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1.
PLoS Negl Trop Dis ; 15(6): e0009478, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34166369

RESUMO

BACKGROUND: Globally, schistosomiasis affects at least 240 million people each year with a high proportion of cases in sub-Saharan Africa. The infection presents a wide range of symptoms mainly at the gastrointestinal and urogenital level. Cases of schistosomiasis-related appendicitis are seldom reported. The aim of the present study is to identify the prevalence of schistosomiasis-related appendicitis in Beira, Mozambique and compare to global prevalence. METHODS: We retrospectively reviewed all cases of appendicitis recorded from January 2017 to March 2020 at a single pathology department located in Beira in order to assess the prevalence of schistosomiasis. Moreover, we performed a systematic review on the prevalence of schistosomiasis-related appendicitis in all countries. FINDINGS: A total of 145 appendicitis cases in Beira showed a 13.1% prevalence of schistosomal-related appendicitis. The mean age of patients was 29.1 years, and 14 (73.7%) were male. The systematic review identified 20 studies with 34,790 inpatients with schistosomiasis-related appendicitis with a global prevalence of 1.31% (95% confidence interval (CI): 0.72 to 2.06); a high heterogeneity (I2 = 96.0%) was observed. Studies carried out in Africa reported a significantly higher prevalence of schistosomiasis-related appendicitis (2.75%; 95% CI: 1.28 to 4.68) than those in Middle East (0.49%; 95% CI: 0.18 to 0.95) (p for interaction < 0.0001). CONCLUSIONS: Schistosomiasis infection should be considered as possible cause of appendicitis not only in endemic areas but also in developed countries. Considering that prevention is the best way to control the infection, more efforts should be put in place in order to increase the prevention coverage and avoid the cascading implications for health. This is even more so important in this Coronavirus Disease 2019 (COVID-19) era where the majority of attention and funds are used to fight the pandemic.


Assuntos
Apendicite/etiologia , Esquistossomose/complicações , Adulto , Apendicite/epidemiologia , Feminino , Humanos , Masculino , Prevalência , Estudos Retrospectivos
3.
Physiol Plant ; 161(2): 182-195, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28429526

RESUMO

Cyanobacteria play a pivotal role as the primary producer in many aquatic ecosystems. The knowledge on the interacting processes of cyanobacteria with its environment - abiotic and biotic factors - is still very limited. Many potential exocytoplasmic proteins in the model unicellular cyanobacterium Synechocystis PCC 6803 have unknown functions and their study is essential to improve our understanding of this photosynthetic organism and its potential for biotechnology use. Here we characterize a deletion mutant of Synechocystis PCC 6803, Δsll1783, a strain that showed a remarkably high light resistance which is related with its lower thylakoid membrane formation. Our results suggests Sll1783 to be involved in a mechanism of polysaccharide degradation and uptake and we hypothesize it might function as a sensor for cell density in cyanobacterial cultures.


Assuntos
Oxigenases de Função Mista/metabolismo , Polissacarídeos Bacterianos/metabolismo , Synechocystis/enzimologia , Tilacoides/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Espectrofotometria , Synechocystis/crescimento & desenvolvimento , Synechocystis/ultraestrutura
4.
J Photochem Photobiol B ; 152(Pt B): 383-94, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26051963

RESUMO

The serine type Deg/HtrA proteases are distributed in a wide range of organisms from Escherichia coli to humans. The cyanobacterium Synechocystis sp. PCC 6803 possesses three Deg protease orthologues: HtrA, HhoA and HhoB. Previously we compared Synechocystis 6803 wild type cells exposed to mild or severe stress conditions with a mutant lacking all three Deg proteases and demonstrated that stress had strong impact on the proteomes and metabolomes. To identify the biochemical processes, which this protease family is involved in, here we compared Synechocystis sp. PCC 6803 wild type cells with a mutant lacking all three Deg proteases grown under normal growth conditions (30°C and 40 µmol photons m(-2) s(-1)). Deletion of the Deg proteases lead to the down-regulation of proteins related to the biosynthesis of outer cell layers (e.g. the GDP mannose 4,6-dehydratase) and affected protein secretion. During the late growth phase of the culture Deg proteases were found to be secreted to the extracellular medium of the Synechocystis sp. PCC 6803 wild type strain. While cyanobacterial Deg proteases seem to act mainly in the periplasmic space, deletion of the three proteases influences the proteome and metabolome of the whole cell. Impairments in the outer cell layers of the triple mutant might explain the higher sensitivity toward light and oxidative stress, which was observed earlier by Barker and coworkers.


