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1.
Osteoarthr Cartil Open ; 6(2): 100440, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38385105

RESUMO

Objective: Knee osteoarthritis (OA) is a complex disease with heterogeneous representations. Although it is modifiable to prevention and early treatment, there still lacks a reliable and accurate prognostic tool. Hence, we aim to develop a quantitative and self-administrable knee replacement (KR) risk stratification system for knee osteoarthritis (KOA) patients with clinical features. Method: A total of 14 baseline features were extracted from 9592 cases in the Osteoarthritis Initiative (OAI) cohort. A survival model was constructed using the Random Survival Forests algorithm. The prediction performance was evaluated with the concordance index (C-index) and average receiver operating characteristic curve (AUC). A three-class KR risk stratification system was built to differentiate three distinct KR-free survival groups. Thereafter, Shapley Additive Explanations (SHAP) was introduced for model explanation. Results: KR incidence was accurately predicted by the model with a C-index of 0.770 (±0.0215) and an average AUC of 0.807 (±0.0181) with 14 clinical features. Three distinct survival groups were observed from the ten-point KR risk stratification system with a four-year KR rate of 0.79%, 5.78%, and 16.2% from the low, medium, and high-risk groups respectively. KR is mainly caused by pain medication use, age, surgery history, diabetes, and a high body mass index, as revealed by SHAP. Conclusion: A self-administrable and interpretable KR survival model was developed, underscoring a KR risk scoring system to stratify KOA patients. It will encourage regular self-assessments within the community and facilitate personalised healthcare for both primary and secondary prevention of KOA.

2.
Osteoarthr Cartil Open ; 3(1): 100135, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36475069

RESUMO

Objectives: By deploying a novel combination of machine learning approaches, we aim to investigate the contributions of each local and systemic risk factors in multi-etiology of knee osteoarthritis (KOA) to disease onset and deterioration. Methods: A machine-learning-based KOA progression prediction model is developed using the data from the National Institute of Health Osteoarthritis Biomarkers Consortium. According to Kellgren-Lawrence (KL) grade of plain radiographs at baseline, the subjects are divided into either KOA onset or deterioration study groups. The disease progression is defined as the changes in both joint space width (JSW) and WOMAC pain score. In addition to radiographic and symptomatic data, the anthropological particulars, history of the knee injury and surgery, metabolic syndrome and living habits were deployed in a multi-layer perceptron (MLP) to predict disease progression in each study group. The relative contributions of each risk factors were weighted via DeepLIFT gradient. Additionally, statistical interactions among risk factors were identified compared. Results: Our model achieved AUC of 0.843 (95% CI 0.824, 0.862) and 0.765 (95% CI 0.756, 0.774) in prediction of KOA onset and deterioration, respectively. For KOA onset prediction, history of injury has attained the highest DeepLIFT gradient except medial joint space narrowing; while for KOA deterioration prediction, diabetes and habit of smoking obtained second and third highest gradients respectively aside from medial joint space narrowing, surpassing the impact of the injury. Conclusion: We developed a machine learning workflow which effectively dissects the risk factors' contributions and their mutual interactions for onset and deterioration of KOA respectively.

3.
Med J Malaysia ; 75(1): 18-23, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32008014

RESUMO

INTRODUCTION: People often judge others and make decisions based on the physical appearance of an individual. This study assesses the perception and psychosocial judgment on patients with acne vulgaris compared to those with clear skin. METHODS: This survey was conducted in Penang from October 2016 to June 2017. Respondents were those who were ≥18 years. The survey was conducted using a questionnaire which consists of three randomly selected facial pictures, with at least one acne skin and one clear skin picture. RESULTS: A total of 435 respondents were recruited. Two third of the respondents (76%) suffered or had suffered from acne. The skin was the first thing noticed by 76.1% respondents when viewing pictures with acne compared with 24.8% with clear skin (p <0.05). People with acne were perceived as being unattractive, sad, lonely, distant, unhealthy, disheveled and shy as compared to people with clear skin (p<0.05). People with clear skin were perceived to be healthier, confident, happy, attractive, successful and intelligent (p<0.05). Respondents were more willing to engage socially with people with clear skin rather than those with acne skin. A significantly higher proportion of respondents were likely to hire or vote for those with clear skin as compared to acne skin. People with acne were also perceived to have a lower educational level and poorer leadership quality. CONCLUSION: The results of this survey showed that there were significantly negative perception and psychological judgement toward individuals with acne vulgaris. These negative impacts may affect social life of the acne sufferers, their prospect of employment and career opportunities.


