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1.
Mymensingh Med J ; 33(3): 772-776, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38944720

RESUMO

Soft tissue injuries of the hand or forearm often results in exposure of tendon or bone which needs coverage with a suitable flap. This prospective observational study was carried out in National Institute of Traumatology and Orthopaedic Rehabilitation (NITOR), Dhaka, Bangladesh from February 2019 to January 2020, to evaluate the use of the pedicled paraumbilical perforator flaps as a reliable flap to cover such defects. Total 34 patients having soft tissue defects in the hand and forearm with exposed tendons, bones or implant were included in this study. All the defects were covered by paraumbilical perforator flap. The defects were caused by road traffic accident (n=22), machinery injury (n=10) and burn injury (n=2). Sixteen patients had defects involving the forearm, six over dorsum of hand, another two over first web space and the rest had defects over two or more areas of forearm, hand and wrist. Lateral extent of flaps was upto anterior axillary line in 41.18% cases and upto mid-axillary line in 55.88% cases. Flap division and final inset was done in second stage after 3 weeks. Donor site closed primarily in all cases, except in two cases where it was covered by skin graft. All the flaps survived with no incidence of flap necrosis, dehiscence or infection after first stage. However, after the division of the flap, two patients developed marginal necrosis of the proximal margin which healed spontaneously by conservative treatment. The mean flap surface area utilized was 108 cm2. Donor area healed well without any major complications. Three patients developing scar hypertrophy were treated with intra-lesional triamcinolone injections. The paraumbilical perforator flap is a reliable option to cover soft tissue defects of hand and forearm due to easier planning and harvesting of the flap, adequate skin paddle and minimum donor site morbidity.


Assuntos
Traumatismos da Mão , Retalho Perfurante , Lesões dos Tecidos Moles , Humanos , Retalho Perfurante/transplante , Masculino , Lesões dos Tecidos Moles/cirurgia , Feminino , Adulto , Estudos Prospectivos , Traumatismos da Mão/cirurgia , Pessoa de Meia-Idade , Antebraço/cirurgia , Adolescente , Traumatismos do Antebraço/cirurgia , Adulto Jovem , Procedimentos de Cirurgia Plástica/métodos , Criança
2.
J Digit Imaging ; 36(5): 2227-2248, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37407845

RESUMO

Cancerous skin lesions are one of the deadliest diseases that have the ability in spreading across other body parts and organs. Conventionally, visual inspection and biopsy methods are widely used to detect skin cancers. However, these methods have some drawbacks, and the prediction is not highly accurate. This is where a dependable automatic recognition system for skin cancers comes into play. With the extensive usage of deep learning in various aspects of medical health, a novel computer-aided dermatologist tool has been suggested for the accurate identification and classification of skin lesions by deploying a novel deep convolutional neural network (DCNN) model that incorporates global average pooling along with preprocessing to discern the skin lesions. The proposed model is trained and tested on the HAM10000 dataset, which contains seven different classes of skin lesions as target classes. The black hat filtering technique has been applied to remove artifacts in the preprocessing stage along with the resampling techniques to balance the data. The performance of the proposed model is evaluated by comparing it with some of the transfer learning models such as ResNet50, VGG-16, MobileNetV2, and DenseNet121. The proposed model provides an accuracy of 97.20%, which is the highest among the previous state-of-art models for multi-class skin lesion classification. The efficacy of the proposed model is also validated by visualizing the results obtained using a graphical user interface (GUI).


Assuntos
Aprendizado Profundo , Dermatopatias , Neoplasias Cutâneas , Humanos , Dermatopatias/diagnóstico por imagem , Pele/diagnóstico por imagem , Pele/patologia , Neoplasias Cutâneas/diagnóstico por imagem , Neoplasias Cutâneas/patologia , Redes Neurais de Computação
3.
Trends Biotechnol ; 41(10): 1248-1267, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37147246

RESUMO

Prostate cancer (PC) is one of the most common tumors and a leading cause of mortality among men, resulting in ~375 000 deaths annually worldwide. Various analytical methods have been designed for quantitative and rapid detection of PC biomarkers. Electrochemical (EC), optical, and magnetic biosensors have been developed to detect tumor biomarkers in clinical and point-of-care (POC) settings. Although POC biosensors have shown potential for detection of PC biomarkers, some limitations, such as the sample preparation, should be considered. To tackle such shortcomings, new technologies have been utilized for development of more practical biosensors. Here, biosensing platforms for the detection of PC biomarkers such as immunosensors, aptasensors, genosensors, paper-based devices, microfluidic systems, and multiplex high-throughput platforms, are discussed.


