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961.
《Endocrine practice》2021,27(2):110-117
ObjectiveType 1 diabetes (T1D) is frequently associated with other autoimmune diseases (AIDs). Although most of T1D patients are sporadic cases (S-T1D), 10% to 15% have a familial form (F-T1D) involving 2 or more first-degree relatives. This study evaluated the effect of T1D family aggregation and age onset on AIDs occurrence.MethodsIn this observational, cross-sectional, case-control, single center study, we enrolled 115 F-T1D and 115 S-T1D patients matched for gender, age, T1D age onset, and duration. With respect to T1D age onset (before or after 18 years), both groups were further subdivided into young- or adult-onset F-T1D and young- or adult-onset S-T1D. The presence of organ-specific antibodies and/or overt AIDs was evaluated.ResultsThe F-T1D group had a higher percentage of AIDs (29.8% vs 18.4%, P = .04) and a significant earlier onset of AIDs at Cox regression analysis (P = .04) than the S-T1D group. Based on multivariate analysis, the adult-onset F-T1D subgroup had the highest prevalence of both additional organ-specific antibodies (60.5%) and overt AIDs (34.9%), whereas the adult S-T1D subgroup was the least frequently involved (29.1% and 12.7%, respectively). In F-T1D patients, offsprings develop T1D and AIDs earlier than their parents do.ConclusionsIn T1D patients, familial aggregation and adult-onset of T1D increase the risk for coexistent AIDs. These clinical predictors could guide clinicians to address T1D patients for the screening of T1D-related AIDs.  相似文献   
962.
ObjectiveThe prevalence of chronic kidney disease (CKD) in the United States is 13% of the general population. Among those with CKD, diabetic nephropathy is the leading cause of end-stage renal disease. This is a retrospective study examining the effect of long-term use of dipeptidyl peptidase-4 (DPP-4) inhibitors on all-cause mortality and progression of renal disease in the veteran population.MethodsData was extracted using the Veterans Administration Informatics and Computing Infrastructure. A large cohort of veterans diagnosed with type 2 diabetes mellitus were used to identify patients on DPP-4 inhibitors and without DPP-4 inhibitors. Groups were compared to determine the effect of DPP-4 inhibitors on the progression of CKD and all-cause mortality. Data were analyzed using SAS.ResultsSubjects in the treatment group (n = 40 558) had baseline variables (age, body mass index, race) similar to the control group (n = 40 558). Diabetes control improved in the treatment group (HgbA1c, 8.3% [67 mmol/mol] to 7.8% [62 mmol/mol]; P < .001) but not in the control group (HgbA1c, 7.4% [57 mmol/mol] to 7.3% [56 mmol/mol]). New diagnoses of heart failure and coronary artery bypass grafts were clinically significant (odds ratios = 0.66 and 0.52). No change in progression of CKD was seen in either group. All-cause mortality was reduced by 59%.ConclusionWe conclude that DPP-4 inhibitors are associated with a significant reduction in all-cause mortality independent of glucose control, albeit with no clear cause, including obtainable cardiovascular outcomes. Our data is consistent with prior trials in that DPP-4 inhibitors did not show a significant change in serum creatinine or microalbuminuria.  相似文献   
963.
ObjectiveInfection with SARS-CoV-2 induces a proinflammatory state that causes hyperglycemia and may precipitate diabetic ketoacidosis (DKA) in patients with known or new-onset diabetes. We examined the trends in new-onset diabetes and DKA prior to and following the onset of the COVID-19 pandemic.MethodsThis single-center retrospective observational study included pediatric patients (aged 0 to <18 years) hospitalized with new-onset type 1 diabetes or type 2 diabetes (T2D) before (March 1, 2018, to February 29, 2020) and after (March 1, 2020 to December 31, 2020) the pandemic onset. Demographic, anthropometrics, laboratory and clinical data, and outcomes were obtained.ResultsAmong 615 children admitted with new-onset diabetes during the entire study period, 401 were admitted before the pandemic onset, and 214 were admitted after the pandemic onset. Children admitted with new-onset diabetes in the postpandemic period were significantly more likely to present with DKA (odds ratio, 1.76; 95% confidence interval, 1.24-2.52) than in the prepandemic phase. Children with DKA after the pandemic onset had higher lengths of hospitalization and were significantly more likely to experience severe DKA (odds ratio, 2.17; 95% confidence interval, 1.34-3.52). A higher proportion of children with DKA admitted to the pediatric intensive care unit required oxygen support after the pandemic onset than before the pandemic onset (8.85% vs 1.92%). Most cases of T2D with DKA occurred following the onset of the pandemic (62.5%).ConclusionA significant increase in T2D cases occurred following the onset of the COVID-19 pandemic with a greater risk of DKA and severe ketoacidosis. Racial disparity was evident with a higher proportion of Black and American Indian children presenting with ketoacidosis following the pandemic onset.  相似文献   
964.
