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1.
Diabetes Care ; 46(3): 519-525, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36542537

RESUMO

OBJECTIVE: The aim of this study was to describe cross-sectional and longitudinal associations between glycated hemoglobin (HbA1c) levels and strategies to control type 2 diabetes with baseline levels and 8-year changes in a deficit accumulation frailty index (FI), a commonly used marker of biological aging. RESEARCH DESIGN AND METHODS: We conducted exploratory analyses from 4,169 participants, aged 45-76 years, who were followed in the Action for Health in Diabetes (Look AHEAD) randomized controlled clinical trial, pooling data across intervention groups. We related baseline and 8-year levels of HbA1c with FI scores using analyses of variance and covariance. Associations between 8-year changes in FI and the use of diabetes medication classes and weight changes were assessed with control for HbA1c levels. Inverse probability weighting was used to assess bias associated with differential follow-up. RESULTS: Baseline and average HbA1c levels over time of <7%, as compared with ≥8%, were associated with less increase in FI scores over 8 years (both P ≤ 0.002). After adjustment for HbA1c, use of metformin and weight loss >5% were independently associated with slower increases in frailty. CONCLUSIONS: Lower HbA1c levels among individuals with diabetes are associated with slower biological aging as captured by a deficit accumulation FI. Strategies to control diabetes through weight loss or metformin use may also slow aging.


Assuntos
Diabetes Mellitus Tipo 2 , Fragilidade , Metformina , Humanos , Diabetes Mellitus Tipo 2/complicações , Hemoglobinas Glicadas , Fragilidade/complicações , Estudos Transversais , Metformina/uso terapêutico , Redução de Peso
2.
Surgery ; 173(3): 732-738, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36280511

RESUMO

BACKGROUND: Although ventral hernias are common in older adults and can impair quality of life, multiple barriers exist that preclude ventral hernia repair. The goal of this study was to determine if older adults with ventral hernias achieve surgeon-directed goals to progress to an elective ventral hernia repair. METHODS: Patients ≥60 years evaluated for a ventral hernia in a specialty clinic from January 2018 to August 2021 were retrospectively reviewed. Nonoperative candidates with modifiable risk factors were included. Data collected included specific barriers to ventral hernia repair and recommendations to address these barriers for future ventral hernia repair eligibility. Patients lost to follow-up were contacted by phone. RESULTS: In total, 559 patients were evaluated, with 182 (32.6%) deemed nonoperative candidates with modifiable risk factors (median age 68 years, body mass index 38.2). Surgeon-directed recommendations included weight loss (53.8%), comorbidity management by a medical specialist (44.0%), and smoking cessation (19.2%). Ultimately, 45/182 patients (24.7%) met preoperative goals and progressed to elective ventral hernia repair. Alternatively, 5 patients (2.7%) required urgent/emergency surgical intervention. Importantly, 106/182 patients (58.2%) did not return to clinic after initial consultation. Of those contacted (n = 62), 35.5% reported failure to achieve optimization goals. Initial body mass index ≥40 and surgeon-recommended weight loss were associated with lack of patient follow-up (P = .01, P = .02) and progression to elective ventral hernia repair (P = .009, P = .005). CONCLUSION: Nearly one-third of older adults evaluated for ventral hernias were nonoperative candidates, most often due to obesity, and over half of these patients were lost to follow-up. An increase in structured support is needed for patients to achieve surgeon-specified preoperative goals.


Assuntos
Hérnia Ventral , Herniorrafia , Humanos , Idoso , Estudos Retrospectivos , Herniorrafia/efeitos adversos , Qualidade de Vida , Objetivos , Hérnia Ventral/cirurgia , Hérnia Ventral/etiologia
4.
Oncotarget ; 9(43): 27117-27132, 2018 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-29930755

RESUMO

The glycosylated protein vasorin physically interacts with the transforming growth factor-beta1 (TGF-ß1) and functionally attenuates its fibrogenic signaling in the vascular smooth muscle cells (VSMCs) of the arterial wall. Angiotensin II (Ang II) amplifies TGF-ß1 activation in the VSMCs of the arterial wall with aging. In this study, we hypothesized that a reduced expression of the protein vasorin plays a contributory role in magnifying Ang II-associated fibrogenic signaling in the VSMCs of the arterial wall with aging. The current study shows that vasorin mRNA and protein expression were significantly decreased both in aortic wall and VSMCs from old (30 mo) vs. young (8 mo) FXBN rats. Exposing young VSMCs to Ang II reduced vasorin protein expression to the levels of old untreated cells while treating old VSMCs with the Ang II type AT1 receptor antagonist Losartan upregulated vasorin protein expression up to the levels of young. The physical interaction between vasorin and TGF-ß1 was significantly decreased in old vs. young VSMCs. Further, exposing young VSMCs to Ang II increased the levels of matrix metalloproteinase type II (MMP-2) activation and TGF-ß1 downstream molecules p-SMAD-2/3 and collagen type I production up to the levels of old untreated VSMCs, and these effects were substantially inhibited by overexpressing vasorin. Administration of Ang II to young rats (8 mo) for 28 days via an osmotic minipump markedly reduced the expression of vasorin. Importantly, vasorin protein was effectively cleaved by activated MMP-2 both in vitro and in vivo. Administration of the MMP inhibitor, PD 166793, for 6 mo to young adult (18 mo) via a daily gavage markedly increased levels of vasorin in the aortic wall. Thus, reduced vasorin amplifies Ang II profibrotic signaling via an activation of MMP-2 in VSMCs within the aging arterial wall.

