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1.
Med Teach ; 46(3): 330-336, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-37917988

RESUMO

Despite the numerous calls for integrating quality improvement and patient safety (QIPS) curricula into health professions education, there are limited examples of effective implementation for early learners. Typically, pre-clinical QIPS experiences involve lectures or lessons that are disconnected from the practice of medicine. Consequently, students often prioritize other content they consider more important. As a result, they may enter clinical settings without essential QIPS skills and struggle to incorporate these concepts into their early professional identity formation. In this paper, we present twelve tips aimed at assisting educators in developing QIPS education early in the curricula of health professions students. These tips address various key issues, including aligning incentives, providing longitudinal experiences, incorporating real-world care outcomes, optimizing learning environments, communicating successes, and continually enhancing education and care delivery processes.


Assuntos
Medicina , Estudantes de Ciências da Saúde , Humanos , Melhoria de Qualidade , Currículo , Aprendizagem
2.
J Lipid Res ; 64(1): 100305, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36273647

RESUMO

Hormone-sensitive lipase (HSL) plays a crucial role in intracellular lipolysis, and loss of HSL leads to diacylglycerol (DAG) accumulation, reduced FA mobilization, and impaired PPARγ signaling. Hsl knockout mice exhibit adipose tissue inflammation, but the underlying mechanisms are still not clear. Here, we investigated if and to what extent HSL loss contributes to endoplasmic reticulum (ER) stress and adipose tissue inflammation in Hsl knockout mice. Furthermore, we were interested in how impaired PPARγ signaling affects the development of inflammation in epididymal white adipose tissue (eWAT) and inguinal white adipose tissue (iWAT) of Hsl knockout mice and if DAG and ceramide accumulation contribute to adipose tissue inflammation and ER stress. Ultrastructural analysis showed a markedly dilated ER in both eWAT and iWAT upon loss of HSL. In addition, Hsl knockout mice exhibited macrophage infiltration and increased F4/80 mRNA expression, a marker of macrophage activation, in eWAT, but not in iWAT. We show that treatment with rosiglitazone, a PPARγ agonist, attenuated macrophage infiltration and ameliorated inflammation of eWAT, but expression of ER stress markers remained unchanged, as did DAG and ceramide levels in eWAT. Taken together, we show that HSL loss promoted ER stress in both eWAT and iWAT of Hsl knockout mice, but inflammation and macrophage infiltration occurred mainly in eWAT. Also, PPARγ activation reversed inflammation but not ER stress and DAG accumulation. These data indicate that neither reduction of DAG levels nor ER stress contribute to the reversal of eWAT inflammation in Hsl knockout mice.


Assuntos
PPAR gama , Esterol Esterase , Camundongos , Animais , Rosiglitazona/farmacologia , Esterol Esterase/genética , Esterol Esterase/metabolismo , Camundongos Knockout , PPAR gama/genética , PPAR gama/metabolismo , Tecido Adiposo/metabolismo , Tecido Adiposo Branco/metabolismo , Lipólise/fisiologia , Inflamação/tratamento farmacológico , Inflamação/genética , Inflamação/metabolismo
3.
Biotechnol Bioeng ; 119(6): 1467-1482, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35211957

RESUMO

The cyanobacterium Nostoc sp. BB 92.3. had shown antibacterial activity. A cultivation as biofilm, a self-forming matrix of cells and extracellular polymeric substances, increased the antibacterial effect. A new photobioreactor system was developed that allows a surface-associated cultivation of Nostoc sp. as biofilm. High-density polyethylene carriers operated as a moving bed were selected as surface for biomass immobilization. This system, well established in heterotrophic wastewater treatment, was for the first time used for phototrophic biofilms. The aim was a cultivation on a large scale without inhibiting growth while maximizing immobilization. Cultivation in a small photobioreactor (1.5 L) with different volumetric filling degrees of carriers (13.4%-53.8%) in a batch process achieved immobilization rates of 70%-85% and growth was similar to a no-carrier-control. In a larger photobioreactor (65 L) essentially all of the biomass was immobilized on the carriers and the space-time yield of biomass (0.018 gcell dry weight L-1 day- ​​​​​​​1 ) was competitive compared to phototrophic biofilm cultivations from literature. The use of carriers increased the gas exchange in the reactor by a factor of 2.5-3 but doubled the mixing time. Enriched gassing with carbon dioxide resulted in a short-term increase in growth rate, but unexpectedly it also adversely changed the growth morphology.


