Ten (41.7%)

patients had complications perioperatively or during the follow-up. Seven (29.2%) patients had wound complications.

Conclusion. Considering the acceptable local recurrence rate, conservative surgery aided by effective control of intraoperative hemorrhage should be considered as an alternative procedure for patients with giant cell tumors of the sacrum. The advantages include lower morbidity, reduced neurologic deficits, speed and ease of the surgical procedure, reduced blood loss, preservation of spinal and pelvic continuity, and a low recurrence rate.”
“Dogs suffering from Golden Retriever muscular dystrophy (GRMD) present symptoms that are similar to human patients with https://www.selleckchem.com/products/z-devd-fmk.html Duchenne muscular dystrophy (DMD). Phenotypic variability is common in both cases and correlates with disease progression and response to therapy. Physical therapy assessment tools were used to study disease progression and assess phenotypic variability in dogs with GRMD. At 5 (TO), 9 (T1), 13 (T2) and 17 (T3) months of age, the physical features,

joint ranges of motion (ROM), limb and thorax circumferences, weight and creatine kinase (CK) levels were assessed in 11 dogs with GRMD. Alterations of physical features were higher at 13 months, and different disease progression rates were observed. Passive ROM decreased until 1 AZD6738 order year old, which was followed by a decline of elbow and tarsal ROM. Limb and thorax circumferences, which were corrected for body weight, decreased significantly between TO and T3. These measurements can be used

to evaluate disease progression in dogs with GRMD and to help discover new therapies for DMD patients. selleck inhibitor (C) 2011 Elsevier Ltd. All rights reserved.”
“Study Design. Analysis of patient and surgeon preference between selective and nonselective thoracic spinal fusions.

Objective. The purpose of this study was: (1) to determine patient preference between a longer, straighter fusion versus a shorter fusion with a residual lumbar deformity, and (2) to determine surgeon preference based on a cross-sectional survey.

Summary of Background Data. In the surgical treatment of Lenke 1B and 1C curves, choosing between a selective thoracic fusion which may leave residual lumbar deformity versus a fusion into the lower lumbar spine which may improve correction at the expense of lumbar motion continues to be debated.

Methods. The deformity-flexibility quotient (DFQ) was defined to quantify the 2 primary yet competing goals of adolescent idiopathic scoliosis surgery, and is calculated by dividing the residual coronal lumbar deformity by the number of unfused distal motion segments. Patient preference between a selective versus nonselective fusion was determined using a Spearman’s Rho analysis to correlate radiographic data (including the DFQ) with Scoliosis Research Society-24 scores. Surgeon preference was determined using a cross-sectional survey of 12 experienced scoliosis surgeons.

Results.

Good agreement of our new theory with experiment is obtained. The contrast characteristics in energy-filtered secondary electron images are also explained. The results of this work lead to a more advanced understanding of the doping contrast mechanisms, thereby enabling quantitative dopant profiling using the SEM. (C) 2011 American Institute of Physics. [doi:10.1063/1.3524186]“
“PURPOSE: To assess the predictability, efficacy, safety, and stability of collagen copolymer toric phakic intraocular lens (pIOL) implantation to correct moderate to high myopic astigmatism

SETTING: Fernandez-Vega Ophthalmological Institute, Oviedo, Spain

METHODS: This study

comprised eyes that had implantation of a toric Intraocular Collamer Lens for moderate

to high Belnacasan research buy myopic astigmatism The uncorrected (UDVA) and Etomoxir datasheet corrected (CDVA) distance visual acuities. refraction, pIOL vault, and adverse events were evaluated over 12 months

RESULTS: Preoperatively, the mean sphere in the 55 eyes was -4.65 diopters (D) +/- 3.02 (SD) (range -050 to -12.50 D) and the mean cylinder, -3.03 +/- 0.79 D (range -1 25 to -4.00 D) At 12 months, the mean Snellen decimal UDVA was 0 80 +/- 0 20 and the mean CDVA, 0 85 +/- 0 18; 62.0% of eyes had a CDVA of 20/20 More than 500% of eyes gained 1 or more lines of CDVA. The treatment was highly predictable for spherical equivalent (SE) (r(2) = 0 99) and astigmatic components J0 (r(2) = 0 97) and J45 (r(2) = 0 99) Of the eyes, 94.5% were within +/- 0.50 D of the attempted SE and all were within +/- 1.00 D For J0, 94.5% of eyes were within +/- 0.50 D and for J45, 98 2% of eyes; all eyes were within +/- 1.00 D The efficacy index was 0 95 at 3 months and 1.08 at 1 year.

