Distribution of plasma membrane Ca2+ pump activity in normal human red blood cells

The plasma membrane calcium pump (PMCA) is the only active Ca2+ transporter in human red blood cells (RBCs). Previous measurements of maximal Ca2+ extrusion rates (Vmax) reported only mean values in the RBC population. Despite early evidence for differences in Ca2+ extrusion capacity among RBCs, the precise Vmax distribution remained unknown. It was important to characterize this distribution to assess the range and modality (uni- or multimodal) of PMCA Vmax variation and the likelihood of RBCs with elevated [Ca2+]i in the circulation participating in physiologic and pathologic processes. We report here the application of a new method to investigate the detailed distribution of PMCA Vmax activity in RBCs. The migrating profile of osmotic lysis curves was used to identify and quantify the fraction of cells that extrude a uniform Ca2+ load at different rates. The results revealed that RBCs from single donors have large variations in PMCA activity that follow a unimodal, broad distribution pattern consistently skewed toward higher Vmax values, suggesting an excess of cells with Vmax higher than the mean value. The method applied may provide a way of evaluating whether the observed variation in PMCA Vmax is related to cell age.     

Human mesenchymal stem cells alter antigen-presenting cell maturation and induce T-cell unresponsiveness

Infusion of either embryonic or mesenchymal stem cells prolongs the survival of organ transplants derived from stem cell donors and prevents graft-versus-host-disease (GVHD). An in-depth mechanistic understanding of this tolerization phenomenon could lead to novel cell-based therapies for transplantation. Here we demonstrate that while human mesenchymal stem cells (hMSCs) can promote superantigen-induced activation of purified T cells, addition of antigen-presenting cells (APCs; either monocytes or dendritic cells) to the cultures inhibits the T-cell responses. This contact- and dose-dependent inhibition is accompanied by secretion of large quantities of interleukin (IL)-10 and aberrant APC maturation, which can be partially overridden by the addition of factors that promote APC maturation (ie, lipopolysaccharide [LPS] or anti-CD40 monoclonal antibody [mAb]). Thus, our data support an immunoregulatory mechanism wherein hMSCs inhibit T cells indirectly by contact-dependent induction of regulatory APCs with T-cell-suppressive properties. Our data may reveal a physiologic phenomenon whereby the development of a distinct APC population is regulated by the tissue's cellular microenvironment.     

Institutional Blood Glucose Monitoring System for Hospitalized Patients: An Integral Component of the Inpatient Glucose Control Program

Background

The ability to measure patient blood glucose levels at bedside in hospitalized patients and to transmit those values to a central database enables and facilitates glucose control and follow-up and is an integral component in the care of the hospitalized diabetic patient.

Objective

The goal of this study was to evaluate the performance of an institutional glucometer employed in the framework of the Program for the Treatment of the Hospitalized Diabetic Patient (PTHDP) at E. Wolfson Medical Center, Holon, Israel.

Methods

As part of the program to facilitate glucose control in hospitalized diabetic patients, an institutional glucometer was employed that permits uploading of data from stands located in each inpatient department and downloading of that data to a central hospital-wide database. Blood glucose values from hospitalized diabetic patients were collected from August 2007 to October 2008. The inpatient glucose control program was introduced gradually beginning January 2008.

Results

During the follow-up period, more than 150,000 blood glucose measures were taken. Mean glucose was 195.7 ± 99.12 mg/dl during the follow-up period. Blood glucose values declined from 206 ± 105 prior to PTHDP (August 2007–December 2007) to 186 ± 92 after its inception (January 2008–October 2008). The decline was associated significantly with time (r = 0.11, p < 0.0001). The prevalence of blood glucose values lower than 60 mg/dl was 1.48% [95% confidence interval (CI) 0.36%] prior to vs 1.55% (95% CI 0.37%) following implementation of the PTHDP. Concomitantly, a significant increase in the proportion of blood glucose values between 80 and 200 mg/dl was observed, from 55.5% prior to program initiation vs 61.6% after program initiation (p < 0.0001).

Conclusions

The present study was designed to observe changes in institution-wide glucose values following implementation of the PTHDP. Information was extracted from the glucometer system itself. Because the aforementioned study was not a clinical trial, we cannot rule out that factors other than introduction of the program could explain some of the variability observed. With these limitations in mind, it nevertheless appears that the PTHDP, of which the institutional glucometer is an integral, essential component, was associated with improved blood glucose values in the hospitalized diabetic patient.     

