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1.
Antimicrob Agents Chemother ; 68(3): e0127923, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38299818

RESUMO

Invasive primary Candida surgical site infections (IP-SSIs) are a common complication of liver transplantation, and targeted antifungal prophylaxis is an efficient strategy to limit their occurrence. We performed a retrospective single-center cohort study among adult single liver transplant recipients at Duke University Hospital in the period between 1 January 2015 and 31 December 2020. The study aimed to determine the rate of Candida IP-SSI according to the peri-transplant antifungal prophylaxis received. Of 470 adult single liver transplant recipients, 53 (11.3%) received micafungin prophylaxis, 100 (21.3%) received fluconazole prophylaxis, and 317 (67.4%) did not receive systemic antifungal prophylaxis in the peri-transplant period. Ten Candida IP-SSIs occurred among 5 of 53 (9.4%) micafungin recipients, 1 of 100 (1.0%) fluconazole recipients, and 4 of 317 (1.3%) recipients who did not receive antifungal prophylaxis. Our study highlights the limitations of antifungal prophylaxis in preventing invasive Candida IP-SSI after liver transplant surgery. We hypothesize that pathogen, host, and pharmacokinetic-related factors contributed to the occurrence of Candida IP-SSI despite antifungal prophylaxis. Our study reinforces the need for a risk-based, multi-pronged approach to fungal prevention, including targeted antifungal administration in patients with risks for invasive candidiasis and close monitoring, especially among patients with surgically complex procedures, with timely control of surgical leaks.


Assuntos
Candidíase Invasiva , Candidíase , Transplante de Fígado , Adulto , Humanos , Antifúngicos/uso terapêutico , Fluconazol/uso terapêutico , Transplante de Fígado/efeitos adversos , Micafungina/uso terapêutico , Estudos Retrospectivos , Estudos de Coortes , Infecção da Ferida Cirúrgica/prevenção & controle , Infecção da Ferida Cirúrgica/tratamento farmacológico , Candidíase Invasiva/tratamento farmacológico , Candidíase Invasiva/prevenção & controle , Candida
2.
Georgian Med News ; (347): 149-150, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38609132

RESUMO

Traditionally, it was believed that both proximal and distal locking are essential for achieving stability during intra-medullary fixation for extra-capsular hip fractures. However, recent literature has presented varying perspectives on the necessity of distal locking. Distal locking plays a significant role in managing hip fractures with uncertainties regarding longitudinal and rotational stability. This includes cases of comminuted intertrochanteric fractures with subtrochanteric extension, reverse oblique and high oblique fractures, broad medullary canals, comminution of the lateral wall, diaphyseal fractures, and large posteromedial fragments extending below the level of the lesser trochanter. In stable pertrochanteric fractures, with the lag screw passing through the lateral cortex of the distal fragment, may not require a distal locking screw. Distal locking has been associated with potential complications, including irritation of the fascia lata, prolonged operation time, increased radiation exposure, greater blood loss, implant loosening, secondary femoral stress fractures, and damage to the femoral artery. Thus, although distal locking is of doubtful significance in stable pertrochanteric fractures it is essential in unstable fracture patterns.


Assuntos
Fraturas do Fêmur , Fixação Intramedular de Fraturas , Fraturas do Quadril , Humanos , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/cirurgia , Parafusos Ósseos , Artéria Femoral
3.
Georgian Med News ; (347): 122-124, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38609127

RESUMO

Fractures of the metacarpal particularly the 5th metacarpal is quite common among all hand fractures and has a high incidence in male adult population. Proper management of these fractures plays a key role in rehabilitation and early return to work thus reducing the economic burden. Treatment of these injuries depends on the type of injury: whether it is a closed/open fracture, degree of angulation at the fracture site and also mal-rotation and shortening of the finger. Non-operative management is suitable for fractures which are closed, non-displaced and without angulation or rotation. Open fractures, fractures with angulation and/or mal-rotation and fractures with neuro-vascular injury are more suitable for operative management. The acceptable angulation for conservative management for most studies is 70 degrees. Buddy strapping with a Futura splint provides good functional results. In fractures requiring operative intervention, K-wire fixation is a minimally invasive method of fixation, which in most cases has good functional results. Plate and screw fixation, however, is preferred for cases with significant comminution or multiple metacarpal fractures.


