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1.
Bone Marrow Transplant ; 56(3): 614-621, 2021 03.
Article in English | MEDLINE | ID: mdl-33009514

ABSTRACT

Patients with acute myeloid leukaemia (AML) who lack a matched sibling or unrelated donor commonly undergo transplantation from a donor matched at 9/10 HLA-A, -B, -C, -DRB1, -DQB1 alleles, and it is unclear if a specific locus mismatch is preferable to any other. We therefore studied 937 patients with AML in complete remission transplanted using a reduced intensity conditioning regimen from an unrelated donor mismatched at a single allele. In a multivariate analysis, patient age, adverse karyotype and patient cytomegalovirus (CMV) seropositivity were correlated with decreased leukaemia free survival (LFS) and overall survival (OS). There was no significant difference in LFS or OS between patients transplanted from donors mismatched at HLA-A, -B, -C or -DRB1 in comparison to a HLA-DQB1 mismatched transplant. In a multivariate analysis, patients transplanted with a HLA-A mismatched donor had higher rates of acute graft-versus-host disease (GVHD) and non-relapse mortality (NRM) than patients transplanted with a HLA-DQB1 mismatched donor. Patient CMV seropositivity was associated with an increase in NRM and acute GVHD and reduced LFS and OS, regardless of donor CMV status. For CMV seropositive patients lacking a fully matched donor, alternative GVHD and CMV prophylaxis strategies should be considered.


Subject(s)
Graft vs Host Disease , Hematopoietic Stem Cell Transplantation , Leukemia, Myeloid, Acute , Humans , Leukemia, Myeloid, Acute/therapy , Neoplasm Recurrence, Local , Retrospective Studies , Unrelated Donors
2.
Syst Rev ; 9(1): 285, 2020 12 07.
Article in English | MEDLINE | ID: mdl-33287892

ABSTRACT

BACKGROUND: FMS-like tyrosine kinase 3 (FLT3) is the most frequent mutation in AML. With two FLT3 inhibitors recently approved by the FDA (midostaurin and gilteritinib), there is a need to evaluate these targeted agents. PURPOSE: To assess the clinical effectiveness of FLT3 inhibitors in AML patients. METHODS: Standard systematic review methods were utilised. Searches were conducted to July 2020 for completed and in-progress randomised controlled trials of FLT3 inhibitors in AML. A fixed-effect meta-analysis was undertaken. RESULTS: Eight completed trials involving 2656 patients and assessing five different FLT3 inhibitors (sorafenib, lestaurtinib, midostaurin, gilteritinib and quizartinib) were included. The pooled results were as follows (FLT3 inhibitor/control): overall survival hazard ratio (HR) = 0.83 (95% confidence interval [CI] 0.75 to 0.92, p = 0.0005), event-free survival HR = 0.85 (95% CI 0.77 to 0.94, p = 0.002), relapse-free survival HR = 0.76 (95% CI 0.64 to 0.90, p = 0.001), complete remission relative risk (RR) = 1.11 (95% CI 1.00 to 1.22. p = 0.05) and 60-day mortality RR = 1.04 (95% CI 0.77 to 1.40, p = 0.79). Relative risk of grade 3 and above vascular, dermatological, respiratory and hepatobiliary adverse events were found to be statistically significantly higher in the FLT3 inhibitor group compared to control, but the actual numbers of events were relatively small. Nineteen ongoing trials are still in progress, only one of which specifically targets older patients with AML. CONCLUSIONS: There is evidence to support the use of FLT3 inhibitors in patients with AML, but more data is needed to verify the optimum use of the drugs regarding type of inhibitor, disease stage and patient characteristics, not only in relation to disease control, but adverse events and quality of life. There are a large number of ongoing trials; therefore, the results of this review are not a fait accompli; thus, is it recommended that the review be updated in a couple of years' time. Given the challenges in extracting the complete data set required to assess clinical effectiveness, it is highly recommended that ongoing and future trials improve transparency and consistency of reporting of all trial outcomes, particularly disease control and adverse events, to enable a global clinical effectiveness assessment. SYSTEMATIC REVIEW REGISTRATION: PROSPERO CRD42017055581.


