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Irma Olarte Carrillo,1 Christian Omar Ramos Peñafiel,2 Iveth Mendoza Salas,2 Rafael Cerón Maldonado,1 Anel Irais García Laguna,1 Adrián De la Cruz Rosas,1 Carlos Martinez Murrillo,2 Adolfo Martinez Tovar1 1Laboratorio de Biología Molecular, Servicio de Hematología, Hospital General de México, “Dr. Eduardo Liceaga”, Ciudad de México, Mexico; 2Servicio de Hematología, Hospital General de México, “Dr. Eduardo Liceaga”, Ciudad de México, MexicoCorrespondence: Adolfo Martinez Tovar, Labortororio de Biología Molecular, Servicio de Hematología, Hospital General de Mexico “Dr. Eduardo Liceaga”, Ciudad de México, Mexico, Email mtadolfo73@hotmail.comObjective: In the last two years progress was made in molecular, physio pathological understanding and the form of transmission of COVID-19, and different therapeutic strategies have been explored to deal with the situation of the pandemic. However, the evaluation of certain genes that participate in the metabolism and transport of these drugs has not been fully explored. A lack of response to treatment and a lower survival have been observed that may be due to the presence of the ABCB1 drug resistance gene. Our research group analyzed whether the expression levels of the ABCB1 gene are associated with comorbidities, treatments, overall survival and risk of death in patients with severe COVID-19.Methods: The expression levels of the ABCB1 gene were analyzed by RT-qPCR in 61 patients diagnosed with COVID-19. The association between the levels of expression, the risk variables and different treatments were determined by the Chi-Square test and the Fisher’s exact test. Global Survival (GS) was determined by the Kaplan–Meier method. The impact of high levels of expression and the risk of death was performed by odds ratio.Results: The different risk variables showed that patients with either high or absent levels of ABCB1 gene expression presented a greater risk of death (OR 3.08, 95%, CI 1.02– 9.26) as well as need for ventilatory support (OR 2.8, 95%, CI 0.98 − 8.5). Patients with diabetes and COVID-19, treated with metformin, were associated with a lower risk of death (OR 1.11, 95%, CI 0.38– 3.22). OS with respect to high or absent levels of expression of the ABCB1 gene was lower.Conclusion: High levels or null expression of the ABCB1 gene are associated with a higher risk of death or progression of the disease, the use of metformin in patients with COVID-19 confers a lower risk of death.Keywords: ABCB1, SARS-CoV2, drug transporter genes

Lattice plasmon lasers demonstrated to have many degrees of freedom useful to tailor the lasing properties, as the tuning of the morphological properties of the array or the coupling of proper emitters to band-edge states of the plasmonic crystal. Here, we present the results of the study of the lasing emission properties of a hexagonal array of aluminum nanoparticles as a function of the pumping conditions. We demonstrate how the geometrical and dynamic features of the pumping system have a significant impact on the lasing properties without affecting the temporal coherence of the emission. Moreover, by combining different pumping systems and studies at different incidence angles, the relationship between nanoarray, dye and pump has been clarified.

Abstract Background The hallmark characteristic of autism is impaired reciprocal social interaction. While children find social interaction stress-reducing, many children with autism may find social interaction stress-inducing. The current study was designed to examine stress responsivity as measured by cortisol by comparing children with autism to neurotypical peers during an ecologically valid 20-minute playground paradigm. Methods The experiment involved sets of three children: a child with autism, a neurotypical child, and a confederate. Participants included 45 prepubescent males between 8 and 12 years of age (21 with autism and 24 neurotypical children). Results Children with autism showed fewer initiations (χ²(1) = 4.03, P = 0.044), rejected initiations from others more (χ²(1) = 7.10, P = 0.008) and spent less time interacting during motor (F(1,43) = 16.7, P = 0.0002) and cooperative (F(1,43) = 14.78, P = 0.0004) play. Repeated measures analysis of the cortisol values revealed a significant model (χ²(4) = 22.76, P < 0.0005) that included time of measurement, diagnosis and age as main effects and an interaction between diagnosis and age. Thus, as age increased among children with autism, they experienced enhanced cortisol levels while age did not modify expected cortisol levels for typical children. Stress responsivity was associated with more peripheral equipment play for motor (χ²(3) = 12.3, P = 0.006) and cooperative (χ²(3) = 8.24, P = 0.04) play as well as reduced nonverbal social skills during motor (χ²(1) = 5.52, P = 0.018) and cooperative play (χ²(1) = 4.53, P = 0.033). Conclusions Overall, children with autism engaged in fewer social overtures and spent less time interacting than typically developing peers during play. The peer interaction paradigm resulted in significantly higher levels of cortisol in many children with autism. Distinct patterns emerged within the autism group based on developmental (older), biological (cortisol responder) and behavioral patterns (peripheral group interaction). The enhanced cortisol response was observed in children who voluntarily engaged in interaction; thus, it does not support the notion of a response to social threat. Rather, it appears to reflect attendant metabolic preparedness and enhanced arousal from engaging socially. The data suggest that many children with autism activate hypothalamic-pituitary-adrenal responses in relatively benign social situations, which appears to be a function of age and level of social engagement. The findings support the need to teach coping strategies in addition to fundamental social skills to youth with autism.