Laminin-111 Restores Regenerative Capacity in a Mouse Model for α7 Integrin Congenital Myopathy

Mutations in the α7 integrin gene cause congenital myopathy characterized by delayed developmental milestones and impaired mobility. Previous studies in dystrophic mice suggest the α7β1 integrin may be critical for muscle repair. To investigate the role that α7β1 integrin plays in muscle regeneration, cardiotoxin was used to induce damage in the tibialis anterior muscle of α7 integrin-null mice. Unlike wild-type muscle, which responded rapidly to repair damaged myofibers, α7 integrin-deficient muscle exhibited defective regeneration. Analysis of Pax7 and MyoD expression revealed a profound delay in satellite cell activation after cardiotoxin treatment in α7 integrin-null animals when compared with wild type. We have recently demonstrated that the muscle of α7 integrin-null mice exhibits reduced laminin-α2 expression. To test the hypothesis that loss of laminin contributes to the defective muscle regeneration phenotype observed in α7 integrin-null mice, mouse laminin-111 (α1, β1, γ1) protein was injected into the tibialis anterior muscle 3 days before cardiotoxin-induced injury. The injected laminin-111 protein infiltrated the entire muscle and restored myogenic repair and muscle regeneration in α7 integrin-null muscle to wild-type levels. Our data demonstrate a critical role for a laminin-rich microenvironment in muscle repair and suggest laminin- 111 protein may serve as an unexpected and novel therapeutic agent for patients with congenital myopathies.     

Neuregulin promotes autophagic cell death of prostate cancer cells

BACKGROUND: Prostate cancer is one of the most frequently diagnosed cancers in males. Autocrine/paracrine growth factors for the epidermal growth factor receptor (EGFR) have been identified in prostate tumors suggesting a role for EGFR in the progression of prostate cancer. The androgen-dependent prostate cancer cell line, LNCaP, expresses the EGFR as well as two additional members of the family; ErbB-2 and ErbB-3, which can be activated by neuregulin (NRG) isoforms. The effect of ErbB ligands on the viability of LNCaP cells was studied. METHODS: In the present study, we examined the effect of NRG on LNCaP cell growth and survival in the absence of androgen mimetic by the MTT assay, FACS analysis, nuclei staining, and Western blotting. RESULTS: Our results demonstrate that NRG activates ErbB-2/ErbB-3 heterodimers and induces cell death of LNCaP cells. By contrast, EGF activates ErbB-1/ErbB-1 or ErbB-1/ErbB-2 dimers and induces cell growth and survival. Interestingly, LNCaP cells treated with PI3K inhibitor underwent cell death but cells treated with both NRG and PI3K inhibitor survived as the control cells, indicating that the PI3K pathway may mediate NRG-induced cell death. NRG-induced cell death was not inhibited by the broad-spectrum caspases inhibitor, benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (Z-VAD-FMK). However, NRG-induced cell death was inhibited by type II cell death inhibitor, 3-methyladenine. CONCLUSIONS: These results suggest that NRG induces type II cell death of LNCaP cells through PI3K-dependent pathway.     

M1 muscarinic agonists can modulate some of the hallmarks in Alzheimer’s disease

M₁ muscarinic receptors (M₁ mAChRs) play a role in an apparent linkage of three major hallmarks of Alzheimer’s disease (AD): β-amyloid (Aβ) peptide; tau hyperphosphorylation and paired helical filaments (PHFs); and loss of cholinergic function conducive to cognitive impairments. We evaluated the M₁ muscarinic agonists AF102B (Cevimeline, EVOXAC?: prescribed for Sjøgren’s syndrome), AF150(S), and AF267B on some of these hallmarks of AD. Activation of M₁ mAChRs with these agonists leads, inter alia, to enhanced secretion of amyloid precursor protein (α-APP), (via α-secretase activation), to decreased Aβ (via γ-secretase inhibition), and to inhibition of Aβ- and/or oxidative stress-induced cell death. In several animal models mimicking different aspects of AD, these drugs restored cognitive impairments, and in select cases induced a decrease in brain Aβ elevation, with a high safety margin, following po administration. Notably, in mice with small hippocampi, unlike rivastigmine and nicotine, AF150(S) and AF267B restored cognitive impairments also on escape latency in a Morris water maze paradigm, in reversal learning. Studies from other labs showed that AF102B and talsaclidine (another M₁ agonist) decreased cerbrospinal fluid (CSF) Aβ in AD patients following chronic treatment, being the first reported drugs with such a profile. The clinical significance of these studies remains to be elucidated, yet based on in vivo (rabbits) and in vitro studies (cell cultures), our M₁ agonists can decrease brain Aβ, owing to a novel and dual complementary effect (e.g., inhibition of γ-secretase and activation of α-secretase). Remarkably, although M₁ agonists can decrease CSF Aβ in AD patients, an increased AD-type pathology in Parkinson’s disease was recently been associated with chronic antimuscarinic treatment. In another aspect, these agonists decreased tau hyperphosphorylation in vitro and in vivo. Notably, nicotinic agonists or cholinesterase inhibitors increased tau hyperphosphorylation. In summary, the M₁ agonists tested are effective on cognition and behavior and show unique disease-modifying properties owing to beneficial effects on major hallmarks of AD. This may place such drugs in the first line of modern AD therapies (e.g., β- or γ-secretase inhibitors, vaccines against Aβ, statins, and inhibitors of tau hyperphosphorylation).     

