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1.
Anal Chem ; 96(19): 7401-7410, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38702865

RESUMO

Adsorption of a biofouling layer on the surface of biosensors decreases the electrochemical activity and hence shortens the service life of biosensors, particularly implantable and wearable biosensors. Real-time quantification of the loss of activity is important for in situ assessment of performance while presenting an opportunity to compensate for the loss of activity and recalibrate the sensor to extend the service life. Here, we introduce an electrochemical noise measurement technique as a tool for the quantification of the formation of a biofouling layer on the surface of gold. The technique uniquely affords thermodynamic and kinetic information without applying an external bias (potential and/or current), hence allowing the system to be appraised in its innate state. The technique relies on the analysis of non-faradaic current and potential fluctuations that are intrinsically generated by the interaction of charged species at the electrode surface, i.e., gold. An analytical model is extended to explain the significance of parameters drawn from statistical analysis of the noise signal. This concept is then examined in buffered media in the presence of albumin, a common protein in the blood and a known source of a fouling layer in biological systems. Results indicate that the statistical analysis of the noise signal can quantify the loss of electrochemical activity, which is also corroborated by impedance spectroscopy as a complementary technique.


Assuntos
Incrustação Biológica , Técnicas Eletroquímicas , Ouro , Ouro/química , Técnicas Eletroquímicas/métodos , Técnicas Biossensoriais , Propriedades de Superfície , Eletrodos , Adsorção
2.
Clin Radiol ; 79(1): e17-e25, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37923626

RESUMO

AIM: To investigate the role of the deep-learning (DL) method in the generation of dual-energy computed tomography (DECT) images from single-energy images for precise diagnosis of kidney stone type. MATERIALS AND METHODS: DECT of 23 patients was acquired, and the stone types were investigated based on the DECT software suggestions. The data were divided into two paired groups:120 kVp input and 80 kVp target and 120 kVp input and 135 kVp targets, p2p-UNet-GAN was exploited to generate the different energy images based on the common CT protocols. RESULTS: The images generated of the generative adversarial network (GAN) network were evaluated based on the SSIM, PSNR, and MSE metrics, and the values were estimated as 0.85-0.95, 28-32, and 0.85-0.89 respectively. The attenuation ratio of test patient images were estimated and compared with real patient reports. The network achieved high accuracy in stone region localisation and resulted in accurate stone type predictions. CONCLUSION: This study presents a useful method based on the DL technique to reduce patient radiation dose and facilitate the prediction of urinary stone types using single-energy CT imaging.


Assuntos
Cálculos Renais , Urolitíase , Humanos , Tomografia Computadorizada por Raios X/métodos , Cálculos Renais/diagnóstico por imagem , Cintilografia
3.
J Cardiothorac Vasc Anesth ; 38(1): 67-72, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38030427

RESUMO

OBJECTIVES: This study evaluated whether a novel standardized heparin dosing protocol used during atrial fibrillation catheter ablation resulted in a higher percentage of therapeutic activated clotting time (ACT) values compared to historic nonstandardized procedures. DESIGN: A retrospective cohort study SETTING: This study was conducted at Ochsner Medical Center, the largest tertiary-care teaching hospital in New Orleans, LA PARTICIPANTS: Patients undergoing catheter-based atrial fibrillation ablation INTERVENTIONS: The authors implemented a standardized heparin protocol, and enrolled 202 patients between November 2020 and March 2021. The historic controls consisted of 173 patients who underwent atrial fibrillation ablation between April 2020 and September 2020. Heparin administration in the control group was based on physician preference and was nonstandardized. MEASUREMENTS AND MAIN RESULTS: The primary endpoint was the percentage of intraprocedural ACTs in therapeutic range (≥300 to <450 s). Secondary endpoints included first measured ACT at ≥300 s and percent of measured ACTs in the supratherapeutic range (>450 s). Comparisons were performed using chi-squared tests or Fisher exact tests. Patients in the intervention group had a higher mean percentage of ACTs in the therapeutic range compared to the control group (84.9% vs. 75.8%, p<0.001). More patients in the intervention group reached therapeutic ACT on the first measurement compared to the control group (70.3% vs. 31.2%, p<0.001). CONCLUSION: During catheter-based cardiac ablation procedures, a novel standardized unfractionated heparin dosing protocol resulted in a higher percentage of ACTs in the target range, and a higher proportion of initial ACTs in the therapeutic range compared with baseline nonstandardized heparin dosing.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Humanos , Heparina , Anticoagulantes , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Ablação por Cateter/métodos
4.
Ann Pharmacother ; 56(2): 139-145, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34049437

