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1.
Hand Surg Rehabil ; 43(3): 101697, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38642741

RESUMO

OBJECTIVE: Trapeziometacarpal osteoarthritis is the second most common degenerative articular disease. Although initial therapy should be conservative, surgical treatment is often required. Several surgical techniques have been described, but none has proved to be a gold-standard. The objective of this study was to evaluate the long-term clinical and radiological results of trapeziometacarpal interposition arthroplasty with the PyroDisk implant (Integra LifeSciences). METHODS: A retrospective long-term study of all patients who underwent trapeziometacarpal interposition arthroplasty with a pyrocarbon implant at our institution was performed. RESULTS: Twenty-four patients who underwent PyroDisk (Integra LifeSciences). arthroplasty at our institution were identified; 7 were lost to follow-up; 17 patients were evaluated, for 20 arthroplasties. Mean follow-up was 13.5 years (range: 12-15 years). Disability in daily living activities was low (mean Disabilities of the Arm, Shoulder and Hand score, 29.6), with a mean pain score of 0.22. Mean Kapandji score at 13.5 years was 8.63. Mean grip strength was 18.5 kg and key-pinch strength 2.84 kg. Two patients had implant dislocation, needing revision surgery for implant removal. Implant survival rate was 88.9% at 13.5 years. CONCLUSIONS: Our study confirmed that good clinical results can be expected after interposition arthroplasty with PyroDisk (Integra LifeSciences). Regarding radiological findings, peri-implant osteolysis was present in 12 of the patients, but had no influence on the clinical outcome.


Assuntos
Carbono , Articulações Carpometacarpais , Força da Mão , Prótese Articular , Osteoartrite , Trapézio , Humanos , Osteoartrite/cirurgia , Estudos Retrospectivos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Articulações Carpometacarpais/cirurgia , Trapézio/cirurgia , Seguimentos , Artroplastia de Substituição , Avaliação da Deficiência , Medição da Dor , Materiais Biocompatíveis , Idoso de 80 Anos ou mais , Adulto , Atividades Cotidianas
2.
Toxicology ; 504: 153786, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522819

RESUMO

This study evaluated the effect of pharmacological inhibition of galectin 3 (Gal-3) with modified citrus pectin (MCP) on the heart and kidney in a model of cisplatin-induced acute toxicity. Male Wistar rats were divided into four groups (n = 6/group): SHAM, which received sterile saline intraperitoneally (i.p.) for three days; CIS, which received cisplatin i.p. (10 mg/kg/day) for three days; MCP, which received MCP orally (100 mg/kg/day) for seven days, followed by sterile saline i.p. for three days; MCP+CIS, which received MCP orally for seven days followed by cisplatin i.p. for three days. The blood, heart, and kidneys were collected six hours after the last treatment. MCP treatment did not change Gal-3 protein levels in the blood and heart, but it did reduce them in the kidneys of the MCP groups compared to the SHAM group. While no morphological changes were evident in the cardiac tissue, increased malondialdehyde (MDA) levels and deregulation of the mitochondrial oxidative phosphorylation system were observed in the heart homogenates of the MCP+CIS group. Cisplatin administration caused acute tubular degeneration in the kidneys; the MCP+CIS group also showed increased MDA levels. In conclusion, MCP therapy in the acute model of cisplatin-induced toxicity increases oxidative stress in cardiac and renal tissues. Further investigations are needed to determine the beneficial and harmful roles of Gal-3 in the cardiorenal system since it can act differently in acute and chronic diseases/conditions.


Assuntos
Antineoplásicos , Cisplatino , Galectina 3 , Rim , Pectinas , Ratos Wistar , Animais , Cisplatino/toxicidade , Pectinas/farmacologia , Masculino , Galectina 3/metabolismo , Galectina 3/antagonistas & inibidores , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Antineoplásicos/toxicidade , Ratos , Cardiotoxicidade , Miocárdio/metabolismo , Miocárdio/patologia , Malondialdeído/metabolismo , Coração/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Galectinas/metabolismo , Nefropatias/induzido quimicamente , Nefropatias/patologia , Nefropatias/prevenção & controle
3.
J Bras Pneumol ; 50(1): e20230233, 2024.
Artigo em Inglês, Português | MEDLINE | ID: mdl-38536982

RESUMO

Although lung cancer (LC) is one of the most common and lethal tumors, only 15% of patients are diagnosed at an early stage. Smoking is still responsible for more than 85% of cases. Lung cancer screening (LCS) with low-dose CT (LDCT) reduces LC-related mortality by 20%, and that reduction reaches 38% when LCS by LDCT is combined with smoking cessation. In the last decade, a number of countries have adopted population-based LCS as a public health recommendation. Albeit still incipient, discussion on this topic in Brazil is becoming increasingly broad and necessary. With the aim of increasing knowledge and stimulating debate on LCS, the Brazilian Society of Thoracic Surgery, the Brazilian Thoracic Association, and the Brazilian College of Radiology and Diagnostic Imaging convened a panel of experts to prepare recommendations for LCS in Brazil. The recommendations presented here were based on a narrative review of the literature, with an emphasis on large population-based studies, systematic reviews, and the recommendations of international guidelines, and were developed after extensive discussion by the panel of experts. The following topics were reviewed: reasons for screening; general considerations about smoking; epidemiology of LC; eligibility criteria; incidental findings; granulomatous lesions; probabilistic models; minimum requirements for LDCT; volumetric acquisition; risks of screening; minimum structure and role of the multidisciplinary team; practice according to the Lung CT Screening Reporting and Data System; costs versus benefits of screening; and future perspectives for LCS.