Major cardiovascular events (MACEs) are a cause of major mortality worldwide. The narrowing and blockage of coronary arteries with atherosclerotic plaques are diagnosed and treated with percutaneous coronary intervention (PCI). During this procedure, coronary angiography (CAG) remains the most widely used guidance modality for the evaluation of the affected blood vessel. The measurement of the blood vessel diameter is an important factor to consider in order to decide if stent colocation is suitable for the intervention. In this regard, a small blood vessel (<2.75 mm) is majorly left without stent colocation; however, small vessel coronary artery disease (SvCAD) is a significant risk factor for the recurrence of MACEs, maybe due to the lack of a standardized treatment related to the diameter of the affected blood vessel; therefore, a more precise measurement is needed. The use of CAG for the measurement of the blood vessel diameter has some important limitations that can be improved with the use of newer techniques such as intravascular ultrasound (IVUS), although at higher costs, which might explain its underuse. To address differences in blood vessel diameter measurements and identify specific cases where IVUS might be of additional benefit for the patient, we conducted a retrospective study in patients who underwent PCI for MACEs with affection for at least one small blood vessel. We compared the measurements of the affected small blood vessels' diameter obtained by CAG and IVUS to identify cases of reclassification of the affected blood vessel; additionally, we underwent a multivariate analysis to identify risk factors associated with blood vessel reclassification. We included information from 48 patients with a mean ± SD age of 69.1 ± 11.9 years; 70.8% were men and 29.2% were women. The mean diameter with CAG and IVUS was 2.1 mm (95% CI 1.9-2.2), and 2.8 (2.8-3.0), respectively. The estimated difference was of 0.8 mm (95% CI 0.7-0.9). We found a significant positive low correlation in diameter measurements of small blood vessels obtained with CAG and IVUS (r = 0.1242 p = 0.014). In total, 37 (77%) patients had a reclassification of the affected blood vessel with IVUS. In 21 cases, the affected blood vessel changed from a small to a medium size (2.75-3.00 mm), and in 15 cases, the affected vessel changed from a small to a large size (<3.00 mm). The Bland-Altman plot was used to evaluate agreement in measurements with CAG and IVUS. The change in blood vessel classification with IVUs was important for the decision of intervention and stent collocation. The only variable associated with reclassification of blood vessels after adjustment in a multivariate analysis was T2D (type 2 diabetes) ( p = 0 0.035). Our findings corroborate that blood vessels might appear smaller with CAG, especially in patients with T2D; therefore, at least in these cases, the use of IVUS is recommended over CAG.

The transportation sector is among the highest contributors to the increase in greenhouse gas emissions in European nations, with private cars emerging as the primary source. Although reducing emissions presents a formidable challenge, the emergence of battery electric vehicles (BEVs) offers a promising and sustainable avenue toward achieving zero greenhouse gases within the transportation infrastructure. Since the 1990s, the Norwegian parliament has fervently supported this transition, leveraging public awareness campaigns and a range of financial incentives for its users nationwide. The widespread utilization of BEVs promises substantial health benefits, including ensuring cleaner air for all citizens regardless of their socioeconomic status and fostering improvements in public health outcomes. This transition potentially curtails hundreds of thousands of annual deaths attributed to climate change, enhances the quality of life, bolsters civilian productivity, and fuels economic and population growth. The adoption of BEVs offers a myriad of advantages, including reduced health risks and premature mortality, as well as a quieter environment with diminished noise pollution. Nonetheless, the integration of BEVs necessitates robust road infrastructure with considerable maintenance costs, alongside limitations on driving range for users. Concerns arise regarding potential particle emissions from BEV tire wear due to the increased weight of batteries compared to conventional vehicles. Rapid acceleration capabilities may accelerate tire degradation, contributing to higher particle emissions, of which only 10% to 20% remain suspended in the air, whereas the majority settles on road surfaces, posing a threat to nearby aquatic ecosystems when washed into water bodies and soils. While BEVs hold promise for valuable benefits, successful policy creation and implementation require a detailed awareness of their limitations and challenges to ensure a comprehensive approach to sustainable mobility and public health improvement. Therefore, more research on the limitations of BEVs can help inform improved tactics for maximizing their benefits while limiting potential disadvantages., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2024.)

Currently, the food and economic losses generated by the attack of phytopathogens on the agricultural sector constitute a severe problem. Conventional crop protection techniques based on the application of synthetic pesticides to combat these undesirable microorganisms have also begun to represent an inconvenience since the excessive use of these substances is associated with contamination problems and severe damage to the health of farmers, consumers, and communities surrounding the fields, as well as the generation of resistance by the phytopathogens to be combated. Using biocontrol agents such as Trichoderma to mitigate the attack of phytopathogens represents an alternative to synthetic pesticides, safe for health and the environment. This work explains the mechanisms of action through which Trichoderma exerts biological control, some of the beneficial aspects that it confers to the development of crops through its symbiotic interaction with plants, and the bioremedial effects that it presents in fields contaminated by synthetic pesticides. Also, detail the production of spore-based biopesticides through fermentation processes and formulation development., (© 2023. The Author(s), under exclusive licence to Springer Nature B.V.)

