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1.
Clin Appl Thromb Hemost ; 30: 10760296231223195, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38225166

RESUMO

Thrombophilia in venous thromboembolism (VTE) is multifactorial. Von Willebrand factor (vWF) plays a major role in primary hemostasis. While elevated vWF levels are well documented in VTE, findings related to its cleaving protease (ADAMTS-13) are contradicting. The aim of this study was to determine vWF, ADAMTS-13, and the multifactorial Thrombospondin-1 (TSP-1) protein levels in patients after 3-6 months following an unprovoked VTE episode. We also explored a possible association with factor V Leiden (FVL) mutation. vWF, ADAMTS-13 and TSP-1 were analyzed using ELISA kits in 60 VTE patients and 60 controls. Patients had higher levels of vWF antigen (P = .021), vWF collagen-binding activity (P = .008), and TSP-1 protein (P < .001) compared to controls. ADAMTS-13 antigen was lower in patients (P = .046) compared to controls but ADAMTS-13 activity was comparable between the two groups (P = .172). TSP-1 showed positive correlation with vWF antigen (rho = 0.303, P = .021) and negative correlation with ADAMTS-13 activity (rho = -0.244, P = .033) and ADAMTS-13 activity/vWF antigen ratio (rho = -0.348, P = .007). A significant association was found between the presence of FVL mutation and VTE (odds ratio (OR): 9.672 (95% confidence interval (CI) 2.074-45.091- P = .004), but no association was found between the mutation and the studied proteins (P > .05). There appears to be an imbalance between vWF and ADAMTS-13 in VTE patients even after 3-6 months following the onset of VTE. We report that the odds of developing VTE in carriers of FVL mutation are 9.672 times those without the mutation, but the presence of this mutation is not associated with the studied proteins.


Assuntos
Fator V , Trombofilia , Tromboembolia Venosa , Humanos , Proteína ADAMTS13/genética , Fator V/genética , Mutação , Trombospondina 1/genética , Tromboembolia Venosa/genética , Fator de von Willebrand/metabolismo
2.
Int J Lab Hematol ; 45(6): 945-952, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37438087

RESUMO

INTRODUCTION: Alterations in the endothelium and endothelial adhesion proteins such as von Willebrand factor (vWF) play major roles in hypercoagulability in thalassemia. vWF protein release leads to platelet aggregation and thrombi formation at the site of vascular injury. It is then degraded by the proteolytic enzyme ADAMTS13. Thrombospondin-1 is a multifactorial glycoprotein, which was reported to compete with ADAMTS13 for sites of vWF proteolysis. In this study, levels of vWF, ADAMTS13, and TSP-1 proteins were determined in ß-thalassemia major patients. A possible association between TSP-1 and vWF and ADAMTS-13 was also evaluated. METHODS: The study was conducted on 80 ß-thalassemia major patients and 80 age and sex matched healthy controls. The 80 patients were sub-divided into two groups; splenectomised and non-splenectomised. vWF, ADAMTS13 and TSP-1 plasma level were measured using ELISA technique. RESULTS: There was no significant difference in vWF and TSP-1 levels between patients and controls (p > 0.05). However, ADAMTS13 levels and ADAMTS13 activity/vWF antigen ratio were significantly higher in patients compared to controls (p < 0.05). VWF antigen and TSP-1 level were significantly higher in splenectomised patients (p = 0.025 and p < 0.001, respectively). We also observed a significant decrease in ADAMTS13 activity/vWF antigen ratio among splenectomised compared to non- splenectomised patients (p = 0.019). Correlation analysis showed a significant negative correlation between TSP-1 and vWF Collagen Binding Activity (r = -0.394, p = 0.021) and a positive correlation with ADAMTS13 activity/vWF antigen ratio (r = 0.356, p = 0.039) in splenectomised compared to non- splenectomised patients. CONCLUSION: Our findings highlight the adequacy of patient management protocols for ß-TM in Kuwait as patients presented with comparable levels of platelets, vWF and TSP-1 compared to normal controls. The reported increase in ADAMTS13 in patients may be required to maintain normal levels of vWF. Although no active thrombotic episodes were reported at the time of the study, the significant rise in platelets, vWF:Ag and TSP-1 levels in splenectomised patients may indicate a tendency towards hypercoagulability. Monitoring of splenectomised patients is recommended.