MOTHERISK ROUNDS: The Fetal Safety of Fluoxetine: A Systematic Review and Meta-Analysis

ObjectiveFluoxetine is the selective serotonin reuptake inhibitor (SSRI) with the longest clinical use. Published reports regarding its fetal safety are contradictory. We aimed to establish the fetal safety of the drug.MethodWe performed a systematic review of the literature, searching PubMed, Medline, and Embase from inception to August 31, 2012, for cohort and case–control studies in which women were exposed to fluoxetine during the first trimester and compared outcomes with those of unexposed control subjects.ResultsTwenty-one studies met the inclusion criteria. The odds ratio for major malformations associated with maternal fluoxetine use in cohort studies was 1.12 (95% CI 0.98 to 1.28). The studies included were homogeneous. Fifteen cohort studies evaluated cardiac malformations and yielded an overall odds ratio of 1.6 (95% CI 1.31 to 1.95). These studies also were homogeneous. In contrast, two case–control studies assessing cardiac malformations yielded a combined odds ratio of 0.63 (95% CI 0.39 to 1.03).ConclusionThe apparent increased risk of fetal cardiac malformations associated with maternal use of fluoxetine has recently been shown also in depressed women who deferred SSRI therapy in pregnancy, and therefore most probably reflects an ascertainment bias. Overall, women who are treated with fluoxetine during the first trimester of pregnancy do not appear to have an increased risk of major fetal malformations.     

The contribution of bibliotherapy to the counseling of aggressive boys

Abstract

This study investigated the contribution of bibliotherapy to the counseling of aggressive boys by novice counselors in Israel. Counseling for all children was provided within an integrative model (Hill, 2005); bibliotherapy was added as adjunct to the counseling process only in 1 group. Boys from 24 classrooms (3 per class) were randomly assigned to 1 of 3 conditions: integrative counseling (IC), integrative counseling plus bibliotherapy (ICB), or no counseling. Results of the comparison among the 3 conditions indicated reduced aggression and increased empathy in both IC and ICB conditions compared with the control condition. A difference between IC and ICB conditions was found for empathy and therapist satisfaction, with higher gains in ICB. In the ICB condition, boys also demonstrated higher stages of change (Prochaska, 1999) and had higher frequencies of insight and therapeutic change (Hill, 2005) compared with boys in the IC condition.

Zusammenfassung

Der Beitrag von Bibliotherapie zur Beratung von aggressiven Jungen

Diese Studie untersuchte den Beitrag von Bibliotherapie zur Beratung von aggressiven Jungen durch Beratungsanfänger in Israel. Die Beratung aller Kinder wurde innerhalb der Anwendung eines integrativen Models (Hill, 2005) gegeben. Die Bibliotherapie wurde zusätzlich zum Beratungsprozess nur bei der Gruppe 1 angewendet. Jungen von 24 Klassen (3 aus jeder Klasse) wurden dem Zufall nach einer von drei Bedingungen zugewiesen: Integrative Beratungen (integrative counseling [IC]), integrative Beratungen plus Bibliotherapie (ICB), oder keine Beratung. Die Ergebnisse zum Vergleich zwischen den drei Bedingungen wiesen einen Rückgang der Aggressionen und einen Anstieg von Empathie unter der IC und der ICB Bedingung im Vergleich zur Kontrollgruppe auf. Ein Unterschied zwischen der IC und der ICB Bedingung wurde für Empathie und Therapeutenzufriedenheit gefunden, mit größeren Anstiegswerten für ICB. Unter der ICB Bedingung zeigten die Jungen auch höhere Veränderungsniveaus (Prochaska, 1999). Im Vergleich zu den Jungen unter der IC Bedingung zeigten sie häufiger Einsicht und therapeutische Veränderung (Hill, 2005).

