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1.
J Clin Rheumatol ; 29(7): 332-340, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37644656

RESUMO

BACKGROUND: The type of failure may predict response to a second biologic. We evaluated the response to a second tumor necrosis factor inhibitor (TNFi) or non-TNFi in patients failing their initial TNFi, either primarily or secondarily. METHODS: Patients with rheumatoid arthritis who were biologic-naive and had a Clinical Disease Activity Index (CDAI) >10, who started their first TNFi for ≥3 months and then switched to a second biologic, were included in the study. Secondary failure was defined as 2 consecutive low-CDAI visits and then switching to a second biologic while they had moderate/severe CDAI. Primary failure was defined if it did not meet the definition of secondary failure, or if they had at least 1 moderate/severe CDAI after 3 months on treatment. We used multivariable logistic regression comparing primary versus secondary failure for achievement of CDAI ≤10 (primary outcome) and minimal clinically important differences (secondary outcome) at 6 months after switch. RESULTS: Of the 462 patients included, 64.3% and 35.7% stopped the first TNFi because of a primary and secondary failure, respectively. Patients with primary failure had a more severe disease (CDAI mean, 26.39 vs. 21.61; p < 0.001). The likelihood of achieving CDAI ≤10 (odds ratio, 4.367; 95% confidence interval, 2.428-7.856) and minimal clinically important difference (odds ratio, 2.851; 95% confidence interval, 1.619-5.020) was significantly higher for secondary than primary failure regardless of choice of a second agent. CONCLUSION: Patients with rheumatoid arthritis with secondary failure to a first TNFi responded better to a second biologic agent, regardless of the choice of biologic.


Assuntos
Antirreumáticos , Artrite Reumatoide , Produtos Biológicos , Humanos , Antirreumáticos/uso terapêutico , Fator de Necrose Tumoral alfa , Resultado do Tratamento , Artrite Reumatoide/tratamento farmacológico , Inibidores do Fator de Necrose Tumoral/uso terapêutico , Produtos Biológicos/uso terapêutico
2.
J Immunol ; 203(2): 441-452, 2019 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-31182479

RESUMO

Protease-activated receptor 2 (PAR-2) is expressed in various tissues, including lung, and when activated, promotes inflammation, differentiation, and migration of dendritic cells. We found that combining influenza virosomes containing hemagglutinin and neuraminidase with a PAR-2 agonist peptide (PAR-2AP) in an intranasal prime boost approach increased survival of mice challenged weeks later with lethal influenza virus over that by virosome or PAR-2AP prime boost alone. No weight loss occurred from influenza challenge after virosome-plus-PAR-2AP prime boost compared with either virosomes or PAR-2AP alone. Thus, virosomes plus PAR-2AP prevented morbidity as well as mortality. Through adoptive transfer, CD8+ lung T cells but not CD4+ T cells from virosomes plus PAR-2AP-primed mice protected from lethal influenza virus challenge and enhanced survival with less weight loss and faster recovery. Virosome-plus-PAR-2AP prime boost resulted in greater percentages of T effector memory phenotype cells (Tem) in lung, and higher frequencies of CD8 Tem and T central memory cells displayed effector functions in response to virus challenge in vivo. Virosome-plus-PAR-2AP prime boost also resulted in greater percentages of Ag-specific CD8+ T cells, both Tem and T central memory cells, in lungs of animals subsequently challenged with live influenza virus. Our findings indicate that PAR-2AP, a short peptide, may be a new and useful mucosal adjuvant.


