ventricular mural thrombus formation is a well-recognised consequence of acute anterior myocardial infarction. The vast majority of left ventricular thromboses occur in patients with anterior myocardial infarction and depressed left ventricular function.

OBJECTIVE

To evaluate the factors predicting left ventricular thrombus formation in patients similar for left ventricular function and left ventricular score indexes.

METHODS

We evaluated 45 consecutive patients who met the inclusion criteria of anterior myocardial infarction resulting in apical, anterior or septal asynergy (akinesia, dyskinesia), without non-Q-wave myocardial infarction, dilated cardiomyopathy, or renal or hepatic dysfunction. Patients were divided into two groups: group I with, and group II without, left ventricular mural thrombus. The groups were compared for clinical, echocardiographic and hematologic parameters (activated protein C resistance (APC-R), protein S and antithrombin III).

RESULTS

Smoking and ACP-R were significantly greater in group I than in group II (P < 0.05 and P < 0.005 respectively). Multivariate regression analysis showed that APC-R was an independent risk factor for left ventricular thrombus formation in the patient group selected. Antithrombin III and protein S concentrations were not statistically different between two groups. All other clinical and echocardiographic characteristics of the patients were similar in both groups.

CONCLUSION

APC-R is an independent risk factor for left ventricular thrombosis in patients with anterior myocardial infarction resulting in septal or anterior and apical akinesia or dyskinesia.

Can flow cytometry detect successful ticlopidine treatment in patients with VVI pacemakers?

An increased platelet activation status is present in patients with VVI pacemakers. With platelet activation, there is modulation of platelet surface molecule expression. In the current study, the expression of platelet surface markers in VVI patients before and after ticlopidine treatment and control subjects was investigated by means of flow cytometry. The study group consisted of 25 patients with VVI pacemaker, and 15 control subjects. CD42b, CD61, and CD62p expression were significantly increased in VVI patients compared with control subjects (CD42b p < 0.001, CD61 p< 0.005 and CD62p p < 0.001). In addition, after ticlopidine treatment, platelets showed a significant fall in expression of all these markers in VVI patients (CD42b p < 0.001, CD61 p < 0.005 and CD62p p< 0.001). Our data suggest an increase of the surface expression of all these markers on platelets and demonstrate the efficacy of ticlopidine in reducing them.

Circulating cytokines and complements in chronic heart failure

Elevated levels of cytokines and complements have been reported in patients with advanced heart failure, but the exact clinical significance remains unclear. Therefore, assessments correlated with hemodynamic and clinical variables may provide important insight into the actions of cytokines and complements in chronic heart failure. The authors evaluated the clinical significance of cytokines and complements. The study included 60 subjects (50 men, 10 women); 34 had idiopathic dilated cardiomyopathy (DCM) and 26 had ischemic heart disease (IHD). Tumor necrosis factor alpha and interleukin-2 receptor concentrations in chronic heart failure were greater than in control subjects (20.0 +/- 0.4 vs 18.0 +/- 0.5 pg/mL, p<0.05 and 817.23 +/- 63.50 vs 642.75 +/- 27.31 pg/mL, p<0.05, respectively). There was no significant difference between DCM and IHD patients in circulating levels of the cytokines and the components complements (p=NS). Additionally, although functional classes III and IV heart failure patients showed a tendency to increase the levels of the cytokines and the component complements, these differences were not statistically significant (p=NS). Similarly, correlation analysis showed that the levels of the circulating cytokines and the component complements had independent value for mortality. These results suggest that humoral and cellular immunity abnormalities may play an important role in the pathogenesis of heart failure and dilated cardiomyopathy.

Plasma leukocyte elastase concentration and coronary artery disease

It has previously been shown that leukocyte elastase is involved in the pathogenesis of atherosclerosis. Few studies have addressed the relation between leukocyte elastase concentrations and coronary artery disease (CAD). The authors investigated (1) the clinical significance of leukocyte elastase determination in the diagnosis of CAD and (2) the relation between plasma leukocyte elastase concentration and lesion morphology. The study included 185 subjects (140 men, 45 women) who underwent coronary angiography during investigation of chest pain; 135 had coronary stenosis (Group I) and 50 had nonstenotic coronaries (Group II). Among Group I patients, those with simple atheromatous plaques were distinguished from those with complex plaques. Elastase concentrations in Group I were greater than in Group II (57.1 +/- 1.16 micrograms I[-1] vs 27.6 +/- 1.0 microgram, I[-1], P<0.001), and greater in complex plaque patients than in those with simple plaques (64.5 +/- 1.24 micrograms I[-1] vs 45.9 +/- 1.01 micrograms I[-1], P<0.001). Logistic regression analysis showed (1) that elastase concentration, age, and sex had independent value for prediction of CAD and (2) that among Group I patients, the risk of complex plaques was greatest for those with high elastase concentration. These results suggest that plasma leukocyte elastase concentration is a sensitive diagnostic marker of CAD and that high values of elastase may indicate the presence of complex atheromatous plaques.

Iloprost added to the cardioplegic solutions improves myocardial performance

A total of 12 mongrel dogs were divided into two equal groups. Six animals received IIoprost and the other 6 animals did not receive any additional treatment. In the Iloprost group, Iloprost was added to the cardioplegic solution (25 ng). Also, Iloprost was used (10 ng/kg/min.) 5 min. before and after cross-clamping. All cardiac output and biochemical measurements were evaluated before cross-clamp and 15 min., 1 h, and 4 h after cross-clamp. The measured dp/dt shows that the hearts treated with Iloprost preserved left ventricular function. Comparison of contractility indices between the groups revealed that contractile recovery was 59% in the control group and 71% in the Iloprost group (p < 0.05). Tumor necrosis factor (TNF) alpha level was significantly elevated in the control group (p < 0.001). Its level was 22.2 +/- 2.2 pg/mL in the control group and 13.8 +/- 1.0 pg/mL in the Iloprost group. E- and P-selectin levels were elevated in the control group (p < 0.001). ICAM-1 level was also elevated in the control group. ICAM-1 level was 17.7 +/- 1.8 ng/mL in the control group and 8.5 +/- 1.8 ng/mL in the Iloprost group. The Iloprost that was added to the cardioplegic solution and low dose administration during the pre- and post-ischemic period inhibits the toxic mediator release from endothelium-leukocyte interaction and reduces the severity of ischemia-reperfusion injury.