Assuntos
Neoplasias Pulmonares , Radiologia , Cirurgia Torácica , Humanos , Neoplasias Pulmonares/diagnóstico , Brasil/epidemiologia , Detecção Precoce de Câncer/métodos , Tomografia Computadorizada por Raios X/métodos , Programas de Rastreamento
4.
J. bras. pneumol ; 50(1): e20230233, 2024. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1550514

RESUMO

ABSTRACT Although lung cancer (LC) is one of the most common and lethal tumors, only 15% of patients are diagnosed at an early stage. Smoking is still responsible for more than 85% of cases. Lung cancer screening (LCS) with low-dose CT (LDCT) reduces LC-related mortality by 20%, and that reduction reaches 38% when LCS by LDCT is combined with smoking cessation. In the last decade, a number of countries have adopted population-based LCS as a public health recommendation. Albeit still incipient, discussion on this topic in Brazil is becoming increasingly broad and necessary. With the aim of increasing knowledge and stimulating debate on LCS, the Brazilian Society of Thoracic Surgery, the Brazilian Thoracic Association, and the Brazilian College of Radiology and Diagnostic Imaging convened a panel of experts to prepare recommendations for LCS in Brazil. The recommendations presented here were based on a narrative review of the literature, with an emphasis on large population-based studies, systematic reviews, and the recommendations of international guidelines, and were developed after extensive discussion by the panel of experts. The following topics were reviewed: reasons for screening; general considerations about smoking; epidemiology of LC; eligibility criteria; incidental findings; granulomatous lesions; probabilistic models; minimum requirements for LDCT; volumetric acquisition; risks of screening; minimum structure and role of the multidisciplinary team; practice according to the Lung CT Screening Reporting and Data System; costs versus benefits of screening; and future perspectives for LCS.


RESUMO O câncer de pulmão (CP) é uma das neoplasias mais comuns e letais no Brasil, e apenas 15% dos pacientes são diagnosticados nos estágios iniciais. O tabagismo persiste como o responsável por mais de 85% de todos os casos. O rastreamento do CP (RCP) por meio da TC de baixa dosagem de radiação (TCBD) reduz a mortalidade do CP em 20%, e, quando combinado com a cessação do tabagismo, essa redução chega a 38%. Na última década, diversos países adotaram o RCP como recomendação de saúde populacional. No Brasil, embora ainda incipiente, a discussão sobre o tema é cada vez mais ampla e necessária. Com o intuito de aumentar o conhecimento e estimular o debate sobre o RCP, a Sociedade Brasileira de Cirurgia Torácica, a Sociedade Brasileira de Pneumologia e Tisiologia e o Colégio Brasileiro de Radiologia e Diagnóstico por Imagem constituíram um painel de especialistas para elaborar as recomendações para o RCP. As recomendações aqui apresentadas foram baseadas em revisão narrativa da literatura, com ênfase em grandes estudos populacionais, em revisões sistemáticas e em recomendações de diretrizes internacionais, sendo construídas após ampla discussão pelo grupo de especialistas. Os temas revisados foram os seguintes: porque rastrear, considerações gerais sobre tabagismo, epidemiologia do CP, critérios de elegibilidade, achados incidentais, lesões granulomatosas, modelos probabilísticos, requisitos mínimos da TCBD, aquisições volumétricas, riscos do rastreamento, estrutura mínima e papel da equipe multidisciplinar, conduta segundo o Lung CT Screening Reporting and Data System (Lung-RADS), custos vs. benefícios e perspectivas do rastreamento.

5.
Microorganisms ; 11(8)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37630455

RESUMO

Antisepsis of the hands of medical personnel is one of the most important steps in the process of patient care, since direct contact can cause the cross-transfer of potentially pathogenic microorganisms at surgical sites. This study aimed to analyze the prevalence of microorganisms on the hands of 131 surgeons in a university hospital before the surgical procedure. Swabs were collected from each clinician's hands before and after handwashing. The samples were placed in a transport medium and immediately delivered to a private clinical analysis laboratory from São Luis-Maranhão. The microorganisms were identified by ionization source mass spectrometry and matrix-assisted laser desorption (MALDI-TOF), and antibiotic susceptibility tests (AST) were performed using the Vitek2 and Phoenix-BD automated system. The results showed a high frequency (100%) of microorganisms before handwashing, but after surgical antisepsis, the rate dropped significantly (p < 0.05) to 27.5%. The gram-positive species most detected were Staphylococcus spp. and Micrococcus luteus, representing 83.9%, followed by gram-negative species, Stenotrophomonas maltophilia, Acinetobacter baumanii, Pseudomonas aeruginosa, Pseudomonas gessardi, Pantoea septica, Serratia marcescens, and Burkholderia lata. The effectiveness of hand antisepsis was 72.5%, demonstrating that surgeons' hands are an important source of microorganisms that can cause infections in hospitalized patients in different care settings.