This study corresponds to the first large-scale genetic analysis of inherited eye diseases (IED) in Argentina and describes the comprehensive genetic profile of a large cohort of patients. Medical records of 22 ophthalmology and genetics services throughout 13 Argentinian provinces were analyzed retrospectively. Patients with a clinical diagnosis of an ophthalmic genetic disease and a history of genetic testing were included. Medical, ophthalmological and family history was collected. A total of 773 patients from 637 families were included, with 98% having inherited retinal disease. The most common phenotype was retinitis pigmentosa (RP, 62%). Causative variants were detected in 379 (59%) patients. USH2A, RPGR, and ABCA4 were the most common disease-associated genes. USH2A was the most frequent gene associated with RP, RDH12 early-onset severe retinal dystrophy, ABCA4 Stargardt disease, PROM1 cone-rod dystrophy, and BEST1 macular dystrophy. The most frequent variants were RPGR c.1345 C > T, p.(Arg449*) and USH2A c.15089 C > A, p.(Ser5030*). The study revealed 156/448 (35%) previously unreported pathogenic/likely pathogenic variants and 8 possible founder mutations. We present the genetic landscape of IED in Argentina and the largest cohort in South America. This data will serve as a reference for future genetic studies, aid diagnosis, inform counseling, and assist in addressing the largely unmet need for clinical trials to be conducted in the region., (© 2023. The Author(s).)

The theory of enclothed cognition proposes that wearing physical articles of clothing can trigger psychological processes and behavioral tendencies connected to their symbolic meaning. Furthermore, past research has found that increases in power are associated with greater approach orientation and action tendencies. In this study, we integrate these two literatures to examine how embodying the role of a police officer through wearing a uniform would affect responses on a reaction-time measure known as the Shooter Task. This first-person video game simulation requires participants to shoot or not shoot targets holding guns or objects. The task typically elicits a stereotypical pattern of responses, such that unarmed Black versus White targets are more likely to be mistakenly shot and armed Black versus White targets are more likely to be correctly shot. Based on the relationship between power and action, we hypothesized that participants who were randomly assigned to wear a police uniform would show more shooting errors, particularly false alarms, than control participants. Consistent with our hypotheses, participants in uniform were more likely to shoot unarmed targets, regardless of their race. Moreover, this pattern was partially moderated by attitudes about the police and their abuse of power. Specifically, uniformed participants who justified police use of power were more likely to shoot innocent targets than those who were wary of it. We discuss implications for police perceptions and the theory of enclothed cognition more broadly.

Kidney transplant (KT) is the first therapeutic option for most patients with chronic renal failure that requires renal function replacement. The main complication associated with renal graft loss is immune rejection. The T regulatory pathways play a key role in this process, and abnormalities in some of these molecules could participate in the graft rejection. In this paper, our group performed an exploratory analysis of the behavior of the coinducible molecules (CD28, CTLA-4, ICOS, PD-1) in patients with KT rejection and control KT patients without rejection. The Mann-Whitney U test, used for 2 groups, showed significant differences (P = .0005), indicating that PD-1 is underexpressed in patients with allograft rejection. No differences were found in CD28+, regulatory T cells (T reg), CTLA-4, and ICOS, so we are proposing that PD-1 is a key player in the immunotolerance phenomenon and its underexpression participates in the rejection process. More research needs to be performed on this topic., (Copyright © 2020 Elsevier Inc. All rights reserved.)

The present study examined if a social positive illusory bias (PIB) is: a) simply a reflection of low adult-rated social acceptance, b) evident when children's perceived social acceptance is measured implicitly, and c) directly relates to impaired executive functioning (EF). Participants were 8 to 12 year-old children (N = 120; 55 boys and 65 girls) with and without clinical symptoms of attention-deficit/hyperactivity disorder (ADHD). Ratings of the child's social acceptance were obtained from an adult and the child using the Self-Perception Profile for Children (Harter 2012); social bias was calculated as the discrepancy between standardized adult- and child-ratings. Children also completed a reaction time measure to assess implicit perceptions of social acceptance and a battery of EF measures. Depression symptoms were assessed based on parent report. Group comparisons were focused on the presence or absence of social PIB rather than on ADHD diagnostic status. Relative to non-PIB children, those with a social PIB were significantly higher in self-reported social acceptance, but significantly lower on adult reports and implicit perceived social acceptance; these children also were significantly higher in depression symptoms. EF impairments were indirectly related to social PIB as a function of adult-rated social impairment. Results suggest that social PIB is not merely a reflection of low adult-ratings of social acceptance. However, the high explicit self-reports of social acceptance in children with a social PIB are not fully consistent with their implicit self-perceptions of social acceptance. Results are discussed in light of the self-protective and cognitive deficits hypotheses regarding the nature of social PIB.

Background: Cleft lip and/or palate (CL/P) is the most common craniofacial anomaly., Objective: to determine the incidence of cleft lip and/or palate (CL/P) in patients born in the Hospital "Dr. Aurelio Valdivieso" in the city of Oaxaca between 2008 and 2010., Methods: A retrospective, cross-sectional study on all live births with non-syndromic orofacial cleft was realized. The variables included were CL/P presence, sex, and birth year. Clinical records of CL/P subjects were reviewed and clefts classified according to Kernahan and Stark. Tables were generated to present data., Results: The total number of live births (LB) was 24,043 for the 2008 to 2010 period. In 2008, 9 cases (rate 1.01 per 1,000 LB) were identified: 7 boys and 2 girls. In 2009, there were 4 cases (rate 0.54 per 1,000 LB), 3 boys and 1 girl. In 2010, there were 11 cases (rate 1.42 per 1,000 LB), 7 boys and 4 girls. The total for the period 2008-2010 were 24 cases (rate 1.00 per 1,000 LB), 17 boys and 7 girls. Incidence rate was higher among male than among female. As for the distribution according to Kernahan and Stark classification, there were 4 boys and 3 girls in group "C", 10 boys and 4 girls in group "D", and only 3 boys in group "E"; not a single case in groups "A" and "B"., Conclusions: The incidence for the period was 1.00 per 1,000 LB. The CL/P was more frequent in boys for each year included in the study.

