Flexible InGaN nanowire membranes for enhanced solar water splitting.

III-Nitride nanowires (NWs) have recently emerged as potential photoelectrodes for efficient solar hydrogen generation. While InGaN NWs epitaxy over silicon is required for high crystalline quality and economic production, it leads to the formation of the notorious silicon nitride insulating interface as well as low electrical conductivity which both impede excess charge carrier dynamics and overall device performance. We tackle this issue by developing, for the first time, a substrate-free InGaN NWs membrane photoanodes, through liftoff and transfer techniques, where excess charge carriers are efficiently extracted from the InGaN NWs through a proper ohmic contact formed with a high electrical conductivity metal stack membrane. As a result, compared to conventional InGaN NWs on silicon, the fabricated free-standing flexible membranes showed a 10-fold increase in the generated photocurrent as well as a 0.8 V cathodic shift in the onset potential. Through electrochemical impedance spectroscopy, accompanied with TEM-based analysis, we further demonstrated the detailed enhancement within excess charge carrier dynamics of the photoanode membranes. This novel configuration in photoelectrodes demonstrates a novel pathway for enhancing the performance of III-nitrides photoelectrodes to accelerate their commercialization for solar water splitting.

Nanomembrane-Based, Thermal-Transport Biosensor for Living Cells.

Knowledge of materials' thermal-transport properties, conductivity and diffusivity, is crucial for several applications within areas of biology, material science and engineering. Specifically, a microsized, flexible, biologically integrated thermal transport sensor is beneficial to a plethora of applications, ranging across plants physiological ecology and thermal imaging and treatment of cancerous cells, to thermal dissipation in flexible semiconductors and thermoelectrics. Living cells pose extra challenges, due to their small volumes and irregular curvilinear shapes. Here a novel approach of simultaneously measuring thermal conductivity and diffusivity of different materials and its applicability to single cells is demonstrated. This technique is based on increasing phonon-boundary-scattering rate in nanomembranes, having extremely low flexural rigidities, to induce a considerable spectral dependence of the bandgap-emission over excitation-laser intensity. It is demonstrated that once in contact with organic or inorganic materials, the nanomembranes' emission spectrally shift based on the material's thermal diffusivity and conductivity. This NM-based technique is further applied to differentiate between different types and subtypes of cancer cells, based on their thermal-transport properties. It is anticipated that this novel technique to enable an efficient single-cell thermal targeting, allow better modeling of cellular thermal distribution and enable novel diagnostic techniques based on variations of single-cell thermal-transport properties.

Simple statistical channel model for weak temperature-induced turbulence in underwater wireless optical communication systems.

In this Letter, we use laser beam intensity fluctuation measurements to model and describe the statistical properties of weak temperature-induced turbulence in underwater wireless optical communication (UWOC) channels. UWOC channels with temperature gradients are modeled by the generalized gamma distribution (GGD) with an excellent goodness of fit to the measured data under all channel conditions. Meanwhile, thermally uniform channels are perfectly described by the simple gamma distribution which is a special case of GGD. To the best of our knowledge, this is the first model that comprehensively describes both thermally uniform and gradient-based UWOC channels.

Droop-Free, Reliable, and High-Power InGaN/GaN Nanowire Light-Emitting Diodes for Monolithic Metal-Optoelectronics.

A droop-free nitride light-emitting diode (LED) with the capacity to operate beyond the "green gap" has been a subject of intense scientific and engineering interest. While several properties of nanowires on silicon make them promising for use in LED development, the high aspect ratio of individual nanowires and their laterally discontinuous features limit phonon transport and device performance. Here, we report on the monolithic integration of metal heat-sink and droop-free InGaN/GaN quantum-disks-in-nanowire LEDs emitting at ∼710 nm. The reliable operation of our uncooled nanowire-LEDs (NW-LEDs) epitaxially grown on molybdenum was evident in the constant-current soft burn-in performed on a 380 µm × 380 µm LED. The square LED sustained 600 mA electrical stress over an 8 h period, providing stable light output at maturity without catastrophic failure. The absence of carrier and phonon transport barriers in NW-LEDs was further inferred from current-dependent Raman measurements (up to 700 mA), which revealed the low self-heating. The radiative recombination rates of NW-LEDs between room temperature and 40 °C was not limited by Shockley-Read-Hall recombination, Auger recombination, or carrier leakage mechanisms, thus realizing droop-free operation. The discovery of reliable, droop-free devices constitutes significant progress toward the development of nanowires for practical applications. Our monolithic approach realized a high-performance device that will revolutionize the way high power, low-junction-temperature LED lamps are manufactured for solid-state lighting and for applications in high-temperature harsh environment.