6.
Int J Mol Sci ; 25(1)2023 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-38203446

RESUMO

Lifestyle changes regarding diet composition and exercise training have been widely used as a non-pharmacological clinical strategy in the treatment of obesity, a complex and difficult-to-control disease. Taking the potential of exercise in the browning process and in increasing thermogenesis into account, the aim of this paper was to evaluate the effect of resistance, aerobic, and combination training on markers of browning of white adipose tissue from rats with obesity who were switched to a balanced diet with normal calorie intake. Different types of training groups promote a reduction in the adipose tissue and delta mass compared to the sedentary high-fat diet group (HS). Interestingly, irisin in adipose tissues was higher in the resistance exercise (RE) and aerobic exercise (AE) groups compared to control groups. Moreover, in adipose tissue, the fibroblast growth factor 21 (FGF21), coactivator 1 α (PGC1α), and peroxisome proliferator-activated receptor gamma (PPARγ) were higher in response to resistance training RE compared with the control groups, respectively. Additionally, uncoupling protein 1 (UCP1) showed higher levels in response to group AE compared to the HS group. In conclusion, the browning process in white adipose tissue responds differently toward different training exercise protocols, with resistance and aerobic training efficient in activating different biomarkers of the browning process, upregulating irisin, FGF21, PGC1α, PPARγ, and UCP1 in WAT, which together may suggest an improvement in the thermogenic process in the adipose tissue. Considering the experimental conditions of the present investigation, we suggest future research to pave new avenues to be applied in clinical practices to combat obesity.


Assuntos
Fibronectinas , PPAR gama , Animais , Ratos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo , Obesidade/terapia , Tecido Adiposo , Proteína Desacopladora 1
7.
Front Physiol ; 13: 920636, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35928558

RESUMO

Angiotensin-(1-7) is a peptide produced by different pathways, and regardless of the route, the angiotensin-converting enzyme 2 (ACE-2) is involved in one of the steps of its synthesis. Angiotensin-(1-7) binds to Mas receptors localized in different cells throughout the body. Whether angiotensin-(1-7) exerts any action in the urinary bladder (UB) is still unknown. We investigated the effects of intravenous and topical (in situ) administration of angiotensin-(1-7) on intravesical pressure (IP) and cardiovascular variables. In addition, the Mas receptors and ACE-2 gene and protein expression were analyzed in the UB. Adult female Wistar rats were anesthetized with 2% isoflurane in 100% O2 and submitted to the catheterization of the femoral artery and vein for mean arterial pressure (MAP) and heart rate (HR) recordings, and infusion of drugs, respectively. The renal blood flow was acquired using a Doppler flow probe placed around the left renal artery and the renal conductance (RC) was calculated as a ratio of Doppler shift (kHz) and MAP. The cannulation of the UB was performed for IP recording. We observed that angiotensin-(1-7) either administered intravenously [115.8 ± 28.6% angiotensin-(1-7) vs. -2.9 ± 1.3% saline] or topically [147.4 ± 18.9% angiotensin-(1-7) vs. 3.2 ± 2.8% saline] onto the UB evoked a significant (p < 0.05) increase in IP compared to saline and yielded no changes in MAP, HR, and RC. The marked response of angiotensin-(1-7) on the UB was also investigated using quantitative real-time polymerase chain reaction and western blotting assay, which demonstrated the mRNA and protein expression of Mas receptors in the bladder, respectively. ACE-2 mRNA and protein expression was also observed in the bladder. Therefore, the findings demonstrate that angiotensin-(1-7) acts in the UB to increase the IP and suggest that this peptide can be also locally synthesized in the UB.

8.
Front Cell Infect Microbiol ; 12: 807172, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35573777

RESUMO

Trypanosomatids are flagellate protozoans that can infect several invertebrate and vertebrate hosts, including insects and humans. The three most studied species are the human pathogens Trypanosoma brucei, Trypanosoma cruzi and Leishmania spp. which are the causative agents of Human African Trypanosomiasis (HAT), Chagas disease and different clinical forms of leishmaniasis, respectively. These parasites possess complex dixenous life cycles, with zoonotic and anthroponotic stages, and are transmitted by hematophagous insects. To colonize this myriad of hosts, they developed mechanisms, mediated by virulence factors, to infect, propagate and survive in different environments. In insects, surface proteins play roles in parasite attachment and survival in the insect gut, whilst in the mammalian host, the parasites have a whole group of proteins and mechanisms that aid them invading the host cells and evading its immune system components. Many studies have been done on the impact of these molecules in the vertebrate host, however it is also essential to notice the importance of these virulence factors in the insect vector during the parasite life cycle. When inside the insect, the parasites, like in humans, also need to survive defense mechanisms components that can inhibit parasite colonization or survival, e.g., midgut peritrophic membrane barrier, digestive enzymes, evasion of excretion alongside the digested blood meal, anatomic structures and physiological mechanisms of the anterior gut. This protection inside the insect is often implemented by the same group of virulence factors that perform roles of immune evasion in the mammalian host with just a few exceptions, in which a specific protein is expressed specifically for the insect vector form of the parasite. This review aims to discuss the roles of the virulence molecules in the insect vectors, showing the differences and similarities of modes of action of the same group of molecules in insect and humans, exclusive insect molecules and discuss possible genetic events that may have generated this protein diversity.


