Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 32
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
J Arthroplasty ; 2023 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-38081552

RESUMO

BACKGROUND: The patient acceptable symptom state (PASS) refers to a cutoff value on any patient-reported outcome measures (PROMs) scale, beyond which patients consider themselves as having achieved an acceptable outcome. This study aimed to identify PASS thresholds for knee-specific and generic PROMs at 10 years post-unicompartmental knee arthroplasty (UKA). METHODS: There were 269 patients who underwent UKA for medial osteoarthritis from 2004 to 2007 at a single institution and were surveyed preoperatively and 10 years postoperatively using the Knee Society Function Score (KSFS), Knee Society Knee Score (KSKS), Oxford Knee Score (OKS), 36-Item Short Form Survey (SF-36) Mental Component Score (MCS), and SF-36 Physical Component Score (PCS). Treatment outcomes and expectations were assessed using an anchor question, and PASS attainment was determined using the Youden index on a receiver operating characteristic (ROC) curve. Also, a similar study that identified 2-year long-term PROM PASS thresholds for UKA was referenced and compared. RESULTS: Overall, 91.1% reported acceptable outcomes. The area under the curve for ROCs of KSKS, OKS, and PCS were 0.80, 0.75, and 0.71, respectively. The area under the curve for ROCs of KSFS and MCS were both 0.64. The PASS thresholds were 67.5 for KSFS, 70.5 for KSKS, 39.5 for OKS, 44.6 for PCS, and 43.8 for MCS. Patients who achieved a PASS were at least 3 times more likely to have satisfactory outcomes. CONCLUSIONS: To our knowledge, this is the first study that identified 10-year long-term PROM PASS thresholds for UKA. Accounting for our finding that a decade-long follow-up yielded lower PASS thresholds, time-specific UKA PROM PASS thresholds should be considered. LEVEL OF EVIDENCE: III.

2.
Med J Malaysia ; 78(1): 80-86, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36715196

RESUMO

INTRODUCTION: The COVID-19 pandemic has reached a phase where many have been infected at least once. Healthcare workers were not spared from being infected. This study aimed to determine the period prevalence of COVID-19 among the paediatric healthcare workers in Negeri Sembilan as the country transitioned into an endemic phase of the pandemic. Additionally, we investigate potential sociodemographic and occupational characteristics associated with SARS-CoV-2 infection among healthcare workers. MATERIALS AND METHODS: A cross-sectional study was conducted among the healthcare workers in the paediatric department at three public specialist hospitals in Negeri Sembilan between 15 and 21 April 2022. Data were collected through a self-administered questionnaire. RESULTS: Out of the 504 eligible healthcare workers, 493 participated in this study (response rate 97.8%). The overall prevalence of COVID-19 (11 March 2020-15 April 2022) among healthcare workers was 50.9%. The majority (80.1%) were infected during the Omicron wave two months before the survey. Household contacts accounted for 35.9% of infection sources. The proportion of non-doctors in the COVID-19-infected group was significantly higher compared to the non-infected group (74.1% vs 64.0%, p=0.016). The COVID-19-infected group had a higher proportion of schoolgoing children (44.6% vs 30.6%, p=0.001) and children who attended pre-school/sent to the babysitter (49.0% vs 24.4%, p<0.001). There were no significant differences between infection rates among the healthcare workers working in the tertiary hospital and the district hospitals. There were also no significant differences in the proportion of COVID-19- infected doctors and nurses when analysed by seniority. CONCLUSION: Our study provided an estimate on the prevalence of COVID-19 among paediatric healthcare workers in Negeri Sembilan and the factors associated with infection, which captures the extent and magnitude of this pandemic on the state's paediatric department. Most infections resulted from household contact, with a higher proportion of infected healthcare workers having young children.