Assuntos
Adjuvantes Imunológicos/farmacologia , Linfócitos T CD8-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/imunologia , Memória Imunológica/imunologia , Receptor PAR-2/agonistas , Virossomos/imunologia , Transferência Adotiva/métodos , Animais , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD4-Positivos/imunologia , Linhagem Celular , Cães , Feminino , Memória Imunológica/efeitos dos fármacos , Pulmão/imunologia , Pulmão/virologia , Células Madin Darby de Rim Canino , Camundongos , Camundongos Endogâmicos C57BL , Orthomyxoviridae/imunologia , Virossomos/efeitos dos fármacos
3.
Clin Infect Dis ; 71(9): e392-e398, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31955202

RESUMO

BACKGROUND: Diabetes was identified as a tuberculosis (TB) risk factor mostly in retrospective studies with limited assessments of metabolic variables. The prospective Effects of Diabetes on Tuberculosis Severity study compared adults with pulmonary TB in Chennai, India, who were classified as having either diabetes or a normal glucose tolerance at enrollment. METHODS: Baseline TB severity, sputum conversion, and treatment outcomes (cure, failure, death, or loss to follow-up) were compared between groups with respect to glycemic status and body mass index (BMI). RESULTS: The cohort of 389 participants included 256 with diabetes and 133 with a normal glucose tolerance. Low BMIs (<18.5 kg/m2) were present in 99 (74.4%) of nondiabetic participants and 85 (33.2%) of those with diabetes. Among participants with normal or high BMIs, rates of cure, treatment failure, or death did not vary by glycemic status. Participants with low BMIs had the highest radiographic severity of disease, the longest time to sputum culture conversion, and the highest rates of treatment failure and death. Among participants with low BMIs, poorly controlled diabetes (glycohemoglobin [HbA1c] ≥8.0%) was unexpectedly associated with better TB treatment outcomes. A high visceral adiposity index was associated with adverse outcomes and, despite an overall correlation with HbA1c, was elevated in some low-BMI individuals with normal glucose tolerance. CONCLUSIONS: In this South Indian cohort, a low BMI was significantly associated with an increased risk for adverse TB treatment outcomes, while comorbid, poorly controlled diabetes lessened that risk. A high visceral adiposity index, either with or without dysglycemia, might reflect a novel TB susceptibility mechanism linked to adipose tissue dysfunction.


Assuntos
Diabetes Mellitus , Tuberculose , Adulto , Índice de Massa Corporal , Diabetes Mellitus/epidemiologia , Humanos , Índia/epidemiologia , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia
5.
Photodermatol Photoimmunol Photomed ; 34(2): 112-116, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29080373

RESUMO

BACKGROUND/PURPOSE: Research suggests that youth proximity to tanning salons may promote use; however, little is known about tanning salon proximity to schools. We assessed the proximity of tanning salons to schools in urban versus rural/suburban communities across Worcester County, Massachusetts (population > 800K). To put findings in context, we compared school proximity to tanning salons to school proximity to McDonald's restaurants, a large franchise that also caters to young people. MATERIALS & METHODS: Accessibility was measured by ArcGIS 10.2 Network Analyzer (ESRI, Redlands, CA, USA) and the most current road network data layer from Massachusetts Department of Transportation (MassDOT). RESULTS: A total of 145 schools were observed in the study area, of which about 39% of schools were within 1 mile from a tanning salon. Urban schools (53.41%) had a higher proportion within 1 mile of a tanning salon than rural/suburban schools (17.54%; P < .001). More schools (39.31%) were within 1 mile of a tanning salon than schools within 1 mile of a McDonald's (22.70%; P < .001). CONCLUSIONS: Schools may be particularly impactful for implementing skin cancer prevention programing.


Assuntos
Indústria da Beleza , Neoplasias Cutâneas , População Suburbana , Banho de Sol , População Urbana , Adolescente , Adulto , Feminino , Humanos , Masculino , Massachusetts/epidemiologia , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/prevenção & controle
6.
Am J Dermatopathol ; 40(11): 836-840, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29794483

