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1.
Chem Mater ; 36(11): 5552-5562, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38883433

RESUMO

Conjugated polymers are a versatile class of electronic materials featured in a variety of next-generation electronic devices. The utility of such polymers is contingent in large part on their electrical conductivity, which depends both on the density of charge carriers (polarons) and on the carrier mobility. Carrier mobility, in turn, is largely controlled by the separation between the polarons and dopant counterions, as counterions can produce Coulombic traps. In previous work, we showed that large dopants based on dodecaborane (DDB) clusters were able to reduce Coulombic binding and thus increase carrier mobility in regioregular (RR) poly(3-hexylthiophene-2,5-diyl) (P3HT). Here, we use a DDB-based dopant to study the effects of polaron-counterion separation in chemically doped regiorandom (RRa) P3HT, which is highly amorphous. X-ray scattering shows that the DDB dopants, despite their large size, can partially order the RRa P3HT during doping and produce a doped polymer crystal structure similar to that of DDB-doped RR P3HT; Alternating Field (AC) Hall measurements also confirm a similar hole mobility. We also show that use of the large DDB dopants successfully reduces Coulombic binding of polarons and counterions in amorphous polymer regions, resulting in a 77% doping efficiency in RRa P3HT films. The DDB dopants are able to produce RRa P3HT films with a 4.92 S/cm conductivity, a value that is ∼200× higher than that achieved with 3,5,6-tetrafluoro-7,7,8,8-tetracyanoquinodimethane (F4TCNQ), the traditional dopant molecule. These results show that tailoring dopants to produce mobile carriers in both the amorphous and semicrystalline regions of conjugated polymers is an effective strategy for increasing achievable polymer conductivities, particularly in low-cost polymers with random regiochemistry. The results also emphasize the importance of dopant size and shape for producing Coulombically unbound, mobile polarons capable of electrical conduction in less-ordered materials.

2.
Molecules ; 26(11)2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34071495

RESUMO

Increasing applications and markets for essential oils could bring new opportunities for cost-effective and sustainable management of unused forestry biomass; however, better knowledge of the production and application of such essential oils is necessary. The objective of this work is to contribute to greater knowledge of the essential oil production on a pilot scale from foliage biomass of wild shrubs and tree residues produced in some forestry enhancement operations and to study their antioxidant capacity (ORAC-oxygen radical absorbance capacity). Fresh biomass (twigs) of seven species (E. globulus, E. nitens, P. pinaster, P. sylvestris, R. officinalis, C. ladanifer, and J. communis) was manually collected in Spain in two different periods and was ground at 30 mm and distilled in a 30 L stainless steel still with saturated steam. The essential oil components were identified by GC-MS and quantified by GC-FID, and their antioxidant activity was determined with the ORAC method. Promising results on essential oil yield were obtained with E. globulus, E. nitens, R. officinalis, and J. communis. All essential oils studied exhibited antioxidant capacity by the ORAC assay, particularly that from C. ladanifer. Moreover, oxygenated sesquiterpenes contents, one of the minor components of oils, were significantly correlated with ORAC values.


Assuntos
Antioxidantes/química , Óleos Voláteis/química , Folhas de Planta/metabolismo , Biomassa , Cromatografia Gasosa , Cistus , Eucalyptus/química , Florestas , Cromatografia Gasosa-Espectrometria de Massas , Geografia , Monoterpenos/análise , Óleos de Plantas/química , Sesquiterpenos/análise , Espanha , Árvores
3.
Molecules ; 26(8)2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33921855

RESUMO

Cistus ladanifer is a Mediterranean native plant from which valuable products, such as essential oil, are obtained. Manual harvesting of the plants in wild shrublands is usual during short periods of time. Their mechanised harvesting could increase the volume of harvested plants and prevent fires, further storage of the plants collected being necessary. The objective of this work is to study the influence of the storage period of mechanically harvested bales on the essential oil yield and qualitative composition. The harvesting trials were carried out with an adapted commercial harvester baler and the storage of the bales was performed indoors during 1-7 days, 15-30 days and 100-120 days. Afterwards, the bales were crushed (30 mm) and distilled in a 30 litre stainless steel still with saturated steam (0.5 bar). The essential oil components were identified by GC-MS and quantified by GC-FID. The storage of mechanically harvested Cistus ladanifer does not decrease the oil yield of steam distillation on a pilot scale. However, it leads to differences in the quantitative composition of the essential oils, decreasing the total monoterpene compounds content and increasing that of oxygenated sesquiterpenes, especially when the biomass is stored for 100-120 days, without affecting its qualitative composition.