Subject(s)
Leukemia, Myeloid, Acute , fms-Like Tyrosine Kinase 3 , Humans , Leukemia, Myeloid, Acute/drug therapy , Neoplasm Recurrence, Local , Quality of Life , Treatment Outcome , fms-Like Tyrosine Kinase 3/genetics
3.
Clin Genet ; 93(2): 412-416, 2018 02.
Article in English | MEDLINE | ID: mdl-29095481

ABSTRACT

Filamin B (FLNB) functions as a switch that can affect chrondrocyte development and endochondral bone formation through a series of signaling molecules and transcription factors that also affect Sertoli cell development. Here, we report a subject with a novel skeletal dysplasia and co-existing 46,XY gonadal dysgenesis and biallelic mutations in FLNB. Whole exome sequencing was performed to identify mutations. Quantitative polymerase chain reaction (qPCR) and flow variant assays were performed to quantify RNA, proteins and phosphorylated proteins. The TOPFLASH reporter was performed to quantify ß-catenin activity. Mutations were identified in the FLNB gene (FLNB:p.F964L, FLNB:p.A1577V). These mutations increased binding of FLNB protein to the MAP3K1 and RAC1 signal transduction complex and activated ß-catenin and had different effects on phosphorylation of MAP kinase pathway intermediates and SOX9 expression. Direct activation of ß-catenin through the FLNB-MAP3K1-RAC1 complex by FLNB mutations is a novel mechanism for causing 46,XY gonadal dysgenesis. The mechanism of action varies from those reported previously for loss of function mutations in SOX9 and gain-of-function mutations in MAP3K1.


Subject(s)
Filamins/genetics , Gonadal Dysgenesis, 46,XY/genetics , Musculoskeletal Abnormalities/genetics , Osteochondrodysplasias/genetics , beta Catenin/genetics , Gain of Function Mutation/genetics , Gonadal Dysgenesis, 46,XY/complications , Gonadal Dysgenesis, 46,XY/physiopathology , Humans , Infant, Newborn , MAP Kinase Kinase Kinase 1/genetics , Male , Multiprotein Complexes/genetics , Musculoskeletal Abnormalities/complications , Musculoskeletal Abnormalities/physiopathology , Mutation , Osteochondrodysplasias/complications , Osteochondrodysplasias/physiopathology , SOX9 Transcription Factor/genetics , rac1 GTP-Binding Protein/genetics
5.
Ann Hematol ; 94(3): 361-73, 2015 Mar.
Article in English | MEDLINE | ID: mdl-25284166

ABSTRACT

Conventional chemotherapy is ineffective in the majority of patients with acute myeloid leukaemia (AML), and monoclonal antibodies recognising CD33 expressed on myeloid progenitors (e.g. gemtuzumab ozogamicin (GO)) have been reported to improve outcome in patients with AML. Reports of excess toxicity have resulted in GO's licence being withdrawn. As a result, the role of these agents remains unclear. A systematic review and meta-analysis included studies of patients with AML who had entered a randomised control trial (RCT), where one arm included anti-CD33 antibody therapy. Fixed effect meta-analysis was used, involving calculation of observed minus expected number of events, and variance for each endpoint in each trial, with the overall treatment effect expressed as Peto's odds ratio with 95 % confidence interval. Meta-analysis of 11 RCTs with 13 randomisations involving GO was undertaken. Although GO increased induction deaths (p = 0.02), it led to a reduction in resistant disease (p = 0.0009); hence, there was no improvement in complete remission. Whilst GO improved relapse-free survival (hazard ratio (HR) = 0.90, 95 % confidence interval (CI) = 0.84-0.98, p = 0.01), there was no overall benefit of GO in overall survival (OS) (HR = 0.96, 95 % CI = 0.90-1.02, p = 0.2). GO improved OS in patients with favourable cytogenetics, with no evidence of benefit in patients with intermediate or adverse cytogenetics (test for heterogeneity between subtotals p = 0.01). GO has a potent clinically detectable anti-leukaemic effect. Further trials to investigate its optimum delivery and identification of patient populations who may benefit are needed.