RESUMO

Cutaneous peripheral T-cell lymphoma, not otherwise specified represents a "waste basket" of all cases that cannot be put into another of the categories of mature cutaneous T-cell lymphoma. Previously, the sudden multifocal development of cutaneous CD4 tumors without preceding a patch or plaque stage was classified as d'emblée form of mycosis fungoides (MF). Currently, the term "MF" reserved only for the classic Alibert-Bazin type characterized by the evolution of patches, plaques, and tumors or for variants showing a similar clinical course. The authors describe a 75-year-old white woman who presented with a solitary skin tumor in the right supraclavicular region, with no lymph node or systemic involvement. Local external beam radiation treatment resulted in a complete response. The patient relapsed after 5 months with new tumors in the left neck and left upper chest. Biopsy of the lesions showed a dermal infiltrate of atypical small- to medium-sized T-lymphocytes, and immunohistochemical staining showed coexpression of CD4/CD8 in a subset of these cells, which was confirmed with flow cytometry of the tumor. Although the patient had no preceding patch or plaque stage, the authors herein report this extremely rare case of CD4/CD8 dual-positive peripheral T-cell lymphoma, not otherwise specified presented as MF d'emblée and discuss the seldom similar cases published previously.


Assuntos
Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/patologia , Linfoma Cutâneo de Células T/patologia , Micose Fungoide/patologia , Neoplasias Cutâneas/patologia , Idoso , Feminino , Humanos , Linfoma Cutâneo de Células T/imunologia , Micose Fungoide/imunologia , Neoplasias Cutâneas/imunologia
7.
Tob Control ; 26(2): 135-140, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27052096

RESUMO

OBJECTIVE: We evaluated retailer compliance with a cigar packaging and pricing regulation in Boston, Massachusetts, enacted in February 2012, and the regulation's impact on availability of single cigars. METHODS: Grape-flavoured Dutch Masters (DM) single-packaged cigars were examined as market indicator. At quarterly intervals from October 2011 to December 2014, availability and price of DM single cigars were observed through professional inspector visits to tobacco retailers in Boston (n=2232) and 10 comparison cities (n=3400). Differences in price and availability were examined between Boston and the comparison cities and across Boston neighbourhoods. RESULTS: The mean price of DM single cigars sold in Boston increased from under $1.50 in 2011 to above $2.50 in 2014, consistent with regulation requirements. Rates of retailer compliance reached 100% within 15 months postpolicy enactment based on observed price, and 97% at 30 months postenactment based on final sale prices. There was a 34.5% net decrease in the percentage of Boston retailers selling single cigars from 2011 to 2014. The number of Boston neighbourhoods with 3 or more retailers selling single cigars per 100 youth residents decreased from 12 in 2011 to 3 in 2014. No change in price or per cent of retailers selling single cigars was observed in the comparison cities in the same period. CONCLUSIONS: Retailers throughout Boston are in compliance with the regulation. The regulation has been effective in reducing levels and disparities in availability of flavoured single cigars popular with youth across Boston neighbourhoods, regardless of socioeconomic status and racial/ethnic composition.


Assuntos
Comércio/legislação & jurisprudência , Aromatizantes , Embalagem de Produtos/legislação & jurisprudência , Produtos do Tabaco/legislação & jurisprudência , Adolescente , Boston , Comércio/economia , Humanos , Produtos do Tabaco/economia
8.
Alzheimers Dement ; 13(12): 1389-1396, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28627379

RESUMO

INTRODUCTION: The mechanism triggering degeneration in Alzheimer's disease (AD) remains uncertain. Therapeutic failure following amyloid ß (Aß) removal casts doubt on amyloid neurotoxicity per se as the primary cause of AD. Impaired microvascular function has been suggested as an alternative etiology. People with Down syndrome (DS) develop Alzheimer's pathology, but whether microvascular impairment also occurs in DS (as in AD) is unknown. METHODS: We examined brain microvasculature in five DS subjects with AD-type histopathology, seven AD cases, and seven controls without AD-type pathology. We counted microvessels in five anatomic regions and assessed endothelial integrity by CD31 immunohistochemistry. RESULTS: Microvascular numbers and endothelial integrity were significantly diminished in DS brains compared with controls and were similar to AD brains. DISCUSSION: People with DS and trisomy 21 produce a large amount of Aß. If Alzheimer's pathology occurred in DS without microvascular loss or endothelial impairment, a direct neurotoxic Aß mechanism would be supported and microvascular impairment rejected. The observation of microvascular impairment in DS with Alzheimer's disease changes fails to reject the microvascular hypothesis and provides some support for this potential mechanism of injury.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Síndrome de Down/patologia , Microvasos/patologia , Adulto , Idoso , Doença de Alzheimer/complicações , Peptídeos beta-Amiloides/metabolismo , Síndrome de Down/complicações , Feminino , Humanos , Masculino , Microvasos/metabolismo , Pessoa de Meia-Idade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo
9.
Med Teach ; 38(4): 353-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26473666