Assuntos
Cistus/química , Óleos Voláteis/análise , Cromatografia Gasosa , Cromatografia Gasosa-Espectrometria de Massas , Monoterpenos/análise
4.
ACS Omega ; 4(21): 19172-19176, 2019 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-31763540

RESUMO

The effects of cellulose nanocrystals (CNCs) (12, 24, and 36% w/w) on the microstructure and mechanical and thermal properties of canola protein isolate films were evaluated. The incorporation of cellulose nanocrystals led to homogeneous films, and new Fourier transform infrared peaks appeared at 1055 cm-1, indicating the presence and the interaction of CNCs with proteins and glycerol. The addition of CNCs also improved the thermal stability of the films, since higher temperatures were required for their thermal decomposition. In addition, CNC addition resulted in an increase in tensile strength and a decrease in elongation at break values due to strong interactions between the OH groups in proteins, glycerol, and CNCs.

5.
Front Aging Neurosci ; 11: 261, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31619985

RESUMO

Stroke remains a leading cause of death and disability in the United States. No current treatments exist to promote cognitive recovery in survivors of stroke. A previous study from our laboratory determined that an acute bout of forced treadmill exercise was able to promote cognitive recovery in 3 month old male rats after middle cerebral artery occlusion (MCAo). In this study, we tested the hypothesis that 6 days of intense acute bout of forced treadmill exercise (physical exercise - PE) promotes cognitive recovery in 11-14 month old male rats. We determined that PE was able to ameliorate cognitive deficits as determined by contextual fear conditioning. Additionally, we also tested the hypothesis that PE promotes cognitive recovery in 11-13 month old reproductive senescent female rats. In contrast to males, the same intensity of exercise that decrease cognitive deficits in males was not able to promote cognitive recovery in female rats. Additionally, we determined that exercise did not lessen infarct volume in both male and female rats. There are many factors that contribute to higher stroke mortality and morbidities in women and thus, future studies will investigate the effects of PE in aged female rats to identify sex differences.

6.
Ann Hepatol ; 18(4): 543-552, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31126880

RESUMO

Acute liver failure (ALF) is a severe condition secondary to a myriad of causes associated with poor outcomes. The prompt diagnosis and identification of the aetiology allow the administration of specific treatments plus supportive strategies and to define the overall prognosis, the probability of developing complications and the need for liver transplantation. Pivotal issues are adequate monitoring and the institution of prophylactic strategies to reduce the risk of complications, such as progressive liver failure, cerebral oedema, renal failure, coagulopathies or infections. In this article, we review the main aspects of ALF, including the definition, diagnosis and complications. Also, we describe the standard-of-care strategies and recent advances in the treatment of ALF. Finally, we include our experience of care patients with ALF.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/terapia , Falência Hepática Aguda/terapia , Acetaminofen/intoxicação , Injúria Renal Aguda/etiologia , Injúria Renal Aguda/terapia , Amanita , Analgésicos não Narcóticos/intoxicação , Biópsia , Transtornos da Coagulação Sanguínea/sangue , Transtornos da Coagulação Sanguínea/etiologia , Transtornos da Coagulação Sanguínea/terapia , Edema Encefálico/prevenção & controle , Edema Encefálico/terapia , Circulação Extracorpórea , Feminino , Hemorragia/etiologia , Hemorragia/terapia , Hepatite B/terapia , Hepatite Autoimune/terapia , Humanos , Hipertensão Intracraniana/etiologia , Hipertensão Intracraniana/terapia , Fígado/patologia , Falência Hepática Aguda/complicações , Falência Hepática Aguda/patologia , Transplante de Fígado , Intoxicação Alimentar por Cogumelos/terapia , Troca Plasmática , Gravidez , Complicações na Gravidez/terapia , Terapia de Substituição Renal , Respiração Artificial , Medição de Risco , Sepse/etiologia , Sepse/terapia , Desintoxicação por Sorção , Tromboelastografia
7.
Rev Med Chil ; 146(6): 808-812, 2018 Jun.
Artigo em Espanhol | MEDLINE | ID: mdl-30148914

RESUMO

We report a 19 years old male presenting with knee pain, elevated liver enzymes and proteinuria. Further investigation found positive antinuclear and anti-smooth muscle antibodies and a liver biopsy revealed the presence of an autoimmune hepatitis. Treatment with corticosteroids and azathioprine was started, resulting in normalization of liver enzymes but proteinuria persisted and a kidney biopsy disclosed a focal segmental glomerulosclerosis. The use of lisinopril resulted in a significative reduction of proteinuria and, after 30 months of follow up, he continues with azathioprine, lisinopril and a low prednisone dose without evidence of liver or kidney disease activity.


