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1.
Nature ; 629(8013): 869-877, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38693267

RESUMEN

Airway hillocks are stratified epithelial structures of unknown function1. Hillocks persist for months and have a unique population of basal stem cells that express genes associated with barrier function and cell adhesion. Hillock basal stem cells continually replenish overlying squamous barrier cells. They exhibit dramatically higher turnover than the abundant, largely quiescent classic pseudostratified airway epithelium. Hillocks resist a remarkably broad spectrum of injuries, including toxins, infection, acid and physical injury because hillock squamous cells shield underlying hillock basal stem cells from injury. Hillock basal stem cells are capable of massive clonal expansion that is sufficient to resurface denuded airway, and eventually regenerate normal airway epithelium with each of its six component cell types. Hillock basal stem cells preferentially stratify and keratinize in the setting of retinoic acid signalling inhibition, a known cause of squamous metaplasia2,3. Here we show that mouse hillock expansion is the cause of vitamin A deficiency-induced squamous metaplasia. Finally, we identify human hillocks whose basal stem cells generate functional squamous barrier structures in culture. The existence of hillocks reframes our understanding of airway epithelial regeneration. Furthermore, we show that hillocks are one origin of 'squamous metaplasia', which is long thought to be a precursor of lung cancer.


Asunto(s)
Plasticidad de la Célula , Células Epiteliales , Regeneración , Mucosa Respiratoria , Células Madre , Animales , Femenino , Humanos , Masculino , Ratones , Células Epiteliales/citología , Células Epiteliales/patología , Metaplasia/etiología , Metaplasia/patología , Mucosa Respiratoria/citología , Mucosa Respiratoria/lesiones , Mucosa Respiratoria/patología , Células Madre/citología , Tretinoina/metabolismo , Tretinoina/farmacología , Vitamina A/metabolismo , Vitamina A/farmacología , Neoplasias Pulmonares/etiología , Neoplasias Pulmonares/patología , Ratones Endogámicos C57BL
2.
N Engl J Med ; 387(13): 1161-1172, 2022 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-36170500

RESUMEN

BACKGROUND: Currently available semiautomated insulin-delivery systems require individualized insulin regimens for the initialization of therapy and meal doses based on carbohydrate counting for routine operation. In contrast, the bionic pancreas is initialized only on the basis of body weight, makes all dose decisions and delivers insulin autonomously, and uses meal announcements without carbohydrate counting. METHODS: In this 13-week, multicenter, randomized trial, we randomly assigned in a 2:1 ratio persons at least 6 years of age with type 1 diabetes either to receive bionic pancreas treatment with insulin aspart or insulin lispro or to receive standard care (defined as any insulin-delivery method with unblinded, real-time continuous glucose monitoring). The primary outcome was the glycated hemoglobin level at 13 weeks. The key secondary outcome was the percentage of time that the glucose level as assessed by continuous glucose monitoring was below 54 mg per deciliter; the prespecified noninferiority limit for this outcome was 1 percentage point. Safety was also assessed. RESULTS: A total of 219 participants 6 to 79 years of age were assigned to the bionic-pancreas group, and 107 to the standard-care group. The glycated hemoglobin level decreased from 7.9% to 7.3% in the bionic-pancreas group and did not change (was at 7.7% at both time points) in the standard-care group (mean adjusted difference at 13 weeks, -0.5 percentage points; 95% confidence interval [CI], -0.6 to -0.3; P<0.001). The percentage of time that the glucose level as assessed by continuous glucose monitoring was below 54 mg per deciliter did not differ significantly between the two groups (13-week adjusted difference, 0.0 percentage points; 95% CI, -0.1 to 0.04; P<0.001 for noninferiority). The rate of severe hypoglycemia was 17.7 events per 100 participant-years in the bionic-pancreas group and 10.8 events per 100 participant-years in the standard-care group (P = 0.39). No episodes of diabetic ketoacidosis occurred in either group. CONCLUSIONS: In this 13-week, randomized trial involving adults and children with type 1 diabetes, use of a bionic pancreas was associated with a greater reduction than standard care in the glycated hemoglobin level. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others; ClinicalTrials.gov number, NCT04200313.).


