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21.
The increasing availability of biosimilar medicines in Middle Eastern regions may provide an opportunity to increase the number of rheumatology patients who have access to traditionally more expensive biologic medicines. However, as well as a lack of real-world data on the use of biosimilar medicines in practice, the availability of intended copies in the region may undermine physician confidence in prescribing legitimate biosimilar medicines. There is a need for regional recommendations for healthcare professionals to ensure that biosimilar drugs can be used safely. Therefore, a literature search was performed with the aim of providing important recommendations for the regulation and use of biosimilar medicines in the Middle East from key opinion leaders in rheumatology from the region. These recommendations focus on improving the availability of relevant real-world data, ensuring that physicians are aware of the difference between intended copies and true biosimilars and ensuring that physicians are responsible for making any prescribing and switching decisions.  相似文献   
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23.
Chronic lymphocytic leukemia (CLL) remains an incurable malignancy, urging for the identifcation of new molecular targets for therapeutic intervention. CLL cells rely on overexpression and hyperactivation of the ubiquitous serine/threonine protein kinase CK2 for their viability in vitro. CIGB-300 is a cell-permeable selective CK2 inhibitor peptide undergoing clinical trials for several cancers. Here, we show that CIGB-300 promotes activation of the tumor suppressor PTEN and abrogates PI3K-mediated downstream signaling in CLL cells. In accordance, CIGB-300 decreases the viability and proliferation of CLL cell lines, promotes apoptosis of primary leukemia cells and displays antitumor efcacy in a xenograft mouse model of human CLL. Our studies provide pre-clinical support for the testing and possible inclusion of CK2 inhibitors in the clinical arsenal against CLL.  相似文献   
24.
Hemophagocytic lymphohistiocytosis (HLH) embraces the frequently indistinguishable conditions of familial hemophagocytic lymphohistiocytosis (FHL) and virus-associated hemophagocytic syndrome (VAHS). Without therapy FHL is invariably fatal, but successful therapy, including chemotherapy and immunotherapy followed by bone marrow transplantation (BMT), has been presented. To clarify the outcome of HLH in a developing country, with regard to clinical, laboratory, and genetic features, a nationwide study on all patients diagnosed with HLH in Oman during the 5-year period 1997-2001 was performed. In 5 patients and their families, mutational analysis was made. Thirteen patients with HLH were identified, 5 of whom had clinical manifestations of central nervous system involvement at presentation. In none of the patients could an infectious cause be identified. Ten children were referred late in the disease course, and the concern about starting chemotherapy before exclusion of an acute viral infection resulted in delayed treatment in some patients. Two children were started early on the HLH-94-therapy followed by successful BMT in one child. In the successfully transplanted child, the response to intrathecal hydrocortisone appeared to be better than standard therapy with intrathecal methotrexate. Finally, a novel missense mutation in the perforin gene was identified in 2 patients and their family members, causing a transition of proline to threonine at codon 89. Early diagnosis and treatment is important to improve outcome. Intrathecal corticosteroids may be considered, in addition to intrathecal methotrexate, in certain patients. Since the novel perforin mutation has been reported in only 2 patients from Oman, and since similar polymorphism in the sequencing data of the members of their families has been identified, a founder effect is possible in this population.  相似文献   
25.
Chronic mesenteric ischemia classically presents as “intestinal angina” with generalized postprandial abdominal pain lasting up to 3 hours. Over time, these episodes can become much more intense and ultimately lead to sitophobia with significant weight loss. Symptoms are not specific and often mistakenly attributed to other gastrointestinal etiologies such as peptic ulcer disease. Gastric ulcerations as a direct result of mesenteric ischemia have been reported but are relatively rare because of the rich collateral blood supply to the stomach. Therefore, a diagnosis of ischemic gastropathy is seldom entertained in patients presenting with abdominal pain and gastriculcers.  相似文献   
26.

Background

Diabetic foot ulceration (DFU) is a serious diabetic complication that can progress to amputation and since SIRT1 regulates glucose metabolism, inflammation, and oxidative stress which are the major contributors in diabetic complications, So we aimed to discuss its role as an epigenetic biomarker in DFU and highlight its link to oxidative stress and inflammatory cytokines.

Method

60 DM patients were enrolled in the study, 30 without DFU and 30 with DFU in addition to 15 healthy subjects (control group). SIRT1 mRNA relative gene expression was assessed. Catalase activity, advanced glycation end products (AGEs), tumor necrosis factor alpha (TNFα), interleukin 6 (IL-6) and High mobility group box1 (HMGB1) levels were measured. DNA fragmentation was also performed.