Assuntos
Serina Endopeptidases/metabolismo , Synechocystis/citologia , Synechocystis/enzimologia , Ativação Enzimática , Metabolômica , Mutação , Proteômica , Serina Endopeptidases/genética , Synechocystis/genética , Synechocystis/metabolismo
5.
J Voice ; 27(2): 187-94, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23294706

RESUMO

BACKGROUND: Previous studies with long-term average spectrum (LTAS) showed the importance of the glottal source for understanding the projected voices of actresses. In this study, electroglottographic (EGG) analysis was used to investigate the contribution of the glottal source to the projected voice, comparing actresses and nonactresses' voices, in different levels of intensity. METHOD: Thirty actresses and 30 nonactresses sustained vowels in habitual, moderate, and loud intensity levels. The EGG variables were contact quotient (CQ), closing quotient (QCQ), and opening quotient (QOQ). Other variables were sound pressure level (SPL) and fundamental frequency (F0). A KayPENTAX EGG was used. Variables were inputted in a general linear model. RESULTS/DISCUSSION: Actresses showed significantly higher values for SPL, in all levels, and both groups increased SPL significantly while changing from habitual to moderate and further to loud. There were no significant differences between groups for EGG quotients. There were significant differences between the levels only for F0 and CQ for both groups. CONCLUSION: SPL was significantly higher among actresses in all intensity levels, but in the EGG analysis, no differences were found. This apparently weak contribution of the glottal source in the supposedly projected voices of actresses, contrary to previous LTAS studies, might be because of a higher subglottal pressure or perhaps greater vocal tract contribution in SPL. Results from the present study suggest that trained subjects did not produce a significant higher SPL than untrained individuals by increasing the cost in terms of higher vocal fold collision and hence more impact stress. Future researches should explore the difference between trained and nontrained voices by aerodynamic measurements to evaluate the relationship between physiologic findings and the acoustic and EGG data. Moreover, further studies should consider both types of vocal tasks, sustained vowel and running speech, for both EGG and LTAS analysis.


Assuntos
Eletrodiagnóstico , Glote/fisiologia , Fonação , Acústica da Fala , Qualidade da Voz , Adulto , Fenômenos Biomecânicos , Feminino , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Pressão , Adulto Jovem
6.
J Proteomics ; 78: 294-311, 2013 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-23063787

RESUMO

Members of the DegP/HtrA protease family are widespread in nature and play an important role in proteolysis of misfolded and damaged proteins. The cyanobacterium Synechocystis sp. PCC 6803 contains three Deg proteases, HhoA (Sll1679), HhoB (Sll1427) and HtrA (Slr1204). Using the proteomic or metabolomic approach we investigated a triple deletion mutant (Δdeg) exposed to light or temperature stress. To cope with the stress conditions the triple mutant reduces its energy metabolism and stress-related proteins are induced to protect the cells. Additionally the co-expression of the genes encoding the three proteases with other genes in Synechocystis sp. PCC 6803 was analyzed. While HhoA seems to be involved in house-keeping processes related to protein (re)folding, protein clearance and signaling, the hhoB expression cluster is dominated by genes encoding periplasmic proteins linked to metabolism or signal transduction pathways. The htrA expression pattern is similar to that of genes encoding proteins of the electron transport chain, iron- and nitrogen metabolism. Our integrative approach indicates significant rearrangements in cells depleted of the Deg/HtrA proteases when exposed to stress, both, in the cytoplasmic and extracytoplasmic space.


Assuntos
Proteínas de Bactérias/biossíntese , Resposta ao Choque Térmico/efeitos da radiação , Luz , Metabolômica , Mutação , Proteômica , Serina Endopeptidases , Synechocystis/metabolismo , Proteínas de Bactérias/genética , Regulação Bacteriana da Expressão Gênica/genética , Regulação Bacteriana da Expressão Gênica/efeitos da radiação , Resposta ao Choque Térmico/genética , Synechocystis/genética
7.
PLoS One ; 7(9): e45713, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23029195