Assuntos
Acne Vulgar/psicologia , Julgamento , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Adulto Jovem
4.
Med J Malaysia ; 73(2): 73-77, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29703869

RESUMO

INTRODUCTION: Severe cutaneous adverse drug reactions (SCARs) are not uncommon and potentially lifethreatening. Our objective is to study the patient characteristics, the pattern of implicated drugs and treatment outcome among patients with SCARs. METHODS: A 10-year retrospective analysis of SCARs cases in Penang General Hospital was carried out from January 2006 to December 2015. Data collection is based on the Malaysian Adverse Drug Reactions Advisory Committee registry and dermatology clinic records. RESULTS: A total of 189 cases of SCARs were encountered (F:M ratio; 1.2:1.0; mean age of 45 year). The commonest manifestation was Stevens-Johnson Syndrome [SJS] (55.0%), followed by toxic epidermal necrolysis [TEN] (23.8%), drug rash with eosinophilia and systemic symptoms [DRESS] (12.7%), acute generalised exanthematous pustulosis [AGEP] (4.8%), SJS/TEN overlap syndrome (2.6%) and generalised bullous fixed drug eruptions [GBFDE] (1.1%). Mean time to onset for TEN/SJS/Overlap syndrome was 10.5±13 days; AGEP, three days; GBFDE, 2.5±0.7 days, and DRESS, 29.4±5.7 days. The most common drugs implicated were antibiotics (33.3%), followed by allopurinol (18.9%) and anticonvulsant (18.4%). Out of 154 cases of SJS/TEN/overlap syndrome, allopurinol was the commonest causative agents (20.1%). In DRESS, allopurinol accounts for 45.8% of the cases. The mortality rate in SJS, TEN and DRESS were 1.9%, 13.3% and 12.5% respectively. No mortality was observed in AGEP and GBFDE. CONCLUSION: The commonest manifestations of SCARs in our setting were SJS, TEN and DRESS. Allopurinol was the most common culprit. Thus, judicious allopurinol use is advocated and pre-emptive genetic screening for HLAB *5801 should be considered.


Assuntos
Toxidermias/etiologia , Doença Aguda , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/toxicidade , Anticonvulsivantes/toxicidade , Criança , Pré-Escolar , Toxidermias/epidemiologia , Síndrome de Hipersensibilidade a Medicamentos/epidemiologia , Síndrome de Hipersensibilidade a Medicamentos/etiologia , Feminino , Supressores da Gota/toxicidade , Humanos , Malásia/epidemiologia , Masculino , Pessoa de Meia-Idade , Nevo/epidemiologia , Nevo/etiologia , Estudos Retrospectivos , Centros de Atenção Terciária/estatística & dados numéricos , Adulto Jovem
5.
Cancer Gene Ther ; 21(9): 389-96, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25124811

RESUMO

Thymosin beta-4 (Tß4) is known to be involved in tumorigenesis. Overexpression of this polypeptide has been observed in a wide variety of cancers, including colorectal carcinoma (CRC). Accordingly, Tß4 has been proposed to be a novel therapeutic target for CRC, especially in its metastatic form. Although in vitro tumor-suppressive effects of Tß4 gene silencing mediated by small hairpin RNA (shRNA) have already been demonstrated, the in vivo efficacy of such an approach has not yet been reported. Herein, we demonstrated that infection with recombinant adenovirus expressing an shRNA targeting Tß4 markedly reduced the growth of and robustly induced apoptosis in CT-26 mouse CRC cells in culture. Additionally, tumors grown in nude mice from the CT-26 cells whose Tß4 expression already been downregulated by virus infection were also drastically reduced. Most importantly, significant growth arrest of tumors derived from the parental CT-26 cells was observed after multiple intratumoral injections of these viruses. Together, our results show for the first time that in vivo silencing of Tß4 expression by its shRNA generated after adenoviral infection can suppress CRC growth. These results further demonstrate the feasibility of treating CRC by a Tß4 knockdown gene therapeutic approach.