Assuntos
Nostoc , Fotobiorreatores , Antibacterianos , Biofilmes , Biomassa , Fotobiorreatores/microbiologia
4.
Aesthet Surg J ; 42(12): NP745-NP755, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-35724655

RESUMO

BACKGROUND: Autologous fat grafting is an effective tool for soft tissue augmentation in reconstructive breast surgery. Despite the major advantages of this minimally invasive approach, the unpredictability of graft survival presents challenges. OBJECTIVES: No clear consensus on the optimal technique has yet been published and well-defined prospective studies investigating impairing factors are lacking. This aim of this study was to generate valuable fundamental data. METHODS: Ten female patients undergoing elective autologous fat grafting after nipple-sparing mastectomy were enrolled. Punch biopsies and lipoaspirates were collected from the harvest site for histologic, gene expression, and scanning electron microscopic analysis. Noninvasive Lipometer measurements determining the subcutaneous adipose tissue thickness at the graft site were used to calculate the respective take rate. Patient- and surgery-related data were acquired and correlated with the take rate. RESULTS: A statistically relevant correlation between the take rate and the existing mean subcutaneous adipose tissue thickness at the grafted breast prior to surgery was observed. An approximate correlation was identified regarding the number of previous grafting sessions, body weight, and BMI. No statistically significant correlation was demonstrated for age, harvest site, or the mean adipocyte size. A lower level of cell damage was observed in scanning electron microscopic samples of washed lipoaspirates; and a strong indirect correlation with the expression of the adipocyte markers FABP4 and PLIN1 was apparent. CONCLUSIONS: Factors correlating to the take rate were identified. Future studies investigating the clinical relevance of each impairing factor are essential to contribute to the optimization of this valuable method.


Assuntos
Neoplasias da Mama , Mamoplastia , Humanos , Feminino , Mamoplastia/métodos , Mastectomia , Estudos Prospectivos , Tecido Adiposo/transplante , Transplante Autólogo/métodos , Sobrevivência de Enxerto
5.
Development ; 144(18): 3253-3263, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28827395

RESUMO

Asymmetric partitioning is an essential component of many developmental processes. As spermatogenesis concludes, sperm are streamlined by discarding unnecessary cellular components into cellular wastebags called residual bodies (RBs). During nematode spermatogenesis, this asymmetric partitioning event occurs shortly after anaphase II, and both microtubules and actin partition into a central RB. Here, we use fluorescence and transmission electron microscopy to elucidate and compare the intermediate steps of RB formation in Caenorhabditis elegans, Rhabditis sp. SB347 (recently named Auanema rhodensis) and related nematodes. In all cases, intact microtubules reorganize and move from centrosomal to non-centrosomal sites at the RB-sperm boundary whereas actin reorganizes through cortical ring expansion and clearance from the poles. However, in species with tiny spermatocytes, these cytoskeletal changes are restricted to one pole. Consequently, partitioning yields one functional sperm with the X-bearing chromosome complement and an RB with the other chromosome set. Unipolar partitioning may not require an unpaired X, as it also occurs in XX spermatocytes. Instead, constraints related to spermatocyte downsizing may have contributed to the evolution of a sperm cell equivalent to female polar bodies.