Assuntos
Doença de Chagas , Parasitos , Trypanosoma cruzi , Animais , Doença de Chagas/parasitologia , Humanos , Insetos Vetores/parasitologia , Insetos , Mamíferos , Proteínas de Membrana , Trypanosoma cruzi/fisiologia , Fatores de Virulência/genética
9.
Front Cell Infect Microbiol ; 11: 669079, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33937106

RESUMO

Trypanosoma brucei, Leishmania spp., and T. cruzi are flagellate protozoans of the family Trypanosomatidae and the causative agents of human African trypanosomiasis, leishmaniasis, and Chagas disease, respectively. These diseases affect humans worldwide and exert a significant impact on public health. Over the course of evolution, the parasites associated with these pathologies have developed mechanisms to circumvent the immune response system throughout the infection cycle. In cases of human infection, this function is undertaken by a group of proteins and processes that allow the parasites to propagate and survive during host invasion. In T. brucei, antigenic variation is promoted by variant surface glycoproteins and other proteins involved in evasion from the humoral immune response, which helps the parasite sustain itself in the extracellular milieu during infection. Conversely, Leishmania spp. and T. cruzi possess a more complex infection cycle, with specific intracellular stages. In addition to mechanisms for evading humoral immunity, the pathogens have also developed mechanisms for facilitating their adhesion and incorporation into host cells. In this review, the different immune evasion strategies at cellular and molecular levels developed by these human-pathogenic trypanosomatids have been discussed, with a focus on the key molecules responsible for mediating the invasion and evasion mechanisms and the effects of these molecules on virulence.


Assuntos
Doença de Chagas , Leishmaniose , Trypanosoma brucei brucei , Trypanosoma cruzi , Humanos , Virulência
10.
Rev. Pesqui. Fisioter ; 11(1): 59-67, Fev. 2021. ilus, tab
Artigo em Inglês, Português | LILACS | ID: biblio-1252888

RESUMO

INTRODUÇÃO: O suspiro caracteriza-se pela realização de uma inspiração lenta e profunda, seguida de uma expiração lenta. Estudos sugerem que a adição de um suspiro por minuto em pacientes com síndrome do desconforto respiratório agudo, ventilados em PSV, melhora a oxigenação e a mecânica pulmonar. OBJETIVO: Avaliar o impacto da manobra de recrutamento alveolar através de suspiro na mecânica pulmonar e oxigenação em pacientes ventilados mecanicamente, além de verificar o impacto hemodinâmico e a incidência de intercorrências associadas à utilização da técnica. MATERIAIS E MÉTODOS: Estudo experimental com 17 pacientes em ventilação mecânica, apresentando relação entre pressão parcial de oxigênio alveolar e fração inspirada de oxigênio (PaO2/FiO2) inferior a 300mmHg. Avaliou-se dados respiratórios, de mecânica pulmonar e hemodinâmicos. Os dados foram coletados durante três períodos: antes do suspiro, imediatamente após e 15 minutos depois da técnica. Dois suspiros por minuto foram administrados utilizando pressão em vias aéreas limitada em 40cmH2O, durante um tempo inspiratório de quatro segundos. RESULTADOS: Após o suspiro, observou-se aumento da PaO2, pressão resistiva, complacência estática e relação PaO2/FiO2, além de diminuição da pressão de platô e pressão parcial de gás carbônico alveolar (PaCO2). Após 15 minutos da retirada do suspiro observou-se que a PaO2, pressão resistiva, complacência estática e relação PaO2/ FiO2 mantiveram-se acima do valor basal, enquanto que a pressão de platô manteve-se abaixo. Não foi observada alteração significante nas variáveis hemodinâmicas. CONCLUSÃO: O suspiro em pacientes ventilados mecanicamente foi capaz de melhorar a oxigenação e a mecânica pulmonar sem comprometer a estabilidade hemodinâmica.


INTRODUCTION: The sigh is characterized by a slow and deep inhalation, followed by a slow exhalation. Studies suggest that the addition of one breath per minute in patients with acute respiratory distress syndrome, ventilated on PSV, improves oxygenation and pulmonary mechanics. OBJECTIVE: Analyze the impact of the alveolar recruitment maneuver through breath in pulmonary mechanics and oxygenation in mechanically ventilated patients, in addition to checking the hemodynamic impact and the incidence of complications associated with the use of the technique. MATERIALS AND METHODS: Experimental study with 17 patients on mechanical ventilation, showing a relationship between partial pressure of alveolar oxygen and fraction of inspired oxygen (PaO2/FiO2) below 300mmHg. Respiratory, pulmonary mechanics, and hemodynamic data were evaluated. Data were collected during three periods: before sigh, immediately after, and 15 minutes after the technique. Two sighs per minute were administered using airways pressure limited to 40 cmH2O, during an inspiratory time of four seconds. RESULTS: After the sigh, there was an increase in PaO2, resistive pressure, static compliance, and PaO2/FiO2 ratio, in addition to a decrease in plateau pressure and partial pressure of alveolar carbon dioxide (PaCO2). After 15 minutes of sigh removal, it was observed that PaO2, resistive pressure, static compliance, and PaO2/ FiO2 ratio remained above the baseline, while the plateau pressure remained below. There was no significant change in hemodynamic variables. CONCLUSION: The sigh in mechanically ventilated patients was able to improve oxygenation and pulmonary mechanics without compromising hemodynamic stability


