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1.
Xenotransplantation ; 30(5): e12820, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37735958

RESUMO

Xenotransplantation is a promising approach to reduce organ shortage, while genetic modification of donor pigs has significantly decreased the immunogenic burden of xenotransplants, organ rejection is still a hurdle. Genetically modified pig organs are used in xenotransplantation research, and the first clinical pig-to-human heart transplantation was performed in 2022. However, the impact of genetic modification has not been investigated on a cellular level yet. Endothelial cells (EC) and their sugar-rich surface known as the glycocalyx are the first barrier encountering the recipient's immune system, making them a target for rejection. We have previously shown that wild type venous but not arterial EC were protected against heparan sulfate (HS) shedding after activation with human serum or human tumor necrosis factor alpha (TNF𝛼). Using a 2D microfluidic system we investigated the glycocalyx dynamics of genetically modified porcine arterial and venous EC (Gal𝛼1,3 Gal knock-out, transgenic for human CD46 and thrombomodulin, GTKO/hCD46/hTM) after activation with human serum or human TNF𝛼. Interestingly, we observed that GTKO/hCD46/hTM arterial cells, additionally to venous cells, do not shed HS. Unscathed HS on GTKO/hCD46/hTM EC correlated with reduced complement deposition, suggesting that protection against complement activation contributes to maintaining an intact glycocalyx layer on arterial EC. This protection was lost on GTKO/hCD46/hTM cells after simultaneous perfusion with human serum and human TNF𝛼. HS shedding on arterial cells and increased complement deposition on both arterial and venous cells was observed. These findings suggest that GTKO/hCD46/hTM EC revert to a proinflammatory phenotype in an inflammatory xenotransplantation setting, potentially favoring transplant rejection.


Assuntos
Células Endoteliais , Glicocálix , Animais , Humanos , Suínos , Transplante Heterólogo , Animais Geneticamente Modificados , Proteínas do Sistema Complemento
2.
BMC Infect Dis ; 23(1): 447, 2023 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-37400753

RESUMO

BACKGROUND: To improve tuberculosis (TB) diagnosis, the World Health Organisation (WHO) has called for a non-sputum based triage test to focus TB testing on people with a high likelihood of having active pulmonary tuberculosis (TB). Various host or pathogen biomarker-based testing devices are in design stage and require validity assessment. Host biomarkers have shown promise to accurately rule out active TB, but further research is required to determine generalisability. The TriageTB diagnostic test study aims to assess the accuracy of diagnostic test candidates, as well as field-test, finalise the design and biomarker signature, and validate a point-of-care multi-biomarker test (MBT). METHODS: This observational diagnostic study will evaluate sensitivity and specificity of biomarker-based diagnostic candidates including the MBT and Xpert® TB Fingerstick cartridge compared with a gold-standard composite TB outcome classification defined by symptoms, sputum GeneXpert® Ultra, smear and culture, radiological features, response to TB therapy and presence of an alternative diagnosis. The study will be conducted in research sites in South Africa, Uganda, The Gambia and Vietnam which all have high TB prevalence. The two-phase design allows for finalisation of the MBT in Phase 1 in which candidate host proteins will be evaluated on stored serum from Asia, South Africa and South America and on fingerstick blood from 50 newly recruited participants per site. The MBT test will then be locked down and validated in Phase 2 on 250 participants per site. DISCUSSION: By targeting confirmatory TB testing to those with a positive triage test, 75% of negative GXPU may be avoided, thereby reducing diagnostic costs and patient losses during the care cascade. This study builds on previous biomarker research and aims to identify a point-of-care test meeting or exceeding the minimum World Health Organisation target product profile of a 90% sensitivity and 70% specificity. Streamlining TB testing by identifying individuals with a high likelihood of TB should improve TB resources use and, in so doing, improve TB care. TRIAL REGISTRATION: NCT04232618 (clinicaltrials.gov) Date of registration: 16 January 2020.


