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1.
Crit Care ; 27(1): 236, 2023 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-37322546

RESUMO

BACKGROUND: Sepsis is common, deadly, and heterogenous. Prior analyses of patients with sepsis and septic shock in New York State showed a risk-adjusted association between more rapid antibiotic administration and bundled care completion, but not an intravenous fluid bolus, with reduced in-hospital mortality. However, it is unknown if clinically identifiable sepsis subtypes modify these associations. METHODS: Secondary analysis of patients with sepsis and septic shock enrolled in the New York State Department of Health cohort from January 1, 2015 to December 31, 2016. Patients were classified as clinical sepsis subtypes (α, ß, γ, δ-types) using the Sepsis ENdotyping in Emergency CAre (SENECA) approach. Exposure variables included time to 3-h sepsis bundle completion, antibiotic administration, and intravenous fluid bolus completion. Then logistic regression models evaluated the interaction between exposures, clinical sepsis subtypes, and in-hospital mortality. RESULTS: 55,169 hospitalizations from 155 hospitals were included (34% α, 30% ß, 19% γ, 17% δ). The α-subtype had the lowest (N = 1,905, 10%) and δ-subtype had the highest (N = 3,776, 41%) in-hospital mortality. Each hour to completion of the 3-h bundle (aOR, 1.04 [95%CI, 1.02-1.05]) and antibiotic initiation (aOR, 1.03 [95%CI, 1.02-1.04]) was associated with increased risk-adjusted in-hospital mortality. The association differed across subtypes (p-interactions < 0.05). For example, the outcome association for the time to completion of the 3-h bundle was greater in the δ-subtype (aOR, 1.07 [95%CI, 1.05-1.10]) compared to α-subtype (aOR, 1.02 [95%CI, 0.99-1.04]). Time to intravenous fluid bolus completion was not associated with risk-adjusted in-hospital mortality (aOR, 0.99 [95%CI, 0.97-1.01]) and did not differ among subtypes (p-interaction = 0.41). CONCLUSION: Timely completion of a 3-h sepsis bundle and antibiotic initiation was associated with reduced risk-adjusted in-hospital mortality, an association modified by clinically identifiable sepsis subtype.


Assuntos
Doenças Transmissíveis , Sepse , Choque Séptico , Humanos , Choque Séptico/tratamento farmacológico , Tempo para o Tratamento , Sepse/tratamento farmacológico , Antibacterianos/uso terapêutico
3.
Health Promot Int ; 35(6): 1312-1319, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31986195

RESUMO

Increasingly life is lived online, yet little is known about the actual nature and extent of online content that people view due to the difficulty of recording real time exposure. This includes people's exposure to harmful commodity marketing. This study aimed to develop a methodology to assess the nature and extent of exposure to, and engagement with, unhealthy commodity marketing and other public health harms online, particularly children's exposure. A convenience sample of 16 young adult participants (aged 21-29) recorded their device usage for 2 days using Zoom software. Data were coded and analysed to assess the nature and extent of marketing for alcohol, gambling, junk food and smoking products. Four focus groups were conducted with participants to explore their data collection and coding experiences, and results assessed using thematic analysis. The study found that, with some modifications, this method was feasible for gathering real-time objective data from the online world that can be analysed for a range of public health harms, including marketing of unhealthy commodities. Larger studies are recommended to build global evidence for public health action in the online world.


Assuntos
Jogo de Azar , Marketing , Criança , Grupos Focais , Humanos , Saúde Pública , Fumar , Adulto Jovem
4.
J Neurophysiol ; 121(5): 1879-1895, 2019 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-30811257

RESUMO

Recent work has quantified the geometric parameters of individual rat vibrissae (whiskers) and developed equations that describe how these parameters vary as a function of row and column position across the array. This characterization included a detailed quantification of whisker base diameter and arc length as well as the geometry of the whisker medulla. The present study now uses these equations for whisker geometry to quantify several properties of the whisker that govern its mechanical behavior. We first show that the average density of a whisker is lower in its proximal region than in its distal region. This density variation appears to be largely attributable to the presence of the whisker cuticle rather than the medulla. The density variation has very little effect on the center of mass of the whisker. We next show that the presence of the medulla decreases the deflection of the whisker under its own weight and also decreases its mass moment of inertia while sacrificing <1% stiffness at the whisker base compared with a solid whisker. Finally, we quantify two dimensionless parameters across the array. First, the deflection-to-length ratio decreases from caudal to rostral: caudal whiskers are longer but deflect more under their own weight. Second, the nondimensionalized radius of gyration is approximately constant across the array, which may simplify control of whisking by the intrinsic muscles. We anticipate that future work will exploit the mechanical properties computed in the present study to improve simulations of the mechanosensory signals associated with vibrissotactile exploratory behavior. NEW & NOTEWORTHY The mechanical signals transmitted by a whisker depend critically on its geometry. We used measurements of whisker geometry and mass to quantify the center of mass, mass moment of inertia, radius of gyration, and deflection under gravity of the whisker. We describe how variations in these quantities across the array could enhance sensing behaviors while reducing energy costs and simplifying whisking control. Most importantly, we provide derivations for these quantities for use in future simulation work.