Assuntos
COVID-19 , Humanos , Criança , Pré-Escolar , COVID-19/epidemiologia , Estudos Transversais , Prevalência , SARS-CoV-2 , Pandemias , Pessoal de Saúde
3.
Med J Malaysia ; 75(1): 38-42, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32008018

RESUMO

INTRODUCTION: Cerebral venous sinus thrombosis (CVST) is a potentially fatal neurological condition. However, due to the non-specific clinical and radiological features of CVST, it can sometimes result in a delay in the diagnosis and subsequent management. The aim of this study was to evaluate the demography, risk factors and one-year outcome of CVST patients treated in Hospital Universiti Sains Malaysia. METHODS: In this retrospective study, we reviewed the cases diagnosed with CVST admitted to our centre from January 2011 until November 2015. RESULTS: A total of 15 patients were included in this review. The patterns of imaging findings as well as risk factors for CVST is discussed with a review of the literature and current management practices. One year followed-up showed full recovery (Glasgow Outcome Scale (GOS) of 5) in 10 cases (66.7%), whereas 4 cases (26.7%) with GOS of 4 (three cases with neurological deficits, and 1 case with mild symptom. There was one case of mortality in this study secondary to sepsis during hospitalisation. The presenting symptoms were mainly headache, focal neurology deficits, seizure and altered sensorium. Risk factors identified were oral contraceptive pills usage, chronic sinuses or ear infections, and obesity. Initial computed tomography (CT) scan showed various findings and haemorrhagic infarct was one of the common findings. Magnetic resonance imaging (MRI) and magnetic resonance venography (MRV) revealed majority of the patients had occlusion at two or more venous sinus sites. No patients had new or recurrent intracranial haemorrhage following initiation of anticoagulation therapy. CONCLUSION: Thus it is considerable safe to start anticoagulation therapy in CVST patients including those with intracranial haemorrhage. We propose further neuroimaging to avoid missed diagnosis of CVST in patient presented with recent onset headache and CT evidence of unusual cerebral infarction.


Assuntos
Trombose dos Seios Intracranianos/diagnóstico , Trombose dos Seios Intracranianos/tratamento farmacológico , Adolescente , Adulto , Anticoagulantes/administração & dosagem , Feminino , Humanos , Malásia , Masculino , Auditoria Médica , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Estudos Retrospectivos , Fatores de Risco , Trombose dos Seios Intracranianos/etiologia , Adulto Jovem
4.
Opt Express ; 23(24): 31286-94, 2015 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-26698755

RESUMO

We present a pilot demonstration of an optical fiber based refractive index (RI) sensor involving the deposition of graphene onto the surface of a segment of a photonic crystal fiber (PCF) in a fiber-based Mach-Zehnder Interferometer (MZI). The fabrication process is relatively simple and only involves the fusion splicing of a PCF between two single mode fibers. The deposition process relies only on the cold transfer of graphene onto the PCF segment, without the need for further physical or chemical treatment. The graphene overlay modified the sensing scheme of the MZI RI sensor, allowing the sensor to overcome limitations to its detectable RI range due to free spectral range issues. This modification also allows for continuous measurements to be obtained without the need for reference values for the range of RIs studied and brings to light the potential for simultaneous dual parameter sensing. The sensor was able to achieve a RI sensitivity of 9.4 dB/RIU for the RIs of 1.33-1.38 and a sensitivity of 17.5 dB/RIU for the RIs of 1.38-1.43. It also displayed good repeatability and the results obtained were consistent with the modeling.

5.
Med J Malaysia ; 69(2): 86-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25241818

RESUMO

Subtentorial subdural empyema is a rare and life threatening intracranial suppuration. It is usually an intracranial complication of otogenic infections. Early diagnosis and surgical drainage are the most important factors determining prognosis. The high mortality reported in the literature reflects the severity of subtentorial subdural empyema if proper management is delayed. Intracranial infections usually require between 4 to 6 weeks of intravenous antibiotics therapy. However, the prolonged duration of hospitalization as well as requirement for neurosurgically inserted indwelling devices may predispose these patients to new nosocomial infections.

