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Polycrystalline Li0.5Ni0.25–0.5xCo0.5xZn0.5Fe2O4 ferrites (x = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5) were prepared by standard auto-combustion method and characterized by XRD and IR spectra. The XRD results suggest that all samples were single-phase with a cubic spinel-type structure. The lattice constant, particle size, metal-oxygen bond length (RA and RB), cation radii (rA and rB) on A and B-sub lattices were found to increase while the X-ray density and porosity, decrease with increasing x. The IR spectra show two absorption bands, at ν1 about 600 cm−1 and ν2 at about 425 cm−1, which were attributed to tetrahedral (A) and octahedral (B) sites of the spinel structure, respectively. The band positions were found to depend on x. The force constants, Kt and Ko, were calculated and plotted against cobalt concentration x. Compositional dependence of the force constants is explained in terms of cation-oxygen bond distances and redistribution of cations.

BACKGROUND: Preferred technique of anesthesia for caesarean section is spinal anesthesia and the commonest complication of this technique is hypotension. Because hypotension is associated with increased morbidity and mortality in the fetus as well as in the mother, several modalities have been recommended to bring down its incidence. Volume preloading 15-20min before spinal anesthesia is commonly practiced one. Among the different fluids available, commonly used for preloading are crystalloids and colloids. Many studies have been done to evaluate the efficacy of different fluids for preloading. Many investigators have found that colloids are superior to crystalloids for preloading. In this context, this study was designed to test the hypothesis that colloid preloading is associated with less hypotension than crystalloid preloading. AIM: To compare the efficacy of RL with Pentastarch 6% as preloading fluid in prevention of spinal induced hypotension in caesarean section patients. METHODOLOGY: Two groups, group I and group II comprising of 30 parturients each, belonging to ASA I and ASA II coming for elective caesarean section under spinal anesthesia were selected. Parturients in group I were preloaded with 1L of Ringer's lactate solution whereas those in group II were preloaded with 500 ml of Pentastarch 6% solution. After institution of spinal anesthesia with 2 ml-2.2ml of hyperbaric Bupivacaine using 25G Quincke's needle, patient's blood pressure and other vital parameters were monitored intraoperatively every 2 min for first 20 min and then every 5 min till the end of surgery and results were subjected to statistical analysis. RESULTS AND CONCLUSION: Parturients who were preloaded with Pentastarch 6% had less hypotension than those preloaded with RL. We concluded that colloids are better preloading agents than crystalloids for control of spinal induced hypotension in caesarean section patients.

BACKGROUND: The hypotension induced by spinal anesthesia in caesarean section patients can have deleterious effects on both mother and fetus. This can be prevented or minimized by various methods like trendelenburg position, left uterine displacement, prophylactic vasoconstrictor, volume preloading etc. Volume preloading is commonly practiced method. However, few recent studies have found lack of benefit by fluid preload. Hence this study. AIM: To assess efficacy of fluid preloading using RL in preventing spinal induced hypotension in caesarean section patients. METHODOLOGY: Two groups' control (C) group and study (S) group comprising of 30 parturients each, belonging to ASA I and ASA II coming for elective caesarean section under spinal anesthesia were selected. Parturients in control group received no fluid preload whereas those in study group were preloaded with 1L RL. After spinal anesthesia, patients' blood pressure and other vital parameters were monitored intraoperatively every 2 min for first 20 min and then every 5 min till the end of surgery. RESULTS AND CONCLUSION: Parturients who received RL preloading had lesser number of hypotensive episodes and lesser severe degree of hypotension than those without volume preload. Volume preloading has its own beneficial effects on incidence of spinal induced hypotension in parturients undergoing elective LSCS.

Bismuth strontium manganites Bi1 − xSrxMnO3 (0.20 ≤ x ≤ 0.50) belonging to the orthorhombic structural family were prepared in furnace using a solid-state reaction technique. Thick films of Bi(1 − x)SrxMnO3 were prepared by simple screen printing route. X-ray diffraction data suggest that the synthesized materials have an orthorhombic structure. For synthesized materials, texture coefficient (TC), dislocation density (ρD), density of crystallites per unit area (ψ), and mechanical properties are reported along with the influence of x on the structure and mechanical properties of BiMnO3 thick films.

NiFe2O4 nanopowder was synthesized by co-precipitation method. Precursors were mixed in a desired stoichiometric ratio and calcined at about 800°C to get nickel ferrite nanopowder. The synthesized nickel ferrite was characterized by XRD. The structural parameters such as the lattice constant (a), volume, average crystallite size (D), texture coefficient (TC) and lattice strain (η) have been determined.