Assuntos
Mycobacterium tuberculosis , Tuberculose , Humanos , Sistemas Automatizados de Assistência Junto ao Leito , Triagem , Tuberculose/diagnóstico , Testes Imediatos , Sensibilidade e Especificidade , Biomarcadores
3.
JAMA ; 329(20): 1745-1756, 2023 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-37219554

RESUMO

Importance: Opioid use for chronic nonmalignant pain can be harmful. Objective: To test whether a multicomponent, group-based, self-management intervention reduced opioid use and improved pain-related disability compared with usual care. Design, Setting, and Participants: Multicentered, randomized clinical trial of 608 adults taking strong opioids (buprenorphine, dipipanone, morphine, diamorphine, fentanyl, hydromorphone, methadone, oxycodone, papaveretum, pentazocine, pethidine, tapentadol, and tramadol) to treat chronic nonmalignant pain. The study was conducted in 191 primary care centers in England between May 17, 2017, and January 30, 2019. Final follow-up occurred March 18, 2020. Intervention: Participants were randomized 1:1 to either usual care or 3-day-long group sessions that emphasized skill-based learning and education, supplemented by 1-on-1 support delivered by a nurse and lay person for 12 months. Main Outcomes and Measures: The 2 primary outcomes were Patient-Reported Outcomes Measurement Information System Pain Interference Short Form 8a (PROMIS-PI-SF-8a) score (T-score range, 40.7-77; 77 indicates worst pain interference; minimal clinically important difference, 3.5) and the proportion of participants who discontinued opioids at 12 months, measured by self-report. Results: Of 608 participants randomized (mean age, 61 years; 362 female [60%]; median daily morphine equivalent dose, 46 mg [IQR, 25 to 79]), 440 (72%) completed 12-month follow-up. There was no statistically significant difference in PROMIS-PI-SF-8a scores between the 2 groups at 12-month follow-up (-4.1 in the intervention and -3.17 in the usual care groups; between-group difference: mean difference, -0.52 [95% CI, -1.94 to 0.89]; P = .15). At 12 months, opioid discontinuation occurred in 65 of 225 participants (29%) in the intervention group and 15 of 208 participants (7%) in the usual care group (odds ratio, 5.55 [95% CI, 2.80 to 10.99]; absolute difference, 21.7% [95% CI, 14.8% to 28.6%]; P < .001). Serious adverse events occurred in 8% (25/305) of the participants in the intervention group and 5% (16/303) of the participants in the usual care group. The most common serious adverse events were gastrointestinal (2% in the intervention group and 0% in the usual care group) and locomotor/musculoskeletal (2% in the intervention group and 1% in the usual care group). Four people (1%) in the intervention group received additional medical care for possible or probable symptoms of opioid withdrawal (shortness of breath, hot flushes, fever and pain, small intestinal bleed, and an overdose suicide attempt). Conclusions and Relevance: In people with chronic pain due to nonmalignant causes, compared with usual care, a group-based educational intervention that included group and individual support and skill-based learning significantly reduced patient-reported use of opioids, but had no effect on perceived pain interference with daily life activities. Trial Registration: isrctn.org Identifier: ISRCTN49470934.


Assuntos
Analgésicos Opioides , Dor Crônica , Transtornos Relacionados ao Uso de Opioides , Feminino , Humanos , Pessoa de Meia-Idade , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/uso terapêutico , Dor Crônica/tratamento farmacológico , Morfina , Transtornos Relacionados ao Uso de Opioides/prevenção & controle , Tramadol , Processos Grupais , Autogestão , Masculino
4.
Clin Infect Dis ; 74(12): 2136-2141, 2022 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34550342