CONCLUSIONS: The UDVA and CDVA with tom pIOLs were good and highly stable over 12 months, confirming the procedure is safe, predictable, and FRAX597 ic50 effective for correction of moderate to high astigmatic”
“Nicotinamide (NAM) is often added in fortified infant and various food products to ensure an adequate

consumption of vitamin. Thus, a proper monitoring of NAM content in foods can be important. In this study, a selective molecularly imprinted polymer as sorbent for solid phase extraction of NAM in animal sources was successfully developed. The molecularly imprinted polymer was synthesized by bulk polymerization technique. The performances of this polymer as sorbent were investigated in NAM standard solutions. One hundred milligrams of polymer was able to retain up to 244 jig of NAM with recovery > 80% when chloroform was used as loading and washing solvent and ethanol as eluting solvent. Other solvent mixtures were also tested. The optimal molecularly imprinted solid phase extraction protocol was defined and used for the clean-up of NAM in pork liver samples.

Conclusions: We conclude that pulmonary injury NVP-BSK805 order is the immediate cause of death in one third of patients with PM/DM; acute exacerbation of chronic interstitial lung disease and bronchopneumonia were the most common specific causes. Immediate cause of death was not established ante-mortem in nearly one third of cases, and some of these causes were treatable.”
“SETTING: Forty-two community and general hospitals in central Thailand.

OBJECTIVE:

To examine the adequacy of indoor ventilation for nosocomial tuberculosis (TB) prevention in public hospitals in central Thailand.

DESIGN: A cross-sectional survey was conducted among 323 patient care and ancillary areas in the target hospitals. Data on indoor ventilation rate were collected by the tracer gas method and reported as air changes per hour (ACH). The adequacy of the measured ventilation rates were then determined by comparison

with the international recommended standard AZD8055 in vivo values.

RESULTS: Indoor ventilation rates were inadequate in almost half of the studied areas (1.44/323, 44.6%). The inadequacy was particularly serious in the emergency rooms (ERs) and radiological areas, where 73.8% (31/42 each) of the rooms had ACH below the recommended standards. Detailed analysis showed that most of the rooms with natural ventilation had air exchange rates that exceeded the recommended standards, while the opposite was the case for rooms with air-conditioning, particularly the window or wall-mount type.,

CONCLUSION: Indoor ventilation in high-risk Sapanisertib in vivo nosocomial TB areas in public hospitals. in Thailand was inadequate due to the installation of air-conditioning systems in modern buildings.”
“Brain tumors are the leading cause of cancer-related

death in children. High-grade astrocytomas (HGAs), in particular, are lethal in children across all ages. Integrative genome-wide analyses of the tumor’s genome, transcriptome and epigenome, using next-generation sequencing technologies and genome-wide DNA methylation arrays, have provided valuable breakthroughs in our understanding of the pathogenesis of HGAs across all ages. Recent profiling studies have provided insight into the epigenetic nature of gliomas in young adults and HGAs in children, particularly with the identification of recurrent gain-of-function driver mutations in the isocitrate dehydrogenase 1 and 2 genes (IDH1/2) and the epigenetic influence of their oncometabolite 2-hydroxyglutarate, as well as mutations in the histone 3 variant 3 gene (H3F3A) and loss-of-function mutations in the histone 3 lysine 36 trimethyltransferase gene (SETD2).

We also provided a mathematical model to quantitatively interpret the observed growth dynamics. Bafilomycin A1 nmr (C) 2011 American Institute of Physics. [doi:10.1063/1.3668243]“
“One

of the well-known needs of teenagers and young adults with cancer (TYAs) is their quest for knowledge about their illness and its treatment. As well as this they desire to be treated as partners and as an integral part of the team who care for them.

This small exploratory study aims to address these issues in the development of a unique project where the young people were given unprecedented access to their own cancer samples and to the professional experts who analyse those samples.

This small cohort of 31 TYAs, aged 13-24 years, were invited to look at their samples under a microscope and discuss it with the experts: IPI-145 inhibitor of these 4 declined. A number of questionnaires, containing both open and closed questions, were given before, immediately post and one month after the viewing session. The results were analysed using SPSS13 and content analysis.