6.
J Laryngol Otol ; 137(12): 1378-1383, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37606526

RESUMO

OBJECTIVE: Complications of parotidectomy can have a massive impact on patients' quality of life. This study aimed to evaluate the readability and quality of online health information on parotidectomy. METHOD: The search terms 'parotidectomy', 'parotid surgery', 'parotidectomy patient information' and 'parotid surgery patient information' were parsed through three popular search engines. RESULTS: The websites were analysed using readability scores of the Flesch Reading Ease test and the Gunning Fog Index. The DISCERN instrument was used to assess quality and reliability. The average Flesch Reading Ease score was 50.2 ± 9.0, indicating that the materials were fairly difficult to read, the Gunning Fog Index score showed that the patient health information was suitable for an individual above 12th grade level, and the DISCERN score indicated that the online patient health information had fair quality. The Kruskal-Wallis test showed a significant difference in Flesch Reading Ease and DISCERN tool scores according to website category (p < 0.05). CONCLUSION: Current online patient health information on parotidectomy is too difficult for the public to understand, and it exceeds the reading levels recommended by Health Education England and the American Medical Association.


Assuntos
Compreensão , Informação de Saúde ao Consumidor , Estados Unidos , Humanos , Reprodutibilidade dos Testes , Qualidade de Vida , Ferramenta de Busca , Internet
7.
Med J Malaysia ; 67(6): 613-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23770956

RESUMO

Metastasis of an atrial myxoma to the brain is extremely rare. Thus far there are only 17 cases reported, including our present case. Most of the brain metastases manifest only in 3 to 6 decades, after an average time frame of one to two years after surgical removal of parental tumour. We present a case of brain metastases of atrial myxoma in a teenager of the youngest age among all reported cases, unusually as early as 15 years old. The progress of the metastatic process had been insidious for three years after heart surgery, The imaging demonstrated a rather sizeable tumour by the time when the patient is symptomatic. The location of the metastatic tumour is anyhow superficial to the cortical surface, enabling complete surgical excision of the tumour easily achievable with favourable outcome.


Assuntos
Neoplasias Cardíacas , Mixoma , Encéfalo , Neoplasias Encefálicas/cirurgia , Humanos
8.
Clin Genet ; 80(3): 287-92, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20950398

RESUMO

Autosomal-dominant polycystic kidney disease (ADPKD) is a heterogeneous genetic disorder characterized by abnormal proliferation of renal tubular epithelium, leading to massive kidney enlargement and progressive chronic kidney disease. ADPKD is caused by mutations in PKD1 and PKD2 genes. Herein, we describe and characterize a novel missense mutation in the PKD2 gene (c.1320G>T) in a 41-year-old White man with kidney cysts and a family history of ADPKD. This mutation abolishes a conserved acceptor splice site of intron 5, resulting in a premature termination following the addition of three aberrant amino acids (PKD2 p.L441C fsX4). We demonstrate that the aberrantly spliced transcript is found in substantial amounts in the patient's peripheral blood leukocytes (PBL), and show that this alternative splicing of exon 6 occurs, to a lesser magnitude, in other patients with ADPKD and in normal control individuals. The biological and clinical significance of this splice variant in ADPKD is currently unknown.


Assuntos
Cistos/genética , Falência Renal Crônica/genética , Rim/patologia , Mutação de Sentido Incorreto , Rim Policístico Autossômico Dominante/genética , Canais de Cátion TRPP/genética , Adulto , Cistos/patologia , Análise Mutacional de DNA , Éxons , Humanos , Falência Renal Crônica/diagnóstico por imagem , Falência Renal Crônica/etiologia , Masculino , Dados de Sequência Molecular , Rim Policístico Autossômico Dominante/complicações , Rim Policístico Autossômico Dominante/diagnóstico por imagem , Sítios de Splice de RNA , Splicing de RNA , Canais de Cátion TRPP/metabolismo , Ultrassonografia
9.
Oxf Med Case Reports ; 2020(2): omaa010, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32128221

RESUMO

Haemobilia describes blood loss from the biliary tract and classically presents as Quincke's triad: upper gastrointestinal bleeding (UGIB), jaundice and right upper quadrant abdominal pain. We discuss the case of a 70-year-old male with a previously stented Bismuth 1 hilar cholangiocarcinoma who presented with haematemesis. He had a similar presentation a month ago where a forward viewing gastroscope identified fresh and altered blood in the distal stomach but no clear source of bleeding. During this admission, a side-viewing duodenoscope identified bleeding from the periampullary region, which was managed by inserting a fully covered self-expanding metal stent (fcSEMS) within his pre-existing uncovered SEMS to tamponade the haemorrhage. This case highlights the importance of using a side-viewing duodenoscope for patients with UGIB on a background of a stented cholangiocarcinoma and inserting a fcSEMS within an uncovered SEMS is feasible and effective in managing these patients.