RESUMO

BACKGROUND: The development of a fast and accurate, non-sputum-based point-of-care triage test for tuberculosis (TB) would have a major impact on combating the TB burden worldwide. A new fingerstick blood test has been developed by Cepheid (the Xpert MTB Host Response [MTB-HR] prototype), which generates a "TB score" based on messenger RNA (mRNA) expression of 3 genes. Here we describe the first prospective findings of the MTB-HR prototype. METHODS: Fingerstick blood from adults presenting with symptoms compatible with TB in South Africa, The Gambia, Uganda, and Vietnam was analyzed using the Cepheid GeneXpert MTB-HR prototype. Accuracy of the Xpert MTB-HR cartridge was determined in relation to GeneXpert Ultra results and a composite microbiological score (GeneXpert Ultra and liquid culture) with patients classified as having TB or other respiratory diseases (ORD). RESULTS: When data from all sites (n = 75 TB, 120 ORD) were analyzed, the TB score discriminated between TB and ORD with an area under the curve (AUC) of 0.94 (95% confidence interval [CI], .91-.97), sensitivity of 87% (95% CI, 77-93%) and specificity of 94% (88-97%). When sensitivity was set at 90% for a triage test, specificity was 86% (95% CI, 75-97%). These results were not influenced by human immunodeficiency virus (HIV) status or geographical location. When evaluated against a composite microbiological score (n = 80 TB, 111 ORD), the TB score was able to discriminate between TB and ORD with an AUC of 0.88 (95% CI, .83-.94), 80% sensitivity (95% CI, 76-85%) and 94% specificity (95% CI, 91-96%). CONCLUSIONS: Our interim data indicate the Cepheid MTB-HR cartridge reaches the minimal target product profile for a point of care triage test for TB using fingerstick blood, regardless of geographic area or HIV infection status.


Assuntos
Infecções por HIV , Mycobacterium tuberculosis , Tuberculose , Adulto , Infecções por HIV/diagnóstico , Testes Hematológicos , Humanos , Mycobacterium tuberculosis/genética , Estudos Prospectivos , Sensibilidade e Especificidade , Tuberculose/diagnóstico
5.
BMC Infect Dis ; 22(1): 381, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35428268

RESUMO

BACKGROUND: Natural immunity against Mycobacterium tuberculosis exists, and > 90% of those infected remain disease-free. Innate and adaptive immune responses required to mediate such protection against tuberculosis (TB) are, however, poorly understood. METHODS: This is an analytical study exploring protective and non-protective pathways of immunity against Mycobacterium tuberculosis. Adults without HIV infection are recruited at community healthcare clinics in high TB incidence areas of the Western Cape Province, South Africa. Data regarding participants' medical, social and medication usage will be collected, and clinical examinations and point-of-care tests documented. Reference tests for TB (chest radiographs and sputum tests for GeneXpert MTB/RIF Ultra®, Auramine smear and liquid cultures) and investigations to classify infection states [interferon-gamma release assay (IGRA) and SARS-CoV-2 polymerase chain reaction (PCR) nasopharyngeal swab and IgG], are done on all participants who meet the inclusion criteria. 18F-Fluorodeoxyglucose positron emission tomography combined with computerized tomography will be done on all close contacts (contacts) and healthy control (controls) participants. Participants are divided into 12 study groups representing a spectrum of TB clinical phenotypes and prior SARS-CoV-2 infection based on their TB status, exposure history, results of IGRA test at baseline and 3 months, SARS-CoV-2 serology, and PCR results, and for contacts and controls, PET-CT imaging findings indicative of sub-clinical TB lesions. Samples for experimental assays include whole blood for isolation of peripheral blood mononuclear cells and blood in PAXgene® tubes for RNA isolation. All SARS-CoV-2 PCR negative study participants undergo bronchoscopy for collecting bronchoalveolar lavage samples. DISCUSSION: The paired blood and BAL samples will be used for comprehensive analyses of the tissue-specific and systemic immunity that will include e.g., cytometry by time-of-flight analyses, RNA-sequencing, multiplex immunoassays, epigenetic analysis, and mechanistic studies of control of infection by Mycobacterium tuberculosis. Results will be integrated with those from mice and non-human primate studies to provide a comprehensive analysis of protective pathways in natural and vaccine-induced immunity against Mycobacterium tuberculosis.


Assuntos
COVID-19 , Infecções por HIV , Mycobacterium tuberculosis , Tuberculose dos Linfonodos , Animais , Infecções por HIV/epidemiologia , Humanos , Leucócitos Mononucleares , Camundongos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , RNA , SARS-CoV-2 , África do Sul/epidemiologia
6.
Respiration ; 101(4): 417-421, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34903699

RESUMO

Patients with secondary spontaneous pneumothorax (SSP) complicated by persistent air leak (PAL) and who are poor surgical candidates have limited treatment options. This case series explored autologous blood patch pleurodesis as a possible cost-effective management option. A total of 46 episodes of SSP with PAL were included. The procedure was successful in 33 (71.7%). Of these, 17 (51.5%) resolved within 1 day. The mean duration of intercostal drainage prior to the blood patch was 22 days in the successful group. Pneumothoraces with incomplete lung re-expansion at the time of procedure were successful in 20 of 30 (66.7%). Only human immunodeficiency virus infection was associated with failure (p = 0.03). Adverse events included transient fever (n = 3) that resolved spontaneously, and empyema (n = 3) which were successfully managed with antibiotics and pigtail drainage. We conclude that a large proportion of patients with SSP complicated by PAL who are unfit for surgery may be liberated from intercostal drainage by an autologous blood patch pleurodesis, with minimal adverse effects.


