Pediatric Ventilation Skills by Non-Healthcare Students: Effectiveness, Self-Perception, and Preference.

Since a great number of infant cardiopulmonary arrests occur outside of the hospital, it is crucial to train laypersons in cardiopulmonary resuscitation techniques, especially those professionals that will work with infants and children. The main objective of this study was to evaluate the efectiveness of ventilations performed by professional training students. The secondary objective was to analyze the preference between different ventilation and chest-compression methods. The sample consisted of 32 professional training students, 15 preschool students, and 17 physical education students. The activity was conducted separately for each group, and we provided a 10 min theoretical training about infant basic life support followed by a 45 min practical training using a Laerdal Little Anne QCPR CPR manikin. A practical test in pairs was organized to record the ventilation as performed by the participants, establishing the difference between the efficacious and the non-efficacious ones. Furthermore, we handed out a survey before and after training to evaluate their knowledge. More than 90% of the students completely agreed with the importance of learning cardiopulmonary resuscitation techniques for their professional future. More than half of the sample considered that they perform the rescue breathings with the mouth-to-mouth method better. We observed that through mouth-to-mouth-nose ventilations, the number of effective ventilations was significantly higher than the effective ventilations provided by a self-inflating bag and mask (EffectiveMtoMN 6.42 ± 4.27 vs. EffectiveMask 4.75 ± 3.63 (p = 0.007)), which was the preferred method. In terms of the compression method, hands encircling the chest was preferred by more than 85% of students. Mouth-to-mouth nose ventilation is more efficient than bag-face-mask ventilation in CPR as performed by professional training and physical activity students. This fact must be considered to provide higher-quality training sessions to professional training students.

In vitro biological-to-immunological ratio of serum gonadotropins throughout male puberty in children with insulin-dependent diabetes mellitus.

Information on the impact of prolonged deficient glycemic control in the quality of the gonadotropin signal delivered by the pituitary gland during puberty in children with insulin-dependent diabetes mellitus (IDDM) is scarce. In the present study, we examined the impact of deficient glycemic control on bioactive LH and FSH concentrations and their corresponding biological-to-immunological (B:I) ratio in boys with poorly controlled, but systemically uncomplicated IDDM. Dual control groups comprising patients with well-controlled IDDM and healthy boys of comparable age and body mass index were included for appropriate comparisons within and between each pubertal stage. Patients with poorly controlled and well-controlled IDDM exhibited serum bioactive FSH levels and B:I FSH ratio similar to those showed by the healthy control group. In contrast, in early and mid-pubertal boys with poorly controlled IDDM bioactive LH levels were normal, but its B:I LH relationship was significantly (P < 0.05) decreased. This attenuation in the quality of the LH signal did not affect total serum T concentrations, and apparently, progression of puberty. Long-standing uncontrolled diabetes and the consequent metabolic disturbances and/or complications may aggravate the reproductive axis dysfunction and eventually provoke pubertal arrest.

Beyond the signal sequence: protein routing in health and disease.

Receptors, hormones, enzymes, ion channels, and structural components of the cell are created by the act of protein synthesis. Synthesis alone is insufficient for proper function, of course; for a cell to operate effectively, its components must be correctly compartmentalized. The mechanism by which proteins maintain the fidelity of localization warrants attention in light of the large number of different molecules that must be routed to distinct subcellular loci, the potential for error, and resultant disease. This review summarizes diseases known to have etiologies based on defective protein folding or failure of the cell's quality control apparatus and presents approaches for therapeutic intervention.

A Galphas mutation (D229S) differentially effects gonadotropin-releasing hormone receptor regulation by RGS10, RGS3 and RGS3T.