Assuntos
Divisão Celular Assimétrica , Caenorhabditis elegans/citologia , Tamanho Celular , Citoesqueleto/metabolismo , Razão de Masculinidade , Espermatozoides/citologia , Actinas/metabolismo , Animais , Centrossomo/metabolismo , Citoesqueleto/ultraestrutura , Feminino , Organismos Hermafroditas/citologia , Masculino , Meiose , Microtúbulos/metabolismo , Modelos Biológicos , Espermatócitos/citologia , Espermatócitos/ultraestrutura , Espermatogênese , Espermatozoides/ultraestrutura
6.
FASEB J ; 33(1): 1209-1225, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30169110

RESUMO

Statins, which reduce LDL-cholesterol by inhibition of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, are among the most widely prescribed drugs. Skeletal myopathy is a known statin-induced adverse effect associated with mitochondrial changes. We hypothesized that similar effects would occur in cardiac myocytes in a lipophilicity-dependent manner between 2 common statins: atorvastatin (lipophilic) and pravastatin (hydrophilic). Neonatal cardiac ventricular myocytes were treated with atorvastatin and pravastatin for 48 h. Both statins induced endoplasmic reticular (ER) stress, but only atorvastatin inhibited ERK1/2T202/Y204, AktSer473, and mammalian target of rapamycin signaling; reduced protein abundance of caveolin-1, dystrophin, epidermal growth factor receptor, and insulin receptor-ß; decreased Ras homolog gene family member A activation; and induced apoptosis. In cardiomyocyte-equivalent HL-1 cells, atorvastatin, but not pravastatin, reduced mitochondrial oxygen consumption. When male mice underwent atorvastatin and pravastatin administration per os for up to 7 mo, only long-term atorvastatin, but not pravastatin, induced elevated serum creatine kinase; swollen, misaligned, size-variable, and disconnected cardiac mitochondria; alteration of ER structure; repression of mitochondria- and endoplasmic reticulum-related genes; and a 21% increase in mortality in cardiac-specific vinculin-knockout mice during the first 2 months of administration. To our knowledge, we are the first to demonstrate in vivo that long-term atorvastatin administration alters cardiac ultrastructure, a finding with important clinical implications.-Godoy, J. C., Niesman, I. R., Busija, A. R., Kassan, A., Schilling, J. M., Schwarz, A., Alvarez, E. A., Dalton, N. D., Drummond, J. C., Roth, D. M., Kararigas, G., Patel, H. H., Zemljic-Harpf, A. E. Atorvastatin, but not pravastatin, inhibits cardiac Akt/mTOR signaling and disturbs mitochondrial ultrastructure in cardiac myocytes.


Assuntos
Atorvastatina/farmacologia , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Mitocôndrias Cardíacas/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Pravastatina/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular , LDL-Colesterol/sangue , Creatina Quinase/sangue , Masculino , Camundongos , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/ultraestrutura , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/metabolismo , Transcriptoma , Vinculina/genética , Proteína rhoA de Ligação ao GTP/metabolismo
7.
Int J Mol Sci ; 21(16)2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32796510

RESUMO

Autoimmune diabetes is a complex multifactorial disease with genetic and environmental factors playing pivotal roles. While many genes associated with the risk of diabetes have been identified to date, the mechanisms by which external triggers contribute to the genetic predisposition remain unclear. Here, we derived embryonic stem (ES) cell lines from diabetes-prone non-obese diabetic (NOD) and healthy C57BL/6 (B6) mice. While overall pluripotency markers were indistinguishable between newly derived NOD and B6 ES cells, we discovered several differentially expressed genes that normally are not expressed in ES cells. Several genes that reside in previously identified insulin-dependent diabetics (Idd) genomic regions were up-regulated in NOD ES cells. Gene set enrichment analysis showed that different groups of genes associated with immune functions are differentially expressed in NOD. Transcriptomic analysis of NOD blastocysts validated several differentially overexpressed Idd genes compared to B6. Genome-wide mapping of active histone modifications using ChIP-Seq supports active expression as the promoters and enhancers of activated genes are also marked by active histone modifications. We have also found that NOD ES cells secrete more inflammatory cytokines. Our data suggest that the known genetic predisposition of NOD to autoimmune diabetes leads to epigenetic instability of several Idd regions.