Result

SIRT1 expression and catalase activity were significantly decreased in diabetic patients compared to control group with the lowest levels in DFU patients, TNFα, IL-6, HMGB 1 and AGEs levels were significantly higher in the diabetic patients compared to control group with the highest levels in DFU patients. DNA fragmentation was more profound in DFU patients.

Conclusion

The study revealed that SIRT1 mRNA expression can be considered as a novel biomarker in DFU being a major player involved in its pathogenesis.  相似文献   
27.
Some limited models have been suggested to determine the conductivity of polymer carbon nanotube (CNT) nanocomposites (PCNTs). However, earlier models (e.g., the Kovacs model) cannot properly consider the roles of the interphase regions or tunneling properties on the percolation threshold and subsequent conductivity of PCNTs. In this paper, the Kovacs model is further developed by assuming that the CNT, interphase, and tunneling regions are separate phases. Also, some simple equations are provided to calculate the percolation threshold as well as the volume fractions and resistances of the CNT, interphase, and tunneling regions in conductive networks. The experimental conductivity results for several samples are compared with the predictions of the developed model. In addition, the calculations of the developed model at different parameter levels are explained and justified. The conductivity calculations show good agreement with the experimental data. Moreover, the developed model reasonably explains the roles of the different parameters on the conductivity. For example, long, thin, and straight CNTs efficiently improve the conductivity because they form large networks in the nanocomposites. Additionally, a thick interphase enlarges the conductive networks, resulting in a desirable conductivity. The conductivity of PCNTs only depends on the tunneling resistance; this is the case because the poor resistance/significant conductivity of the CNT and interphase regions do not influence the conductivity. The developed equations can replace conventional approaches for predicting the conductivity of nanocomposites.

Some limited models have been suggested to determine the conductivity of polymer carbon nanotube (CNT) nanocomposites (PCNTs).  相似文献   
28.
Clinical Rheumatology - The prevalence of sarcopenia with osteoporosis results in a higher risk of falling and fractures. It was noted that patients who had completed their planned 5-year denosumab...  相似文献   
29.
The coronavirus disease 2019 (COVID-19) pandemic is a threat worldwide for individuals of all ages, including children. Gastrointestinal manifestations could be the initial presenting manifestation in many patients, especially in children. These symptoms are more common in patients with severe disease than in patients with non-severe disease. Approximately 48.1% of patients had a stool sample that was positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viral RNA. Children typically form 1%-8% of all laboratory-confirmed cases of SARS-CoV-2. Gastrointestinal manifestations of COVID-19 in children are not rare, with a prevalence between 0 and 88%, and a wide variety of presentations, including diarrhoea, vomiting, and abdominal pain, can develop before, with or after the development of respiratory symptoms. Atypical manifestations such as appendicitis or liver injury could also appear, especially in the presence of multisystem inflammatory disease. In this review, we discussed the epidemiology of COVID-19 gastrointestinal diseases in children as well as their implications on the diagnosis, misdiagnosis, prognosis, and faecal-oral transmission route of COVID-19 and the impact of gastrointestinal diseases on the gut microbiome, child nutrition, and disease management.  相似文献   
30.
OBJECTIVEEmerging data from animal and human pilot studies suggest potential benefits of glucagon-like peptide 1 receptor agonists (GLP-1RA) on lung function. We aimed to assess the association of GLP-1RA and chronic lower respiratory disease (CLRD) exacerbation in a population with comorbid type 2 diabetes (T2D) and CLRD.RESEARCH DESIGN AND METHODSA new-user active-comparator analysis was conducted with use of a national claims database of beneficiaries with employer-sponsored health insurance spanning 2005–2017. We included adults with T2D and CLRD who initiated GLP-1RA or dipeptidyl peptidase 4 inhibitors (DPP-4I) as an add-on therapy to their antidiabetes regimen. The primary outcome was time to first hospital admission for CLRD. The secondary outcome was a count of any CLRD exacerbation associated with an inpatient or outpatient visit. We estimated incidence rates using inverse probability of treatment weighting for each study group and compared via risk ratios.RESULTSThe study sample consisted of 4,150 GLP-1RA and 12,540 DPP-4I new users with comorbid T2D and CLRD. The adjusted incidence rate of first CLRD admission during follow-up was 10.7 and 20.3 per 1,000 person-years for GLP-1RA and DPP-4I users, respectively, resulting in an adjusted hazard ratio of 0.52 (95% CI 0.32–0.85). For the secondary outcome, the adjusted incidence rate ratio was 0.70 (95% CI 0.57–0.87).CONCLUSIONSGLP-1RA users had fewer CLRD exacerbations in comparison with DPP-4I users. Considering both plausible mechanistic pathways and this real-world evidence, potential beneficial effects of GLP-1RA may be considered in selection of an antidiabetes treatment regimen. Randomized clinical trials are warranted to confirm our findings.  相似文献   
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