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1.
In December 2019, a new type of coronavirus was detected for the first time in Wuhan, Hubei Province, China. According to the reported data, the emerging coronavirus has spread worldwide, infecting more than fifty-seven million individuals, leading to more than one million deaths. The current study aimed to review and discuss the hematological findings of COVID-19. Laboratory changes and hematologic abnormalities have been reported repeatedly in COVID-19 patients. WBC count and peripheral blood lymphocytes are normal or slightly reduced while these indicators may change with the progression of the disease. In addition, several studies demonstrated that decreased hemoglobin levels in COVID-19 patients were associated with the severity of the disease. Moreover, thrombocytopenia, which is reported in 5%-40% of patients, is known to be associated with poor prognosis of the disease. COVID-19 can present with various hematologic manifestations. In this regard, accurate evaluation of laboratory indicators at the beginning and during COVID-19 can help physicians to adjust appropriate treatment and provide special and prompt care for those in need.  相似文献   
2.
The immunoregulatory cytokine, interleukin-10 (IL-10), has been shown to inhibit the maturation of human myeloid dendritic cells (DC). In the present study, we demonstrate that IL-10 has paradoxical effects on the maturation of murine myeloid bone marrow-derived DC. On the one hand, IL-10 inhibits the maturation of murine myeloid DC. The addition of IL-10 to granulocyte-macrophage colony-stimulating factor (GM-CSF)-supported murine BM-derived DC cultures reduced the frequency of major histocompatibility complex (MHC) class IIbright cells. These IL-10-pretreated DC have a reduced capacity to stimulate T cells in an allogeneic mixed leucocyte reaction. On the other hand, however, and in contrast to the effects of IL-10 on human DC, we found that the addition of IL-10 from the initiation of the culture onwards induced an up-regulation of the expression of the costimulatory molecules CD40, CD80 and CD86 on murine myeloid DC, as compared to DC generated with GM-CSF only. Moreover, a subpopulation of IL-10-pretreated MHC class IIdim DC lacked the capacity to take up dextran-fluorescein isothiocyanate (FITC), a feature of DC maturation. Taken together, our data demonstrate that the generation of murine myeloid DC in the presence of IL-10 results in a population of incompletely matured MHC class IIdim CD80+ CD86+ DC. These DC lack T-cell stimulatory capacity, suggesting a role for IL-10 in conferring tolerogenic properties on murine myeloid DC.  相似文献   
3.
A study was performed during 1999-2000 on multi-transfused patients with haemophilia who are registered by the Shiraz Haemophilia Society. HBsAg, anti-HCV, and anti-HIV were checked using a second-generation enzyme-linked immunosorbent assay (ELISA). Positive tests for anti-HCV and anti-HIV were confirmed by a western blot test. Healthy blood donors were used for the control group. HBsAg, anti-HCV, and anti-HIV were positive in two (0.71%, 95% CI = 0.12-2.33), 44 (15.65%, 95% CI = 11.76-20.26), and one (0.36%, 95% CI = 0.02-1.74) of the patients, respectively. Positive sera for HBsAg, anti-HCV, and anti-HIV were found in 85 (1.07%), 47 (0.59%), and 27 (0.34%) of the control group, respectively. The rate of anti-HCV was significantly higher in the patients than in the control group (p < 0.0001). The rate of positive anti-HCV was significantly higher than that of positive HBsAg in the patients (p < 0.0001). The reverse was correct for the control group (p = 0.0008). It is concluded that HCV is the current major problem in multi-transfused haemophiliac patients and more careful pre-transfusion screening of blood for anti-HCV must be introduced in all blood banks.  相似文献   
4.
Factor XIII (FXIII) deficiency is a very rare severe autosomal bleeding disorder with a frequency of 1:2,000,000 in the general population and only a few patients have been genetically characterized so far. We report a phenotype-genotype characterization of 10 unrelated Iranian patients. Two FXIII (transglutaminase) activity assays showed no FXIII activity, except a conserved residual activity in patients receiving prophylactic substitution treatment. FXIII antigen concentrations measured by two immunoassays were comparable. Genotype characterization identified four novel mutations (2 missense and 2 small deletions) and two previously reported missense mutations in the FXIII A subunit gene (F13A). Molecular modeling was carried out to reveal the structural consequences of the missense mutations, that caused the replacement of an arginine residue involved in the formation of structurally important extensive hydrogen-bonded network. The replacements [c.320G>A (p.Arg77His) in the beta-sandwich, c.868C>T (p.Arg260Cys), c.869G>A (p.Arg260His) and c.1236G>T (p.Arg382Ser) in the core domain] resulted in the loss or impairment of such H-bonded network. Energy decomposition analysis demonstrated that this situation leads to the instability and perhaps to the incorrect folding of the A subunit, that would explain the development of severe FXIII deficiency.  相似文献   
5.