RESUMO

BACKGROUND: It is well established that females and persons of racial and ethnic minorities are frequently underrepresented in clinical trials. These disparities are potentially important aspects of evidence-based formulary management and drug utilization review (DUR) processes. OBJECTIVE: The purpose of this study was to review the demographic composition of pivotal trials and post-approval study requirements for recent FDA-approved drugs, analyzing the representation of minority groups and its generalizability to the US population or corresponding disease state. METHODS: Drugs approved between July 2019 and June 2020 were identified and demographic data including race, ethnicity, and sex was extracted from their pivotal trials. Demographic data was compared to US demographics and/or the disease state demographics for the respective approved drug. RESULTS: There were a total of 85 drugs and 142 pivotal trials included in the study. Compared to the estimated US population, the minority groups with a statistically significant underrepresentation across all pivotal trials included Black or African Americans and American Indian or Alaska Natives. The Hispanic/Latinx population had a statistically significant underrepresentation in 55.4% of trials. Females had a statistically significant underrepresentation in 21.2% of trials when compared to the disease state demographics of the respective approved drug. CONCLUSION AND RELEVANCE: Persons of minorities are underrepresented in the generation of evidence of safety and efficacy for many new drugs. Formulary management and DUR offer an integrated strategic opportunity for the clinical community to formally and carefully consider the data on sex, race, and ethnicity to address disparities in health care.


Assuntos
Etnicidade , Preparações Farmacêuticas , Minorias Étnicas e Raciais , Feminino , Hispânico ou Latino , Humanos , Grupos Minoritários , Estados Unidos
5.
J Nutr ; 151(10): 2932-2941, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34255069

RESUMO

BACKGROUND: l-Tryptophan reduces energy intake in healthy men. The underlying mechanisms, including appetite, plasma cholecystokinin (CCK), tryptophan (Trp), and the ratio of Trp to large neutral amino acids (Trp:LNAAs ratio), and whether responses differ in lean and obese individuals, are uncertain. OBJECTIVES: We evaluated the effects of intragastric Trp on energy intake (primary outcome) and their potential mechanisms, pre- and postmeal, in lean men and those with obesity. METHODS: Twelve lean men [mean ± SD age: 30 ± 3 y; BMI (in kg/m2): 23 ± 1] and 13 men with obesity (mean ± SD age: 31 ± 3 y; BMI: 33 ± 1) received, on 3 separate occasions, in double-blind, randomized order, 3 g ("Trp-3") or 1.5 g ("Trp-1.5") Trp, or control ("C"), intragastrically, 30 min before a buffet-meal. Energy intake from the buffet-meal, hunger, fullness, and plasma CCK and amino acid concentrations were measured in response to Trp alone and for 2 h postmeal. Data were analyzed using maximum likelihood mixed-effects models, with treatment, group, and treatment-by-group interaction as fixed effects. RESULTS: Trp alone increased plasma CCK, Trp, and the Trp:LNAAs ratio (all P < 0.001), with no difference between groups. Trp suppressed energy intake (P < 0.001), with no difference between groups (lean, C: 1085 ± 102 kcal, Trp-1.5: 1009 ± 92 kcal, Trp-3: 868 ± 104 kcal; obese, C: 1249 ± 98 kcal, Trp-1.5: 1217 ± 90 kcal, Trp-3: 1012 ± 100 kcal). Postmeal, fullness was greater after Trp-3 than after C and Trp-1.5 (all P < 0.05), and in men with obesity than in lean men (P < 0.05). Plasma Trp and the Trp:LNAAs ratio were greater after Trp-3 and Trp-1.5 than after C (all P < 0.001), and tended to be less in men with obesity than in the lean (P = 0.07) (Trp:LNAAs ratio: lean, C: 1.5 ± 0.2, Trp-1.5: 6.9 ± 0.7, Trp-3: 10.7 ± 1.4; obese, C: 1.4 ± 0.1, Trp-1.5: 4.6 ± 0.7, Trp-3: 7.8 ± 1.3). There were inverse correlations of energy intake with plasma Trp and the Trp:LNAAs ratio in both groups (lean, both r = -0.50, P < 0.01; obese, both r = -0.40, P < 0.05). CONCLUSIONS: Intragastric Trp has potent energy intake-suppressant effects, in both lean men and those with obesity, apparently related to the Trp:LNAAs ratio.