Assuntos
Autoimunidade/genética , Blastocisto/metabolismo , Sistema Imunitário/metabolismo , Células-Tronco Embrionárias Murinas/metabolismo , Transcrição Gênica , Animais , Quimiocinas/metabolismo , Cromatina/metabolismo , Diabetes Mellitus Experimental/genética , Epigênese Genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos NOD , Proteoma/metabolismo , Proteômica , Transcriptoma/genética
8.
Chemistry ; 25(24): 6119-6123, 2019 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-30866114

RESUMO

The direct generation of aldehydes from carboxylic acids is often a challenging synthetic task but undoubtedly attractive in view of abundant supply of such feedstocks from nature. Though long known, biocatalytic carboxylate reductions are at an early stage of development, presumably because of their co-factor requirement. To establish an alternative to whole-cell-based carboxylate reductions which are limited by side reactions, we developed an in vitro multi-enzyme system that allows for quantitative reductions of various carboxylic acids with full recycling of all cofactors and prevention of undesired over-reductions. Regeneration of adenosine 5'-triphosphate is achieved through the simultaneous action of polyphosphate kinases from Meiothermus ruber and Sinorhizobium meliloti and ß-nicotinamide adenine dinucleotide 2'-phosphate is reduced by a glucose dehydrogenase. Under these conditions and in the presence of the carboxylate reductases from Neurospora crassa or Nocardia iowensis, various aromatic, heterocyclic and aliphatic carboxylic acids were quantitatively reduced to the respective aldehydes.

9.
Proc Natl Acad Sci U S A ; 113(16): E2316-25, 2016 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-27044095

RESUMO

To study the development and function of "natural-arising" T regulatory (nTreg) cells, we developed a novel nTreg model on pure nonobese diabetic background using epigenetic reprogramming via somatic cell nuclear transfer. On RAG1-deficient background, we found that monoclonal FoxP3(+)CD4(+)Treg cells developed in the thymus in the absence of other T cells. Adoptive transfer experiments revealed that the thymic niche is not a limiting factor in nTreg development. In addition, we showed that the T-cell receptor (TCR) ß-chain of our nTreg model was not only sufficient to bias T-cell development toward the CD4 lineage, but we also demonstrated that this TCR ß-chain was able to provide stronger TCR signals. This TCR-ß-driven mechanism would thus unify former per se contradicting hypotheses of TCR-dependent and -independent nTreg development. Strikingly, peripheral FoxP3(-)CD4(+)T cells expressing the same TCR as this somatic cell nuclear transfer nTreg model had a reduced capability to differentiate into Th1 cells but were poised to differentiate better into induced nTreg cells, both in vitro and in vivo, representing a novel peripheral precursor subset of nTreg cells to which we refer to as pre-nTreg cells.


Assuntos
Diferenciação Celular/imunologia , Modelos Imunológicos , Técnicas de Transferência Nuclear , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Linfócitos T Reguladores/imunologia , Transferência Adotiva , Animais , Camundongos , Camundongos Knockout , Linfócitos T Reguladores/citologia
10.
Environ Sci Technol ; 52(2): 446-456, 2018 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-29185716

RESUMO

Here we report concentrations of pollutants in floating plastics from the North Pacific accumulation zone (NPAC). We compared chemical concentrations in plastics of different types and sizes, assessed ocean plastic potential risks using sediment quality criteria, and discussed the implications of our findings for bioaccumulation. Our results suggest that at least a fraction of the NPAC plastics is not in equilibrium with the surrounding seawater. For instance, "hard plastic" samples had significantly higher PBDE concentrations than "nets and ropes" samples, and 29% of them had PBDE composition similar to a widely used flame-retardant mixture. Our findings indicate that NPAC plastics may pose a chemical risk to organisms as 84% of the samples had at least one chemical exceeding sediment threshold effect levels. Furthermore, our surface trawls collected more plastic than biomass (180 times on average), indicating that some NPAC organisms feeding upon floating particles may have plastic as a major component of their diets. If gradients for pollutant transfer from NPAC plastic to predators exist (as indicated by our fugacity ratio calculations), plastics may play a role in transferring chemicals to certain marine organisms.