Assuntos
Fraturas Fechadas , Fraturas Expostas , Adulto , Humanos , Masculino , Parafusos Ósseos , Tratamento Conservador
4.
Indian J Med Res ; 156(6): 750-755, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-37056074

RESUMO

Background & objectives: As per national guidelines, prospective blood donors with a history of jaundice of unknown cause are deferred permanently to prevent the transmission of hepatitis B and C. The validity of this guideline was tested by comparing prevalence rates of hepatitis B and C in prospective blood donors deferred due to a history of jaundice, with that of donors who were found fit. Methods: Blood samples of 212 consecutive donors (male, n=203) deferred due to a history of jaundice were studied for hepatitis B and C by rapid test kits as well as by chemiluminescence (n=115) or ELISA (n=97). Consecutive healthy donors (n=549; male, n=518) were also studied by ELISA (n=266) or chemiluminescence (n=283). Results: The cumulative prevalence detected by rapid test kit and ELISA/chemiluminescence tests of hepatitis B (n=10) and C (n=2) among donors deferred due to a history of jaundice (n=212) was 5.7 per cent [95% confidence interval (CI): 2.9, 9.9]. The prevalence of reactive results among healthy donors (n=549) by ELISA/chemiluminescence tests was 3.3 per cent (95% CI: 1.9, 5.2), which included hepatitis B (n=15) and hepatitis C (n=3) cases. Compared to healthy donors, the odds of seropositivity among jaundice-deferred donors was 1.7 (95% CI: 0.8, 3.6), P=0.15. For rapid test-negative deferred donors, the odds of seropositivity by ELISA/chemiluminescence declined to 0.4 (0.1, 1.5), P=0.19. Interpretation & conclusions: The prevalence rates of hepatitis B and C in prospective blood donors deferred due to a history of jaundice of unknown aetiology did not differ significantly from that in healthy donors. The current practice of permanently deferring such donors depletes valuable donor pool. A strategy of rejecting only those donors who are found reactive on pre-donation testing by rapid test needs further validation.


Assuntos
Hepatite B , Hepatite C , Icterícia , Masculino , Humanos , Doadores de Sangue , Prevalência , Estudos Prospectivos , Hepatite C/complicações , Hepatite C/epidemiologia , Hepatite B/complicações , Hepatite B/epidemiologia , Hepatite B/prevenção & controle , Icterícia/epidemiologia , Antígenos de Superfície da Hepatite B
5.
Acta Neurochir (Wien) ; 164(5): 1287-1292, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35067784

RESUMO

Carotid-cavernous fistulas (CCFs) are abnormal vascular shunts between the carotid artery and the cavernous sinus. A 37-year-old male presented with a traumatic CCF and basal skull fracture extending through the medial wall of the cavernous sinus and sphenoid sinus. The CCF was treated with endovascular coiling. Three months after this procedure, he was found to have coil migration through the traumatic sphenoid defect into the pharynx. He underwent urgent endonasal endoscopic surgery to disconnect and remove the extruded coil. Post-operative coil migration is a rare but serious complication following endovascular treatment of traumatic CCF.


Assuntos
Fístula Carótido-Cavernosa , Seio Cavernoso , Embolização Terapêutica , Adulto , Fístula Carótido-Cavernosa/diagnóstico por imagem , Fístula Carótido-Cavernosa/etiologia , Fístula Carótido-Cavernosa/cirurgia , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/métodos , Humanos , Masculino , Orofaringe , Osso Esfenoide
6.
Br J Cancer ; 122(12): 1760-1768, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32350413

