Clay‐PMMA Nanocomposites by Photoinitiated Radical Polymerization Using Intercalated Phenacyl Pyridinium Salt Initiators

Summary: In situ synthesis of poly(methyl methacrylate) (PMMA) nanocomposites by photopolymerization using organophilic montmorillonite (MMT) as the layered clay is reported. MMT clay was ion exchanged with N‐phenacyl, N,N‐dimethylanilinium hexafluoro phosphate (PDA) which acts as both suitable intercalant‐ and photo‐initiator. These modified clays were then dispersed in methyl methacrylate (MMA) monomer in different loading degrees to carry out the in situ photopolymerization. Intercalation ability of the photoinitiator and exfoliated nanocomposite structure were evidenced by both X‐ray diffraction (XRD) spectroscopy and transmission electron microscopy (TEM). Thermal properties and morphologies of the resultant nanocomposites were also studied.

Schematic representation of clay‐PMMA nanocomposites by photoinitiated radical polymerization.     

Acaricidal efficacy of <Emphasis Type="Italic">Origanum onites</Emphasis> L. essential oil against <Emphasis Type="Italic">Rhipicephalus turanicus</Emphasis> (Ixodidae)

Essential oils that were extracted by steam distillation from Origanum onites L. from northwest Turkey were analyzed using an Agilent GC-MSD system. Carvacrol was the major component (64.3%) of the oil. Both pure commercial carvacrol and essential oil at concentrations of 1.5%, 3.2%, 6.25%, 12.5%, 25%, 50%, and 100% (v/v) were tested for their effects against engorging Rhipicephalus turanicus, which were collected from cattle breeding in the region. Pure carvacrol killed all the ticks following 6 h of exposure, while 25% and higher concentrations of the oil were completely effective in killing the ticks by the 24th-hour post-treatment (p < 0.05). The concentrations of 6.25% and 12.5% killed all the ticks by day 2. Lethal concentrations for 50% (LC(50)) and 90% (LC(90)) of 2.34% and 7.12%, respectively, were detected 24 h post-treatment. These findings indicate that the essential oil of O. onites L. has potential to be utilized at reasonable concentrations to control tick infestations.     

Serum endothelin-1 and placental alkaline phosphatase levels in placenta percreta and normal pregnancies

Purpose: To evaluate the circulatory levels of endothelin 1 (ET-1) and the placental alkaline phosphatase (ALP) in pregnant women with placenta percreta (PP) and a control group.

Methods: This study was carried out in the Obstetrics and Gynecology and in the Biochemistry Departments of Harran University Medical School. Forty-four women who underwent cesarean section (CS) due to PP and 44 women who underwent CS for other obstetric reasons were included in this study. The PP diagnosis was made by a pathologic examination that showed an extreme trophoblastic invasion involving the uterine serosa.The levels of circulating ET-1 and placental ALP were measured by an enzyme-linked immunosorbent assay (ELISA).

Results: Women with PP more frequently received antenatal steroids and blood transfusions and they delivered at an earlier gestational age compared to controls. In women with PP, preoperative circulating ET-1 and placental ALP levels were lower than in the controls (p?Conclusions: The findings suggest that a decrease in ET-1 and placental ALP levels might play a role in the pathogenesis of PP.     

An analysis of salivary gland neoplasms: a 12-year, single-institution experience in Turkey

The epidemiology of salivary gland tumors worldwide is not very well defined. Although many studies on this subject have been undertaken, the data are generally focused on specific topics such as parotid gland neoplasms or tumors of the major salivary glands. We conducted a study to establish the prevalence and distribution of benign and malignant neoplasms of both the major and minor salivary glands at a single institution. We reviewed 244,204 cases that had come through our pathology department from January 1994 through December 2005 and found 235 cases of a salivary gland neoplasm (0.09%). The female-to-male ratio was 1.04:1, and the mean age of the patients was 47 years. Of the 235 neoplasms, 159 (67.66%) were located in the parotid gland, 34 (14.47%) in the submandibular gland, and 42 (17.87%) in the minor salivary glands. A total of 146 tumors (62.13%) were benign and 89 (37.87%) were malignant. Pleomorphic adenoma was the most common neoplasm, occurring in 98 cases (41.70%). The most common malignancy was mucoepidermoid carcinoma, with 27 cases (11.49%). Our data demonstrate that the characteristics of salivary gland tumors in a Turkish population at a single institution are similar to those reported in the literature worldwide.     

Carcinoma Arising from Villous Adenoma of the Ampullary Bile Duct: Report of a Case

Adenocarcinoma arising from the villous adenoma of the ampullary biliary epithelium is an extremely rare disorder. The preoperative diagnosis and treatment of the disease represent a major difficulty. A 67-year-old woman was admitted to the hospital with a chief complaint of jaundice. Preoperative investigations revealed obstructive type jaundice due to a 2-cm mass at the end of common bile duct. She was operated on and after undergoing a sphincterotomy, small, yellowish, grape-like particles fell down from the ampullar orifice. A frozen-section examination of these particles revealed villous adenoma. Next, a transduodenal resection of ampulla and reconstruction were performed. The frozen-section examination of the resected material also revealed a villous adenoma. The patient was discharged uneventfully. The histological examination revealed a villous adenoma arising from the biliary epithelium and some adenocarcinoma foci. The surgical margins were tumor free. Nevertheless, she developed hepatic metastases 15 months after surgery. This case shows the importance of surgeons to keep in mind the fact that frozen examinations may sometimes miss a malignancy and they therefore cannot be relied upon to rule out malignancy in villous adenoma of the ampullary bile duct. This case was presented as a poster presentation at the 12th World Congress of the International Association of Surgeons and Gastroenterologists, Istanbul, Turkey, October 31–November 4, 2002.     