Assuntos
Vibrissas/fisiologia , Animais , Variação Biológica da População , Fenômenos Biomecânicos , Feminino , Masculino , Movimento , Ratos , Ratos Sprague-Dawley , Vibrissas/anatomia & histologia
5.
J Neurophysiol ; 117(4): 1807-1820, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-27881718

RESUMO

Many rodents tactually sense the world through active motions of their vibrissae (whiskers), which are regularly arranged in rows and columns (arcs) on the face. The present study quantifies several geometric parameters of rat whiskers that determine the tactile information acquired. Findings include the following. 1) A meta-analysis of seven studies shows that whisker base diameter varies with arc length with a surprisingly strong dependence on the whisker's row position within the array. 2) The length of the whisker medulla varies linearly with whisker length, and the medulla's base diameter varies linearly with whisker base diameter. 3) Two parameters are required to characterize whisker "taper": radius ratio (base radius divided by tip radius) and radius slope (the difference between base and tip radius, divided by arc length). A meta-analysis of five studies shows that radius ratio exhibits large variability due to variations in tip radius, while radius slope varies systematically across the array. 4) Within the resolution of the present study, radius slope does not differ between the proximal and distal segments of the whisker, where "proximal" is defined by the presence of the medulla. 5) Radius slope of the medulla is offset by a constant value from radius slope of the proximal portion of the whisker. We conclude with equations for all geometric parameters as functions of row and column position.NEW & NOTEWORTHY Rats tactually explore their world by brushing and tapping their whiskers against objects. Each whisker's geometry will have a large influence on its mechanics and thus on the tactile signals the rat obtains. We performed a meta-analysis of seven studies to generate equations that describe systematic variations in whisker geometry across the rat's face. We also quantified the geometry of the whisker medulla. A database provides access to geometric parameters of over 500 rat whiskers.


Assuntos
Vias Aferentes/fisiologia , Tato/fisiologia , Vibrissas/inervação , Animais , Conjuntos de Dados como Assunto/estatística & dados numéricos , Feminino , Modelos Lineares , Estimulação Física , Ratos , Ratos Long-Evans
6.
Chem Res Toxicol ; 29(12): 2071-2095, 2016 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-27989132

RESUMO

Oxidative stress occurs when cellular reactive oxygen species levels exceed the self-antioxidant capacity of the body. Oxidative stress induces many pathological changes, including inflammation and cancer. Chronic inflammation is believed to be strongly associated with the major stages of carcinogenesis. The nuclear factor erythroid 2-related factor 2 (Nrf2) pathway plays a crucial role in regulating oxidative stress and inflammation by manipulating key antioxidant and detoxification enzyme genes via the antioxidant response element. Many dietary phytochemicals with cancer chemopreventive properties, such as polyphenols, isothiocyanates, and triterpenoids, exert antioxidant and anti-inflammatory functions by activating the Nrf2 pathway. Furthermore, epigenetic changes, including DNA methylation, histone post-translational modifications, and miRNA-mediated post-transcriptional alterations, also lead to various carcinogenesis processes by suppressing cancer repressor gene transcription. Using epigenetic research tools, including next-generation sequencing technologies, many dietary phytochemicals are shown to modify and reverse aberrant epigenetic/epigenome changes, potentially leading to cancer prevention/treatment. Thus, the beneficial effects of dietary phytochemicals on cancer development warrant further investigation to provide additional impetus for clinical translational studies.