RESUMO

BACKGROUND: Many medical schools have developed admission policies and clinical training programs designed to address the rural physician workforce shortages in their state. AIM: To enhance medical student rural clinical training experiences, and assist in preparing students for living and working in rural communities. METHODS: As part of their Rural Track Clerkship (RTC) Program, the University of Missouri School of Medicine developed the Community Integration Program (CIP). Students, individually or in groups, voluntarily identify a health need and implement a community-based project to meet that need. RESULTS: From 2007 to 2013, 80 (53%) students participated in the CIP and 86% completed the 11-item post-experience questionnaire. After the experience, participants reported a deeper understanding of the broad impact of a rural physician and the impact of rural culture on physician interactions. Participants reported they felt more integrated into the community, had a greater understanding of community health needs and resources, and were more likely to participate in future community service activities. CONCLUSIONS: The CIP exposes students to rural culture and helps them understand community health needs. Replication of this program can increase student interest in rural medicine and better prepare students for rural practice.


Assuntos
Estágio Clínico , Currículo , Serviços de Saúde Rural , Estudantes de Medicina , Educação Médica , Missouri
10.
Lancet ; 383(9931): 1814-23, 2014 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-24856027

RESUMO

BACKGROUND: The administration of intravenous fluid remains the cornerstone treatment for the prevention of contrast-induced acute kidney injury. However, no well-defined protocols exist to guide fluid administration in this treatment. We aimed to establish the efficacy of a new fluid protocol to prevent contrast-induced acute kidney injury. METHODS: In this randomised, parallel-group, comparator-controlled, single-blind phase 3 trial, we assessed the efficacy of a new fluid protocol based on the left ventricular end-diastolic pressure for the prevention of contrast-induced acute kidney injury in patients undergoing cardiac catheterisation. The primary outcome was the occurrence of contrast-induced acute kidney injury, which was defined as a greater than 25% or greater than 0·5 mg/dL increase in serum creatinine concentration. Between Oct 10, 2010, and July 17, 2012, 396 patients aged 18 years or older undergoing cardiac catheterisation with an estimated glomerular filtration rate of 60 mL/min per 1·73 m(2) or less and one or more of several risk factors (diabetes mellitus, history of congestive heart failure, hypertension, or age older than 75 years) were randomly allocated in a 1:1 ratio to left ventricular end-diastolic pressure-guided volume expansion (n=196) or the control group (n=200) who received a standard fluid administration protocol. Four computer-generated concealed randomisation schedules, each with permuted block sizes of 4, were used for randomisation, and participants were allocated to the next sequential randomisation number by sealed opaque envelopes. Patients and laboratory personnel were masked to treatment assignment, but the physicians who did the procedures were not masked. Both groups received intravenous 0·9% sodium chloride at 3 mL/kg for 1 h before cardiac catheterisation. Analyses were by intention to treat. Adverse events were assessed at 30 days and 6 months and all such events were classified by staff who were masked to treatment assignment. This trial is registered with ClinicalTrials.gov, number NCT01218828. FINDINGS: Contrast-induced acute kidney injury occurred less frequently in patients in the left ventricular end-diastolic pressure-guided group (6·7% [12/178]) than in the control group (16·3% [28/172]; relative risk 0·41, 95% CI 0·22-0·79; p=0·005). Hydration treatment was terminated prematurely because of shortness of breath in three patients in each group. INTERPRETATION: Left ventricular end-diastolic pressure-guided fluid administration seems to be safe and effective in preventing contrast-induced acute kidney injury in patients undergoing cardiac catheterisation. FUNDING: Kaiser Permanente Southern California regional research committee grant.