Subject(s)
Aminoglycosides/therapeutic use , Antibodies, Monoclonal, Humanized/therapeutic use , Antineoplastic Agents/therapeutic use , Leukemia, Myeloid, Acute/drug therapy , Gemtuzumab , Humans , Randomized Controlled Trials as Topic , Sialic Acid Binding Ig-like Lectin 3/antagonists & inhibitors , Sialic Acid Binding Ig-like Lectin 3/immunology
6.
Anal Bioanal Chem ; 406(17): 4173-81, 2014 Jul.
Article in English | MEDLINE | ID: mdl-24752694

ABSTRACT

Fingerprint evidence offers great value to criminal investigations since it is an internationally recognized and established means of human identification. With recent advances in modern technology, scientists have started analyzing not only the ridge patterns of fingerprints but also substances which can be found within them. The aim of this work was to determine whether Fourier transform infrared (FTIR) spectromicroscopy could be used to detect contamination in a fingerprint which was dusted with powder (a technique already recognized as an effective and reliable method for developing latent fingerprints) and subsequently lifted off with adhesive tape. Explosive materials (pentaerythritol tetranitrate, C-4, TNT) and noncontrolled substances (sugar, aspirin) were used to prepare contaminated fingerprints on various substrates. Freshly deposited fingermarks with powders which were lifted off with adhesive tapes (provided by Singapore Police Force) were analyzed using a Bruker Hyperion 2000 microscope at the ISMI beamline (Singapore Synchrotron Light Source) with an attenuated total reflection objective. FTIR spectroscopy is a nondestructive technique which requires almost no sample preparation. Further, the fingerprint under analysis remains in pristine condition, allowing subsequent analysis if necessary. All analyzed substances were successfully distinguished using their FTIR spectra in powdered and lifted fingerprints. This method has the potential to significantly impact forensic science by greatly enhancing the information that can be obtained from the study of fingerprints.

8.
Analyst ; 137(15): 3459-65, 2012 Aug 07.
Article in English | MEDLINE | ID: mdl-22693711

ABSTRACT

Synchrotron radiation-based Fourier transform infra-red (SR-FTIR) micro-imaging has been developed as a rapid, direct and non-destructive technique. This method, taking advantage of the high brightness and small effective source size of synchrotron light, is capable of exploring the molecular chemistry within the microstructures of microscopic particles without their destruction at high spatial resolutions. This is in contrast to traditional "wet" chemical methods, which, during processing for analysis, often caused destruction of the original samples. In the present study, we demonstrate the potential of SR-FTIR micro-imaging as an effective way to accurately identify microscopic particles deposited within latent fingerprints. These particles are present from residual amounts of materials left on a person's fingers after handling such materials. Fingerprints contaminated with various types of powders, creams, medications and high explosive materials (3-nitrooxy-2,2-bis(nitrooxymethyl)propyl nitrate (PETN), 1,3,5-trinitro-1,3,5-triazinane (RDX), 2-methyl-1,3,5-trinitrobenzene (TNT)) deposited on various - daily used - substrates have been analysed herein without any further sample preparation. A non-destructive method for the transfer of contaminated fingerprints from hard-to-reach areas of the substrates to the place of analysis is also presented. This method could have a significant impact on forensic science and could dramatically enhance the amount of information that can be obtained from the study of fingerprints.


Subject(s)
Aspirin/analysis , Dermatoglyphics , Explosive Agents/analysis , Powders/analysis , Spectroscopy, Fourier Transform Infrared , Synchrotrons , Carbohydrates/analysis , Humans , Particle Size , Triazines/analysis , Trinitrotoluene/analysis
9.
Clin Genet ; 81(3): 272-7, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22171599

ABSTRACT

DNA sequencing of candidate genes or whole exomes on a diagnostic or investigational basis will yield a plethora of variants of uncertain significance whose potential phenotypic roles cannot be readily demonstrated by prediction programs, SNP databases nor conventional genetic analysis. Many variants may produce phenotypic changes in the encoded proteins by affecting the quantity, post-translational modification or protein interactions. Here, we establish the application of the method of flow cytometry following immunoprecipitation to show that known protein interactions are altered in the B-lymphoblastoid cells of patients with 46,XY gonadal dysgenesis arising from mutations in the MAP3K1 gene. This method can be scaled readily to test multiple interactions for many variants simultaneously from available tissues as well as quantify the effects of variants on protein accumulation and post-translational modification, thus providing an efficient means for screening variants of uncertain significance for phenotypic effects.