Assuntos
Epigênese Genética , Inflamação , Neoplasias/prevenção & controle , Estresse Oxidativo , Compostos Fitoquímicos/administração & dosagem , Humanos
7.
Chem Res Toxicol ; 29(4): 694-703, 2016 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-26991801

RESUMO

It has previously been shown that curcumin can effectively inhibit prostate cancer proliferation and progression in TRAMP mice, potentially acting through the hypomethylation of the Nrf2 gene promoter and hence activation of the Nrf2 pathway to enhance cell antioxidative defense. FN1 is a synthetic curcumin analogue that shows stronger anticancer activity than curcumin in other reports. We aimed to explore the epigenetic modification of FN1 that restores Nrf2 expression in TRAMP-C1 cells. Stably transfected HepG2-C8 cells were used to investigate the effect of FN1 on the Nrf2- antioxidant response element (ARE) pathway. Real-time quantitative PCR and Western blotting were applied to study the influence of FN1 on endogenous Nrf2 and its downstream genes. Bisulfite genomic sequencing (BGS) and methylated DNA immunoprecipitation (MeDIP) were then performed to examine the methylation profile of the Nrf2 promoter. An anchorage-independent colony-formation analysis was conducted to examine the tumor inhibition activity of FN1. Epigenetic modification enzymes, including DNMTs and HDACs, were investigated by Western blotting. The luciferase reporter assay indicated that FN1 was more potent than curcumin in activating the Nrf2-ARE pathway. FN1 increased the expression of Nrf2 and its downstream detoxifying enzymes. FN1 significantly inhibited the colony formation of TRAMP-C1 cells. BGS and MeDIP assays revealed that FN1 treatment (250 nM for 3 days) reduced the percentage of CpG methylation of the Nrf2 promoter. FN1 also downregulated epigenetic modification enzymes. In conclusion, our results suggest that FN1 is a novel anticancer agent for prostate cancer. In the TRAMP-C1 cell line, FN1 can increase the level of Nrf2 and downstream genes via activating the Nrf2-ARE pathway and inhibit the colony formation potentially through the decreased expression of keap1 coupled with CpG demethylation of the Nrf2 promoter. This CpG demethylation effect may come from decreased epigenetic modification enzymes, such as DNMT1, DNMT3a, DNMT3b, and HDAC4.


Assuntos
Antineoplásicos/farmacologia , Curcumina/farmacologia , Epigênese Genética/efeitos dos fármacos , Fator 2 Relacionado a NF-E2/genética , Próstata/efeitos dos fármacos , Neoplasias da Próstata/tratamento farmacológico , Animais , Antineoplásicos/química , Linhagem Celular Tumoral , Ilhas de CpG/efeitos dos fármacos , Curcumina/análogos & derivados , Metilação de DNA/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Masculino , Camundongos , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia
8.
Chem Res Toxicol ; 25(8): 1574-80, 2012 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-22780686

RESUMO

Ginseng has long been used in Asian countries for more than 2000 years. Currently, in the "Western World or Western Medicines", many reports have indicated that they have used herbal medicines, and ginseng is one of the most popular herbs. Several recent reports have indicated that the antioxidant/antioxidative stress activities of ginseng play a role in the benefits of ginseng; however, the precise mechanism is lacking. The antioxidant response element (ARE) is a critical regulatory element for the expression of many antioxidant enzymes and phase II/III drug metabolizing/transporter genes, mediated by the transcription factor nuclear factor (erythroid-derived 2)-like 2 (Nrf2). The aim of this study was to examine the potential activation and synergism of Nrf2-ARE-mediated transcriptional activity between three common ginsenosides present in ginseng, ginsenoside Rb1 (Rb1), ginsenoside Rg1 (Rg1), and ginsenoside 20(S)-protopanaxatriol (20S). We tested whether these ginsenosides and their combinations could induce Nrf2-ARE activities in HepG2-C8 cells with stably transfected ARE luciferase reporter gene. Cell proliferation, antioxidant and ARE activities, Western blotting of Nrf2 protein, and qPCR of mRNA of Nrf2 were conducted for Rb1, Rg1, and 20S as well as the combinations of 20S with Rb1 or Rg1. To determine the combination effects, the combination index (CI) was calculated. Rb1 and Rg1 are relatively nontoxic to the cells, while 20S at 50 µM or above significantly inhibited the cell proliferation. Rb1, Rg1, or 20S induced total antioxidant activity and ARE activity in a concentration-dependent manner. Furthermore, combinations of 20S with either Rb1 or Rg1 induced total antioxidant and ARE activity synergistically. The induction of Nrf2 protein and mRNA was also found to be synergistic with the combination treatments. In summary, in this study, we show that ginsenosides Rb1, Rg1, and 20S possess antioxidant activity, transcriptionally activating ARE as well as the potential of synergistic activities. The Nrf2-ARE-mediated antioxidant pathway could play a role for the overall antioxidative stress activities, which could be important for ginseng's health beneficial effects such as cancer chemopreventive activities.