10.
J Dev Orig Health Dis ; 9(2): 172-181, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29039296

RESUMO

Insulin-like growth factor 1 (IGF1) is a regulator of human growth during infancy and childhood, known to promote bone and muscle growth as well as lipid accumulation. This study aimed to investigate the effects of formula milk with or without IGF1 supplementation (in the form of pure IGF1 or bovine colostrum) on growth and body composition in infant cynomolgus macaques during the first 6 months of life. Three groups of infants were nursery-reared and received formula milk with or without IGF1 or bovine colostrum supplementation for 4 months, and a fourth group consisting of breast-fed infants was included for comparison (n=6 for each group). Ranked-based analysis of covariance was used to detect differences between adjusted means for sex. No differences in weight, height, fat mass, and fat-free mass could be detected between groups. However, bone mineral density (BMD) was significantly different between groups at the end of formula feeding. Infants that received bovine colostrum supplementation displayed higher mean BMD than infants of all other groups, with no differences between the latter three groups. In conclusion, our results suggest that supplementation with bovine colostrum can enhance BMD in formula-fed infants, an effect that apparently does not depend on IGF1. Bovine colostrum supplementation could be beneficial for long-term bone health in infants with suboptimal bone growth.


Assuntos
Densidade Óssea/efeitos dos fármacos , Colostro , Fator de Crescimento Insulin-Like I/administração & dosagem , Leite Humano , Animais , Animais Recém-Nascidos , Composição Corporal/efeitos dos fármacos , Composição Corporal/fisiologia , Densidade Óssea/fisiologia , Bovinos , Colostro/fisiologia , Feminino , Humanos , Macaca fascicularis , Masculino , Leite Humano/fisiologia , Gravidez
11.
Phytochemistry ; 114: 168-77, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25457484

RESUMO

Basal stem rot (BSR) of oil palm roots is due to the invasion of fungal mycelia of Ganoderma species which spreads to the bole of the stem. In addition to root contact, BSR can also spread by airborne basidiospores. These fungi are able to break down cell wall components including lignin. BSR not only decreases oil yield, it also causes the stands to collapse thus causing severe economic loss to the oil palm industry. The transmission and mode of action of Ganoderma, its interactions with oil palm as a hemibiotroph, and the molecular defence responses of oil palm to the infection of Ganoderma boninense in BSR are reviewed, based on the transcript profiles of infected oil palms. The knowledge gaps that need to be filled in oil palm-Ganoderma molecular interactions i.e. the associations of hypersensitive reaction (HR)-induced cell death and reactive oxygen species (ROS) kinetics to the susceptibility of oil palm to Ganoderma spp., the interactions of phytohormones (salicylate, jasmonate and ethylene) at early and late stages of BSR, and cell wall strengthening through increased production of guaiacyl (G)-type lignin, are also discussed.


Assuntos
Ganoderma/fisiologia , Óleos de Plantas/química , Ganoderma/química , Ganoderma/genética , Óleo de Palmeira , Óleos de Plantas/farmacologia , Raízes de Plantas/química , Esporos Fúngicos/química , Esporos Fúngicos/genética
12.
J Med Chem ; 33(9): 2412-20, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2167978

RESUMO

A series of 1-, 2-, 3-, 4-, 5-, 6-, 7-, 10-, and 12-substituted pyridodiindoles were synthesized and screened in vitro against [3H]diazepam for activity at the benzodiazepine receptor (BzR). In vitro, the 2-substituted pyridodiindoles were found to be the most potent (IC50 less than 10 nM) of this new class of BzR ligands. In vivo, 2-methoxypyridodiindole 19a (IC50 = 8 nM) was found to be the most potent partial inverse agonist (proconvulsant) of the series. The parent compound 2 (IC50 = 4 nM) was only slightly less potent. In addition, 2-hydroxypyridodiindole 21a (IC50 = 6 nM) was found to exhibit potent proconvulsant activity when administered as a prodrug derivative, pivaloyl ester 22. 2-Chloropyridodiindole 16a (IC50 = 10 nM) was devoid of preconvulsant activity; however, 16a was found to be the most potent antagonist of the anticonvulsant effects of diazepam in this class of BzR ligands. From the in vivo data available, substitution on ring E of 2 with electron-withdrawing groups results in antagonists at BzR, while replacement of hydrogen at C-2 with electron-releasing groups provides enhanced inverse agonist activity. The pyridodiindoles were used as "templates" for the formulation of a model of the inverse agonist/antagonist active site of the BzR. The proposed model consists of a hydrogen bond acceptor site (A1) and a hydrogen bond donor site (D2) disposed 6.0-8.5 A from each other on the receptor protein. The hydrogen-bonding sites are believed to be located at the base of a narrow cleft. A large lipophilic pocket at the mouth of the narrow cleft serves to direct molecules into the binding site, while the presence of a small lipophilic pocket permits substitution only at position 2 of the pyridodiindole nucleus for maximum binding potency.