Altered expression of chemokines and their receptors at porcine maternal-fetal interface during early and mid-gestational fetal loss.

Chemokines play a significant role in pregnancy, especially during embryonic attachment and placental development. During early pregnancy, immune cells are recruited extensively to the endometrium in several species including pigs. However, this recruitment is solely mediated by the presence of the conceptus in pigs making it a unique feature compared with other species (humans, primates and mice). To understand the biological significance of chemokine expression and immune cell recruitment in the context of fetal loss, we investigate a well-characterized porcine fetal loss model during the window of early pregnancy at gestational day (gd) 20 and mid-pregnancy (gd50). These periods coincide with 25-40 % of conceptus loss. Using targeted quantitative polymerase chain reaction and Western blot approaches, we screened a specific set of chemokines. Comparisons were made with endometrial lymphocytes (ENDO LY), endometrium and chorioallantoic membranes (CAM) associated with spontaneously arresting and healthy conceptus attachment sites (CAS). mRNA expression studies revealed an increased expression of CXCR3 and CCR5 in ENDO LY and of CXCL10, CXCR3, CCL5 and CCR5 in the endometrium associated with arresting CAS at gd20. DARC was decreased in the endometrium at gd50. CCL1 was increased in CAM associated with arresting CAS at gd50. Some of these differences were also noted at the protein level (CXCL10, CXCR3, CCL5 and CCR5) in the endometrium and CAM. CD45+ immunohistochemistry demonstrated a significantly higher localization in ENDO LY in the endometrium associated with healthy versus arresting counterparts. Most of these differences were observed in early pregnancy and might contribute towards a shift in immune cell functions.

Expression of leptin and its long form receptor at the porcine maternal-fetal interface: contrasting healthy and arresting conceptus attachment sites during early and mid-pregnancy.

BACKGROUND: It is well established that spontaneous conceptus loss in swine is associated with an imbalance of both angiogenic and immunological factors. Leptin (LEP), a metabolic hormone, has also been implicated in the promotion of angiogenesis. In this study, LEP and its long form receptor (OB-Rb) were evaluated during porcine pregnancy to assess their basal level of expression and their potential role in conceptus development. METHODS: Expression and secretion of LEP and OB-Rb were quantified in the endometrium of non-pregnant (n = 5), and in the endometrium and chorioallantoic membrane (CAM) of pregnant sows (parity 2 to 5) at gestational days (gd) 20 (n = 8) and 50 (n = 8). Data were analyzed by a 3-way ANOVA testing the effects of conceptus health, tissue type and gestational day. RESULTS: Leptin and OB-Rb transcripts were significantly higher (P < 0.05) in pregnant than in non-pregnant sows. Significantly greater LEP (P < 0.001) was detected in the endometrial tissue at gd20 compared with gd50. At the protein level, the lowest LEP expression (P < 0.01) was detected in the CAM at gd50, while OB-Rb protein was significantly lower (P < 0.01) at gd50 in the CAM than in the endometrium collected from gd20 and gd50 conceptus attachment sites. Immunofluorescence staining confirmed the expression of these proteins at both gestational days and in both tissue types. CONCLUSIONS: Changes in the expression patterns of LEP and OB-Rb between gd20 and gd50 suggest a role for the LEP/OB-R complex at the early stages of porcine pregnancy, possibly affecting the attachment process. Further mechanistic studies are warranted to understand the specific role of leptin in porcine pregnancy.

Role of age and sex in the incidence of adverse effects among diabetic patients treated with glipizide.