Assuntos
Adenoviridae/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Vetores Genéticos/genética , RNA Mensageiro/genética , RNA Interferente Pequeno/genética , Timosina/genética , Actinas/genética , Actinas/metabolismo , Animais , Apoptose/genética , Ciclo Celular/genética , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Neoplasias Colorretais/metabolismo , Modelos Animais de Doenças , Técnicas de Inativação de Genes , Humanos , Camundongos , Interferência de RNA , Transdução Genética , Carga Tumoral/genética , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Med J Malaysia ; 67(2): 222-3, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22822651

RESUMO

Epidermal growth factor receptor (EGFR)--tyrosine kinase inhibitors (TKI) like erlotinib and gefitinib have been approved as monotherapy for the treatment of patients with locally advanced or metastatic non small cell lung cancer (NSCLC) after failure of at least one prior chemotherapy regimen. The use of EGFR-TKI is associated with unique and dramatic dermatologic side effects. We report 2 patients with NSCLC developing a typical acneiform (papulo-pustular) eruption shortly after initiation of EGFR-TKI.


Assuntos
Adenocarcinoma/tratamento farmacológico , Toxidermias/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Inibidores de Proteínas Quinases/efeitos adversos , Quinazolinas/efeitos adversos , Adulto , Progressão da Doença , Cloridrato de Erlotinib , Feminino , Gefitinibe , Humanos , Masculino , Pessoa de Meia-Idade
7.
Hong Kong Med J ; 17(3): 237-41, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21636872

RESUMO

Haemolytic uraemic syndrome is an important cause of acute renal impairment in childhood. We review the incidence, and clinical and laboratory features of haemolytic uraemic syndrome in a Chinese population. Five patients were identified from 2006 to 2008. All patients were young children with associated invasive Streptococcus pneumoniae pulmonary infection. Serotypes 3, 14, and 19A were confirmed in four patients. The classical post-diarrhoeal form associated with Escherichia coli (O157:H7) infection was not seen. One patient died of acute respiratory failure. Streptococcus pneumoniae infection, as an associated condition in haemolytic uraemic syndrome, is important and relatively common in Chinese patients, especially among children. The acute clinical picture is similar to that reported in the western literature, except for an uncommon association with meningitis. The medium-term renal outcome of the Chinese population appears to be more favourable than the Caucasians. Widespread vaccination against Streptococcus pneumoniae may have resulted in changes in bacterial epidemiology and clinicians should be continuously aware of this severe disease. The use of washed blood components for transfusion in the acute stage requires further study.


Assuntos
Síndrome Hemolítico-Urêmica/microbiologia , Infecções Pneumocócicas/complicações , Streptococcus pneumoniae/isolamento & purificação , Pré-Escolar , China , Feminino , Seguimentos , Humanos , Masculino , Infecções Pneumocócicas/microbiologia , Insuficiência Respiratória/microbiologia , Infecções Respiratórias/microbiologia , Estudos Retrospectivos , Sorotipagem , Índice de Gravidade de Doença , Streptococcus pneumoniae/classificação
9.
Hong Kong Med J ; 17(2): 112-8, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21471590

RESUMO

OBJECTIVE: To evaluate the efficacy and toxicities of stereotactic radiotherapy for unresectable hepatocellular carcinoma. DESIGN: Retrospective study. SETTING: Prince of Wales Hospital, Hong Kong. MAIN OUTCOME MEASURES: Treatment outcome and toxicities. PATIENTS: During the period of 2000 to 2004, 16 patients with hepatocellular carcinoma treated with stereotactic radiotherapy were reviewed. RESULTS: Of the 16 patients, 11 had assessable responses. For local control, there were two complete and three partial responses, five with stable disease and one with progressive disease, giving a local response rate of 45% and control rate of 91%. The median survival was 23 months. The 1-year and 3-year overall survival rates were 62% and 28%, respectively. The most frequent site of recurrence was intrahepatic but outside the irradiated field. Two patients with Child-Pugh B cirrhosis developed radiation-induced liver disease. No other grade 3/4 toxicities were recorded. CONCLUSION: Stereotactic radiotherapy gives high local control rates and has the potential to prolong survival in patients with hepatocellular carcinoma. It is safe and tolerable in Child-Pugh A patients.


Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Radiocirurgia/métodos , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Feminino , Humanos , Fígado/efeitos da radiação , Neoplasias Hepáticas/mortalidade , Masculino , Pessoa de Meia-Idade , Radiocirurgia/efeitos adversos
10.
Med J Malaysia ; 66(4): 383-4, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22299569

RESUMO

Kaposi's sarcoma (KS) is strongly associated with Human Herpes Virus 8 (HHV8) and Human Immunodeficiency Virus infection (HIV). It was the first malignancy to be linked with Acquired Immunodeficiency Syndrome (AIDS). We report a case of Kaposi's sarcoma in a newly diagnosed retroviral homosexual patient with CD4 count of 21. He had multiple firm discrete violaceous plaques and nodules scattered over the face, scalp, hard palate, trunk and genitalia. Biopsy of a skin nodule over the trunk and a biopsy of a lesion from the gastric mucosa confirmed Kaposi's sarcoma. He was started on Highly Active Antiretroviral Therapy (HAART) and cryotherapy (liquid nitrogen) was given for the lesions over the skin. He responded well to treatment. Liquid nitrogen is a useful adjuvant treatment for Kaposi's sarcoma.


Assuntos
Sarcoma de Kaposi/terapia , Adulto , Terapia Antirretroviral de Alta Atividade , Crioterapia , Humanos , Masculino
11.
Neurology ; 75(24): 2185-9, 2010 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-21172841

RESUMO

BACKGROUND: The association between protein S deficiency (PSD) and ischemic stroke is controversial and warrants further investigation. METHODS: We conducted a genotype and MRI correlation study in a Chinese family in which hereditary PSD cosegregated with premature ischemic strokes. Six out of 11 family members inherited PSD type III in an autosomal dominant manner. RESULTS: Among all PSD members, a novel missense mutation 1063C→T in exon 10 of protein S alpha (PROS1) was identified, which encoded a substitution of arginine to cysteine at position 355 (R355C) in the first globular domain of laminin A of protein S. Wild-type PROS1 sequences were retained in non-PSD members. MRI detected deep white matter infarctions predominantly distributed in the borderzone regions. The infarct topography was homogeneous in all adult mutant carriers. By contrast, cerebral infarction was absent in nonmutant carriers. Extensive investigation in the family did not reveal any confounding stroke risk. Haplotype analysis with high-density single nucleotide polymorphism markers revealed a 6.1-Mb minimally rearranged region (rs12494685 to rs1598240) in 3q11.2, lod = 3.0. Among the 7 annotated genes in this region, PROS1 is known to be associated with thrombotic disorders. MRI screening in an additional 10 PSD families without R355C showed no cerebral infarction. CONCLUSIONS: PROS1 R355C mutation cosegregated with PSD type III and premature white matter infarctions in the index family. The findings substantiate an association between PSD and stroke. Study of the mechanism underlying this association may improve our understanding of premature cryptogenic white matter infarction.


Assuntos
Encéfalo/patologia , Infarto Cerebral/genética , Infarto Cerebral/patologia , Mutação de Sentido Incorreto , Deficiência de Proteína S/complicações , Proteína S/genética , Adolescente , Adulto , Idoso , Arginina , Encéfalo/irrigação sanguínea , Criança , Cisteína , Feminino , Predisposição Genética para Doença , Haplótipos , Hong Kong , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Anotação de Sequência Molecular , Linhagem , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Adulto Jovem
12.
Int J Tuberc Lung Dis ; 14(7): 806-18, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20550762