Asunto(s)
Diabetes Mellitus Tipo 1 , Hipoglucemiantes , Insulina Aspart , Sistemas de Infusión de Insulina , Insulina Lispro , Adolescente , Adulto , Anciano , Biónica/instrumentación , Glucemia/análisis , Automonitorización de la Glucosa Sanguínea/instrumentación , Automonitorización de la Glucosa Sanguínea/métodos , Niño , Diabetes Mellitus Tipo 1/sangre , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hemoglobina Glucada/análisis , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/efectos adversos , Hipoglucemiantes/uso terapéutico , Insulina/administración & dosificación , Insulina/efectos adversos , Insulina/uso terapéutico , Insulina Aspart/administración & dosificación , Insulina Aspart/efectos adversos , Insulina Aspart/uso terapéutico , Sistemas de Infusión de Insulina/efectos adversos , Insulina Lispro/administración & dosificación , Insulina Lispro/efectos adversos , Insulina Lispro/uso terapéutico , Persona de Mediana Edad , Adulto Joven
3.
Nature ; 567(7748): 405-408, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30867598

RESUMEN

Loss-of-function mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) compromise epithelial HCO3- and Cl- secretion, reduce airway surface liquid pH, and impair respiratory host defences in people with cystic fibrosis1-3. Here we report that apical addition of amphotericin B, a small molecule that forms unselective ion channels, restored HCO3- secretion and increased airway surface liquid pH in cultured airway epithelia from people with cystic fibrosis. These effects required the basolateral Na+, K+-ATPase, indicating that apical amphotericin B channels functionally interfaced with this driver of anion secretion. Amphotericin B also restored airway surface liquid pH, viscosity, and antibacterial activity in primary cultures of airway epithelia from people with cystic fibrosis caused by different mutations, including ones that do not yield CFTR, and increased airway surface liquid pH in CFTR-null pigs in vivo. Thus, unselective small-molecule ion channels can restore host defences in cystic fibrosis airway epithelia via a mechanism that is independent of CFTR and is therefore independent of genotype.


Asunto(s)
Fibrosis Quística/metabolismo , Epitelio/metabolismo , Canales Iónicos/metabolismo , Mucosa Respiratoria/metabolismo , Sistema Respiratorio/metabolismo , Anfotericina B/farmacología , Animales , Bicarbonatos/metabolismo , Células Cultivadas , Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/deficiencia , Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Regulador de Conductancia de Transmembrana de Fibrosis Quística/metabolismo , Células Epiteliales/citología , Células Epiteliales/efectos de los fármacos , Células Epiteliales/metabolismo , Epitelio/efectos de los fármacos , Femenino , Humanos , Concentración de Iones de Hidrógeno , Masculino , Mucosa Respiratoria/efectos de los fármacos , Sistema Respiratorio/efectos de los fármacos , ATPasa Intercambiadora de Sodio-Potasio/metabolismo , Porcinos
4.
Diabetes Obes Metab ; 26(2): 540-547, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37880868

RESUMEN

AIM: To assess whether multiple switches between SAR341402 biosimilar insulin aspart (SAR-Asp) and the insulin aspart reference product (NovoLog; NN-Asp) leads to equivalent pharmacokinetic (PK) exposure compared with continuous use of NN-Asp in adults with type 1 diabetes (T1D). MATERIALS AND METHODS: This multicentre, open-label, phase 3 study randomized (1:1) 210 subjects with T1D treated with once-daily insulin glargine U100 as basal insulin to four 4-week periods of alternating multiple daily injections of SAR-Asp and NN-Asp (NN-Asp for the first 4 weeks, SAR-Asp in the last 4 weeks; switching group) versus 16 weeks of continuous NN-Asp (non-switching group). At week 16, a single dose (0.15 U/kg) of SAR-Asp in the switching group (n = 95) or NN-Asp in the non-switching group (n = 105) was given in the morning before breakfast. Primary PK endpoints were area under the plasma concentration curve (AUC) and maximum plasma concentration (Cmax ) of SAR-Asp versus NN-Asp after the single dose at week 16. RESULTS: The extent of PK exposure was similar between the two treatments (SAR-Asp in the switching group and NN-Asp in the non-switching group) at week 16, with point estimates of treatment ratios close to 1. The 90% confidence intervals for AUC treatment ratios were contained within 0.8-1.25. For Cmax in the primary analysis set, the upper confidence limit was 1.32. This was because of the profiles of three participants with implausible high values. A prespecified sensitivity analysis excluding implausible values showed results contained within 0.8-1.25. CONCLUSIONS: PK exposure of SAR-Asp (switching group) and reference NN-Asp (non-switching group) were similar, supporting interchangeability between these two insulin aspart products.


Asunto(s)
Biosimilares Farmacéuticos , Diabetes Mellitus Tipo 1 , Adulto , Humanos , Biosimilares Farmacéuticos/administración & dosificación , Biosimilares Farmacéuticos/farmacocinética , Glucemia , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/farmacocinética , Insulina/farmacocinética , Insulina Aspart/farmacocinética , Insulina Glargina/farmacocinética
5.
Environ Sci Technol ; 58(22): 9760-9769, 2024 Jun 04.
Artículo en Inglés | MEDLINE | ID: mdl-38775357