Assuntos
Convulsivantes/síntese química , Di-Hidropiridinas/síntese química , Indóis/síntese química , Animais , Sítios de Ligação , Fenômenos Químicos , Química , Convulsivantes/farmacologia , Di-Hidropiridinas/farmacologia , Indóis/farmacologia , Ligantes , Masculino , Camundongos , Ratos , Ratos Endogâmicos , Receptores de GABA-A/efeitos dos fármacos , Relação Estrutura-Atividade
13.
J Med Chem ; 33(9): 2343-57, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2167977

RESUMO

The structural requirements for ligand binding to the benzodiazepine receptor (BzR) inverse agonist site were probed through the synthesis and in vitro evaluation of 3-substituted beta-carbolines 6, 7, 11, 12, gamma-carboline 13, and diindoles 18-21, 23-25, 27, 28, and 34. On the basis of the apparent binding affinities of these and other analogues, a hydrogen bond acceptor site (A2) on the receptor is proposed to interact with the N(9) hydrogen atom of the beta-carbolines or the N(7) hydrogen nuclei of the diindoles. Likewise, a proposed hydrogen bond donating site (H1) interacts with the N(2) nitrogen atom of the beta-carbolines or the N(5) nitrogen atom of the diindoles. It appears that interaction with both sites is a prerequisite for high affinity since analogues which have either one or both of these positions blocked exhibit substantial reduction in affinity. Moreover, H1 appears to be capable of engaging in a three-centered hydrogen bond with appropriately functionalized ligands, which explains the increase in potency observed in the following series of 3-substituted beta-carbolines: the n-butyl (12, IC50 = 245 nM), n-propoxy (9, IC50 = 11 nM), and propyl ketone (11, IC50 = 2.8 nM) congeners. In addition to H1 and A2, there appears to be a relatively narrow hydrophobic pocket in the binding cleft that can accommodate substituents at the 3-position of the beta-carbolines which have chain lengths less than or equal to C5. There is a 1 order of magnitude decrease in affinity between n-propoxy analogue 9 (IC50 = 11 nM, chain length = 4) and n-butoxy derivative 7 (IC50 = 98 nM, chain length = 5). Furthermore, alpha- and gamma-branching [e.g. ethoxycarbonyl (2), IC50 = 5 nM and tert-butoxycarbonyl (31) IC50 = 10 nM] but not beta- and delta-branching [e.g. isopropoxy (6), IC50 = 500 nM and (neopentyloxy) carbonyl (48), IC50 = 750 nM] at position 3 are tolerated. Occupation of this hydrophobic pocket is clearly important for high affinity as evidenced by the relatively low affinity of 30, a beta-carboline which possesses a hydrogen atom at the 3-position. This same hydrophobic pocket is partially filled by the D and E rings of the diindoles, which accounts for the high affinity of several members of this series. An excluded volume analysis using selected 3-substituted beta-carbolines and ring-E substituted pyridodiindoles is consistent with the presence of this hydrophobic pocket (see Figure 1).(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Carbolinas/síntese química , Simulação por Computador , Modelos Químicos , Receptores de GABA-A/metabolismo , Sítios de Ligação , Carbolinas/metabolismo , Fenômenos Químicos , Química , Ligantes , Estereoisomerismo , Relação Estrutura-Atividade
14.
J Med Chem ; 35(22): 4105-17, 1992 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-1331457