Glipizide is an antidiabetic drug that belongs to a class of medication known as sulfonylureas. It is considered one of the highly prescribed antidiabetic drugs for the treatment of type II diabetes in patients following a kidney transplant. It lowers blood glucose levels by causing the release of insulin from ß-cells in the pancreas. Its main metabolizing pathway is through the liver. It has several adverse effects, which range from an upset stomach to glipizide-induced haemolytic anaemia and hypoglycaemia. These adverse effects may be spontaneous, or they could have a genetic cause. The present study aimed to assess and document the incidence of glipizide-induced adverse reactions among patients prescribed the drug. The present retrospective case-control study used the electronic medical records of patients prescribed glipizide for the past 3 years. These records were reviewed to extract and document cases and/or signs of glipizide-induced adverse reactions. The results revealed that the incidence of adverse effects was higher among female patients (odds ratio, 2.40, P<0.001). Moreover, the results revealed that the likelihood of developing adverse drug reactions among patients <40 years of age was higher than in older patients (P>0.05). The outcomes of the present study are expected to prompt future studies to take sex and age into consideration, in an aim to improve treatment outcomes, reduce adverse events and decrease the burden of unnecessary costs for healthcare systems. Recommendations also include genetic screening prior to administering the medication, educating the patients and caregivers on the possibility of adverse drug reactions, and routine follow-up. This issue is of utmost importance to achieve the optimal outcomes with the minimal detrimental effects.

A highlight on carbamazepine-induced adverse drug reactions in Saudi Arabia: a retrospective medical records-based study.

The link between human leukocyte antigen (HLA) alleles and carbamazepine-induced cutaneous, respiratory, and gastrointestinal adverse drug reactions (ADR) has created a window of opportunity for preventing certain forms of cutaneous adverse drug reactions (cADRs); however, there is not enough data to make pharmacogenomic recommendations that can be implemented globally. The aim of this study is to assess and document carbamazepine-induced adverse reactions among prescribed Saudi/non-Saudi patients. A retrospective chart review was performed for patients who received carbamazepine (CBZ) in the period between 2016 and 2020, in the Kingdom of Saudi Arabia. Data were gathered and descriptive statistical analyses were performed on the data for the study sample. Comparisons were made using the chi-square test or independent samples' t-test. Statistical significance was considered at p < .05. All statistical analyses were performed using IBM SPSS 21.0 (Armonk, NY; IBM Corp). Results from multivariate logistic regression analyses showed that higher likelihood of carbamazepine-induced adverse reactions was significantly associated with younger age, OR = 0.82, 95% CI (0.74, 0.90); p < 0.001. Patients who were prescribed CBZ for reasons other than epilepsy or seizures were significantly more likely to develop carbamazepine-induced adverse reactions (epilepsy vs. other; OR = 0.63, p = 0.013; seizures vs. other; OR = 0.59, p = 0.018). Gender or medication duration were not related to carbamazepine-induced adverse reactions (p > 0.05). The findings of this study are comparable with those of other studies assessing carbamazepine-associated adverse reactions in children and adults. Recommendations include genetic prescreening, educating patients and parents on the possibility of adverse reactions, and routine laboratory monitoring.

The use of melatonin and progestagen-eCG to initiate reproductive activity in prepuberal Awassi ewe lambs.

This experiment was conducted to evaluate the effect of administering hormonal treatments (melatonin and progestagen/equine chronic gonadotropin (eCG)) on advancing puberty in Awassi ewe lambs. Fifty-one 6-month-old ewe lambs of similar body weights (around 28 kg) were randomly assigned into four treatment groups; control (CON; n = 14), melatonin (MEL; n = 13), melatonin plus progestagen-eCG (MELPP; n = 11), and progestagen-eCG (PP; n = 13). Ewe lambs in the PP and MELPP groups were fitted with intravaginal progestagen sponges containing 60 mg medroxyprogesterone acetate for 14 days; 400 IU eCG were administered to each of these ewe lambs on the day of sponge removal. Ewe lambs in the MEL and MELPP groups received subcutaneous melatonin implants (Regulin®, 18 mg melatonin) 36 days before sponge insertion. Hormonal treatment had no effect on ewe lamb body weight change. Estrous behavior was greater (p < 0.001) in the PP and MELPP groups than in the CON and MEL ewe lambs. The duration from ram introduction to onset of estrus was shorter (p < 0.05) in the CON, PP, and MELPP than in the MEL ewe lambs. The number of ewe lambs showing luteal activity was greater (p < 0.001) in the MELPP and PP than in the CON and MEL groups. Lambing rate from mating during the first cycle following ram introduction differed significantly (p < 0.01) among treatments being greater in the MELPP and PP than in the CON and MEL groups. Based on these results, it can be concluded that progestagen-eCG appears to be more effective than melatonin in inducing reproductive activity. However, the majority of ewe lambs in the current study either failed to cycle or stopped cycling following the induced estrus. Such failure in advancing puberty may be related to body weight of ewe lambs at the time of mating.