RESUMO

BACKGROUND: Nab-paclitaxel plus gemcitabine (nabP+gemcitabine) offers modest survival gains for patients with metastatic pancreatic ductal adenocarcinoma (PDAC). Sequential scheduling of nabP+gemcitabine in a PDAC mouse model improved efficacy; this hypothesis was tested in a clinical trial. METHODS: Patients with previously untreated metastatic PDAC were randomised to receive nabP+gemcitabine administered either concomitantly on the same day, or sequentially, with gemcitabine administered 24 h after nabP. The primary outcome measure was progression-free survival (PFS). Secondary outcome measures were objective response rate (ORR), overall survival (OS), safety, quality of life (QoL) and predictive biomarkers. RESULTS: In total, 71 patients received sequential (SEQ) and 75 concomitant (CON) treatment. Six-month PFS was 46% with SEQ and 32% with CON scheduling. Median PFS (5.6 versus 4.0 months, hazard ratio [HR] 0.67, 95% confidence interval [95% CI] 0.47-0.95, p = 0.022) and ORR (52% versus 31%, p = 0.023) favoured the SEQ arm; median OS was 10.2 versus 8.2 months (HR 0.93, 95% CI 0.65-1.33, p = 0.70). CTCAE Grade ≥3 neutropaenia incidence doubled with SEQ therapy but was not detrimental to QoL. Strongly positive tumour epithelial cytidine deaminase (CDA) expression favoured benefit from SEQ therapy (PFS HR 0.31, 95% CI 0.13-0.70). CONCLUSIONS: SEQ delivery of nabP+gemcitabine improved PFS and ORR, with manageable toxicity, but did not significantly improve OS. CLINICAL TRIAL REGISTRATION: ISRCTN71070888; ClinialTrials.gov (NCT03529175).


Assuntos
Albuminas/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma Ductal Pancreático/tratamento farmacológico , Desoxicitidina/análogos & derivados , Paclitaxel/administração & dosagem , Neoplasias Pancreáticas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Carcinoma Ductal Pancreático/mortalidade , Desoxicitidina/administração & dosagem , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Intervalo Livre de Progressão , Gencitabina , Neoplasias Pancreáticas
7.
J Struct Biol ; 199(3): 165-176, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28705712

RESUMO

Diadenosine polyphosphates (ApnA, n=2-6), particularly Ap4A, are involved in several important physiological processes. The substantial sequence identity of the Nudix hydrolase domain (domain 1) of Mycobacterium smegmatis MutT1 (MsMutT1) with a known Ap4A hydrolase suggested that MsMutT1 could also hydrolyse diadenosine polyphosphates. Biochemical experiments yielded results in conformity with this suggestion, with Ap4A as the best among the substrates. ATP is a product in all experiments; small amounts of ADP were also observed in the experiments involving Ap4A and Ap6A. Hydrolysis was inhibited by fluoride ions in all cases. The mechanism of action and its inhibition in relation to ApnA were explored through the X-ray analysis of the crystals of the MsMutT1 complexes with Ap5A; Ap5A and MnCl2; Ap4A; ATP; and ATP.NaF.MgCl2. The aggregation pattern of molecules in the first four crystals is similar to that found in a majority of MsMutT1-NTP crystals. Substrate molecules occupy the primary binding site and ATP occupies a site at an intermolecular interface, in the first two. ATP occupies both the sites in the third and fourth crystal. The protein-ligand interactions observed in these crystal structures lead to an explanation of the molecular mechanism of hydrolysis of ApnA by MsMutT1. The fifth crystal exhibits a new packing arrangement. The structure of the complex provides an explanation for the fluoride inhibition of the activity of the enzyme. It would thus appear that MutT1 has a major role involving the hydrolysis of diadenosine polyphosphates, which could be elucidated at the molecular level.


Assuntos
Hidrolases Anidrido Ácido/química , Hidrolases Anidrido Ácido/metabolismo , Fosfatos de Dinucleosídeos/metabolismo , Mycobacterium smegmatis/enzimologia , Difosfato de Adenosina/química , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/química , Trifosfato de Adenosina/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Sítios de Ligação , Cristalografia por Raios X , Fosfatos de Dinucleosídeos/química , Hidrólise , Modelos Moleculares , Polifosfatos/química , Polifosfatos/metabolismo , Conformação Proteica
8.
Diabet Med ; 34(3): 419-425, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27151105