Assuntos
Técnicas Biossensoriais , Neoplasias da Próstata , Humanos , Masculino , Técnicas Biossensoriais/métodos , Imunoensaio , Sistemas Automatizados de Assistência Junto ao Leito , Neoplasias da Próstata/diagnóstico , Biomarcadores Tumorais , Técnicas Eletroquímicas
4.
Braz. j. biol ; 83: e246803, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339417

RESUMO

Abstract Traditional medicine is cheaper and easily available to local people, to care for most frequent diseases in the Northern parts of Pakistan. Our study aimed at inventorying medicine from local plants, documenting their uses, and assessing their market value in 2015-2018 during spring, summer, and winter seasons. A total of 15 trips were made, 5 in each season. Semi-structured interviews with 165 inhabitant's age range between 20-80 years were conducted, analyzed the data is analyzed using Relative frequency of citation(RFC), Use Value(UV), Fidelity Level(FL), Informants consensus factor(ICF), and Jaccard index(JI) to find the most frequent and well-known used species in the area. A total of 86 species belonging to 39 vascular plant families, 33 genera were documented as medicinally important. Family Asteraceae was observed as the dominant family among all the families with 10 species, the leaf was the most used parts and decoction 36% was the most preferred preparation type. Herb was the predominant life form (67%). The maximum UV (0.92) was demonstrated by J. adhatoda L. species, while A. sativum L. shows maximum RFC (0.58), the highest ICF value represented by diarrhea and dermatitis 0.92, and high FL value is recorded 100%. According to our collections, wild species were 45%, invasive species were 38% and cultivated 17% recorded, dicots species were recorded more 81%. Seven 7 medicinal species is being economically important and export to the local and international market of the world, whereas P. integrima L. species were the most exported species according to the local dealers. The investigated area is rural and the local people depend on the area's plants for their health needs, and other uses like a vegetable, fuelwood, fodder, etc. The current result of RFC, UV, ICF, FL, and JI shows that medicinal flora needs to be pharmacologically and phytochemically investigated to prove their efficacy. The documentation of medicinal knowledge is important to preserve this precious old knowledge before it is lost forever, due to technological and environmental changes in the world.


Resumo A medicina tradicional é mais barata e facilmente disponível à população local para cuidar das doenças mais frequentes nas áreas do norte do Paquistão. Nosso estudo teve como objetivo inventariar medicamentos de plantas locais, documentar seus usos e avaliar seu valor de mercado em 2015-2018 durante as temporadas de primavera, verão e inverno. Foram feitas 15 viagens, 5 em cada temporada. Foram realizadas entrevistas semiestruturadas com 165 moradores na faixa etária de 20 a 80 anos, com dados analisados ​​por meio de frequência relativa de citação (RFC), valor de uso (UV), nível de fidelidade (FL), fator de consenso de informantes (CIF), e o índice de Jaccard (JI) para encontrar as espécies utilizadas mais frequentes e conhecidas na área. Um total de 86 espécies pertencentes a 39 famílias de plantas vasculares, 33 gêneros foram documentados como medicamente importantes. A família Asteraceae foi observada como a família dominante entre todas as famílias com 10 espécies, a folha foi a parte mais utilizada e a decocção 36% foi o tipo de preparação mais preferido. A erva foi a forma de vida predominante (67%). O UV máximo (0,92) foi demonstrado pelas espécies de J. adhatoda L., enquanto A. sativum L. mostra RFC máximo (0,58), o maior valor de ICF representado por diarreia e dermatite 0,92, e alto valor de FL é registrado 100%. De acordo com nossas coleções, as espécies selvagens foram 45%, as espécies invasoras 38% e as cultivadas 17% registradas, as espécies dicotiledôneas foram registradas mais 81%. Sete espécies medicinais estão sendo economicamente importantes e exportadas para o mercado local e internacional do mundo, enquanto as espécies de P. integrima L. foram as espécies mais exportadas de acordo com os comerciantes locais. A área investigada é rural e a população local depende das plantas da área para suas necessidades de saúde e outros usos como vegetal, lenha, forragem etc. O resultado atual de RFC, UV, ICF, FL e JI mostra que a flora medicinal precisa ser investigada farmacológica e fitoquimicamente para comprovar sua eficácia. A documentação do conhecimento medicinal é importante para preservar esse precioso conhecimento antigo antes que se perca para sempre, devido às mudanças tecnológicas e ambientais do mundo.