Assuntos
Poluentes Ambientais , Poluentes Químicos da Água , Organismos Aquáticos , Monitoramento Ambiental , Oceano Pacífico , Plásticos , Água do Mar
11.
Acta Neuropathol ; 134(2): 281-295, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28620692

RESUMO

Multiple sclerosis (MS) is a chronic autoimmune disease of the central nervous system (CNS) in young adults that has serious negative socioeconomic effects. In addition to symptoms caused by CNS pathology, the majority of MS patients frequently exhibit gastrointestinal dysfunction, which was previously either explained by the presence of spinal cord lesions or not directly linked to the autoimmune etiology of the disease. Here, we studied the enteric nervous system (ENS) in a B cell- and antibody-dependent mouse model of MS by immunohistochemistry and electron microscopy at different stages of the disease. ENS degeneration was evident prior to the development of CNS lesions and the onset of neurological deficits in mice. The pathology was antibody mediated and caused a significant decrease in gastrointestinal motility, which was associated with ENS gliosis and neuronal loss. We identified autoantibodies against four potential target antigens derived from enteric glia and/or neurons by immunoprecipitation and mass spectrometry. Antibodies against three of the target antigens were also present in the plasma of MS patients as confirmed by ELISA. The analysis of human colon resectates provided evidence of gliosis and ENS degeneration in MS patients compared to non-MS controls. For the first time, this study establishes a pathomechanistic link between the well-established autoimmune attack on the CNS and ENS pathology in MS, which might provide a paradigm shift in our current understanding of the immunopathogenesis of the disease with broad diagnostic and therapeutic implications.


Assuntos
Autoanticorpos/sangue , Gastroenteropatias/etiologia , Esclerose Múltipla , Animais , Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/patologia , Citocinas/metabolismo , Modelos Animais de Doenças , Sistema Nervoso Entérico/metabolismo , Sistema Nervoso Entérico/patologia , Sistema Nervoso Entérico/ultraestrutura , Feminino , Adjuvante de Freund/toxicidade , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Esclerose Múltipla/complicações , Esclerose Múltipla/imunologia , Esclerose Múltipla/patologia , Músculo Liso/patologia , Músculo Liso/ultraestrutura , Proteína Básica da Mielina/imunologia , Proteína Básica da Mielina/metabolismo , Proteína Básica da Mielina/toxicidade , Glicoproteína Mielina-Oligodendrócito/imunologia , Glicoproteína Mielina-Oligodendrócito/toxicidade , Plexo Mientérico/patologia , Plexo Mientérico/ultraestrutura , Proteínas Recombinantes de Fusão/imunologia , Proteínas Recombinantes de Fusão/toxicidade , Tubulina (Proteína)/metabolismo
12.
Am J Respir Cell Mol Biol ; 55(4): 602-612, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27254784

RESUMO

Myeloid cells are key factors in the progression of bronchopulmonary dysplasia (BPD) pathogenesis. Endothelial monocyte-activating polypeptide II (EMAP II) mediates myeloid cell trafficking. The origin and physiological mechanism by which EMAP II affects pathogenesis in BPD is unknown. The objective was to determine the functional consequences of elevated EMAP II levels in the pathogenesis of murine BPD and to investigate EMAP II neutralization as a therapeutic strategy. Three neonatal mouse models were used: (1) BPD (hyperoxia), (2) EMAP II delivery, and (3) BPD with neutralizing EMAP II antibody treatments. Chemokinic function of EMAP II and its neutralization were assessed by migration in vitro and in vivo. We determined the location of EMAP II by immunohistochemistry, pulmonary proinflammatory and chemotactic gene expression by quantitative polymerase chain reaction and immunoblotting, lung outcome by pulmonary function testing and histological analysis, and right ventricular hypertrophy by Fulton's Index. In BPD, EMAP II initially is a bronchial club-cell-specific protein-derived factor that later is expressed in galectin-3+ macrophages as BPD progresses. Continuous elevated expression corroborates with baboon and human BPD. Prolonged elevation of EMAP II levels recruits galectin-3+ macrophages, which is followed by an inflammatory state that resembles a severe BPD phenotype characterized by decreased pulmonary compliance, arrested alveolar development, and signs of pulmonary hypertension. In vivo pharmacological EMAP II inhibition suppressed proinflammatory genes Tnfa, Il6, and Il1b and chemotactic genes Ccl2 and Ccl9 and reversed the severe BPD phenotype. EMAP II is sufficient to induce macrophage recruitment, worsens BPD progression, and represents a targetable mechanism of BPD development.