Assuntos
Antioxidantes/química , Ginsenosídeos/química , Fator 2 Relacionado a NF-E2/metabolismo , Sapogeninas/química , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Antioxidantes/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Ginsenosídeos/farmacologia , Células Hep G2 , Humanos , Camundongos , Fator 2 Relacionado a NF-E2/genética , Panax/química , Sapogeninas/farmacologia
9.
Contemp Clin Trials ; 119: 106822, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35697146

RESUMO

BACKGROUND: Monoclonal antibodies (mAb) that neutralize SARS-CoV-2 decrease hospitalization and death compared to placebo in patients with mild to moderate COVID-19; however, comparative effectiveness is unknown. We report the comparative effectiveness of bamlanivimab, bamlanivimab-etesevimab, and casirivimab-imdevimab. METHODS: A learning health system platform trial in a U.S. health system enrolled patients meeting mAb Emergency Use Authorization criteria. An electronic health record-embedded application linked local mAb inventory to patient encounters and provided random mAb allocation. Primary outcome was hospital-free days to day 28. Primary analysis was a Bayesian model adjusting for treatment location, age, sex, and time. Inferiority was defined as 99% posterior probability of an odds ratio < 1. Equivalence was defined as 95% posterior probability the odds ratio is within a given bound. FINDINGS: Between March 10 and June 25, 2021, 1935 patients received treatment. Median hospital-free days were 28 (IQR 28, 28) for each mAb. Mortality was 0.8% (1/128), 0.8% (7/885), and 0.7% (6/922) for bamlanivimab, bamlanivimab-etesevimab, and casirivimab-imdevimab, respectively. Relative to casirivimab-imdevimab (n = 922), median adjusted odds ratios were 0.58 (95% credible interval [CI] 0.30-1.16) and 0.94 (95% CI 0.72-1.24) for bamlanivimab (n = 128) and bamlanivimab-etesevimab (n = 885), respectively. These odds ratios yielded 91% and 94% probabilities of inferiority of bamlanivimab versus bamlanivimab-etesevimab and casirivimab-imdevimab, and an 86% probability of equivalence between bamlanivimab-etesevimab and casirivimab-imdevimab. INTERPRETATION: Among patients with mild to moderate COVID-19, bamlanivimab-etesevimab or casirivimab-imdevimab treatment resulted in 86% probability of equivalence. No treatment met prespecified criteria for statistical equivalence. Median hospital-free days to day 28 were 28 (IQR 28, 28) for each mAb. FUNDING AND REGISTRATION: This work received no external funding. The U.S. government provided the reported mAb. This trial is registered at ClinicalTrials.gov, NCT04790786.


Assuntos
COVID-19 , Sistema de Aprendizagem em Saúde , Anticorpos Monoclonais , Anticorpos Monoclonais Humanizados , Anticorpos Neutralizantes , Teorema de Bayes , Humanos , SARS-CoV-2
10.
JAMA Netw Open ; 5(7): e2220957, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35834252