ObjectiveData for the association between diabetes and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) susceptibility are conflicting. We aimed to evaluate this association using an analytical cross-sectional study design.MethodsStudy participants were recruited from endocrine clinics of our hospital and belonged to 3 groups: group 1 (type 1 diabetes mellitus [T1DM]), group 2 (type 2 diabetes mellitus [T2DM]), and group 3 (controls). All participants submitted blood samples for SARS-CoV-2 S1/S2 immunoglobulin G antibody test (LIAISON; DiaSorin) and were interviewed for a history of documented infection.ResultsWe evaluated a total of 643 participants (T1DM, 149; T2DM, 160; control, 334; mean age, 37.9 ± 11.5 years). A total of 324 (50.4%) participants were seropositive for SARS-CoV-2. The seropositivity rate was significantly higher in the T1DM (55.7% vs 44.9%, P = .028) and T2DM (56.9% vs 44.9%, P = .013) groups than in the control group. The antibody levels in seropositive participants with T1DM and T2DM were not significantly different from those in seropositive controls. On multivariable analysis, low education status (odds ratio [OR], 1.41 [95% CI, 1.03-1.94]; P = .035), diabetes (OR, 1.68 [95% CI, 1.20-2.34]; P = .002), and overweight/obesity (OR, 1.52 [95% CI, 1.10-2.10]; P = .012) showed a significant association with SARS-CoV-2 seropositivity. The association between diabetes and SARS-CoV-2 seropositivity was found to further increase in participants with coexisting overweight/obesity (adjusted OR, 2.63 [95% CI, 1.54-4.47]; P < .001).ConclusionSARS-CoV-2 seropositivity, assessed before the onset of the national vaccination program, was significantly higher in participants with T1DM and T2DM than in controls. The antibody response did not differ between seropositive participants with and without diabetes. These findings point toward an increased SARS-CoV-2 susceptibility for patients with diabetes, in general, without any differential effect of the diabetes type.  相似文献   
965.
ObjectiveTo determine the prevalence of obesity and assess the cardiometabolic risk profile and treatments associated with obesity management in the type 1 diabetes mellitus adult population.MethodsWe reviewed the records of all patients with type 1 diabetes mellitus seen in our institution’s outpatient endocrinology clinic between 2015 and 2018. We stratified the patients into 4 weight categories on the basis of body mass index (BMI) (normal, overweight, obesity class I, and combined obesity class II and III) and evaluated their associated clinical characteristics and relevant medications.ResultsOf 451 patients, 64% had a BMI of >25 kg/m2, and 25% had a BMI of ≥30 kg/m2. Over 40% of patients with a BMI of >30 kg/m2 had a history of cardiovascular disease. The off-label use of the glucagon-like peptide 1 receptor agonist was 12% and the sodium glucose cotransporter 2 inhibitor use was 5% in those with obesity. Only 2 patients were prescribed phentermine and 3 had undergone bariatric surgery. Hemoglobin A1C and low-density lipoprotein did not significantly differ between the normal weight and obesity groups. The obesity groups had significantly higher levels of median triglycerides and lower high-density lipoprotein than the normal weight group.ConclusionObesity was prevalent in a population of patients with type 1 diabetes mellitus seen in a specialty clinic. Those with obesity had a higher prevalence of cardiovascular disease than their normal weight counterparts. The use of weight loss medications was scarce. Studies exploring the safety and efficacy of obesity-targeted therapy in the type 1 diabetes mellitus population are needed.  相似文献   
966.
Blood coagulation mechanisms forming a blood clot and preventing hemorrhage have been extensively studied in the last decades. Knowing the mechanisms behind becomes very important particularly in the case of blood vessel diseases. Real‐time and accurate diagnostics accompanied by the therapy are particularly needed, for example, in diseases related to retinal vasculature. In our study, we employ for the first time fluorescence hyperspectral imaging (fHSI) combined with the spectral analysis algorithm concept to assess physical as well as functional information of blood coagulation in real‐time. By laser‐induced local disruption of retinal vessels to mimic blood leaking and subsequent coagulation and a proper fitting algorithm, we were able to reveal and quantify the extent of local blood coagulation through direct identification of the change of oxyhemoglobin concentration within few minutes. We confirmed and illuminated the spatio‐temporal evolution of the essential role of erythrocytes in the coagulation cascade as the suppliers of oxygenated hemoglobin. By additional optical tweezers force manipulation, we showed immediate aggregation of erythrocytes at the coagulation site. The presented fluorescence‐based imaging concept could become a valuable tool in various blood coagulation diagnostics as well as theranostic systems if coupled with the laser therapy.  相似文献   
967.