RESUMEN

Peroxyacetyl nitrate (PAN) is produced in the atmosphere by photochemical oxidation of non-methane volatile organic compounds in the presence of nitrogen oxides (NOx), and it can be transported over long distances at cold temperatures before decomposing thermally to release NOx in the remote troposphere. It is both a tracer and a precursor for transpacific ozone pollution transported from East Asia to North America. Here, we directly demonstrate this transport with PAN satellite observations from the infrared atmospheric sounding interferometer (IASI). We reprocess the IASI PAN retrievals by replacing the constant prior vertical profile with vertical shape factors from the GEOS-Chem model that capture the contrasting shapes observed from aircraft over South Korea (KORUS-AQ) and the North Pacific (ATom). The reprocessed IASI PAN observations show maximum transpacific transport of East Asian pollution in spring, with events over the Northeast Pacific offshore from the Western US associated in GEOS-Chem with elevated ozone in the lower free troposphere. However, these events increase surface ozone in the US by less than 1 ppbv because the East Asian pollution mainly remains offshore as it circulates the Pacific High.


Asunto(s)
Ozono , Ozono/química , Atmósfera/química , Contaminantes Atmosféricos , Monitoreo del Ambiente
6.
Diabetes Obes Metab ; 25(11): 3144-3151, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37427768

RESUMEN

AIM: To evaluate the glycaemia risk index (GRI) and its association with other continuous glucose monitoring (CGM) metrics after initiation of an automated insulin delivery (AID) system in patients with type 1 diabetes (T1D). MATERIALS AND METHODS: Up to 90 days of CGM data before and after initiation of an AID system from 185 CGM users with T1D were collected. GRI and other CGM metrics were calculated using cgmanalysis R software and were analysed for 24 hours, for both night-time and daytime. GRI values were assigned to five GRI zones: zone A (0-20), B (21-40), C (41-60), D (61-80) and E (81-100). RESULTS: Compared with baseline, GRI and its components decreased significantly after AID initiation (GRI: 48.7 ± 21.8 vs. 29 ± 13; hypoglycaemia component: 2.7 ± 2.8 vs. 1.6 ± 1.7; hyperglycaemia component: 25.3 ± 14.5 vs. 15 ± 8.5; P < .001 for all). The GRI was inversely correlated with time in range before (r = -0.962) and after (r = -0.961) AID initiation (P < .001 for both). GRI was correlated with time above range (before: r = 0.906; after = 0.910; P < .001 for both), but not with time below range (P > .05). All CGM metrics improved after AID initiation during 24 hours, for both daytime and night-time (P < .001 for all). Metrics improved significantly more during night-time than daytime (P < .01). CONCLUSIONS: GRI was highly correlated with various CGM metrics above, but not below target range, both before and after AID initiation.


Asunto(s)
Diabetes Mellitus Tipo 1 , Hipoglucemia , Humanos , Adulto , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Glucemia , Insulina/efectos adversos , Automonitorización de la Glucosa Sanguínea , Hipoglucemia/inducido químicamente , Hipoglucemia/epidemiología , Hipoglucemia/prevención & control , Hipoglucemiantes/efectos adversos
7.
BMC Endocr Disord ; 23(1): 147, 2023 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-37430302

RESUMEN

BACKGROUND: To evaluate use of low-calorie sweeteners (LCS) among adults with type 1 diabetes (T1D) and its impact on quality of life (QOL). METHODS: In this single center, cross-sectional survey study with 532 adults with T1D, Food related QOL (FRQOL), LCS specific questionnaire (LCSSQ), Diabetes Self-Management Questionnaire (DSMQ), Food Frequency Questionnaire (FFQ), Audit of Diabetes-Dependent QOL (AddQOL), Type 1 Diabetes and Life (T1DAL) questionnaires were administered through RedCAP, a secure, HIPAA-compliant web-based application. Demographics and scores of adults who used LCS in last month (recent users) and others (non-users) were compared. Results were adjusted for age, sex, diabetes duration and other parameters. RESULTS: Of 532 participants (mean age 36 ± 13, 69% female), 99% heard LCS before, 68% used them in the last month, 73% reported better glucose control with LCS use and 63% reported no health concerns about LCS use. Recent LCS users were older and had a longer diabetes duration and more complications (hypertension, or any complication) than non-users. However, A1c, AddQOL, T1DAL, FRQOL scores did not differ significantly between recent LCS users and non-users. DSMQ scores, DSMQ management, diet, health care scores did not differ between two groups; however, recent LCS users had lower physical activity score than non-users (p = 0.001). CONCLUSIONS: Most of the adults with T1D have used LCS and perceived that LCS use improved their QOL and glycemic control; however, these were not verified with questionnaires. There was no difference in QOL questionnaires except DSMQ physical activity between recent LCS users and not users with T1D. However, more patients in need to increase their QOL may be using LCS; therefore, associations between the exposure and outcome can be bi-directional.