Assuntos
Empiema , Pneumotórax , Drenagem , Humanos , Pulmão , Pleurodese/métodos , Pneumotórax/cirurgia , Pneumotórax/terapia
7.
Am J Physiol Lung Cell Mol Physiol ; 321(3): L566-L575, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34287085

RESUMO

The influence of smoke-derived or air pollution-derived cytoplasmic particulate matter (PM) can be detrimental and can lead to failed lung immunity. We investigated mycobacterial uptake, intracellular replication, and soluble immune-mediator responses of human bronchoalveolar lavage cells (BALCs) loaded with/without PM, to infection with mycobacterial strains. We observed that only BALCs containing PM display an ex vivo phenotypic profile dominated by spontaneous interleukin (IL)-10 production. PM-loaded BALCs retained the ability to phagocytose both Mycobacterium bovis Bacille Calmette Guérin (BCG) and Mycobacterium tuberculosis (M.tb) ΔleuDΔpanCD at equal efficacy as clear non-PM-loaded BALCs. However, immune responsiveness, such as the production of IL-6 (P = 0.015) and tumor necrosis factor-α (TNF)-α (P = 0.0172) immediately post M. bovis BCG infection, were dramatically lower in black BALCs loaded with PM versus clear non-PM-loaded BALCs. By 24 h post infection, differential immune responses to M. bovis BCG between black versus clear BALC waned, and instead, production of IL-6 (P = 0.03) and IL-1α (P = 0.04) by black BALCs was lower versus clear BALCs following M.tb ΔleuDΔpanCD infection. Considering that TNF-α and IL-6 are characterized as critical to host protection against mycobacteria, our findings suggest that BALCs loaded with inhaled PM, display lower levels of antimycobacterial mediators and that the response magnitude differs according to infective mycobacterial strain. Even though this did not translate into altered mycobacterial killing at early time points post infection, the long-term impact of such changes remains to be established.


Assuntos
Exposição por Inalação/efeitos adversos , Pulmão/imunologia , Mycobacterium bovis/imunologia , Mycobacterium tuberculosis/imunologia , Material Particulado/efeitos adversos , Fagócitos/imunologia , Líquido da Lavagem Broncoalveolar , Feminino , Humanos , Pulmão/microbiologia , Pulmão/patologia , Masculino , Monocinas/imunologia , Fagócitos/microbiologia , Fagócitos/patologia
8.
Respiration ; 100(1): 59-63, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33333531

RESUMO

In high-burden settings, the diagnosis of pleural tuberculosis (TB) is frequently inferred in patients who present with lymphocyte predominant exudative effusions and high adenosine deaminase (ADA) levels. Two recent small retrospective studies suggested that the lactate dehydrogenase (LDH)/ADA ratio is significantly lower in TB than in non-TB pleural effusions and that the LDH/ADA ratio may be useful in differentiating pleural TB from other pleural exudates. We compared the pleural LDH/ADA ratios, ADA levels, and lymphocyte predominance of a prospectively collected cohort of patients with proven pleural TB (n = 160) to those with a definitive alternative diagnosis (n = 68). The mean pleural fluid LDH/ADA ratio was lower in patients with pleural TB than alternative diagnoses (6.2 vs. 34.3, p < 0.001). The area under the receiver operating characteristic curve was 0.92 (p < 0.001) for LDH/ADA ratio and 0.88 (p < 0.001) for an ADA ≥40 U/L alone. A ratio of ≤12.5 had the best overall diagnostic efficiency, while a ratio of ≤10 had a specificity of 90% and a positive predictive value of 95%, with a sensitivity of 78%, making it a clinically useful "rule in" value for pleural TB in high incidence settings. When comparing the LDH/ADA ratio to an ADA level ≥40 U/L in the presence of a lymphocyte predominant effusion, the latter performed better. When lymphocyte values are unavailable, our data suggest that the LDH/ADA ratio is valuable in distinguishing TB effusions from other pleural exudates.