Rationale: Hydrogen peroxide (H(2)O(2)) serves as a key endothelium-derived hyperpolarizing factor mediating flow-induced dilation in human coronary arterioles (HCAs). The precise mechanisms by which H(2)O(2) elicits smooth muscle hyperpolarization are not well understood. An important mode of action of H(2)O(2) involves the oxidation of cysteine residues in its target proteins, including protein kinase G (PKG)-Iα, thereby modulating their activities., Objective: Here we hypothesize that H(2)O(2) dilates HCAs through direct oxidation and activation of PKG-Iα leading to the opening of the large-conductance Ca(2+)-activated K(+) (BK(Ca)) channel and subsequent smooth muscle hyperpolarization., Methods and Results: Flow and H(2)O(2) induced pressure gradient/concentration-dependent vasodilation in isolated endothelium-intact and -denuded HCAs, respectively. The dilation was largely abolished by iberiotoxin, a BK(Ca) channel blocker. The PKG inhibitor Rp-8-Br-PET-cGMP also markedly inhibited flow- and H(2)O(2)-induced dilation, whereas the soluble guanylate cyclase inhibitor ODQ had no effect. Treatment of coronary smooth muscle cells (SMCs) with H(2)O(2) elicited dose-dependent, reversible dimerization of PKG-Iα, and induced its translocation to the plasma membrane. Patch-clamp analysis identified a paxilline-sensitive single-channel K(+) current with a unitary conductance of 246-pS in freshly isolated coronary SMCs. Addition of H(2)O(2) into the bath solution significantly increased the probability of BK(Ca) single-channel openings recorded from cell-attached patches, an effect that was blocked by the PKG-Iα inhibitor DT-2. H(2)O(2) exhibited an attenuated stimulatory effect on BK(Ca) channel open probability in inside-out membrane patches., Conclusions: H(2)O(2) dilates HCAs through a novel mechanism involving protein dimerization and activation of PKG-Iα and subsequent opening of smooth muscle BK(Ca) channels.

In human coronary arterioles (HCAs) from patients with coronary artery disease, flow-induced dilation is mediated by a unique mechanism involving the release of H(2)O(2) from the mitochondria of endothelial cells (ECs). How flow activates ECs to elicit the mitochondrial release of H(2)O(2) remains unclear. Here, we examined the role of the transient receptor potential vanilloid type 4 (TRPV4) channel, a mechanosensitive Ca(2+)-permeable cation channel, in mediating ROS formation and flow-induced dilation in HCAs. Using RT-PCR, Western blot analysis, and immunohistochemical analysis, we detected the mRNA and protein expression of TRPV4 channels in ECs of HCAs and cultured human coronary artery ECs (HCAECs). In HCAECs, 4α-phorbol-12,13-didecanoate (4α-PDD), a selective TRPV4 agonist, markedly increased (via Ca(2+) influx) intracellular Ca(2+) concentration. In isolated HCAs, activation of TRPV4 channels by 4α-PDD resulted in a potent concentration-dependent dilation, and the dilation was inhibited by removal of the endothelium and by catalase, a H(2)O(2)-metabolizing enzyme. Fluorescence ROS assays showed that 4α-PDD increased the production of mitochondrial superoxide in HCAECs. 4α-PDD also enhanced the production of H(2)O(2) and superoxide in HCAs. Finally, we found that flow-induced dilation of HCAs was markedly inhibited by different TRPV4 antagonists and TRPV4-specific small interfering RNA. In conclusion, the endothelial TRPV4 channel is critically involved in flow-mediated dilation of HCAs. TRPV4-mediated Ca(2+) entry may be an important signaling event leading to the flow-induced release of mitochondrial ROS in HCAs. Elucidation of this novel TRPV4-ROS pathway may improve our understanding of the pathogenesis of coronary artery disease and/or other cardiovascular disorders.

The implantation of cultured re-associations between embryonic dental mesenchymal cells and epithelial cells from mouse molars at embryonic day 14 (ED14) allowed making full teeth with crown, root, periodontal ligament fibers, and bone. Although representing valuable tools to set up methodologies embryonic cells are not easily available. This work thus aimed to replace the embryonic cells by dental mesenchymal cell lines or cultured expanded embryonic cells, and to test their ability to mediate tooth development in vitro when re-associated with a competent dental epithelium. Histology, immunostaining and RT-PCR allowed getting complementary sets of results. Two different immortalized cell lines from ED18 dental mesenchyme failed in mediating tooth formation. The potentialities of embryonic dental mesenchymal cells decreased from ED14 to ED16 and were lost at ED18. This is likely related to a change in the mesenchymal cell phenotype and/or populations during development. Attempts to cultivate ED14 or ED16 embryonic dental mesenchymal cells prior to re-association led to the loss of their ability to support tooth development. This was accompanied by a down-regulation of Fgf3 transcription. Supplementation of the culture medium with FGF2 allowed restoring Fgf3 expression, but not the ability of mesenchymal cells to engage in tooth formation. Altogether, these observations suggest that a competent cell population exists in the dental mesenchyme at ED14, progressively decreases during development, and cannot as such be maintained in vitro. This study evidenced the need for specific conditions to maintain the ability of dental mesenchymal cells to initiate whole tooth formation, when re-associated with an odontogenic epithelium. Efforts to improve the culture conditions will have to be combined with attempts to characterize the competent cells within the dental mesenchyme.