Objective: To assess the independent effect of prepregnancy BMI on the risk of postpartum anemia. Research Methods and Procedures: Pregnant women from North Carolina who enrolled in the Iron Supplementation Study at their first prenatal visit at <20 weeks gestation and who delivered a live infant were followed to the postpartum visit (n = 439). BMI had a curvilinear relation in the logit of postpartum anemia; therefore, a restricted quadratic spline with three knots at the inflection points was used to specify BMI. Multiple log binomial regression was used to quantify the relation between prepregnancy BMI and postpartum anemia after adjusting for maternal ethnicity/race, education, smoking, initial hemoglobin concentration, and prenatal iron supplementation. Results: Prevalence of postpartum anemia was 19.1%. After adjusting for confounders, we found that risk of postpartum anemia was similar for women with BMI values from 17 to 24 compared with women with a BMI of 20. Adjusted relative risk increased as BMI increased from 24 to 38. Women with a BMI of 28 had ~1.8 times the postpartum anemia risk of a woman with a BMI of 20 (95% confidence interval 1.3, 2.5), and obese women with a BMI of 36 had ~2.8 times the risk (95% confidence interval 1.7, 4.7). Discussion: These data suggest that high prepregnancy BMI substantially increases the risk of postpartum anemia. Postpartum anemia screening and iron supplementation of overweight and obese women may be warranted.  相似文献   
968.
The atomic and electronic structures of heme complexes with His, Gly, and Cys residues (Heme–His, Heme–Gly, and Heme–Cys) in the fifth coordination position of the Fe atom and with oxygen and nitrogen oxide molecules in the sixth Fe position were studied by the semiempirical quantum-chemical method PM3. A comparative analysis of internuclear distances showed that the strength of chemical bonding between the ligand molecules (oxygen and nitrogen oxide) is greater for Heme–Cys than for Heme–His and Heme–Gly complexes. Consequently, the strengthening of the chemical bond of the oxygen (or nitrogen oxide) molecule with Heme–Cys substantially weakens the chemical bond in the ligand molecule. The Mulliken population analysis showed that the electronic density of ligand (oxygen or nitrogen oxide) p-orbitals is transferred to the d-orbitals of the Fe atom, whose charge, calculated according to the Mulliken analysis, formally becomes negative. In the Heme–His complex with oxygen, this charge is substantially greater than in the complex with NO, and the oxygen molecule becomes polarized. No oxygen polarization is observed in the Heme–Cys complex, and the electron density (judging from the change in the Fe charge) is transferred to the coordinated sulfur atom. This is also characteristic of Heme–Cys complexes with nitrogen oxide. An analysis of charges on the atoms indicates that the character of chemical bonding of the oxygen molecule in Heme–Cys and Heme–Gly complexes is similar and basically differs from that in the case of the Heme–His complex.  相似文献   
969.
H Z Lu  B L Currie  M E Johnson 《FEBS letters》1984,173(1):259-263
We have synthesized a spin-label analog of phenylalanine as a competitive inhibitor probe of the sickle hemoglobin aggregation process. Sickle hemoglobin gelation measurements indicate that the spin-label phenylalanine analog is a potent inhibitor of deoxy sickle hemoglobin aggregation. We have also used spin label EPR and high-resolution proton NMR to study the interaction of the phenylalanine analog with hemoglobin, and find that the kinetic off-rate is comparable to, or slower than the hemoglobin rotational rate (i.e., greater than or equal to 10(8) s-1), and that at least one, and perhaps two significant localized interaction region(s) exist within a few angstroms of the beta chain N- and C-termini. Correlation with other known structural information suggests that the observed interaction sites may be relevant to the mechanism for inhibition of sickle hemoglobin aggregation.  相似文献   
970.
Primary sequences for the remaining two members (GMH2, GMH3) of the group of three major monomeric hemoglobins from the marine annelid Glycera dibranchiata have been obtained. Full sequences of each 147-amino acid globin were achieved with a high degree of confidence using standard Edman technology in combination with molecular mass determinations of the intact globins and of the cyanogen bromide cleavage fragments using electrospray ionization mass spectrometry. When minor assumptions concerning Q/E identities are made these new results indicate the likely correspondence of GMG2 with the protein represented by the first Glycera dibranchiata monomer hemoglobin complete sequence [Imamura et al., (1972), J. Biol. Chem. 247, 2785–2797]. When these new sequences are combined with the previously determined primary sequence for the third major monomer hemoglobin, GMH4 [Alam et al., J. Protein Chem. (1994), 13, 151–164], it becomes clear that these three (GMG2–4) are truly distinct proteins, contrary to previous suggestions. Surprisingly, our results show that none of these three primary sequences is identical to the published sequence of the refined monomer hemoglobin crystal structure protein; however, there is a strong correspondence to the GMG2 sequence. The present sequencing results, in combination with the published GMH4 sequence, confirm the presence of a distal Leu in place of the more commonly encountered distal His in all three of the major monomer hemoglobins isolated in this laboratory and indicate that the unusual B10 Phe occurs only in GMH4. Analysis of the sequences presented here, along with comparison of amino acid content for Glycera dibranchiata monomer hemoglobins isolated from three different laboratories, and comparison of NMR results from two laboratories suggest further correspondences which unify disparate published isolations.  相似文献   
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