Mechanisms underlying gut dysfunction in a murine model of chronic parasitic infection.

Irritable bowel syndrome (IBS) is common in countries where chronic parasitic infestations are endemic. However, the relationship between parasitic infection and IBS is not clear. The aim of this study was to examine whether chronic parasitic infection is accompanied by gut dysfunction and whether the continued presence of the parasite is required for the maintenance of the dysfunction. We used chronic Trichuris muris infection in Th1-biased susceptible AKR mice to evaluate this relationship. AKR mice were infected with T. muris and were euthanized on various days postinfection (pi) to examine worm burden, muscle function, and immune and inflammatory responses. Mice were treated with the anthelmintic oxantel pamoate to assess the effect of eradication of infection on muscle function. Infection resulted in persistence of the parasite, elevated IFN-γ, and increased MPO activity evident at 45 days pi. This was accompanied by a reduction in muscle contractility and excitatory innervation. Whereas parasite eradication at 7 days pi normalized IFN-γ and muscle contractility, eradication at 28 days pi failed to normalize muscle contractility. Administration of dexamethasone after parasite eradication normalized all parameters. Anthelmintic treatment improved histology except for eosinophils, which were normalized by subsequent dexamethasone therapy. Persistent gut dysfunction is independent of the continued presence of the parasite and is maintained by inflammatory process that includes eosinophils. Thus data in this preclinical model suggest that parasitic infection could be a cause of IBS, and the lack of symptomatic improvement following eradication is insufficient evidence to refute a causal relationship between the infection and IBS.

Serotonin has a key role in pathogenesis of experimental colitis.

BACKGROUND & AIMS: Mucosal changes in inflammatory bowel disease are characterized by ulcerative lesions accompanied by a prominent infiltrate of immune cells as well as alteration in serotonin (5-hydroxytryptamine [5-HT])-producing enterochromaffin cells. We investigated the role of 5-HT in colonic inflammation in mice. METHODS: Colitis was induced with dextran sulfate sodium or dinitrobenzene sulfonic acid in tryptophan hydroxylase 1-deficient (TPH1(-/-)) mice, which have markedly reduced 5-HT in the gastrointestinal tract, and in mice given the 5-HT synthesis inhibitor parachlorophenylalanine. RESULTS: Delayed onset, decreased severity of clinical disease, and significantly lower macroscopic and histologic damage scores were observed in TPH1(-/-) mice, compared with wild-type mice, and in mice given parachlorophenylalanine after induction of colitis by dextran sulfate sodium. This was associated with down-regulation of macrophage infiltration and production of proinflammatory cytokines. 5-HT stimulated production of proinflammatory cytokines from macrophages collected from the peritoneal cavity of wild-type mice; this process was inhibited by a nuclear factor kappaB inhibitor, indicating a critical role for nuclear factor kappaB signaling in 5-HT-mediated activation of immune cells. Restoration of 5-HT levels in TPH1(-/-) mice by the 5-HT precursor 5-hydroxytryptophan increased the severity of DSS-induced colitis. We also observed significant reduction in severity of colitis in TPH1(-/-) mice after induction of dinitrobenzene sulfonic acid-induced colitis. CONCLUSIONS: 5-HT is involved in the pathogenesis of inflammation in experimental colitis. These findings provide insight into the mechanisms of gastrointestinal inflammation and could lead to new therapeutic strategies for inflammatory disorders.

The current practice of using angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers in diabetic hypertensive and non-hypertensive patients. Is there a room for vitamin D?

OBJECTIVES: To determine the current pattern of using angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) in diabetic nephropathy (DN), and assess physician awareness of using vitamin D in the prevention and treatment of DN. METHODS: A cross-sectional study implementing a validated questionnaire, which was distributed to physicians in the aforementioned specialties in 3 hospitals in Saudi Arabia (Almanee Hospital, King Saud Medical City [KSMC], and Riyadh Care Hospital [RCH]) between April 2019 and November 2019. We used IBM SPSS 26.0 to perform descriptive statistical analyses and comparisons were based on the Chi-square test. RESULTS: Forty-one physicians (30%) reported the use of combination therapy of ACEi and ARBs. Fifty-six (41%) physicians reported that they never used vitamin D in the treatment of DN, and 48% agreed that vitamin D can benefit patients with DN. 52% of the respondents reported the existence of guidelines. The vast majority (94%) recommended clearer guidelines on monitoring renal function in patients treated with ACEi or ARBs. CONCLUSION: There is a universal agreement among physicians regarding the use of ACEi and ARBs for the treatment of DN with limited awareness of the bene ts of using vitamin D. Hence, the development of specific guidelines for its use are recommended.