The properties of nanocrystalline lead zirconate titanate [PZT, Pb(Zr0.52Ti0.48)O3] thick films and pellets synthesized by self-propagating auto combustion route using sucrose as a fuel are reported. The X-ray diffraction reveals the formation of nanocrystalline tetragonal PZT having a particle size of 5.52 nm in thick films and 7.08 nm in bulk material. SEM images show the grain size of 300–400 nm with some agglomeration, as well as modified open grain boundaries and grain growth in the PZT thick film as compared to the bulk material. The DC electric resistivity of PZT shows semiconducting behavior. We also characterized the 8–18 GHz microwave insertion loss, absorption, complex permittivity, and microwave conductivity of synthesized materials. The real part of permittivity and dielectric loss were found to decrease with increasing frequency.

Introduction: Diabetic peripheral neuropathic pain (DPNP) is a debilitating and distressing complication that occurs in patients with diabetes mellitus. This article provides an overview of diabetic peripheral neuropathy focusing on DPNP. Areas covered: This article reviews the diagnosis, pathogenesis, prevention and treatment of diabetic neuropathy and neuropathic pain. A comprehensive and systematic Medline search of the published literature for treatment of diabetic peripheral neuropathy was done from 1965 to December 2012. Studies not in English language were excluded. Expert opinion: Neuropathic pain is difficult to treat, and patients rarely experience complete pain relief. Despite several pharmacological agents being used in the treatment of DPNP, only duloxetine and pregabalin have evidence-based support for controlling DPNP.

Bismuth strontium manganites (BSM) with variation in strontium content have been synthesized by simple solid state reaction method. X-ray diffraction data show that the samples have orthorhombic structure with crystallite size ∼40 to 60 nm. SEM studies reveal morphology of micro-rods and micro-flakes. The dielectric constant (ɛ′) and the dielectric loss (tan δ) decreases with the strontium content and the applied frequency which has been attributed to Maxwell-Wagner polarization. The microwave conductivity of samples decreases from 8.9 S/cm to 2.29 S/cm at 8.2 GHz as strontium increases. The penetration depth has also been reported at microwave frequencies from 8–18 GHz.

This report presents the synthesis of cadmium ferrite (CdFe2O4) by Oxalate co-precipitation and its subsequent characterization by using X-ray diffraction (XRD) and Fourier transform Infrared spectroscopy (FTIR) techniques. XRD results confirm the single cubic spinel phase formation with lattice parameter 8.7561Ao. An infrared spectroscopy study shows the presence of main two absorption bands indicating the presence of tetrahedral and octahedral group complexes, respectively, within the spinel lattice. We also report strain, hopping length (LA and LB) and dislocation density of ferrite sample.

Because few randomized trials have been done, little is known about appropriate glycemic control in hospitalized patients with chronic kidney disease (CKD) and diabetes mellitus. These patients are at high risk of hypoglycemia. It is prudent to monitor glucose closely, set less-stringent blood sugar goals, avoid oral antidiabetic agents, and possibly reduce insulin dosage.

The influence of the Fe on the microstructure, electrical and dielectric properties of Ni 0.6 Cu 0.4 Fe y Mn 2− y O 4 (0.1 ≤ y ≤ 0.5) negative temperature coefficient (NTC) thermistors prepared by well known simple chemical co-precipitation method were studied. The replacement of manganese by iron plays an important role in changing the lattice parameter, X-ray density, sintered density, porosity, DC resistivity at different temperatures and dielectric properties at different frequencies. The X-ray and sintered density increased linearly and porosity decreased with iron. The room temperature resistivity of nickel copper manganite NTC ceramic decreased from 1 MΩ cm to 68 KΩ cm and dielectric constant increased from ∼9 × 10 7 to 1.5 × 10 9 at 20 Hz as iron content increased.

Female age influence on mating success, courtship activities, mating latency, copulation duration, fecundity, ovarioles number, and wing length has been studied using isofemale lines of Drosophila bipectinata collected at three different localities. It was observed that in all localities, middle-aged D. bipectinata females had significantly greater mating success, showed less rejection responses to courting male, mated faster, copulated longer, and had greater fecundity and ovariole number than young and old-aged females. Further, old-aged females had comparatively less fitness traits than young age females. This research suggests the occurrence of age specific female reproductive success as follows: middle-aged > young > old-aged.

