Interpenetrating polymer networks of poly(dimethylsiloxane) with polystyrene,polybutadiene and poly(glycerylpropoxytriacrylate)

The synthesis of full and semi interpenetrating networks (IPNs) based on poly(dimethy1-siloxane) (PDMS)/polystyrene, PDMS/polybutadiene and PDMS/poly(glycerylpropoxytriacry-late) 1

1 Glycerylpropoxytriacrylate (GFTA):

is described. PDMS was used as host polymer in most cases. PDMS networks were prepared with two prepolymers having different number-average molecular weights between junctions, M?_c = 15 · l0³ and M?_c = 75 · l0³. Physical properties of IPN samples such as stress-strain behaviour, swelling and glass transition temperature (T_g) were examined. IPNs of both PDMS/polystyrene and PDMS/poly(glycerylpropoxytriacrylate) exhibit superior mechanical and elastomeric properties with respect to pure PDMS network. Most of the IPN systems studied in this work display two T_gs and indicate phase separation.     

Alpha-lipoic acid may ameliorate testicular damage by targeting dox-induced altered antioxidant parameters,mitofusin-2 and apoptotic gene expression

In the study, the ameliorating effects of alfa lipoic acid (ALA) against doxorubicin-induced testicular apoptosis, oxidative stress and disrupted mitochondrial fusion were investigated in male rats. Rats were divided into four groups as control, doxorubicin (DOX), DOX + ALA and ALA. A single dose of 15 mg/kg DOX was administered i.p to the DOX and DOX + ALA groups. 50 mg/kg ALA was given to the DOX + ALA and ALA groups by oral gavage every other day. After 28 days, rat testes and serum samples were collected and analysed. Administration of DOX alone caused a decrease in body and relative testicular weights, seminiferous tubule diameter and germinal epithelium thickness, Johnsen's score and serum testosterone levels. DOX treatment led to severe testicular damage such as tubular degeneration, and atrophic tubules. Also, the activities of superoxide dismutase and glutathione peroxidase were reduced, while the level of malondialdehyde was increased in the testis. The mRNA levels of apoptotic-related genes (CASP3, TP53, BAX, BCL2) and apoptotic index were increased, while mitofusin-2 decreased. DOX caused an increase in CASP3 and a decrease in mitofusin-2 immunoreactivities. Treatment with ALA markedly improved all of DOX-induced biochemical, histochemical and molecular alterations in rat testis. Consequently, ALA has a therapeutic role in ameliorating DOX-induced testicular damage in rats.     

Effect of aluminum adjuvants on safety and immunogenicity of Haemophilus influenzae type b-CRM197 conjugate vaccine

OBJECTIVE: The present study was carried out to evaluate the safety and immunogenicity of the Haemophilus influenzae type b-CRM197 (Hib-CRM197) conjugate vaccine in relation to the change of adjuvant from aluminum hydroxide to aluminum phosphate (AlPO4). METHODS: The present study was a clinical phase II, observer-blind, randomized, multicenter, controlled study. Subjects were healthy infants aged 6-12 weeks, eligible for expanded program of immunization (EPI) routine vaccination and admitted to Hacettepe University Department of Social Pediatrics and Gülveren Health Center, Ankara. A total of 520 healthy infants were randomized in a 2:2:1 ratio to receive at either Chiron Hib/AlPO4 vaccine or VaxemHib (aluminum hydroxide adjuvant) vaccine or HibTiter (no adjuvant). Vaccines were administered simultaneously with routine diphtheria, tetanus and pertussis (DTaP) and oral polio vaccine (OPV) vaccines at 2, 4 and 6 months of age. Blood samples for anti-plain polysaccharide (PRP) antibody measurement were collected before the first vaccination and 1 month after the last vaccination. After each vaccination parents filled out a diary for 7 days. RESULTS: Out of 520 subjects enrolled, 514 received three doses and were included for safety analysis. Local and systemic reactions occurred with low and similar frequencies in all groups. Only erythema was more common in Chiron Hib/AlPO4 vaccine (19, 10, 11% in Chiron Hib/AlPO4, VaxemHib and HibTiter, respectively, P < 0.05). Nine serious adverse events were reported in seven cases of which none were related to vaccines. A total of 504 subjects were included in the immunogenicity analysis. The three vaccines were highly immunogenic and equivalent in terms of percentage of acquisition of long-term protective levels. The anti-PRP geometric mean titers were 9.9, 8.3 and 5.14 micro g/mL, respectively (P < 0.05). CONCLUSIONS: The use of aluminum compounds adjuvants in Hib-CRM197 conjugate vaccines does not impact the safety profile, while it does increase the magnitude of anti-PRP antibody titers.     

Hereditary pancreatitis: Report of a family from Turkey

Chronic pancreatitis is a rare disease in children and is usually secondary to underlying diseases such as hereditary pancreatitis, cystic fibrosis, hyperlipidemia, prolonged malnutrition, gallstones or anomalies of the biliary-pancreatic duct system. Hereditary pancreatitis is a common cause of chronic pancreatitis in children but is often unrecognized until months or years later. We report here a family with hereditary pancreatitis in which four members are affected.     