Replacing Soybean Meal with Sesame Meal in the Diets of Lactating Awassi Ewes Suckling Single Lambs: Nutrient Digestibility, Milk Production, and Lamb Growth.

Two experiments were conducted to assess the influence of sesame meal (SM) feeding on nutrient digestibility, N balance, milk production and composition, ewes' body weight change, and growth performance of lambs. In experiment 1, 18 ewe lambs were randomly distributed into three diets to evaluate the effects of soybean meal replacement with SM on nutrient intake, digestibility, and N balance. Treatments were no SM (SM0), 7.5% SM (SM7.5), or 15% SM (SM15) of the dietary dry matter (DM). Aside from intake and digestibility of ether extract (EE), which was greater in the SM-containing diets compared with SM0, intake and digestibility of the remaining nutrients was similar among dietary treatments. In experiment 2, 30 ewes suckling single lambs were randomly assigned to the same diets used in experiment 1. Intakes of DM, crude protein, neutral detergent fiber, and acid detergent fiber were unaffected by treatment. Milk yield was greater in SM diets than in the SM0 diet. Cost/kg of milk production decreased while feed efficiency improved in the SM-diets compared to the SM0 diet. In conclusion, results of the current studies demonstrate the possibility of replacing soybean meal with sesame meal in diets of lactating Awassi ewes.

Twofold Porosity and Surface Functionalization Effect on Pt-Porous GaN for High-Performance H2-Gas Sensors at Room Temperature.

The achievement of H2 detection, up to 25 ppm, at room temperature using sulfur-treated, platinum (Pt)-decorated porous GaN is reported in this study. This achievement is attributed to the large lateral pore size, Pt catalyst, and surface treatment using organic sulfide. The performance of H2-gas sensors is studied as a function of the operating temperature by providing an adsorption activation energy of 22 meV at 30 ppm H2, confirming the higher sensitivity of the sulfide-treated Pt-porous GaN sensor. Furthermore, the sensing response of the sulfide-treated Pt-porous GaN gas sensor increases with the increase in porosity (surface-to-volume ratio) and pore radii. Using the Knudsen diffusion-surface reaction equation, the H2 gas concentration profile is simulated and fitted within the porous GaN layer, revealing that H2 diffusion is limited by small pore radii because of its low diffusion rate. The simulated gas sensor responses to H2 versus the pore diameter show the same trend as observed for the experimental data. The sulfide-treated Pt-porous GaN sensor achieves ultrasensitive H2 detection at room temperature for 125 nm pore radii.

Medical students' attitude toward anesthesia as a future career.

OBJECTIVES: The purpose of this study is to understand the attitude of medical students at King Saud bin Abdulaziz University for Health Sciences (KSAU-HS) toward anesthesia as a specialty and to determine common factors influencing their career choice options. STUDY DESIGN: This was a cross-sectional study. METHODS: The study was conducted between March 25, and April 20, 2017, at KSAU-HS. The survey was distributed among 5th and 6th years medical students. Data were collected through a validated hardcopy questionnaire of 16 multiple choice questions. The questionnaire included demographic characteristics, specialty preferences, what factors attract Saudi medical students to choose their preferred specialty and how they view the option of choosing anesthesiology as a career. RESULTS: A total of 236 students completed the questionnaire. The majority of respondents were in their 5th year of medical school representing (62%). The distribution of medical field interest ranged from (38%) surgery to (1%) anesthesiology. approximately, (60%) thought that controllable lifestyle was an important factor to consider in choosing a residency program. Only (45%) of respondents thought that prestige of specialty is a major factor that would influence their choice for a specialty. CONCLUSION: Based on the outcome of the study, it is recommended that medical undergraduate students exposure to anesthesia specialty should be magnified. Greater efforts have to be made to increase the number of medical students preferring anesthesia through emphasizing on the positive aspects of the specialty.

Validity and reliability of the Arabic version of the the EuroQOL (EQ-5D). A study from Saudi Arabia.

