Mitochondrial transfer and implications for muscle function in idiopathic inflammatory myopathies

Impairment in cellular bioenergetics as either the cause, consequence, or major contributor of tissue damage has drawn increasing scientific curiosity across aging and chronic health conditions, with mitochondrial dysfunction emerging as a central mechanism in the pathogenesis of a variety of inflammatory and degenerative disorders. Beyond bioenergetics, mitochondria play critical regulatory roles in programmed cell death of dysfunctional/defective cells as well as in metabolite synthesis and metabolic signalling. Further, extra-cellular exposure to fragmentation of injured mitochondria is associated with incitement of systemic and organ-based inflammation. Thus, mitochondrial function has recently drawn intense, spectral scientific interest as an integral component across maladies.In muscle, mitochondrial dysfunction is clinically associated with atrophy and diminished endurance. Direct myo-histopathological evidence characterising loss of mitochondrial integrity as a hallmark of muscle compromise was first noticed in inclusion body myositis (IBM). This was followed by the discovery of multiple deletions in mitochondrial DNA in sarcopenia, IBM, and other inflammatory myopathies, like dermatomyositis. Though fraught with bioethical considerations, the transplant technology of mitochondrial transfer is swiftly gaining prominence in cellular biology and muscle physiology to remediate mitochondrial diminution and dysfunction. Assembling seminal works and recent developments, this review ventures into the rapidly evolving landscape of mitochondrial transfer, focusing on its implications on muscle function, and offers an integrated perspective on the potential roles of mitochondrial transfer and its implications for preserving and restoring muscle health. Presented here is a consolidated viewpoint on mitochondrial transfer in idiopathic inflammatory myopathies.

The Emerging Role of Mitochondrial Dysfunction in the Pathogenesis of Idiopathic Inflammatory Myopathies

Increasing evidence points towards mitochondria as crucial players in the initiation and progression of auto-immune and degenerative disorders, to which impaired cell metabolism is but a facet of the subjacent etiopathogenesis. This review aims to introduce the reader to essential concepts of mitochondrial abnormalities in idiopathic inflammatory myopathy (IIM), underscoring inclusion-body myositis and dermatomyositis. Far surpassing the initial simplistic view of being responsible for energy generation, mitochondria have gathered attention regarding their role in inflammatory processes, being able to fuel autoimmunity, as shown by the presence of anti-mitochondrial antibodies (AMAs) in up to 10% of IIM patients. As cellular respiration takes place, mitochondrial metabolites might help to shape the pro-inflammatory milieu in affected muscle, beyond generating reactive oxygen species, which are well-recognized inducers of damage-associated molecular patterns. A series of mitochondrial components might facilitate the sterile activation of pro-inflammatory cells and the production of several cytokines responsible for enhancing auto-immune responses. Marked variation in the mitochondrial genome has also been reported in IIM patients. As such, we summarize key historical and recent advances linking aberrations and instabilities of mitochondrial DNA to impaired muscle function. Besides discussing mitochondrial dysfunction as an essential part of IIM development, we also highlight possible associations between presence of AMAs and a particular phenotype of IIM, with its own characteristic clinical and radiological pattern. Finally, we present promising treatment approaches targeting mitochondria, while briefly discussing experimental models for gaining deeper insight into the disease process, and ultimately leading to novel drug development.

Obstetric profile of perinatal deaths on a capital of the Northeast of Brazil

Abstract Objectives: to analyze the obstetric and sociodemographic profile on perinatal deaths in Teresina the capital of Piauí, from data obtained from the Sistema de Informação de Mortalidade e Sistema de Informação de Nascidos Vivos (Brazilian Mortality Information System and Livebirth Information System). Methods: this is a retrospective cohort on perinatal deaths of mothers whose babies were born and resided in Teresina between 2010 and 2014. The analyzed variables were age and the mother´s schooling, gestational age, type of pregnancy (singleton or multiple), route of delivery (vaginal or cesarean), place of death (in and out hospital), time of death in relation to the delivery (prior, during or after), and birth weight. Results: the perinatal mortality coefficient (PMC) varied from 17.5 to 19.3 per 1,000 births. We found similarities in the sociodemographic profile and in the obstetric fetal and non-fetal deaths, both with a great incidence on 20 to 27 years-old mothers, vaginal delivery and singleton pregnancy. Low birth weight was positively related to early neonatal deaths. Conclusions: perinatal mortality presented a statistical correlation in gestational age, birth weight, and type of delivery. The PMC in our study was higher than other Brazilian capitals.

Emergency cricothyrotomy: temporary measure or definitive airway? A systematic review

Being a fast and safe method in the hands of well trained professionals in both prehospital and intrahospital care, Cricothyrotomy has been broadly recommended as the initial surgical airway in the scenario "can't intubate, can't ventilate", and is particularly useful when the obstruction level is above or at the glottis. Its prolonged permanence, however, is an endless source of controversy. In this review we evaluate the complications of cricothyrotomy and the need of its routine conversion to tracheotomy through a search on PubMed, LILACS and SciELO electronic databases with no restriction to the year or language of the publication. In total, we identified 791 references, retrieved 20 full text articles, and included nine studies in our review. The incidence of short-term complications ranged from zero to 31.6%, and the long-term complications, from zero to 7.86%. Subglotic stenosis was the main long-term reported complication, even though it was quite infrequent, occurring only in 2.9 to 5%. The frequency of conversion to tracheostomy varied from zero to 100%. Although a small frequency of long-term complications was found for emergency cricothyrotomy, the studies' low level of evidence does not allow the recommendation of routine use of cricothyrotomy as a secure definitive airway.

