Enhancement of electrical conductivity associated with non-bridged oxygen defects in molybdenum phosphate oxide glass via doping of SrO.

Based on the attractive properties of phosphate glass, improved molybdenum phosphate glasses of composition 40P2O5, 20MoO3, 15MgO, (25-x)Li2O, xSrO, [x = 0, 5, 10, 15 and 20 mol %] were prepared via the melt-quench technique. They were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), UV-visible reflectance and Electron spin resonance (ESR). FTIR confirmed the existence of several structural phosphate groups other than MoO4 and MoO6 units. Optical analysis revealed the active species of molybdenum ions. SrO addition decreases the bandgap energy, converting the glass insulator features into semiconductor properties. The measured AC electrical conductivity (σac) increased within the temperature range of 298-473(K) and decreased in the frequency range of 0.042 kHz-1 MHz. The estimated DC electrical conductivity increased with temperature, suggesting the semiconducting behavior. The highest electrical conductivity was found in base and 5% SrO samples. Therefore, it appears that the prepared glasses are viable candidates for opto-electronic applications.

XRD, FTIR and ultrasonic investigations of cadmium lead bismuthate glasses.

Cadmium lead bismuthate glasses in the system xCdO-(1-x)[0.5PbO + 0.5Bi2O3](40 mol% ≤ x ≤ 90 mol%) were successfully prepared by melt-quenching method. The structural and elastic properties have been investigated using XRD, FTIR and ultrasonic pulse-echo techniques. The XRD patterns confirmed the amorphous nature of the samples prepared. Density and ultrasonic velocity data were used to evaluate various elastic properties. Addition of CdO gave rise to decreased density and molar volume and increased elastic moduli, micro-hardness, and Debye temperature. The FTIR analysis revealed that increasing CdO content enhances the BiO6 octahedral sites at the expense of the BiO3 and PbO4 units. This results in the formation of Pb-O-Bi(6) and Bi(3)-O-Bi(6) linkages in the glass network, which stiffen the structure and improve the elastic properties. A correlation between elastic and compositional parameters was achieved on the basis of theories and approaches in the field.

Airborne bacterial and PM characterization in intensive care units: correlations with physical control parameters.

In this study, the spatial variation of airborne bacteria in intensive care units (ICUs) was characterized. Fine particulate matter and several physical parameters were also monitored including temperature and relative humidity. The results showed that the total bacterial load ranged between 20.4 and 134.3 CFU/m3 across the ICUs. Bacterial cultures of the collected samples did not isolate any multi-drug-resistant Gram-negative bacilli indicating the absence of such aerosolized pathogens in the ICUs. Meanwhile, particulate matter levels in several ICUs were found to exceed the international guidelines set for 24-h PM exposure. Moreover, examining bacterial load contribution by size suggested that bacteria with sizes less than 0.65 µm contributed the least to the total bacterial loads, while those with sizes between 0.65 and 1.1 µm contributed the most. A multiple linear regression model was also built to predict the bacterial loads in the ICUs. The regression analysis explained 77% of the variability observed in the measured bacterial concentrations. The model showed that the level of activity in the ICU rooms as well as its occupancy level had strong positive correlations with bacterial loads, while distance away from the patient had a non-linear relationship with measured loads. No statistically significant correlation was found between bacterial load and particulate matter concentrations.

Crystallization effects on the photoluminescence efficiency of SrO-B2O3 glass activated by W6+, Eu3+, Dy3+ or Pr3+ ions.

Binary strontium borate host glass together with samples doped with 0.25 %WO3 and one of the rare - earth ions (0.125% Eu3+, Dy3+ or Pr3+) were prepared by conventional melting - annealing technique. DTA analysis of the host base glass was carried out to derive the proper temperatures which are necessary to convert glasses into their corresponding glass -ceramic through controlled thermal heat -treatment regime. Measurements of optical, FTIR, and PL spectra were carried out with special analysis of the spectral properties. The identity of glass - ceramic derivatives were investigated through x-ray diffraction, and TEM & SEM tools to identify their crystalline morphological features. The absorption spectrum of WO3 - doped glass refers to the existence of dominant hexavalent tungsten ions. The RE- doped glass reveal characteristic visible - NIR absorption peaks due to the respective rare earth ions. FTIR spectra show absorption bands due to both triangular and tetravalent borate groups (BO3, BO4).PL spectra reveal excitation and emission characteristic peaks due to each specific rare earth ions. XRD indicate the preference of the host glass to form strontium pyroborate (SrB4O7) crystalline phase. This facilitates the clear knowledge of the crystallization behavior and hence can justify the effect of the crystallization on the studied properties.

Sympatric occurrence of sibling Phytophthora species associated with foot rot disease of black pepper in India.