RESUMO

AIM: To examine the hypothesis that the quality, magnitude and breadth of helper T-lymphocyte responses to ß cells differ in Type 1 diabetes according to diagnosis in childhood or adulthood. METHODS: We studied helper T-lymphocyte reactivity against ß-cell autoantigens by measuring production of the pro-inflammatory cytokine interferon-γ and the anti-inflammatory cytokine interleukin-10, using enzyme-linked immunospot assays in 61 people with Type 1 diabetes (within 3 months of diagnosis, positive for HLA DRB1*0301 and/or *0401), of whom 33 were children/adolescents, and a further 91 were unaffected siblings. RESULTS: Interferon-γ responses were significantly more frequent in children with Type 1 diabetes compared with adults (85 vs 61%; P = 0.04). Insulin and proinsulin peptides were preferentially targeted in children (P = 0.0001 and P = 0.04, respectively) and the breadth of the interferon-γ response was also greater, with 70% of children having an interferon-γ response to three or more peptides compared with 14% of adults (P < 0.0001). Islet ß-cell antigen-specific interleukin-10 responses were similar in children and adults in terms of frequency, breadth and magnitude, with the exception of responses to glutamic acid decarboxylase 65, which were significantly less frequent in adults. CONCLUSIONS: At diagnosis of Type 1 diabetes, pro-inflammatory autoreactivity is significantly more prevalent, focuses on a wider range of targets, and is more focused on insulin/proinsulin in children than adults. We interpret this as indicating a more aggressive immunological response in the younger age group that is especially characterized by loss of tolerance to proinsulin. These findings highlight the existence of age-related heterogeneity in Type 1 diabetes pathogenesis that could have relevance to the development of immune-based therapies.


Assuntos
Envelhecimento , Autoimunidade , Linfócitos T CD4-Positivos/metabolismo , Diabetes Mellitus Tipo 1/imunologia , Células Secretoras de Insulina/imunologia , Modelos Imunológicos , Adolescente , Adulto , Autoanticorpos/análise , Autoantígenos/metabolismo , Linfócitos T CD4-Positivos/imunologia , Criança , Pré-Escolar , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 1/metabolismo , Feminino , Humanos , Células Secretoras de Insulina/metabolismo , Testes de Liberação de Interferon-gama , Interleucina-10/metabolismo , Masculino , Irmãos , Adulto Jovem
9.
Nanotechnology ; 28(42): 423001, 2017 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-28762339

RESUMO

Exploring and making predictions based on single-molecule data can be challenging, not only due to the sheer size of the datasets, but also because a priori knowledge about the signal characteristics is typically limited and poor signal-to-noise ratio. For example, hypothesis-driven data exploration, informed by an expectation of the signal characteristics, can lead to interpretation bias or loss of information. Equally, even when the different data categories are known, e.g., the four bases in DNA sequencing, it is often difficult to know how to make best use of the available information content. The latest developments in machine learning (ML), so-called deep learning (DL) offer interesting, new avenues to address such challenges. In some applications, such as speech and image recognition, DL has been able to outperform conventional ML strategies and even human performance. However, to date DL has not been applied much in single-molecule science, presumably in part because relatively little is known about the 'internal workings' of such DL tools within single-molecule science as a field. In this Tutorial, we make an attempt to illustrate in a step-by-step guide how one of those, a convolutional neural network (CNN), may be used for base calling in DNA sequencing applications. We compare it with a SVM as a more conventional ML method, and discuss some of the strengths and weaknesses of the approach. In particular, a 'deep' neural network has many features of a 'black box', which has important implications on how we look at and interpret data.

10.
Cell Mol Biol (Noisy-le-grand) ; 63(2): 1-8, 2017 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-28364793

RESUMO

Overwhelmingly increasing scientific evidence has provided near complete resolution of prostate cancer landscape and it is now more understandable that wide ranging factors underlies its development and progression. Increasingly it is being realized that genetic/epigenetic factors, Intra-tumoral and inter-tumoral heterogeneity, loss of apoptosis, dysregulations of spatio-temporally controlled signaling cascades, Darwinian evolution in response to therapeutic pressures play instrumental role in prostate carcinogenesis. Moreover, multi-directional patterns of spread between primary tumors and metastatic sites have also been studied extensively in prostate cancer. Research over the years has gradually and systematically revealed closer association between tumor phenotype and type of gene fusion. Latest developments in deep sequencing technologies have shown that gene fusions originate in a non-random, cell type dependent manner and are much more frequent than previously surmised. These findings enabled sub-classification and categorization of seemingly identical diseases. Furthermore, research methodologies have shown that many gene fusions inform us about risk stratification and many chimeric proteins encoded by the fused genes are being studied as drug target/s. We partition this multi-component review into the molecular basis of formation of fusion transcripts, how protein network is regulated in fusion positive prostate cancer cells and therapeutic strategies which are currently being investigated to efficiently target fusion transcript and its protein product.


