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1.
Biomech Model Mechanobiol ; 20(5): 1871-1887, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34191187

RESUMO

In the present study, the effect of physical and operational uncertainties on the hydrodynamic and hemocompatibility characteristics of a centrifugal blood pump designed by the U.S. food and drug administration is investigated. Physical uncertainties include the randomness in the blood density and viscosity, while the operational uncertainties are composed of the pump rotational speed, mass flow rate, and turbulence intensity. The non-intrusive polynomial chaos expansion has been employed to conduct the uncertainty quantification analysis. Additionally, to assess each stochastic parameter's influence on the quantities of interest, the sensitivity analysis is utilized through the Sobol' indices. For numerical simulation of the pump's blood flow, the SST [Formula: see text] turbulence model and a power-law model of hemolysis were employed. The pump's velocity field is profoundly affected by the rotational speed in the bladed regions and the mass flow rate in other zones. Furthermore, the hemolysis index is dominantly sensitive to blood viscosity. According to the results, pump hydraulic characteristics (i.e., head and efficiency) show a more robust behavior than the hemocompatibility characteristics (i.e., hemolysis index) regarding the operational and physical uncertainties. Finally, it was found that the probability distribution function of the hemolysis index covers the experimental measurements.


Assuntos
Doenças Cardiovasculares/terapia , Coração Auxiliar , Modelos Cardiovasculares , Benchmarking , Viscosidade Sanguínea , Simulação por Computador , Desenho de Equipamento , Hemodinâmica , Hemólise , Humanos , Hidrodinâmica , Modelos Teóricos , Dinâmica não Linear , Probabilidade , Processos Estocásticos , Estados Unidos , United States Food and Drug Administration , Viscosidade
2.
J Arthropod Borne Dis ; 12(3): 252-261, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30584548

RESUMO

BACKGROUND: Since ticks are potent vectors of various diseases, identification of these species are clinically important to protect the public health and control veterinary problems in the communities. We aimed to figure out the frequency of ticks on cows, goats, sheep, lambs, turtles and also obscure hosts in Kurdistan Province, bordered with Iraq June 2012 to May 2013. METHODS: The hosts were selected randomly and examined individually for tick infestation. In case of infestation, ticks were collected using forceps and then preserved in 70% ethyl alcohol. All collected specimens were preserved in tubes and relative information was recorded and then identified based on morphological characteristics. RESULTS: Totally, 1209 ticks were collected. The prevalence of ticks on cows, sheep, goats, lambs, turtles, poultry and obscure hosts was 11.33%, 55.41%, 6.53%, 5.95%, 0.9%, 8.02% and 11.82% respectively. The mean number of ticks on each animal was 1.6. Number of 5 genera, including Rhipicephalus, Argas, Ornithodoros, Hyalomma and Haemaphysalis and 9 species; including R. sanguineus (60.05%), R. bursa (0.08), Hy. anatolicum (12.33), Hy. asiaticum (1.49), Hy. aegyptium (0.91), Hy. marginatum (0.08), Haemaphysalis parva (4.22), Hyalomma sp. (0.99), Ornithodoros lahorensis (11.83), and Argas persicus (8.02) were identified. CONCLUSION: The most abundant species in this study area was Rh. sanguineus (60.05%). Due to high prevalence of tick specimens and a variety of collected species from sheep (55.41%), the vaccination of sheep and control of tick vectors are recommended.