RESUMO

OBJECTIVE: To compare the effects of food and antacids on the bioavailability of first-line anti-tuberculosis drugs. METHOD: Systematic search of electronic databases PubMed (January 1950-May 2009), and the Cochrane Library database (January 1974-May 2009), including the Cochrane Centre register of controlled trials, and ongoing trials from research registers using key terms 'food', 'antacids', 'meal', 'controlled trial', 'diet', and the first-line anti-tuberculosis drugs isoniazid (INH), rifampicin (RMP), ethambutol (EMB) and pyrazinamide (PZA). Meta-analysis was performed using RevMan software 5 to assess the impact of food or antacids on the maximum plasma concentrations (C(max)) and area under the plasma concentration time curve (AUC) of anti-tuberculosis drugs. RESULTS: Twelve trials involving 157 patients were included in the meta-analysis. The overall effects showed that food significantly reduced the C(max) mean difference (C(max) MD; C(max) MD -1.42, 95%CI -1.56--1.28, P < 0.00001) and AUC (C(max) MD -3.33, 95%CI -4.05--2.62, P < 0.00001) of INH but antacids did not. Food also significantly reduced the C(max) MD (C(max) MD -2.47, 95%CI -3.30--1.64, P < 0.00001) but not the AUC of RMP. Antacids had no effect on the C(max) MD or AUC of RMP. The C(max) and AUC of PZA were unaffected by both food and antacids. Both food and antacids reduced the C(max) but not the AUC of EMB. CONCLUSION: From a pharmacokinetic point of view, it seems that the better option for patients with gastrointestinal upsets during chemotherapy would be to add antacids rather than dosing with meals.


Assuntos
Antiácidos/farmacologia , Antituberculosos/farmacocinética , Interações Alimento-Droga , Antituberculosos/administração & dosagem , Área Sob a Curva , Disponibilidade Biológica , Ensaios Clínicos como Assunto , Interações Medicamentosas , Humanos
13.
J Clin Pathol ; 62(12): 1107-11, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19946097

RESUMO

BACKGROUND: Deletions in the beta-globin cluster causing thalassaemia and hereditary persistence of fetal haemoglobin (HPFH) are uncommon and difficult to detect. Data in Chinese are very scarce. AIMS: To use a recently available technique to investigate the frequencies and nature of beta-globin cluster deletions in Chinese. METHODS: 106 subjects with phenotypes of thalassaemia or HPFH and suspected to have deletions in the beta-globin cluster were studied. A commercially available kit employing multiplex ligation-dependent probe amplification (MLPA) was used to screen for deletions. Gap PCR and direct nucleotide sequencing were used to characterise deletions detected. RESULTS: 17 deletions in the beta-globin cluster were found in 17 patients: 8 of Chinese ((A)gammadeltabeta)(0) thalassaemia, 7 of Southeast Asian (Vietnamese) deletion and 2 of Thai ((A)gammadeltabeta)(0) thalassaemia. The only type of deletion detected in deltabeta-thalassaemia was Chinese ((A)gammadeltabeta)(0) thalassaemia. The deletional form of HPFH was rarely seen in only 1 case of Thai ((A)gammadeltabeta)(0) thalassaemia. Deletions presenting as beta-thalassaemia trait and raised HbF were all of the Southeast Asian (Vietnamese) deletion type. When these deletions were co-inherited with classical beta-thalassaemia mutations in compound heterozygous states, the phenotypes could be very variable. CONCLUSIONS: In the Chinese population, there are only relatively few types of deletions seen in the beta-globin cluster. MLPA is a fast and effective way of screening for these deletions. Characterisation of these deletions allows the development of simpler and more specific PCR-based tests for routine diagnostic use. Accurate prediction of phenotype is not always feasible. The molecular defects in many cases of HPFH still await discovery.


Assuntos
Deleção de Genes , Família Multigênica/genética , Globinas beta/genética , Talassemia beta/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/genética , Criança , Pré-Escolar , Feminino , Hemoglobina Fetal/análise , Genótipo , Hemoglobinopatias/etnologia , Hemoglobinopatias/genética , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Técnicas de Amplificação de Ácido Nucleico/métodos , Fenótipo , Talassemia/genética , Adulto Jovem , Talassemia beta/etnologia
14.
Leukemia ; 23(8): 1490-9, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19262598