The study was able to establish that viewing cancer samples had no measurable effect on the TYAs gaining of new knowledge, sense of control or choices that they made. However, it did show how the young people felt in light of actually ‘seeing’

their own cancer, and how this seemed to improve the overall perception of their disease. This is a new body of knowledge that requires further, more detailed, rigorous work. (C) 2009 Elsevier Ltd. All rights reserved.”
“AimsTo develop a means to measure the quality of care provided to women treated for urinary incontinence (UI) through the development of quality-of-care indicators (QIs).

MethodsWe performed an extensive literature review to develop a set of potential quality

indicators for the management of UI. QIs were modeled after those previously described in the Assessing the Care of Vulnerable Elders (ACOVE) project. Nine experts ranked the indicators on a nine-point scale for both validity and feasibility. We analyzed preliminary rankings of each indicator using the RAND Appropriateness Batimastat cell line Method. A forum was then held in which each indicator was thoroughly discussed by the panelists as a group, after which the indicators were rated a second time individually using the same nine-point scale.

ResultsQIs were developed that addressed screening, diagnosis, work-up, and both non-surgical and surgical management. Areas of controversy included whether routine screening for incontinence should be performed, whether urodynamics should be performed before non-surgical management is initiated, and whether cystoscopy should be part of the pre-operative work-up of uncomplicated stress incontinence. Following the expert panel discussion, 27 of 40 potential indicators were determined to be valid for UI with a median score of at least seven on a nine-point scale.

(C) 2012 American

Institute of Physics. [doi:10.1063/1.3670362]“
“Objective: The aim of this study was to compare the responsiveness of various patient-reported outcome measures (PROMs) and clinician-reported outcomes following total knee arthroplasty (TKA) over a 2year period.

Methods: Data were collected in a prospective cohort study of primary TKA. Patients who had completed Forgotten Joint Score-12 (9S-12), Western Ontario and McMaster Universities click here (WOMAC) osteoarthritis (OA) index, EQ-5D, Knee Society Score and range of movement (ROM) assessment were included. Five time points were assessed: pre-operative, 2 months, SNDX-275 6 months, 1 year and 2 years post-operative. Results: Data from 98 TKAs were available for analysis.

Largest effect sizes (ES) for change from preoperative to 2-month follow-up were observed for the Knee Society Score (KSS) Knee score (1.70) and WOMAC Total (-1.50). For the period from 6 months to 1 year the largest ES for change were shown by the FJS-12 (0.99) and the KSS Function Score (0.88). The EQ-5D showed the strongest ceiling effect at 1year follow-up with 84.4% of patients scoring the maximum score. ES for the time from 1- to 2-year follow-up were largest for the FJS-12 (0.50). All other outcome measures showed ES equal or below 0.30. Conclusion: Outcome measures differ considerably in responsiveness, especially beyond one year postoperatively. joint-specific

outcome measures are more responsive than clinician-reported or this website generic health outcome tools. The FJS-12 was the most responsive of the tools assessed; suggesting that joint awareness may be a more discerning measure of patient outcome than traditional PROMs. (C) 2013 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.”
“Background: The etiology of Kashin-Beck disease, an endemic osteochondropathy, is unknown. Environmental factors, including selenium deficiency, have been proposed as potential risk factors, but the onset and frequency of this disease vary among groups with similar environmental exposures. Some cases of osteoarthritis that share similar pathological features with Kashin-Beck disease have been associated with specific chromosomal short tandem repeats. In order to better understand the pathogenesis of Kashin-Beck disease, we examined fifteen short tandem-repeat loci on chromosomes 2 and 11 in patients and control subjects, and assessed the interaction between genetic variants and selenium deficiency.

Mean PBDE concentrations ranged from 6.4 ng/g lipid Selleckchem PHA-739358 weight (1w) in squid to I IS ng/g 1w in flounder. BDE 47 was the dominant congener, followed by BDE 100. Mean levels of MeO-PBDEs (sum of congeners 2′-MeO-BDE 68 and 6-MeO-BDE 47) were as high as 110 ng/g lw in tailor, with a slight dominance of 2′-MeO-BDE 68. Polybrominated hexahydroxanthene derivates (PBHDs), another class of naturally-produced compounds, were found at variable concentrations and ranged from 4.7 ng/g lw in fanbelly and 146 ng/g 1w in tailor. The tribrominated PBHD isomer dominated in the samples, except for luderick and squid. The lower levels of PBDEs found in luderick