13.
Int J Mol Sci ; 16(4): 8555-68, 2015 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-25894224

RESUMO

Lipolysis is the biochemical pathway responsible for the catabolism of cellular triacylglycerol (TG). Lipolytic TG breakdown is a central metabolic process leading to the generation of free fatty acids (FA) and glycerol, thereby regulating lipid, as well as energy homeostasis. The precise tuning of lipolysis is imperative to prevent lipotoxicity, obesity, diabetes and other related metabolic disorders. Here, we present our finding that miR-124a attenuates RNA and protein expression of the major TG hydrolase, adipose triglyceride lipase (ATGL/PNPLA2) and its co-activator comparative gene identification 58 (CGI-58/ABHD5). Ectopic expression of miR-124a in adipocytes leads to reduced lipolysis and increased cellular TG accumulation. This phenotype, however, can be rescued by overexpression of truncated Atgl lacking its 3'UTR, which harbors the identified miR-124a target site. In addition, we observe a strong negative correlation between miR-124a and Atgl expression in various murine tissues. Moreover, miR-124a regulates the expression of Atgl and Cgi-58 in murine white adipose tissue during fasting as well as the expression of Atgl in murine liver, during fasting and re-feeding. Together, these results point to an instrumental role of miR-124a in the regulation of TG catabolism. Therefore, we suggest that miR-124a may be involved in the regulation of several cellular and organismal metabolic parameters, including lipid storage and plasma FA concentration.


Assuntos
1-Acilglicerol-3-Fosfato O-Aciltransferase/genética , Lipase/genética , Lipólise , MicroRNAs/genética , Interferência de RNA , 1-Acilglicerol-3-Fosfato O-Aciltransferase/biossíntese , Regiões 3' não Traduzidas , Animais , Regulação Enzimológica da Expressão Gênica , Células HeLa , Humanos , Lipase/biossíntese , Camundongos
14.
Carcinogenesis ; 34(10): 2361-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23803690

RESUMO

Gemcitabine has limited clinical benefits in pancreatic ductal adenocarcinoma. The solvent-based traditional taxanes docetaxel and paclitaxel have not shown clinical results superior to gemcitabine. Nab-paclitaxel, a water-soluble albumin-bound paclitaxel, may carry superior distribution properties into the tumor microenvironment and has shown efficacy in multiple tumor types. We evaluated nab-paclitaxel effects compared with gemcitabine or docetaxel. For pancreatic ductal adenocarcinoma cells AsPC-1, BxPC-3, MIA PaCa-2 and Panc-1, gemcitabine IC50 ranged from 494nM to 23.9 µM; docetaxel IC50 range was from 5 to 34nM; nab-paclitaxel IC50 range was from 243nM to 4.9 µM. Addition of IC25 dose of docetaxel or nab-paclitaxel decreased gemcitabine IC50. Net tumor growth inhibition after gemcitabine, docetaxel or nab-paclitaxel was 67, 31 and 72%, which corresponded with intratumoral proliferative and apoptotic indices. Tumor stromal density was decreased by nab-paclitaxel and to a lesser extent by docetaxel as measured through reduction in α-smooth muscle actin, S100A4 and collagen 1 expression. Animal survival was prolonged after nab-paclitaxel treatment (41 days, P < 0.002) compared with gemcitabine (32 days, P = 0.005), docetaxel (32 days, P = 0.005) and controls (20 days). Survival in nab-paclitaxel/gemcitabine and docetaxel/gemcitabine sequential treatment groups was not superior to nab-paclitaxel alone. Low-dose combination of gemcitabine with nab-paclitaxel or docetaxel was more effective compared with controls or gemcitabine alone but not superior to regular dose nab-paclitaxel alone. Combination treatment of gemcitabine+nab-paclitaxel or gemcitabine+docetaxel increased gemcitabine concentration in plasma and tumor. The superior antitumor activity of nab-paclitaxel provides a strong rationale for considering nab-paclitaxel as first-line monotherapy in pancreatic ductal adenocarcinoma.