Assuntos
Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Adulto Jovem , Plantas Medicinais , Paquistão , Inquéritos e Questionários , Folhas de Planta , Etnobotânica , Fitoterapia , Medicina Tradicional
5.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469135

RESUMO

Abstract Traditional medicine is cheaper and easily available to local people, to care for most frequent diseases in the Northern parts of Pakistan. Our study aimed at inventorying medicine from local plants, documenting their uses, and assessing their market value in 2015-2018 during spring, summer, and winter seasons. A total of 15 trips were made, 5 in each season. Semi-structured interviews with 165 inhabitants age range between 20-80 years were conducted, analyzed the data is analyzed using Relative frequency of citation(RFC), Use Value(UV), Fidelity Level(FL), Informants consensus factor(ICF), and Jaccard index(JI) to find the most frequent and well-known used species in the area. A total of 86 species belonging to 39 vascular plant families, 33 genera were documented as medicinally important. Family Asteraceae was observed as the dominant family among all the families with 10 species, the leaf was the most used parts and decoction 36% was the most preferred preparation type. Herb was the predominant life form (67%). The maximum UV (0.92) was demonstrated by J. adhatoda L. species, while A. sativum L. shows maximum RFC (0.58), the highest ICF value represented by diarrhea and dermatitis 0.92, and high FL value is recorded 100%. According to our collections, wild species were 45%, invasive species were 38% and cultivated 17% recorded, dicots species were recorded more 81%. Seven 7 medicinal species is being economically important and export to the local and international market of the world, whereas P. integrima L. species were the most exported species according to the local dealers. The investigated area is rural and the local people depend on the area's plants for their health needs, and other uses like a vegetable, fuelwood, fodder, etc. The current result of RFC, UV, ICF, FL, and JI shows that medicinal flora needs to be pharmacologically and phytochemically investigated to prove their efficacy. The documentation of medicinal knowledge is important to preserve this precious old knowledge before it is lost forever, due to technological and environmental changes in the world.


Resumo A medicina tradicional é mais barata e facilmente disponível à população local para cuidar das doenças mais frequentes nas áreas do norte do Paquistão. Nosso estudo teve como objetivo inventariar medicamentos de plantas locais, documentar seus usos e avaliar seu valor de mercado em 2015-2018 durante as temporadas de primavera, verão e inverno. Foram feitas 15 viagens, 5 em cada temporada. Foram realizadas entrevistas semiestruturadas com 165 moradores na faixa etária de 20 a 80 anos, com dados analisados por meio de frequência relativa de citação (RFC), valor de uso (UV), nível de fidelidade (FL), fator de consenso de informantes (CIF), e o índice de Jaccard (JI) para encontrar as espécies utilizadas mais frequentes e conhecidas na área. Um total de 86 espécies pertencentes a 39 famílias de plantas vasculares, 33 gêneros foram documentados como medicamente importantes. A família Asteraceae foi observada como a família dominante entre todas as famílias com 10 espécies, a folha foi a parte mais utilizada e a decocção 36% foi o tipo de preparação mais preferido. A erva foi a forma de vida predominante (67%). O UV máximo (0,92) foi demonstrado pelas espécies de J. adhatoda L., enquanto A. sativum L. mostra RFC máximo (0,58), o maior valor de ICF representado por diarreia e dermatite 0,92, e alto valor de FL é registrado 100%. De acordo com nossas coleções, as espécies selvagens foram 45%, as espécies invasoras 38% e as cultivadas 17% registradas, as espécies dicotiledôneas foram registradas mais 81%. Sete espécies medicinais estão sendo economicamente importantes e exportadas para o mercado local e internacional do mundo, enquanto as espécies de P. integrima L. foram as espécies mais exportadas de acordo com os comerciantes locais. A área investigada é rural e a população local depende das plantas da área para suas necessidades de saúde e outros usos como vegetal, lenha, forragem etc. O resultado atual de RFC, UV, ICF, FL e JI mostra que a flora medicinal precisa ser investigada farmacológica e fitoquimicamente para comprovar sua eficácia. A documentação do conhecimento medicinal é importante para preservar esse precioso conhecimento antigo antes que se perca para sempre, devido às mudanças tecnológicas e ambientais do mundo.