Assuntos
Apetite , Triptofano , Adulto , Colecistocinina , Método Duplo-Cego , Ingestão de Energia , Humanos , Masculino , Obesidade
6.
Biomacromolecules ; 22(1): 134-145, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-32567847

RESUMO

Enzymes are essential biocatalysts and very attractive as therapeutics. However, their functionality is strictly related to their stability, which is significantly affected by the environmental changes occurring during their usage or long-term storage. Therefore, maintaining the activity of enzymes is essential when they are exposed to high temperature during usage or when they are stored for extended periods of time. Here, we stabilize and protect enzymes by coencapsulating them with trehalose into polymersomes. The anhydrobiotic disaccharide preserved up to about 81% of the enzyme's original activity when laccase/trehalose-loaded nanoreactors were kept desiccated for 2 months at room temperature and 75% of its activity when heated at 50 °C for 3 weeks. Moreover, the applicability of laccase/trehalose-loaded nanoreactors as catalysts for bleaching of the textile dyes orange G, toluidine blue O, and indigo was proven. Our results demonstrate the advantages of coencapsulating trehalose within polymersomes to stabilize enzymes in dehydrated state for extended periods of time, preserving their activity even when heated to elevated temperature.


Assuntos
Lacase , Trealose , Preservação Biológica
7.
Am J Physiol Regul Integr Comp Physiol ; 318(4): R790-R798, 2020 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-32160019

RESUMO

The fatty acid, lauric acid (C12), and the amino acid, leucine (Leu) stimulate gut hormones, including CCK, associated with suppression of energy intake. In our recent study, intraduodenal infusion of a combination of C12 and l-tryptophan, at loads that individually did not affect energy intake, reduced energy intake substantially, associated with much greater stimulation of CCK. We have now investigated whether combined administration of C12 and Leu would enhance the intake-suppressant effects of each nutrient, when given at loads that each suppress energy intake individually. Sixteen healthy, lean males (age: 23 ± 2 yr) received, in randomized, double-blind fashion, 90-min intraduodenal infusions of control (saline), C12 (0.4 kcal/min), Leu (0.45 kcal/min), or C12+Leu (0.85 kcal/min). Antropyloroduodenal pressures were measured continuously and plasma CCK at 15-min intervals, and energy intake from a standardized buffet-meal, consumed immediately postinfusion, was quantified. All nutrient infusions stimulated plasma CCK compared with control (P < 0.05). Moreover, C12 and C12+Leu stimulated CCK compared with Leu (P < 0.05) (mean concentration, pmol/L; control: 2.3 ± 0.3, C12: 3.8 ± 0.3, Leu: 2.7 ± 0.3, and C12+Leu: 4.0 ± 0.4). C12+Leu, but not C12 or Leu, stimulated pyloric pressures (P < 0.05). C12+Leu and C12 reduced energy intake (P < 0.05), and there was a trend for Leu to reduce (P = 0.06) energy intake compared with control, with no differences between the three nutrient treatments (kcal; control: 1398 ± 84, C12: 1226 ± 80, Leu: 1260 ± 92, and C12+Leu: 1208 ± 83). In conclusion, combination of C12 and Leu, at the loads given, did not reduce energy intake beyond their individual effects, possibly because maximal effects had been evoked.


Assuntos
Colecistocinina/sangue , Ingestão de Energia , Motilidade Gastrointestinal/efeitos dos fármacos , Ácidos Láuricos/farmacologia , Leucina/farmacologia , Adolescente , Adulto , Apetite/efeitos dos fármacos , Método Duplo-Cego , Ingestão de Alimentos/efeitos dos fármacos , Humanos , Ácidos Láuricos/administração & dosagem , Leucina/administração & dosagem , Masculino , Adulto Jovem
8.
Bull Exp Biol Med ; 165(1): 115-120, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29797118