The authors tested the effectiveness of implementation intentions as a strategy for limiting the behavioral expression of implicit stereotypes. Implementation intentions are if-then plans that link an intended response to an anticipated situational cue, thereby enabling a reflexive form of control. The authors examined whether two different types of implementation intentions could improve response accuracy on the Shooter Task, a reaction time measure of implicit stereotyping. In Study 1, participants used a distraction-inhibiting implementation intention designed to engage control over the perception of goal-irrelevant stimuli (e.g., race). In Study 2, participants used a response-facilitating implementation intention designed to promote goal-directed action. Across studies, implementation intentions improved accuracy, thereby limiting the behavioral expression of implicit stereotypes. Furthermore, process dissociation analyses indicated that the distraction-inhibiting implementation intention increased controlled processing while reducing automatic stereotype activation, whereas the response-facilitating implementation intention increased only controlled processing. Implications for goal strategy approaches to reducing prejudice are discussed.

The transient receptor potential vallinoid type 4 (TRPV4) channel has been implicated in the endothelial shear response and flow-mediated dilation, although the precise functions of this channel remain poorly understood. In the present study, we investigated the role of TRPV4 in shear stress-induced endothelial Ca(2+) entry and the potential link between this signaling response and relaxation of small resistance arteries. Using immunohistochemical analysis and RT-PCR, we detected strong expression of TRPV4 protein and mRNA in the endothelium in situ and endothelial cells freshly isolated from mouse small mesenteric arteries. The selective TRPV4 agonist GSK1016790A increased endothelial Ca(2+) and induced potent relaxation of small mesenteric arteries from wild-type (WT) but not TRPV4(-/-) mice. Luminal flow elicited endothelium-dependent relaxations that involved both nitric oxide and EDHFs. Both nitric oxide and EDHF components of flow-mediated relaxation were markedly reduced in TRPV4(-/-) mice compared with WT controls. Using a fura-2/Mn(2+) quenching assay, shear was observed to produce rapid Ca(2+) influx in endothelial cells, which was markedly inhibited by the TRPV4 channel blocker ruthenium red and TRPV4-specific short interfering RNA. Flow elicited a similar TRPV4-mediated Ca(2+) entry in HEK-293 cells transfected with TRPV4 channels but not in nontransfected cells. Collectively, these data indicate that TRPV4 may be a potential candidate of mechanosensitive channels in endothelial cells through which the shear stimulus is transduced into Ca(2+) signaling, leading to the release of endothelial relaxing factors and flow-mediated dilation of small resistance arteries.

Objective: Hydrogen peroxide (H2O2) is an endothelium-derived hyperpolarizing factor in human coronary arterioles (HCAs). H2O2 mediates bradykinin (BK)-induced vasodilation and reduces bioavailability of epoxyeicosatrienoic acids (EETs); however, the cellular and enzymatic source of H2O2 is unknown., Methods and Results: NADPH oxidase expression was determined by immunohistochemistry. Superoxide and H2O2 production was assayed in HCAs and human coronary artery endothelial cells (HCAECs) using dihydroethidium and dichlorodihydrofluorescein histofluorescence, respectively. Superoxide was quantified by HPLC separation of dihydroethidium products. Diameter changes of HCAs were measured by videomicroscopy. NADPH oxidase subunits Nox1, Nox2, Nox4, p22, p47, and p67 were each expressed in HCA endothelium. In HCAs or HCAECs incubated with dihydroethidium and dichlorodihydrofluorescein, BK induced superoxide and H2O2 formation, which was inhibited by gp91ds-tat or apocynin but not by gp91scram-tat or rotenone. HPLC analysis confirmed that BK specifically induced superoxide production. Gp91ds-tat reduced vasodilation to BK but not to papaverine. 14,15-EEZE (an EET antagonist) further reduced the residual dilation to BK in the presence of gp91ds-tat, but had no effect in the presence of gp91scram-tat, suggesting that NADPH oxidase-derived ROS modulate EET bioavailability., Conclusion: We conclude that endothelial NADPH oxidase is a functionally relevant source of H2O2 that mediates agonist-induced dilation in the human heart.

Agonist-induced Ca2+ entry is important for the synthesis and release of vasoactive factors in endothelial cells. The transient receptor potential vanilloid type 4 (TRPV4) channel, a Ca2+-permeant cation channel, is expressed in endothelial cells and involved in the regulation of vascular tone. Here we investigated the role of TRPV4 channels in acetylcholine-induced vasodilation in vitro and in vivo using the TRPV4 knockout mouse model. The expression of TRPV4 mRNA and protein was detected in both conduit and resistance arteries from wild-type mice. In small mesenteric arteries from wild-type mice, the TRPV4 activator 4alpha-phorbol-12,13-didecanoate increased endothelial [Ca2+]i in situ, which was reversed by the TRPV4 blocker ruthenium red. In wild-type animals, acetylcholine dilated small mesenteric arteries that involved both NO and endothelium-derived hyperpolarizing factors. In TRPV4-deficient mice, the NO component of the relaxation was attenuated and the endothelium-derived hyperpolarizing factor component was largely eliminated. Compared with their wild-type littermates, TRPV4-deficient mice demonstrated a blunted endothelial Ca2+ response to acetylcholine in mesenteric arteries and reduced NO release in carotid arteries. Acetylcholine (5 mg/kg, IV) decreased blood pressure by 37.0+/-6.2 mm Hg in wild-type animals but only 16.6+/-2.7 mm Hg in knockout mice. We conclude that acetylcholine-induced endothelium-dependent vasodilation is reduced both in vitro and in vivo in TRPV4 knockout mice. These findings may provide novel insight into mechanisms of Ca2+ entry evoked by chemical agonists in endothelial cells.