Asunto(s)
Diabetes Mellitus Tipo 1 , Calidad de Vida , Edulcorantes , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Estudios Transversales , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/psicología , Ingestión de Energía , Conductas Relacionadas con la Salud , Edulcorantes/administración & dosificación , Edulcorantes/efectos adversos
8.
Clin Diabetes ; 41(3): 386-398, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37456091

RESUMEN

Despite evidence of improved diabetes outcomes with diabetes technology such as continuous glucose monitoring (CGM) systems, insulin pumps, and hybrid closed-loop (HCL) insulin delivery systems, these devices are underutilized in clinical practice for the management of insulin-requiring diabetes. This low uptake may be the result of health care providers' (HCPs') lack of confidence or time to prescribe and manage devices for people with diabetes. We administered a survey to HCPs in primary care, pediatric endocrinology, and adult endocrinology practices in the United States. Responding HCPs expressed a need for device-related insurance coverage tools and online data platforms with integration to electronic health record systems to improve diabetes technology uptake in these practice settings across the United States.

9.
Diabet Med ; 39(8): e14854, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35441743

RESUMEN

AIMS: We aimed to conduct a systematic review and meta-analysis of randomised controlled clinical trials (RCTs) assessing separately and together the effect of the three distinct categories of continuous glucose monitoring (CGM) systems (adjunctive, non-adjunctive and intermittently-scanned CGM [isCGM]), compared with traditional capillary glucose monitoring, on HbA1c and CGM metrics. METHODS: PubMed, Web of Science, Scopus and Cochrane Central register of clinical trials were searched. Inclusion criteria were as follows: randomised controlled trials; participants with type 1 diabetes of any age and insulin regimen; investigating CGM and isCGM compared with traditional capillary glucose monitoring; and reporting glycaemic outcomes of HbA1c and/or time-in-range (TIR). Glycaemic outcomes were extracted post-intervention and expressed as mean differences and 95%CIs between treatment and comparator groups. Results were pooled using a random-effects meta-analysis. Risk of bias was assessed using the Cochrane Rob2 tool. RESULTS: This systematic review was conducted between January and April 2021; it included 22 RCTs (15 adjunctive, 5 non-adjunctive, and 2 isCGM)). The overall analysis of the pooled three categories showed a statistically significant absolute improvement in HbA1c percentage points (mean difference (95% CI): -0.22% [-0.31 to -0.14], I2  = 79%) for intervention compared with comparator and was strongest for adjunctive CGM (-0.26% [-0.36, -0.16]). Overall TIR (absolute change) increased by 5.4% (3.5 to 7.2), I2  = 71% for CGM intervention compared with comparator and was strongest with non-adjunctive CGM (6.0% [2.3, 9.7]). CONCLUSIONS: For individuals with T1D, use of CGM was beneficial for impacting glycaemic outcomes including HbA1c, TIR and time-below-range (TBR). Glycaemic improvement appeared greater for TIR for newer non-adjunctive CGM technology.


Asunto(s)
Diabetes Mellitus Tipo 1 , Glucemia/análisis , Automonitorización de la Glucosa Sanguínea/métodos , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hemoglobina Glucada/análisis , Control Glucémico , Humanos , Hipoglucemiantes/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Tecnología
10.
AAPS PharmSciTech ; 23(5): 120, 2022 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-35460024

RESUMEN

Controlled release dosage forms maintain regulated pharmacokinetic profile of drug substance within its therapeutic window by ensuring constant plasma concentrations. Controlled release formulations not only increase the therapeutic efficacy of drug substances but also reduce their dose-related side effects. Present investigation was conducted to develop, optimize, and validate compressed coated controlled release tablet formulation for highly water-soluble drug substances which have no rate-controlling factor towards its release from dosage form. Drug dispersed waxy core tablet, press coated within the swellable hydrophilic polymeric barrier layer, was developed and optimized via quality by design approach (QbD) using Box-Behnken design. The optimized formulation was characterized and validated using in vitro quality control parameters. Attributes identified under SUPAC guidelines, such as drug release rates at 30 min, 6 h, and 12 h, were considered as the critical quality attributes (CQAs) that significantly affected efficiency of the compressed coated controlled release tablets. CQAs screened using risk assessment and Pareto chart analyses were used for optimizing controlled release dosage form. Findings revealed that tablets containing drug to wax ratio of 1:1, hydrophilic swellable polymer concentration of 200 mg, and prepared using compression pressure of 6.5 kg/cm2 exhibited the highest desirability indices in terms of controlling the release rate of drug substance. Optimized formulation was also evaluated for swelling rate, erosion rate, and other post-compression parameters, including release kinetics. Fickian diffusion-based zero-order controlled release of BCS class I drug substance was achieved through the developed dosage form.