Assuntos
Adenosina Desaminase/análise , L-Lactato Desidrogenase/análise , Linfócitos , Derrame Pleural , Tuberculose Pleural , Contagem de Células/métodos , Regras de Decisão Clínica , Diagnóstico Diferencial , Exsudatos e Transudatos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Derrame Pleural/diagnóstico , Derrame Pleural/metabolismo , Derrame Pleural/microbiologia , Valor Preditivo dos Testes , Curva ROC , Sensibilidade e Especificidade , Tuberculose Pleural/complicações , Tuberculose Pleural/diagnóstico
9.
Lancet Oncol ; 21(8): e375-e385, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32758475

RESUMO

The aims of the Oncoplastic Breast Consortium initiative were to identify important knowledge gaps in the field of oncoplastic breast-conserving surgery and nipple-sparing or skin-sparing mastectomy with immediate breast reconstruction, and to recommend appropriate research strategies to address these gaps. A total of 212 surgeons and 26 patient advocates from 55 countries prioritised the 15 most important knowledge gaps from a list of 38 in two electronic Delphi rounds. An interdisciplinary panel of the Oncoplastic Breast Consortium consisting of 63 stakeholders from 20 countries obtained consensus during an in-person meeting to select seven of these 15 knowledge gaps as research priorities. Three key recommendations emerged from the meeting. First, the effect of oncoplastic breast-conserving surgery on quality of life and the optimal type and timing of reconstruction after nipple-sparing or skin-sparing mastectomy with planned radiotherapy should be addressed by prospective cohort studies at an international level. Second, the role of adjunctive mesh and the positioning of implants during implant-based breast reconstruction should ideally be investigated by randomised controlled trials of pragmatic design. Finally, the BREAST-Q questionnaire is a suitable tool to assess primary outcomes in these studies, but other metrics to measure patient-reported outcomes should be systematically evaluated and quality indicators of surgical morbidity should be further assessed.


Assuntos
Neoplasias da Mama/cirurgia , Mamoplastia , Feminino , Humanos
10.
Curr Opin Pulm Med ; 26(5): 373-383, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32701672

RESUMO

PURPOSE OF REVIEW: Pulmonary hypertension is a deadly disease, the causes of which vary between geographical regions. Eighty four percentage of the world's population lives in majority countries (also called low-income and middle-income countries), yet data on pulmonary hypertension in these settings are proportionally scarce. This article provides a review of pulmonary hypertension in majority countries, focusing in detail on the most common causes in these regions, and highlights contextual challenges faced. RECENT FINDINGS: Epidemiological data confirms a complex and overlapping array of causes, with pulmonary hypertension because of conditions such as rheumatic heart disease, HIV, schistosomiasis, chronic lung disease and sickle cell disease. Delayed pulmonary hypertension diagnosis remains a concern and is ascribed to a lack of resources and lack of pulmonary hypertension awareness by health professionals. Pulmonary hypertension diagnosis is frequently considered once signs of right heart failure emerge, while echocardiography and right heart catheterization are unavailable in many settings. Accurate data on the prevalence of pulmonary hypertension in many of these regions are needed and could be achieved by establishing and frequent review of national databases where the incident and prevalent pulmonary hypertension cases are captured. SUMMARY: There is urgent need for pulmonary hypertension advocacy among clinicians in the primary, secondary and tertiary healthcare sectors of majority countries, and validated noninvasive diagnostic algorithms are needed. Increased awareness and early diagnosis are likely to improve outcomes of pulmonary hypertension patients in these regions, and potentially stimulate locally relevant research.