Interaction of topiramate with glycine receptor channels

Glycine receptor channels are pentameric ligand-gated ion channels that respond to the application of inhibitory neurotransmitters by opening of a chloride-selective central pore. Topiramate (TPM) is a broad-spectrum antiepileptic drug used as add-on or monotherapy for focal seizures. In the present study the interaction of TPM with glycine receptor channels was studied on outside-out patches from HEK293 cells expressing alpha1beta glycine receptor channels. The patch clamp techniques combined with ultra fast solution exchange enabled us to investigate the kinetics of receptor channels in presence of TPM. Our study showed no agonistic or potentiating effect for TPM on glycine receptor channels. However, in presence of 1 mM glycine + 1 mM TPM, the desensitization got faster and the peak current amplitude decreased. After the end of glycine + TPM pulses, off-currents occurred, suggestive for a specific channel block mechanism.     

A cluster of nosocomial Klebsiella oxytoca bloodstream infections in a university hospital.

BACKGROUND: On February 19, 2003, four patients (patients 1-4) in the neurology ward underwent cranial magnetic resonance angiography (MRA) and developed fever within 1 hour afterward. Klebsiella oxytoca was isolated from blood cultures of patients 1 through 3. OBJECTIVE: To identify the source of this cluster of nosocomial K. oxytoca bloodstream infections. DESIGN: Outbreak investigation. SETTING: A 1,000-bed university hospital. METHODS: The infection control team reviewed patient charts and interviewed nursing staff about the preparation and administration of parenteral fluids. The procedure of cranial MRA was observed. Arbitrarily primed polymerase chain reaction (AP-PCR) was performed to show the clonal relationship among these three strains. RESULTS: AP-PCR revealed that three K. oxytoca isolates had the same molecular profile. Cranial MRA was found to be the only common source among these patients. During MRA, before injection of the contrast medium, normal saline solution was infused to check the functioning of the intravenous catheter. Use of the solution for multiple patients was routine, but the access diaphragm of the bottle was not cleansed. The bottle of normal saline solution used on February 19 had already been discarded and the culture sample taken from the solution on the day of observation was sterile. CONCLUSIONS: We speculate that normal saline solution became contaminated during manipulation and that successive uses might have been responsible for this cluster. Poor aseptic techniques employed during successive uses appear to be the most likely route of contamination. Use of parenteral solutions for multiple patients was discontinued.     

Maternal mortality rates in the last eight years: A university hospital-based study from Turkey.

OBJECTIVE: To analyze the cause of changing maternal mortality ratios (MMRs) in a tertiary women's health center in Turkey in the last eight years. MATERIALS AND METHODS: Charts of patients seen between 1998 and 2005 were retrospectively reviewed. Statistical analysis was performed using the Chi-square test. The results were accepted to be significant when the p value was <0.05. RESULTS: During this period, 27 pregnancy-related deaths were identified via hospital death records. The MMR was found to have decreased in rate by approximately 50% from 822.2/100,000 live births in the previous report including the years 1978-1997 to 412.0/100,000 during the last eight years (p < 0.01). Pregnancy-induced hypertension was still the most frequent cause of maternal death. The decrease in MMR was due to the decrease in the ratio of maternal infection (26.4% in 1978-1997 to 7.4% in 1998-2005, p < 0.01). CONCLUSION: Although treatment in the antenatal care and health service has decreased maternal deaths, it was discovered that the MMR has not reached the optimum levels found in developed countries in the last eight years. Also the percentage of direct obstetric deaths (with the exception of those caused by infection) showed no change and was similar to that found in the previous report (1978-1997).     

Prognostic factors that affect survival after the treatment of early stage cervical carcinoma

The aim of this study was to investigate the presence of risk factors for predicting survival and to evaluate the efficacy of the radical surgery in patients with early stage cervical carcinoma. A total of 200 women who underwent radical hysterectomy and bilateral pelvic lymph node dissection for early stage cervical carcinoma were retrospectively analysed. We found that lymph node involvement (P <0.0015) and lymphovascular invasion (P <0.05) were the best prognostic factors for disease-free survival in our cases. The depth of cervical invasion, lymphovascular invasion and parametrial spread were closely related with lymph node involvement. Parametrial spread was shown in 38 patients (19%), assessed as stage Ia-IIa pre-operatively. Seventy-six stage Ib patients, at high-risk of recurrence, received adjuvant radiotherapy. Although there was some local tumour recurrence in the control group, adjuvant radiotherapy did not improve the overall survival in stage Ib patients. As a consequence, primary surgery would be definitive in estimating survival from histopathological evaluation. This study demonstrates that lymph node involvement and lymphovascular space infiltration were the best predictor factors for survival.