Assuntos
Antineoplásicos/farmacologia , Desoxicitidina/análogos & derivados , Neoplasias Experimentais/tratamento farmacológico , Paclitaxel/farmacologia , Neoplasias Pancreáticas/tratamento farmacológico , Taxoides/farmacologia , Paclitaxel Ligado a Albumina , Albuminas/administração & dosagem , Albuminas/farmacologia , Animais , Antineoplásicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacologia , Modelos Animais de Doenças , Docetaxel , Feminino , Humanos , Concentração Inibidora 50 , Neoplasias Experimentais/mortalidade , Neoplasias Experimentais/patologia , Paclitaxel/administração & dosagem , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Estatmina/metabolismo , Células Estromais/efeitos dos fármacos , Taxoides/administração & dosagem , Tubulina (Proteína)/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
15.
Sci Total Environ ; 905: 167020, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-37714343

RESUMO

Using biobased plastics has the potential to avoid fossil resource depletion and fossil CO2 emissions. Polylactic acid (PLA) is a fast-growing bio-based plastic made from fermented sugars. Nowadays, PLA is used to replace fossil-based polymers in healthcare and single-use applications, such as for packaging applications. However, PLA offers a much broader application range with the targeted use of a combination of its stereoisomers; PL(L)A and PL(D)A. A variety of these advanced grades of PLA can be used for multiple purposes in durable consumer products such as furniture. Recycling complex, mixed material and advanced grades of PLA is currently limited, as mechanical recycling has limitations in recycling mixed PLA grades. Using a depolymerization technology, products of such advanced grades of PLA can be recycled to form high-quality recycled PLA. A cradle-to-grave life cycle assessment study was executed to evaluate the sustainability of high-end durable product (a rug) with mixtures of PLA grade and the novel depolymerization technology. The findings of the study showed a 70 % reduction in CO2-eq. emissions compared to a conventionally designed rug. However, an increase is indicated in the following environmental impact categories: land use, eutrophication, and environmental toxicity. Sensitivity analyses for collection rates showcased that design for collection and recycling are key to obtaining a more sustainable biobased products. Additionally, scenario analysis supported depolymerization for PLA as recycling technology with low CO2-eq. emissions. Based on the results of the LCA and additional scenario analysis, the use of PLA is encouraged to be used in more durable and lasting products, such as furniture, from an environmental perspective, provided that the products are designed for collection and high-quality recycling to ensure material circularity.

16.
Adv Biochem Eng Biotechnol ; 183: 303-352, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36571615

RESUMO

Although the handling and exploitation of cyanobacteria is associated with some challenges, these phototrophic bacteria offer great opportunities for innovative biotechnological processes. This chapter covers versatile aspects of working with cyanobacteria, starting with up-to-date in silico and in vitro screening methods for bioactive substances. Subsequently, common conservation techniques and vitality/viability estimation methods are compared and supplemented by own data regarding the non-invasive vitality evaluation via pulse amplitude modulated fluorometry. Moreover, novel findings about the influence the state of the pre-cultures have on main cultures are presented. The following sub-chapters deal with different photobioreactor-designs, with special regard to biofilm photobioreactors, as well as with heterotrophic and mixotrophic cultivation modes. The latter topic provides information from literature on successfully enhanced cyanobacterial production processes, augmented by own data.


Assuntos
Cianobactérias , Biotecnologia , Fotobiorreatores/microbiologia
17.
Biomedicines ; 11(3)2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36979772

RESUMO

The skin serves as an important barrier protecting the body from physical, chemical and pathogenic hazards as well as regulating the bi-directional transport of water, ions and nutrients. In order to improve the knowledge on skin structure and function as well as on skin diseases, animal experiments are often employed, but anatomical as well as physiological interspecies differences may result in poor translatability of animal-based data to the clinical situation. In vitro models, such as human reconstructed epidermis or full skin equivalents, are valuable alternatives to animal experiments. Enormous advances have been achieved in establishing skin models of increasing complexity in the past. In this review, human skin structures are described as well as the fast evolving technologies developed to reconstruct the complexity of human skin structures in vitro.