RESUMO

We studied physiological parameters of rhesus monkeys after administration of anthracycline antibiotic doxorubicin. Intravenous administration of the drug caused intoxication manifested in in an abrupt body weight loss, baldness, vomiting, and exicosis. Intoxication in monkeys determined by the damaging effects of doxorubicin on organs and tissues is also characterized by significant changes in the blood: leukopenia, thrombocytopenia, neutropenia, monocytopenia, lymphocytosis, and a sharp drop of CD20+ B cell content. The total protein and albumin content in the blood significantly decreased. A sharp increase in C-reactive protein was also accompanied by an increase in activity of proinflammatory cytokine IL-6. Transplantation of mesenchymal stem cells in some cases can significantly alleviate doxorubicin-induced damage to organs and maintain normal clinical status of monkeys after two injections of the drug. Late transplantation of stem cells does not have a protective effect and does not protect the animals from the damaging effects of doxorubicin. We found that the protective effect of mesenchymal stem cells depends on the dose of the drug, total number of cells, and the time of their transplantation. It should be noted that human and monkey mesenchymal stem cells produce similar regenerative effects, at least in the doxorubicin toxicity model.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Doxorrubicina/toxicidade , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Alopecia/induzido quimicamente , Animais , Peso Corporal/efeitos dos fármacos , Proteína C-Reativa/metabolismo , Humanos , Interleucina-6/metabolismo , Macaca mulatta , Masculino
9.
Bull Exp Biol Med ; 165(1): 101-104, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29797125

RESUMO

Three injections of doxorubicin to rhesus macaques cause severe intoxication, characterized by anemia, cachexia, and degeneration of the viscera. The life span of monkeys injected with the drug and receiving after 24 h mesenchymal stem cell transplantation varied from 96 to 120 days in comparison with 50-74 days in animals receiving stem cells before doxorubicin. Controls received doxorubicin and saline; the lifespan of one monkey was 24 days, of the other - 1 year and 8 months. The increase in activity of proinflammatory cytokine IL-6 was paralleled by an increase in the level of C-reactive protein.


Assuntos
Doxorrubicina/efeitos adversos , Células-Tronco Mesenquimais/fisiologia , Animais , Linfócitos B/efeitos dos fármacos , Linfócitos B/metabolismo , Citocinas/metabolismo , Interleucina-6/metabolismo , Macaca mulatta , Transplante de Células-Tronco Mesenquimais , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo
10.
J Nutr ; 147(7): 1275-1281, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28592515

RESUMO

Background: Lysine is reported to lower the glycemic response to oral glucose in humans and, albeit at high loads, to slow gastric emptying of glucose and decrease food intake in rats.Objective: We investigated the effects of intragastrically administered lysine on early (15 min) and later (60 min) blood glucose and insulin responses to and gastric emptying of a mixed-nutrient drink, and effects on subsequent energy intake.Methods: Twelve healthy volunteers (7 men and 5 women; mean ± SEM age: 24 ± 2 y) received intragastric infusions (200 mL) containing 5 or 10 g l-lysine or a control solution within 2 min on 3 different occasions in randomized order. Fifteen minutes later, participants consumed a mixed-nutrient drink (300 mL, 400 kcal, and 56 g carbohydrates) within 1 min. For the next hour (t = 0-60 min), we collected blood samples every 15 min (to measure blood glucose, plasma insulin, and plasma glucagon) and breath samples every 5 min (to measure gastric emptying via a 13C-acetate breath test). We then quantified subjects' energy intake from a buffet-style meal (t = 60-90 min).Results: There were no differences between the 2 lysine treatments; hence, data were pooled for further analysis. Lysine did not affect blood glucose at 15 min or the blood glucose area under the curve from 0 to 60 min (AUC0-60min) but it decreased blood glucose at 60 min compared with the control solution (-9.1% ± 3.1%, P < 0.01). Similarly, the early insulin response and insulin AUC0-60min were not affected by lysine, but plasma insulin at 60 min was 20.9% ± 5.6% lower than after the control (P < 0.05). Plasma glucagon at both 15 min (20.7% ± 4.7%, P < 0.001) and 60 min (14.1% ± 5.4%, P < 0.05) and the glucagon AUC0-60min (P < 0.01) were greater after lysine than after the control. Lysine did not slow gastric emptying, and there was no effect on energy intake.Conclusion: In healthy adults, lysine slightly reduced the glycemic response to an oral mixed-macronutrient drink, an effect that was apparently independent of insulin or slowing of gastric emptying. This trial was registered at www.anzctr.orgau as 12614000837628.