RESUMO

Importance: The effectiveness of monoclonal antibodies (mAbs), casirivimab-imdevimab and sotrovimab, is unknown in patients with mild to moderate COVID-19 caused by the SARS-CoV-2 Delta variant. Objective: To evaluate the effectiveness of mAb against the Delta variant compared with no mAb treatment and to ascertain the comparative effectiveness of casirivimab-imdevimab and sotrovimab. Design, Setting, and Participants: This study comprised 2 parallel studies: (1) a propensity score-matched cohort study of mAb treatment vs no mAb treatment and (2) a randomized comparative effectiveness trial of casirivimab-imdevimab and sotrovimab. The cohort consisted of patients who received mAb treatment at the University of Pittsburgh Medical Center outpatient infusion centers and emergency departments from July 14 to September 29, 2021. Participants were patients with a positive SARS-CoV-2 test result who were eligible to receive mAbs according to emergency use authorization criteria. Exposure: For the trial, patients were randomized to either intravenous casirivimab-imdevimab or sotrovimab according to a system therapeutic interchange policy. Main Outcomes and Measures: For the cohort study, risk ratio (RR) estimates for the primary outcome of hospitalization or death by 28 days were compared between mAb treatment and no mAb treatment using propensity score-matched models. For the comparative effectiveness trial, the primary outcome was hospital-free days (days alive and free of hospitalization) within 28 days after mAb treatment, where patients who died were assigned -1 day in a bayesian cumulative logistic model adjusted for treatment location, age, sex, and time. Inferiority was defined as a 99% posterior probability of an odds ratio (OR) less than 1. Equivalence was defined as a 95% posterior probability that the OR was within a given bound. Results: A total of 3069 patients (1023 received mAb treatment: mean [SD] age, 53.2 [16.4] years; 569 women [56%]; 2046 had no mAb treatment: mean [SD] age, 52.8 [19.5] years; 1157 women [57%]) were included in the prospective cohort study, and 3558 patients (mean [SD] age, 54 [18] years; 1919 women [54%]) were included in the randomized comparative effectiveness trial. In propensity score-matched models, mAb treatment was associated with reduced risk of hospitalization or death (RR, 0.40; 95% CI, 0.28-0.57) compared with no treatment. Both casirivimab-imdevimab (RR, 0.31; 95% CI, 0.20-0.50) and sotrovimab (RR, 0.60; 95% CI, 0.37-1.00) were associated with reduced hospitalization or death compared with no mAb treatment. In the clinical trial, 2454 patients were randomized to receive casirivimab-imdevimab and 1104 patients were randomized to receive sotrovimab. The median (IQR) hospital-free days were 28 (28-28) for both mAb treatments, the 28-day mortality rate was less than 1% (n = 12) for casirivimab-imdevimab and less than 1% (n = 7) for sotrovimab, and the hospitalization rate by day 28 was 12% (n = 291) for casirivimab-imdevimab and 13% (n = 140) for sotrovimab. Compared with patients who received casirivimab-imdevimab, those who received sotrovimab had a median adjusted OR for hospital-free days of 0.88 (95% credible interval, 0.70-1.11). This OR yielded 86% probability of inferiority for sotrovimab vs casirivimab-imdevimab and 79% probability of equivalence. Conclusions and Relevance: In this propensity score-matched cohort study and randomized comparative effectiveness trial, the effectiveness of casirivimab-imdevimab and sotrovimab against the Delta variant was similar, although the prespecified criteria for statistical inferiority or equivalence were not met. Both mAb treatments were associated with a reduced risk of hospitalization or death in nonhospitalized patients with mild to moderate COVID-19 caused by the Delta variant. Trial Registration: ClinicalTrials.gov Identifier: NCT04790786.


Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Anticorpos Monoclonais Humanizados , Anticorpos Neutralizantes , Teorema de Bayes , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos
11.
Radiol Case Rep ; 16(6): 1348-1351, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33897927

RESUMO

Burns are one of the most common and devastating forms of trauma. Burns are a significant problem with high associated morbidity and mortality worldwide. Burn wound infection is a serious complication, which plays an important role in increasing the overall fatality rate in burn patients. In this study, we report a case of the polymicrobial burn wound infection involving V mimicus in a 56-year-old male, who was transferred from an outside hospital to the inpatient burn unit after sustaining traumatic and burn injuries in a firework explosion accident. The patient underwent surgical treatment and antibiotics with good improvement. Although rare, our case study will help to underscore the important role of V mimicus as a human pathogen.

12.
Clin Cancer Res ; 15(2): 597-606, 2009 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-19147765

RESUMO

PURPOSE: Immunoregulatory and suppressive mechanisms represent major obstacles to the success of immunotherapy in cancer patients. We have shown that the combination of radiotherapy to the primary tumor and CTL-associated protein 4 (CTLA-4) blockade induces antitumor immunity, inhibiting metastases and extending the survival of mice bearing the poorly immunogenic and highly metastatic 4T1 mammary carcinoma. Similarly to patients with metastatic cancer, however, mice were seldom cured. Here we tested the hypothesis that invariant natural killer T (iNKT) cells, a subset with unique regulatory functions, can regulate the response to radiotherapy and CTLA-4 blockade. EXPERIMENTAL DESIGN: The growth of 4T1 primary tumors and lung metastases was compared in wild-type and iNKT cell-deficient (iNKT-/-) mice. Treatment was started on day 13 when the primary tumors were palpable. Mice received radiotherapy to the primary tumor in two doses of 12 Gy in combination or not with 9H10 monoclonal antibody against CTLA-4. Response to treatment was assessed by measuring primary tumor growth delay/regression, survival, and number of lung metastases. RESULTS: The response to radiotherapy plus 9H10 was markedly enhanced in the absence of iNKT cells, with 50% of iNKT-/- versus 0% of wild-type mice showing complete tumor regression, long-term survival, and resistance to a challenge with 4T1 cells. Administration of the iNKT cell activator alpha-galactosylceramide did not enhance the response of wild-type mice to radiotherapy plus 9H10. Tumor-infiltrating iNKT cells were markedly reduced in wild-type mice treated with radiotherapy plus 9H10. CONCLUSIONS: iNKT cells play a major role in regulating the response to treatment with local radiotherapy and CTLA-4 blockade.