from the harbour compared to those obtained from the upper Parramatta River indicated a terrestrial (anthropogenic) origin of PBDEs, while the higher levels of MeO-PBDEs and PBHDs in the samples from the harbour confirmed the PFTα in vivo marine (natural) origin of these compounds. The highest trophic magnification factor (TMF) was found for sum PBDEs (3.9), while TMFs for sum MeO-PBDEs and sum PBHDs were 2.9 and 3.4, respectively. This suggests that biomagnification occurs in the studied aquatic food chain

for anthropogenic brominated compounds, but also for the naturally-produced organobromines. (C) 2009 Elsevier Ltd. All rights reserved.”
“Objective: To investigate the effect of temperature on first trimester free beta-hCG and PAPP-A in serum during transportation. Methods: Maternal blood was collected from 30 East Asian women attending for Down syndrome screening at the

primary obstetrical site. The extracted serum was split into two equal aliquots, placed in identical thermally insulated pouches with a temperature data logger and shipped to the screening laboratory. An 800 g frozen ice pack was placed in one of the pouches. Free beta-hCG and PAPP-A levels were determined in the ‘Cooled’ and ‘Uncooled’ serum samples using a DELFIA (R) Xpress analyzer. Z-IETD-FMK mouse The proportion of ‘Uncooled’ samples not within 5% of the ‘Cooled’ sample marker level was assessed. Results: The median age of subjects was 36 years, half were nulliparous and all were non-smokers. The assay stability ranged from 2.38% to 4.41%. The median total transport time from the obstetrical site to the laboratory was 17.37 h. Median recorded temperatures within the ‘Cooled’ pouch were significantly lower throughout the transportation of the samples (p < 0.0001). The median percentage change of free beta-hCG and PAPP-A concentrations in ‘Uncooled’ samples relative to ‘Cooled’ samples were 2.72% (range 0.27-7.64%) and 1.10% (range 0.03%-4.29%), respectively. Free beta-hCG concentrations differed by greater than 5% in eleven (37%) subjects.

S. sites. Participants completed a validated measure of perceived discrimination and reasons for believing that they were treated differently, along with Pap smears, clinical breast exams (CBE), and mammography at each follow-up period. We used multiple logistic regression for the binary outcomes of having a Pap smear, CBE, or mammogram in each of the two follow-up years, using self-reported race discrimination and other discrimination at baseline as the main predictors. Results: African American women reported the highest percentage of racial discrimination (35%), followed by Chinese (20%), Hispanic (12%), Japanese

(11%), and non-Hispanic white women (3%). Non-Hispanic white women reported the highest percentage of other discrimination (40%), followed by Chinese

(33%), African American (24%), Japanese (23%), and Hispanic women (16%). Perceived Citarinostat inhibitor racial discrimination was not associated with reduced receipt of preventive screening, except in one fully adjusted model. AZD1390 purchase Reported discrimination owing to other reasons, such as age or gender, was associated with reduced receipt of Pap smear (odds ratio [OR] 0.85; 95% confidence interval [CI] 0.74-0.99), CBE (OR 0.78; 95% CI 0.67-0.91), and mammography (OR 0.80; 95% CI 0.69-0.92) regardless of patient race. Conclusions: Perceived discrimination is an important issue across racial/ethnic groups and is negatively associated with receipt

of breast and cervical cancer screening. This is an important issue that needs to be further explored and addressed in efforts to improve Selleck LEE011 the delivery of healthcare to all groups.”
“Objective: The relation between vitamin D and autoimmune disorders has long been investigated regarding the important roles of this hormone in immune regulation. We evaluated 25-hydroxyvitamin D (25OHD) status in subjects with Hashimoto’s thyroiditis (HT) and healthy controls.

Methods: Group-1 included 180 euthyroid patients (123 females/57 males) with HT who were on a stable dose of L-thyroxine (LT). A total of 180 sex-, age-, and body mass index (BMI)-matched euthyroid subjects with newly diagnosed HT were considered as Group-2, and 180 healthy volunteers were enrolled as controls (Group-3). All 540 subjects underwent thyroid ultrasound and were evaluated for serum 25OHD, anti-thyroid peroxidase (anti-TPO), and anti-thyroglobulin (anti-TG) levels.