Oral thin films of 6-mercaptopurine were fabricated from mucoadhesive polymer, chitosan and polyvinylpyrrolidone for the purpose of prolonging drug release and improving its bioavailability. All fabricated film formulations prepared were smooth and translucent, with good flexibility. The weight and thickness of all the formulations were found to be uniform. These films were also evaluated for surface pH, folding endurance, swelling percentage (% S) and in vitro disintegration time. Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) were used to evaluate the physico-chemical nature of the films. In-vitro drug release have shown enhanced release profiles for thin films compared to pure drug and the release patterns have been found to be pH dependant. The results of the study reveals that fabrication of 6-MP oral thin film by using solvent cast technology is a simple and an efficient method for drug delivery to achieve desired therapeutic compliance.Keywords: 6-mercaptopurine; In Vitro Drug Release; SEM; FTIR

Abstract —We exposed 63 adult spontaneously hypertensive rats (SHR) and 10 (mRen-2)27 transgenic hypertensive rats to a 12-day regimen of either a normal diet (0.5%) or a low-salt diet (0.05%) to evaluate the hypothesis that the vasodepressor heptapeptide, angiotensin-(1–7) [Ang-(1–7)], buffers the pressor effects of angiotensin II during endogenous stimulation of the renin-angiotensin system. Catheters were inserted into a carotid artery and jugular vein under light anesthesia the day before the experiment. Separate groups of conscious instrumented SHR were given short-term infusions of an affinity-purified monoclonal Ang-(1–7) antibody or the neprilysin inhibitor SCH 39370. In addition, SHR and (mRen-2)27 rats were given the Ang-(1–7) receptor antagonist [ d -Ala 7 ]Ang-(1–7). Exposure to the low-salt diet increased plasma renin activity and elevated plasma levels of angiotensin I and angiotensin II in SHR by 81% and 68%, respectively, above values determined in SHR fed a normal salt diet. Concentrations of angiotensin I and angiotensin II were also higher in the kidney of salt-depleted SHR, whereas plasma and renal tissue levels of Ang-(1–7) were unchanged. Infusion of the Ang-(1–7) antibody produced dose-dependent pressor and tachycardic responses in salt-depleted SHR but no effect in SHR maintained on a normal-salt diet. A comparable cardiovascular response was produced in salt-depleted SHR given either SCH 39370 or [ d -Ala 7 ]Ang-(1–7). These agents had negligible effects on SHR fed a normal-salt diet. Blockade of Ang-(1–7) receptors produced a similar cardiovascular response in (mRen-2)27 transgenic hypertensive rats fed a low-salt diet. Injections of the heat-inactivated antibody or the subsequent infusion of the antibody to rats given [ d -Ala 7 ]Ang-(1–7) produced no additional effects. The data support the hypothesis that the hemodynamic effects of neurohormonal activation after salt restriction stimulate a tonic depressor action of Ang-(1–7).

Prostaglandins are known to participate in the antihypertensive actions of angiotensin-converting enzyme (ACE) inhibition and angiotensin type 1 (AT1)-receptor antagonism. Because angiotensin-(1-7) [Ang-(1-7)] is markedly elevated after prolonged ACE-inhibitor treatment, we determined whether the antihypertensive effects of Ang-(1-7) were mediated by release of prostaglandins. Male spontaneously hypertensive rats (SHRs, 10 weeks) were treated for 9 days with either lisinopril (20 mg/kg) or losartan (10 mg/kg) or a combination of both drugs. Rats were implanted with catheters in the carotid artery and jugular vein to record blood pressure and to infuse drug solutions, respectively. Neutralization of circulating Ang-(1-7) by monoclonal antibody resulted in a dose-dependent increase in blood pressure in SHRs treated with either lisinopril or losartan. Administration of CGS 24592 to block Ang-(1-7) formation also resulted in an increase in blood pressure that was comparable to antibody infusion. However, Ang-(1-7) blockade evoked a greater elevation in blood pressure in the lisinopril and lisinopril/losartan-treated rats in comparison to those treated with losartan alone. Acute treatment with the cyclooxygenase (COX) inhibitor indomethacin increased blood pressure to a similar extent to that of CGS 24592, as well as blocked the increase in pressure with the neprilysin inhibitor in the lisinopril/losartan group. In the losartan-treated animals, however, indomethacin increased blood pressure by a larger extent than that of the Ang-(1-7) antibody or CGS 24592, and CGS 24592 did not abolish the subsequent pressor response to indomethacin in these animals. In contrast to the antibody or neprilysin inhibitor, administration of the Ang-(1-7) antagonist D-[Ala7]-Ang-(1-7) increased blood pressure to a similar extent in lisinopril or losartan treatments. Moreover, D-[Ala7]-Ang-(1-7) increased blood pressure to a comparable extent as indomethacin and blocked any further increase with the COX inhibitor in the losartan-treated SHRs. High-resolution emulsion autoradiography revealed 125I-[Sarcosine1, Threonine8]-Ang II (Sarthran) binding in the mesenteric artery and thoracic aorta in the presence of both LOS and the AT2 antagonist PD123319. The non-AT1/non-AT2 Sarthran binding was displaced by Ang-(1-7), DALA, or Ang II. These studies suggest that vasodilatory eicosanoids mediate the antihypertensive effects of endogenous Ang-(1-7) in both LIS and LIS/LOS therapies. Furthermore, in the presence of AT1-receptor blockade, Ang II may interact with a DALA-sensitive site to promote eicosanoid release.

