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BackgroundIron deficiency anemia (IDA) is the highest nutritional deficiency worldwide. It is a multifactorial disease, with a higher morbidity rate. TMPRSS6 polymorphisms importantly rs855791 is found to play an essential role in iron homeostasis in the human body. The rs855791 (T > C) polymorphism is highly associated with iron levels, and multiple blood parameters, leading to IDA. The role of TMPRSS6 rs855791 polymorphism and the significance of complete blood count (CBC) parameters in the pathogenesis of IDA is not yet studied in the Pakistani population.MethodsWe enrolled 113 cases and 136 controls to conduct a case control study. Complete blood count (CBC) and iron parameters were analyzed for association studies. PCR-RFLP based genotyping was performed.ResultsThe TMPRSS6 rs855791 (T > C) polymorphism is significantly associated with IDA pathogenesis as observed in the codominant model and recessive models (P < 0.05, OR: 1.5 and 95% CI: 0.9, 2.6, P < 0.05, OR: 0.5 and 95% CI: 0.2, 0.9 respectively). Elderly women among cases (30–49 years) were found to be more susceptible to IDA (P < 0.05, AOR: 2.1 and 95% CI: 1.0, 4.2). The most significant parameters associated with IDA were red blood cell count (RBC) and hematocrit (Hct%) (P < 0.05, AOR: 16.5, 95% CI: 7.6, 35.9 and P < 0.05, AOR: 10.1, 95% CI: 2.5, 41.6, respectively).ConclusionTMPRSS6 polymorphism at rs855791 (T > C) is significantly associated with IDA susceptibility in reproductive age women in Pakistan. Age, RBC count and Hct% are found to play an important role in IDA pathogenesis in our study population.  相似文献   
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Vimentin-typing was carried out on various normal and neoplastic tissues using four anti-vimentin antibodies in order to evaluate the effect of different fixation treatments on tissue reactivity in comparison to the results obtained on frozen sections. All antisera were reactive on frozen material; on paraffin embedded material staining of tissues depended on the type of fixation method applied (formalin, methacarn or absolute alcohol) and each antibody behaved differently in relation to the fixative used. Only mesenchymal normal structures were revealed on frozen material whilst on paraffin embedded material three of the four antibodies reacted also with non-mesenchymal normal structures (epithelia, central and peripheral nervous system cells). All four antibodies decorated, regardless of treatment, neoplastic cells of mesenchymal and non-mesenchymal derivation, but not germ cells or germ cell tumors. The reactivity of vimentin to its specific antibodies depends on the fixative used: therefore, in routine pathology more than one antiserum should be available for testing. Furthermore, given the variety of non-mesenchymal structures stained by the anti-vimentin antibodies, the differential diagnosis of undifferentiated tumors must not be based on vimentin positivity alone. The expression of vimentin by non-mesenchymal neoplastic cells seems to parallel that of normal tissues during embryogenesis; therefore, this intermediate filament appears to be not only a marker of mesenchymal cells but also of many immature elements.  相似文献   
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Abstract

Forming coordination complexes with nucleoside analogues may be helpful in studying anti-tumour activity of them. Therefore, to improve the clinical efficacy of nucleoside analogue and design new ones, a new fluorescent platinum (Pt) complex with anti-human immunodeficiency virus drug didanosine (ddI); K[PtCl(OCH3)2(ddI)]; was synthesized and characterized. The ultraviolet–visible (UV-vis) spectroscopy, infrared, thermogravimetric analysis, mass assignments and elemental analysis confirmed the preparation of the complex. The molecular ion peaks seen at the positive mass spectrum of Pt complex confirm coordination of the drug to metal centre. The interaction of this complex with calf thymus DNA (ct-DNA) was studied using several spectroscopic techniques such as UV absorption, fluorescence spectroscopy and dynamic viscosity measurements. Hyperchromism of the band in the UV-vis spectra and the intrinsic binding constant (0.56?±?0.25) × 104 M?1, decreasing in Hoechst-DNA fluorescence by adding Pt complex concentration and also relatively small changes in DNA viscosity indicated that this complex could interact as a groove-binder. According to the UV spectra and the fluorescence quenching of the complex in our case seems to be primarily caused by complex formation between the Pt complex and DNA. The thermodynamic parameters showed that hydrogen bond and van der Waals interactions play main roles in the binding of Pt complex to ct-DNA. The free energy values are negative, showing the spontaneity of the Pt complex–DNA binding. The docking simulation was performed and the results confirm a preference of groove site of synthesized complex on DNA helix. The knowledge gained from this study will be helpful to further understand the DNA binding mechanism and can also provide much fruitful information for designing a new type of anti-cancer drugs.