Assuntos
Trombofilia , Talassemia beta , Humanos , Proteína ADAMTS13 , Trombospondina 1/metabolismo , Fator de von Willebrand/análise
3.
Acta Haematol ; 144(2): 182-189, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32987383

RESUMO

BACKGROUND: Thrombospondin 1 (TSP-1) is a multifunctional glycoprotein secreted by platelets. In sickle cell disease (SCD), TSP-1 promotes red cell adhesion to the endothelium by binding to von Willebrand factor (vWF) and inhibiting its degradation by the protease ADAMTS-13. We investigated a possible correlation between TSP-1, vWF and ADAMTS-13 in adult and pediatric SCD patients. METHODS: Using commercially available ELISA kits, TSP-1, vWF and ADAMTS-13 levels were measured in 59 SCD patients (20 children and 39 adults) and compared with 59 age- and sex-matched controls. Associations between TSP-1 and parameters of interest were analyzed using Pearson's correlation coefficient. RESULTS: Although TSP-1 levels were higher in adult and pediatric SCD patients than in controls, the increase was not statistically significant (p > 0.05). We found a significant positive correlation between TSP-1 and platelet count in both adult (r = 0.402, p = 0.01) and pediatric (r = 0.589, p = 0.01) patients, which is expected due to increased platelet activation in SCD. There was a positive correlation between TSP-1 and vWF in normal adults (r = 0.305, p = 0.049) and children (r = 0.633, p = 0.005) but not in patients (p > 0.05). A significant negative correlation between TSP-1 and ADAMTS-13 activity (r = -0.41, p = 0.01) was found in adult patients. Also, a significant negative correlation between TSP-1 and ADAMTS-13/vWF antigen ratio in both normal controls (r = -0.595, p = 0.009) and patients (r = -0.493, p = 0.032) is reported for the pediatric group. CONCLUSIONS: Our findings confirm the inhibitory effects of TSP-1 on ADAMTS-13 activity in adult SCD patients. The negative correlation reported between TSP-1 and ADAMTS-13/vWF antigen ratio in pediatric subjects suggests a possible protective mechanism in younger individuals, although this is not related to the presence of SCD. This work emphasizes the impact of age on interpreting results related to the regulation of vWF expression and interaction with TSP-1 and ADAMTS-13 in SCD.


Assuntos
Proteína ADAMTS13/metabolismo , Anemia Falciforme/patologia , Trombospondina 1/metabolismo , Fator de von Willebrand/metabolismo , Proteína ADAMTS13/análise , Adulto , Anemia Falciforme/etnologia , Anemia Falciforme/genética , Árabes , Contagem de Células Sanguíneas , Estudos de Casos e Controles , Criança , Feminino , Hemólise , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Trombospondina 1/análise , Fator de von Willebrand/análise
4.
Saudi J Med Med Sci ; 5(1): 31-37, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-30787749