6.
Mymensingh Med J ; 30(4): 1100-1106, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34605483

RESUMO

Cancer of the uterine cervix is one of the leading causes of mortality and morbidity among women in poor countries. It is the most common reproductive cancer among women in Bangladesh and most women are diagnosed at advanced stage when appropriate treatment is not possible. But this cancer is preventable through proper screening and simultaneous treatment of premalignant lesions. The same day "Screen and Treat" approach is an endeavour to reach the goal especially at low resource settings. Ablation of precancerous lesions by thermo-coagulation is a promising mode of complete cure as this method is easy to apply, effective and relatively cheaper than other procedures. To avoid the issue of overtreatment, an intermediate approach- colposcopy can be used. Aim of this study was to diagnose premalignant lesions of cervix during screening procedure and to treat the lesions by thermo-coagulation at the same sitting. This prospective study was carried out at Upzilla Health Complex (UHC), Rangunia, from 3rd February 2018 to 6th February 2018 in a campaign of cervical cancer screening program by visual inspection of cervix with 5.00% acetic acid (VIA). About 1000 women attending the outpatient department were enrolled in this study by consecutive sampling technique according to inclusion and exclusion criteria. Informed consent was taken after explaining the screening method, thermo-coagulation procedure and follow up schedule. VIA was found positive in 22 cases. Colposcopy was done in VIA positive cases by Gynocular colposcope. Punch biopsy was taken when colposcopy revealed positive in 12 women. Then thermo-coagulation was done. Histopathology report revealed, CIN1 (cervical intraepithelial neoplasia 1)- in 6 cases (50.00%); CIN 2 (cervical intraepithelial neoplasia 2)- in 01 case (8.33%); Chronic cervicitis with squamous metaplasia- in 05 cases (41.67%). Sensitivity and specificity of colposcopy was calculated considering colposcopy directed biopsy as gold standard, which was 100.00% and 75.00% respectively in CIN-1. While in CIN-2 it was 100.00% and 95.20% respectively. VIA is an effective screening tool for cancer cervix. Main advantage is the "screen and treat" approach can be attempted for at risk women in low resource setting by thermo-coagulation which is accepted by women while guaranteeing satisfactory cure rates. Thus, reduces loss to follow-up and have an impact on cervical cancer control.


Assuntos
Displasia do Colo do Útero , Neoplasias do Colo do Útero , Ácido Acético , Colposcopia , Detecção Precoce de Câncer , Feminino , Humanos , Programas de Rastreamento , Gravidez , Estudos Prospectivos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/cirurgia , Displasia do Colo do Útero/diagnóstico , Displasia do Colo do Útero/cirurgia
7.
Mymensingh Med J ; 30(3): 846-849, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34226478

RESUMO

Polyorchidism is a rare congenital anomaly reported about 200 cases in the world text. A number of theories have been planned concerning the making of polyorchidism, but the real explanation is still not acknowledged. Here we are going to present a case study of polyorchidism. A 70 years old gentleman complained with left supernumerary testes in the left hemiscrotum. His left hemiscrotum was painless with mass. Polyorchidism without malignancy or any other concomitant features were revealed by both ultrasound and MRI examinations. In most cases the ultrasonograph alone is diagnostic. In complicated cases of polyorchidism MRI may provide additional information.


Assuntos
Imageamento por Ressonância Magnética , Testículo , Idoso , Humanos , Masculino , Escroto/diagnóstico por imagem , Testículo/diagnóstico por imagem , Ultrassonografia
8.
Carbohydr Polym ; 236: 116101, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32172900

RESUMO

Functionalised nanohybrid hydrogel using L-Histidine (HIS) conjugated chitosan, phyto-synthesised zinc oxide nanoparticles (ZNPs) and dialdehyde cellulose (DAC) was formulated as a sustained drug delivery carrier for the polyphenol drugs - Naringenin (NRG), Quercetin (QE) and Curcumin (CUR). A maximum loading efficiency of 90.55 %, 92.84 % and 89.89 %, respectively were optimised for NRG, QE and CUR in the hybrid hydrogel. The maximum drug release was favoured for the optimum drug loading and at pH-5. HIS-chitosan conjugation stabilised the hydrogel and enabled a sustained drug delivery. Drug release kinetics predicted a non-Fickian diffusion-based mechanism along with polymer erosion. Prominent antimicrobial activity against Staphylococcus aureus and Trichophyton rubrum strains were predicted to evolve based on the synergic formulation. Significant biocompatibility towards L929 cells revealed their support for normal cell survival. Anticancer studies towards A431 cells exhibited excellent cytotoxicity with a 15 to 30-fold increase using the hybrid carrier, compared to the free polyphenol drugs.