Results: Group-1 had the lowest 25OHD levels (11.4 +/- 5.2 ng/mL) compared to newly diagnosed HT subjects (Group-2) (13.1 +/- 5.9 ng/mL, P = .002) and to control subjects (15.4 +/- 6.8 ng/mL, P<.001). Serum 25OHD levels directly correlated with thyroid volume (r = 0.145, P<.001) and inversely correlated with anti-TPO (r = -0.361, P<.001) and anti-TG levels (r = -0.335, P<.001). We determined that 48.3% of Group-1, 35% of Group-2, and 20.

Furthermore, data fitting using CX-6258 chemical structure Dixon and Lineweaver-Burk plots showed that the inhibition of glycyrrhetinic acid towards UGT2B15 was best fit to competitive type. The second plot using the slopes from Lineweaver-Burk plots vs. glycyrrhetinic acid concentrations was employed to calculate the inhibition kinetic parameters (K-i), and the values were calculated to be 0.35 mu M for UGT2B15. All these

results remind us the possibility of UGT2B15 inhibition-based licorice-drug interaction.”
“To explore how patients with sciatica rate the ‘bothersomeness’ of paresthesia (tingling and numbness) and weakness as compared with leg pain during 2 years of follow-up.

Observational cohort study including 380 patients with sciatica and lumbar disc herniation referred to secondary care. Using the Sciatica Bothersomeness Index paresthesia, weakness and leg pain were rated on a scale from 0 to 6. A symptom

score of 4-6 was defined as bothersome.

Along with leg pain, the bothersomeness of paresthesia and weakness both improved during follow-up. Those who received surgery (n = 121) reported larger improvements in both symptoms than did those who were treated without surgery. At 2 years, 18.2 % of the patients reported bothersome paresthesia, 16.6 % reported bothersome leg pain, and 11.5 % reported bothersome weakness. Among patients with no or little leg pain, 6.7 % reported bothersome paresthesia and 5.1 % bothersome weakness.

During 2 years of follow-up, patients considered paresthesia more bothersome than weakness. At BVD-523 clinical trial 2 years, the percentage of patients who reported bothersome paresthesia

was similar to the percentage who reported bothersome leg pain. Based on patients’ KU-55933 self-report, paresthesia and weakness are relevant aspects of disc-related sciatica.”
“Background: Prophylactic systemic antibiotics significantly lower the risk of postoperative infection, and injection of antibiotics directly into the wound cavity has been found to be even more effective. In this study, we investigated the efficacy of direct injection of antibiotics into a wound cavity after wound closure, both alone and in combination with systemic administration of antibiotics. We hypothesized that a combination of preoperative systemic administration and postoperative local injection would be the most effective treatment.

Methods: Rats were divided into six treatment groups: no treatment, local gentamicin, systemic cefazolin, local cefazolin, systemic cefazolin plus local gentamicin, and systemic cefazolin plus local cefazolin. A wound cavity was opened along the femur, an implant was placed, and the wound was inoculated with 2.5 x 10(8) colony forming units of Staphylococcus aureus. Systemic antibiotics were injected subcutaneously thirty minutes before the initial incision. Local antibiotics were injected percutaneously into the wound cavity after closure.

During the initial course of oxidation at 900 degrees C, the pyrophosphate film transforms into a TiO(2) solid solution containing phosphorus. This transformation impedes the usual oxides external growing mechanisms and leads to an

internal development of the oxide scale with an associated reduced oxidation rate. (C) 2009 American Institute of Physics. [doi:10.1063/1.3257114]“
“Background Postdural puncture headache (PDPH) is a relatively common complication after lumbar punctures (LP). If conservative treatment is not sufficient within a few days and the symptoms are severe, an epidural blood patch (EBP) may be performed. Aim A chart review to evaluate the need and effectiveness of EBPs in children Belnacasan mouse and adolescents over a 10-year period at Kuopio University Hospital (KUH) and Satakunta Central Hospital (SCH).

Methods selleck screening library The information system patient measures databases were reviewed to identify patients who had received an EBP. Then, the pediatric patients’ medical records were compared

to the characteristics of the PDPH and associated symptoms and were evaluated for the effectiveness of EBPs.