Assuntos
Oxigenação , Respiração Artificial , Síndrome do Desconforto Respiratório do Recém-Nascido
11.
Knee Surg Sports Traumatol Arthrosc ; 29(1): 8-43, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30413860

RESUMO

PURPOSE: The goal of this systematic review and meta-analysis was to identify the main risk factors for periprosthetic joint infection (PJI) in patients undergoing total hip or knee arthroplasties. METHODS: A systematic review was conducted of the potential risk factors for PJI in total hip or total knee arthroplasty. Risk factors were compared and grouped according to demographics, comorbidities, behavior, infections, native joint diseases and other patient-related and procedure-related factors. Meta-analysis (random-effects models) was conducted using odds ratio (OR) and mean difference (MD). Risk of bias (ROBBINS-I) and strength of the evidence (GRADE) were assessed. RESULTS: The study included 37 studies (2,470,827 patients). Older age was a protective factor (MD = - 1.18). Male gender (OR 1.34), coagulopathy (3.05), congestive heart failure (2.36), diabetes mellitus (1.80), obesity (1.61), systemic neoplasia (1.57), chronic lung disease (1.52), and hypertension (1.21) increased the risk for PJI. Behavioral risk factors comprised alcohol abuse (2.95), immunosuppressive therapy (2.81), steroid therapies (1.88), and tobacco (1.82). Infectious risk factors included surgical site infections (6.14), postoperative urinary tract infections (2.85), and prior joint infections (2.15). Rheumatoid arthritis, posttraumatic native joint disease, high National Nosocomial Infections Surveillance (NNIS) system surgical patient index score, prior joint operation, American Society of Anesthesiologists score ≥ 3 and obesity were also significantly associated with higher risk of PJI. Osteoarthritis and blood transfusion were protective factors. CONCLUSIONS: The main risk factors for PJI in each category were male gender, coagulopathy, alcohol abuse, surgical site infection (highest score) and high NNIS system surgical patient index score. Protective factors were age, female gender in TKA, osteoarthritis and blood transfusion. Optimization of modifiable risk factors for PJI should be attempted in clinical practice. LEVEL OF EVIDENCE: II.


Assuntos
Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Artropatias/epidemiologia , Infecções Relacionadas à Prótese/epidemiologia , Fatores Etários , Idoso , Transfusão de Sangue/métodos , Feminino , Humanos , Artropatias/etiologia , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Razão de Chances , Osteoartrite/epidemiologia , Osteoartrite/cirurgia , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/cirurgia , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia
12.
Trends Parasitol ; 37(4): 317-329, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33308952

RESUMO

The trypanosomatids Trypanosoma brucei, Trypanosoma cruzi, and Leishmania spp. are flagellate eukaryotic parasites that cause serious diseases in humans and animals. These parasites have cell shapes defined by a subpellicular microtubule array and all share a number of important cellular features. One of these is the flagellar pocket, an invagination of the cell membrane around the proximal end of the flagellum, which is an important organelle for endo/exocytosis. The flagellar pocket plays a crucial role in parasite pathogenicity and persistence in the host and has a great influence on cell morphogenesis and cell division. Here, we compare the morphology and function of the flagellar pockets between different trypanosomatids, with their life cycles and ecological niches likely influencing these differences.


Assuntos
Trypanosomatina , Flagelos/ultraestrutura , Interações Hospedeiro-Parasita , Relação Estrutura-Atividade , Trypanosomatina/patogenicidade , Trypanosomatina/fisiologia , Trypanosomatina/ultraestrutura
13.
J Cell Biol ; 220(1)2021 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-33165561

RESUMO

Cilia and flagella are required for cell motility and sensing the external environment and can vary in both length and stability. Stable flagella maintain their length without shortening and lengthening and are proposed to "lock" at the end of growth, but molecular mechanisms for this lock are unknown. We show that CEP164C contributes to the locking mechanism at the base of the flagellum in Trypanosoma brucei. CEP164C localizes to mature basal bodies of fully assembled old flagella, but not to growing new flagella, and basal bodies only acquire CEP164C in the third cell cycle after initial assembly. Depletion of CEP164C leads to dysregulation of flagellum growth, with continued growth of the old flagellum, consistent with defects in a flagellum locking mechanism. Inhibiting cytokinesis results in CEP164C acquisition on the new flagellum once it reaches the old flagellum length. These results provide the first insight into the molecular mechanisms regulating flagella growth in cells that must maintain existing flagella while growing new flagella.


Assuntos
Flagelos/metabolismo , Proteínas de Protozoários/metabolismo , Trypanosoma brucei brucei/metabolismo , Corpos Basais/metabolismo , Ciclo Celular , Linhagem Celular , Flagelos/ultraestrutura , Técnicas de Silenciamento de Genes , Interferência de RNA , Trypanosoma brucei brucei/citologia , Trypanosoma brucei brucei/ultraestrutura
14.
PLoS Negl Trop Dis ; 14(7): e0008488, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32716931