Assuntos
Injúria Renal Aguda/prevenção & controle , Meios de Contraste/efeitos adversos , Hidratação/métodos , Injúria Renal Aguda/induzido quimicamente , Injúria Renal Aguda/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Cateterismo Cardíaco/métodos , Protocolos Clínicos , Creatinina/sangue , Feminino , Hidratação/efeitos adversos , Hemodinâmica/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Terapia de Substituição Renal , Método Simples-Cego , Volume Sistólico/fisiologia
11.
Thorax ; 70(12): 1123-30, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26194996

RESUMO

RATIONALE: Hospitalised patients with acute exacerbation of COPD may deteriorate despite treatment, with early readmission being common. OBJECTIVES: To investigate whether neural respiratory drive, measured using second intercostal space parasternal muscle electromyography (EMGpara), would identify worsening dyspnoea and physician-defined inpatient clinical deterioration, and predict early readmission. METHODS: Patients admitted to a single-site university hospital with exacerbation of COPD were enrolled. Spirometry, inspiratory capacity (IC), EMGpara, routine physiological parameters, modified early warning score (MEWS), modified Borg scale for dyspnoea and physician-defined episodes of deterioration were recorded daily until discharge. Readmissions at 14 and 28 days post discharge were recorded. MEASUREMENTS AND MAIN RESULTS: 120 patients were recruited (age 70 ± 9 years, forced expiratory volume in 1 s (FEV1) of 30.5 ± 11.2%). Worsening dyspnoea, defined as at least one-point increase in Borg scale, was associated with increases in EMGpara%max and MEWS, whereas an increase in EMGpara%max alone was associated with physician-defined inpatient clinical deterioration. Admission-to-discharge change (Δ) in the normalised value of EMGpara (ΔEMGpara%max) was inversely correlated with ΔFEV1 (r = -0.38, p < 0.001) and ΔIC (r = -0.44, p < 0.001). ΔEMGpara%max predicted 14-day readmission (OR 1.13, 95% 1.03 to 1.23) in the whole cohort and 28-day readmission in patients under 85 years (OR 1.09, 95% CI 1.01 to 1.18). Age (OR 1.08, 95% CI 1.03 to 1.14) and 12-month admission frequency (OR 1.29, 1.01 to 1.66), also predicted 28-day readmission in the whole cohort. CONCLUSIONS: Measurement of neural respiratory drive by EMGpara represents a novel physiological biomarker that may be helpful in detecting inpatient clinical deterioration and identifying the risk of early readmission among patients with exacerbations of COPD. TRIAL REGISTRATION: NCT01361451.


Assuntos
Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Idoso , Progressão da Doença , Eletromiografia , Feminino , Volume Expiratório Forçado , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Curva ROC , Espirometria
12.
J Am Coll Nutr ; 34(2): 150-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25751264

RESUMO

OBJECTIVES: To analyze geographic and income disparities in access to healthy foods in central Massachusetts. METHODS: We surveyed 106 (92% of all) food stores longitudinally in the study area between 2007 and 2010. We analyzed the geographic and temporal variations in community- and store-level healthy food availability indices (HFAI) and unhealthy food availability indices (UFAI) overall and by select store and community characteristics. RESULTS: Twenty-seven of 68 communities in the study area (39.7%) had no food store and 5 (8.3%) had one or few stores with very limited availability of healthy foods, affecting 23.7% of the county population. Lack of food stores was associated strongly with lower housing density and upper tertile of median household income. About 45% of the surveyed stores had inadequate availabilities of healthy food. Store-level HFAI and UFAI scores were highly correlated, and higher among larger stores affiliated with a chain (vs independent). Though healthy foods were usually most available in larger stores, unhealthy foods were widely available in all stores. CONCLUSIONS: Over half of central Massachusetts communities, mostly rural and small, had either no food store or few stores with limited availabilities of healthy foods. Immediate policy interventions on the food environment are necessary in these communities. Further, without examining what is actually sold in stores, analysis of disparities in access to healthy food relies on the number of food stores, which can lead to a distorted picture of accessibility and mislead community health policies.