Subject(s)
Genetic Association Studies , Genetic Testing/methods , Genetic Variation , Gonadal Dysgenesis/genetics , MAP Kinase Kinase Kinase 1/genetics , Cells, Cultured , Flow Cytometry/methods , Humans , Immunoprecipitation/methods , Male , Phenotype , Polymorphism, Single Nucleotide , Sequence Analysis, DNA
11.
J Nurs Manag ; 9(4): 191-204, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11472508

ABSTRACT

BACKGROUND: Research in the west has shown that job satisfaction, productivity and organizational commitment are affected by leadership behaviours. The purpose of this study is to determine the effect of leadership behaviours on employee outcomes in Singapore. Very little research related to this subject has been done in health care settings in this country. The comparison of the results of the different types of settings and samples will allow a better understanding of the relationship between leadership behaviours and employee outcomes and thus help to determine if leadership is worth the extra effort. METHOD: The study explored the relationships between five leadership behaviours identified by Kouzes and Posner and the employee outcomes of registered nurses practising in the general wards, intensive care units and the coronary care unit in an acute hospital. Survey questionnaires were used to elicit responses from 100 registered nurses and 20 managers belonging to the organization. Data collected included demographic characteristics and the degree to which the five types of leadership behaviours were used as perceived by the nurse managers and the registered nurses. In addition, the level of nurse job satisfaction, the degree of productivity and the extent of organizational commitment are described. FINDINGS: The findings show a similar trend to the original studies in the United States of America. Use of leadership behaviours and employee outcomes were significantly correlated. The regression results indicate that 29% of job satisfaction, 22% of organizational commitment and 9% of productivity were explained by the use of leadership behaviours. Recommendations are made in the light of these findings.


Subject(s)
Attitude of Health Personnel , Job Description , Leadership , Nurse Administrators/organization & administration , Nurse Administrators/psychology , Nursing Staff, Hospital/psychology , Nursing, Supervisory/organization & administration , Professional Competence/standards , Adolescent , Adult , Efficiency , Female , Humans , Job Satisfaction , Male , Middle Aged , Models, Nursing , Motivation , Nurse Administrators/education , Nurse's Role , Nursing Administration Research , Personnel Loyalty , Regression Analysis , Singapore , Surveys and Questionnaires
12.
J Pharmacol Exp Ther ; 288(1): 148-56, 1999 Jan.
Article in English | MEDLINE | ID: mdl-9862765

ABSTRACT

In the dog saphenous vein (DSV), phenylephrine (PE) responses through alpha-1 adrenoceptors receptors are antagonized by both alpha-1 and alpha-2 receptor antagonists. Furthermore, pretreatment with chloroethylclonidine (CEC) eliminates prazosin binding but reduces rauwolscine binding by half (). In new functional experiments, the effects of preincubation with phenoxybenzamine (PBZ), an irreversible alpha adrenoceptor antagonist, on responses to PE and two selective alpha-2 adrenoceptor agonists were evaluated. Also, the ability of prazosin or rauwolscine to prevent irreversible losses of responses to these agonists when coincubated with PBZ was determined. Preincubation in PBZ (10-300 nM) concentration dependently reduced PE Emax and the calculated fraction of residual receptors (q). Preincubation in PBZ (10-300 nM) increased KB values for prazosin (30 and 100 nM) but did not alter the KB value for rauwolscine (50 nM) acting at the residual receptors from control values. Coincubation of PBZ with prazosin partially prevented these PBZ actions (Emax partly restored) on responses to PE, but coincubation of rauwolscine (/=300 nM caused >50% reduction in Emax values of responses but did not alter the EC50 values for either agonist. Coincubation of rauwolscine with PBZ protected responses to alpha-2 agonists against PBZ (1 microM) effects. This study shows that PE initiates contractions at atypical alpha-1 adrenoceptors represented by all sites of PE action. Rauwolscine antagonizes PE actions but does not protect against PBZ inactivation. Typical alpha-2 adrenoceptors are distinguished from the unusual alpha-1 adrenoceptors by their lesser sensitivity to PBZ and their protection by rauwolscine from PBZ.