Assuntos
Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Proteínas de Fusão Oncogênica/genética , Neoplasias da Próstata/genética , Transdução de Sinais/genética , Apoptose/genética , Reparo do DNA por Junção de Extremidades/genética , Humanos , Masculino , Modelos Genéticos , Proteínas de Fusão Oncogênica/metabolismo , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/metabolismo
11.
J Nanosci Nanotechnol ; 17(4): 2857-860, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29668206

RESUMO

A simple and low cost top­down wet chemical etching method was developed to fabricate hierarchical multi-diameter well-ordered single-crystal silicon nanowires. The procedure starts with forming single diameter silicon nanowire arrays by using nanosphere lithography and metal-assisted chemical etching of single crystal silicon wafer, which is followed by anisotropic radial etching of the wires. Successive repetitions of these etching steps result in arrays of multi-diameter single crystal nanowires. This technique can allow engineering nanowires in a hierarchical three-dimensional geometry for the development of advanced nano devices.

12.
Can Assoc Radiol J ; 68(2): 178-186, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28438285

RESUMO

The interaction between fungi and the sinonasal tract results in a range of clinical presentations with a broad spectrum of clinical severity. The most commonly accepted classification system divides fungal rhinosinusitis into invasive and noninvasive subtypes based on histopathological evidence of tissue invasion by fungi. Invasive fungal rhinosinusitis is subdivided into acute invasive and chronic invasive categories. The chronic invasive category includes a subcategory of chronic granulomatous disease. Noninvasive fungal disease includes localized fungal colonization, fungal ball, and allergic fungal rhinosinusitis. Noninvasive disease is simply fungal material (or the products of the inflammatory reaction of the sinus mucosa) that fills the sinuses but does not invade tissue. Bone loss is related to expansion of the sinus(es). Invasive disease causes tissue destruction, such that it expands past the bony confines of the sinuses. It can rapidly spread, causing acute necrosis. Alternatively, there may be slow tissue invasion characterized by symptoms confused with normal sinusitis, but destruction of normal nasal and paranasal structures.


Assuntos
Micoses/diagnóstico por imagem , Rinite/diagnóstico por imagem , Rinite/microbiologia , Sinusite/diagnóstico por imagem , Sinusite/microbiologia , Humanos , Período Intraoperatório , Imageamento por Ressonância Magnética , Micoses/cirurgia , Rinite/cirurgia , Sinusite/cirurgia , Tomografia Computadorizada por Raios X
13.
Reprod Health ; 13: 16, 2016 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-26916141

RESUMO

BACKGROUND: Postpartum sepsis accounts for most maternal deaths between three and seven days postpartum, when most mothers, even those who deliver in facilities, are at home. Case fatality rates for untreated women are very high. Newborns of ill women have substantially higher infection risk. METHODS/DESIGN: The objectives of this study are to: (1) create, field-test and validate a tool for community health workers to improve diagnostic accuracy of suspected puerperal sepsis; (2) measure incidence and identify associated risk factors and; (3) describe etiologic agents responsible and antibacterial susceptibility patterns. This prospective cohort study builds on the Aetiology of Neonatal Infection in South Asia study in three sites: Sylhet, Bangladesh and Karachi and Matiari, Pakistan. Formative research determined local knowledge of symptoms and signs of postpartum sepsis, and a systematic literature review was conducted to design a diagnostic tool for community health workers to use during ten postpartum home visits. Suspected postpartum sepsis cases were referred to study physicians for independent assessment, which permitted validation of the tool. Clinical specimens, including urine, blood, and endometrial material, were collected for etiologic assessment and antibiotic sensitivity. All women with puerperal sepsis were given appropriate antibiotics. DISCUSSION: This is the first large population-based study to expand community-based surveillance for diagnoses, referral and treatment of newborn sepsis to include maternal postpartum sepsis. Study activities will lead to development and validation of a diagnostic tool for use by community health workers in resource-poor countries. Understanding the epidemiology and microbiology of postpartum sepsis will inform prevention and treatment strategies and improve understanding of linkages between maternal and neonatal infections.