Assuntos
Celulose/química , Quitosana/química , Portadores de Fármacos/química , Histidina/química , Hidrogéis/química , Nanopartículas Metálicas/química , Animais , Antibacterianos/química , Antibacterianos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Curcumina/química , Curcumina/farmacologia , Liberação Controlada de Fármacos , Flavanonas/química , Flavanonas/farmacologia , Humanos , Hidrogéis/síntese química , Cinética , Camundongos , Quercetina/química , Quercetina/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Trichophyton/efeitos dos fármacos , Óxido de Zinco/química
9.
Int J Biol Macromol ; 132: 784-794, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30951778

RESUMO

The therapeutic prospective of a novel carrier based delivery of phyto-derived quercetin (QE) extracted from onion peel waste was studied in the present work. Dialdehyde cellulose (DAC) developed from sugarcane bagasse (SCB) cellulose effectively crosslinked chitosan hydrogel. The hydrogel matrices were embedded with green zinc oxide nanoparticles (ZnO NPs), phyto-synthesized using musk melon seeds. The hybrid carrier formulation was characterised using analytical techniques such as XRD, FTIR and SEM analysis. The onion peel drug (OPD) analysed for its bioactive components using HPLC was reported as a potential source of QE. Taguchi optimization for the QE drug loading in the nanohybrid hydrogel indicated a remarkable improvement by 39% in comparison to drug loading in hydrogel without ZnO NPs. The maximum QE release was obtained at an optimal drug loading condition with pH 5.0, which favoured the anticancer applications. The drug release revealed a Fickian diffusion mechanism by adopting various kinetic models. The commercial QE and QE in OPD (QE/OPD) loaded nanohybrid hydrogels were found to inhibit the growth of Staphylococcus aureus and Trichophyton rubrum strains. The biocompatibility and anticancer properties of the QE/OPD loaded nanohybrid hydrogels were established against normal L929 murine fibroblast cells and A431 human skin carcinoma cell lines respectively.


Assuntos
Celulose/química , Quitosana/química , Hidrogéis/química , Nanopartículas/química , Cebolas/química , Quercetina/química , Óxido de Zinco/química , Animais , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Preparações de Ação Retardada , Portadores de Fármacos/química , Portadores de Fármacos/farmacologia , Humanos , Cinética , Camundongos , Propriedades de Superfície
10.
Mymensingh Med J ; 27(1): 6-12, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29459585

RESUMO

Ultrasonography is a very useful diagnostic tool to evaluate pediatric abdominal mass. This cross sectional study was conducted among clinically suspected patients having malignant abdominal mass attending in the department of Radiology & Imaging, Mymensingh Medical College Hospital, Mymensingh, Bangladesh from January 2008 to December 2009. Total 56 patients were included in this study. Patients were scanned by high resolution gray scale ultrasonography of the abdominal masses. After surgical procedure, biopsy specimen were collected in a container containing 10% formalin and sent for histopathological examination. Mean age of the patients group was 5.91 years with a standard deviation of ±3.21 years. All patients were within 2 to 13 years age. Out of all patients, male were 33(58.9%) and 23(41.1%) were female. Male and female ratio was 1.4:1. Ultrasonographic diagnosis as Wilm's tumour were 27(48.2%), hepatoblastoma 8(14.3%), lymphoma 7(12.5%), neuroblastoma 6(10.7%), suspected malignancy 6(10.7%) and lastly teratoma were 2(3.6%). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of ultrasonography in the evaluation of Wilm's tumour were 100.0%, 90.6%, 88.9%, 100.0% and 94.6% for neuroblastoma 83.3%, 98.0%, 83.3%, 98.0% and 96.4% for lymphoma 83.3%, 96.0%, 71.4%, 98.0% and 94.6% and for hepatoblastoma 100.0%, 100.0%, 100.0%, 100.0% and 100.0% respectively. It is a noninvasive and cost effective modality. Carefully performed ultrasonographic study would give reliable and accurate information needed in the diagnosis of abdominal malignancy in children.