OBJECTIVES: The EuroQOL five-dimension questionnaire (EQ-5D) is one of the most widely used tools to evaluate health-related quality of life (HRQOL). Studies on the psychometric features of the EQ-5D in the Gulf region of the Middle East are lacking. This study is aimed at evaluating the validity and reliability of the Arabic version of the EQ-5D in Saudi Arabia. METHODS: The study was done utilizing a convenience sample of Arabic-speaking adult patients or visitors at the outpatient clinic at King Abdulaziz Medical City (KAMC) in Riyadh during October-December 2015. Participants were interviewed using translated into Arabic versions of the EQ-5D and the Short Form Health Survey (SF-36). Known-group construct validity of the EQ-5D and visual analog scale (EQ-VAS) was assessed through testing a number of hypotheses comparing responses to EQ-5D dimensions or EQ-VAS to SF-36 scores by dimension and external variables. Test-retest reliability was also assessed. RESULTS: Eighty subjects were included in the study. Mean ± standard deviartion age was 33.0 ± 11.6 years, with 51% of females. Responses to EQ-5D dimensions revealed that the proportion of respondents reporting problems ranged from 6% for problems with self-care to 48% for pain/discomfort. All of the five hypotheses linking EQ-5D responses to external variables were satisfied. Test-retest reliability was evaluated using Cohen's κ, which ranged from 0.53 to 1.00. CONCLUSION: Validity and reliability of the Arabic EQ-5D were established for evaluating HRQOL in Saudi Arabia. Further studies are warranted to evaluate the validity and reliability of this standard tool in other Arabic-speaking countries with varying cultures.

Acute Kidney Injury in Pediatric Treated with Vancomycin and Piperacillin-Tazobactam in Tertiary Care Hospital.

BACKGROUND: Vancomycin and piperacillin-tazobactam (PTZ) are commonly used as empirical therapy for patients with health care associated infections. Vancomycin has been recognized as a nephrotoxic agent and in a few cases in the literature PTZ has been associated with interstitial nephritis nevertheless; the combination of these agents has routinely been used for many years. However, there have been some observational studies that showed high rates of acute kidney injury (AKI) in patients receiving vancomycin and PTZ concomitant treatment compared to patients receiving vancomycin alone. The incidence of AKI in adult patients receiving vancomycin and PTZ concomitant treatment was reported in these studies to be relatively high. Similar studies in pediatric patients are lacking. METHOD: We conducted a single center retrospective chart review of 248 pediatric patients receiving one of the following treatments: vancomycin alone 36 patients, vancomycin/PTZ 62 patients, vancomycin/ceftazidime 99 patients, and vancomycin/ceftriaxone 51 patients. RESULT: Our results showed a low incidence of AKI in patients on vancomycin/PTZ concomitant treatment where overall incidence was only (4.8%) three cases and only one of them (2.0%) in a patient receiving the vancomycin/ceftriaxone concomitant treatment. No cases of AKI present in patients receiving vancomycin with ceftazidime or vancomycin alone. There were no statistically significant differences between the four treatment groups in terms of AKI incidence, vancomycin trough, and use of nephrotoxins. CONCLUSION: Overall, the incidence of AKI was low in our study sample with no statistically significant increased risk when PTZ was used in combination with vancomycin in a pediatric population. However, further investigation with an equal larger sample size is needed to confirm our findings.

The effects of Saccharomyces cerevisiae supplementation on intake, nutrient digestibility, and rumen fluid pH in Awassi female lambs.

AIM: The aim of this study was to evaluate the effect of feeding low (LO)- or high (HI)-fiber diets supplemented with Saccharomyces cerevisiae (SC) on nutrient intake, digestibility, nitrogen balance, rumen fluid pH, and serum concentrations of glucose and urea nitrogen in Awassi female lambs in a 2×2 factorial arrangement of treatments. MATERIALS AND METHODS: Experimental diets were as follows: (1) LO-fiber diet with no SC supplementation (-LO), (2) LO-fiber diet supplemented with SC (+LO), (3) HI-fiber diet with no SC supplementation (-HI), or (4) HI-fiber diet supplemented with SC (+HI). Eight female lambs were used in a replicated 4×4 Latin square design with 15-day experimental periods (10-day adaptation period and 5-day collection period). RESULTS: A fiber×SC interaction (p≤0.05) was detected for dry matter (DM) and crude protein (CP) intake among diets showing greater DM and CP intake for +LO diet compared to +HI group supplemented with SC, whereas -LO and -HI were intermediate. A fiber×SC interaction (p=0.05) was also detected for the neutral detergent fiber (NDF) intake among diets. Intake of NDF was greater for the -HI diet compared with +LO and -LO diets. Similarly, NDF intake was greater for +HI diet than -LO diet. A tendency (p=0.07) for a fiber×SC interaction was detected for acid detergent fiber (ADF) intake among diets as well. ADF intake tended to be greater for HI-fiber diets. No difference was observed in the rumen fluid pH for lambs fed with the different diets. No fiber×SC interactions were detected for the digestibility of DM, CP, NDF, and ADF among dietary treatments. Digestibility of DM was greater (72.9 g/100 g vs. 67.1 g/100 g; p=0.0002) for LO versus HI fiber. However, NDF and ADF digestibilities were greater (60.8 and 61.9 g/100 g vs. 55.8 and 52.7 g/100 g for NDF and ADF digestibility, respectively; p≤0.01) for the HI-fiber than the LO-fiber diets. CONCLUSION: Results obtained in the current study indicate that SC supplementation has a minimal effect on the performance of Awassi female lambs fed with varying fiber levels.