Results Forty-two EBPs were performed in 41 patients (24 girls, 17 boys), 26 at KUH and 15 at SCH. Five patients, all at KUH, were children aged 312 years, and 36 patients were adolescents, aged 1318 years. The indications for LPs were diagnostic (n = 26), spinal anesthesia/analgesia (n = 11), or introduction of chemotherapy (n = 2), and four patients developed PDPH after an inadvertent dural puncture

with an epidural needle. The first EBP provided a complete relief of symptoms in 37 children, an initial success rate of 90%, and permanent relief in 85%. At KUH, the need for EBPs after spinal anesthesia/analgesia was <1/1000 in children and 23/1000 in adolescents, and that after chemotherapy 12/1000. No serious adverse effects related to EBPs were recorded.

Conclusion If PDPH symptoms are severe and are not relieved with conservative treatment, EBP is a highly effective procedure in pediatric patients.”
“The aim of the study was to investigate the incidence and severity of stress urinary incontinence (SUI) in Etomoxir Metabolism inhibitor primigravid women at term and its association with maternal body weight.

This was an observational study of 458 primigravid women who came to give birth at Donostia Hospital during 2007. Urinary symptoms were investigated (2002 ICS definitions), and a physical examination including height, weight, pelvic floor muscle strength, and fetal presentation was performed. We calculated the incontinence severity index (ISI) and the women answered the International Consultation on Incontinence short form questionnaire.

SUI affected 139 (30.3%) primigravid women. The ISI distribution was 40.3% slight, 54.7% moderate, 4.3% severe, and 0.7% very severe. Pregnant women at term with body weight a parts per thousand yen75 kg appear to have more than doubled the risk of presenting SUI.

The incidence of SUI is high in pregnancy.

SETTING: Department of Ophthalmology, Gloucestershire Hospitals NHS Foundation Trust, Cheltenham, United Kingdom.

DESIGN: Database study.

METHODS: Hypothetical prediction errors were retrospectively calculated on prospectively collected data extracted from electronic medical records using manufacturers’ and optimized IOL constants with

Hoffer 3-Methyladenine price Q, Holladay 1, and SRK/T formulas for 2 IOLs. The acceptable IOL-constant optimization error margins, personalized IOL constants for individual surgeons, and minimum sample sizes for IOL-constant optimization were evaluated.

RESULTS: Optimization of IOL constants reduced the mean absolute errors from 0.66 diopters (D) and 0.52 D to 0.40 D and 0.42 D for the Sofport AO IOL and Akreos Fit IOL, respectively. The

percentage of eyes within +/- 0.25 D, +/- 0.50 D, and +/- 1.00 D of target refraction improved from for both IOL models. The IOL-constant errors exceeding 0.09 for the Hoffer Q, 0.09 for the Holladay 1, and 0.15 for the SRK/T produced inferior outcomes. Differences in personalized IOL constants between most surgeons were clinically insignificant. Calculating IOL constants to within 0.06, 0.06, and 0.10 for the Hoffer Q, Holladay 1, and SRK/T, respectively, required 148 to 257 eyes.

CONCLUSIONS: Optimizing IOL constants for IOLMaster biometry substantially improved refractive outcomes, far exceeding any additional benefit of personalizing IOL constants for individual surgeons.”
“2,7-di-tert-butylpyrene was oxidized to 2,7-di-tert-butylpyrene-4,5,9,10-tetraone. The latter through condensation reactions with vicinal C59 diamine such as 4,5-diaminophthalonitrile produced heterocyclic monomer, 2,7-di-tert-butyl pyrene[4,5][9,10]bisquinoxaline-6,7-dinitrile,

which was cyclo-tetramerized to the corresponding tetra[2,3-(1,4-diaza-6,6-di-tert-butylphenanthreno)[4,5]phthalocyanine]-based network polymer (2H-Pc), and tetra [2,3-(1,4-diaza-6,6-di-tert-butylphenanthreno)[4,5]phthalo-cyaninato metal II-based network polymers (M-Pc, M= Co, Ni, Zn, or Cu). Elemental analytical results, IR and NMR spectral data of the new prepared molecules are consistent with their assigned formulations. Molecular masses and metal contents Selleckchem ZD1839 of the synthesized polymers proved to be of high molecular masses which confirm the efficiency of tetramerization polymerization and complexation reactions. The dielectric constant (epsilon’) and dielectric loss tangent (tan delta) were studied as a function of temperature and frequency. The detailed analysis of the results showed that the dielectric dispersion consists of both dipolar and interfacial polarization. Measurements of ac conductivity as a function of frequency at different temperatures revealed that the nonoverlapping small polaron tunneling is the most suitable mechanism for ac conduction behavior. (C) 2011 Wiley Periodicals, Inc.