Résumé

La contribution de la bibliothérapie dans le counseling de garçons agressifs

Cette étude a investigué la contribution de la bibliothérapie dans le counseling de garçons agressifs par des conseillers novices en Israël. Le counseling pour tous les enfants était procuré dans le cadre d'un modèle intégratif (Hill, 2005)?; la bibliothérapie était rajoutée comme un supplément au processus de counseling dans un seul groupe. Des garçons de 24 classes (3 par classe) étaient attribués au hasard à 1 de 3 conditions?: counseling intégratif (CI), counseling intégratif plus bibliothérapie (CIB), pas de counseling. Les résultats comparatifs entre les 3 conditions montrent une agression diminuée et une empathie augmentée dans les conditions CI et CIB par rapport à la condition contrôle. Une différence entre CI et CIB se trouvait pour l'empathie et la satisfaction des thérapeutes, avec des gains supérieurs en CIB. Dans la condition CIB,les garçons montraient aussi des niveaux supérieurs de changement (Prochaska, 1999) et ils avaient plus d'insight et de changement thérapeutique (Hill, 2005) en comparaison avec les garçons de la condition CI..

Resumen

Contribución de la biblioterapia al counseling de jóvenes agresivos

Este estudio investigó la contribución de la biblioterapia al counseling de chicos agresivos realizado por consultores novicios en Israel. Se suministró counseling a todos los chicos dentro de un modelo integrativo (Hill, 2005), y se agregó biblioterapia al proceso en un grupo. En 24 aulas, tres chicos por aula se asignaron al azar a 1 de 3 condiciones: counseling integrativo (IC), counseling integrativo más biblioterapia (ICB) o ningún counseling. Los resultados de la comparación entre las tres condiciones fueron: agresión reducida y aumento de empatía tanto en la IC como en la ICB comparadas con la condición control. Se encontró una diferencia entre la IC y la ICB para la empatía y la satisfacción del terapeuta, con mayores mejorías en la ICB. En esta, los chicos demostraron también niveles mayores de cambio (Prochaska, 1999), mayores frecuencias de insight y de cambio terapéutico (Hill, 2005) en comparación con chicos de la condición IC.

Resumo

As contribuições da biblioterapia para o aconselhamento de rapazes agressivos

Este estudo investigou a contribuição da biblioterapia para o aconselhamento de rapazes agressivos por conselheiros principiantes em Israel. O aconselhamento para todas as crianças foi baseado no modelo integrativo (Hill, 2005); tendo-se adicionado a biblioterapia ao processo de aconselhamento apenas num grupo. Os rapazes de 24 salas (3 de cada sala) foram aleatoriamente distribuídos para uma das três condições: aconselhamento integrativo (IC), aconselhamento integrativo mais biblioterapia (ICB), ou nenhum aconselhamento. Os resultados da comparação entre as 3 condições indicaram redução da agressão e aumento da empatia nas condições de IC e ICB quando comparadas com a condição de controlo. Foi encontrada uma diferença entre as condições de IC e ICB em termos da empatia e satisfação do terapeuta, com maiores ganhos na ICB. Na condição ICB, os rapazes demonstraram maiores estádios de mudança (Prochaska, 1999) e tinham maiores frequências de insight e mudança terapêutica (Hill, 2005) comparados com os rapazes da condição de IC.

Sommario

Il contributo della biblioterapia al counseling di ragazzi aggressivi

Questo studio ha indagato il contributo della biblioterapia al counseling dei ragazzi aggressivi effettuato da counselors principianti in Israele.

Il counseling per tutti i bambini è stato fornito all'interno di un modello integrato (Hill, 2005); la biblioterapia è stata fatta come aggiunta al processo di counseling solo in un gruppo.

I ragazzi di 24 classi (3 per classi) sono stati assegnati casualmente ad 1 di 3 condizioni: counseling integrato (IC), counseling integrato più biblioterapia (ICB) o assenza di counseling.

I risultati del confronto tra le 3 condizioni hanno indicato riduzione di aggressività e incremento di empatia sia nella condizione IC che nella ICB, rispetto alla condizione di controllo. Una differenza tra le condizioni IC e ICB è stata trovata nell'empatia e nella soddisfazione dei terapeuti, con migliori risultati nell'ICB. Nella condizione ICB, inoltre, i ragazzi hanno mostrato più alti stati di cambiamento (Prochaska, 1999) ed avevano più alte frequenze di insight e cambiamento terapeutico (Hill, 2005) rispetto ai ragazzi nella condizione IC.

Abstract

     

Tyrphostins suppress the growth of psoriatic keratinocytes

Abstract Tyrosine kinase inhibitors of the tyrphostin family which block EGF receptor kinase are reported to arrest the growth of psoriatic keratinocytes in vitro. Three tyrphostins with the potency ratio AG555 >> AG18 >> AG814 were found to arrest growth with no adverse cytotoxic effects. The potency ratio to inhibit keratinocyte proliferation follows their potency to inhibit EGF receptor kinase activity in vitro. These compounds represent novel leads for the therapy of psoriasis.