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991.
Thiamine-responsive megaloblastic anaemia (TRMA) is a rare syndrome presenting with early onset non-autoimmune diabetes mellitus, megaloblastic anaemia and sensorineural deafness. We report a 16-month-old male, a youngest case of genetically confirmed TRMA syndrome in Indian phenotype, born to consanguineous parents. We found a homozygous pathogenic variant in exon 2 of the SLC19A2 gene, c.314G>A (p.Gly105Glu). The anaemia showed a good response to daily thiamine doses and was able to avoid unwanted blood transfusion. There was no benefit with regard to insulin requirement. Early detection of hearing impairment and referral to audiological treatment was possible. The report indicates that TRMA should be considered as a differential diagnosis for patients presenting with suggestive clinical symptoms which would have tremendous impact on patient management if identified early.  相似文献   
992.
993.
Transfusion related acute Lung injury (TRALI) though a serious blood transfusion reaction with a fatality rate of 5–25 % presents with acute respiratory distress with hypoxaemia and noncardiac pulmonary oedema within 6 h of transfusion. In non fatal cases, it may resolve within 72 h or earlier. Although reported with an incidence of 1:5000, its true occurrence is rather unknown. Pathogenesis is believed to be related to sequestration and adhesion of neutrophils to the pulmonary capillary endothelium and its activation leading to its destruction and leaks. The patient’s underlying condition, anti-neutrophil antibody in the transfused donor plasma and certain lipids that accumulate in routinely stores blood and components are important in its aetiopathogenesis. Patient’s predisposing conditions include haematological malignancy, major surgery (especially cardiac), trauma and infections. The more commonly incriminated products include fresh frozen plasma (FFP), platelets (whole blood derived and apheresis), whole blood and Packed RBC. Occasional cases involving cryoprecipitate and Intravenous immunoglobulin (IVig) have also been reported. We present a 15 year single institution experience of TRALI, during which we observed 9 cases among 170,871 transfusions, giving an incidence of 1:19,000. We did not encounter cases of haematological malignancy or cardiac surgery in our TRALI patients. Among the blood products, that could be related to TRALI in our patients included solitary cases receiving cryoprecipitate, IVIg, and recombinant Factor VII apart from platelets and FFP. All patients were treated with oxygen support. Six patients required mechanical ventilation. Off label hydrocortisone was given to all patients. There were no cases of fatality among our patients.  相似文献   
994.
Hemophagocytosis shows engulfment of hematopoietic cells by histiocytes and is a property generally associated with cells of the histiocytic lineage. It can be familial or is seen in a wide spectrum of acquired disorders. Hemophagocytosis by leukemic blasts is an uncommon phenomenon and has been reported mainly in acute myeloid leukemia. Its association with acute lymphoblastic leukemia is rare. We present a case of hemophagocytosis by blasts in the bone marrow in a 11 year old boy with T cell-acute lymphoblastic leukemia.  相似文献   
995.
Angiogenesis, or new blood vessel formation, is an important process in the pathogenesis of several diseases and thus has been targeted for the prevention and treatment for many disorders. However, the anti-angiogenic agents that are currently in use are mainly synthetic compounds and humanized monoclonal antibodies, which are either expensive or toxic, thereby limiting their use in many patients. Therefore, it is necessary to identify less toxic, inexpensive, novel and effective anti-angiogenic molecules. Several studies have indicated that natural plant products can meet these criteria. In this review, we discuss the anti-angiogenic properties of natural compounds isolated from plants and the molecular mechanisms by which these molecules act. Finally, we summarize the advantages of using plant products as anti-angiogenic agents. Compared with currently available anti-angiogenic drugs, plant products may not only have similar therapeutic potential but are also inexpensive, less toxic, and easy to administer. However, novel and effective strategies are necessary to improve their bioavailability for clinical use.  相似文献   
996.
Aberrant activation of the hypoxia inducible factor (HIF) pathway causing overexpression of angiogenic genes, like vascular endothelial growth factor (VEGF), is one of the underlying causes of ocular neovascularization (NV) and metastatic cancer. Consistently, along with surgical interventions, a number of anti-VEGF agents have been approved by FDA for the treatment of ocular neovascular diseases. These anti-VEGF agents, like ranibizumab/lucentis, have revolutionized the treatment in the past decade. However, substantial vision improvement is observed only in a subset of age-related macular degeneration patients receiving ranibizumab. Further, all current therapies are associated with limitations and side effects. For example, surgeries cause tissue destruction and inflammation while anti-VEGF therapies are expensive, require repeated administration, and offer temporary relief from vascular leakage. These factors impose significant cost and treatment burdens to both the patient and society. With an aging population in most western countries with a continually increasing number of patients on lifelong treatment for these retinal diseases, the focus of ocular drug development for neovascular diseases will be to improve efficacy while reducing treatment costs. Blocking the HIF pathway, a major regulator of ocular NV and cancer, offers an appealing therapeutic strategy. Therefore, this review summarizes HIF inhibitors that have been recently evaluated for the treatment of different cancers and ischemic retinopathies.  相似文献   
997.