Six1-/- mice were found to have apparently normal ureters in the absence of a kidney, suggesting that the growth and development of the unbranched ureter is largely independent of the more proximal portions of the UB which differentiates into the highly branched renal collecting system. Culture of isolated urinary tracts (from normal and mutant mice) on Transwell filters was employed to study the morphogenesis of this portion of the urogenital system. Examination of the ureters revealed the presence of a multi-cell layered tubule with a lumen lined by cells expressing uroplakin (a protein exclusively expressed in the epithelium of the lower urinary tract). Cultured ureters of both the wild-type and Six1 mutant become contractile and undergo peristalsis, an activity preceded by the expression of alpha-smooth muscle actin (alphaSMA). Treatment with a number of inhibitors of signaling molecules revealed that inhibition of PI3 kinase dissociates the developmental expression of alphaSMA from ureter growth and elongation. Epidermal growth factor also perturbed smooth muscle differentiation in culture. Moreover, the peristalsis of the ureter in the absence of the kidney in the Six1-/- mouse indicates that the development of this clinically important function of ureter (peristaltic movement of urine) is not dependent on fluid flow through the ureter. In keeping with this, isolated ureters cultured in the absence of surrounding tissues elongate, differentiate and undergo peristalsis when cultured on a filter and undergo branching morphogenesis when cultured in 3-dimensional extracellular matrix gels in the presence of a conditioned medium derived from a metanephric mesenchyme (MM) cell line. In addition, ureters of Six1-/- urinary tracts (i.e., lacking a kidney) displayed budding structures from their proximal ends when cultured in the presence of GDNF and FGFs reminiscent of UB budding from the wolffian duct. Taken together with the above data, this indicates that, although the distal ureter (at least early in its development) retains some of the characteristics of the more proximal UB, the growth and differentiation (i.e., development of smooth muscle actin, peristalsis and uroplakin expression) of the distal non-branching ureter are inherent properties of this portion of the UB, occurring independently of detectable influences of either the undifferentiated MM (unlike the upper portion of the ureteric bud) or more differentiated metanephric kidney. Thus, the developing distal ureter appears to be a unique anatomical structure which should no longer be considered as simply the non-branching portion of the ureteric bud. In future studies, the ability to independently analyze and study the portion of the UB that becomes the renal collecting system and that which becomes the ureter should facilitate distinguishing the developmental nephrome (renal ontogenome) from the ureterome.

Study Design: This study investigated tissue integrity and viability of cells in an organ culture system of intervertebral disc (IVD) with adjoining vertebral bodies., Objective: The goal of this study was to design a methodology to maintain an IVD motion segment in organ culture, thereby preserving viability and tissue architecture., Summary of Background Data: Study of IVD mechanobiology in vitro necessitates availability of vertebral bodies for controlled application of complex loads., Methods: IVD motion segments were dissected from rat lumbar segments and maintained in organ culture and cell viability was evaluated histochemically using NitroBlue Tetrazolium. Tissue integrity and morphology were evaluated using conventional histologic techniques., Results: The in vitro organ culture of motion segments maintained the viability and tissue integrity for 14 days. More than 95% viability in all three regions of interest (anulus fibrosus, nucleus pulposus, end plates) was maintained for 14 days in culture., Conclusion: Our initial results suggest that long-term motion segment culture is practical, and the inclusion of vertebral bodies will facilitate anchoring during biomechanical stimulation. Thus, we expect the culture system to provide us with an excellent model for studying the pathomechanics of IVD degeneration and the effects of mechanical stimulation on the biology of IVD cells.

Peritonitis is the most common complication and the leading cause of death in pediatric peritoneal dialysis (PD) patients. According to the most recent data available from the North American Pediatric Renal Transplant Cooperative Study (NAPRTCS), approximately 25% of pediatric PD patients who die succumb to infection. There are no reported cases of Mycobacterium tuberculosis (MTB) or Mycobacterium avium-intracellulare peritonitis in the NAPRTCS registry. With an increasing incidence of MTB worldwide and the impairment of cellular immunity in chronic renal failure patients, it is not surprising that mycobacterium peritonitis can occur in PD patients. We report two pediatric PD patients with mycobacterial peritoneal infection diagnosed over an 11-year period at our institution. One patient presented with a malfunctioning Tenckhoff catheter and again 3 years later with hyponatremia and ascites. The other presented with recurrent culture-negative peritonitis. These cases illustrate the importance of more extensive evaluation of PD complications, to include evaluation for mycobacterium with special media or peritoneal biopsy, in the above clinical settings if the routine work-up is unrevealing.

Toward an etiological classification of developmental disorders of the kidney and upper urinary tract. There are a large number of developmental disorders and syndromes that affect the kidney and upper urinary tract. These have generally been classified according to morphological criteria established decades ago. Although these classifications have been useful, they are incomplete, including some developmental disorders while excluding others. Here, basic cellular and molecular biology studies of kidney and upper urinary tract development in both rodents and humans are utilized to suggest the basis of a new etiologic, if still tentative, classification scheme. This classification may help to identify candidate genes for human diseases by correlating morphology with pathogenetic mechanisms.

