Transfer of 45Ca and 36Cl at the blood-nerve barrier of the sciatic nerve in rats fed low or high calcium diets

Unidirectional fluxes of 45Ca, 36Cl, and of [3H]mannitol from blood into the sciatic nerve and cerebral cortex were determined from 5- and 15-min uptakes of these tracers after an intravenous (i.v.) bolus injection in awake rats. Rats were fed diets for 8 wk, that had either a low (0.01% wt/wt), normal (0.67%), or high (3%) Ca content. Plasma [Ca] was 32% less and 11% more in rats fed low (LOCA) and high Ca diets (HICA), respectively, than in rats fed a normal Ca diet (CONT). The mean permeability-surface area product (PA) of 45Ca at the blood-nerve barrier was about eightfold higher than at the blood-brain barrier in the same animals and did not differ significantly between groups (greater than 0.05). Mean PA ratios of 45Ca/36Cl for the blood-nerve and blood-brain barriers in CONT rats, 0.52 +/- 0.04 and 0.40 +/- 0.02, respectively, were not significantly different from corresponding ratios in LOCA and HICA groups, and corresponded to the aqueous limiting diffusion ratio (0.45). Our results show no evidence for concentration-dependent transport of Ca over a plasma [Ca] range of 0.8-1.4 mmol/liter at the blood-nerve barrier of the rat peripheral nerve, and suggest that Ca and Cl exchange slowly between nerve and blood via paracellular pathways.     

Optimum excitation of phases and amplitudes in a phased array hyperthermia system.

In order to achieve a desired temperature distribution inside and outside of malignant tissues, optimization techniques could be used in phased array hyperthermia systems to control effectively the amplitude and phase of the radiating elements. The optimization of a four-element phased array hyperthermia system operating at 432 MHz is examined theoretically. The proposed technique is based on a detailed physical model of the tissue medium to be heated in terms of both electromagnetic and thermal properties. A penalty function technique using a Newton method is applied to determine the optimum phases and amplitudes of the array. Several array geometries have been studied and numerical results are presented.     

Psychopathology Symptoms are Associated with Prenatal Health Practices in Pregnant Women with Heavy Smoking Levels

Purpose

Smoking during pregnancy may be linked to other problematic prenatal health behaviors in women. We examined interrelationships among prenatal smoking, prenatal health behaviors and mental health. The objective of this study was to examine factors that may contribute to variations in prenatal health practices among women who smoke during pregnancy.

Methods

Birth mothers from an adoption study (N?=?912) were interviewed about prenatal smoking, health behaviors, and mental health symptoms at 5 months postpartum.

Results

One-quarter of participants (N?=?222) reported smoking 6 or more cigarettes daily for at least 1 trimester. For mothers who smoked more than 6 cigarettes daily, higher levels of antisocial behaviors (β?=????.14, p?=?.03) and depressive symptoms (β?=????.17, p?=?.03) were associated with less frequent prenatal folate use; antisocial behaviors and depressive symptoms were not associated for prenatal folate use among women who did not smoke more than 6 cigarettes daily. For mothers who did not smoke more than 6 cigarettes daily, more depressive symptoms were associated with fewer prenatal care visits (β?=?.12, p?=?.01). Antisocial behaviors and anxiety symptoms were not associated with prenatal care visits in either group of mothers.

Conclusions for Practice

Maternal antisocial behaviors and depressive symptoms during pregnancy may be markers for poorer adherence to recommendations for folate supplementation among women who smoke 6 or more cigarettes daily during pregnancy, independent of adequacy of prenatal care.

     

Novel second-generation rexinoid induces growth arrest and reduces cancer cell stemness in human neuroblastoma patient-derived xenografts

IntroductionThe poor therapeutic efficacy seen with current treatments for neuroblastoma may be attributed to stem cell-like cancer cells (SCLCCs), a subpopulation of cancer cells associated with poor prognosis and disease recurrence. Retinoic acid (RA) is a differentiating agent used as maintenance therapy for high-risk neuroblastoma but nearly half of children treated with RA relapse. We hypothesized that 6-Methyl-UAB30 (6-Me), a second-generation rexinoid recently developed with a favorable toxicity profile compared to RA, would reduce cancer cell stemness in human neuroblastoma patient-derived xenografts (PDXs).MethodsCells from three neuroblastoma PDXs were treated with 6-Me and proliferation, viability, motility, and cell-cycle progression were assessed. CD133 expression, sphere formation, and mRNA abundance of stemness and differentiation markers were evaluated using flow cytometry, in vitro extreme limiting dilution analysis, and real-time PCR, respectively.ResultsTreatment with 6-Me decreased proliferation, viability, and motility, and induced cell-cycle arrest and differentiation in all three neuroblastoma PDXs. In addition, 6-Me treatment led to decreased CD133 expression, decreased sphere-forming ability, and decreased mRNA abundance of Oct4, Nanog, and Sox2, indicating decreased cancer cell stemness.Conclusions6-Me decreased oncogenicity and reduced cancer cell stemness of neuroblastoma PDXs, warranting further exploration of 6-Me as potential novel therapy for neuroblastoma.     