Assuntos
Bebidas/análise , Glicemia/metabolismo , Carboidratos da Dieta/farmacologia , Esvaziamento Gástrico/efeitos dos fármacos , Insulina/sangue , Lisina/farmacologia , Adulto , Testes Respiratórios , Dióxido de Carbono , Carboidratos da Dieta/análise , Relação Dose-Resposta a Droga , Método Duplo-Cego , Ingestão de Alimentos , Feminino , Humanos , Lisina/administração & dosagem , Masculino , Adulto Jovem
11.
Am J Physiol Regul Integr Comp Physiol ; 308(4): R300-4, 2015 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-25568079

RESUMO

Intraduodenal infusion of lipid or protein potently reduces subsequent energy intake. There is evidence that the underlying mechanisms differ significantly between the two nutrients. While intraduodenal lipid stimulates glucagon-like peptide-1 and CCK much more than protein, the release of insulin and glucagon is substantially greater in response to protein. Ghrelin and PYY are both involved in short-term regulation, while leptin is a long-term regulator, of energy balance; the acute effects of nutrients on leptin release are unclear. We investigated the comparative effects of intraduodenal lipid and protein on plasma ghrelin, PYY, and leptin concentrations. Thirteen lean, young men received 90-min intraduodenal infusions of protein (whey hydrolysate) or lipid (long-chain triglyceride emulsion) at a rate of 3 kcal/min, or saline control, on three separate days. Blood samples were collected at baseline and regularly during infusions. Both lipid and protein potently suppressed plasma ghrelin compared with control (both P < 0.001), with no difference between them. While both lipid and protein stimulated plasma PYY (P < 0.001), the effect of lipid was substantially greater than that of protein (P < 0.001). Neither intraduodenal lipid nor protein affected plasma leptin. In conclusion, intraduodenal lipid and protein have discrepant effects on the release of PYY, but not ghrelin. When considered with our previous findings, it appears that, with the exception of ghrelin, the energy intake-suppressant effects of lipid and protein are mediated by different mechanisms.


Assuntos
Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Duodeno/efeitos dos fármacos , Grelina/sangue , Leptina/sangue , Proteínas do Leite/administração & dosagem , Peptídeo YY/sangue , Hidrolisados de Proteína/administração & dosagem , Triglicerídeos/administração & dosagem , Adolescente , Adulto , Estudos Cross-Over , Método Duplo-Cego , Duodeno/metabolismo , Ingestão de Alimentos , Metabolismo Energético , Voluntários Saudáveis , Humanos , Masculino , Período Pós-Prandial , Fatores de Tempo , Proteínas do Soro do Leite , Adulto Jovem
12.
Biomacromolecules ; 15(4): 1469-75, 2014 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-24650106

RESUMO

Laccases (Lac) are oxidizing enzymes with a broad range of applications, for example, in soil remediation, as bleaching agent in the textile industry, and for cosmetics. Protecting the enzyme against degradation and inhibition is of great importance for many of these applications. Polymer vesicles (polymersomes) from poly(N-vinylpyrrolidone)-block-poly(dimethylsiloxane)-block-poly(N-vinylpyrrolidone) (PNVP-b-PDMS-b-PNVP) triblock copolymers were prepared and investigated as intrinsically semipermeable nanoreactors for Lac. The block copolymers allow oxygen to enter and reactive oxygen species (ROS) to leave the polymersomes. EPR spectroscopy proved that Lac can generate ROS. They could diffuse out of the polymersome and oxidize an aromatic substrate outside the vesicles. Michaelis-Menten constants Km between 60 and 143 µM and turn over numbers kcat of 0.11 to 0.18 s(-1) were determined for Lac in the nanoreactors. The molecular weight and the PDMS-to-PNVP ratio of the block copolymers influenced these apparent Michaelis-Menten parameters. Encapsulation of Lac in the polymersomes significantly protected the enzyme against enzymatic degradation and against small inhibitors: proteinase K caused 90% less degradation and the inhibitor sodium azide did not affect the enzyme's activity. Therefore, these polymer nanoreactors are an effective means to stabilize laccase.