Assuntos
Infecções Assintomáticas , Bacteriemia/diagnóstico , Infecção Puerperal/diagnóstico , Sepse/diagnóstico , Adolescente , Adulto , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções Assintomáticas/epidemiologia , Bacteriemia/tratamento farmacológico , Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Bangladesh/epidemiologia , Estudos de Coortes , Agentes Comunitários de Saúde , Assistência à Saúde Culturalmente Competente/etnologia , Países em Desenvolvimento , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/crescimento & desenvolvimento , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/crescimento & desenvolvimento , Bactérias Gram-Positivas/isolamento & purificação , Visita Domiciliar , Humanos , Incidência , Tipagem Molecular , Paquistão/epidemiologia , Período Pós-Parto , Infecção Puerperal/tratamento farmacológico , Infecção Puerperal/epidemiologia , Infecção Puerperal/microbiologia , Fatores de Risco , Sepse/tratamento farmacológico , Sepse/epidemiologia , Sepse/microbiologia , Adulto Jovem
14.
Acta Crystallogr D Biol Crystallogr ; 71(Pt 7): 1514-27, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26143923

RESUMO

17 independent crystal structures of family I uracil-DNA glycosylase from Mycobacterium tuberculosis (MtUng) and its complexes with uracil and its derivatives, distributed among five distinct crystal forms, have been determined. Thermodynamic parameters of binding in the complexes have been measured using isothermal titration calorimetry. The two-domain protein exhibits open and closed conformations, suggesting that the closure of the domain on DNA binding involves conformational selection. Segmental mobility in the enzyme molecule is confined to a 32-residue stretch which plays a major role in DNA binding. Uracil and its derivatives can bind to the protein in two possible orientations. Only one of them is possible when there is a bulky substituent at the 5' position. The crystal structures of the complexes provide a reasonable rationale for the observed thermodynamic parameters. In addition to providing fresh insights into the structure, plasticity and interactions of the protein molecule, the results of the present investigation provide a platform for structure-based inhibitor design.


Assuntos
Mycobacterium tuberculosis/enzimologia , Uracila-DNA Glicosidase/química , Uracila-DNA Glicosidase/metabolismo , Uracila/metabolismo , Sítios de Ligação , Ácido Cítrico/metabolismo , Cristalografia por Raios X , Humanos , Modelos Moleculares , Mycobacterium tuberculosis/química , Mycobacterium tuberculosis/metabolismo , Ligação Proteica , Conformação Proteica , Estrutura Terciária de Proteína , Uracila/análogos & derivados
15.
Clin Exp Immunol ; 180(2): 207-17, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25516468

RESUMO

Type 1 diabetes results from destruction of insulin-producing beta cells in pancreatic islets and is characterized by islet cell autoimmunity. Autoreactivity against non-beta cell-specific antigens has also been reported, including targeting of the calcium-binding protein S100ß. In preclinical models, reactivity of this type is a key component of the early development of insulitis. To examine the nature of this response in type 1 diabetes, we identified naturally processed and presented peptide epitopes derived from S100ß, determined their affinity for the human leucocyte antigen (HLA)-DRB1*04:01 molecule and studied T cell responses in patients, together with healthy donors. We found that S100ß reactivity, characterized by interferon (IFN)-γ secretion, is a characteristic of type 1 diabetes of varying duration. Our results confirm S100ß as a target of the cellular autoimmune response in type 1 diabetes with the identification of new peptide epitopes targeted during the development of the disease, and support the preclinical findings that autoreactivity against non-beta cell-specific autoantigens may have a role in type 1 diabetes pathogenesis.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Epitopos de Linfócito T/imunologia , Imunidade Celular , Subunidade beta da Proteína Ligante de Cálcio S100/imunologia , Linfócitos T/imunologia , Autoantígenos/imunologia , Sequência de Bases , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/patologia , Epitopos de Linfócito T/genética , Feminino , Cadeias HLA-DRB1/genética , Cadeias HLA-DRB1/imunologia , Humanos , Interferon gama/genética , Interferon gama/imunologia , Masculino , Dados de Sequência Molecular , Subunidade beta da Proteína Ligante de Cálcio S100/genética , Linfócitos T/patologia
16.
Clin Exp Immunol ; 177(3): 571-85, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24773525