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) is a major neglected disease, potentially fatal, whose control is still impaired by inefficient and/or expensive treatment and diagnostic methods. The most promising approach for VL diagnosis uses serological assays with recombinant proteins, since they are more efficient and easier to perform. Tests developed for the human form of the disease, however, have not been shown to be efficient for its diagnosis in the canine host, the major reservoir for the American VL. METHODOLOGY/PRINCIPAL FINDINGS: Here, we describe a systematic approach aimed at the production of a new chimeric protein potentially able to be used for both human and canine VL diagnosis and based both on in silico gene design and experimental data. Starting from the previous identification of Leishmania infantum recombinant antigens efficient for the diagnosis of either human or canine VL, three of the best performing antigens were selected (Lci2, Lci3 and Lci12). After a preliminary evaluation validating the chimeric approach, DNA fragments encoding predicted antigenic regions from each protein, enriched with repeats, were joined in various combinations to generate a total of seventeen chimeric genes optimized for prokaryotic expression. These were assessed for optimal expression and purification yield, with four chimeric proteins being efficiently produced. Their diagnostic potential was then evaluated through ELISA assays with sera from VL afflicted humans and dogs. After two rounds of gene design, the results showed high levels of sensitivity for the best chimeric protein, named Q5, in humans (82%) and dogs (100%) with 100% specificity in comparison with healthy controls. A single non-specific reaction was seen with serum from individuals with tegumentary leishmaniasis. CONCLUSION: The newly described chimeric protein is potentially useful for the detection of both humans and dogs afflicted with VL, with its use in rapid tests necessary for validation as a new diagnostic tool.


Assuntos
Doenças do Cão/diagnóstico , Leishmaniose Visceral/veterinária , Testes Sorológicos/veterinária , Sequência de Aminoácidos , Animais , Antígenos de Protozoários/química , Doenças do Cão/sangue , Cães , Escherichia coli/metabolismo , Regulação da Expressão Gênica , Humanos , Leishmaniose Visceral/sangue , Leishmaniose Visceral/diagnóstico , Proteínas de Protozoários/química , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Sensibilidade e Especificidade , Testes Sorológicos/métodos , Transcriptoma
15.
BMC Genomics ; 20(1): 118, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30732584

RESUMO

BACKGROUND: The leishmaniasis are parasitic diseases caused by protozoans of the genus Leishmania, highly divergent eukaryotes, characterized by unique biological features. To survive in both the mammalian hosts and insect vectors, these pathogens make use of a number of mechanisms, many of which are associated with parasite specific proteases. The metalloprotease GP63, the major Leishmania surface antigen, has been found to have multiple functions required for the parasite's survival. GP63 is encoded by multiple genes and their copy numbers vary considerably between different species and are increased in those from the subgenus Viannia, including L. braziliensis. RESULTS: By comparing multiple sequences from Leishmania and related organisms this study sought to characterize paralogs in silico, evaluating their differences and similarities and the implications for the GP63 function. The Leishmania GP63 genes are encoded on chromosomes 10, 28 and 31, with the genes from the latter two chromosomes more related to genes found in insect or plant parasites. Those from chromosome 10 have experienced independent expansions in numbers in Leishmania, especially in L. braziliensis. These could be clustered in three groups associated with different mRNA 3' untranslated regions as well as distinct C-terminal ends for the encoded proteins, with presumably distinct expression patterns and subcellular localizations. Sequence variations between the chromosome 10 genes were linked to intragenic recombination events, mapped to the external surface of the proteins and predicted to be immunogenic, implying a role against the host immune response. CONCLUSIONS: Our results suggest a greater role for the sequence variation found among the chromosome 10 GP63 genes, possibly related to the pathogenesis of L. braziliensis and closely related species within the mammalian host. They also indicate different functions associated to genes mapped to different chromosomes. For the chromosome 10 genes, variable subcellular localizations were found to be most likely associated with multiple functions and target substrates for this versatile protease.


Assuntos
Simulação por Computador , Variação Genética , Evasão da Resposta Imune/genética , Leishmania braziliensis/genética , Leishmania braziliensis/imunologia , Metaloendopeptidases/genética , Sequência de Aminoácidos , Cromossomos/genética , Epitopos de Linfócito B/imunologia , Evolução Molecular , Leishmania braziliensis/patogenicidade , Metaloendopeptidases/química , Recombinação Genética , Homologia de Sequência do Ácido Nucleico , Virulência/genética
16.
Rev. odontol. Univ. Cid. São Paulo (Online) ; 30(1): 54-63, jan.-mar. 2018. ilus.
Artigo em Português | LILACS, BBO - Odontologia | ID: biblio-965206

RESUMO

A órbita é uma escavação óssea no crânio, que tem função de apoio e proteção ao bulbo do olho, seus vasos e nervos. Ela é uma pirâmide óssea composta por 7 ossos que compõem quatro paredes: um teto, uma base, parede lateral e medial; são eles o osso esfenoidal, etmoide, maxila, palatino, placa orbital do osso frontal, zigomático e lacrimal. O nervo óptico é composto pelas células ganglionares da retina e comunica o globo ocular ao cérebro. Pode ser dividido em 4 partes que possuem comprimentos diferentes, num total de 50mm, divididos em partes intraocular, intraorbital, intracanalicular e intracraniano. Tanto a órbita quanto o nervo óptico devem estar dentro dos parâmetros anatômicos de normalidade e qualquer alteração nesse padrão é uma possível causa de perda ou diminuição da acuidade visual. Uma dessas possíveis causas da diminuição da acuidade poderia ser uma anormalidade anatômica dos ossos orbitais, causando uma diminuição ou distorção do espaço orbital. Outra hipótese pode ser uma desproporção entre as dimensões do nervo óptico e o forame óptico, causando uma compressão e consequente lesão nervosa, ou até mesmo a existência de uma desproporção entre a cavidade orbital e os diâmetros do nervo óptico. Para compreender a relação entre a perda da acuidade visual e as alterações anatômicas citadas é essencial estabelecer o padrão de normalidade da órbita e do nervo óptico e suas dimensões. Para o tipo de análise proposta, a tomografia computadorizada helicoidal pode fornecer esses padrões de normalidade. Com esse intuito, foram observados 50 exames em cortes axiais representando a cavidade orbital, o canal óptico e o nervo óptico que foram identificados e mensurados pelo programa OsiriX. O comprimento da cavidade da órbita apontou para o lado direito, média de 39,40mm e, lado esquerdo, média de 38,40mm. O comprimento da parte intraorbital do nervo óptico para o olho direito, média 23,90mm e o olho esquerdo, média de 23,60mm. O diâmetro do canal óptico do lado direito alcançou um valor médio de 4,900mm e do lado esquerdo obteve uma média de 4,290mm. Por meio da análise do presente estudo foi possível estabelecer valores numéricos para o padrão de normalidade, permitindo investigações causais posteriores.


The orbit is a bone digging in the skull, which has a supporting and protective function to the eye bulb, its vessels and nerves. It is a bone pyramid composed of 7 bones that consists of four walls: a ceiling, a base, lateral and medial wall. They are the sphenoid bone, ethmoid, maxilla, palatine, orbital plaque of the frontal bone, zygomatic and lacrimal. The optic nerve is composed of the ganglion cells of the retina, and they communicate the ocular globe to the cortex. It can be divided into 4 parts that present different lengths, being a total of 50mm, divided into intraocular, intraorbital, intracanalicular and intracranial parts. Both the orbit and the optic nerve must be within the anatomical parameters of normality, and any change in this pattern is a possible cause of loss or decrease of visual acuity. One of these possible causes of decreased acuity could be an anatomical abnormality of the orbital bones, causing a decrease or distortion of the orbital space. Another hypothesis may be a disproportion between the dimensions of the optic nerve and the optic foramen, causing a compression and consequent nerve damage, or even the existence of a disproportion between the orbital cavity and the diameters of the optic nerve. To understand the relationship between loss of visual acuity and the anatomical changes cited, it is essential to establish the normality of the orbit and optic nerve and its dimensions. For analysis proposed, helical computerized tomography can provide these normality patterns. For this purpose, 50 exams were performed on axial sections representing the orbital cavity, optic canal and optic nerve that were identified and measured by the OsiriX program. The cavity length of the orbit was to the right side, mean of 39.40mm and left side: mean of 38.40mm. The length of the intraorbital portion of the optic nerve to the right eye, mean 23.90mm and the left eye, mean of 23.60mm. The diameter of the optical channel on the right side reached an average value of 4.900mm and the left side obtained an average of 4.290mm. Through the analysis of the present study it was possible to establish numerical values for the normality pattern allowing further causal investigations.


Assuntos
Nervo Óptico , Tomografia Computadorizada Espiral , Órbita
17.
PLoS One ; 12(9): e0184867, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28957332

RESUMO

Current strategies for the control of zoonotic visceral leishmaniasis (VL) rely on its efficient diagnosis in both human and canine hosts. The most promising and cost effective approach is based on serologic assays with recombinant proteins. However, no single antigen has been found so far which can be effectively used to detect the disease in both dogs and humans. In previous works, we identified Leishmania infantum antigens with potential for the serodiagnosis of VL. Here, we aimed to expand the panel of the available antigens for VL diagnosis through another screening of a genomic expression library. Seven different protein-coding gene fragments were identified, five of which encoding proteins which have not been previously studied in Leishmania and rich in repetitive motifs. Poly-histidine tagged polypeptides were generated from six genes and evaluated for their potential for diagnosis of VL by ELISA (Enzyme Linked ImmunoSorbent Assay) with sera from infected humans and dogs. None of those was valid for the detection of human VL (26-52% sensitivity) although their performance was increased in the canine sera (48-91% sensitivity), with one polypeptide useful for the diagnosis of canine leishmaniasis. Next, we assayed a mixture of three antigens, found to be best for human or canine VL, among 13 identified through different screenings. This "Mix" resulted in similar levels of sensitivity for both human (84%) and canine (88%) sera. With improvements, this validates the use of multiple proteins, including antigens identified here, as components of a single system for the diagnosis of both forms of leishmaniasis.


