311 research outputs found

    In vivo confinement promotes collective migration of neural crest cells

    Get PDF
    Collective cell migration is fundamental throughout development and in many diseases. Spatial confinement using micropatterns has been shown to promote collective cell migration in vitro, but its effect in vivo remains unclear. Combining computational and experimental approaches, we show that the in vivo collective migration of neural crest cells (NCCs) depends on such confinement. We demonstrate that confinement may be imposed by the spatiotemporal distribution of a nonpermissive substrate provided by versican, an extracellular matrix molecule previously proposed to have contrasting roles: barrier or promoter of NCC migration. We resolve the controversy by demonstrating that versican works as an inhibitor of NCC migration and also acts as a guiding cue by forming exclusionary boundaries. Our model predicts an optimal number of cells in a given confinement width to allow for directional migration. This optimum coincides with the width of neural crest migratory streams analyzed across different species, proposing an explanation for the highly conserved nature of NCC streams during development

    The QUOVADIS Study: features of obese Italian patients seeking treatment at specialist centers

    Get PDF
    Obesity is a major risk factor for several chronic diseases, but the burden associated with it also extends to psychosocial areas and to perceived health status. In 1999 an observational study on healthrelated quality of life in obesity was planned. The study was entirely web-based. Case Report Forms and the individual items of 7 self-administered questionnaires were directly implemented on a general database via an extranet system from 25 Italian centers. By December 2001, after enrolment had stopped, the database included anthropometric, socioeconomic and clinical data of 1944 patients (78% females). Weightcycling was reported in over 80% of cases, overeating in 60-65%, structured physical activity in only 13- 15%. Several chronic illnesses were associated. Whereas the prevalence of diabetes and hypertension was related to the degree of obesity, hyperlipidemia and coronary heart disease did not increase further with increasing obesity. A disturbed psychological mood was twice more common in females. Concern for present health was the main reason for seeking treatment in both genders; concern for body appearance was more common in females. Male subjects were more frequently assigned to dietary counseling and physical exercise, whereas in females psychotherapy was more frequently considered. Various forms of behavioral approach were planned in approximately 50% of patients. Finally, very few patients were initially considered for pharmacological intervention or bariatric surgery. The study provides a comprehensive picture of Italian patients seeking treatment for obesity. Data on perceived health status, psychological well being, body image awareness, eating behavior disorders and psychopathological distress will provide clues to a comprehensive assessment of obesity, the effects of treatments and reasons for failure

    Visceral Leishmaniasis: Epidemiology, Diagnosis, and Treatment Regimens in Different Geographical Areas with a Focus on Pediatrics

    Get PDF
    Visceral Leishmaniasis (VL) is a vector-borne disease caused by an intracellular protozoa of the genus Leishmania that can be lethal if not treated. VL is caused by Leishmania donovani in Asia and in Eastern Africa, where the pathogens’ reservoir is represented by humans, and by Leishmania infantum in Latin America and in the Mediterranean area, where VL is a zoonotic disease and dog is the main reservoir. A part of the infected individuals become symptomatic, with irregular fever, splenomegaly, anemia or pancytopenia, and weakness, whereas others are asymptomatic. VL treatment has made progress in the last decades with the use of new drugs such as liposomal amphotericin B, and with new therapeutic regimens including monotherapy or a combination of drugs, aiming at shorter treatment duration and avoiding the development of resistance. However, the same treatment protocol may not be effective all over the world, due to differences in the infecting Leishmania species, so depending on the geographical area. This narrative review presents a comprehensive description of the clinical picture of VL, especially in children, the diagnostic approach, and some insight into the most used pharmacological therapies available worldwide

    Weight cycling in treatment-seeking obese persons: data from the QUOVADIS study

    Get PDF
    OBJECTIVE: To determine parameters of weight history useful for the assessment of weight cycling and their association with psychological distress and binge eating. DESIGN: Cross-sectional. SUBJECTS: A total of 1889 treatment-seeking obese subjects, enrolled by 25 Italian centers (78% female subject), aged 20–65 y (median 45); 1691 reported previous efforts to lose weight (median age of first dieting, 30 y). MEASUREMENTS: The number of yearly attempts to lose weight, weight gain since age 20 y, cumulative weight loss and gain were checked by a predefined structured interview. Psychological distress was tested by means of Symptom Check-List 90 (SCL-90), Binge Eating Scale (BES) and Three Factor Eating Questionnaire (TFEQ). RESULTS: Differences in anthropometric, clinical and psychological parameters were observed in relation to previous attempts to lose weight. Patients in the upper quartile of parameters of weight history were considered weight cyclers. In multivariate logistic regression analysis, after correction for age, sex and BMI, a high BES score was the only factor systematically associated with a high frequency of dieting (OR, 1.70; 95% confidence interval, 1.22–2.36; P¼0.022), with higher cumulative weight loss (1.42; 1.12–1.80; P¼0.003) and cumulative weight gain (1.38; 1.06–1.79; P¼0.017). However, the sensitivity, specificity and positive predictive value of a high BES score were very low to detect cyclers. Weight cycling did not carry a higher risk of complicating diseases. CONCLUSIONS: Weight cycling is associated with psychological distress, and binge eating independently increases the risk, but cannot be used to predict cycling. Also, obese patients who do not experience overeating as a loss of control discontinue treatment or regain weight following therapy

    Mutations in TIMM50 compromise cell survival in OxPhos-dependent metabolic conditions