Communicated by Ramaswamy H. Sarma  相似文献   
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BackgroundSodium-glucose cotransporter-2 (SGLT2) inhibitors (SGLT2i) showed benefits in type 1 diabetes mellitus (T1DM), but the risk of diabetic ketoacidosis (DKA) limits their use. Ability to predict DKA risk and therapeutic responses would enable appropriate patient selection for SGLT2i. We conducted a meta-analysis and meta-regression of randomized controlled trials (RCTs) evaluating SGLT2i in T1DM to assess moderators of the relative risk (RR) of DKA, of glycemic (HbA1c, fasting plasma glucose, continuous glucose monitoring parameters, insulin dose, and insulin sensitivity indices) and non-glycemic (body mass index (BMI), systolic BP, renal function, albuminuria, and diabetic eye disorders) efficacy, and of other safety outcomes (including hypoglycemia, infections, major adverse cardiovascular events, and death).Methods and findingsWe searched MEDLINE, Cochrane Library, EMBASE, ClinicalTrials.gov, Cochrane CENTRAL Register of Controlled Trials, and other electronic sources through August 30, 2020, for RCTs comparing SGLT2i with active comparators or placebo in adult patients with T1DM. Reviewers extracted data for relevant outcomes, performed random effects meta-analyses, subgroup analyses, and multivariable meta-regression. The strength of evidence was summarized with the GRADE approach. Among 9,914 records identified, 18 placebo-controlled RCTs (7,396 participants, 50% males, mean age 42 y (range 23 to 55 y), 5 different SGLT2i evaluated), were included. Main outcome measures were effect sizes and moderators of glycemic and non-glycemic efficacy and of safety outcomes. In a multivariable meta-regression model, baseline BMI (β = 0.439 [95% CI: 0.211, 0.666], p < 0.001) and estimated glucose disposal rate (eGDR) (β = −0.766 [−1.276, −0.256], p = 0.001) were associated with the RR of DKA (RR: 2.81; 95% CI:1.97, 4.01; p < 0.001, R2 = 61%). A model including also treatment-related parameters (insulin dose change-to-baseline insulin sensitivity ratio and volume depletion) explained 86% of variance across studies in the risk of DKA (R2 = 86%). The association of DKA with a BMI >27 kg/m2 and with an eGDR <8.3 mg/kg/min was confirmed also in subgroup analyses. Among efficacy outcomes, the novel findings were a reduction in albuminuria (WMD: −9.91, 95% CI: −16.26, −3.55 mg/g, p = 0.002), and in RR of diabetic eye disorders (RR: 0.27[0.11, 0.67], p = 0.005) associated with SGLT2i. A SGLT2i dose-response gradient was consistently observed for main efficacy outcomes, but not for adverse events (AEs). Overall, predictors of DKA and of other AEs differed substantially from those of glycemic and non-glycemic efficacy. A limitation of our analysis was the relatively short (≤52 weeks) duration of included RCTs. The potential relevance for clinical practice needs also to be confirmed by real-world prospective studies.ConclusionsIn T1DM, the risk of DKA and main therapeutic responses to SGLT2i are modified by baseline BMI and insulin resistance, by total insulin dose reduction-to-baseline insulin sensitivity ratio, and by volume depletion, which may enable the targeted use of these drugs in patients with the greatest benefit and the lowest risk of DKA.

Giovanni Musso and colleagues conduct a meta-analysis to identify risk factors of diabetic ketoacidosis in patients with Type 1 diabetes taking SGLT2 inhibitors.  相似文献   
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