An electrocardiographic algorithm for determining the location of pacemaker electrode in patients with right bundle branch block configuration during permanent ventricular pacing

The expected morphology of right ventricular pacing is a left bundle branch block (LBBB) pattern. However, right bundle branch block (RBBB) can also be seen during permanent right ventricular pacing. The aim of this study was to develop an electrocardiographic algorithm to differentiate this benign condition from septal and free wall perforation with subsequent left ventricular pacing. Three hundred consecutive patients who had permanent ventricular or dual-chamber pacemaker implantation between 1999 and 2000 were screened and 25 patients (8.3%) who exhibited RBBB configuration were included in the study. Echocardiograms and chest radiographs were evaluated in order to identify the pacing lead location in this group. The authors formed a study group with their own 25 patients and 22 cases of RBBB with permanent pacemaker from previous publications (total 47 patients). Frontal axis, QRS morphology in lead V(1), and the precordial transition point, which is defined as the precordial lead where R wave amplitude is equal to S wave amplitude, were examined. Placement of precordial leads V(1) and V(2) 1 interspace lower than the standard location (Klein maneuver) eliminated the RBBB pattern in 12 patients. RBBB pattern with "true right ventricular pacing" was detected in 24 of the 25 patients, and in 11 of the 22 patients reported in the literature (total 35 patients). Right ventricular pacing was correctly identified in 34 of 35 patients with use of criteria including left superior axis deviation, RS or qR morphology in lead V(1), and precordial transition at lead V(3) with a high sensitivity and specificity. A simple surface electrocardiogram can accurately predict the lead location in patients having RBBB morphology with right ventricular pacing.     

Significance of cagA status and vacA subtypes of Helicobacter pylori in determining gastric histopathology: virulence markers of H. pylori and histopathology

BACKGROUND: It has been suggested that Helicobacter pylori strains containing the cytotoxin-associated gene A (cagA), and s1m1 genotype of vacuolating cytotoxin gene A (vacA) may have been associated with peptic ulcer disease. The aim of the present study was to analyze such an association of cagA presence and vacA subtypes of H. pylori with histopathological findings in patients with gastritis. METHODS: Sixty-five independent H. pylori strains isolated from Turkish patients with gastritis were analyzed. The antral biopsy specimens were processed for culture and histopathology. Histopathological features were recorded and graded according to updated Sydney system. The vacA subtypes and cagA gene were tested by polymerase chain reaction. RESULTS: Mild degree of antral density was associated with mild degree of gastric neutrophil infiltration (P = 0.010). Positive cagA status correlated significantly with the presence of atrophy (P = 0.035) and neutrophil infiltration (P < 0.001), but not with H. pylori density (P = 0.754) nor the degree of mononuclear cell infiltration (P = 0.945). The vacA subtypes were independent of gastric histopathology. The odds ratios for atrophy and neutrophil infiltration of cagA+ versus cagA- strains were 3.62 (95% confidence interval [CI]: 1.04-12.66) and 53.18 (95%CI: 11.08-255.23), respectively. CONCLUSION: The presence of the cagA gene is strongly associated with atrophic and active gastritis. Distinct vacA subtypes of H. pylori appear to have no association with histopathological findings of gastritis.     

Is the clinical presentation different between men and women admitting to the sleep laboratory?

Objectives  Sleep and sleep disorders are different in several important ways between men and women. We aimed to investigate gender differences in initial symptoms and associating medical diseases of patients admitting to our sleep clinic. Methods  Ninety-one patients, 20 women (22%) and 71 men (78%), admitting consecutively to the sleep clinic were studied. A detailed sleep and medical history of the patients was recorded. All patients were questioned for Epworth Sleepiness Scale (ESS) and underwent an entire night of diagnostic polysomnography. Apnea–hypopnea index (AHI) was identified as the total number of apnea and hypopnea per hour of sleep. Hypopnea was defined as a decrease of airflow by at least 50% and desaturations were defined as ≥4% decrease in oxygen saturation. Results  The mean values for age, body mass index, blood pressures and ESS score did not significantly differ between men and women, but AHI (events/h) was significantly higher in men (29.1 ± 22.7) than women (17.9 ± 17.7, p < 0.05). Snoring was the most common symptom in both men (95%) and women (90%). Among the main presenting complaints, only morning headache (12 of women 60%, 31 of men 43%, p = 0.04) and dry mouth on awakening (ten of women 50%, 57 of men 80%, p = 0.02) showed a significant difference between the two genders, while among the medical diseases only hypothyroidism (four of women 20% and three of men 4%, p = 0.03) and depression (nine of women 45% and 16 of men 22%, p = 0.02) were seen as statistically higher in women than in men. Conclusions  Primary care physicians should be aware of obstructive sleep apnea (OSA) in women and the importance of referring women for sleep studies when they complain of symptoms associated with OSA, even if other non-specific symptoms such as morning headaches are reported. Also, hypothyroidism and depression are accompanied with sleep disorders especially in women.