RESUMO

A series of rigid planar azadiindoles (8a, 8b, and 8d), benzannelated pyridodiindoles (11a, 11b, and 11d), and indolopyridoimidazoles (11c, 20, and 24) were synthesized from 4-oxo-1,2,3,4-tetrahydro-beta-carboline 5 via the Fischer indole cyclization with the appropriate arylhydrazines. These analogues were employed as probes ("molecular yardsticks") to define the spatial dimensions of the lipophilic regions of the benzodiazepine receptor (BzR) binding cleft. Benzannelated indoles 11a-d and indolopyridoimidazoles 20 and 24 were important in establishing an area of negative interaction (S1, see Figure 6, part b) in the binding cleft common to the interactions of both inverse agonists and agonists. Data from this chemical and computer-assisted analysis of the pharmacophore (see Figure 6) indicates that inverse agonists and agonists bind to the same binding region, but the pharmacophoric descriptors required for the two activities are different, in keeping with previous studies with these planar ligands. However, the hydrogen bond donating site H1 and the lipophilic region L1 in the receptor binding site are common interactions experienced by both series of ligands. The low affinities of both indolo[3,2-c]carbazole (3a) and indolo[3,2-b]isoquinoline (3b) for the BzR are consonant with the requirements of a hydrogen bond acceptor interaction at donor site H1 and a hydrogen bond donor interaction at acceptor site A2 for potent inverse agonist activity in the beta-carboline series. The hydrochloride salts of 1-aza- 8a (IC50 10.6 nM), 2-aza- 8b (IC50 51.5 nM), and 4-azadiindole 8d (IC50 11.2 nM) were found to be much more soluble in water than the corresponding salt of the parent diindole 2. Moreover, aza analogues 8a and 8b were shown to be partial inverse agonists with proconvulsant potencies comparable to that of the parent diindole 2.


Assuntos
Carbolinas/síntese química , Indóis/síntese química , Sondas Moleculares/síntese química , Receptores de GABA-A/química , Animais , Ligação Competitiva , Carbolinas/metabolismo , Ciclização , Técnicas In Vitro , Indóis/metabolismo , Ligantes , Masculino , Camundongos , Modelos Moleculares , Conformação Molecular , Sondas Moleculares/metabolismo , Ratos , Receptores de GABA-A/efeitos dos fármacos , Receptores de GABA-A/metabolismo , Relação Estrutura-Atividade , Moldes Genéticos
15.
FEMS Immunol Med Microbiol ; 34(4): 267-75, 2002 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-12443826

RESUMO

Neisseria meningitidis expresses a range of lipooligosaccharide (LOS) structures, comprising of at least 13 immunotypes (ITs). Meningococcal LOS is subject to phase variation of its terminal structures allowing switching between ITs, which is proposed to have functional significance in disease. The objectives of this study were to investigate the repertoire of structures that can be expressed in clinical isolates, and to examine the role of phase-variable expression of LOS genes during invasive disease. Southern blotting was used to detect the presence of LOS biosynthetic genes in two collections of meningococci, a global set of strains previously assigned to lineages of greater or lesser virulence, and a collection of local clinical isolates which included paired throat and blood isolates from individual patients. Where the phase-variable genes lgtA, lgtC or lgtG were identified, they were amplified by PCR and the homopolymeric tracts, responsible for their phase-variable expression, were sequenced. The results revealed great potential for variation between alternate LOS structures in the isolates studied, with most strains capable of expressing several alternative terminal structures. The structures predicted to be currently expressed by the genotype of the strains agreed well with conventional immunotyping. No correlation was observed between the structural repertoire and virulence of the isolate. Based on the potential for LOS phase variation in the clinical collection and observations with the paired patient isolates, our data suggest that phase variation of LOS structures is not required for translocation between distinct compartments in the host.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica , Variação Genética , Lipopolissacarídeos/biossíntese , Neisseria meningitidis/patogenicidade , Proteínas de Bactérias/química , Genótipo , Humanos , Lipopolissacarídeos/química , Infecções Meningocócicas/microbiologia , Neisseria meningitidis/genética , Neisseria meningitidis/crescimento & desenvolvimento , Fenótipo , Reação em Cadeia da Polimerase , Análise de Sequência de DNA
16.
Ann Acad Med Singap ; 14(4): 689-92, 1985 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-4083808