RESUMO

The appearance of circulating islet-specific autoantibodies before disease diagnosis is a hallmark of human type 1 diabetes (T1D), and suggests a role for B cells in the pathogenesis of the disease. Alterations in the peripheral B cell compartment have been reported in T1D patients; however, to date, such studies have produced conflicting results and have been limited by sample size. In this study, we have performed a detailed characterization of the B cell compartment in T1D patients (n = 45) and healthy controls (n = 46), and assessed the secretion of the anti-inflammatory cytokine interleukin (IL)-10 in purified B cells from the same donors. Overall, we found no evidence for a profound alteration of the B cell compartment or in the production of IL-10 in peripheral blood of T1D patients. We also investigated age-related changes in peripheral B cell subsets and confirmed the sharp decrease with age of transitional CD19(+) CD27(-) CD24(hi) CD38(hi) B cells, a subset that has recently been ascribed a putative regulatory function. Genetic analysis of the B cell compartment revealed evidence for association of the IL2-IL21 T1D locus with IL-10 production by both memory B cells (P = 6·4 × 10(-4) ) and islet-specific CD4(+) T cells (P = 2·9 × 10(-3) ). In contrast to previous reports, we found no evidence for an alteration of the B cell compartment in healthy individuals homozygous for the non-synonymous PTPN22 Trp(620) T1D risk allele (rs2476601; Arg(620) Trp). The IL2-IL21 association we have identified, if confirmed, suggests a novel role for B cells in T1D pathogenesis through the production of IL-10, and reinforces the importance of IL-10 production by autoreactive CD4(+) T cells.


Assuntos
Subpopulações de Linfócitos B/imunologia , Subpopulações de Linfócitos B/metabolismo , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/imunologia , Adolescente , Adulto , Fatores Etários , Autoanticorpos/imunologia , Estudos de Casos e Controles , Criança , Citocinas/biossíntese , Diabetes Mellitus Tipo 1/metabolismo , Feminino , Citometria de Fluxo , Regulação da Expressão Gênica , Estudos de Associação Genética , Humanos , Imunofenotipagem , Masculino , Fenótipo , Proteína Tirosina Fosfatase não Receptora Tipo 22/genética , Transdução de Sinais , Adulto Jovem
17.
Sci Data ; 11(1): 496, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38750041

RESUMO

Meningiomas are the most common primary intracranial tumors and can be associated with significant morbidity and mortality. Radiologists, neurosurgeons, neuro-oncologists, and radiation oncologists rely on brain MRI for diagnosis, treatment planning, and longitudinal treatment monitoring. However, automated, objective, and quantitative tools for non-invasive assessment of meningiomas on multi-sequence MR images are not available. Here we present the BraTS Pre-operative Meningioma Dataset, as the largest multi-institutional expert annotated multilabel meningioma multi-sequence MR image dataset to date. This dataset includes 1,141 multi-sequence MR images from six sites, each with four structural MRI sequences (T2-, T2/FLAIR-, pre-contrast T1-, and post-contrast T1-weighted) accompanied by expert manually refined segmentations of three distinct meningioma sub-compartments: enhancing tumor, non-enhancing tumor, and surrounding non-enhancing T2/FLAIR hyperintensity. Basic demographic data are provided including age at time of initial imaging, sex, and CNS WHO grade. The goal of releasing this dataset is to facilitate the development of automated computational methods for meningioma segmentation and expedite their incorporation into clinical practice, ultimately targeting improvement in the care of meningioma patients.


Assuntos
Imageamento por Ressonância Magnética , Neoplasias Meníngeas , Meningioma , Meningioma/diagnóstico por imagem , Humanos , Neoplasias Meníngeas/diagnóstico por imagem , Masculino , Feminino , Processamento de Imagem Assistida por Computador/métodos , Pessoa de Meia-Idade , Idoso
18.
Cutis ; 91(4): 198-202, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23763081

RESUMO

Verruciform xanthoma (VX) is an uncommon mucocutaneous lesion of uncertain etiology. Originally thought to be limited to the oral mucosa, its occurrence in other mucosal and nonmucosal sites also has been documented. Histologically, VX is characterized by subepithelial foamy histiocytes associated with papillomatosis, parakeratosis, and dyskeratosis. Subepithelial foamy cells are lipid-containing, non-Langerhans cell histiocytes. A variety of etiologies have been proposed without much consensus, including infectious (bacterial, viral, and fungal), degenerative, reactive/ reparative, inflammatory, metabolic, reactive/ multifactorial, and immunosuppressive factors. Verruciform xanthoma of the external ear is exceedingly rare. Herein, we report a rare case of VX occurring on the earlobe at a piercing site in an immunosuppressed patient and provide a discussion of the possible pathogenetic mechanism(s).