RESUMO

Chromosomal rearrangements of the human MLL gene are associated with high-risk pediatric, adult and therapy-associated acute leukemias. These patients need to be identified, treated appropriately and minimal residual disease was monitored by quantitative PCR techniques. Genomic DNA was isolated from individual acute leukemia patients to identify and characterize chromosomal rearrangements involving the human MLL gene. A total of 760 MLL-rearranged biopsy samples obtained from 384 pediatric and 376 adult leukemia patients were characterized at the molecular level. The distribution of MLL breakpoints for clinical subtypes (acute lymphoblastic leukemia, acute myeloid leukemia, pediatric and adult) and fused translocation partner genes (TPGs) will be presented, including novel MLL fusion genes. Combined data of our study and recently published data revealed 104 different MLL rearrangements of which 64 TPGs are now characterized on the molecular level. Nine TPGs seem to be predominantly involved in genetic recombinations of MLL: AFF1/AF4, MLLT3/AF9, MLLT1/ENL, MLLT10/AF10, MLLT4/AF6, ELL, EPS15/AF1P, MLLT6/AF17 and SEPT6, respectively. Moreover, we describe for the first time the genetic network of reciprocal MLL gene fusions deriving from complex rearrangements.


Assuntos
Leucemia/genética , Proteína de Leucina Linfoide-Mieloide/genética , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/genética , Recombinação Genética , Translocação Genética , Doença Aguda , Adulto , Biópsia , Medula Óssea/química , Medula Óssea/patologia , Criança , Quebra Cromossômica , Cromossomos Humanos Par 11/genética , Cromossomos Humanos Par 11/ultraestrutura , Biologia Computacional , DNA de Neoplasias/sangue , DNA de Neoplasias/genética , Duplicação Gênica , Histona-Lisina N-Metiltransferase , Humanos , Reação em Cadeia da Polimerase
15.
J Med Genet ; 45(11): 745-51, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18697826

RESUMO

BACKGROUND: Fetal haemoglobin (HbF) level modifies the clinical severity of HBB disorders. Intergenic variants of HBS1L-MYB on chromosome 6q23 have recently been shown to be a major quantitative trait locus (QTL) influencing HbF levels in normal Caucasian adults. METHODS: A unique and well-characterised cohort of 238 Chinese subjects with beta-thalassaemia trait was used to conduct a single-nucleotide polymorphism (SNP) association study for HbF level. RESULTS: Within this locus, 29 trait-associated SNPs in a non-coding 56 kb segment were identified. They were divided into five linkage disequilibrium (LD) blocks in the Chinese participants. CONCLUSIONS: The data independently validate for the first time the significance of the HBS1L-MYB intergenic region in regulating HbF expression in a separate ethnic group that has a high prevalence of beta-thalassaemia. Functional studies to unravel the biological significance of this region in regulating HbF production is clearly indicated, which may lead to new strategies to modify the disease course of severe HBB disorders.


Assuntos
Cromossomos Humanos Par 6/genética , DNA Intergênico/genética , Hemoglobina Fetal/metabolismo , Regulação da Expressão Gênica , Locos de Características Quantitativas/genética , Talassemia beta/genética , Adolescente , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China , Estudos de Coortes , Feminino , Hemoglobina Fetal/genética , Humanos , Lactente , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética , Adulto Jovem
17.
Pediatr Hematol Oncol ; 25(3): 227-31, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18432506

RESUMO

An extended family with three individuals affected by two different forms of double heterozygosity for beta-thalassemia and Hb New York is reported. Double heterozygosity of Hb New York [beta 113 GTG-->GAG; VAL-->GLU] and beta degrees codon 17 was detected in a fetus following prenatal screening for thalassemia. The father and a paternal aunt were also found to be heterozygous for Hb New York and beta degrees IVSII-654. Both adults had clinical and hematological features consistent with beta-thalassemia trait. The affected child was followed up after birth and manifested the typical course of a thalassemia trait, with no signs of organomegaly or overt hemolysis. Observations strongly suggest that double heterozygosity of Hb New York and beta degrees thalassemia has mild, if any, clinical symptoms, and is not an indication of therapeutic abortion when detected antenatally.