This review compares the biopsy patterns, complications, responses to therapy, and long-term outcomes of idiopathic NS in children and adults. On first examination, distinctions between the pediatric and adult diseases seem more quantitative than absolute. However, underlying determinants of outcome, including immunocompetence, growth, maturity, and senescence, can present very different challenges for pediatricians and internists. The major biopsy patterns in pediatric NS include MCD, FSGS, and DMP. MCD is overwhelmingly the most frequent and most steroid-responsive of the three but commonly presents problems of massive edema, serious bacterial infections, and multiple relapses. Because of the prompt response of pediatric MCD to corticosteroids, steroid resistance in children has generally been defined as persistence of proteinuria after 1 month of daily followed by 1 month of intermittent prednisone administration. By this criterion, nephrotic FSGS is usually steroid-resistant and, if not controlled by more aggressive therapy, typically progresses to ESRD. DMP is commonly steroid-resistant but may slowly resolve. It is not clear to what extent remissions of DMP represent a delayed response to steroids or would have occurred without treatment. Biopsies showing a few globally obsolescent glomeruli or mild mesangial hypercellularity may be associated with greater difficulty in management but have been included in the broad category of MCD. Moreover, evolution of patterns in serial biopsies, variable steroid-responsiveness of FSGS and DMP, and progression of some cases of MCD to ESRD suggest common features in the three major categories. Among adults with idiopathic NS, FSGS is the most frequent biopsy pattern, followed by MN (which is rare in children) and then by MCD. In contrast to its pediatric counterpart, MCD in adults is less regularly and more slowly responsive to corticosteroids and in the elderly is more commonly associated with hypertension and renal failure. MCD in adults is less likely to relapse once remission is achieved. Adults with FSGS present less commonly with severe edema than do children with this lesion. Although children and adults with FSGS present similar challenges of resistance to therapy and loss of renal function, the more aggressive oral steroid regimens used by internists preclude strict comparisons between pediatric and adult series. There is insufficient information to support a systematic analysis of DMP in adults. Cytotoxic agents and cyclosporine have been used with varying success in children and adults with difficult cases of NS. In MCD, an alkylating agent can increase the likelihood and duration of remission. Cyclosporine can also improve control in MCD, but continued treatment is often needed to maintain remission. Significant control of steroid-resistant FSGS has not been achieved with limited courses of an alkylating agent or cyclosporine. Longer courses of either of these immunosuppressants, especially when combined with intermittent steroid administration, can produce more complete and/or more sustained remissions. However, cyclosporine nephrotoxicity is more severe in FSGS than in MCD and in steroid-resistant than in steroid-dependent NS, regardless of biopsy pattern. A protocol combining iv M-P pulses, alternate-day prednisone, and an alkylating agent in steroid-resistant pediatric FSGS has produced the highest percentage of sustained remissions with normal renal function, of all reported regimens. Controlled trials of this and other combined drug protocols are needed in children and adults.

If not aggressively treated, oral steroid-resistant (SRst) nephrotic focal segmental glomerulosclerosis (FSGS) is likely to progress to end-stage renal failure. Three observations challenge the conclusion of the International Study of Kidney Diseases in Children (ISKDC) that SRst FSGS is unresponsive to further immunosuppression: (1) The ISKDC definitions of response and relapse, which fit the patterns in minimal change disease, precluded appropriate recognition of partial or gradual responses. (2) In two ISKDC studies, a small number of children with FSGS in one case, and the use of a year of alternate-day prednisone as a control in the other, may have obscured the effects of cyclophosphamide. (3) Recent studies of more aggressive therapies have provided strong evidence of benefit. High-dose methylprednisolone infusion therapy, with alternate-day prednisone alone or with alternate-day prednisone plus an alkylating agent (the M-P/ triple therapy protocol) has achieved sustained, complete remissions with stable renal function in 66% of children with SRst FSGS, and near-complete resolution of proteinuria in another 9%. Cyclosporine (CsA) plus alternate-day prednisone has produced complete or near-complete remissions in 35% of similar cases. Whether or not controlled studies will confirm the apparently greater efficacy of the M-P/triple therapy protocol, the favorable outcomes with both the M-P and the CsA regimens support the conclusion that a conservative approach to SRst FSGS is no longer appropriate.

Most children with nephrotic syndrome do well, usually with multiple relapses and remissions. Some children require high doses of oral steroids to sustain a remission and develop significant steroid toxicity. These patients frequently can be managed with oral alkylating agents or with cyclosporine. A few nephrotic children to not respond to oral prednisone. The most common biopsy finding in steroid-resistant patients is focal segmental glomerulosclerosis. Many patients with this condition progress to chronic renal failure. Evidence suggests that the outcome is improved with either cyclosporine or with a protocol using pulse intravenous methylprednisolone and oral alkylating agents.

Extracorporeal membrane oxygenation (ECMO) is an effective treatment modality for the newborn with refractory hypoxemia. Oligohydramnios can be associated with congenital renal disease (CRD) and can result in respiratory insufficiency from pulmonary hypoplasia, delayed lung maturation, and persistent pulmonary hypertension of the newborn. In this retrospective study, the authors reviewed the outcome of four children with CRD who required ECMO in the neonatal period. Between October 1987 and December 1995, ECMO was used in four newborns with CRD and pulmonary hypoplasia unresponsive to maximal medical management. The causes of CRD were urinary obstruction (2), renal dysplasia (1), and vesicoureteral reflux (1). Neonatal survivors of ECMO with CRD had regular follow-up with a nephrologist, urologist, and pediatrician. Developmental history, assessment of renal function, and a nutritional evaluation were recorded on each visit. The follow-up period ranged from 6 months to 5 years. All patients with CRD were successfully weaned from ECMO. One child died, at 1 month of age, because of renal failure. The estimated glomerular filtration rates in the three survivors were 20, 24, and 60 mL/min/1.73 m2. Growth and development have been delayed in two patients. Based on the author's experience, ECMO may improve the survival of neonates with pulmonary hypoplasia and CRD. Factors associated with successful long-term outcome include (1) renal disease amenable to surgical correction, (2) aggressive nutritional support, and (3) a reliable social support system.