Foot rot disease caused by Phytophthora capsici is a serious threat to black pepper cultivation in India and globally. High diversity exists among the Phytophthora isolates of black pepper and hence detailed investigations of their morphology and phylogenetic taxonomy were carried out in the present study. In order to resolve the diversity, 182 isolates of Phytophthora, collected from different black pepper-growing tracts of South India during 1998-2013 and maintained in the National Repository of Phytophthora at ICAR-Indian Institute of Spices Research, Kozhikode, were subjected to morphological, molecular and phylogenetic characterization. Morphologically all the isolates were long pedicellate with umbellate/simple sympodial sporangiophores and papillate sporangia with l/b ranging from 1.63 to 2.55 µm. Maximum temperature for the growth was ~ 34 °C. Chlamydospores were observed in "tropicalis" group, whereas they were absent in "capsici" group. Initial molecular studies using internal transcribed spacer (ITS) marker gene showed two clear cut lineages-"capsici-like" and "tropicalis-like" groups among them. Representative isolates from each group were subjected to host differential test, multilocus sequence typing (MLST) and phylogeny studies. MLST analysis of seven nuclear genes (60S ribosomal protein L10, beta-tubulin, elongation factor 1 alpha, enolase, heat shock protein 90, 28S ribosomal DNA and TigA gene fusion protein) clearly delineated black pepper Phytophthora isolates into two distinct species-P. capsici and P. tropicalis. On comparing with type strains from ATCC, it was found that the type strains of P. capsici and P. tropicalis differed from black pepper isolates in their infectivity on black pepper. The high degree of genetic polymorphism observed in black pepper Phytophthora isolates is an indication of the selection pressure they are subjected to in the complex habitat which ultimately may lead to speciation. So based on the extensive analysis, it is unambiguously proved that the foot rot disease of black pepper in India is predominantly caused by two species of Phytophthora, viz. P. capsici and P. tropicalis. Presence of multiple species of Phytophthora in the black pepper agro-ecosystem warrants a revisit to the control strategy being adopted for managing this serious disease. The silent molecular evolution taking place in such an ecological niche needs to be critically studied for the sustainable management of foot rot disease.

Sonogashira diversification of unprotected halotryptophans, halotryptophan containing tripeptides; and generation of a new to nature bromo-natural product and its diversification in water.

The blending together of synthetic chemistry with natural product biosynthesis represents a potentially powerful approach to synthesis; to enable this, further synthetic tools and methodologies are needed. To this end, we have explored the first Sonogashira cross-coupling to halotryptophans in water. Broad reaction scope is demonstrated and we have explored the limits of the scope of the reaction. We have demonstrated this methodology to work excellently in the modification of model tripeptides. Furthermore, through precursor directed biosynthesis, we have generated for the first time a new to nature brominated natural product bromo-cystargamide, and demonstrated the applicability of our reaction conditions to modify this novel metabolite.

Natural products from myxobacteria: novel metabolites and bioactivities.

Covering: 2011-July 2016Myxobacteria are a rich source for structurally diverse secondary metabolites with intriguing biological activities. Here we report on new natural products that were isolated from myxobacteria in the period of 2011 to July 2016. Some examples of recent advances on modes-of-action are also summarised along with a more detailed overview on five compound classes currently assessed in preclinical studies.

Combination of vitamin E and clomiphene citrate in treating patients with idiopathic oligoasthenozoospermia: A prospective, randomized trial.

The most common cause of male infertility is idiopathic oligoasthenozoospermia. Empirical medical treatment for idiopathic male infertility is still a controversial issue. The aim of this study was to evaluate any possible effects of combining vitamin E as antioxidant and clomiphene citrate as antiestrogen on spermatozoa concentration and motility in comparison to give either of medications alone in patients with idiopathic oligoasthenozoospermia. This is a comparative prospective randomized study. Ninety patients with idiopathic oligoasthenozoospermia were randomized into equally three groups: Group A: received vitamin E (400 mg/day) for 6 months. Group B: received clomiphene citrate (25 mg daily) for 6 months. Group C: received combination of both drugs in the same doses for 6 months. All patients were subjected to the following: history taking, general and genital examination, semen analysis, serum FSH, total testosterone, and scrotal duplex. Semen examination was performed according to the guidelines of (WHO, 2010), at the start of treatment and was repeated after 3 months and after 6 months of treatment. Regarding vitamin E group, there was insignificant increase in mean sperm concentration after 6 months of treatment in comparison to baseline. On the other hand, there was a significant improvement of mean sperm concentration in the other two groups after 6 months of treatment, with more significance in combination therapy group (p = 0.001). The mean total sperm motility has improved in all patients groups, in comparison to baseline, with more significance in combination therapy group. In vitamin E group, it was 28.07 ± 9.65% (p = 0.000). For those in clomiphene citrate group, was 33.33 ± 14.10% (p = 0.003) and 40.50 ± 17.54% (p = 0.000) in combination therapy group. Combining antioxidant and anti-estrogen therapy is a valid option for the treatment of a selected group of men with unexplained isolated oligoasthenozoospermia.