Assuntos
Lacase/química , Lacase/metabolismo , Nanotecnologia/métodos , Povidona/análogos & derivados , Siloxanas/química , Espectroscopia de Ressonância de Spin Eletrônica , Endopeptidase K/metabolismo , Estabilidade Enzimática , Interações Hidrofóbicas e Hidrofílicas , Lacase/antagonistas & inibidores , Peso Molecular , Oxigênio/metabolismo , Povidona/síntese química , Povidona/química , Espécies Reativas de Oxigênio/metabolismo , Siloxanas/síntese química , Azida Sódica/metabolismo , Azida Sódica/farmacologia
13.
Int J Immunopathol Pharmacol ; 27(3): 461-5, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25280040

RESUMO

Extranodal non-Hodgkin lymphomas limited to the larynx are rare, accounting for less than 1% of all laryngeal neoplasms. The most common site of development of primary laryngeal lymphomas is the supraglottic region. In most cases, the presenting symptoms are hoarseness, dysphagia, dyspnea, and cervical lymphadenopathy. They consist mainly of non-Hodgkin lymphoma, especially of diffuse large B-cell lymphoma and mucosa-associated lymphoid tissue. We report a case of a primary extranodal marginal zone of mucosa-associated lymphoid tissue (Malt Lymphoma) of the larynx in a 73-year-old non-smoker woman, presented as chronic cough, unresponsive to oral corticosteroid. We present a detailed report of her clinical and paraclinical data as well as treatment options. In patients with chronic cough, uncommon causes should be considered when the cough persists after evaluation for common causes. If a cough persists after consideration of the most common causes, CT scan and a bronchoscopic evaluation are fundamental for the diagnosis of tumors of the upper and lower respiratory tract.


Assuntos
Tosse/etiologia , Neoplasias Laríngeas/diagnóstico , Linfoma de Zona Marginal Tipo Células B/diagnóstico , Idoso , Feminino , Humanos , Neoplasias Laríngeas/patologia , Linfoma de Zona Marginal Tipo Células B/patologia
14.
Bull Exp Biol Med ; 157(1): 143-5, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24909728

RESUMO

The use of triple systemic transplantation of cardiomyoblasts raised from the culture of allogenic bone marrow mesenchymal stem cells of a healthy donor according to the new medical technology licensed by Federal Service on Surveillance in Healthcare in the therapy of a patient with late radiation cardiomyopathy and radiation exudative pericarditis developed 45 years after radiation therapy for Hodgkin lymphoma. High efficiency of systemic transplantation of mesenchymal stem cells partially differentiated towards cardiomyocytes was demonstrated. The therapeutic effect persists for more than 2 years. Possible mechanisms of the therapeutic effect of this type of stem cells and the prospects of using cell therapy in the treatment of late radiation injuries of vital organs and tissues are discussed.


Assuntos
Cardiomiopatias/terapia , Transplante de Células-Tronco Mesenquimais , Mioblastos Cardíacos/transplante , Pericardite/terapia , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/etiologia , Cardiomiopatias/patologia , Diferenciação Celular , Raios gama/efeitos adversos , Doença de Hodgkin/complicações , Doença de Hodgkin/diagnóstico por imagem , Doença de Hodgkin/patologia , Doença de Hodgkin/radioterapia , Humanos , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Pessoa de Meia-Idade , Mioblastos Cardíacos/citologia , Mioblastos Cardíacos/fisiologia , Pericardite/diagnóstico por imagem , Pericardite/etiologia , Pericardite/patologia , Transplante Homólogo , Resultado do Tratamento , Ultrassonografia
15.
ACS Omega ; 9(16): 17966-17976, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38680325