Regulators of G protein signaling (RGS) act as GTPase-activating proteins for Galpha(i) and for Galpha(q/11). There is recent evidence for interaction of RGS proteins with Galpha(s), and substitution of Ser for Asp(229) in RGS proteins enhances interactions with G proteins. Site-directed mutagenesis of Asp(229) was used to assess the effect of this site on the gonadotropin-releasing hormone receptor (GnRHR)-Galpha(s) mediated signaling in the absence or presence of over-expressed RGS3, RGS10 or a truncated form of RGS3 (RGS3T). We observed increased cAMP release with the mutant Galpha(s)(D(229)S) compared to wt Galpha(s) when GGH(3) cells (GH(3) cells stably expressing the GnRH receptor) were stimulated with a GnRH agonist. In the presence of RGS3, we did not observe any difference in cAMP release with wt Galpha(s) or with Galpha(s)(D(229)S) compared to control values; in the presence of RGS3T there was an increase of cAMP release with wt Galpha(s) compared to the control but there was no difference between the Galpha(s)(D(229)S) and the control values. When cells co-expressed wt Galpha(s) and RGS10, there was a significant increase of cAMP release compared with cells co-expressing wt Galpha(s) and Lac Z. Cells co-expressing Galpha(s)(D(229)S) and RGS10 showed a significant increase of cAMP release compared to control cells. These results indicate differential regulation of the GnRHR-Galpha(s) mediated signaling by a single mutation in Galpha(s) in the presence of RGS10 and RGS3T, but not with RGS3. This is the first report of an effect of the Galpha(s)(D(229)S) mutation on G protein-coupled receptor-mediated activation.

Regulation of the gonadotropin-releasing hormone receptor (GnRHR) by RGS proteins: role of the GnRHR carboxyl-terminus.

The cytoplasmic carboxyl-terminus of G-protein coupled receptors (GPCRs), absent in the mammalian gonadotropin-releasing hormone receptor (GnRHR), plays an important role in receptor expression, desensitization, internalization and efficiency of coupling to G proteins. Regulators of G protein signaling (RGS) likewise are involved in regulating GPCR-G protein mediated responses and can regulate transcription of other genes. In this study, we evaluate differential expression, ligand binding and effector coupling of the rat GnRHR (rGnRHR) and a chimera of rGnRHR with the pre-mammalian carboxyl domain (rGnRHR-C-tail). Membrane expression of the chimeric receptor and G(q)alpha and G(s)alpha-mediated signaling was increased 2- and 1.5-fold, respectively by RGS10, while RGS3 did not interfere with rGnRHR and rGnRHR-C-tail cell surface expression in spite of negatively regulating GnRH-stimulated G(q)alpha-mediated signaling by both receptors. The rGnRHR and rGnRHR-C-tail showed similar internalization rates in the presence of either RGS protein, indicating that the modification of rGnRHR expression and regulation in the presence of a carboxyl-terminus by RGS10 was not caused by alteration of the internalization rate. The observations in this study implicate the carboxyl domain of the receptor as a site of interaction for RGS10, but not RGS3. This is the first evidence of an altered cell surface expression and regulation of the GnRHR bearing a carboxyl-terminus by RGS proteins.

Regulation of RGS3 and RGS10 palmitoylation by GnRH.

Regulators of G protein signaling (RGS) play a pivotal role in cellular signal transduction. RGS3 or RGS10 were overexpressed in GGH(3) cells [GH(3) cells stably expressing the GnRH receptor (GnRHR)]. Responsiveness to a GnRH agonist was assessed because RGS proteins attenuate production of inositol phosphates (IP) and/or cAMP, molecules believed to be involved in GnRH signaling. In addition, site-directed mutagenesis of a potentially palmitoylated Cys(60) residue of RGS10 was used to assess the significance of this site. We observed maximum inhibition of GnRH-stimulated IP responses by RGS3 and by the conserved domain of RGS10 at both 48 and 72 h after transfection, indicating their involvement in G(q)alpha mediated signaling. Significantly diminished cAMP production was observed at all times when cells overexpressed the conserved domain of RGS10; no effect was observed with RGS3 on G(s)alpha-mediated signaling. Palmitic acid incorporation into RGS3 was dependent on agonist occupancy of GnRHR, whereas palmitoylation of RGS10 was constitutive. Mutation of the conserved Cys(60) residue of RGS10 obviated its negative regulatory action on GnRH-stimulated responses, indicating that this site is crucial for its activity on this system. This study is the first demonstration of a role for palmitoylation of this conserved Cys(60) in mammalian G protein signaling.