Effect of extracorporeal shock wave lithotripsy on kidney growth in children.

PURPOSE: We investigated whether shock wave lithotripsy affects kidney growth in children. MATERIALS AND METHODS: This prospective controlled study included 150 children with renal stones who presented for shock wave lithotripsy between March 2005 and February 2010 (group A). The control arm included 100 children without any urological problems who were enrolled in the study after obtaining written maternal consent (group B). All children in both groups underwent abdominal ultrasound to assess renal size (bipolar renal length), which was repeated after 6 months for group A and after 1 year for both groups. RESULTS: Bipolar renal size in group A increased significantly at 6 months and 1 year after shock wave lithotripsy. Renal growth did not differ based on patient age at shock wave lithotripsy (p = 0.472), number of shock wave lithotripsy sessions (p = 0.65) or number of stones (p = 0.405). There was no significant difference between the rate of kidney growth in children who underwent shock wave lithotripsy during the year of the study and normal controls. CONCLUSIONS: Shock wave lithotripsy has no deleterious effect on the normal rate of renal growth in children. This outcome is not affected by either the number of stones or the age of the child at shock wave lithotripsy.

[Keratoconus screening in a Lebanese students' population]. / Dépistage du kératocône dans une population universitaire au Liban.

OBJECTIVE: Screening for keratoconus and potential risk factors in a medical student population in Lebanon using anterior topography. POPULATION AND METHODS: We randomly selected 110 medical students doing rotations in the Hôtel-Dieu de France hospital in Lebanon between November 2009 and February 2010. Ninety-two students agreed to participate in the screening protocol, which included a questionnaire and an anterior topography. The topography was performed using the placido disk Tomey(®) Topographic Modeling System TMS-4. The results were interpreted using the analysis programs supplied with the machine and by an experienced ophthalmologist. RESULTS: Ninety-two students participated in the study (83.6%): 49 males (53.2%) and 43 females (46.8%). The mean age was 23.6±1 year. Fifty-eight students were ametropic (63.1%): 44 participants were myopic (47.8%), 40 had astigmatism (43.4%), and six were hyperopic (6.5%). Three students (six eyes) were diagnosed with keratoconus. The prevalence of keratoconus was 3.3%, of which 2.2% were already known cases. The prevalence of forme frustre keratoconus was 1.1%. Eleven students (12.1%) had a family history of keratoconus, only one was diagnosed with the disease. Atopy and eye rubbing were not found significantly related to keratoconus in this population. CONCLUSION: Keratoconus is a prevalent disease among our population of Lebanese medical students, which confirms the clinical impression that keratoconus is relatively frequent in Lebanon. Further studies need to be conducted on a larger and more representative sample to assess keratoconus prevalence and risk factors in Lebanon.

Evaluation of renal function in children undergoing extracorporeal shock wave lithotripsy.

PURPOSE: The effect of extracorporeal shock wave lithotripsy on the growing kidneys of young children has always been a concern. We determined whether shock wave lithotripsy causes renal parenchymal scarring or affects glomerular filtration rate in children. MATERIALS AND METHODS: This prospective study included 100 children with renal stones who presented to the shock wave lithotripsy unit at our institution between March 2005 and March 2008. A total of 28 children had multiple stones in the same kidney. All children with bilateral renal stones had 1 kidney cleared of stones by percutaneous nephrolithotomy before undergoing shock wave lithotripsy. A total of 138 stones were subjected to shock wave lithotripsy. All children underwent radionuclide scan of the renal parenchyma using dimercapto-succinic acid, and glomerular filtration rate was estimated using diethylenetriamine pentaacetic acid before extracorporeal shock wave lithotripsy and 6 months afterward. Children with renal scarring due to previous surgery or vesicoureteral reflux were excluded from the study. The number of shock wave lithotripsy sessions to achieve stone-free status and the dose of shock waves used were recorded for each patient. RESULTS: No patient demonstrated renal parenchymal scarring on dimercapto-succinic acid scan or any statistically significant change in glomerular filtration rate on diethylenetriamine pentaacetic acid scan up to 6 months after shock wave lithotripsy. CONCLUSIONS: Shock wave lithotripsy is a safe modality for treating renal calculous disease in children up to 16 years old, with no impact on long-term kidney function.

Fungal peritonitis caused by Bipolaris spicifera.