Assuntos
Antígenos CD/química , Células Matadoras Naturais/metabolismo , Neoplasias Mamárias Animais/tratamento farmacológico , Neoplasias Mamárias Animais/radioterapia , Linfócitos T/metabolismo , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/metabolismo , Antígeno CTLA-4 , Linhagem Celular Tumoral , Sobrevivência Celular , Imunossupressores/uso terapêutico , Neoplasias Pulmonares/patologia , Neoplasias Mamárias Animais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Metástase Neoplásica , Linfócitos T/citologia , Fatores de Tempo , Fator de Crescimento Transformador beta1/metabolismo
13.
IDCases ; 20: e00749, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32280588

RESUMO

Aggregatibacter actinomycetemcomitans (A. actinomycetemcomitans) is a facultative anaerobic Gram-negative coccobacillus that is associated with a variety of diseases in humans. In the present study, the isolate finally identified as A. actinomycetemcomitans by MALDI-TOF was misidentified as Pasturella canis or Pasturella multocida by the automated VITEK 2 system. The findings re-enforce the importance of an accurate and rapid diagnosis to assist patient management.

14.
Curr Biol ; 30(5): 815-826.e5, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-32004452

RESUMO

Compared to our understanding of the response properties of receptors in the auditory and visual systems, we have only a limited understanding of the mechanoreceptor responses that underlie tactile sensation. Here, we exploit the stereotyped morphology of the rat vibrissal (whisker) array to investigate coding and transduction properties of identified primary tactile afferents. We performed in vivo intra-axonal recording and labeling experiments to quantify response characteristics of four different types of identified mechanoreceptors in the vibrissal follicle: ring-sinus Merkel; lanceolate; clublike; and rete-ridge collar Merkel. Of these types, only ring-sinus Merkel endings exhibited slowly adapting properties. A weak inverse relationship between response magnitude and onset response latency was found across all types. All afferents exhibited strong "angular tuning," i.e., their response magnitude and latency depended on the whisker's deflection angle. Although previous studies suggested that this tuning should be aligned with the angular location of the mechanoreceptor in the follicle, such alignment was observed only for Merkel afferents; angular tuning of the other afferent types showed no clear alignment with mechanoreceptor location. Biomechanical modeling suggested that this tuning difference might be explained by mechanoreceptors' differential sensitivity to the force directed along the whisker length. Electron microscopic investigations of Merkel endings and lanceolate endings at the level of the ring sinus revealed unique anatomical features that may promote these differential sensitivities. The present study systematically integrates biomechanical principles with the anatomical and morphological characterization of primary afferent endings to describe the physical and cellular processing that shapes the neural representation of touch.


Assuntos
Axônios/fisiologia , Mecanorreceptores/fisiologia , Percepção do Tato/fisiologia , Vibrissas/fisiologia , Animais , Fenômenos Biomecânicos , Masculino , Modelos Biológicos , Ratos , Ratos Sprague-Dawley
15.
AAPS J ; 21(5): 83, 2019 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-31254216

RESUMO

Redox imbalance is a major contributor to the pathogenesis of melanoma and nonmelanoma skin cancer. Activation of the nuclear factor E2-related factor 2 (Nrf2) antioxidant responsive element (ARE) pathway is an intrinsic defense mechanism against oxidative stress. Flavonoids such as anthocyanidins, which are found abundantly in fruits and vegetables, have been shown to activate Nrf2. However, the epigenetic and genetic mechanisms by which anthocyanidins modulate the Nrf2-ARE pathway remain poorly understood in the context of skin cancer. In this study, delphinidin, one of the most potent and abundant anthocyanidins in berries, significantly inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced neoplastic cell transformation in mouse epidermal JB6 P+ cells by 69.4 to 99.4%. The mechanism was elucidated based on observations of increased ARE-driven luciferase activity and elevated mRNA and protein expression of Nrf2 downstream genes, such as heme oxygenase-1 (Ho-1), in JB6 P+ cells. Activation of the Nrf2-ARE pathway was correlated with demethylation of 15 CpG sites in the mouse Nrf2 promoter region between nt - 1226 and - 863 from the transcription start site. The reduced CpG methylation ratio in the Nrf2 promoter region was consistent with observed decreases in the protein expression of DNA methyltransferases 1 (DNMT1), DNMT3a, and class I/II histone deacetylases (HDACs). Overall, our results suggest that delphinidin, an epigenetic demethylating agent of the Nrf2 promoter, can activate the Nrf2-ARE pathway, which can be applied as a potential skin cancer chemopreventive agent.