Assuntos
Neoplasias Abdominais , Neoplasias Abdominais/diagnóstico , Neoplasias Abdominais/patologia , Bangladesh , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Sensibilidade e Especificidade
11.
Mymensingh Med J ; 26(1): 205-207, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-28260778

RESUMO

We came across a 32 years old male admitted in our hospital with prolonged low-grade fever, haemoptysis, leg swelling, weight loss, purpuric rashes and malaena. He received anti-TB treatment at another hospital without any improvement. He was pale with bullous and purpuric lesions over legs and feet. He also had features of consolidation over both lung fields. His CRP was 312mg/L, Urine R/M/E showed 40-50 RBC/HPF, Chest X-ray showed features of bilateral consolidation, c-ANCA-10U/L (positive); Tracheal aspirate for AFB was found to be negative. We diagnosed the case as Granulomatosis with Polyangitis (WG) and started treatment with steroid and cyclophosphamide. But the patient could not be saved probably due to delay in starting management.


Assuntos
Granulomatose com Poliangiite , Adulto , Anticorpos Anticitoplasma de Neutrófilos , Ciclofosfamida/uso terapêutico , Granulomatose com Poliangiite/diagnóstico , Granulomatose com Poliangiite/tratamento farmacológico , Humanos , Imunossupressores/uso terapêutico , Pulmão , Masculino , Radiografia
12.
J Biol Chem ; 276(35): 33196-212, 2001 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-11337487

RESUMO

Expression in dendritic cells (DCs) of DC-SIGN, a type II membrane protein with a C-type lectin ectodomain, is thought to play an important role in establishing the initial contact between DCs and resting T cells. DC-SIGN is also a unique type of human immunodeficiency virus-1 (HIV-1) attachment factor and promotes efficient infection in trans of cells that express CD4 and chemokine receptors. We have identified another gene, designated here as DC-SIGN2, that exhibits high sequence homology with DC-SIGN. Here we demonstrate that alternative splicing of DC-SIGN1 (original version) and DC-SIGN2 pre-mRNA generates a large repertoire of DC-SIGN-like transcripts that are predicted to encode membrane-associated and soluble isoforms. The range of DC-SIGN1 mRNA expression was significantly broader than previously reported and included THP-1 monocytic cells, placenta, and peripheral blood mononuclear cells (PBMCs), and there was cell maturation/activation-induced differences in mRNA expression levels. Immunostaining of term placenta with a DC-SIGN1-specific antiserum showed that DC-SIGN1 is expressed on endothelial cells and CC chemokine receptor 5 (CCR5)-positive macrophage-like cells in the villi. DC-SIGN2 mRNA expression was high in the placenta and not detectable in PBMCs. In DCs, the expression of DC-SIGN2 transcripts was significantly lower than that of DC-SIGN1. Notably, there was significant inter-individual heterogeneity in the repertoire of DC-SIGN1 and DC-SIGN2 transcripts expressed. The genes for DC-SIGN1, DC-SIGN2, and CD23, another Type II lectin, colocalize to an approximately 85 kilobase pair region on chromosome 19p13.3, forming a cluster of related genes that undergo highly complex alternative splicing events. The molecular diversity of DC-SIGN-1 and -2 is reminiscent of that observed for certain other adhesive cell surface proteins involved in cell-cell connectivity. The generation of this large collection of polymorphic cell surface and soluble variants that exhibit inter-individual variation in expression levels has important implications for the pathogenesis of HIV-1 infection, as well as for the molecular code required to establish complex interactions between antigen-presenting cells and T cells, i.e. the immunological synapse.


Assuntos
Antígenos de Diferenciação , Moléculas de Adesão Celular/metabolismo , Células Dendríticas/imunologia , Células-Tronco Hematopoéticas/imunologia , Lectinas Tipo C , Lectinas/genética , Lectinas/imunologia , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/imunologia , Adulto , Sequência de Aminoácidos , Antígenos CD/sangue , Antígenos CD34/sangue , Sequência de Bases , Sítios de Ligação , Diferenciação Celular , Linhagem Celular , Células Dendríticas/citologia , Endotélio Vascular/citologia , Endotélio Vascular/imunologia , Éxons , Feminino , Variação Genética , Células-Tronco Hematopoéticas/citologia , Humanos , Lectinas/química , Macrófagos/citologia , Macrófagos/imunologia , Dados de Sequência Molecular , Placenta/citologia , Placenta/imunologia , Gravidez , Biossíntese de Proteínas , Isoformas de Proteínas/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/imunologia , RNA Mensageiro/genética , Receptores de Superfície Celular/química , Proteínas Recombinantes/química , Proteínas Recombinantes/imunologia , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Transcrição Gênica , Transfecção
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