Type 2 diabetes (T2DM) is a common, complex disease that poses a substantial burden on individual and population health, but we have relatively limited understanding of its underlying pathophysiology. Observational studies have highlighted large numbers of risk factors for T2DM, some of which are modifiable through behavioural or pharmacological intervention. Determining which of these risk factors plays a causal role in the development of T2DM has been a challenge, but Mendelian randomisation (MR) studies are harnessing genetic data in population studies to offer new insights. Using evolving analytical methods, MR studies continue to address questions of causality related to T2DM, including exploring the roles of adiposity, blood lipids and inflammation. The causal roles of a number of important modifiable risk factors have been confirmed by MR studies, while the relevance of others has been called into question. As more MR studies are conducted, methods are developed and refined in order to make the most efficient and reliable use of available genetic and phenotypic data. In this review, the design and findings of some important MR studies related to T2DM are explored and their relevance for translation to clinical practice considered.  相似文献   
998.
In both epidemiologic and genetic studies, increased levels of Lp(a) have been associated with increased risk for cardiovascular diseases as well as aortic stenosis. However, until recently, it has been difficult to lower levels of Lp(a). Diet and lifestyle have little effect on plasma levels of Lp(a) which are mainly genetically determined. Emerging therapeutic agents which have recently become available, or which are undergoing clinical trials, can significantly lower Lp(a) levels. Studies with these agents will hopefully be able to provide more direct information whether reductions in Lp(a) will reduce CVD events independently of reduction in LDL-cholesterol levels.  相似文献   
999.
CRUSADE (Can Rapid risk stratification of Unstable angina patients Suppress Adverse outcomes with Early implementation of the ACC/AHA guidelines) risk score can independently predict major bleeding events in patients with non-ST elevation myocardial infarction whereas the discriminative capacity is moderate. Whether adding platelet reactivity on top of CRUSADE score improves the prognostic performance for bleeding remains unclear. 512 patients with acute coronary syndrome (ACS) underwent successful percutaneous coronary intervention were enrolled and 1-year data were available. CRUSADE risk score was calculated at hospital admission and P2Y12 reaction unit (PRU) value was measured by VerifyNow P2Y12 assay. Thirty-five (6.8 %) patients experienced major bleeding events within 1-year follow-up. Patients who developed bleeding complications had higher CRUSADE score (37.5 ± 9.4 vs. 29.0 ± 10.2, p < 0.001) and lower PRU value (149.7 ± 57.1 vs. 196.4 ± 51.4, p < 0.001) than those did not. Both CRUSADE score and platelet reactivity were independently associated with bleeding. Kaplan–Meier analysis showed that patients with high CRUSADE score plus low platelet reactivity had significantly elevated risk for bleeding (HR 7.905, 95 % CI 2.623–23.822, p < 0.001). Compared to CRUSADE score alone, adding platelet reactivity on top of CRUSADE score offered a discriminative increment which was demonstrated by c-statistic (0.827 vs. 0.732, p = 0.011), as well as net reclassification improvement (NRI = 0.258, p < 0.001) and integrated discrimination improvement (IDI = 0.022, p = 0.002). After successful coronary stent implantation in patients with ACS, combining CRUSADE score with platelet reactivity yielded more accurate predictive value for 1-year bleeding risk.  相似文献   
1000.
Immature platelets—also termed reticulated platelets (RP)—are platelets newly released into the circulation, and have been associated with a variety of pathological thrombotic events. They can be assessed by flow cytometry after staining with thiazole orange (TO) or by using a module added to a fully automated analyzer that is currently in wide clinical use and expressed as a fraction of the total platelet count (IPF). We sought to assess the correlation and agreement between these two methods. IPF was measured using Sysmex XE 2100—and at the same time point- we used TO staining and flow cytometry to measure RP levels. Two different gates were used for the flow cytometry method, 1 and 0.5 %. Measurements from the automated analyzer were then compared separately to measurements performed using each gate. Agreement between methods was assessed using Bland–Altman method. Pearson’s correlation coefficient was also calculated. 129 subjects were enrolled and stratified into 5 groups: (1) Healthy subjects, (2) End stage renal disease, (3) Chronic stable coronary artery disease, (4) Post Coronary artery bypass surgery, (5) Peripheral thrombocytopenia. Median IPF levels were increased for patients in groups 2, 3, 4 and 5 (4.0, 4.7, 4.3, and 8.3 % respectively) compared to healthy subjects (2.5 %) p = 0.0001. Although the observed correlation between the two methods tended to be good in patients with high IPF values (i.e., group 5), the overall observed correlation was poor (Pearson’s correlation coefficient r = 0.27). Furthermore, there was poor agreement between the two methods in all groups. Despite the good correlation that was observed between the two methods at higher IPF values, the lack of agreement was significant.  相似文献   
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