RESUMO

In 1980, 118 patients with psoriasis were admitted to the inpatient service of MRH resulting in 3048 patient days of hospitalisation. The day care centre for psoriasis can provide an efficient therapeutic environment thus reducing hospital admissions. The outpatient dithranol-ultraviolet B combination therapy gave a 80% success in clearing 95% of the skin of psoriasis. PUVA therapy gave a clearance of 77% requiring an average of 25 treatment sessions; taking an average of 42 days and total UVA dose of 346 J/cm2. Combination therapy of retinoids and PUVA (REPUVA) gave a success rate of 96% clearance with an average of 18 treatment sessions and average total UVA dose of 142 J/cm2.


Assuntos
Hospital Dia , Terapia PUVA , Psoríase/tratamento farmacológico , Assistência Ambulatorial , Antralina/uso terapêutico , Etretinato/uso terapêutico , Humanos , Psoríase/terapia
17.
Leukemia ; 26(2): 236-43, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21860433

RESUMO

TG02 is a novel pyrimidine-based multi-kinase inhibitor that inhibits CDKs 1, 2, 7 and 9 together with JAK2 and FLT3. It dose-dependently inhibits signaling pathways downstream of CDKs, JAK2 and FLT3 in cancer cells with the main targets being CDKs. TG02 is anti-proliferative in a broad range of tumor cell lines, inducing G1 cell cycle arrest and apoptosis. Primary cultures of progenitor cells derived from acute myeloid leukemia (AML) and polycythemia vera patients are very sensitive to TG02. Comparison with reference inhibitors that block only one of the main targets of TG02 demonstrate the benefit of combined CDK and JAK2/FLT3 inhibition in cell lines as well as primary cells. In vivo, TG02 exhibits favorable pharmacokinetics after oral dosing in xenograft models and accumulates in tumor tissues, inducing an effective blockade of both CDK and STAT signaling. TG02 induces tumor regression after oral dosing on both daily and intermittent schedules in a murine model of mutant-FLT3 leukemia (MV4-11) and prolongs survival in a disseminated AML model with wild-type FLT3 and JAK2 (HL-60). These data demonstrate that TG02 is active in various models of leukemia and provide a rationale for the ongoing clinical evaluation of TG02 in patients with advanced leukemias.


Assuntos
Antineoplásicos/farmacologia , Quinases Ciclina-Dependentes/antagonistas & inibidores , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Janus Quinase 2/antagonistas & inibidores , Leucemia Mieloide Aguda/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacologia , Tirosina Quinase 3 Semelhante a fms/antagonistas & inibidores , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Transformada , Modelos Animais de Doenças , Feminino , Compostos Heterocíclicos de 4 ou mais Anéis/uso terapêutico , Humanos , Leucemia Mieloide Aguda/patologia , Camundongos , Camundongos Endogâmicos BALB C , Inibidores de Proteínas Quinases/uso terapêutico
18.
Blood Cancer J ; 1(11): e44, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22829080

RESUMO

FMS-like tyrosine kinase 3 (FLT3) is the most commonly mutated gene found in acute myeloid leukemia (AML) patients and its activating mutations have been proven to be a negative prognostic marker for clinical outcome. Pacritinib (SB1518) is a tyrosine kinase inhibitor (TKI) with equipotent activity against FLT3 (IC(50)=22 n) and Janus kinase 2 (JAK2, IC(50)=23 n). Pacritinib inhibits FLT3 phosphorylation and downstream STAT, MAPK and PI3 K signaling in FLT3-internal-tandem duplication (ITD), FLT3-wt cells and primary AML blast cells. Oral administration of pacritinib in murine models of FLT3-ITD-driven AML led to significant inhibition of primary tumor growth and lung metastasis. Upregulation of JAK2 in FLT3-TKI-resistant AML cells was identified as a potential mechanism of resistance to selective FLT3 inhibition. This resistance could be overcome by the combined FLT3 and JAK2 activities of pacritinib in this cellular model. Our findings provide a rationale for the clinical evaluation of pacritinib in AML including patients resistant to FLT3-TKI therapy.