Asunto(s)
Polímeros , Agua , Preparaciones de Acción Retardada , Liberación de Fármacos , Comprimidos
11.
Blood ; 133(21): 2305-2319, 2019 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-30814062

RESUMEN

Neural cell adhesion molecule 1 (NCAM1; CD56) is expressed in up to 20% of acute myeloid leukemia (AML) patients. NCAM1 is widely used as a marker of minimal residual disease; however, the biological function of NCAM1 in AML remains elusive. In this study, we investigated the impact of NCAM1 expression on leukemogenesis, drug resistance, and its role as a biomarker to guide therapy. Beside t(8;21) leukemia, NCAM1 expression was found in most molecular AML subgroups at highly heterogeneous expression levels. Using complementary genetic strategies, we demonstrated an essential role of NCAM1 in the regulation of cell survival and stress resistance. Perturbation of NCAM1 induced cell death or differentiation and sensitized leukemic blasts toward genotoxic agents in vitro and in vivo. Furthermore, Ncam1 was highly expressed in leukemic progenitor cells in a murine leukemia model, and genetic depletion of Ncam1 prolonged disease latency and significantly reduced leukemia-initiating cells upon serial transplantation. To further analyze the mechanism of the NCAM1-associated phenotype, we performed phosphoproteomics and transcriptomics in different AML cell lines. NCAM1 expression strongly associated with constitutive activation of the MAPK-signaling pathway, regulation of apoptosis, or glycolysis. Pharmacological inhibition of MEK1/2 specifically inhibited proliferation and sensitized NCAM1+ AML cells to chemotherapy. In summary, our data demonstrate that aberrant expression of NCAM1 is involved in the maintenance of leukemic stem cells and confers stress resistance, likely due to activation of the MAPK pathway. Targeting MEK1/2 sensitizes AML blasts to genotoxic agents, indicating a role for NCAM1 as a biomarker to guide AML treatment.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Crisis Blástica/metabolismo , Antígeno CD56/metabolismo , Resistencia a Antineoplásicos , Leucemia Mieloide Aguda/metabolismo , Proteínas de Neoplasias/metabolismo , Animales , Apoptosis/genética , Biomarcadores de Tumor/genética , Crisis Blástica/genética , Crisis Blástica/patología , Crisis Blástica/terapia , Antígeno CD56/genética , Femenino , Glucólisis/genética , Células HL-60 , Humanos , Células K562 , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Leucemia Mieloide Aguda/terapia , Sistema de Señalización de MAP Quinasas/genética , Masculino , Ratones , Ratones Endogámicos NOD , Ratones Noqueados , Proteínas de Neoplasias/genética
12.
Diabetes Obes Metab ; 23(8): 1936-1941, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34180122

RESUMEN

AIM: To evaluate two methods of transition from an insulin pump to multiple daily injections (MDI) using long-acting insulin degludec (IDeg). MATERIALS AND METHODS: After a 1-week run-in period, adults with type 1 diabetes for longer than 1 year and HbA1c 48-69 mmol/mol (6.5%-8.5%), who had been using an insulin pump at least for 6 months, were randomly transitioned to either standard of care (discontinued insulin pump and started IDeg in 1:1 dose) or overlap (IDeg 1:1 at pump basal dose, but pump continued for the first 48 hours with a gradual basal reduction; 50% from 0-24 hours, 75% from 24-48 hours and then pump discontinued). Participants used blinded Dexcom G6 and the IDeg dose was not changed during the trial. Primary (% time above 180 mg/dL) and secondary (% time in 70-180 mg/dL and below 70 mg/dL) outcomes were compared between the two groups during 7 days of randomization. RESULTS: Age, gender, diabetes duration and basal/bolus insulin doses were similar between patients randomized to standard of care (n = 17) or overlap (n = 13) transition. Compared with overlap transition, the standard of care group spent 4.8% more time in hyperglycaemia (least square mean 4.8% [95% CI -3.3%, 12.9%]) and 5.3% less time in range (-5.3% [-12.6%, -2.0%]), without a significant difference in hypoglycaemia (0.5% [-2.3%,3.4%]). No treatment-related adverse events were noted in either group. CONCLUSION: The overlap transition method may result in a significant improvement in time-in-range without increasing hypoglycaemia during the first week of transition from an insulin pump to MDI using IDeg in adults with type 1 diabetes.


Asunto(s)
Diabetes Mellitus Tipo 1 , Hipoglucemiantes , Adulto , Glucemia , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Hemoglobina Glucada/análisis , Humanos , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Sistemas de Infusión de Insulina , Insulina de Acción Prolongada/uso terapéutico
13.
Environ Sci Technol ; 55(21): 14445-14456, 2021 11 02.
Artículo en Inglés | MEDLINE | ID: mdl-34724789