18.
Biomedicines ; 11(4)2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-37189674

RESUMO

Skin wound healing is essential to health and survival. Consequently, high amounts of research effort have been put into investigating the cellular and molecular components involved in the wound healing process. The use of animal experiments has contributed greatly to the knowledge of wound healing, skin diseases, and the exploration of treatment options. However, in addition to ethical concerns, anatomical and physiological inter-species differences often influence the translatability of animal-based studies. Human in vitro skin models, which include essential cellular and structural components for wound healing analyses, would improve the translatability of results and reduce animal experiments during the preclinical evaluation of novel therapy approaches. In this review, we summarize in vitro approaches, which are used to study wound healing as well as wound healing-pathologies such as chronic wounds, keloids, and hypertrophic scars in a human setting.

19.
Curr Biol ; 32(10): 2334-2340.e3, 2022 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-35476937

RESUMO

Because of scaling issues, passive muscle and joint forces become increasingly important as limb size decreases.1-3 In some small limbs, passive forces can drive swing in locomotion,4,5 and antagonist passive torques help control limb swing velocity.6 In stance, minimizing antagonist muscle and joint passive forces could save energy. These considerations predict that, for small limbs, evolution would result in the angle range over which passive forces are too small to cause limb movement (called "resting-state range" in prior insect work4 and "area of neutral equilibrium" in physics and engineering) correlating with the limb's typical working range, usually that in locomotion. We measured the most protracted and retracted thorax-femur (ThF) angles of the pro- (front), meso- (middle), and metathoracic (hind) leg during stick insect (Carausius morosus) walks. This ThF working range differed in the three leg types, being more posterior in more posterior legs. In other experiments, we manually protracted or retracted the denervated front, middle, and hind legs. Upon release, passive forces moved the leg in the opposite direction (retraction or protraction) until it reached the most protracted or most retracted edge of the ThF resting-state range. The ThF resting-state angle ranges correlated with the leg-type working range, being more posterior in more posterior legs. The most protracted ThF walking angles were more retracted than the post-protraction ThF angles, and the most retracted ThF walking angles were similar to the post-retraction ThF angles. These correlations of ThF working- and resting-state ranges could simplify motor control and save energy. These data also provide an example of evolution altering behavior by changing passive muscle and joint properties.7.


Assuntos
Extremidades , Caminhada , Animais , Fenômenos Biomecânicos , Extremidades/fisiologia , Insetos/fisiologia , Locomoção/fisiologia , Extremidade Inferior/fisiologia , Torque
20.
Int J Disaster Risk Reduct ; 76: 103043, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35601394

RESUMO

At the onset of the COVID-19 pandemic, thousands of mutual aid groups were established on social media and operated as platforms through which people could offer or request social support. Considering the importance of Facebook mutual aid groups during the early stages of the COVID-19 pandemic in the United Kingdom but also the lack of empirical research regarding the trajectories and types of social support rendered available through the groups, our aims in this paper are threefold; first, to examine the trajectory of social support-related activity during the period between March-December 2020; second, to compare offers and requests of support during the peaks of the first and second waves; third to provide a rich analysis of the types of social support that were offered or requested through the online mutual aid groups. Quantitative findings suggest that online social support activity declined soon after the peak of the first pandemic wave and, at least in Facebook mutual aid groups, did not reach the levels observed during the first wave. Also, the number of offers of support during the first wave was higher compared to offers during the second wave, and similar was the case for requests for support. Additionally, offers for support were higher compared to requests for support during both the first and second waves. Finally, qualitative analysis showed that people used the Facebook mutual aid groups to offer and request various types of practical, emotional, and informational support. Limitations as well as implications of our study are considered.

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