RESUMO

INTRODUCTION: Stigma and discrimination have been reported to cause unnecessary delay in mentally-ill patients seeking help, which adversely affects a patient's outcome. The attitude of health care professionals has been described as being, even more, negative than that of the general public, which worsens the prognosis for patients with a mental illness. AIMS: The aim of this study was to describe the attitude of nurses toward mentally-ill patients in a general hospital. METHODS: All the nurses in the hospital were administered a 40-item Community Attitudes Toward the Mentally-Ill (CAMI) questionnaire which determines whether the mentally-ill are viewed as "inferior;" deserve "sympathy;" perceived as a "threat" to society or "acceptable" if residing in community dwellings. The analysis of variance was performed to determine association of the four subscales with the individual characteristics, including age, gender, education, qualification type, position held, contact and contact type. RESULTS: Out of a total of 990 nurses, 308 (31%) completed the CAMI questionnaire. The mean scores for the authoritarian (2.85), benevolent (3.66), social restrictiveness (2.97) and community mental health ideology (3.48) subscales reflected a negative attitude of nurses toward mentally-ill patients. The direct or indirect utilization of the mental health facilities resulted in significantly higher authoritarian and lower benevolence scores, indicating a positive attitude change in this group of nurses. CONCLUSION: Despite the small size and selective nature of the sample, the nurses' negative attitude toward the mentally-ill patients provides useful baseline data for further large-scale studies and underscores the need for psychoeducation of different health care professionals, including nurses.

5.
J Thromb Thrombolysis ; 43(1): 117-123, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27613177

RESUMO

Sickle cell disease (SCD) is a severe form of hemolytic anemia characterized by chronic hemolysis and is associated with increased thrombotic risk. Elevated von Willebrand factor (vWF) levels in SCD have been attributed to increased secretion and impaired processing by its cleaving protease ADAMTS-13. In this study we measured vWF and ADAMTS-13 antigen and activity levels in our SCD patients. Hematological and biochemical parameters for 59 SCD patients (20 children and 39 adults) were analyzed and compared to 59 age- and sex-matched controls. Commercially available ELISA kits were used to measure vWF and ADAMTS-13 antigen and activity levels in patients and controls. Patients had significantly higher levels of vWF (p < 0.006) and ADAMTS-13 activity (p < 0.006) compared to controls. When patients were analyzed according to age and genotype, adult patients (23 SS and 16 Sß0thal) maintained higher vWF antigen levels (p < 0.001), but with reduced ADAMTS-13 activity to vWF:Ag ratio (p < 0.003) compared to controls. Pediatric patients (8 SS and 12 Sß0thal) had comparable vWF antigen levels to controls (p > 0.05), but had higher levels of ADAMTS-13 activity (p < 0.011) and ADAMTS-13 activity to vWF:Ag ratio (p < 0.038). Age is an important factor to consider when vWF and ADAMTS-13 proteins are analyzed among our patients. Increased vWF in adult patients may be attributed to increased production and resistance of vWF to proteolysis rather than ADAMTS-13 deficiency. This outcome was not seen in pediatric patients as higher ADAMTS-13 activity maintained vWF antigen at comparable levels to normal controls.


Assuntos
Proteína ADAMTS13/análise , Anemia Falciforme/sangue , Fator de von Willebrand/análise , Proteína ADAMTS13/imunologia , Proteína ADAMTS13/metabolismo , Adulto , Fatores Etários , Antígenos/sangue , Estudos de Casos e Controles , Criança , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Kuweit , Masculino , Fator de von Willebrand/imunologia , Fator de von Willebrand/metabolismo
7.
Forensic Sci Int Genet ; 7(4): e106-7, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23707636

RESUMO

Allele frequencies and population statistics of 15 forensically-important STR loci were estimated for seven populations residing in the State of Kuwait. The populations were: Saudi Arabian, Iraqi, Egyptian, Iranian, Sri Lankan, Bangladeshi, and Indian. All loci were highly polymorphic. After correction, only one locus in one population sample (Saudi Arabian) showed departure from Hardy-Weinberg equilibrium. The populations cluster (MDS Plot) generally with geographic distance and substructure effects for even these seven diverse populations is Fst<0.01.