RESUMEN

We present a new chemical mechanism for Hg0/HgI/HgII atmospheric cycling, including recent laboratory and computational data, and implement it in the GEOS-Chem global atmospheric chemistry model for comparison to observations. Our mechanism includes the oxidation of Hg0 by Br and OH, subsequent oxidation of HgI by ozone and radicals, respeciation of HgII in aerosols and cloud droplets, and speciated HgII photolysis in the gas and aqueous phases. The tropospheric Hg lifetime against deposition in the model is 5.5 months, consistent with observational constraints. The model reproduces the observed global surface Hg0 concentrations and HgII wet deposition fluxes. Br and OH make comparable contributions to global net oxidation of Hg0 to HgII. Ozone is the principal HgI oxidant, enabling the efficient oxidation of Hg0 to HgII by OH. BrHgIIOH and HgII(OH)2, the initial HgII products of Hg0 oxidation, respeciate in aerosols and clouds to organic and inorganic complexes, and volatilize to photostable forms. Reduction of HgII to Hg0 takes place largely through photolysis of aqueous HgII-organic complexes. 71% of model HgII deposition is to the oceans. Major uncertainties for atmospheric Hg chemistry modeling include Br concentrations, stability and reactions of HgI, and speciation and photoreduction of HgII in aerosols and clouds.


Asunto(s)
Mercurio , Aerosoles , Monitoreo del Ambiente , Mercurio/análisis , Océanos y Mares , Oxidación-Reducción , Agua
14.
Geophys Res Lett ; 48(10): e2021GL092783, 2021 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-34149109

RESUMEN

Satellite nitrogen dioxide (NO2) measurements are used extensively to infer nitrogen oxide emissions and their trends, but interpretation can be complicated by background contributions to the NO2 column sensed from space. We use the step decrease of US anthropogenic emissions from the COVID-19 shutdown to compare the responses of NO2 concentrations observed at surface network sites and from satellites (Ozone Monitoring Instrument [OMI], Tropospheric Ozone Monitoring Instrument [TROPOMI]). After correcting for differences in meteorology, surface NO2 measurements for 2020 show decreases of 20% in March-April and 10% in May-August compared to 2019. The satellites show much weaker responses in March-June and no decrease in July-August, consistent with a large background contribution to the NO2 column. Inspection of the long-term OMI trend over remote US regions shows a rising summertime NO2 background from 2010 to 2019 potentially attributable to wildfires.

15.
Proc Natl Acad Sci U S A ; 115(32): 8110-8115, 2018 08 07.
Artículo en Inglés | MEDLINE | ID: mdl-30037992

RESUMEN

Sulfate ([Formula: see text]) and nitrate ([Formula: see text]) account for half of the fine particulate matter mass over the eastern United States. Their wintertime concentrations have changed little in the past decade despite considerable precursor emissions reductions. The reasons for this have remained unclear because detailed observations to constrain the wintertime gas-particle chemical system have been lacking. We use extensive airborne observations over the eastern United States from the 2015 Wintertime Investigation of Transport, Emissions, and Reactivity (WINTER) campaign; ground-based observations; and the GEOS-Chem chemical transport model to determine the controls on winter [Formula: see text] and [Formula: see text] GEOS-Chem reproduces observed [Formula: see text]-[Formula: see text]-[Formula: see text] particulate concentrations (2.45 µg [Formula: see text]) and composition ([Formula: see text]: 47%; [Formula: see text]: 32%; [Formula: see text]: 21%) during WINTER. Only 18% of [Formula: see text] emissions were regionally oxidized to [Formula: see text] during WINTER, limited by low [H2O2] and [OH]. Relatively acidic fine particulates (pH∼1.3) allow 45% of nitrate to partition to the particle phase. Using GEOS-Chem, we examine the impact of the 58% decrease in winter [Formula: see text] emissions from 2007 to 2015 and find that the H2O2 limitation on [Formula: see text] oxidation weakened, which increased the fraction of [Formula: see text] emissions oxidizing to [Formula: see text] Simultaneously, NOx emissions decreased by 35%, but the modeled [Formula: see text] particle fraction increased as fine particle acidity decreased. These feedbacks resulted in a 40% decrease of modeled [[Formula: see text]] and no change in [[Formula: see text]], as observed. Wintertime [[Formula: see text]] and [[Formula: see text]] are expected to change slowly between 2015 and 2023, unless [Formula: see text] and NOx emissions decrease faster in the future than in the recent past.

16.
J Assoc Physicians India ; 69(2): 71-72, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33527819

RESUMEN

Fungi in the class of zygomycetes usually produce serious infections in diabetics and immunocompromised hosts. Cutaneous zygomycosis is a less common form, with an unpredictable extent of anatomical involvement and clinical course1.¹ Here, we report a case of primary cutaneous zygomycosis caused by saksaenea vasiformis as posttraumatic complications in a diabetic female. Zygomycosis was suspected and specimens from the surgical debridement were examined by microbiological and histopathological studies for conforming the clinical diagnosis. Rapid diagnosis, liposomal amphotericin B, and proper debridement of affected tissue are necessary to avoid a fatal outcome.