Assuntos
Países em Desenvolvimento , Hipertensão Pulmonar/epidemiologia , Hipertensão Pulmonar/etiologia , Anemia Falciforme/complicações , Infecções por HIV/complicações , Humanos , Hipertensão Pulmonar/diagnóstico , Pneumopatias/complicações , Prevalência , Cardiopatia Reumática/complicações , Esquistossomose/complicações
11.
New Phytol ; 224(1): 439-453, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31215645

RESUMO

In addition to well-known roles in RNA metabolism, the nucleolus and Cajal bodies (CBs), both located within the nucleus, are involved in plant responses to biotic and abiotic stress. Previously we showed that plants in which expression of the CB protein coilin is downregulated are more susceptible to certain viruses including tobacco rattle virus (TRV), suggesting a role of coilin in antiviral defence. Experiments with coilin-deficient plants and the deletion mutant of the TRV 16K protein showed that both 16K and coilin are required for restriction of systemic TRV infection. The potential mechanisms of coilin-mediated antiviral defence were elucidated via experiments involving co-immunoprecipitation, use of NahG transgenic plants deficient in salicylic acid (SA) accumulation, measurement of endogenous SA concentrations and assessment of SA-responsive gene expression. Here we show that TRV 16K interacts with and relocalizes coilin to the nucleolus. In wild-type plants these events are accompanied by activation of SA-responsive gene expression and restriction of TRV systemic infection. By contrast, viral systemic spread was enhanced in NahG plants, implicating SA in these processes. Our findings suggest that coilin is involved in plant defence, responding to TRV infection by recognition of the TRV-encoded 16K protein and activating SA-dependent defence pathways.


Assuntos
Corpos Enovelados/metabolismo , Nicotiana/imunologia , Nicotiana/virologia , Proteínas Nucleares/metabolismo , Proteínas de Plantas/metabolismo , Vírus de Plantas/fisiologia , Ácido Salicílico/metabolismo , Proteínas Virais/metabolismo , Regulação da Expressão Gênica de Plantas , Plantas Geneticamente Modificadas , Ligação Proteica , Nicotiana/genética
12.
Plant Cell ; 28(10): 2586-2602, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27702772

RESUMO

RNA trafficking plays pivotal roles in regulating plant development, gene silencing, and adaptation to environmental stress. Satellite RNAs (satRNAs), parasites of viruses, depend on their helper viruses (HVs) for replication, encapsidation, and efficient spread. However, it remains largely unknown how satRNAs interact with viruses and the cellular machinery to undergo trafficking. Here, we show that the P20 protein of Bamboo mosaic potexvirus satRNA (satBaMV) can functionally complement in trans the systemic trafficking of P20-defective satBaMV in infected Nicotiana benthamiana The transgene-derived satBaMV, uncoupled from HV replication, was able to move autonomously across a graft union identified by RT-qPCR, RNA gel blot, and in situ RT-PCR analyses. Coimmunoprecipitation experiments revealed that the major nucleolar protein fibrillarin is coprecipitated in the P20 protein complex. Notably, silencing fibrillarin suppressed satBaMV-, but not HV-, phloem-based movement following grafting or coinoculation with HV Confocal microscopy revealed that the P20 protein colocalized with fibrillarin in the nucleoli and formed punctate structures associated with plasmodesmata. The mobile satBaMV RNA appears to exist as ribonucleoprotein (RNP) complex composed of P20 and fibrillarin, whereas BaMV movement proteins, capsid protein, and BaMV RNA are recruited with HV coinfection. Taken together, our findings provide insight into movement of satBaMV via the fibrillarin-satBaMV-P20 RNP complex in phloem-mediated systemic trafficking.


Assuntos
Vírus Auxiliares/genética , RNA de Plantas/genética , RNA Satélite/genética , Ribonucleoproteínas/metabolismo , Proteínas Virais/genética , Imunoprecipitação , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Respirology ; 24(10): 962-971, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31418985