An episode of fungal peritonitis was produced by Bipolaris spicifera in a 3-year-old girl with chronic renal failure secondary to uremic-hemolytic syndrome and who was under treatment with continuous ambulatory peritoneal dialysis (CAPD). Previously, an episode of purulent peritonitis caused by Pseudomonas spp. had been treated successfully with combined antibacterial therapy for 10 days. Microscopic and macroscopic examinations of the freshly collected purulent dialysate were negative for fungal structures and bacteria. The fungus grew from the dialysate plated on Sabouraud dextrose agar and was also macroscopically recognized as a colony attached to the inner wall of the Tenckhoff catheter. Specific cultures of dialysate for common bacteria and mycobacteria were negative. The patient was successfully treated with early catheter removal and empirical administration of 200 mg/day oral fluconazole for 2 weeks. Subsequently, a new catheter was placed and the patient continued well on CAPD. Post-treatment control cultures of dialysate for fungi, bacteria and mycobacteria were negative and the cell count returned to normal.

Confirmation of internal jugular guide wire position utilizing transesophageal echocardiography.

PURPOSE: To describe the utility of transesophageal echocardiography (TEE) in confirmation of correct central line J-wire position. CLINICAL FEATURES: A 51-yr-old male patient presented for urgent coronary artery bypass grafting. Current medications included aspirin, nitroglycerine, heparin and a B-blocker. Physical examination was unremarkable. Initial difficulty with right internal jugular vein cannulation was encountered. A posterior approach was used to access the vein with further difficulty in passing the J-wire. Simultaneous TEE images confirmed the correct J-wire position. CONCLUSION: The case demonstrates the value of TEE to confirm correct guide wire position prior to insertion of a large bore central venous catheter. TEE visualization of J-wire position avoided repeat attempts at internal jugular cannulation and potential carotid artery puncture.

Diaphragmatic rupture after epidural anaesthesia in a patient with diaphragmatic eventration.

An 85-year-old man with undiagnosed eventration of the left hemidiaphragm had an above-knee amputation under epidural anaesthesia. His post-operative course was stormy with two episodes of cardiovascular collapse. On the third post-operative day, rupture of the left hemidiaphragm was diagnosed, the bowel had herniated into the left hemithorax. It is proposed that the left hemidiaphragm ruptured spontaneously because of muscular weakness secondary to the thoracic segmental blockade associated with lumber epidural anaesthesia.

Susceptibility to hemolytic-uremic syndrome relates to erythrocyte glycosphingolipid patterns.

Hemolytic-uremic syndrome (HUS) is usually preceded by enteric infection by Shiga-like toxin-producing Escherichia coli (SLT-EC), but most children with SLT-EC diarrhea do not develop HUS. SLT toxicity depends on entry into the target cell via its host cell glycolipid receptor, globotriaosylceramide (Gb3). The relationship between differential susceptibility to HUS and erythrocyte Gb3 levels, as measured by high-pressure liquid chromatography, was studied. Erythrocytes of children with histories of HUS had lower nonhydroxylated fatty acyl (NFA) Gb3 levels than did erythrocytes of controls (1.6 vs. 2.0 nmol/mL of packed cells); these erythrocytes had lower ratios of NFA-Gb3 to lactosylceramide (0.16) than did erythrocytes of SLT-EC diarrheal patients without subsequent HUS (0.30; P < .003) or of healthy controls (0.28; P < .001). The lower erythrocyte Gb3 levels associated with HUS may reflect a genetic predisposition for differential outcomes of SLT-EC gastroenteritis.

Association between severity of gastrointestinal prodrome and long-term prognosis in classic hemolytic-uremic syndrome.

To determine whether severity of the prodromal gastrointestinal illness is associated with the course and complications of the extraintestinal manifestations of hemolytic-uremic syndrome, we conducted a retrospective review of children (n = 509) hospitalized with hemolytic-uremic syndrome. Those who came to the hospital with colitis and rectal prolapse associated with hemolytic-uremic syndrome (group I, n = 40) were compared with an equal number of time-matched children with hemolytic-uremic syndrome but without prolapse (group II). Children in group I had evidence of more severe colitis than children in group II had, as indicated by increased frequency of bloody diarrhea (p less than 0.001) and longer duration of diarrhea (p less than 0.001). However, they also had more severe extraintestinal manifestations during hemolytic-uremic syndrome, including edema (p less than 0.0001), severe thrombocytopenia (p less than 0.0001), prolonged anuria (p less than 0.001), and seizures (p = 0.036). Long-term prognosis for recovery of renal function was worse for group I than group II. Within group II, patients with bloody diarrhea had milder extraintestinal illness than those with prolapse but more severe extraintestinal illness than those with watery diarrhea. Analysis of Kaplan-Meier survival curves demonstrated a better prognosis for return of normal renal function in the children with watery diarrhea but without prolapse (p = 0.009) than in children with bloody diarrhea or prolapse. These data demonstrate that the severity of the gastrointestinal prodrome reflects the severity of the extraintestinal acute microangiopathic process and the resulting long-term outcome. Widespread vascular damage, often followed by permanent sequelae, is characteristic of patients with the most severe colitis.