RESUMO

The widely distributed members of the Deg/HtrA protease family play an important role in the proteolysis of misfolded and damaged proteins. Here we show that the Deg protease rHhoA is able to degrade PsbO, the extrinsic protein of the Photosystem II (PSII) oxygen-evolving complex in Synechocystis sp. PCC 6803 and in spinach. PsbO is known to be stable in its oxidized form, but after reduction by thioredoxin it became a substrate for recombinant HhoA (rHhoA). rHhoA cleaved reduced eukaryotic (specifically, spinach) PsbO at defined sites and created distinct PsbO fragments that were not further degraded. As for the corresponding prokaryotic substrate (reduced PsbO of Synechocystis sp. PCC 6803), no PsbO fragments were observed. Assembly to PSII protected PsbO from degradation. For Synechocystis sp. PCC 6803, our results show that HhoA, HhoB, and HtrA are localized in the periplasma and/or at the thylakoid membrane. In agreement with the idea that PsbO could be a physiological substrate for Deg proteases, part of the cellular fraction of the three Deg proteases of Synechocystis sp. PCC 6803 (HhoA, HhoB, and HtrA) was detected in the PSII-enriched membrane fraction.


Assuntos
Proteínas de Bactérias/metabolismo , Synechocystis/metabolismo , Tiorredoxinas/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Sequência de Bases , Western Blotting , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Cinética , Espectrometria de Massas , Dados de Sequência Molecular , Proteólise , Proteínas Recombinantes/metabolismo , Frações Subcelulares/enzimologia , Especificidade por Substrato
8.
Biochem J ; 435(3): 733-42, 2011 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-21332448

RESUMO

Cyanobacteria require efficient protein-quality-control mechanisms to survive under dynamic, often stressful, environmental conditions. It was reported that three serine proteases, HtrA (high temperature requirement A), HhoA (HtrA homologue A) and HhoB (HtrA homologue B), are important for survival of Synechocystis sp. PCC 6803 under high light and temperature stresses and might have redundant physiological functions. In the present paper, we show that all three proteases can degrade unfolded model substrates, but differ with respect to cleavage sites, temperature and pH optima. For recombinant HhoA, and to a lesser extent for HtrA, we observed an interesting shift in the pH optimum from slightly acidic to alkaline in the presence of Mg2+ and Ca2+ ions. All three proteases formed different homo-oligomeric complexes with and without substrate, implying mechanistic differences in comparison with each other and with the well-studied Escherichia coli orthologues DegP (degradation of periplasmic proteins P) and DegS. Deletion of the PDZ domain decreased, but did not abolish, the proteolytic activity of all three proteases, and prevented substrate-induced formation of complexes higher than trimers by HtrA and HhoA. In summary, biochemical characterization of HtrA, HhoA and HhoB lays the foundation for a better understanding of their overlapping, but not completely redundant, stress-resistance functions in Synechocystis sp. PCC 6803.


Assuntos
Proteínas de Bactérias/metabolismo , Serina Endopeptidases/metabolismo , Synechocystis/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Cálcio/metabolismo , Deleção de Genes , Regulação Bacteriana da Expressão Gênica/fisiologia , Concentração de Íons de Hidrogênio , Magnésio/metabolismo , Dados de Sequência Molecular , Estrutura Terciária de Proteína , Serina Endopeptidases/genética , Especificidade por Substrato , Temperatura
9.
PLoS Med ; 7(3): e1000242, 2010 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-20231869

RESUMO

BACKGROUND: There is a growing recognition that the provision of surgical services in low-income countries is inadequate to the need. While constrained health budgets and health worker shortages have been blamed for the low rates of surgery, there has been little empirical data on the providers of surgery and cost of surgical services in Africa. This study described the range of providers of surgical care and anesthesia and estimated the resources dedicated to surgery at district hospitals in three African countries. METHODS AND FINDINGS: We conducted a retrospective cross-sectional survey of data from eight district hospitals in Mozambique, Tanzania, and Uganda. There were no specialist surgeons or anesthetists in any of the hospitals. Most of the health workers were nurses (77.5%), followed by mid-level providers (MLPs) not trained to provide surgical care (7.8%), and MLPs trained to perform surgical procedures (3.8%). There were one to six medical doctors per hospital (4.2% of clinical staff). Most major surgical procedures were performed by doctors (54.6%), however over one-third (35.9%) were done by MLPs. Anesthesia was mainly provided by nurses (39.4%). Most of the hospital expenditure was related to staffing. Of the total operating costs, only 7% to 14% was allocated to surgical care, the majority of which was for obstetric surgery. These costs represent a per capita expenditure on surgery ranging from US$0.05 to US$0.14 between the eight hospitals. CONCLUSION: African countries have adopted different policies to ensure the provision of surgical care in their respective district hospitals. Overall, the surgical output per capita was very low, reflecting low staffing ratios and limited expenditures for surgery. We found that most surgical and anesthesia services in the three countries in the study were provided by generalist doctors, MLPs, and nurses. Although more information is needed to estimate unmet need for surgery, increasing the funds allocated to surgery, and, in the absence of trained doctors and surgeons, formalizing the training of MLPs appears to be a pragmatic and cost-effective way to make basic surgical services available in underserved areas. Please see later in the article for the Editors' Summary.