Mono-Mac-6 (MM6) human monocytes ingest IgG-opsonized particles better than other human cell lines. We compared the phagocytic signaling pathway in MM6 with human monocytes. MM6 expressed FcgammaRI at levels similar to monocytes, whereas FcRgammaII expression was approximately double. MM6 ingested IgG-opsonized erythrocytes (EIgG) in a calcium-independent manner. Incubation of MM6 with bromoenol lactone, an inhibitor of the phagocytic phospholipase (pPL), coordinately decreased phagocytosis and pPL activity. This inhibition was overcome by exogenous arachidonic acid, suggesting that phagocytosis requires pPL activation and arachidonic acid release. MM6 phagocytosis was inhibited with staurosporine and activated with diacylglycerol, supporting a role for protein kinase C (PKC) in this process. The pPL activators mastoparan and melittin restored phagocytosis to PKC-inhibited cells, suggesting that pPL lies downstream from PKC. These results suggest that the MM6 signal transduction pathway for IgG-mediated phagocytosis is similar to that of monocytes (PKC-->pPL-->arachidonic acid-->phagocytosis). The results are discussed in the context of the finding that MM6 exhibit low phagocytosis relative to monocytes and thus may represent an attractive cell line for molecular manipulation in "recovery of function" studies.  相似文献   
6.
BACKGROUND: The percentage of women requiring infrainguinal bypass graft operations continues to increase, whereas the effect of gender on postoperative outcome remains unclear. The purpose of this study was to assess the influence of gender on patient selection and outcome in patients requiring infrainguinal vein bypass grafting procedures. METHODS: This retrospective study reviewed 217 infrainguinal vein bypass grafts performed over an 8-year period. Medical records and patient interviews were used to determine study measures and outcomes. Gender and multiple covariables affecting patient survival were analyzed; postoperative complications and graft patencies were examined. Bivariate and life-table analyses were conducted, followed by multivariate analysis with the Cox proportional hazards model. RESULTS: No statistical differences existed between men and women for age, diabetes, cardiac disease, tobacco use, hypertension, stroke, renal disease, or prior contralateral bypass or major amputation. Women were more likely to be black (P =.014) and have a spliced vein graft (P =.035). No differences were noted between the 2 groups for 30-day morbidity rates-except women had more incisional complications (P =.01)-or for survival (P =.45), primary-patency (P =.57), secondary-patency (P =. 79), or limb-salvage rates (P =.40). Multivariate analysis showed that gender had no role in affecting survival rates. CONCLUSIONS: Gender does not affect graft patency, limb salvage, or survival rates. There should be no introduction of a gender bias into management of infrainguinal occlusive disease.  相似文献   
7.
8.
Detection of Epstein-Barr virus in oral squamous cell carcinoma suggests its involvement in the carcinogenesis of oral cavity. But, there are few studies on the incidence of EBV genome in squamous cell carcinomas at specific locations in the oral cavity like tongue and with different tumor progression. In this study the presence of EBV genome in tongue Squamous Cell Carcinoma (TSCC) in Iranian patients were investigated. Accordingly, a total of 94 cases with TSCC were firstly analyzed for the presence of viral genome through Nested PCR. Patients were divided into different groups based on their gender and the size, nodal involvement, grade and stage of their tumor. Results showed the presence of EBV genome in 72.3% of TSCCs with no significant difference between two genders, although slightly higher in females. Interestingly, PCR products of EBV genome showed a statistically significant higher distribution in TSCCs at IVa stage (p = 0.04), while a considerable low involvement of EBV genome was seen in T1-sized tumors. The result of this study further emphasizes the role of EBV in oral SCCs – mainly at tongue. This is the first investigation to clarify the association between EBV genome and different tumor size and stage in TSCCs; however, more studies in different regions and larger populations should be performed to be able to draw a firmed conclusion.  相似文献   
9.
Chronic rhinosinusitis is a common inflammatory condition in western countries. Nasal polyposis has different symptoms such as nasal obstruction, anterior or posterior nasal drip, reduced sense of smell, and facial pain. Medical and endoscopic treatments are the two main treatments for nasal polyposis. Our aim was to compare the efficacy of different methods on olfactory function. This is a non-randomized clinical trial study that was done on 60 patients who were divided into two groups (medical and surgical). Patients were matched based on age, history of smoking, and the severity of obstruction. The radiologist score of Lund-Mackay staging system was used to match patients in two arms of the trial based on the severity of nasal obstruction. Patients in surgery groups underwent functional endoscopic sinus surgery under general anesthesia and then received Fluticasone propionate nasal spray for 8 weeks (400 mcg bd). Patients in the medical group were only prescribed with Fluticasone propionate with the same duration and same dose as mentioned. As a result of treatment protocol, both medical and surgical group experienced improvement in olfactory function but statistical analyses revealed that surgery resulted in better resolution of symptoms. Our observation revealed that combined treatment had a better effect than medical treatment in restoring olfaction in patients with nasal polyposis.  相似文献   
10.
Despite progress made in nasal reconstruction, the restoration of a large defect, including the whole septum and mid-nasal vault structures, remains a challenge. The pericranial flap (PCF) is used widely for the reconstruction of anterior cranial fossa defects. This article presents a surgical technique for nasal lining restoration with an endoscopic PCF design. This technique was used in patients with huge intranasal tumours. Two patients with nasal eosinophilic angiocentric fibrosis were treated. The structural involvement was similar in each case. The tumour was resected completely by combined endoscopic and external methods through an open rhinoplasty approach. The resulting defect included the whole nasal septum, bilateral upper lateral cartilage, and the entire mid-nasal vault mucosal lining. Reconstruction was achieved by endoscopic PCF design for internal lining reconstruction and rib cartilage for framework repair. The first patient was followed up for 18 months and the second for 8 months. No infection occurred in the postoperative period. Framework stability and texture were good, and both nasal shapes were acceptable. In conclusion, this endoscopic PCF approach for restoring the internal nasal lining appears to be a good choice in selected cases.  相似文献   
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