Assuntos
Hospedeiro Imunocomprometido , Dermatopatias/patologia , Xantomatose/patologia , Idoso , Piercing Corporal , Orelha Externa , Feminino , Histiócitos/metabolismo , Humanos
19.
Bangladesh Med Res Counc Bull ; 39(3): 109-15, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26118157

RESUMO

National Malaria Control Program (NMCP) of Bangladesh has introduced Artemisinin Based Combination (ACT), Coartem(R) (Artemether-Lumefantrine (AL), fixed dose combination, in the confirmed cases of uncomplicated P. falciparum malaria since 2004. Despite the reduction of mortality due to malaria, the development and spread of anti-malarial drug resistance wordwide posing a threat to the health services and will make it difficult to control malaria in Bangladesh in future. We need to have an alternative to Coartem which could be Artesunate-amodiaquine (AA) in a fixed dose combination (FDC), a cheaper altenative not yet evidenced to be effective and safe to our population. In this study we compared the efficacy and safety of Artemether + Lumefantrene (FDC, Coartem) with Artesunate +Amodiaquine tablets (100/270 mg FDC) for the treatment of uncomplicated P. falciparum malaria in three high risk multi-drug resistant malaria prevalent areas of Bangladesh. It was an open label randomized controlled trial conducted between December 2008 and November 2009 in 4 upazillas in patients over the age 12 to 60 years diagnosed as a case of uncomplicated P. falciparum malaria. The outcome of the cases were measured as clinical response, parasitological response, defervescence time and parasite clearance time. Drug safety was assessed by comparing the adverse events. A total of 252 cases were randomized to receive Artesunate + Amodiaquine (AA group, 147 cases) and Artemether + Lumefantrene (AL group, 106 cases), one lost to follow up at day 28 in AA group. The distribution of the cases was comparable by age, sex and study sites. Treatment success' response was observed 100% in the AL group and AA group had 99%, two failures with AA were late treatment failures and the difference was not statistically significant (p > .1). The parasitological sensitive (S) response was observed in 97% of cases in AL group and 95% in the AA group, and was not a statistically significant difference. There was no significant difference in deffervescence time and parasite clearance time between two groups of cases. No serious adverse events were observed. The frequencies of minor adverse events were insignificantly different between the two treatment groups. The two ACT regimen, AA and AL had no significant difference in efficacy and safety for treatment of Uncomplicated Malaria in Bangladesh. However, there were few more failures with AA regimen compared to AL regimen, which was not statistically significant. Both these regimens can be used alternatively by the NMCP of Bangladesh as first-line treatment option.


Assuntos
Amodiaquina/uso terapêutico , Antimaláricos/uso terapêutico , Artemisininas/uso terapêutico , Etanolaminas/uso terapêutico , Fluorenos/uso terapêutico , Malária Falciparum/tratamento farmacológico , Adolescente , Adulto , Combinação Arteméter e Lumefantrina , Bangladesh , Criança , Pré-Escolar , Combinação de Medicamentos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem
20.
J Clin Med Res ; 15(1): 31-37, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36755764

RESUMO

Background: Mucormycosis necessitates rapid diagnosis and treatment. Microscopy and culture have been considered the gold standard for diagnosis but both take time of 3 - 5 days. KOH mount is another method for fungal identification that takes 1 - 2 h, but it has its own limitations. This study evaluated crush smear as a means of rapid cytological diagnosis. Methods: Biopsy tissue (pre-treatment) from clinically suspicious mucormycosis patients (n = 52) was received in normal saline and crush/imprint smears were prepared; the remaining tissue was processed as routine biopsy specimen. After the rapid initial cytological identification, the patients were managed according to the standard clinical protocol. Random post-therapeutic biopsy samples of some of these patients (n = 19) were also obtained and again evaluated cytologically. Results: Crush smears showed sensitivity/specificity of 77.7%/75.0% with histopathology and 72.2%/62.5% with culture, respectively, while KOH mount had values of 71.4%/70.5% with histopathology and 79.3%/69.5% with culture, respectively. Degenerative fungal morphological characteristics and cellular inflammatory infiltrate (predominantly neutrophilic) in the vicinity of fungal hyphae were compared in pre- and post-treatment groups, and we found a statistically significant difference (P < 0.05) between them. Conclusion: Our preliminary results suggest that crush smear cytology is a simple, rapid, cost-effective and easily available method for diagnosing mucormycosis. Moreover, crush smears also demonstrated morphological alteration in hyphal structure and accompanying immune cell infiltration which may provide valuable insights into mechanism of therapy/host immune response against fungal pathogen.

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