Assuntos
Antocianinas/farmacologia , Células Epidérmicas/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Neoplasias Cutâneas/prevenção & controle , Animais , Antocianinas/administração & dosagem , Elementos de Resposta Antioxidante/genética , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Linhagem Celular , Células Epidérmicas/patologia , Epigênese Genética/efeitos dos fármacos , Heme Oxigenase-1/genética , Camundongos , Fator 2 Relacionado a NF-E2/metabolismo , Oxirredução/efeitos dos fármacos , Regiões Promotoras Genéticas , Neoplasias Cutâneas/genética , Acetato de Tetradecanoilforbol/toxicidade
16.
Am J Chin Med ; : 1-15, 2018 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-30284461

RESUMO

Qu-Yu-Jie-Du decoction (QYJD) is a commercially available traditional Chinese medicine (TCM). It is an aqueous extract of a Chinese herbal formula primarily consisting of eight TCM herbs: Taraxacum campylodes G.E. Haglund, Coix lacryma-jobi L., Smilax glabra Roxb., Sanguisorba officinalis L, Styphnolobium japonicum (L.) Schott, Prunus persica (L.) Batsch, Sophora flavescens Aiton, and Eupolyphaga sinensis Walker. Matrine and oxymatrine are two of the major phytochemical constituents of QYJD. Inflammation and oxidative stress are strongly associated with colon carcinogenesis. Colorectal cancer (CRC) is the third most common type of cancer. Therefore, cancer chemopreventive agents targeting CRC are urgently needed. This study was conducted to investigate the potential anticancer effects and the underlying mechanisms of QYJD and its active constituents, matrine and oxymatrine, in human colon cancer HT29 cells and in a dextran sulfate sodium (DSS)-induced colitis mouse model. QYJD and matrine effectively inhibited the proliferation and anchorage-independent growth of HT29 cells in a dose-dependent manner. QYJD and matrine also induced an Nrf2-mediated anti-oxidant response element-luciferase activity and upregulated the Nrf2-mediated anti-oxidative stress genes HO-1 and NQO1 at both the mRNA and protein levels. In the DSS-induced colitis mouse model, QYJD reduced the disease activity index (DAI) and alleviated colonic shortening. Elevated Nrf2 and HO-1 mRNA levels were also observed in QYJD-treated mice. These findings showed that QYJD could elicit anti-inflammatory and anti-oxidative stress response in vitro in a cell line and in vivo in a DSS-induced colitis mouse model. These responses may contribute to the overall anticolon cancer effect of QYJD.

17.
Cell Biosci ; 8: 3, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29344347

RESUMO

PURPOSE: We investigated the genomic DNA methylation profile of prostate cancer in transgenic adenocarcinoma of the mouse prostate (TRAMP) cancer model and to analyze the crosstalk among targeted genes and the related functional pathways. METHODS: Prostate DNA samples from 24-week-old TRAMP and C57BL/6 male mice were isolated. The DNA methylation profiles were analyzed by methylated DNA immunoprecipitation (MeDIP) followed by next-generation sequencing (MeDIP-seq). Canonical pathways, diseases and function and network analyses of the different samples were then performed using the Ingenuity® Pathway Analysis (IPA) software. Some target genes with significant difference in methylation were selected for validation using methylation specific primers (MSP) and qPCR. RESULTS: TRAMP mice undergo extensive aberrant CpG hyper- and hypo-methylation. There were 2147 genes with a significant (log2-change ≥ 2) change in CpG methylation between the two groups, as mapped by the IPA software. Among these genes, the methylation of 1105 and 1042 genes was significantly decreased and increased, respectively, in TRAMP prostate tumors. The top associated disease identified by IPA was adenocarcinoma; however, the cAMP response element-binding protein (CREB)-, histone deacetylase 2 (HDAC2)-, glutathione S-transferase pi (GSTP1)- and polyubiquitin-C (UBC)-related pathways showed significantly altered methylation profiles based on the canonical pathway and network analyses. MSP and qPCR results of genes of interests corroborated with MeDIP-seq findings. CONCLUSIONS: This is the first MeDIP-seq with IPA analysis of the TRAMP model to provide novel insight into the genome-wide methylation profile of prostate cancer. Studies on epigenetics, such as DNA methylation, will potentially provide novel avenues and strategies for further development of biomarkers targeted for treatment and prevention approaches for prostate cancer.

18.
Clin Cancer Res ; 11(2 Pt 1): 728-34, 2005 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-15701862

RESUMO

PURPOSE: Ionizing radiation therapy (RT) is an important component in the management of breast cancer. Although the primary tumor can be successfully treated by surgery and RT, metastatic breast cancer remains a therapeutic challenge. Here we tested the hypothesis that the combination of RT to the primary tumor with CTLA-4 blockade can elicit antitumor immunity inhibiting the metastases. EXPERIMENTAL DESIGN: The poorly immunogenic metastatic mouse mammary carcinoma 4T1 was used as a model. Mice were injected s.c. with 4T1 cells, and treatment was started 13 days later when the primary tumors measured 5 mm in average diameter. Mice were randomly assigned to four treatment groups receiving: (1) control IgG (IgG), (2) RT + IgG, (3) 9H10 monoclonal antibody against CTLA-4, (4) RT + 9H10. RT was delivered to the primary tumor by one or two fractions of 12 Gy. 9H10 and IgG were given i.p. thrice after RT. RESULTS: Consistent with the fact that 4T1 is poorly immunogenic, 9H10 alone did not have any effect on primary tumor growth or survival. RT was able to delay the growth of the primary irradiated tumor, but in the absence of 9H10 survival was similar to that of control mice. In contrast, mice treated with RT + 9H10 had a statistically significant survival advantage. The increased survival correlated with inhibition of lung metastases formation and required CD8+ but not CD4+ T cells. CONCLUSIONS: The combination of local RT with CTLA-4 blockade is a promising new immunotherapeutic strategy against poorly immunogenic metastatic cancers.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antígenos de Diferenciação/uso terapêutico , Neoplasias Mamárias Experimentais/imunologia , Neoplasias Mamárias Experimentais/terapia , Animais , Antígenos CD , Antígenos de Diferenciação/química , Antígenos de Diferenciação/imunologia , Antígeno CTLA-4 , Radioisótopos de Cobalto , Terapia Combinada , Modelos Animais de Doenças , Feminino , Fragmentos Fc das Imunoglobulinas/química , Fragmentos Fc das Imunoglobulinas/imunologia , Fragmentos Fc das Imunoglobulinas/uso terapêutico , Imunossupressores/química , Imunossupressores/imunologia , Imunossupressores/uso terapêutico , Neoplasias Pulmonares/imunologia , Neoplasias Pulmonares/secundário , Neoplasias Pulmonares/terapia , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Dosagem Radioterapêutica , Taxa de Sobrevida
19.
Front Behav Neurosci ; 10: 145, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27486390

RESUMO

During active tactile exploration with their whiskers (vibrissae), rodents can rapidly orient to an object even though there are very few proprioceptors in the whisker muscles. Thus a long-standing question in the study of the vibrissal system is how the rat can localize an object in head-centered coordinates without muscle-based proprioception. We used a three-dimensional model of whisker bending to simulate whisking motions against a peg to investigate the possibility that the 3D mechanics of contact from a single whisker are sufficient for localization in head-centered coordinates. Results show that for nearly all whiskers in the array, purely tactile signals at the whisker base - as would be measured by mechanoreceptors, in whisker-centered coordinates - could be used to determine the location of a vertical peg in head-centered coordinates. Both the "roll" and the "elevation" components of whisking kinematics contribute to the uniqueness and resolution of the localization. These results offer an explanation for a behavioral study showing that rats can more accurately determine the horizontal angle of an object if one column, rather than one row, of whiskers is spared.

20.
Curr Top Med Chem ; 16(7): 697-713, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26306989

RESUMO

Post-translational modifications can affect gene expression in a long-term manner without changes in the primary nucleotide sequence of the DNA. These epigenetic alterations involve dynamic processes that occur in histones, chromatin-associated proteins and DNA. In response to environmental stimuli, abnormal epigenetic alterations cause disorders in the cell cycle, apoptosis and other cellular processes and thus contribute to the incidence of diverse diseases, including cancers. In this review, we will summarize recent studies focusing on certain epigenetic readers, writers, and erasers associated with cancer development and how newly discovered natural compounds and their derivatives could interact with these targets. These advances provide insights into epigenetic alterations in cancers and the potential utility of these alterations as therapeutic targets for the future development of chemopreventive and chemotherapeutic drugs.


Assuntos
Produtos Biológicos/química , Epigênese Genética/efeitos dos fármacos , Animais , Metilação de DNA , Histonas/efeitos dos fármacos , Histonas/metabolismo , Humanos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos
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