Assuntos
Genética Forense , Genética Populacional , Repetições de Microssatélites/genética , Frequência do Gene , Humanos , Kuweit
8.
Scand J Clin Lab Invest ; 72(8): 614-8, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23020229

RESUMO

While von Willebrand factor (vWF) has been reported to be elevated in smokers, there are no reports on the effects of smoking on its cleaving protease ADAMTS-13, particularly in subjects of Arab ethnicity. This study was conducted to determine the effects of smoking on vWF and ADAMTS-13 antigen and activity levels in Arab males. Venous blood samples from 80 smoking (at rest) and 80 non-smoking healthy males were collected after asking subjects to fast and refrain from smoking for 8 hours. Similar sampling was done for 40 smokers (acute smokers), who were asked to smoke one cigarette immediately before blood collection. Plasma was used to measure ADAMTS-13 antigen and activity levels, as well as vWF antigen and collagen binding activity levels using commercial ELISA kits. Compared to non-smokers, ADAMTS-13 and vWF activities were significantly lower in smokers at rest (p < 0.05). Acute smokers had significantly higher levels of vWF activity and ADAMTS-13 antigen and activity levels (p < 0.01), compared to smokers at rest. Our results suggest that high vWF activity is accompanied by an increase in ADAMTS-13 activity as a natural physiological mechanism to degrade the elevated vWF molecules. If not followed by a subsequent smoke, the activities of both proteins subside. It is possible that the repeated increase in vWF and constant degradation by ADAMTS-13 results in lower overall levels of both proteins in smokers (at rest) compared to nonsmokers who do not experience a similar (repeated) injury to the endothelium.


Assuntos
Proteínas ADAM/sangue , Saúde , Fumar/sangue , Fator de von Willebrand/metabolismo , Proteína ADAMTS13 , Adolescente , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
9.
Forensic Sci Int ; 179(2-3): e31-6, 2008 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-18602779

RESUMO

The study presents a case of fatal poisoning with oleander leaves in an adult diabetic male. After repeated vomiting, and gastrointestinal distress the patient was admitted at the hospital with cardiac symptoms 1h after the ingestion. Urine samples were assayed immunochemically and by GC-MS for drugs of abuse and for general toxicological screen. Blood was analyzed for alcohol and volatiles by static head space GC-MS. Blood and oleander leaves were analyzed by LC-MS/MS for oleandrin and related compounds, the main cardiac glycosides of Nerium oleander. Oleandrin was detected by LC-MS/MS in the blood sample at a concentration of approximately 10 ng/ml. Another cardiac glycoside with pseudo-molecular ion of m/z 577, a likely structural isomer of oleandrin, was also detected in the blood and oleander leaves. However, by using the response as a function of concentration for oleandrin, this cardiac glycoside was roughly estimated at a concentration of approximately 10 ng/ml in the deceased blood. This would give a total fatal blood concentration of cardiac glycosides of about approximately 20 ng/ml in the deceased blood.


Assuntos
Cardenolídeos/intoxicação , Fitoterapia/efeitos adversos , Cardenolídeos/sangue , Diabetes Mellitus/tratamento farmacológico , Toxicologia Forense , Cromatografia Gasosa-Espectrometria de Massas , Parada Cardíaca/induzido quimicamente , Bloqueio Cardíaco/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Insuficiência de Múltiplos Órgãos/induzido quimicamente , Folhas de Planta/intoxicação , Fibrilação Ventricular/induzido quimicamente
10.
Med Princ Pract ; 17(2): 149-53, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18287800

RESUMO

OBJECTIVES: This study aimed at determining the effects of cigarette smoking based on gender, on several hematological parameters and von Willebrand factor protein in the asymptomatic Arab population of Kuwait. SUBJECTS AND METHODS: Ninety-two subjects participated in this study: 55 males (31 smokers and 24 nonsmokers) and 37 females (18 smokers and 19 nonsmokers). Complete blood count results were obtained using Beckman Coulter Hematology Analyzer. Von Willebrand factor functional activity was determined using an enzyme-linked immunoassay-based test in which anti-von Willebrand factor IgG monoclonal antibody was used that recognizes a functional epitope of the protein. The coagulation profile was obtained using ACL 9000 coagulation analyzer. RESULTS: Male smokers had significantly higher levels of white blood cell count (p = 0.03) and von Willebrand factor protein levels (p = 0.029), and a significantly shorter thrombin time (p = 0.019) than nonsmokers. Smoking did not appear to affect any of the parameters analyzed in females as no significant difference was found between smokers and nonsmokers (p > 0.05). CONCLUSION: Our results showed that smoking affected white blood cell count and von Willebrand factor levels in males and not in females, and as such could be potential markers for smoking-induced endothelial damage in asymptomatic Arab male smokers.