3.
Jundishapur J Microbiol ; 8(3): e16873, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25861432

RESUMO

BACKGROUND: Chronic hepatitis B virus (HBV) infection has a broad spectrum of manifestation, ranging from silent carrier state to advanced cirrhosis and hepatocellular carcinoma. The persistence of HBV DNA in serum and hepatocytes of the cirrhotic patient could be detected by molecular techniques in spite of negative HBV serologic markers. OBJECTIVES: This case-control study was designed to evaluate the prevalence of occult HBV infection (OBI) in patients with cryptogenic liver cirrhosis in comparison with healthy subjects. PATIENTS AND METHODS: Of 165 patients with liver cirrhosis, 50 consecutive patients with cryptogenic cirrhosis and 80 healthy individual without any risk factors as a control group were enrolled in this study. Their sera were tested for HBV DNA using nested PCR method. RESULTS: Of 50 patients with cryptogenic cirrhotic, 36 (72%) were male. The mean age of patients was 53.34 ± 14.73 years; 80 healthy subjects were selected as control group with mean age of 32.65 ± 8.51 years; 7 (14%) of the patients with cryptogenic cirrhosis showed positive HBV DNA by PCR, while HBV DNA was negative for the control group (P = 0.0001); 4 (57%) cases with positive HBV shown by PCR were negative for anti-HBc and anti-HBs tests. The mean level of transaminases was significantly higher in patients with cirrhosis. There were no significant differences in demographic parameters, transaminases level and degree of hepatic failure among cirrhotic patients with and without OBI. CONCLUSIONS: The prevalence of OBI was relatively high in patients with cryptogenic cirrhosis. OBI was found among the patients above 40 years old. Prospective cohort studies are needed to evaluate the clinical significance of OBI.

4.
Iran J Pediatr ; 24(2): 131-9, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25535530

RESUMO

OBJECTIVE: The surveillance of acute flaccid paralysis (AFP) is a key strategy for monitoring the progress of poliomyelitis eradication and is a sensitive measure for detecting potential cases of poliomyelitis and poliovirus infection. This study was conducted to describe the characteristics of patients reported with AFP, and to evaluate the performance of the surveillance system in Kurdistan province, western Iran, using indicators recommended by the World Health Organization (WHO). METHODS: This observational study was conducted from January 2000 to December 2010 at the Kurdistan Center for Disease Control and the Department of Pediatrics. All children who fulfilled the WHO definition for AFP were included in our study. The stool samples of all the children were sent for poliovirus isolation. All the patients were evaluated for 60 days after the onset of symptoms to identify the signs of residual weakness. FINDINGS: One-hundred thirty nine children aged <15 years were reported to the Center for Diseases Control with AFP. In 138 (99%) stool samples no poliovirus was isolated. None of the patients was diagnosed as having acute poliomyelitis or polio-compatible paralysis. Guillain-Barré syndrome was the most frequent final diagnosis (79 cases) followed by Transverse Myelitis (7 cases) and Encephalitis (6 cases). By detecting 1.3 to 3.6 (mean 3.2) AFP cases per 100 000 population in Kurdistan during the study period, we achieved the WHO target for AFP surveillance. All performance indicators but one consistently met the WHO requirements and therefore demonstrated the effectiveness of the AFP surveillance program in Kurdistan. CONCLUSION: The effective surveillance system in Kurdistan and its evaluation may serve as a model for the surveillance of other infectious diseases.

5.
Immunol Res ; 51(2-3): 153-60, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22105838

RESUMO

Immunotherapy with dendritic cells (DCs), which have been manipulated ex vivo to become immunogenic or tolerogenic, has been tested in clinical trials for disease therapy. DCs are sentinels of the immune system, which after exposure to antigenic or inflammatory signals and crosstalk with effector CD4(+) T cells express high levels of costimulatory molecules and cytokines. Upregulation of either costimulatory molecules or cytokines promotes immunologic DCs, whereas their downregulation generates tolerogenic DCs (TDCs), which induce T regulatory cells (Tregs) and a state of tolerance. Immunogenic DCs are used for the therapy of infectious diseases such as HIV-1 and cancer, whereas tolerogenic DCs are used in treating various autoimmune diseases and in transplantation. DC vaccination is still at an early stage, and improvements are mainly needed in quality control of monitoring assays to generate clinical-grade DC products and to assess the effect of DC vaccination in future clinical trials. Here, we review the recent work in DC generation and monitoring approaches for DC-based trials with immunogenic or tolerogenic DCs.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Separação Celular/métodos , Células Dendríticas/imunologia , Células Dendríticas/transplante , Imunoterapia/métodos , Antígenos CD19/metabolismo , Doenças Autoimunes/terapia , Comunicação Celular , Técnicas de Cultura de Células , Diferenciação Celular , Proliferação de Células , Humanos , Tolerância Imunológica , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Ativação Linfocitária , Neoplasias/terapia
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