5.
J Photochem Photobiol B ; 185: 161-168, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29936409

RESUMO

The unique properties of chlorosomes, arising out of the self-assembled bateriochlorophyll (BChl) c structure, have made them attractive for use in solar cells. In this work, we have demonstrated the self-assembly of BChl c in aerosolized droplets to mimic naturally occurring chlorosomes. We compare two different methods for self-assembly of BChl c, one using a single-solvent and the other using two-solvents, and demonstrate the superiority of the two-solvent method. Results show that the self-assembled BChl c sprayed at different concentrations resulted in a varying red shift of 69-75 nm in absorption spectrum compared to the solution, which has peak at 668 nm corresponding to the monomeric BChl c. The sample fluoresces at 780 nm indicating a quality of self-assembly comparable to that observed in naturally occurring chlorosomes. In order to mimic chlorosomes, solution containing BChl c, BChl a, lipids and carotenes in same proportion as in chlorosomes is sprayed. The resulting self-assembly has an absorption peak at 750 nm, shifted by 82 nm compared to that of monomers and the fluorescence peak at 790 nm. Thus in presence of lipids and carotenes, both the absorption and fluorescence peaks are red shifted. Further, using grazing incidence small angle X-ray scattering (GISAXS), we characterized the deposited films, and the 2D X-ray scattering patterns of sample clearly indicate the distinct lamellar structure as present in chlorosomes. The results of this work provide new insights into self-assembly in aerosolized droplets, which can be used for assembling a wide range of molecules.


Assuntos
Proteínas de Bactérias/biossíntese , Bacterioclorofilas/metabolismo , Biomimética , Gotículas Lipídicas/química , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Bacterioclorofilas/química , Carotenoides/química , Chlorobi/metabolismo , Espalhamento a Baixo Ângulo , Solventes/química , Espectrometria de Fluorescência , Difração de Raios X
6.
J Immunol ; 197(3): 726-35, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27324129

RESUMO

Osteoimmunology arose from the recognition that cytokines produced by lymphocytes can affect bone homeostasis. We have previously shown that osteoclasts, cells that resorb bone, act as APCs. Cross-presentation of Ags by osteoclasts leads to expression of CD25 and Foxp3, markers of regulatory T cells in the CD8 T cells. Octeoclast-induced Foxp3(+) CD25(+) regulatory CD8 T cells (OC-iTcREG) suppress priming of CD4 and CD8 T cells by dendritic cells. OC-iTcREG also limit bone resorption by osteoclasts, forming a negative feedback loop. In this study, we show that OC-iTcREG express concurrently T-bet and Eomesodermin (Eomes) and IFN-γ. Pharmacological inhibition of IκK blocked IFN-γ, T-bet, and Eomes production by TcREG Furthermore, we show, using chromatin immunoprecipitation, NF-κB enrichment in the T-bet and Eomes promoters. We demonstrate that IFN-γ produced by TcREG is required for suppression of osteoclastogenesis and for degradation of TNFR-associated factor 6 in osteoclast precursors. The latter prevents signaling by receptor activator of NF-κB ligand needed for osteoclastogenesis. Knockout of IFN-γ rendered TcREG inefficient in preventing actin ring formation in osteoclasts, a process required for bone resorption. TcREG generated in vivo using IFN-γ(-/-) T cells had impaired ability to protect mice from bone resorption and bone loss in response to high-dose receptor activator of NF-κB ligand. The results of this study demonstrate a novel link between NF-κB signaling and induction of IFN-γ in TcREG and establish an important role for IFN-γ in TcREG-mediated protection from bone loss.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Reabsorção Óssea/imunologia , Linfócitos T CD8-Positivos/imunologia , Interferon gama/imunologia , Osteoclastos/imunologia , Animais , Apresentação de Antígeno/imunologia , Western Blotting , Diferenciação Celular/imunologia , Imunoprecipitação da Cromatina , Citometria de Fluxo , Fatores de Transcrição Forkhead/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/imunologia , NF-kappa B/metabolismo , Osteogênese/fisiologia , Reação em Cadeia da Polimerase , Transdução de Sinais/imunologia , Proteínas com Domínio T/biossíntese , Proteínas com Domínio T/imunologia
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