RESUMO

The addition of nanomaterials to improve product properties has become a matter of course for many commodities: e.g., detergents, cosmetics, and food products. While this practice improves product characteristics, the increasing exposure and potential impact of nanomaterials (<100 nm) raise concerns regarding both the human body and the environment. Special attention should be taken for vulnerable individuals such as those who are ill, elder, or newborns. But detecting and quantifying nanoparticles in complex food matrices like early life nutrition (ELN) poses a significant challenge due to the presence of additional particles, emulsion-droplets, or micelles. There is a pressing demand for standardized protocols for nanoparticle quantification and the specification of "nanoparticle-free" formulations. To address this, silica nanoparticles (SiNPs), commonly used as anticaking agents (AA) in processed food, were employed as a model system to establish characterization methods with different levels of accuracy and sensitivity versus speed, sample handling, and automatization. Different acid treatments were applied for sample digestion, followed by size exclusion chromatography. Morphology, size, and number of NPs were measured by transmission electron microscopy, and the amount of Si was determined by microwave plasma atomic emission spectrometry. This successfully enabled distinguishing SiNP content in ELN food formulations with 2-4% AA from AA-free formulations and sorting SiNPs with diameters of 20, 50, and 80 nm. Moreover, the study revealed the significant influence of the ELN matrix on sample preparation, separation, and characterization steps, necessitating method adaptations compared to the reference (SiNP in water). In the future, we expect these methods to be implemented in standard quality control of formulation processes, which demand high-throughput analysis and automated evaluation.

16.
J Bone Miner Res ; 38(12): 1731-1741, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37597237

RESUMO

The American Society of Bone and Mineral Research (ASBMR) Professional Practice Committee charged an ASBMR Task Force on Clinical Algorithms for Fracture Risk to review the evidence on whether current approaches for differentiating fracture risk based on race and ethnicity are necessary and valid. To help address these charges, we performed a systematic literature review investigating performance of calculators for predicting incident fractures within and across race and ethnicity groups in middle-aged and older US adults. We included English-language, controlled or prospective cohort studies that enrolled US adults aged >40 years and reported tool performance predicting incident fractures within individual race and ethnicity groups for up to 10 years. From 4838 identified references, six reports met eligibility criteria, all in women. Just three, all from one study, included results in non-white individuals. In these three reports, non-white women experienced relatively few major osteoporotic fractures (MOFs), especially hip fractures, and risk thresholds for predicting fractures in non-white women were derived from risks in the overall, predominantly white study population. One report suggested the Fracture Risk Assessment Tool (FRAX) without bone mineral density (BMD) overestimated hip fracture similarly across race and ethnicity groups (black, Hispanic, American Indian, Asian, white) but overestimated MOF more in non-white than White women. However, these three reports were inconclusive regarding whether discrimination of FRAX or the Garvan calculator without BMD or of FRAX with BMD for MOF or hip fracture differed between white versus black women. This uncertainty was at least partly due to imprecise hip fracture estimates in black women. No reports examined whether ratios of observed to predicted hip fracture risks within each race or ethnicity group varied across levels of predicted hip fracture risk. © 2023 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR). This article has been contributed to by U.S. Government employees and their work is in the public domain in the USA.


Assuntos
Fraturas do Quadril , Fraturas por Osteoporose , Adulto , Pessoa de Meia-Idade , Humanos , Feminino , Idoso , Etnicidade , Estudos Prospectivos , Medição de Risco/métodos , Fraturas por Osteoporose/epidemiologia , Fraturas do Quadril/epidemiologia , Densidade Óssea , Algoritmos , Minerais , Fatores de Risco
17.
PeerJ ; 11: e15766, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37637176

RESUMO

The Indonesian island of Sulawesi has a unique geology and geography, which have produced an astoundingly diverse and endemic flora and fauna and a fascinating biogeographic history. Much biodiversity research has focused on the regional endemism in the island's Central Core and on its four peninsulas, but the biodiversity of the island's many upland regions is still poorly understood for most taxa, including amphibians and reptiles. Here, we report the first of several planned full-mountain checklists from a series of herpetological surveys of Sulawesi's mountains conducted by our team. In more than 3 weeks of work on Gunung Galang, a 2,254 m peak west of the city of Tolitoli, Sulawesi Tengah Province, on Sulawesi's Northern Peninsula, we recovered nearly fifty species of reptiles and amphibians, more than a dozen of which are either new to science or known but undescribed. The incompleteness of our sampling suggests that many more species remain to be discovered on and around this mountain.