    Get PDF
    TIMM50 is an essential component of the TIM23 complex, the mitochondrial inner membrane machinery that imports cytosolic proteins containing a mitochondrial targeting presequence into the mitochondrial inner compartment. Whole exome sequencing (WES) identified compound heterozygous pathogenic mutations in TIMM50 in an infant patient with rapidly progressive, severe encephalopathy. Patient fibroblasts presented low levels of TIMM50 and other components of the TIM23 complex, lower mitochondrial membrane potential, and impaired TIM23-dependent protein import. As a consequence, steady-state levels of several components of mitochondrial respiratory chain were decreased, resulting in decreased respiration and increased ROS production. Growth of patient fibroblasts in galactose shifted energy production metabolism toward oxidative phosphorylation (OxPhos), producing an apparent improvement in most of the above features but also increased apoptosis. Complementation of patient fibroblasts with TIMM50 improved or restored these features to control levels. Moreover, RNASEH1 and ISCU mutant fibroblasts only shared a few of these features with TIMM50 mutant fibroblasts. Our results indicate that mutations in TIMM50 cause multiple mitochondrial bioenergetic dysfunction and that functional TIMM50 is essential for cell survival in OxPhos-dependent conditions

    Species-specific pace of development is associated with differences in protein stability

    Get PDF
    Although many molecular mechanisms controlling developmental processes are evolutionarily conserved, the speed at which the embryo develops can vary substantially between species. For example, the same genetic program, comprising sequential changes in transcriptional states, governs the differentiation of motor neurons in mouse and human, but the tempo at which it operates differs between species. Using in vitro directed differentiation of embryonic stem cells to motor neurons, we show that the program runs more than twice as fast in mouse as in human. This is not due to differences in signaling, nor the genomic sequence of genes or their regulatory elements. Instead, there is an approximately two-fold increase in protein stability and cell cycle duration in human cells compared with mouse cells. This can account for the slower pace of human development and suggests that differences in protein turnover play a role in interspecies differences in developmental tempo

    Mutations of the Mitochondrial-tRNA Modifier MTO1 Cause Hypertrophic Cardiomyopathy and Lactic Acidosis

    Get PDF
    Dysfunction of mitochondrial respiration is an increasingly recognized cause of isolated hypertrophic cardiomyopathy. To gain insight into the genetic origin of this condition, we used next-generation exome sequencing to identify mutations in MTO1, which encodes mitochondrial translation optimization 1. Two affected siblings carried a maternal c.1858dup (p.Arg620Lysfs∗8) frameshift and a paternal c.1282G>A (p.Ala428Thr) missense mutation. A third unrelated individual was homozygous for the latter change. In both humans and yeast, MTO1 increases the accuracy and efficiency of mtDNA translation by catalyzing the 5-carboxymethylaminomethylation of the wobble uridine base in three mitochondrial tRNAs (mt-tRNAs). Accordingly, mutant muscle and fibroblasts showed variably combined reduction in mtDNA-dependent respiratory chain activities. Reduced respiration in mutant cells was corrected by expressing a wild-type MTO1 cDNA. Conversely, defective respiration of a yeast mto1Δ strain failed to be corrected by an Mto1Pro622∗ variant, equivalent to human MTO1Arg620Lysfs∗8, whereas incomplete correction was achieved by an Mto1Ala431Thr variant, corresponding to human MTO1Ala428Thr. The respiratory yeast phenotype was dramatically worsened in stress conditions and in the presence of a paromomycin-resistant (PR) mitochondrial rRNA mutation. Lastly, in vivo mtDNA translation was impaired in the mutant yeast strains

    Synergistic cytotoxic effects of bortezomib and CK2 inhibitor CX-4945 in acute lymphoblastic leukemia: turning offthe prosurvival ER chaperone BIP/Grp78 and turning on the proapoptotic NF-κB

    Get PDF
    The proteasome inhibitor bortezomib is a new targeted treatment option for refractory or relapsed acute lymphoblastic leukemia (ALL) patients. However, a limited efficacy of bortezomib alone has been reported. A terminal pro-apoptotic endoplasmic reticulum (ER) stress/unfolded protein response (UPR) is one of the several mechanisms of bortezomib-induced apoptosis. Recently, it has been documented that UPR disruption could be considered a selective anti-leukemia therapy. CX- 4945, a potent casein kinase (CK) 2 inhibitor, has been found to induce apoptotic cell death in T-ALL preclinical models, via perturbation of ER/UPR pathway. In this study, we analyzed in T- and B-ALL preclinical settings, the molecular mechanisms of synergistic apoptotic effects observed after bortezomib/CX-4945 combined treatment. We demonstrated that, adding CX-4945 after bortezomib treatment, prevented leukemic cells from engaging a functional UPR in order to buffer the bortezomibmediated proteotoxic stress in ER lumen. We documented that the combined treatment decreased pro-survival ER chaperon BIP/Grp78 expression, via reduction of chaperoning activity of Hsp90. Bortezomib/CX-4945 treatment inhibited NF-κB signaling in T-ALL cell lines and primary cells from T-ALL patients, but, intriguingly, in B-ALL cells the drug combination activated NF-κB p65 pro-apoptotic functions. In fact in B-cells, the combined treatment induced p65-HDAC1 association with consequent repression of the anti-apoptotic target genes, Bcl-xL and XIAP. Exposure to NEMO (IKKγ)-binding domain inhibitor peptide reduced the cytotoxic effects of bortezomib/CX-4945 treatment. Overall, our findings demonstrated that CK2 inhibition could be useful in combination with bortezomib as a novel therapeutic strategy in both T- and B-ALL
    • …
    corecore