RESUMO

Tuberculous effusion is a common disease entity with a spectrum of presentations from a largely benign effusion, which resolves completely, to a complicated effusion with loculations, pleural thickening and even frank empyema, all of which may have a lasting effect on lung function. The pathogenesis is a combination of true pleural infection and an effusive hypersensitivity reaction, compartmentalized within the pleural space. Diagnostic thoracentesis with thorough pleural fluid analysis including biomarkers such as adenosine deaminase and gamma interferon achieves high accuracy in the correct clinical context. Definitive diagnosis may require invasive procedures to demonstrate histological evidence of caseating granulomas or microbiological evidence of the organism on smear or culture. Drug resistance is an emerging problem that requires vigilance and extra effort to acquire a complete drug sensitivity profile for each tuberculous effusion treated. Nucleic acid amplification tests such as Xpert MTB/RIF can be invaluable in this instance; however, the yield is low in pleural fluid. Treatment consists of standard anti-tuberculous therapy or a guideline-based individualized regimen in the case of drug resistance. There is low-quality evidence that suggests possible benefit from corticosteroids; however, they are not currently recommended due to concomitant increased risk of adverse effects. Small studies report some short- and long-term benefit from interventions such as therapeutic thoracentesis, intrapleural fibrinolytics and surgery but many questions remain to be answered.


Assuntos
Antituberculosos/uso terapêutico , Derrame Pleural/tratamento farmacológico , Tuberculose Pleural/diagnóstico , Tuberculose Pleural/terapia , Adenosina Desaminase/análise , Líquidos Corporais/química , Farmacorresistência Bacteriana , Humanos , Interferon gama/análise , Derrame Pleural/microbiologia , Toracentese , Tuberculose Pleural/complicações
14.
New Phytol ; 218(3): 1167-1178, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28407256

RESUMO

Peptide hormones are implicated in many important aspects of plant life and are usually synthesized as precursor proteins. In contrast to animals, data for plant peptide hormone maturation are scarce and the specificity of processing enzyme(s) is largely unknown. Here we tested a hypothesis that processing of prosystemin, a precursor of tomato (Solanum lycopersicum) wound hormone systemin, is performed by phytaspases, aspartate-specific proteases of the subtilase family. Following the purification of phytaspase from tomato leaves, two tomato phytaspase genes were identified, the cDNAs were cloned and the recombinant enzymes were obtained after transient expression in Nicotiana benthamiana. The newly identified tomato phytaspases hydrolyzed prosystemin at two aspartate residues flanking the systemin sequence. Site-directed mutagenesis of the phytaspase cleavage sites in prosystemin abrogated not only the phytaspase-mediated processing of the prohormone in vitro, but also the ability of prosystemin to trigger the systemic wound response in vivo. The data show that the prohormone prosystemin requires processing for signal biogenesis and biological activity. The identification of phytaspases as the proteases involved in prosystemin maturation provides insight into the mechanisms of wound signaling in tomato. Our data also suggest a novel role for cell death-related proteases in mediating defense signaling in plants.


Assuntos
Ácido Aspártico Endopeptidases/metabolismo , Peptídeos/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Precursores de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Solanum lycopersicum/metabolismo , Hidrólise , Transdução de Sinais
15.
J Vet Med Educ ; 44(1): 187-197, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28206846

RESUMO

This case study sought to understand veterinary students' perceptions and experiences of the Healer's Art (HART) elective to support well-being and resilience. Students' "mindful attention" was assessed using the MAAS-State scale. Course evaluations and written materials for course exercises (artifacts) across the 2012-2015 cohorts of Colorado State University's HART veterinary students (n=99) were analyzed for themes using a grounded theory approach, followed by thematic comparison with analyses of HART medical student participants. HART veterinary students described identity/self-expression and spontaneity/freedom as being unwelcome in the veterinary curriculum, whereas HART medical students described spirituality as unwelcome. HART veterinary students identified issues of "competition" and "having no time," which were at odds with their descriptions of not competing and having the time to connect with self and peers within their HART small groups. HART veterinary students shared that the course practices of nonjudgment, generous listening, and presence (i.e., mindfulness practices) helped them build relationships with peers. Although not statistically significant, MAAS pre-/post-scores trended in the positive direction. HART provides opportunities for students to connect with self and foster bonds with peers and the profession, factors that are positively associated with resilience and wellness.