Assuntos
Recursos em Saúde/economia , Recursos em Saúde/provisão & distribuição , Mão de Obra em Saúde/economia , Hospitais de Distrito/economia , Centro Cirúrgico Hospitalar/economia , África , Anestesia/estatística & dados numéricos , Estudos Transversais , Instalações de Saúde/provisão & distribuição , Pessoal de Saúde/estatística & dados numéricos , Humanos , Estudos Retrospectivos
10.
PLoS Med ; 7(3): e1000243, 2010 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-20231871

RESUMO

BACKGROUND: Surgical conditions contribute significantly to the disease burden in sub-Saharan Africa. Yet there is an apparent neglect of surgical care as a public health intervention to counter this burden. There is increasing enthusiasm to reverse this trend, by promoting essential surgical services at the district hospital, the first point of contact for critical conditions for rural populations. This study investigated the scope of surgery conducted at district hospitals in three sub-Saharan African countries. METHODS AND FINDINGS: In a retrospective descriptive study, field data were collected from eight district hospitals in Uganda, Tanzania, and Mozambique using a standardized form and interviews with key informants. Overall, the scope of surgical procedures performed was narrow and included mainly essential and life-saving emergency procedures. Surgical output varied across hospitals from five to 45 major procedures/10,000 people. Obstetric operations were most common and included cesarean sections and uterine evacuations. Hernia repair and wound care accounted for 65% of general surgical procedures. The number of beds in the studied hospitals ranged from 0.2 to 1.0 per 1,000 population. CONCLUSION: The findings of this study clearly indicate low levels of surgical care provision at the district level for the hospitals studied. The extent to which this translates into unmet need remains unknown although the very low proportions of live births in the catchment areas of these eight hospitals that are born by cesarean section suggest that there is a substantial unmet need for surgical services. The district hospital in the current health system in sub-Saharan Africa lends itself to feasible integration of essential surgery into the spectrum of comprehensive primary care services. It is therefore critical that the surgical capacity of the district hospital is significantly expanded; this will result in sustainable preventable morbidity and mortality. Please see later in the article for the Editors' Summary.


Assuntos
Hospitais de Distrito/estatística & dados numéricos , Centro Cirúrgico Hospitalar/estatística & dados numéricos , África Subsaariana , Distribuição por Idade , Cesárea/estatística & dados numéricos , Demografia , Feminino , Mão de Obra em Saúde/estatística & dados numéricos , Herniorrafia , Humanos , Masculino , Gravidez , Estudos Retrospectivos
12.
Photosynth Res ; 95(2-3): 135-45, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17912610

RESUMO

The cyanobacterial small CAB-like proteins (SCPs) are one-helix proteins with compelling similarity to the first and third transmembrane helix of proteins belonging to the CAB family of light-harvesting complex proteins in plants. The SCP proteins are transiently expressed at high light intensity and other stress conditions but their exact function remains largely unknown. Recently we showed association of ScpD with light-stressed, monomeric Photosystem II in Synechocystis sp. PCC 6803 (Yao et al. J Biol Chem 282:267-276, 2007). Here we show that ScpB associates with Photosystem II at normal growth conditions. Moreover, upon introduction of a construct into Synechocystis so that ScpB is expressed continuously under normal growth conditions, ScpE was detected under non-stressed conditions as well, and was copurified with tagged ScpB and Photosystem II. We also report on a one-helix protein, Slr1544, that is somewhat similar to the SCPs and whose gene is cotranscribed with that of ScpD; Slr1544 is another member of the extended light-harvesting-like (Lil) protein family, and we propose to name it LilA.