Asunto(s)
Dermatomicosis , Diabetes Mellitus , Cigomicosis , Antifúngicos/uso terapéutico , Dermatomicosis/diagnóstico , Dermatomicosis/tratamiento farmacológico , Diabetes Mellitus/tratamiento farmacológico , Femenino , Hongos , Humanos , Huésped Inmunocomprometido , Cigomicosis/diagnóstico
17.
AAPS PharmSciTech ; 22(3): 118, 2021 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-33782790

RESUMEN

The present study was designed to develop an efficient, safe, and patient-friendly dosage form, for oral delivery of alfa-choriogonadotropin, used in the treatment of female reproductive infertility. Silica-coated, saturated fatty acid (dipalmitoylphosphatidylcholine (DPPC))-engineered, nanolipidic vesicular (NLVs) system was developed for systemic delivery of therapeutic peptide, alfa-choriogonadotropin, through oral route. DPPC-based NLVs were formulated using the technique of thin-film hydration and were coated with silica to form a homogeneous surface silica shell. The formulated silica-coated NLVs were evaluated for physicochemical and physiologic stability under simulated conditions and were optimized based on physicochemical parameters like particle size, zeta potential, polydispersity index (PDI), entrapment efficiency, and in vitro release profile. Silica-coated, DPPC-based NLVs imparted physicochemical stability to entrapped alfa-choriogonadotropin against the biological environment prevailing in the human gastrointestinal tract (GIT). In vivo, subchronic animal toxicity studies were performed to assess the safety of the designed dosage form. Results of in vitro characterization and in vivo pharmacokinetic studies of fabricated formulation revealed that the silica-coated, DPPC-based NLV formulation was not only stable in human GIT but was also as efficacious as a marketed parenteral formulation for the systemic delivery of alfa-choriogonadotropin. In vivo toxicity studies revealed that silica-coated NLVs did not alter hematological and serum biochemical parameters. The histopathological studies also depicted no macroscopic changes in major organs; thus, the developed formulation was proven to be nontoxic and equally efficient as a marketed parenteral formulation for the delivery of alfa-choriogonadotropin with added benefits of possible self-medication, more patient acceptability, and no chances of infection.


Asunto(s)
Gonadotropina Coriónica/administración & dosificación , Gonadotropina Coriónica/química , Ácidos Grasos/química , Lípidos/química , Sustancias para el Control de la Reproducción/administración & dosificación , Sustancias para el Control de la Reproducción/química , Dióxido de Silicio/química , 1,2-Dipalmitoilfosfatidilcolina/química , Administración Oral , Animales , Gonadotropina Coriónica/toxicidad , Portadores de Fármacos , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Masculino , Tamaño de la Partícula , Ratas , Ratas Sprague-Dawley , Sustancias para el Control de la Reproducción/toxicidad
18.
Diabetes Obes Metab ; 22(9): 1577-1585, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32329127

RESUMEN

AIM: To examine the control of cardiovascular risk factors in type 1 diabetes (T1D) registries from the United States and Germany/Austria. MATERIALS AND METHODS: Data on individuals aged ≥12 years with T1D for ≥1 year, from the T1D Exchange Clinic Network (T1DX, United States) and the Prospective Diabetes Follow-up Registry (DPV, Germany/Austria) from 1 January 2016 to 31 March 2018 were analysed. Linear and logistic regression models adjusted for age groups, sex, duration of diabetes and minority status were used to compare clinical characteristics and achievement of diabetes management targets between registries. RESULTS: The cohort consisted of 47 936 patients (T1DX, n = 19 442; DPV, n = 28 494). Achievement of HbA1c goals (<7.0%, ages 18-65 years; all others, <7.5%) was better in the DPV for those aged <65 years (all P < .001). However, more older adults (aged ≥65 years) in the T1DX achieved an HbA1c goal of <7.5% compared with DPV (70% vs. 50%, P < .001). The frequency of patients with overweight (53% vs. 51%, P < .001) and obesity (19% vs. 9%, P < .001) was higher in T1DX. The frequency of meeting blood pressure goals (84% vs. 66%, P < .001) and lipid goals (73% vs. 62%, P < .001) was higher in T1DX; this was observed across all age groups (all P < .001). Few young adults aged <26 years received antihypertensive and lipid-lowering medications, respectively, despite indications in both registries (T1DX: 5% and 3%, DPV: 3% and 1%). CONCLUSION: A minority of patients with T1D achieve glycaemic targets and the majority are inadequately treated for hypertension and dyslipidaemia. This highlights the need for improved diabetes and cardiovascular risk management strategies in T1D.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 1 , Adolescente , Adulto , Anciano , Austria , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/epidemiología , Estudios de Seguimiento , Alemania/epidemiología , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Persona de Mediana Edad , Estudios Prospectivos , Sistema de Registros , Factores de Riesgo , Estados Unidos/epidemiología , Adulto Joven
19.
Curr Osteoporos Rep ; 18(4): 371-377, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32504189