Assuntos
Currículo , Educação em Veterinária , Grupo Associado , Estudantes de Medicina/psicologia , Estudos de Coortes , Colorado , Humanos , Faculdades de Medicina Veterinária , Adulto Jovem
16.
J Vet Med Educ ; 44(1): 63-71, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28206845

RESUMO

Clinical empathy is a multi-dimensional concept characterized by four dimensions: (1) affective-the ability to experience patients' or clients' emotions and perspectives, (2) moral-the internal motivation to empathize, (3) cognitive-the intellectual ability to identify and comprehend others' perspective and emotions, and (4) behavioral-the ability to convey understanding of those emotions and perspectives back to the patient or client. The Davis Interpersonal Reactivity Index (IRI) was used to examine the affective and cognitive facets of empathy in veterinary practitioners. The IRI consists of four subscales that measure cognitive (perspective taking and fantasy) and affective (emphatic concern and personal distress) components of empathy. Data from a cross-sectional sample of practicing veterinarians (n=434) were collected. Veterinarians' fantasy scores were lowest for those with the most clinical experience. Personal distress scores were highest among new veterinarians and lowest for those with 26 or more years in practice. High levels of personal distress in the early years of practice are concerning for the professional wellness of veterinarians. To combat this trend, the implementation of resilience-building interventions should be considered to support veterinary practitioners.


Assuntos
Empatia , Médicos Veterinários/psicologia , Adulto , Idoso , Cognição , Colorado , Estudos Transversais , Emoções , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , North Carolina , Adulto Jovem
19.
J Vet Med Educ ; 42(3): 194-205, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26075622

RESUMO

Empathy can be defined as the ability to understand and connect with the emotional state and frame of mind of another. Establishing connections with others is a crucial skill for veterinarians who must earn the trust and compliance of their clients to provide quality care for their patients. This is a longitudinal study using the Davis Interpersonal Reactivity Index (IRI) to assess changes in veterinary students' self-reported empathy as they progressed through the didactic portion of the DVM program at Colorado State University. The IRI consists of four subscales that measure cognitive and affective components of empathy: Perspective Taking, Fantasy, Emphatic Concern, and Personal Distress. Data were collected at three time points, corresponding to the start of the first year, the fourth semester (second year), and the fifth semester (third year). Results showed an overall decline in Perspective Taking scores, with a significant decrease between first and second year. There was an overall increase in students' levels of Personal Distress as they progressed through the program. The significant difference was found between years 1 and 3. This is especially concerning because the enhanced unease in interpersonal interactions coincides with students entering clinical rotations in the third year-the very time when these traits are necessary for quality client and patient care. Veterinary educators are urged to use this information as a basis for investigating novel curricular and programmatic interventions to counteract these changes in student empathy.


Assuntos
Empatia , Estudantes/psicologia , Adulto , Educação em Veterinária , Feminino , Humanos , Estudos Longitudinais , Masculino , Autorrelato , Ensino , Adulto Jovem
20.
EMBO J ; 29(6): 1149-61, 2010 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-20111004

RESUMO

Caspases are cysteine-dependent proteases and are important components of animal apoptosis. They introduce specific breaks after aspartate residues in a number of cellular proteins mediating programmed cell death (PCD). Plants encode only distant homologues of caspases, the metacaspases that are involved in PCD, but do not possess caspase-specific proteolytic activity. Nevertheless, plants do display caspase-like activities indicating that enzymes structurally distinct from classical caspases may operate as caspase-like proteases. Here, we report the identification and characterisation of a novel PCD-related subtilisin-like protease from tobacco and rice named phytaspase (plant aspartate-specific protease) that possesses caspase specificity distinct from that of other known caspase-like proteases. We provide evidence that phytaspase is synthesised as a proenzyme, which is autocatalytically processed to generate the mature enzyme. Overexpression and silencing of the phytaspase gene showed that phytaspase is essential for PCD-related responses to tobacco mosaic virus and abiotic stresses. Phytaspase is constitutively secreted into the apoplast before PCD, but unexpectedly is re-imported into the cell during PCD providing insights into how phytaspase operates.


Assuntos
Caspases/metabolismo , Peptídeo Hidrolases/metabolismo , Proteínas de Plantas/metabolismo , Caspases/química , Caspases/genética , Morte Celular , Células Cultivadas , Oryza/genética , Oryza/metabolismo , Peptídeo Hidrolases/análise , Peptídeo Hidrolases/genética , Proteínas de Plantas/química , Plantas Geneticamente Modificadas , Especificidade por Substrato , Nicotiana/genética , Nicotiana/metabolismo
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