19.
Leukemia ; 25(11): 1751-9, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21691275

RESUMO

SB1518 is an innovative pyrimidine-based macrocycle that shows a unique kinase profile with selective inhibition of Janus Kinase-2 (JAK2; IC50=23 and 19 nM for JAK2(WT) and JAK2(V617F), respectively) within the JAK family (IC50=1280, 520 and 50 nM for JAK1, JK3 and TYK2, respectively) and fms-like tyrosine kinase-3 (FLT3; IC50=22 nM). SB1518 shows potent effects on cellular JAK/STAT pathways, inhibiting tyrosine phosphorylation on JAK2 (Y221) and downstream STATs. As a consequence SB1518 has potent anti-proliferative effects on myeloid and lymphoid cell lines driven by mutant or wild-type JAK2 or FLT3, resulting from cell cycle arrest and induction of apoptosis. SB1518 has favorable pharmacokinetic properties after oral dosing in mice, is well tolerated and significantly reduces splenomegaly and hepatomegaly in a JAK2(V617F)-driven disease model. SB1518 dose-dependently inhibits intra-tumor JAK2/STAT5 signaling, leading to tumor growth inhibition in a subcutaneous model generated with SET-2 cells derived from a JAK2(V617F) patient with megakaryoblastic leukemia. Moreover, SB1518 is active against primary erythroid progenitor cells sampled from patients with myeloproliferative disease. In summary, SB1518 has a unique profile and is efficacious and well tolerated in JAK2-dependent models. These favorable properties are now being confirmed in clinical studies in patients with myelofibrosis and lymphoma.


Assuntos
Antineoplásicos/uso terapêutico , Hidrocarbonetos Aromáticos com Pontes/uso terapêutico , Janus Quinase 2/antagonistas & inibidores , Leucemia Linfoide/tratamento farmacológico , Leucemia Mieloide/tratamento farmacológico , Pirimidinas/uso terapêutico , Antineoplásicos/farmacologia , Western Blotting , Hidrocarbonetos Aromáticos com Pontes/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Citometria de Fluxo , Humanos , Pirimidinas/farmacologia , Transdução de Sinais
20.
Cell Death Dis ; 1: e95, 2010 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-21368871

RESUMO

Human monocytes can be classified into two subsets with distinctive characteristics. In this study, we report a difference in apoptotic potential between these two subsets with CD14(+/low)CD16(+) monocytes being more susceptible than CD14(+)CD16(-) monocytes to undergo spontaneous apoptosis and apoptosis induced by reactive oxygen species (ROS). By global transcriptomic and proteomic approaches, we observed that CD14(+/low)CD16(+) monocytes expressed higher levels of pro-apoptotic genes and proteins such as TNFα, caspase 3, Bax and cytochrome c and showed more caspases 3 and 7 activities. They also exhibited greater aerobic respiration resulting in a higher production of ROS from the mitochondria. CD14(+)CD16(-) monocytes, in contrast, showed higher expression of glutathione (GSH)-metabolizing genes such as GSH peroxidase and microsomal GSH S-transferase and were more resistant to oxidative stress than CD14(+/low)CD16(+) monocytes. The apoptosis of CD14(+/low)CD16(+) monocytes was ROS dependent as reducing ROS levels significantly reduced cell death. This is the first report of a differential apoptotic propensity of human monocyte subsets, and gaining a better understanding of this process may help to provide a better understanding of the roles of these subsets during homeostasis and under pathological conditions, particularly in situations in which high levels of oxidants are present.


Assuntos
Apoptose , Receptores de Lipopolissacarídeos/metabolismo , Monócitos/classificação , Espécies Reativas de Oxigênio/metabolismo , Receptores de IgG/metabolismo , Caspase 3/metabolismo , Caspase 7/metabolismo , Citocromos c/metabolismo , Perfilação da Expressão Gênica , Glutationa Peroxidase/metabolismo , Glutationa Transferase/metabolismo , Humanos , Peróxido de Hidrogênio/farmacologia , Mitocôndrias/metabolismo , Monócitos/imunologia , Monócitos/metabolismo , Estresse Oxidativo , Proteoma/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Proteína X Associada a bcl-2/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA