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1.
Int J Mol Sci ; 24(2)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36675277

RESUMO

The pathogenesis of non-alcoholic fatty liver disease (NAFLD), the most prevalent chronic liver disease, is associated with zinc deficiency. Previous studies show zinc supplementation improves steatosis and glucose metabolism, but its therapeutic effects in patients with established NAFLD remain unclear. We developed an in vivo model to characterize the effects of zinc supplementation on high-fat diet (HFD) induced NAFLD and hypothesized that the established NAFLD would be attenuated by zinc supplementation. Male C57BL/6J mice were fed a control diet or HFD for 12 weeks. Mice were then further grouped into normal and zinc-supplemented diets for 8 additional weeks. Body composition and glucose tolerance were determined before and after zinc supplementation. At euthanasia, plasma and liver tissue were collected for characterization and downstream analysis. As expected, 12 weeks of HFD resulted in reduced glucose clearance and altered body composition. Eight weeks of subsequent zinc supplementation did not alter glucose handling, plasma transaminases, steatosis, or hepatic gene expression. Results from our model suggest 8-week zinc supplementation cannot reverse established NAFLD. The HFD may have caused NAFLD disease progression beyond rescue by an 8-week period of zinc supplementation. Future studies will address these limitations and provide insights into zinc as a therapeutic agent for established NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Masculino , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Dieta Hiperlipídica/efeitos adversos , Zinco/metabolismo , Camundongos Endogâmicos C57BL , Fígado/metabolismo , Suplementos Nutricionais , Glucose/metabolismo , Modelos Animais de Doenças
2.
Toxicol Appl Pharmacol ; 436: 115855, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34990729

RESUMO

Nonalcoholic fatty liver disease (NAFLD) is a major global public health concern affecting more than 25% of the world's population. Although obesity and diabetes are major risk factors for NAFLD, they cannot account for all cases, indicating the importance of other factors such as environmental exposures. Cadmium (Cd) exposure is implicated in the development of NAFLD; however, the influence of early life, in utero Cd exposure on the development of diet-induced NAFLD is poorly understood. Therefore, we developed an in vivo, multiple-hit model to study the effect of whole-life, low dose Cd exposure on high fat diet (HFD)-induced NAFLD. Adult male and female C57BL/6 J mice fed normal diets (ND) were exposed to 0, 0.5 or 5 ppm Cd-containing drinking water for 14 weeks before breeding. At weaning, offspring were fed ND or HFD and continued on the same drinking water regimen as their parents for 24 weeks. Cd exposure at different concentrations differentially altered HFD-associated adverse health effects, including liver injury. HFD-induced increased body weight, decreased glucose tolerance. Liver injury and lipid deposition were exacerbated by 5 ppm Cd exposure but attenuated by 0.5 ppm Cd exposure. Further, HFD blunted the response of metallothionein, a major Cd detoxification protein, in mice exposed to 5 ppm Cd but enhanced the response in mice exposed to 0.5 ppm Cd, suggesting a possible mechanism for Cd alteration of HFD-induced NAFLD. These results confirm the multi-hit nature of NAFLD and show whole life, low dose Cd exposure alters HFD-induced NAFLD with outcomes dependent on Cd concentration.


Assuntos
Cádmio/efeitos adversos , Fígado/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Animais , Dieta Hiperlipídica/métodos , Modelos Animais de Doenças , Feminino , Metabolismo dos Lipídeos/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos
3.
Toxicol Appl Pharmacol ; 457: 116294, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36283442

RESUMO

Hexavalent chromium [Cr(VI)] is a well-known and widespread environmental contaminant associated with a variety of adverse health effects, in particular lung cancer. The primary route of exposure in humans is through inhalation. Particulate forms of Cr(VI) are the most potent but in vivo studies are difficult. Intratracheal instillation requires highly trained surgical procedures which also limits the number of repeated exposures possible and thus requires high doses. Inhalation studies can deliver lower more chronic doses but are expensive and generate dangerous aerosols. We evaluated an oropharyngeal aspiration exposure route for zinc chromate particles in Wistar rats. Animals were treated once per week for 90 days. We found chromium accumulated in the lungs, blood, and reproductive tissues of all treated animals. Additionally, we found inflammatory indicators in the lung were elevated and circulating lymphocytes had increased chromosomal damage. These results show oropharyngeal aspiration provides a practicable exposure route for chronic and sub-chronic exposures of Cr(VI) particles.

4.
Toxicol Pathol ; 50(8): 930-941, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36377245

RESUMO

This article describes the Society of Toxicologic Pathology's (STP) five recommended ("best") practices for appropriate use of informed (non-blinded) versus masked (blinded) microscopic evaluation in animal toxicity studies intended for regulatory review. (1) Informed microscopic evaluation is the default approach for animal toxicity studies. (2) Masked microscopic evaluation has merit for confirming preliminary diagnoses for target organs and/or defining thresholds ("no observed adverse effect level" and similar values) identified during an initial informed evaluation, addressing focused hypotheses, or satisfying guidance or requests from regulatory agencies. (3) If used as the approach for an animal toxicity study to investigate a specific research question, masking of the initial microscopic evaluation should be limited to withholding only information about the group (control or test article-treated) and dose equivalents. (4) The decision regarding whether or not to perform a masked microscopic evaluation is best made by a toxicologic pathologist with relevant experience. (5) Pathology peer review, performed to verify the microscopic diagnoses and interpretations by the study pathologist, should use an informed evaluation approach. The STP maintains that implementing these five best practices has and will continue to consistently deliver robust microscopic data with high sensitivity for animal toxicity studies intended for regulatory review. Consequently, when conducting animal toxicity studies, the advantages of informed microscopic evaluation for maximizing sensitivity outweigh the perceived advantages of minimizing bias through masked microscopic examination.


Assuntos
Patologistas , Revisão por Pares , Animais , Humanos , Microscopia , Nível de Efeito Adverso não Observado
5.
Ecotoxicol Environ Saf ; 234: 113373, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35272187

RESUMO

As an environmental pollutant, cadmium (Cd) has been widely reported to induce male infertility due to its gonadotoxicity. However, the specific mechanism of Cd-induced testicular damage remains unclear. We investigated whether Cd causes testicular injury through ferroptosis. Male C57BL/6 J mice were exposed to 0, 0.5, or 5 ppm Cd via drinking water, starting in utero, and continuing through 24 weeks post-weaning. The results showed that Cd accumulated in the testes in a dose-dependent manner. Cd exposure at a concentration of 5 ppm, but not 0.5 ppm, caused a mass loss and detachment of germ cells, as well as a decreased meiotic index and testis weight. Exposure to 5 ppm Cd caused iron accumulation, increased levels of malondialdehyde (MDA) and nitro tyrosine (3-NT), and decreased expression of Nrf2, HO-1 and SOD2. We also found that exposure to 5 ppm Cd significantly decreased the expression of SLC7A11, a marker of ferroptosis in mice, along with the expression of SLC40A1 mRNA and ferritin heavy chain (FTH) protein, whereas there was no obvious change in the mRNA expression of Tfrc, ZIP8, ZIP14, and NCOA4. These findings indicate that 5 ppm Cd exposure increased testicular ferroptosis, which may be attributed to the reduction of stored iron export.

6.
Pain Med ; 22(2): 402-406, 2021 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-33164104

RESUMO

BACKGROUND: Colorectal cancer surgery is commonly performed with adequate analgesia essential for patient recovery. This study assessed the effectiveness of intrathecal morphine and patient-controlled analgesia (ITM + PCA) vs patient-controlled analgesia alone (PCA) for postoperative pain management in colorectal cancer surgery. METHODS: This retrospective study extracted and analyzed data covering a 4-year period (2014-2018) from a clinical database with 24- and 48-hour postsurgery follow-up. Primary outcomes included pain scores, median opioid consumption (oral morphine equivalence dose), sedation, nausea and vomiting, and length of admission. Outcomes were analyzed for ITM + PCA vs PCA alone, overall and stratified by laparotomy or laparoscopy procedures. RESULTS: In total, 283 patients were included: ITM + PCA (163) and PCA alone (120). Median opioid consumption in the first 24 hours for ITM + PCA vs PCA alone was lower for laparotomy (-32.7 mg, P<0.001) and laparoscopy (-14.3 mg, P<0.001). Median pain score (worst pain) within the first 24 hours for ITM + PCA vs PCA alone was similar for laparotomy (P>0.05) and lower for laparoscopy (-1 unit, P=0.031). Sedation occurred less frequently for ITM + PCA vs PCA at 24 hours (3.5% vs 11.4%, P=0.031), with nonsignificant reduction at 48 hours (4.8% vs 18.8%, P=0.090) for laparotomy, but with no difference for laparoscopy (P>0.05). Incidence of nausea and vomiting and length of admission were similar for ITM + PCA vs PCA alone for laparotomy or laparoscopy (P>0.05). CONCLUSION: This retrospective study demonstrated that ITM + PCA can achieve similar analgesic effects after laparotomy and laparoscopy colorectal cancer surgery compared with PCA alone while resulting in a reduction of oral opioid consumption and lower incidence of sedation.


Assuntos
Neoplasias Colorretais , Morfina , Analgesia Controlada pelo Paciente , Analgésicos Opioides/uso terapêutico , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/cirurgia , Humanos , Injeções Espinhais , Morfina/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Estudos Retrospectivos
7.
Genomics ; 112(2): 1096-1104, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31247332

RESUMO

Hymenopteran parasitoid wasps are a diverse collection of species that infect arthropod hosts and use factors found in their venoms to manipulate host immune responses, physiology, and behaviour. Whole parasitoid venoms have been profiled using proteomic approaches, and here we present a bioinformatic characterization of the venom protein content from Ganaspis sp. 1, a parasitoid that infects flies of the genus Drosophila. We find evidence that diverse evolutionary processes including multifunctionalization, co-option, gene duplication, and horizontal gene transfer may be acting in concert to drive venom gene evolution in Ganaspis sp.1. One major role of parasitoid wasp venom is host immune evasion. We previously demonstrated that Ganaspis sp. 1 venom inhibits immune cell activation in infected Drosophila melanogaster hosts, and our current analysis has uncovered additional predicted virulence functions. Overall, this analysis represents an important step towards understanding the composition and activity of parasitoid wasp venoms.


Assuntos
Venenos de Artrópodes/genética , Evolução Molecular , Vespas/genética , Animais , Venenos de Artrópodes/metabolismo , Drosophila melanogaster/imunologia , Drosophila melanogaster/parasitologia , Duplicação Gênica , Transferência Genética Horizontal , Evasão da Resposta Imune , Proteoma/genética , Proteoma/metabolismo , Vespas/patogenicidade
8.
Scott Med J ; 66(2): 73-76, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33573510

RESUMO

INTRODUCTION: Horse riding carries risk of injury which can result in fatality. The majority of published literature describes major trauma centre experience. We aimed to characterise injury patterns following equine trauma at a Scottish district general hospital. METHODS: A retrospective review of admissions following equine trauma was undertaken from 2014 to 2019. Mechanism and nature of injuries were noted. Patient management and outcomes were recorded and analysed to determine correlation. RESULTS: Of the 162 patients identified, 121 (74.7 per cent) were female. The commonest mechanism and injury sustained were falling from a horse (86.4 per cent) and head injury (17.9 per cent) respectively. Forty-four (27.2 per cent) had multiple injuries identified. Being crushed or kicked resulted in more abdominal visceral injuries (22.7 vs 0.7 per cent, p = <0.05) and ITU admissions (18.2 vs 6.4 per cent, p = 0.06) when compared with falling from alone. Eight (4.9 per cent) required transfer to a major trauma centre and 30-day mortality was 0.6 per cent. CONCLUSION: Although variable, injuries following equine trauma can be life threatening. Increased awareness and development of safety legislation is needed. In addition, research could be directed at assessing functional outcomes given the large number of orthopaedic injuries.


Assuntos
Acidentes por Quedas/estatística & dados numéricos , Traumatismos em Atletas/epidemiologia , Traumatismos Craniocerebrais/epidemiologia , Adulto , Animais , Traumatismos em Atletas/etiologia , Traumatismos Craniocerebrais/etiologia , Feminino , Cavalos , Hospitalização/estatística & dados numéricos , Hospitais de Distrito/estatística & dados numéricos , Humanos , Escala de Gravidade do Ferimento , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Reino Unido/epidemiologia
9.
Genome Res ; 27(4): 613-625, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28179366

RESUMO

Drug resistance is an almost inevitable consequence of cancer therapy and ultimately proves fatal for the majority of patients. In many cases, this is the consequence of specific gene mutations that have the potential to be targeted to resensitize the tumor. The ability to uniformly saturate the genome with point mutations without chromosome or nucleotide sequence context bias would open the door to identify all putative drug resistance mutations in cancer models. Here, we describe such a method for elucidating drug resistance mechanisms using genome-wide chemical mutagenesis allied to next-generation sequencing. We show that chemically mutagenizing the genome of cancer cells dramatically increases the number of drug-resistant clones and allows the detection of both known and novel drug resistance mutations. We used an efficient computational process that allows for the rapid identification of involved pathways and druggable targets. Such a priori knowledge would greatly empower serial monitoring strategies for drug resistance in the clinic as well as the development of trials for drug-resistant patients.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Genoma Humano , Acúmulo de Mutações , Taxa de Mutação , Linhagem Celular Tumoral , Humanos , Modelos Genéticos , Mutação Puntual
10.
Toxicol Appl Pharmacol ; 403: 115161, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32721433

RESUMO

Cadmium is a ubiquitous, non-essential metal that has earned a spot on the World Health Organizations top 10 chemicals of major public health concern. The mechanisms of cadmium-induced adverse health outcomes, such as cardiovascular disease, renal toxicity and cancer, are well studied in adults. However, the implications for early life exposures to low-level cadmium leading to increased risk of developing diseases in adulthood remains elusive. Epidemiological investigation of the long term implications of cadmium-associated adverse birth outcomes are limited and studies do not extend into adulthood. This review will summarize the literature on the non-lethal, adverse health effects associated with prenatal and early life exposure to cadmium and the implications of these exposures in the development of diseases later in life. In addition, this review will highlight possible mechanisms responsible for these outcomes as well as address the inconsistencies in the literature. More recent studies have addressed sex as a biological variable, showing prenatal cadmium exposure elicits sex-specific outcomes that would otherwise be masked by pooling male and female data. Furthermore, researchers have begun to investigate the role of prenatal and early life cadmium exposures in the development of diet-induced diseases with evidence of altered essential metal homeostasis as a likely mechanism for cadmium-enhanced, diet-induced diseases. Although novel experimental models are beginning to be established to study the association between prenatal cadmium exposure and adverse health outcomes in adulthood, the studies are few, highlighting a major need for further investigation.


Assuntos
Cádmio/toxicidade , Poluentes Ambientais/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Epigênese Genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Humanos , Gravidez
11.
Toxicol Pathol ; 48(4): 549-559, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32347786

RESUMO

The Society of Toxicologic Pathology (STP) explored current institutional practices for selecting between non-blinded versus blinded histopathologic evaluation during Good Laboratory Practice (GLP)-compliant, regulatory-type animal toxicity studies using a multi-question survey and STP-wide discussion (held at the 2019 STP annual meeting). Survey responses were received from 107 individuals representing 83 institutions that collectively employ 589 toxicologic pathologists. Most responses came from industry (N = 46, mainly biopharmaceutical or contract research organizations) and consultants (N = 24). For GLP-compliant animal toxicity studies, histopathologic evaluation usually involves initial (primary) non-blinded analysis, with post hoc informal blinded re-examination at the study pathologist's discretion to confirm subtle findings or establish thresholds. Initial blinded histopathologic evaluation sometimes is chosen by study pathologists to test formal hypotheses and/or by sponsors to address non-pathologist expectations about histopathology data objectivity. Current practice is that a blinded histopathologic evaluation is documented only if formal blinding (ie, using slides with coded labels) is employed, using simple statements without detailed methodology in the study protocol (or an amendment) and/or pathology report. Blinding is not an appropriate strategy for the initial histopathologic evaluation performed during pathology peer reviews of GLP-compliant animal toxicity studies. [Box: see text].


Assuntos
Testes de Toxicidade/métodos , Animais , Animais de Laboratório , Humanos , Patologistas , Patologia/métodos , Revisão por Pares , Projetos de Pesquisa , Inquéritos e Questionários , Toxicologia/métodos
12.
Phys Chem Chem Phys ; 22(6): 3314-3328, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-31971189

RESUMO

Diarylperfluorocyclopentenes are a well-characterized class of molecular photoswitches that undergo reversible photocyclization. The efficiency of cycloreversion (<∼30%), in particular, is known to be limited by a competition with excited-state deactivation by internal conversion that is strongly impacted by the electron-withdrawing/donating character of pendant aryl groups. Here we present a first study to determine how varied structural motifs for the core bridge group impact excited-state dynamics that control cycloreversion quantum yields. Specifically, we compare photophysical behaviors of 3,3'-(perfluorocyclopent-1-ene-1,2-diyl)bis(2-methylbenzo[b]thiophene) with diarylethene derivatives possessing the same benzo[b]thiophene pendant group but with a rigid 1-methyl-1H-pyrrole-2,5-dione and a rigid/aromatic thieno[3,4-b]thiophene bridge (TT) core bridge group. We find that the flexible perfluorocyclopentene core undergoes cycloreversion 3-4× slower than the rigid core photoswitches (9 vs. 2-3 ps in acetonitrile, 25 vs. 5-6 ps in cyclohexane) despite comparable cycloreversion quantum yields. To distinguish effects induced by bridge vs. pendant groups, we also studied a series of photoswitches with the same thieno[3,4-b]thiophene bridging group, but with varied pendant groups including 2,5-dimethylthiophene and 2-(3,5-bis(trifluoromethyl)phenyl)-5-methylthiophene. Analysis of temperature-dependent excited-state lifetimes and cycloreversion quantum yields reveals that both the rates of nonreactive internal conversion and reactive cycloreversion increase with greater structural rigidity of the core. This difference is attributed to smaller energy barriers on the excited-state potential energy surface for both reactive and non-reactive deactivation from the 21A electronic state relative to the flexible perfluorocyclopentene switch, implying that a rigid core results in a net shallower excited-state potential energy surface.

13.
Pain Med ; 21(12): 3451-3457, 2020 12 25.
Artigo em Inglês | MEDLINE | ID: mdl-32594139

RESUMO

OBJECTIVE: Chronic neuropathic pain is a common symptom in multiple sclerosis (MS). This randomized controlled single-blinded study investigated whether a new protocol involving five days of transcranial direct current stimulation (tDCS) with an interval period would be effective to reduce pain using the visual analog scale (VAS). Other secondary outcomes included the Neuropathic Pain Scale (NPS), Depression Anxiety Stress Score (DASS), Short Form McGill Pain Questionnaire (SFMPQ), and Multiple Sclerosis Quality of Life 54 (MSQOL54). DESIGN: A total of 30 participants were recruited for the study, with 15 participants randomized to a sham group or and 15 randomized to an active group. After a five-day course of a-tDCS, VAS and NPS scores were measured daily and then weekly after treatment up to four weeks after treatment. Secondary outcomes were measured pretreatment and then weekly up to four weeks. RESULTS: After a five-day course of a-tDCS, VAS scores were significantly reduced compared with sham tDCS and remained significantly low up to week 2 post-treatment. There were no statistically significant mean changes in MSQOL54, SFMPQ, NPS, or DASS for the sham or treatment group before treatment or at four-week follow-up. CONCLUSIONS: This study shows that repeated stimulation with a-tDCS for five days can reduce pain intensity for a prolonged period in patients with MS who have chronic neuropathic pain.


Assuntos
Esclerose Múltipla , Neuralgia , Estimulação Transcraniana por Corrente Contínua , Método Duplo-Cego , Humanos , Esclerose Múltipla/complicações , Esclerose Múltipla/terapia , Neuralgia/etiologia , Neuralgia/terapia , Medição da Dor , Qualidade de Vida
14.
Regul Toxicol Pharmacol ; 113: 104648, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32240713

RESUMO

The novel self-amplifying mRNA (SAM) technology for vaccines consists of an engineered replication-deficient alphavirus genome encoding an RNA-dependent RNA polymerase and the gene of the target antigen. To validate the concept, the rabies glycoprotein G was chosen as antigen. The delivery system for this vaccine was a cationic nanoemulsion. To characterize the local tolerance, potential systemic toxicity and biodistribution of this vaccine, two nonclinical studies were performed. In the repeated dose toxicity study, the SAM vaccine was administered intramuscularly to rats on four occasions at two-week intervals followed by a four-week recovery period. SAM-related changes consisted of a transient increase in neutrophil count, alpha-2-macroglobulin and fibrinogen levels. Transient aspartate aminotransferase and alanine aminotransferase increases were also noted in females only. At necropsy, observations related to the elicited inflammatory reaction, such as enlargement of the draining lymph nodes were observed that were almost fully reversible by the end of the recovery period. In the biodistribution study, rats received a single intramuscular injection of SAM vaccine and then were followed until Day 60. Rabies RNA was found at the injection sites and in the draining lymph nodes one day after administration, then generally decreased in these tissues but remained detectable up to Day 60. Rabies RNA was also transiently found in blood, lungs, spleen and liver. No microscopic changes in the brain and spinal cord were recorded. In conclusion, these results showed that the rabies SAM vaccine was well-tolerated by the animals and supported the clinical development program.


Assuntos
RNA Mensageiro/farmacocinética , Vacina Antirrábica/farmacocinética , Animais , Feminino , Injeções Intramusculares , Masculino , RNA Mensageiro/administração & dosagem , Vacina Antirrábica/administração & dosagem , Ratos , Ratos Sprague-Dawley , Medição de Risco , Distribuição Tecidual
15.
Chem Res Toxicol ; 32(6): 1070-1081, 2019 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-30912652

RESUMO

Childhood obesity, which is prevalent in developed countries, is a metabolic risk factor for cardiovascular disease. Cadmium (Cd), a ubiquitous environmental toxic metal, also has deleterious effects on the cardiovascular system. However, the combined effects of a high-fat diet (HFD) and lifelong, low-dose Cd exposure on cardiac remodeling remain unclear. This study aims to determine the effects of combined HFD and Cd exposure on cardiac remodeling, as well as gender-specific differences in the response. C57BL/6J mice were exposed to Cd at a low dose (L-Cd, 0.5 ppm) or high dose (H-Cd, 5 ppm) via drinking water from conception to sacrifice. After being weaned, the offspring mice were fed with a HFD (42% kcal from fat) for an additional 10 weeks. H-Cd exposure significantly increased Cd accumulation in the hearts of both parents and their offspring; a HFD showed no added effects on cardiac Cd content. H-Cd exposure increased cardiac metallothionein protein levels only in female mice, regardless of dietary intake. Histological analysis revealed that H-Cd exposure combined with a HFD induced cardiac hypertrophy and fibrosis only in female mice. This was further supported by elevated expression of ANP and COL1A1 protein levels along with COL1A1, COL1A2, and COL3A1 mRNA levels. Profibrotic markers PAI-1, CTGF, and FN were also elevated in HFD/H-Cd-exposed female mice. Levels of the oxidative stress marker 3-NT significantly increased in the hearts of HFD-fed female mice, whereas Cd exposure showed no additional effects. Of all the antioxidant markers examined, levels of CAT significantly increased in mice fed a HFD, regardless of gender and Cd exposure. In summary, a HFD combined with lifelong, low-dose Cd exposure induces cardiac hypertrophy and fibrosis in female but not male mice, a response that is independent of oxidative stress.


Assuntos
Cádmio/administração & dosagem , Cádmio/toxicidade , Cardiomegalia/induzido quimicamente , Dieta Hiperlipídica/efeitos adversos , Fibrose/induzido quimicamente , Animais , Cardiomegalia/patologia , Relação Dose-Resposta a Droga , Feminino , Fibrose/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos , Fatores Sexuais , Fatores de Tempo
16.
Phys Chem Chem Phys ; 21(26): 14440-14452, 2019 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-30920561

RESUMO

Bis(bithienyl)-1,2-dicyanoethene (4TCE) is a photoswitch that operates via reversible E/Z photoisomerization following absorption of visible light. cis-to-trans photoisomerization of 4TCE requires excitation below 470 nm, is relatively inefficient (quantum yield < 5%) and occurs via the lowest-lying triplet. We present excitation-wavelength dependent (565-420 nm) transient absorption (TA) studies to probe the photophysics of cis-to-trans isomerization to identify sources of switching inefficiency. TA data reveals contributions from more than one switch conformer and relaxation cascades between multiple states. Fast (∼4 ps) and slow (∼40 ps) components of spectral dynamics observed at low excitation energies (>470 nm) are readily attributed to deactivation of two conformers; this assignment is supported by computed thermal populations and absorption strengths of two molecular geometries (PA and PB) characterized by roughly parallel dipoles for the thiophenes on opposite sides of the ethene bond. Only the PB conformer is found to contribute to triplet population and the switching of cis-4TCE: high-energy excitation (<470 nm) of PB involves direct excitation to S2, relaxation from which prepares an ISC-active S1 geometry (ISC QY 0.4-0.67, kISC∼ 1.6-2.6 × 10-9 s-1) that is the gateway to triplet population and isomerization. We ascribe low cis-to-trans isomerization yield to excitation of the nonreactive PA conformer (75-85% loss) as well as loses along the PB S2→ S1→ T1 cascade (10-20% loss). In contrast, electrocyclization is inhibited by the electronic character of the excited states, as well as a non-existent thermal population of a reactive "antiparallel" ring conformation.

17.
Cochrane Database Syst Rev ; 12: CD012622, 2018 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-30567012

RESUMO

BACKGROUND: Chronic pain is common and significantly impacts on the lives of persons with multiple sclerosis (pwMS). Various types of non-pharmacological interventions are widely used, both in hospital and ambulatory/mobility settings to improve pain control in pwMS, but the effectiveness and safety of many non-pharmacological modalities is still unknown. OBJECTIVES: This review aimed to investigate the effectiveness and safety of non-pharmacological therapies for the management of chronic pain in pwMS. Specific questions to be addressed by this review include the following.Are non-pharmacological interventions (unidisciplinary and/or multidisciplinary rehabilitation) effective in reducing chronic pain in pwMS?What type of non-pharmacological interventions (unidisciplinary and/or multidisciplinary rehabilitation) are effective (least and most effective) and in what setting, in reducing chronic pain in pwMS? SEARCH METHODS: A literature search was performed using the specialised register of the Cochrane MS and Rare Diseases of the Central Nervous System Review Group, using the Cochrane MS Group Trials Register which contains CENTRAL, MEDLINE, Embase, CINAHL, LILACUS, Clinical trials.gov and the World Health Organization International Clinical Trials Registry Platform on 10 December 2017. Handsearching of relevant journals and screening of reference lists of relevant studies was carried out. SELECTION CRITERIA: All published randomised controlled trials (RCTs)and cross-over studies that compared non-pharmacological therapies with a control intervention for managing chronic pain in pwMS were included. Clinical controlled trials (CCTs) were eligible for inclusion. DATA COLLECTION AND ANALYSIS: All three review authors independently selected studies, extracted data and assessed the methodological quality of the studies using the Grades of Recommendation, Assessment, Development and Evaluation (GRADE) tool for best-evidence synthesis. Pooling data for meta-analysis was not possible due to methodological, clinical and statistically heterogeneity of the included studies. MAIN RESULTS: Overall, 10 RCTs with 565 participants which investigated different non-pharmacological interventions for the management of chronic pain in MS fulfilled the review inclusion criteria. The non-pharmacological interventions evaluated included: transcutaneous electrical nerve stimulation (TENS), psychotherapy (telephone self-management, hypnosis and electroencephalogram (EEG) biofeedback), transcranial random noise stimulation (tRNS), transcranial direct stimulation (tDCS), hydrotherapy (Ai Chi) and reflexology.There is very low-level evidence for the use of non-pharmacological interventions for chronic pain such as TENS, Ai Chi, tDCS, tRNS, telephone-delivered self-management program, EEG biofeedback and reflexology in pain intensity in pwMS. Although there were improved changes in pain scores and secondary outcomes (such as fatigue, psychological symptoms, spasm in some interventions), these were limited by methodological biases within the studies. AUTHORS' CONCLUSIONS: Despite the use of a wide range of non-pharmacological interventions for the treatment of chronic pain in pwMS, the evidence for these interventions is still limited or insufficient, or both. More studies with robust methodology and greater numbers of participants are needed to justify the effect of these interventions for the management of chronic pain in pwMS.


Assuntos
Dor Crônica/terapia , Esclerose Múltipla/complicações , Dor Musculoesquelética/terapia , Terapia por Exercício/métodos , Humanos , Hidroterapia , Hipnose , Massagem , Neurorretroalimentação , Educação de Pacientes como Assunto/métodos , Psicoterapia , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Terapia de Relaxamento , Estimulação Transcraniana por Corrente Contínua , Estimulação Elétrica Nervosa Transcutânea/métodos
18.
J Phys Chem A ; 119(50): 11989-96, 2015 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-26015078

RESUMO

Eumelanin is a naturally synthesized ultraviolet light absorbing biomolecule, possessing both photoprotective and phototoxic properties. We infer insight into these properties of eumelanin using a bottom-up approach, by investigating an ultraviolet absorbing motif of eumelanin, 4-tert-butylcatechol. Utilizing a combination of femtosecond transient electronic absorption spectroscopy and time-resolved velocity map ion imaging, our results suggest an environmental-dependent relaxation pathway, following irradiation at 267 nm to populate the S1 ((1)ππ*) state. Gas-phase and nonpolar solution-phase measurements reveal that the S1 state decays primarily through coupling onto the S2 ((1)πσ*) state which is dissociative along the nonintramolecular hydrogen bonded "free" O-H bond. This process occurs in 4.9 ± 0.6 ps in the gas-phase and 18 ± 1 ps in the nonpolar cyclohexane solution. Comparative studies on the deuterated isotopologue of 4-tert-butylcatechol in both the gas- and solution-phase (cyclohexane) reveal kinetic isotope effects of ∼19 and ∼4, respectively, supportive of O-H dissociation along a barriered pathway, and potentially mediated by quantum tunneling. In contrast, in the polar solvent acetonitrile, the S1 state decays on a much longer time scale of 1.7 ± 0.1 ns. We propose that the S1 decay is now multicomponent, driven by internal conversion, intersystem crossing, and fluorescence, as well as O-H dissociation. The attribution of conformer-driven excited state dynamics to explain how the S1 state decays in the gas- and nonpolar solution-phase versus the polar solution-phase, demonstrates the influence the environment can have on the ensuing excited state dynamics.


Assuntos
Catecóis/química , Processos Fotoquímicos , Gases , Modelos Moleculares , Estrutura Molecular , Soluções
19.
Invest New Drugs ; 32(5): 825-37, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24919854

RESUMO

The G1 restriction point is critical for regulating the cell cycle and is controlled by the Rb pathway (CDK4/6-cyclin D1-Rb-p16/ink4a). This pathway is important because of its inactivation in a majority of human tumors. Transition through the restriction point requires phosphorylation of retinoblastoma protein (Rb) by CDK4/6, which are highly validated cancer drug targets. We present the identification and characterization of a potent CDK4/6 inhibitor, LY2835219. LY2835219 inhibits CDK4 and CDK6 with low nanomolar potency, inhibits Rb phosphorylation resulting in a G1 arrest and inhibition of proliferation, and its activity is specific for Rb-proficient cells. In vivo target inhibition studies show LY2835219 is a potent inhibitor of Rb phosphorylation, induces a complete cell cycle arrest and suppresses expression of several Rb-E2F-regulated proteins 24 hours after a single dose. Oral administration of LY2835219 inhibits tumor growth in human tumor xenografts representing different histologies in tumor-bearing mice. LY2835219 is effective and well tolerated when administered up to 56 days in immunodeficient mice without significant loss of body weight or tumor outgrowth. In calu-6 xenografts, LY2835219 in combination with gemcitabine enhanced in vivo antitumor activity without a G1 cell cycle arrest, but was associated with a reduction of ribonucleotide reductase expression. These results suggest LY2835219 may be used alone or in combination with standard-of-care cytotoxic therapy. In summary, we have identified a potent, orally active small-molecule inhibitor of CDK4/6 that is active in xenograft tumors. LY2835219 is currently in clinical development.


Assuntos
Aminopiridinas/farmacologia , Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , Quinase 4 Dependente de Ciclina/antagonistas & inibidores , Quinase 6 Dependente de Ciclina/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Aminopiridinas/uso terapêutico , Animais , Antineoplásicos/uso terapêutico , Benzimidazóis/uso terapêutico , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Desoxicitidina/uso terapêutico , Quimioterapia Combinada , Feminino , Pontos de Checagem da Fase G1 do Ciclo Celular/efeitos dos fármacos , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Neoplasias/patologia , Fosforilação/efeitos dos fármacos , Inibidores de Proteínas Quinases/uso terapêutico , Proteína do Retinoblastoma/antagonistas & inibidores , Proteína do Retinoblastoma/metabolismo , Carga Tumoral/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto , Gencitabina
20.
Ann Pharmacother ; 48(6): 674-82, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24662112

RESUMO

PURPOSE: Obesity is a growing epidemic leading to worldwide public health concerns. Bariatric surgery is an option for patients with a body mass index (BMI) >40 kg/m(2) or BMI of >35 kg/m(2) with serious comorbid conditions. This meta-analysis examines the effect of bariatric surgery on the improvement or resolution of hypertension. METHODS: Two independent investigators conducted a literature search of PubMed (1990-2013) and Cochrane databases using the terms bariatric surgery and hypertension to identify appropriate human adult studies published in English. Studies were included if they reported the number of patients with hypertension prior to undergoing any bariatric surgery procedure and whether the hypertension improved or resolved postsurgery. The number of patients with hypertension and their response rates were extracted and analyzed using RevMan 5.2.5. RESULTS: In all, 31 prospective and 26 retrospective studies met all criteria. The types of bariatric surgery performed included Roux-en-Y, gastric banding, laparoscopic adjustable gastric banding, vertical gastric banding, sleeve gastrectomy, duodenal switch, and biliopancreatic diversion. The time to first follow-up after surgery varied from 1 week to 7 years. Of the 57 studies, 32 reported improvement of hypertension in 32 628 of 51 241 patients (odds ratio [OR] = 13.24; 95% CI = 7.73, 22.68; P < 0.00001); 46 studies reported the resolution of hypertension in 24 902 of 49 844 patients (OR = 1.70; 95% CI = 1.13, 2.58; P = 0.01). A random-effects model was used because the heterogeneity between the studies was high (I (2) = 97%). CONCLUSION: The results of this meta-analysis indicate that patients who undergo bariatric surgery experience improvement and resolution of their hypertension.


Assuntos
Cirurgia Bariátrica , Hipertensão/cirurgia , Obesidade/cirurgia , Adulto , Humanos , Hipertensão/epidemiologia , Obesidade/epidemiologia
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