Subject(s)
Adrenergic alpha-Antagonists/pharmacology , Phenoxybenzamine/pharmacology , Receptors, Adrenergic, alpha/metabolism , Saphenous Vein/metabolism , Adrenergic alpha-Agonists/pharmacology , Alkylating Agents/pharmacology , Alkylation/drug effects , Animals , Azepines/pharmacology , Binding, Competitive/drug effects , Brimonidine Tartrate , Dogs , Dose-Response Relationship, Drug , Drug Interactions , Phenylephrine/metabolism , Prazosin/pharmacology , Quinoxalines/pharmacology , Receptors, Adrenergic, alpha/classification , Receptors, Adrenergic, alpha-2/metabolism , Saphenous Vein/drug effects , Yohimbine/pharmacology
14.
Anesthesiology ; 88(3): 589-600, 1998 Mar.
Article in English | MEDLINE | ID: mdl-9523800

ABSTRACT

BACKGROUND: Phenotyping malignant hyperthermia (MH) by contracture testing has a low but quantifiable degree of inaccuracy, measured by its sensitivity and specificity. Quantifying the limitations inherent in diagnostic testing for MH can help resolve issues in clinical practice, such as the interpretation of a negative test and the apparent lack of complete genetic linkage to RYR1. METHODS: Bayesian models, mathematical descriptions of the outcome of diagnostic testing, were constructed. The inputs to the model include patient factors, summarized in a single number called pretest probability (PTP), and sensitivity and specificity that specify the accuracy of the entire test process. The outputs of the model include positive predictive value (PPV) and negative predictive value (NPV), which are numeric expressions of diagnostic certainty of positive and negative test results. A special case was constructed for equivocal results. RESULTS: The PPV, NPV, and efficiency of contracture testing for MH are functions of PTP, sensitivity, and specificity. The NPV is high for all clinical PTP, whereas PPV is clinically useful for moderate to high PTP. CONCLUSIONS: Diagnostic contracture testing for MH is clinically useful because of high NPV and can exclude MH with near certainty. For MH probands, the clinical grading scale for MH may guide PTP estimation, whereas for relatives of probands, PTP is a function of kinship to a known MH-susceptible relative. A sequential testing strategy optimizes diagnostic information by maximizing PTP within a pedigree. Incomplete testing of parents of an MH susceptible child can pose a significant risk of false-negative results for the untested parent. Even with optimal pedigree testing strategies, the PPV drift effect results in a considerable source of phenotypic uncertainty for genetic linkage studies.


Subject(s)
Contracture/chemically induced , Malignant Hyperthermia/diagnosis , Bayes Theorem , Biopsy , Chromosomes, Human, Pair 19 , Humans , Malignant Hyperthermia/physiopathology , Muscles/physiopathology
15.
Br J Pharmacol ; 112(2): 604-10, 1994 Jun.
Article in English | MEDLINE | ID: mdl-7521261

ABSTRACT

1. In the rat and guinea-pig aorta, we observed that the contraction to hypertonically-added K+, unlike the isotonic K(+)-induced contraction, was only partially sensitive to nicardipine (0.1, 1 and 10 microM), an L-type Ca2+ channel blocker and occurred in Ca(2+)-free medium containing 50 microM EGTA. We have characterized this nicardipine-insensitive hypertonically-added K+ contraction. 2. The contraction induced by an equi-osmolar concentration of mannitol was similar in size to that evoked by hypertonically-added K+. 3. When the tissue was depleted of its internal Ca2+ stores with various agents such as phenylephrine (10 microM) cyclopiazonic acid (30 microM), thapsigargin (1 microM) or ryanodine (30 microM), or by incubation in Ca(2+)-free medium over 30 min, little effect was observed on the high K+ contracture in the presence of L-type Ca2+ channel blockade. 4. Phentolamine (10 microM) or indomethacin (10 microM) did not reduce the contraction induced by high K+. 5. Application of a protein kinase C inhibitor, H7 (10, 30 and 100 microM) or calphostin C (1 microM), reduced the high K+ contraction but not that caused by an equi-osmolar concentration of mannitol. 6. The data suggest that hypertonic K(+)-induced contraction differs from that caused by hypertonicity or depolarization per se and invokes membrane enzyme activation.