Assuntos
Proteínas de Bactérias/metabolismo , Complexo de Proteína do Fotossistema II/metabolismo , Synechocystis/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/química , Sequência de Bases , Northern Blotting , Western Blotting , Primers do DNA , Eletroforese em Gel de Poliacrilamida , Genes de Plantas , Dados de Sequência Molecular , Ligação Proteica , RNA de Plantas/genética , Homologia de Sequência de Aminoácidos , Synechocystis/genética , Espectrometria de Massas em Tandem
13.
Rev. bras. reumatol ; 47(2): 97-105, mar.-abr. 2007. tab
Artigo em Português | LILACS | ID: lil-455641

RESUMO

OBJETIVO: avaliar a possível associação entre fibromialgia e infecção crônica pelo vírus da hepatite C (VHC). MÉTODOS: estudo transversal com 186 pacientes fibromiálgicas e 55 pacientes com diagnóstico de doenças difusas do tecido conjuntivo (DDTC) não-fibromiálgicas, e em 33 pacientes com infecção crônica pelo VHC e 34 controles sem doenças infecciosas relacionadas ao fígado, todas do sexo feminino e de idade igual ou superior a 18 anos. A fibromialgia foi diagnosticada segundo os critérios classificatórios do American College of Rheumatology (ACR) de 1990. Infecção crônica pelo VHC foi definida pela presença do RNA do vírus por meio da reação em cadeia da polimerase (PCR). As demais variáveis consideradas para as manifestações extra-hepáticas associadas à infecção crônica compreenderam: fadiga, parestesias, fenômeno de Raynaud, sintomas de boca e/ou olhos secos, depressão e presença de títulos detectáveis de anticorpos antitireoidianos. RESULTADOS: a infecção crônica pelo VHC foi detectada em três pacientes (1,6 por cento) do grupo fibromiálgico e em nenhuma das pacientes com o diagnóstico de DDTC (p = 0,39). A dor musculoesquelética crônica disseminada foi mais prevalente no grupo de pacientes infectadas pelo VHC (45,5 por cento) do que no grupo-controle (26,5 por cento), mas não foi detectada associação entre fibromialgia e infecção crônica pelo VHC (OR = 1,39; IC 95 por cento = 0,43-4,57). Dentre as manifestações extra-hepáticas, apenas os sintomas relativos a boca e/ou olhos secos apresentaram uma associação com a infecção crônica (OR = 6,40; IC 95 por cento = 1,94-21,87). CONCLUSÃO: o estudo não detectou uma associação entre fibromialgia e infecção crônica pelo VHC.


OBJECTIVE: to evaluate a possible association between fibromyalgia and hepatitis C virus (HCV) chronic infection. METHODS: cross-sectional study comprising 186 fibromyalgic women, 55 non-fibromyalgic controls with a diagnosis of diffuse connective tissue diseases (DCTD), 33 HCV chronically infected women and 34 selected from the gastroenterology outpatient clinic with no liver related infection disease, all aged 18 or older. Fibromyalgia was diagnosed according to the American College of Rheumatology (ACR) classification criteria. Chronic HCV infection was defined by detection of HCV-RNA using the polymerase chain reaction (PCR). Other extra-hepatic manifestations comprised: fatigue, paresthesia, Raynaud´s phenomenon, sicca symptoms, depression and detectable thyroid autoantibodies. RESULTS: HCV-RNA was detected in 3 of the 185 fibromyalgic women (1.6 percent) and in none of the 55 DCTD group (p = 0.39). Chronic widespread musculoskeletal pain was more prevalent in the infected group (45.5 percent) than in the non-infected (26.5 percent), but no association was found between fibromyalgia and HCV chronic infection (OR = 1.39; 95 percent CI = 0.43-4.57). With the regard to other variables, only sicca symptoms were found to be associated with chronic infection (OR = 6.40; 95 percent CI = 1.94-21.87). CONCLUSION: we found no association between fibromyalgia and chronic HCV infection.

14.
Arq. méd. ABC ; 13(1/2): 40-42, 1990. tab
Artigo em Português | LILACS | ID: lil-93825

RESUMO

Os autores relatam um caso de shoshin beriberi em um paciente de 27 anos de idade, etilista, que desenvolveu um quadro de insuficiência cardíaca de alto débito, perda da resistência vascular periférica e grave acidose metabólica. O quadro cardiovascular e a acidose metabólica rapidamente melhoraram após administraçäo de tiamina. Patogênese e possíveis mecanismos säo discutidos


Assuntos
Humanos , Masculino , Adulto , Beriberi/complicações , Baixo Débito Cardíaco/etiologia , Tiamina/uso terapêutico , Acidose/metabolismo , Beriberi/tratamento farmacológico , Etanol/efeitos adversos
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