Functional and clinical characterization of a mutation in KCNJ2 associated with Andersen-Tawil syndrome.

BACKGROUND: Andersen-Tawil syndrome (ATS) is a rare inherited disorder, characterised by periodic paralysis, cardiac dysarrhythmias, and dysmorphic features, and is caused by mutations in the gene KCNJ2, which encodes the inward rectifier potassium channel, Kir2.1. This study sought to analyse KCNJ2 in patients with familial ATS and to determine the functional characteristics of the mutated gene. METHODS AND RESULTS: We screened a family with inherited ATS for the mutation in KCNJ2, using direct DNA sequencing. A missense mutation (T75R) of Kir2.1, located in the highly conserved cytoplasmic N-terminal domain, was identified in three affected members of this family. Using the Xenopus oocyte expression system and whole cell voltage clamp analyses, we found that the T75R mutant was non-functional and possessed a strong dominant negative effect when co-expressed with the same amount of wild type Kir2.1. Transgenic (Tg) mice expressing the mutated form of Kir2.1 in the heart had prolonged QTc intervals compared with mice expressing the wild type protein. Ventricular tachyarrhythmias were observed in 5 of 14 T75R-Tg mice compared with 1 of 7 Wt-Tg and none of 6 non-transgenic littermates. In three of five T75R-Tg mice with ventricular tachycardia, their ECG disclosed bidirectional tachycardia as in our proband. CONCLUSIONS: The in vitro studies revealed that the T75R mutant of Kir2.1 had a strong dominant negative effect in the Xenopus oocyte expression system. It still preserved the ability to co-assemble and traffic to the cell membrane in mammalian cells. For in vivo studies, the T75R-Tg mice had bidirectional ventricular tachycardia after induction and longer QT intervals.

Extracellular vesicle mediated intercellular communication at the porcine maternal-fetal interface: A new paradigm for conceptus-endometrial cross-talk.

Exosomes and microvesicles are extracellular vesicles released from cells and can contain lipids, miRNAs and proteins that affect cells at distant sites. Recently, microvesicles containing miRNA have been implicated in uterine microenvironment of pigs, a species with unique epitheliochorial (non-invasive) placentation. Here we report a novel role of conceptus-derived exosomes/microvesicles (hereafter referred to as extracellular vesicles; EVs) in embryo-endometrial cross-talk. We also demonstrate the stimulatory effects of EVs (PTr2-Exo) derived from porcine trophectoderm-cells on various biological processes including the proliferation of maternal endothelial cells (PAOEC), potentially promoting angiogenesis. Transmission immuno-electron microscopy confirmed the presence of EVs in tissue biopsies, PTr2-Exo and PAOEC-derived EVs (PAOEC-Exo). RT-PCR detected 14 select miRNAs in CD63 positive EVs in which miR-126-5P, miR-296-5P, miR-16, and miR-17-5P were the most abundant angiogenic miRNAs. Proteomic analysis revealed EV proteins that play a role in angiogenesis. In-vitro experiments, using two representative cell lines of maternal-fetal interface, demonstrated bidirectional EVs shuttling between PTr2 and PAOEC cells. Importantly, these studies support the idea that PTr2-Exo and PAOEC-Exo containing select miRNAs and proteins can be successfully delivered to recipient cells and that they may have a biological role in conceptus-endometrial cross-talk crucial for the pregnancy success.