Iris vasculopathy in galactose-fed rats

Increased iris vessel permeability observed in diabetics has also been reported to occur in diabetic animals and galactose-fed rats. The potential role of aldose reductase in the induction of iris vessel changes has been investigated in rats fed a 50% galactose diet with/without the aldose reductase inhibitors AL 1576, sorbinil or ponalrestat for 7 to 18 months. Compared to normal control rats, long-term galactose-fed rats display a breakdown of the blood-aqueous barrier due to iris vessel changes that include focal straightening, dilation, constriction, increased permeability, ischemia and new vessel proliferation. The onset and progression of these iridal vessel changes were prevented by the aldose reductase inhibitors AL 1576 and sorbinil, and reduced by Ponalrestat. Computerized analyses of lumen areas of iris vessels indicated an 18-fold decrease in the vascular area near the pupillary boarder in untreated galactose-fed rats compared with age-matched controls and galactose-fed rats treated with aldose reductase inhibitors. These observations linking iris vessel changes with galactose-feeding, coupled with the fact that aldose reductase inhibitors also prevent these changes, strongly suggest a link between the sorbitol pathway and the appearance and progression of iris vessel changes.     

Hardening of Additive Manufactured 316L Stainless Steel by Using Bimodal Powder Containing Nanoscale Fraction

The particle size distribution significantly affects the material properties of the additively manufactured parts. In this work, the influence of bimodal powder containing nano- and micro-scale particles on microstructure and materials properties is studied. Moreover, to study the effect of the protective atmosphere, the test samples were additively manufactured from 316L stainless steel powder in argon and nitrogen. The samples fabricated from the bimodal powder demonstrate a finer subgrain structure, regardless of protective atmospheres and an increase in the Vickers microhardness, which is in accordance with the Hall-Petch relation. The porosity analysis revealed the deterioration in the quality of as-built parts due to the poor powder flowability. The surface roughness of fabricated samples was the same regardless of the powder feedstock materials used and protective atmospheres. The results suggest that the improvement of mechanical properties is achieved by adding a nano-dispersed fraction, which dramatically increases the total surface area, thereby contributing to the nitrogen absorption by the material.     

Sustainable extraction of pesticides in food and environmental samples using emerging green adsorbents

There are many emerging adsorbents, with relatively high adsorption capacities, that can be used during the extraction of pesticides from complex matrices. Poly(ionic liquids) are among these emerging adsorbents. The applications of poly(ionic liquids) as adsorbents during pesticide pre-concentration are explored in this paper. Some researchers have taken advantage of the adhesive nature of polydopamine and used it to synthesise adsorbents with relatively high adsorption capacities. The use of polydopamine-based sorbents during pesticide pre-concentration is also reviewed in this paper. Deep eutectic solvents, on the other hand, can be used to synthesise adsorbents to extract pesticides in complex matrices. This is usually done either by immobilising it on a solid support or by polymerisation. Applications of deep eutectic solvent-based adsorbents during pesticide extraction are discussed in detail in this review. In addition, this review has explored the challenges associated with the use of these emerging adsorbents during the extraction of pesticides as well as the future prospects.     

Molecular characterization of the transition to mid-life in Caenorhabditis elegans

We present an initial molecular characterization of a morphological transition between two early aging states. In previous work, an age score reflecting physiological age was developed using a machine classifier trained on images of worm populations at fixed chronological ages throughout their lifespan. The distribution of age scores identified three stable post-developmental states and transitions. The first transition occurs at day 5 post-hatching, where a significant percentage of the population exists in both state I and state II. The temperature dependence of the timing of this transition (Q ₁₀?~?1.17) is too low to be explained by a stepwise process with an enzymatic or chemical rate-limiting step, potentially implicating a more complex mechanism. Individual animals at day 5 were sorted into state I and state II groups using the machine classifier and analyzed by microarray expression profiling. Despite being isogenic, grown for the same amount of time, and indistinguishable by eye, these two morphological states were confirmed to be molecularly distinct by hierarchical clustering and principal component analysis of the microarray results. These molecular differences suggest that pharynx morphology reflects the aging state of the whole organism. Our expression profiling yielded a gene set that showed significant overlap with those from three previous age-related studies and identified several genes not previously implicated in aging. A highly represented group of genes unique to this study is involved in targeted ubiquitin-mediated proteolysis, including Skp1-related (SKR), F-box-containing, and BTB motif adaptors.