Abstract —We determined the mechanism accounting for the removal and metabolism of angiotensin-(1–7) [Ang-(1–7)] in 21 anesthetized spontaneously hypertensive (SHR), 18 age-matched normotensive Sprague-Dawley (SD), and 36 mRen-2 transgenic (TG + ) rats. Animals of all 3 strains were provided with tap water or tap water containing losartan, lisinopril, or a combination of lisinopril and losartan for 2 weeks. On the day of the experiment, Ang-(1–7) was infused for a period of 15 minutes at a rate of 278 nmol · kg −1 · min −1 . After this time, samples of arterial blood were collected rapidly at regular intervals for the assay of plasma Ang-(1–7) levels by radioimmunoassay. Infusion of Ang-(1–7) had a minimal effect on vehicle-treated SD rats but elicited a biphasic pressor/depressor response in vehicle-treated SHR and TG + rats. In lisinopril-treated rats, Ang-(1–7) infusion increased blood pressure, whereas losartan treatment abolished the pressor component of the response without altering the secondary fall in arterial pressure. Combined treatment with lisinopril and losartan abolished the cardiovascular response to Ang-(1–7) in all 3 strains. In vehicle-treated SD, SHR and TG + the half-life (t 1/2 ) of Ang-(1–7) averaged 10±1, 10±1, and 9±1 seconds, respectively. Lisinopril alone or in combination with losartan produced a statistically significant rise in the half-life of Ang-(1–7) in all 3 strains of rats. Plasma clearance of Ang-(1–7) was significantly greater in the untreated SD rats compared with either the SHR or TG + rat. Lisinopril treatment was associated with reduced clearance of Ang-(1–7) in all 3 strains. Concurrent experiments in pulmonary membranes from SD and SHR showed a statistically significant inhibition of 125 I-Ang-(1–7) metabolism in the presence of lisinopril. These studies showed for the first time that the very short half-life of Ang-(1–7) in the circulation is primarily accounted for peptide metabolism by ACE. These findings suggest a novel role of ACE in the regulation of the production and metabolism of the two primary active hormones of the renin angiotensin system.

This study assessed the role of angiotensin (Ang) AT 1 and AT 2 receptors as modulators of the plasma clearance of Ang II. Groups of male spontaneously hypertensive rats (SHRs; n = 25) were given an intravenous injection of either saline, losartan, PD123319, losartan in combination with PD123319, or Sar 1 -Thr 8 -Ang II. One hour later, Ang 11 (0.5 μg/kg) was infused for 15 min into a vein. Immediately thereafter, arterial blood samples were collected at regular intervals for the assay of plasma Ang II levels by radioimmunoassay. The infusion of Ang II significantly increased baseline mean arterial pressure (MAP) in rats pretreated with either saline or PD123319 but not in those receiving losartan, losartan combined with PD123319, or Sar 1 -Thr 8 -Ang II. The plasma clearance of Ang II was significantly greater in rats injected with either PD123319, losartan combined with PD123319, or Sar 1 -Thr 8 -Ang II compared to those injected either saline or losartan. Furthermore, the half-life of Ang II in rats pretreated with saline or losartan was significantly greater than that measured in the other three groups. These results suggest that plasma clearance of Ang II in the SHRs is independent of an AT 1 receptor, but plasma levels of the peptide are unexpectedly protected by an AT 2 receptor-dependent mechanism.