Assuntos
Glomerulosclerose Segmentar e Focal/complicações , Hepatite Autoimune/complicações , Proteinúria/complicações , Autoimunidade , Diagnóstico Diferencial , Glomerulosclerose Segmentar e Focal/diagnóstico , Glomerulosclerose Segmentar e Focal/imunologia , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/imunologia , Humanos , Imuno-Histoquímica , Rim/patologia , Fígado/patologia , Masculino , Proteinúria/diagnóstico , Proteinúria/tratamento farmacológico , Proteinúria/imunologia , Adulto Jovem
8.
Rev. méd. Chile ; 146(6): 808-812, jun. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-961463

RESUMO

We report a 19 years old male presenting with knee pain, elevated liver enzymes and proteinuria. Further investigation found positive antinuclear and anti-smooth muscle antibodies and a liver biopsy revealed the presence of an autoimmune hepatitis. Treatment with corticosteroids and azathioprine was started, resulting in normalization of liver enzymes but proteinuria persisted and a kidney biopsy disclosed a focal segmental glomerulosclerosis. The use of lisinopril resulted in a significative reduction of proteinuria and, after 30 months of follow up, he continues with azathioprine, lisinopril and a low prednisone dose without evidence of liver or kidney disease activity.


Assuntos
Humanos , Masculino , Adulto Jovem , Proteinúria/complicações , Glomerulosclerose Segmentar e Focal/complicações , Hepatite Autoimune/complicações , Proteinúria/diagnóstico , Proteinúria/imunologia , Proteinúria/tratamento farmacológico , Imuno-Histoquímica , Glomerulosclerose Segmentar e Focal/diagnóstico , Glomerulosclerose Segmentar e Focal/imunologia , Autoimunidade , Hepatite Autoimune/diagnóstico , Hepatite Autoimune/imunologia , Diagnóstico Diferencial , Rim/patologia , Fígado/patologia
9.
J Am Coll Surg ; 224(5): 851-861, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28163089

RESUMO

BACKGROUND: The benefits of minimally invasive surgery (MIS) for low-risk or minor liver resection are well established. There is growing interest in MIS for major hepatectomy (MH) and other challenging resections, but there remain unanswered questions of safety that prevent broad adoption of this technique. STUDY DESIGN: We conducted a retrospective cohort study of patients undergoing hepatectomy at 65 hospitals participating in the NSQIP Hepatopancreatobiliary Collaborative in 2014. We assessed serious morbidity or mortality (SMM; including organ/space infection and organ failure). Secondary outcomes included transfusion, bile leak, liver failure, reoperation or intervention, and 30-day readmission. We also measured factors considered to make resection more challenging (ie large tumors, cirrhosis, ≥3 concurrent resections, previous neoadjuvant chemotherapy, and morbid obesity). RESULTS: There were 2,819 patients who underwent hepatectomy (aged 58 ± 14 years; 53% female; 25% had MIS). After adjusting for clinical and operative factors, the odds of SMM (odds ratio [OR] = 0.57; 95% CI 0.34 to 0.96; p = 0.03) and reoperation or intervention (OR = 0.52; 95% CI 0.29 to 0.93; p = 0.03) were significantly lower for patients undergoing MIS compared with open. In the MH group (n = 1,015 [13% MIS]), there was no difference in the odds of SMM after MIS (OR = 0.37; 95% CI 0.13 to 1.11; p = 0.08); however, minimally invasive MH met criteria for noninferiority. There were no differences in liver-specific complications or readmission between the groups. Odds of SMM were significantly lower after MIS among patients who had received neoadjuvant chemotherapy (OR = 0.33; 95% CI 0.15 to 0.70; p = 0.004). CONCLUSIONS: In this large study of minimally invasive MH, we found safety outcomes that are equivalent or superior to conventional open surgery. Although the decision to offer MIS might be influenced by factors not included in this evaluation (eg surgeon experience and other patient factors), these findings support its current use in MH.


Assuntos
Hepatectomia , Neoplasias Hepáticas/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos , Adulto , Idoso , Feminino , Humanos , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Obesidade Mórbida/complicações , Estudos Retrospectivos , Resultado do Tratamento
10.
Dig Dis Sci ; 61(11): 3190-3198, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27572941