Assuntos
Antígenos de Protozoários/imunologia , Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/veterinária , Proteínas Recombinantes/imunologia , Testes Sorológicos/métodos , Sequência de Aminoácidos , Animais , Antígenos de Protozoários/química , Cães , Eletroforese em Gel de Poliacrilamida , Ensaio de Imunoadsorção Enzimática , Humanos , Leishmania infantum/imunologia , Leishmaniose Visceral/sangue , Peptídeos/metabolismo , Análise de Sequência de Proteína
18.
RGO (Porto Alegre) ; 64(4): 460-466, Oct.-Dec. 2016. graf
Artigo em Inglês | LILACS | ID: biblio-842351

RESUMO

ABSTRACT Paraendodontic surgeries have been increasingly used to solve problems related to failures in conventional endodontic treatment. Better anatomical knowledge of the structures as well as the development of techniques and materials involved has resulted in substantial paraendodontic surgery increase and success. In some cases, teeth endodontic treatment highly benefits treatment accomplishment. This report describes a case of an endodontic treatment complemented by paraendodontic surgery in periapical region of 21, 22 and 23 of a female patient who had been treated at the clinic of the Brazilian Dental Association Dentistry - in the city of Cascavel, State of Parana, Brazil. The case presents a 12-month follow-up for the resolution of painful symptoms, lesion reduction, and bone formation. Literature review was performed regarding paraendodontic surgery in order to assess the determining factors, failure causes and procedure indications/contraindications, as well.


RESUMO A cirurgia paraendodôntica tem sido cada vez mais utilizada para sanar problemas inerentes aos insucessos no tratamento endodôntico convencional. O melhor conhecimento anatômico das estruturas envolvidas bem como a evolução das técnicas e dos materiais proporcionou um aumento significativo da utilização desta técnica e, por conseguinte seu maior sucesso. O tratamento endodôntico primário de um elemento dentário pode atingir altos índices de sucesso. Tornando-se, portanto, imprescindível para se atingir o sucesso do tratamento de alguns casos. Neste trabalho descreve-se um caso de tratamento endodôntico complementado por cirurgia paraendodôntica em região periapical dos elementos dentais 21, 22 e 23 de paciente do gênero feminino que foi tratada na Clínica de Odontologia da Associação Brasileira de Odontologia - Regional de Cascavel, Pr. O caso apresenta acompanhamento de 12 meses com resolução da sintomatologia dolorosa, redução da lesão e neoformação óssea. Foi realizada uma discussão com revisão da literatura sobre a cirurgia paraendodôntica avaliando os fatores determinantes, causas de insucessos, indicações e contraindicações do procedimento.

19.
Acta sci., Biol. sci ; 38(2): 157-161, abr.-jun. 2016.
Artigo em Inglês | LILACS | ID: biblio-2536

RESUMO

The effects of different light quality treatments on in vitro growth and multiplication of sugarcane (RB867515) were investigated. The plantlets were cultivated on MS medium containing 1.3 µM 6-benzylaminopurine (BAP), and exposed to five light treatments: three combinations of blue/red LED (70:30, 50:50, 30:70), white-LED and fluorescent lamps, during 24 days. Among the LED light treatments, blue/red combination in 50:50 proportions proved to have the best results for stem length, fresh mass, leaf number and shoot multiplication. Higher content of photosynthetic pigments was also obtained with LEDs. Results suggested that the light quality emitted by LEDs was suitable for plant growth and development and it may be used as alternative and economic light source for micropropagation of sugarcane variety under analysis.


Foram investigados os efeitos de diferentes tratamentos de qualidade da luz sobre o crescimento e multiplicação in vitro de cana-de-açúcar (RB867515). As plantas foram cultivadas em meio MS contendo 1,3 µ M de 6-benzilaminopurina (BAP) e expostas a cinco tratamentos de luz: três combinações de LED azul/vermelho (70:30, 50:50, 30:70), LED branco e lâmpadas fluorescentes, durante 24 dias. Entre os tratamentos de luz de LED, a combinação azul/vermelho na proporção 50:50 apresentou os melhores resultados para altura, massa fresca, número de folhas e multiplicação de brotos. Maior teor de pigmentos fotossintéticos também foi obtido com a utilização de LEDs. Os resultados sugerem que a qualidade da luz emitida pelos LEDs foi adequada para o crescimento e desenvolvimento das plantas e pode ser utilizada como fonte de luz alternativa e econômica para a micropropagação da variedade de cana-de-açúcar estudada.


Assuntos
Saccharum/crescimento & desenvolvimento , Técnicas In Vitro/métodos , Luz
20.
Nano Lett ; 16(3): 1695-703, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26845418

RESUMO

The recent development of core/shell engineering of rare earth doped luminescent nanoparticles has ushered a new era in fluorescence thermal biosensing, allowing for the performance of minimally invasive experiments, not only in living cells but also in more challenging small animal models. Here, the potential use of active-core/active-shell Nd(3+)- and Yb(3+)-doped nanoparticles as subcutaneous thermal probes has been evaluated. These temperature nanoprobes operate in the infrared transparency window of biological tissues, enabling deep temperature sensing into animal bodies thanks to the temperature dependence of their emission spectra that leads to a ratiometric temperature readout. The ability of active-core/active-shell Nd(3+)- and Yb(3+)-doped nanoparticles for unveiling fundamental tissue properties in in vivo conditions was demonstrated by subcutaneous thermal relaxation monitoring through the injected core/shell nanoparticles. The reported results evidence the potential of infrared luminescence nanothermometry as a diagnosis tool at the small animal level.


Assuntos
Medições Luminescentes/instrumentação , Nanopartículas/química , Neodímio/química , Termômetros , Itérbio/química , Administração Cutânea , Animais , Temperatura Corporal , Raios Infravermelhos , Luminescência , Camundongos , Nanopartículas/administração & dosagem , Neodímio/administração & dosagem , Fenômenos Fisiológicos da Pele , Itérbio/administração & dosagem
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