Primigravida with Bernard-Soulier Syndrome: a case report

Background

Bernard-Soulier Syndrome is a rare congenital bleeding disorder, mainly inherited in an autosomal recessive pattern. It is characterized by a genetic defect on one of the four genes encoding the subunits of the transmembrane protein complex GPIb-V-IX, physiologically expressed only in platelets. The exact phenotype varies widely from individual to individual depending on the particular mutation presented. Currently, there is no consensus about ideal management of affected pregnant women, in face of the scarcity of cases.

Case presentation

We report on a 28-year-old Black Brazilian primigravida who was referred to our maternity hospital, a tertiary care center, for decision about the most adequate mode of delivery. She was admitted with a platelet count of 43.000 plt/μL, and hemoglobin of 13.6 g/dL. Platelet transfusion was regarded as a necessary prophylactic measure prior to delivery. Ten units of random donor platelets were administered on the course of three days, after which the patient was submitted to an elective cesarean section delivery under general anesthesia at 40 weeks of gestational age. A healthy male baby with a normal birthweight of 3.615 kg was delivered. After the delivery, the mother’s state continued being assessed daily, with special attention taken to lochia and surgical wound healing. At one week postpartum, a complete blood count revealed a platelet count of 41.000 plt/μL, and hemoglobin of 13.3 g/dL. As there were no signs of neither evident nor occult hemorrhage, and surgical wound was healing accordingly, the patient was discharged, after being oriented about bleeding preventive measures.

Conclusion

The peripartum period is regarded as the most crucial moment of pregnancy in women with Bernard-Soulier Syndrome, hence the importance of a judiciously planned mode of delivery, and of careful prophylaxis against bleeding beforehand. Furthermore, absence of complications during the peripartum period does not predict how the woman will do subsequently. Strict vigilance is warranted at least until six weeks postpartum, due to the virtual risk of secondary postpartum hemorrhage.

Rio Grande do Norte, Brazil, voluntary bone marrow donors registry analysis

Objective: this study aimed to report the allele and haplotype frequencies of volunteer bone marrow donors (VBMD) from the state of Rio Grande do Norte (RN) who were enrolled in the Brazilian Volunteer Bone Marrow Donor Registry (REDOME). Methods: the sample comprised 12,973 VBMD who had their allele and haplotype frequencies calculated by Arlequin 3.5.1.2. A multivariate analysis of the data was obtained through a principal component analysis (PCA) and hierarchical cluster analysis (HCA) performed with SPSS 8.0. Results: the most frequent allelic group was HLA-A*02, followed by -DRB1*13, -DRB1*04, -DRB1*07, -B*44, -B*35, -A*24 and -DRB1*01. Of the 2,701 haplotypes observed, the three most frequent were HLA-A*01 B*08 DRB1*03 (1.62%), -A*29 B*44 DRB1*07 (1.56%) and -A*02 B*44 DRB1*04 (1.29%). These haplotypes were in linkage disequilibrium. RN allele and haplotype frequencies were very similar to those in other Brazilian states in which similar studies have been performed. The PCA revealed that RN is highly genetically similar to Caucasian populations, especially those from Iberian countries, which strongly influenced the state’s ethnic composition. Africans and Amerindians also influenced the RN population structure, to a lesser extent. Conclusion: the HCA reinforced the conclusion that, despite its highly admixed profile, the RN population is genetically similar to European and European-descended populations. The PCA also showed that RN cities do not contribute to the same extent to REDOME, with less populous cities being underrepresented, indicating the need to enroll more VBMD from these smaller cities to faithfully depict the state’s population structure in the database.

HLA-A, HLA-B and HLA-DRB1 haplotype frequencies in Piauí's volunteer bone marrow donors enrolled at the Brazilian registry

This study aimed to report the antigen and haplotype frequencies (HFs) of volunteer bone marrow donors (VBMDs) from the state of Piauí who were enrolled in the National Volunteer Bone Marrow Donor Registry (REDOME). The research subjects were 21,943 volunteer bone marrow donors, predominantly young adult women (53.3%). The most frequent allelic group was HLA-A2, followed by -DRB1*13, -DRB1*04, -DRB1*07, -B*15, -B∗35, -B*44, -A*24 and -A*03. Of the 2,704 haplotypes observed, the three most frequent haplotypes were A*29 B*44 DRB1*07 (1.45%), A*01 B*08 DRB1*03 (1.4%) and A*03 B*07 DRB1*15 (0.92%). These three haplotypes were in linkage disequilibrium. PCA showed that 98% of the VBMDs have HLA allele frequencies that are very similar to those from Teresina, the capital city of Piauí. According to the PCA results, these municipalities are distributed with a close proximity to Teresina, which in turn has a close genetic proximity to the Hispanic ethnicity, intermediate proximity to Caucasians and Africans and a distant kinship to Amerindians. The hierarchical proximity of the population of Piauí to the Portuguese and Hispanic populations to shows the strong influence of the latter on the former.