Assuntos
Árabes , Aterosclerose/prevenção & controle , Endotélio Vascular/lesões , Fumar/efeitos adversos , Fator de von Willebrand/metabolismo , Análise de Variância , Aterosclerose/sangue , Aterosclerose/etnologia , Aterosclerose/etiologia , Biomarcadores/sangue , Testes de Coagulação Sanguínea , Estudos de Casos e Controles , Diagnóstico Precoce , Feminino , Humanos , Kuweit , Contagem de Leucócitos , Modelos Lineares , Masculino , Fatores Sexuais , Fumar/sangue , Fumar/etnologia
11.
J Trop Pediatr ; 53(2): 93-7, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17166936

RESUMO

Iron deficiency anemia (IDA) and thalassemia minor are two of the most common causes of microcytic anemias worldwide. Because of similar red blood cell count parameters and blood picture, it was imperative to develop other measures that would differentially and correctly diagnose these two anemias. Several mathematical formulas and simple RBC indices have been introduced as simple, fast and inexpensive means of providing differential diagnosis for IDA and thalassemia minor. The Objective of this study was to apply and compare nine well-documented discriminant functions on a population of 153 confirmed cases of microcytic anemias (IDA n = 56, beta-thalassemia minor n = 47 and alpha-thalassemia n = 50) and to measure validity using Youden's Index. The results show that England and Fraser (E & F) Index had the highest Youden's Index value (98.2) in correctly differentiating between IDA and alpha- and beta-thalassemia minor, while Shine and Lal Index was found ineffective in differentiating between microcytic anemias in our population. E & F Index showed with great sensitivity and specificity to be the best discriminant function to differentiate between IDA and thalassemia minor cases.


Assuntos
Anemia Ferropriva/diagnóstico , Análise Discriminante , Talassemia beta/diagnóstico , Anemia Ferropriva/sangue , Diagnóstico Diferencial , Humanos , Sensibilidade e Especificidade , Talassemia beta/sangue
12.
Med Princ Pract ; 14(4): 241-4, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15961933

RESUMO

OBJECTIVES: To compare the performance of SEDIsystem(TM), a fully automated analyzer for the measurement of the erythrocyte sedimentation rate (ESR), with the manual Westergren method. MATERIALS AND METHODS: Both methods were applied to 150 randomly selected subjects. The linear regression and Bland and Altman data analysis methods were used to measure the agreement between the automated and manual methods. RESULTS: The regression analysis showed a good correlation between the two methods (r=0.91). The Bland and Altman data analysis showed no systematic bias (95% confidence interval for mean difference); however, limits of agreement were between 11.52 and -37.88. This indicates that ESR values measured by the SEDIsystem may be 11.52 mm/h above or 37.88 mm/h below the reference method. A greater scatter of data was also observed with abnormally high (>25 mm/h) ESR results (mean of difference=-21.4 and limits of agreement=-45.2 and 2.26) compared with normal (<25 mm/h) readings (mean of difference=-3.9 and limits of agreement=-13.5 and 5.7). CONCLUSION: The Bland and Altman statistical analysis showed a wide degree of scatter between results obtained by the two ESR techniques that was not clearly demonstrated using the linear regression analysis. The automated system was found to underestimate ESR with the Bland and Altman statistical analysis, and therefore a correction factor is recommended.


Assuntos
Autoanálise , Sedimentação Sanguínea , Testes Diagnósticos de Rotina/instrumentação , Testes Diagnósticos de Rotina/métodos , Interpretação Estatística de Dados , Humanos , Kuweit , Laboratórios Hospitalares , Modelos Lineares
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