Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Mitochondrial physiology

As the knowledge base and importance of mitochondrial physiology to evolution, health and disease expands, the necessity for harmonizing the terminology concerning mitochondrial respiratory states and rates has become increasingly apparent. The chemiosmotic theory establishes the mechanism of energy transformation and coupling in oxidative phosphorylation. The unifying concept of the protonmotive force provides the framework for developing a consistent theoretical foundation of mitochondrial physiology and bioenergetics. We follow the latest SI guidelines and those of the International Union of Pure and Applied Chemistry (IUPAC) on terminology in physical chemistry, extended by considerations of open systems and thermodynamics of irreversible processes. The concept-driven constructive terminology incorporates the meaning of each quantity and aligns concepts and symbols with the nomenclature of classical bioenergetics. We endeavour to provide a balanced view of mitochondrial respiratory control and a critical discussion on reporting data of mitochondrial respiration in terms of metabolic flows and fluxes. Uniform standards for evaluation of respiratory states and rates will ultimately contribute to reproducibility between laboratories and thus support the development of data repositories of mitochondrial respiratory function in species, tissues, and cells. Clarity of concept and consistency of nomenclature facilitate effective transdisciplinary communication, education, and ultimately further discovery

Soroprevalência da infecção pelo vírus linfotrópico de células T humanas em parturientes de maternidade pública de Belém, Pará, Brasil

Introduction: The Human T Lymphotropic virus type-1 was first retrovirus identified and associated epidemiologically to leukemia/lymphoma T-cell adult (LLTA), tropical spastic parapesis (TSP), polymyositis, arthritis, uveitis, skin lesions and strongyloidiasis and other diseases. The vertical transmission has fundamental role on HTLV silent dispersion and the implementation of policies needs epidemiological indicators to develop prevention campaigns of infection transmission. Objective: To investigate the infection by the human T lymphotropic virus (HTLV-1 and HTLV-2) with parturients attended on public maternity of Belém, Pará, Brazil. Materials and Methods: A representative sample of parturients was investigated on period of March to August 2013, to detection of antibodies anti-HTLV by imunoenzimatic method (ELISA) and for research proviral genome by polymerase chain reaction. Results: The seroprevalence of 0.2% (1/452) identified one infected parturient who reported to be intravenous drug user and to have multiple sexual partners, without genotype identification. The postpartum carrier of HTLV did not breastfeed her newborn son, who showed no anti-HTLV antibodies one year after birth, like her mother and her older daughters, excluding the vertical familial transmission. Conclusion: This study identified a low but present prevalence of HTLV in pregnant women attended at a public maternity, as has been identified in other units of primary and secondary health care throughout Brazil, demonstrating the need for control measures of this infection in all levels of public health attention.CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorIntrodução: O vírus-T linfotrópico humano do tipo 1 (HTLV 1) foi o primeiro retrovírus humano a ser identificado e associado epidemiologicamente à Leucemia/Linfoma de células T do adulto (LLcTA), Paraparesia Espástica Tropical/Mielopatia Associada ao HTLV-1 (PET/MAH), polimiosite, artrite, uveíte, lesões dermatológicas e estrongiloidíase, entre outras doenças. A transmissão vertical tem papel fundamental na dispersão silenciosa HTLV e a implantação de políticas públicas necessita dos indicadores epidemiológicos para desenvolver ações de prevenção da transmissão da infecção. Objetivo: Investigar a infecção pelo Vírus Linfotrópico de Células T Humanas (HTLV-1 e HTLV-2) em parturientes atendidas em maternidade pública de Belém, Pará, Brasil. Material e Métodos: Uma amostra representativa de parturientes foi examinada, no período de março a agosto de 2013, para pesquisa de anticorpos anti-HTLV por método imunoenzimático (ELISA) e do genoma proviral, por meio da reação em cadeia da polimerase (PCR). Resultados: Foi identificada soroprevalência de 0,2% (1/452) em parturiente que relatou ser usuária de droga intravenosa e possuir múltiplos parceiros sexuais, sem identificação do genótipo. A parturiente optou por não amamentar seu filho recém-nascido, o qual não apresentou anticorpos anti-HTLV um ano após o nascimento, assim como sua mãe e suas filhas mais velhas, excluindo a transmissão familiar vertical. Conclusão: Este estudo identificou uma baixa, mas, presente prevalência de HTLV em parturientes atendidas em maternidade pública, assim como já identificado em outras unidades de atendimento primário e secundário de saúde de todo o Brasil, demonstrando a necessidade de medidas de controle desta infecção em todos os níveis de atenção à saúde pública

Occurrence of strongyloidiasis among patients with HTLV-1/2 seen at the outpatient clinic of the Núcleo de Medicina Tropical, Belém, State of Pará, Brazil

Introduction This study investigated the occurrence of Strongyloides stercoralis infestation and coinfection with HTLV-1/2 in Belém, Brazil. Methods S. stercoralis was investigated in stool samples obtained from individuals infected with HTLV-1/2 and their uninfected relatives. Results The frequency of S. stercoralis was 9% (9/100), including six patients infected with HTLV-1 (14.3%), two patients infected with HTLV-2 (11.1%), and one uninfected relative. Two cases of hyperinfestation by S. stercoralis were characterized as HTLV-1. Conclusions These results support the need for the routine investigation of S. stercoralis in patients with HTLV-1, in an attempt to prevent the development of severe forms of strongyloidiasis

Familial transmission of Human T-cell lymphotrophic virus: silent dissemination of an emerging but neglected infection