Angiotensin-converting enzyme (ACE) inhibition alone or in combination with the angiotensin type-I receptor (AT 1 ) antagonist losartan augments circulating levels of the bioactive peptide angiotensin-(1–7) [Ang-(1–7)]. Hence, we determined whether Ang-(1–7) contributes to the hypotensive effects produced by the combined administration of lisinopril and losartan in spontaneously hypertensive rats by blocking the peptide’s synthesis with either of two structurally different neprilysin inhibitors. Intravenous administration of CGS 24592 (30 mg/kg) to rats in which blood pressure was normalized by 9 days of therapy with lisinopril and losartan elicited an elevation of mean arterial pressure that was sustained throughout the infusion period and for 20 minutes thereafter. The hypertensive response was associated with a 62% reduction in circulating levels of Ang-(1–7) and no change in plasma angiotensin II (Ang II). Intravenous infusion of one other neprilysin inhibitor (SCH 39370, 30 mg/kg) produced an increase in mean blood pressure of a magnitude similar to that found with CGS 24592. Pretreatment with the nonselective antagonist [Sar, 1 Thr 8 ]-Ang II abolished any additional pressor effects of either neprilysin inhibitor in spontaneously hypertensive rats treated with lisinopril or losartan. However, neither the endothelin A antagonist BQ123 nor the kinin B2 antagonist HOE 140 had an effect on basal blood pressure or altered the pressor or heart rate effects of the neprilysin inhibitors. These data suggest that inhibition of Ang-(1–7) formation in rats exposed to the combined blockade of Ang II production and activity is associated with a reversal of the antihypertensive actions produced by these therapies. Thus, endogenous Ang-(1–7) functions as a vasodilator hormone in this form of genetic hypertension.

Drosophila (L.) (Diptera: Drosophilidae) has richly contributed to the understanding of patterns of inheritance, variation, speciation, and evolution. Drosophila, with its cosmopolitan nature and complexities in species compositions, is an excellent model for studying the eco-distributional patterns of various species. This study analyzed the altitudinal and seasonal variation in Drosophila species of Mount Japfu in Nagaland, a sub-Himalayan hilly state of northeast India, over the course of one year. A total of 4,680 Drosophila flies belonging to 19 species of 4 subgenera were collected at altitudes of 1500, 1800, 2100, 2400, and 2700 m a.s.l. The subgenus Sophophora Sturtevant was predominant, with 10 species, followed by subgenus Drosophila, with 4 species. Subgenus Dorsilopha and subgenus Scaptodrosophila were represented by 1 species each. The remaining 3 species were not identified. Cluster analysis and constancy methods were used to analyze the species occurrence qualitatively. Altitudinal changes in the population densities and relative abundances of the different species at different seasons were also studied. The diversity of the Drosophila community was assessed by applying Simpson's diversity index. At 1800 m a.s.l., the Simpson's index was low (0.09301), suggesting high Drosophila diversity at this altitude. The density of Drosophila changed significantly during different seasons (F = 26.72; df = 2; p < 0.0001). The results suggest the distributional pattern of a species or related group of species was uneven in space and time.

Chronic fructose treatment in rats repeatedly has been shown to elevate blood pressure associated with insulin resistance and hyperinsulinemia. Activation of the sympathetic nervous system and the renin-angiotensin system, vascular hypertrophy, and sodium retention by the kidney tubules have been proposed to be some of the mechanisms by which insulin elevates blood pressure. The precise mechanism by which hypertension develops in fructose fed rats is still not known. The purpose of the current study was twofold. The first objective was to assess the effect of a fructose-enriched diet on urinary sodium excretion. The second objective was to investigate any changes in plasma volume and extracellular volume in fructose-fed rats. In both experiments, male Sprague-Dawley rats were divided into equal groups. Rats in the control group were fed Purina Laboratory Chow, whereas those in the experimental group were fed a 60% fructose diet. There was a significant elevation in the blood pressure of fructose-fed rats at the end of the second week of treatment, and it remained elevated for the remainder of the dietary intervention. In the first experiment, there was no significant difference in sodium, potassium or urine excretion throughout the 6 weeks of dietary treatment. At the end of this study, the serum insulin levels of fructose-fed rats were significantly greater than the levels in the control group. In the second experiment, which was a 4-week study, there was no significant difference in hematocrit, plasma volume, or extracellular fluid volume between control and fructose-fed animals at 2 or 4 weeks of dietary treatment. The results of these two in vivo studies are the first to document that elevation of blood pressure in fructose-fed rats does not occur directly via sodium retention or an increase in fluid volume.