Subject(s)
Muscle, Smooth, Vascular/drug effects , Naphthalenes , Nicardipine/pharmacology , Potassium Chloride/pharmacology , Protein Kinase C/antagonists & inhibitors , 1-(5-Isoquinolinesulfonyl)-2-Methylpiperazine , Animals , Aorta, Thoracic/drug effects , Calcium/metabolism , Guinea Pigs , Hypertonic Solutions , In Vitro Techniques , Indomethacin/pharmacology , Isoquinolines/pharmacology , Male , Mannitol/pharmacology , Muscle Contraction/drug effects , Phentolamine/pharmacology , Piperazines/pharmacology , Polycyclic Compounds/pharmacology , Rats , Rats, Wistar
16.
Cleve Clin J Med ; 60(4): 325-9, 1993.
Article in English | MEDLINE | ID: mdl-8339457

ABSTRACT

The number of people smoking free-base cocaine, or "crack," has increased dramatically in recent years. Concomitantly, the literature describing complications of such use has grown as well. Adverse pulmonary effects are being increasingly noted, such as respiratory symptoms, pulmonary hemorrhage, pulmonary edema, asthma, and pulmonary barotrauma. These and other pulmonary effects are reviewed.


Subject(s)
Crack Cocaine/adverse effects , Lung Diseases/chemically induced , Respiratory Tract Diseases/chemically induced , Humans , Substance-Related Disorders/complications
19.
Conn Med ; 56(4): 179-83, 1992 Apr.
Article in English | MEDLINE | ID: mdl-1606816

ABSTRACT

Lung function tests were performed on 49 fire fighters of the city of New Haven. Their mean age was 36.4 years, with a mean of 11.7 years as fire fighters. The lung function tests were compared to a control group with a mean age of 33.4 years. There was no significant difference between the mean normal pulmonary function tests of the fire fighters and the control group. The results showed that in this group of fire fighters long-term occupational exposure was not associated with pulmonary function abnormalities.


Subject(s)
Fires , Lung/physiology , Occupational Health , Adolescent , Adult , Connecticut , Forced Expiratory Volume , Humans , Middle Aged , Vital Capacity
20.
Eur Respir J Suppl ; 7: 663s-665s, 1989 Jul.
Article in English | MEDLINE | ID: mdl-2508653

ABSTRACT

Malnutrition is fairly common in patients with chronic obstructive pulmonary disease, the more severe the airway obstruction the more severe the nutritional status. The consequences of nutritional depletion on respiratory and immune systems are ventilatory compromise and susceptibility to infection. Diaphragm muscle mass and thickness is decreased in patients with COPD. This results in decreased maximum voluntary ventilation and diminished inspiratory pressure. Malnutrition is one of the causes of failure to wean in patients with respiratory failure. Malnutrition also has profound effects on cell-mediated immune response and humoral immunity with reduced levels of secretory IgA. In patients with COPD, colonization of respiratory tract bears a direct relationship with parameters of nutritional status. Patients with significant nutritional impairment have more tracheal cell bacteria adhered to and the tracheas were more frequently colonized by Pseudomonas species. The improvement of nutrition in these patients resulted in less bacterial cell binding to tracheal epithelial cells.


Subject(s)
Enteral Nutrition , Lung Diseases, Obstructive/complications , Nutrition Disorders/therapy , Humans , Lung Diseases, Obstructive/immunology , Lung Diseases, Obstructive/physiopathology , Nutrition Disorders/etiology , Nutrition Disorders/immunology
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