RESUMO

BACKGROUND: Decreased muscle mass or sarcopenia has been associated with nonalcoholic fatty liver disease (NAFLD). However, the functional consequences of this association and its pathogenesis remain ill-defined. AIMS: To evaluate muscle mass and function in a diet-induced NAFLD mouse model and explore its association with changes in serum insulin-like growth factor-1 (IGF-1). METHODS: Weight gain, visceral fat, serum biochemical parameters, liver histology, and hepatic triglyceride content (HTC) were assessed in C57/Bl6 mice fed a westernized diet during 16 weeks. In addition, we determined muscle fiber size and strength of limb skeletal muscle, myosin heavy chain (MHC) protein levels, and IGF-1 serum levels. RESULTS: Westernized diet feeding was associated with weight gain, increased visceral fat mass (epididymal pad weight: 0.76 g ± 0.13 vs. 0.33 ± 0.27 g; p = 0.0023), hepatic steatosis (HTC: 118.2 ± 6.88 mg/g liver vs. 43.26 ± 5.63 mg/g<, p < 0.05), and necroinflammation (histological scores: 1.29 ± 0.42 vs. 4.00 ± 0.53<, p < 0.05). Also, mice fed the experimental diet had an increased proportion of low-diameter muscle fibers (0-30 µm) and a decreased proportion of high-diameter muscle fibers (60-90 µm), which correlated with decreased MHC protein levels, consistent with significant muscle atrophy. Functional studies showed that mice fed a westernized diet had reduced muscle strength and lower serum levels of IGF-1 (284.2 ± 20.04 pg/ml) compared with chow-fed mice (366.0 ± 12.42 pg/ml, p < 0.05). CONCLUSION: Experimental NAFLD is associated with sarcopenia, decreased muscle strength, and reduced IGF-1 serum levels. IGF-1 reduction may be involved in pathogenesis of NAFLD-associated sarcopenia.


Assuntos
Dieta Ocidental , Fator de Crescimento Insulin-Like I/metabolismo , Fígado/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Sarcopenia/metabolismo , Animais , Modelos Animais de Doenças , Gordura Intra-Abdominal , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fibras Musculares Esqueléticas/patologia , Força Muscular/fisiologia , Músculo Esquelético/patologia , Cadeias Pesadas de Miosina/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Sarcopenia/patologia , Sarcopenia/fisiopatologia , Triglicerídeos/metabolismo , Aumento de Peso
11.
World J Gastroenterol ; 20(47): 17709-26, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25548470

RESUMO

Bowel preparation is a core issue in colonoscopy, as it is closely related to the quality of the procedure. Patients often find that bowel preparation is the most unpleasant part of the examination. It is widely accepted that the quality of cleansing must be excellent to facilitate detecting neoplastic lesions. In spite of its importance and potential implications, until recently, bowel preparation has not been the subject of much study. The most commonly used agents are high-volume polyethylene glycol (PEG) electrolyte solution and sodium phosphate. There has been some confusion, even in published meta-analyses, regarding which of the two agents provides better cleansing. It is clear now that both PEG and sodium phosphate are effective when administered with proper timing. Consequently, the timing of administration is recognized as one of the central factors to the quality of cleansing. The bowel preparation agent should be administered, at least in part, a few hours in advance of the colonoscopy. Several low volume agents are available, and either new or modified schedules with PEG that usually improve tolerance. Certain adjuvants can also be used to reduce the volume of PEG, or to improve the efficacy of other agents. Other factors apart from the choice of agent can improve the quality of bowel cleansing. For instance, the effect of diet before colonoscopy has not been completely clarified, but an exclusively liquid diet is probably not required, and a low-fiber diet may be preferable because it improves patient satisfaction and the quality of the procedure. Some patients, such as diabetics and persons with heart or kidney disease, require modified procedures and certain precautions. Bowel preparation for pediatric patients is also reviewed here. In such cases, PEG remains the most commonly used agent. As detecting neoplasia is not the main objective with these patients, less intensive preparation may suffice. Special considerations must be made for patients with inflammatory bowel disease, including safety and diagnostic issues, so that the most adequate agent is chosen. Identifying neoplasia is one of the main objectives of colonoscopy with these patients, and the target lesions are often almost invisible with white light endoscopy. Therefore excellent quality preparation is required to find these lesions and to apply advanced methods such as chromoendoscopy. Bowel preparation for patients with lower gastrointestinal bleeding represents a challenge, and the strategies available are also reviewed here.


Assuntos
Catárticos/administração & dosagem , Colo/patologia , Doenças do Colo/diagnóstico , Colonoscopia , Fosfatos/administração & dosagem , Polietilenoglicóis/administração & dosagem , Irrigação Terapêutica/métodos , Administração Oral , Catárticos/efeitos adversos , Doenças do Colo/patologia , Esquema de Medicação , Jejum , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Adesão à Medicação , Educação de Pacientes como Assunto , Seleção de Pacientes , Fosfatos/efeitos adversos , Polietilenoglicóis/efeitos adversos , Valor Preditivo dos Testes , Fatores de Tempo
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