RESUMEN

PURPOSE OF REVIEW: To provide an update on the acute effects of glucose, insulin, and incretins on markers of bone turnover in those with and without diabetes. RECENT FINDINGS: Bone resorption is suppressed acutely in response to glucose and insulin challenges in both healthy subjects and patients with diabetes. The suppression is stronger with oral glucose compared with intravenous delivery. Stronger responses with oral glucose may be related to incretin effects on insulin secretion or from a direct effect on bone turnover. Glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-2 (GLP-2) infusion acutely suppresses bone resorption without much effect on bone formation. The bone turnover response to a metabolic challenge may be attenuated in type 2 diabetes, but this is an understudied area. A knowledge gap exists regarding bone turnover responses to a metabolic challenge in type 1 diabetes. The gut-pancreas-bone link is potentially an endocrine axis. This linkage is disrupted in diabetes, but the mechanism and progression of this disruption are not understood.


Asunto(s)
Remodelación Ósea/fisiología , Resorción Ósea/metabolismo , Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Glucosa/metabolismo , Incretinas/metabolismo , Insulina/metabolismo , Osteogénesis/fisiología , Estudios de Casos y Controles , Metabolismo Energético , Polipéptido Inhibidor Gástrico/metabolismo , Péptido 2 Similar al Glucagón/metabolismo , Humanos , Secreción de Insulina/fisiología
20.
JAMA ; 323(23): 2397-2406, 2020 06 16.
Artículo en Inglés | MEDLINE | ID: mdl-32543682

RESUMEN

Importance: Continuous glucose monitoring (CGM) provides real-time assessment of glucose levels and may be beneficial in reducing hypoglycemia in older adults with type 1 diabetes. Objective: To determine whether CGM is effective in reducing hypoglycemia compared with standard blood glucose monitoring (BGM) in older adults with type 1 diabetes. Design, Setting, and Participants: Randomized clinical trial conducted at 22 endocrinology practices in the United States among 203 adults at least 60 years of age with type 1 diabetes. Interventions: Participants were randomly assigned in a 1:1 ratio to use CGM (n = 103) or standard BGM (n = 100). Main Outcomes and Measures: The primary outcome was CGM-measured percentage of time that sensor glucose values were less than 70 mg/dL during 6 months of follow-up. There were 31 prespecified secondary outcomes, including additional CGM metrics for hypoglycemia, hyperglycemia, and glucose control; hemoglobin A1c (HbA1c); and cognition and patient-reported outcomes, with adjustment for multiple comparisons to control for false-discovery rate. Results: Of the 203 participants (median age, 68 [interquartile range {IQR}, 65-71] years; median type 1 diabetes duration, 36 [IQR, 25-48] years; 52% female; 53% insulin pump use; mean HbA1c, 7.5% [SD, 0.9%]), 83% used CGM at least 6 days per week during month 6. Median time with glucose levels less than 70 mg/dL was 5.1% (73 minutes per day) at baseline and 2.7% (39 minutes per day) during follow-up in the CGM group vs 4.7% (68 minutes per day) and 4.9% (70 minutes per day), respectively, in the standard BGM group (adjusted treatment difference, -1.9% (-27 minutes per day); 95% CI, -2.8% to -1.1% [-40 to -16 minutes per day]; P <.001). Of the 31 prespecified secondary end points, there were statistically significant differences for all 9 CGM metrics, 6 of 7 HbA1c outcomes, and none of the 15 cognitive and patient-reported outcomes. Mean HbA1c decreased in the CGM group compared with the standard BGM group (adjusted group difference, -0.3%; 95% CI, -0.4% to -0.1%; P <.001). The most commonly reported adverse events using CGM and standard BGM, respectively, were severe hypoglycemia (1 and 10), fractures (5 and 1), falls (4 and 3), and emergency department visits (6 and 8). Conclusions and Relevance: Among adults aged 60 years or older with type 1 diabetes, continuous glucose monitoring compared with standard blood glucose monitoring resulted in a small but statistically significant improvement in hypoglycemia over 6 months. Further research is needed to understand the long-term clinical benefit. Trial Registration: ClinicalTrials.gov Identifier: NCT03240432.


Asunto(s)
Automonitorización de la Glucosa Sanguínea/métodos , Glucemia/análisis , Diabetes Mellitus Tipo 1/sangre , Hemoglobina Glucada/análisis , Hipoglucemia/prevención & control , Anciano , Automonitorización de la Glucosa Sanguínea/instrumentación , Diabetes Mellitus Tipo 1/tratamiento farmacológico , Diabetes Mellitus Tipo 1/psicología , Femenino , Humanos , Hiperglucemia/diagnóstico , Hipoglucemia/inducido químicamente , Hipoglucemia/diagnóstico , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/efectos adversos , Masculino , Persona de Mediana Edad , Monitoreo Ambulatorio/instrumentación , Medición de Resultados Informados por el Paciente
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