The authors want to thank PPSUS/FAPESPA/CNPq (PROJ_428_9577372) and CAPES and PROPESP/UFPA and PADESP. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.Universidade Federal do Pará. Núcleo de Medicina Tropical. Belém, PA, Brazil.Universidade Federal do Pará. Núcleo de Medicina Tropical. Belém, PA, Brazil.Universidade Federal do Pará. Núcleo de Medicina Tropical. Belém, PA, Brazil.Universidade Federal do Pará. Núcleo de Medicina Tropical. Belém, PA, Brazil.Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Universidade Federal do Pará. Instituto de Ciências Biológicas. Belém, PA, Brazil.Universidade Federal do Pará. Instituto de Ciências Biológicas. Belém, PA, Brazil.Universidade Federal do Pará. Instituto de Ciências Biológicas. Belém, PA, Brazil.Universidade Federal do Pará. Núcleo de Medicina Tropical. Belém, PA, Brazil.Universidade Federal do Pará. Núcleo de Medicina Tropical. Belém, PA, Brazil.Universidade Federal do Pará. Núcleo de Medicina Tropical. Belém, PA, Brazil / Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Universidade Federal do Pará. Núcleo de Medicina Tropical. Belém, PA, Brazil / Ministério da Saúde. Secretaria de Vigilância em Saúde. Instituto Evandro Chagas. Ananindeua, PA, Brasil.Background: HTLV-1 is a retrovirus that causes lymphoproliferative disorders and inflammatory and degenerative diseases of the central nervous system in humans. The prevalence of this infection is high in parts of Brazil and there is a general lack of public health care programs. As a consequence, official data on the transmission routes of this virus are scarce. Objective: To demonstrate familial aggregation of HTLV infections in the metropolitan region of Belém, Pará , Brazil. Method: A cross-sectional study involving 85 HTLV carriers treated at an outpatient clinic and other family members. The subjects were tested by ELISA and molecular methods between February 2007 and December 2010. Results: The prevalence of HTLV was 43.5 per cent (37/85) for families and 25.6 per cent (58/227) for the family members tested (95 per cent CI:1.33 to 3.79, P = 0.0033). Sexual and vertical transmission was likely in 38.3 per cent (23/60) and 20.4 per cent (29/142) of pairs, respectively (95 per cent CI: 1.25 to 4.69, P = 0.0130). Positivity was 51.3 per cent (20/39) and 14.3 per cent (3/21) in wives and husbands, respectively (95 per cent CI:0.04 to 0.63, P = 0.0057). By age group, seropositivity was 8.0 per cent (7/88) in subjects ,30 years of age and 36.7 per cent (51/139) in those of over 30 years (95 per cent CI: 0.06 to 0.34, P,0.0001). Positivity was 24.1 per cent (7/29) in the children of patients infected with HTLV-2, as against only 5.8 per cent (4/69) of those infected with HTLV-1 (95 per cent CI: 0.05 to 0.72, P = 0.0143). Conclusion: The results of this study indicate the existence of familial aggregations of HTLV characterized by a higher prevalence of infection among wives and subjects older than 30 years. Horizontal transmission between spouses was more frequent than vertical transmission. The higher rate of infection in children of HTLV-2 carriers suggests an increase in the prevalence of this virus type in the metropolitan region of Belém

Low genetic diversity of the Human T-cell Lymphotropic Virus (HTLV-1) in an endemic area of the Brazilian Amazon basin

<div><p>The Human T-cell Lymphotropic Virus (HTLV-1) is a <i>Deltaretrovírus</i> that was first isolated in the 1970s, and associated with Adult T-cell Leucemia-Lymphoma (ATLL), and subsequently to Tropical Spastic Paraparesis-Myelopathy (TSP/HAM). The genetic diversity of the virus varies among geographic regions, although its mutation rate is very low (approximately 1% per thousand years) in comparison with other viruses. The present study determined the genetic diversity of HTLV-1 in the metropolitan region of Belém, in northern Brazil. Blood samples were obtained from patients at the UFPA Tropical Medicine Nucleus between January 2010 and December 2013. The DNA was extracted and the PX region of the HTLV was amplified using nested PCR. The positive samples were then digested using the Taq1 enzyme for the identification and differentiation of the HTLV-1 and HTLV-2. The 5’LTR region of the positive HTLV-1 samples were amplified by nested PCR, and then sequenced genetically. The phylogenetic analysis of the samples was based on the maximum likelihood method and the evolutionary profile was analyzed by the Bayesian approach. Overall, 78 samples tested positive for HTLV-1, and 44 were analyzed here. The aA (cosmopolitan-transcontinental) subtype was recorded in all the samples. The following evolutionary rates were recorded for the different subtypes–a: 2.10−³, b: 2.69. 10−², c: 6.23. 10−², d: 3.08. 10−², e: 6. 10−², f: 1.78. 10−³, g: 2.2. 10−² mutations per site per year. The positive HTLV-1 samples tested in the present study were characterized by their low genetic diversity and high degree of stability.</p></div

Frequency of positive HTLV-1/HTLV-2 tests in relatives of HTLV carriers from Belém.

<p>Frequency of positive HTLV-1/HTLV-2 tests in relatives of HTLV carriers from Belém.</p

Schematic representation of the distribution of seropositive cases in the couples of families with HTLV-1/HTLV-2.

<p>Source: This image was made exclusively for the paper from data collected in Tropical Medicine Center, Belém, Pará, Brazil.</p

Frequency of positive HTLV-1/HTLV-2 tests in mother-offspring and spouse-spouse dyads of patients from Belém.

<p>Frequency of positive HTLV-1/HTLV-2 tests in mother-offspring and spouse-spouse dyads of patients from Belém.</p

Box-plot comparing the age of the seropositive and seronegative relatives of HTLV-1/HTLV-2 carriers from Belém.

<p>Source: This image was made exclusively for the paper from data collected in Tropical Medicine Center, Belém, Pará, Brazil.* Chi-square test.</p