Unlabelled: Prednisone-resistant nephrotic syndrome (NS) due to focal segmental glomerulosclerosis (FSGS), the most common acquired disease requiring chronic dialysis and transplantation in children, has a low likelihood of response to alkylating agent therapy. This report summarizes the results of a 0.75-12.5 (average 6.33) year follow-up of 32 pediatric cases of prednisone-resistant FSGS treated with a regimen of high-dose intravenous methylprednisolone (M-P) and alternate-day prednisone, plus an alkylating agent in 25/32. On last followup: 21/32 were in remission [urine protein-to-creatinine ratios (Pru/Cru) < or = 0.2]; 3/32 had mild proteinuria (Pru/Cru > 0.2-0.5); 2/32 had moderate proteinuria (Pru/Cru > 0.5-1.9); and 6/32 remained nephrotic (Pru/Cru > or = 2.0). Of the incomplete or nonresponders; 3/11 progressed to end-stage renal failure; 5/11 had decreased creatinine clearances (CrCl): and 3/11 had persistent proteinuria with normal CrCl. All of the persistently nephrotic children, but none of the complete responders, developed decreased CrCl. All of the complete responders were able to stop treatment; four relapsed but responded well to retreatment., Conclusions: This regimen of methylprednisolone and alternate-day prednisone, with or without an alkylating agent, is effective in achieving sustained remissions and preserving normal renal function in the great majority of children with FSGS and prednisone-resistant NS.

Pulmonary hemorrhage may occur in patients with immune-mediated glomerulonephritis. This association can be seen in a variety of disorders including systemic lupus erythematosus, vasculitis, Wegener's granulomatosis, anaphylactoid purpura and Goodpasture's syndrome. Immune mechanisms, such as immune complexes and/or autoantibodies, play a role in the pathogenesis of pulmonary and glomerular injury. Acute pulmonary hemorrhage can lead to respiratory failure and has a high mortality. Therapy with immunosuppressive agents such as pulse methylprednisolone and cyclophosphamide will control the hemorrhage and improve pulmonary function in most cases.

Two cases of renal transplantation in pediatric patients with Laurence-Moon-Biedl syndrome are reported. Immunosuppressive therapy consisted of cyclosporine, prednisone and azathioprine. Renal function has been good but both patients developed morbid obesity.

The purpose of this report is to discuss the differential diagnosis of delayed puberty in the adolescent female with chronic renal failure. The appropriate therapy varies depending on the etiology of the delay. Frasier syndrome--chronic renal failure with true gonadal dysgenesis--should be considered in the diagnosis of a normal phenotypic female with end-stage renal disease and delayed puberty.

Objective: To determine the cause of absent sexual development in a 17-year-old girl with end-stage renal disease., Design: Case study., Participant: Seventeen-year-old girl with end-stage renal failure., Interventions: None., Measurements/main Results: The patient had phenotypically normal external female genitalia, müllerian duct hypoplasia, and no ovaries. Her serum gonadotropin levels were in the castrate range at baseline and after gonadotropin-releasing hormone stimulation. Her karyotype, in lymphocytes and cultured fibroblasts, was 46,XX. Analysis of genomic DNA, following polymerase chain reaction-amplication with oligonucleotide primers corresponding to the Y-encoded zinc finger protein ZFY and the testis-determining SRY gene, showed Y chromosome material in a male control but none in the patient., Conclusions: The results suggest a diagnosis of Frasier syndrome, a disorder characterized by true gonadal dysgenesis and end-stage renal disease occurring in normal phenotypic girls. Although previously reported only in individuals with a 46,XX karyotype, our studies indicate that Frasier syndrome may also occur in 46,XX girls. Delayed puberty is not uncommon in renal failure. This case illustrates the importance of measuring gonadotropin levels in teenage girls with delayed puberty and renal failure, particularly if the origin of the renal disease is obscure.

Fifty infants and children with acute renal failure were treated with acute peritoneal dialysis between 1987 and 1990. The patients were dialyzed using either a catheter introduced percutaneously over a guide-wire (n = 40) or a Tenckhoff catheter (n = 10). The cause of the acute renal failure was primary renal disease in 17 children, cardiac disease in 19, and trauma/sepsis in 14. Peritoneal dialysis succeeded in controlling metabolic abnormalities, improving fluid balance, and relieving the complications of uremia. The procedure had few major complications. Overall mortality was 50%, reflecting the serious nature of the underlying diseases. We conclude that acute peritoneal dialysis is a safe and effective treatment in most pediatric patients with acute renal failure. Our series of patients treated with acute peritoneal dialysis serves as a basis of comparison for the evaluation of new modalities of therapy in childhood acute renal failure.

We report two cases of symptomatic cholelithiasis in pediatric renal transplant recipients immunosuppressed with cyclosporine (CsA), prednisone and azathioprine. CsA was present in the bile and in the cholesterol gallstones of one patient. The diagnosis of cholelithiasis was established in both cases by abdominal ultrasound examination.