Assuntos
Hemoglobinas Anormais/genética , Mutação , Locos de Características Quantitativas/genética , Talassemia beta/genética , Adulto , Feminino , Heterozigoto , Humanos , Recém-Nascido , Masculino
18.
Leuk Res ; 32(9): 1374-81, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18372040

RESUMO

The functional behavior of hematopoietic stem cell (HSC) and progenitors in chronic myelomonocytic leukemia (CMML) and on disease progression is little known. We performed cell proliferation, apoptosis, hematopoietic colony forming/replating and differentiation potential studies in the purified subpopulations of Lin(-)CD34(+)CD38(-) and Lin(-)CD34(+)CD38(+) cells from 16 CMML with 6 cases after acute myeloid leukemia transformation (AML-t). We observed an expansion of the hematopoietic progenitor pool (Lin(-)CD34(+) cells) in AML-t comprising mainly Lin(-)CD34(+)CD38(+) cells. The Lin(-)CD34(+)CD38(+) cells in AML-t displayed high proliferative activity, resistance to apoptosis, enhanced myeloid colony formation/replating ability and a complete dendritic cell (DC) differentiation block. Our findings suggest Lin(-)CD34(+)CD38(+) cells instead of Lin(-)CD34(+)CD38(-) cells could be the target(s) of secondary genetic lesions underpinning progression from CMML to AML, which have implications for the further study of the biology of leukemic transformation and the design of new strategies for the effective treatment of CMML.


Assuntos
ADP-Ribosil Ciclase 1/metabolismo , Antígenos CD34/metabolismo , Leucemia Mieloide Aguda/metabolismo , Leucemia Mielomonocítica Crônica/metabolismo , Glicoproteínas de Membrana/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose/fisiologia , Ciclo Celular/fisiologia , Proliferação de Células , Transformação Celular Neoplásica , Ensaio de Unidades Formadoras de Colônias , Células Dendríticas/metabolismo , Progressão da Doença , Citometria de Fluxo , Fator Estimulador de Colônias de Granulócitos/administração & dosagem , Células-Tronco Hematopoéticas , Humanos , Leucemia Mieloide Aguda/patologia , Leucemia Mielomonocítica Crônica/patologia , Pessoa de Meia-Idade , Fator de Necrose Tumoral alfa/farmacologia
19.
J Leukoc Biol ; 83(1): 173-80, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17895399

RESUMO

Dendritic cells (DCs), as specialized APCs, play a key role in the induction of anti-tumor immunity. They originate from bone marrow (BM) progenitors, which are frequently the targets of chromosomal translocations leading to development of leukemia. Aberrant DC differentiation and functions have been observed and are widely reported in patients with leukemia. It is not clear, however, whether such defects are a direct effect of a leukemic fusion gene or simply an outcome of the clinical disease. In this study, we demonstrate for the first time that knockin of the Mll-Een fusion gene can affect myeloid DC differentiation and functions directly, independent of the leukemic disease activities. We showed that the Mll-Een-expressing BM cells [enhanced green fluorescent protein+ (EGFP+)] from leukemic and nonleukemic mice had similarly impaired DC differentiation capacities with functional abnormalities. In contrast, BM cells without Mll-Een expression (EGFP(-)) showed normal DC differentiation and functions. A reduction in the frequency of CD11c+ DCs was also observed within the EGFP+ population in spleen and lymph nodes, and these cells were dysfunctional. Taken together, our findings suggest that the Mll-Een fusion gene can affect myeloid DC differentiation directly and functions in a cell-autonomous manner, where fully leukemic transformation of the hematopoietic progenitors is not required exclusively. Therefore, the study provides evidence for a direct causal relationship between leukemic gene fusion and abnormal DC differentiation, possibly contributing to the development of leukemia.


Assuntos
Transformação Celular Neoplásica/genética , Células Dendríticas/imunologia , Leucemia/genética , Proteína de Leucina Linfoide-Mieloide/genética , Animais , Diferenciação Celular/genética , Diferenciação Celular/imunologia , Movimento Celular/imunologia , Transformação Celular Neoplásica/imunologia , Células Cultivadas , Citocinas/biossíntese , Citometria de Fluxo/métodos , Leucemia/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína de Leucina Linfoide-Mieloide/metabolismo , Linfócitos T/imunologia
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