Assuntos
Biodiversidade , Lista de Checagem , Indonésia , Geografia , Geologia
18.
J Am Chem Soc ; 134(1): 247-55, 2012 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-22126191

RESUMO

Understanding and controlling cell adhesion on engineered scaffolds is important in biomaterials and tissue engineering. In this report we used an electron-beam (e-beam) lithography technique to fabricate patterns of a cell adhesive integrin ligand combined with a growth factor. Specifically, micron-sized poly(ethylene glycol) (PEG) hydrogels with aminooxy- and styrene sulfonate-functional groups were fabricated. Cell adhesion moieties were introduced using a ketone-functionalized arginine-glycine-aspartic acid (RGD) peptide to modify the O-hydroxylamines by oxime bond formation. Basic fibroblast growth factor (bFGF) was immobilized by electrostatic interaction with the sulfonate groups. Human umbilical vein endothelial cells (HUVECs) formed focal adhesion complexes on RGD- and RGD and bFGF-immobilized patterns as shown by immunostaining of vinculin and actin. In the presence of both bFGF and RGD, cell areas were larger. The data demonstrate confinement of cellular focal adhesions to chemically and physically well-controlled microenvironments created by a combination of e-beam lithography and "click" chemistry techniques. The results also suggest positive implications for addition of growth factors into adhesive patterns for cell-material interactions.


Assuntos
Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Elétrons , Fatores de Crescimento de Fibroblastos/metabolismo , Integrinas/metabolismo , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Materiais Biocompatíveis/metabolismo , Adesão Celular/efeitos dos fármacos , Matriz Extracelular/efeitos dos fármacos , Matriz Extracelular/metabolismo , Adesões Focais/efeitos dos fármacos , Adesões Focais/metabolismo , Células Endoteliais da Veia Umbilical Humana , Humanos , Ligantes , Metacrilatos/química , Polietilenoglicóis/química , Silício/química
19.
J Appl Clin Med Phys ; 13(2): 3687, 2012 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-22402384

RESUMO

Accuracy of treatment planning systems may significantly influence the efficacy of brachytherapy. The purpose of this work is a detailed, varied and independent evaluation of an in-house brachytherapy treatment planning software called STPS. Operational accuracy of STPS was investigated. Geometric tests were performed to validate entry and reconstruction of positional information from scanned orthogonal films. MCNP4C Monte Carlo code and TLDs were used for simulation and experimental measurement, respectively. STPS data were also compared with those from a commercial planning system (Nucletron PLATO). Discrepancy values between MCNP and STPS data and also those of PLATO and STPS at Manchester system dose prescription points (AL and AR) of tandem and ovoid configurations were 2.5% ± 0.5% and 5.4% ± 0.4%, respectively. Similar results were achieved for other investigated configurations. Observed discrepancies between MCNP and STPS at the dose prescription point and at 1 cm from the tip of the vaginal applicator were 4.5% and 25.6% respectively, while the discrepancy between the STPS and PLATO data at those points was 2.3%. The software showed submillimeter accuracy in its geometrical reconstructions. In terms of calculation accuracy, similar to PLATO, as attenuation of the sources and applicator body is not considered, dose was overestimated at the tip of the applicator, but based on the available criteria, dose accuracy at most points were acceptable. Our results confirm STPS's geometrical and operational reliability, and show that its dose computation accuracy is comparable to an established commercial TPS using the same algorithm.


Assuntos
Algoritmos , Braquiterapia/instrumentação , Método de Monte Carlo , Planejamento da Radioterapia Assistida por Computador , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/radioterapia , Simulação por Computador , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imagens de Fantasmas , Radiografia , Dosagem Radioterapêutica , Software , Neoplasias do Colo do Útero/patologia , Água/química
20.
Bull Exp Biol Med ; 154(1): 133-5, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23330109

RESUMO

We describe the methods of isolation and culturing of mesenchymal stem cells from 3 monkey species Macaca mulatta, Papio hamadryas, and Macaca fascicularis. Flow cytofluorometry showed that the cells do not express CD34, CD45, and HLA-DR, but most of them (78-98%) express CD90 marker. The cardioprotective effects of cultured mesenchymal stem cells in cardiomyopathy induced by administration of antitumor anthracycline drugs (doxorubicin).


Assuntos
Cardiomiopatias/prevenção & controle , Cardiomiopatias/terapia , Macaca , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Papio hamadryas , Animais , Antígenos CD34/metabolismo , Azacitidina , Cardiomiopatias/induzido quimicamente , Técnicas de Cultura de Células , Diferenciação Celular , Separação Celular , Células Cultivadas , Doxorrubicina , Antígenos HLA-DR/metabolismo , Antígenos Comuns de Leucócito/metabolismo , Macaca fascicularis , Macaca mulatta , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Antígenos Thy-1/metabolismo
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