Assuntos
Comércio/estatística & dados numéricos , Abastecimento de Alimentos/estatística & dados numéricos , Comércio/normas , Alimentos , Geografia , Humanos , Renda , Estudos Longitudinais , Massachusetts , Política Nutricional , Características de Residência/estatística & dados numéricos , População Rural
13.
Tob Control ; 24(3): 256-62, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-24420311

RESUMO

BACKGROUND: Sales of smokeless tobacco products have increased in the USA. More than one in eight males in the 12th grade are current users of smokeless tobacco. Surveillance data examining nicotine levels of smokeless tobacco subsequent to 2006 have not been reported in the literature. METHODS: Data on nicotine levels and design features (eg, pH, moisture content, leaf cut and flavour) of smokeless tobacco products sold in Massachusetts were obtained from manufacturers between 2003 and 2012. Design features, levels and temporal trends in unionised (free) nicotine and nicotine content of smokeless tobacco products were analysed overall and by manufacturer and product type. RESULTS: The annual total number of moist snuff products increased from 99 in 2003 to 127 in 2012. The annual total number of reported snus products increased from 4 in 2003 to the highest level of 62 in 2011, before decreasing to 26 in 2012. Overall, mean unionised (free) nicotine remained relatively stable (ß=0.018 (95% CI -0.014 to 0.050) mg/g dry weight/year) from 2003 to 2012. However, both levels and temporal trends of mean free nicotine varied significantly among manufacturers (p<0.001). Since 2003, the free nicotine content of snus has increased at an overall rate of 0.192 (95% CI 0.138 to 0.246) mg/g dry weight/year, but varied by manufacturer (p<0.001). CONCLUSIONS: The number of smokeless tobacco products increased in the Massachusetts market. Further, mean unionised (free) nicotine levels in smokeless tobacco products of several manufacturers continued to rise despite decreasing levels from other manufacturers. The current success in tobacco control is very likely undermined without government surveillance, regulation and widespread public disclosure of nicotine levels in these products.


Assuntos
Comércio/estatística & dados numéricos , Nicotina/análise , Tabaco sem Fumaça , Concentração de Íons de Hidrogênio , Massachusetts , Paladar , Tabaco sem Fumaça/classificação , Tabaco sem Fumaça/economia , Tabaco sem Fumaça/estatística & dados numéricos , Tabaco sem Fumaça/provisão & distribuição , Água/análise
14.
Eur J Immunol ; 43(4): 929-38, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23436540

RESUMO

NK cells offer a first line of defense against viruses and are considered beneficial to the host during infection. Nevertheless, little is understood regarding the phenotype and function of NK cells in the lung during influenza virus infection. We found that the frequency of NK cells in mouse lung increased during influenza infection, with the majority of a mature phenotype. Cell surface CD107a and intracellular IFN-γ were detected in cells expressing multiple NK-cell receptors in infected lung, suggesting that NK cells were activated during infection. The activating receptor NKp46 was predominantly negative on such cells, possibly as a result of encountering influenza HA. Depletion of NK cells in vivo with anti-asialo GM1 or anti-NK1.1 reduced mortality from influenza infection and surviving mice recovered their body weight. Pathology induced by NK cells was only observed with high, not medium or low-dose influenza infection, indicating that the severity of infection influences NK-cell-mediated pathology. Furthermore, adoptive transfer of NK cells from influenza-infected lung, but not uninfected lung, resulted in more rapid weight loss and increased mortality of influenza-infected mice. Our results indicate that during severe influenza infection of the lung, NK cells have a deleterious impact on the host, promoting mortality.


Assuntos
Alphainfluenzavirus/imunologia , Células Matadoras Naturais/imunologia , Infecções por Orthomyxoviridae/imunologia , Transferência Adotiva , Animais , Feminino , Interferon gama/metabolismo , Células Matadoras Naturais/citologia , Células Matadoras Naturais/metabolismo , Ativação Linfocitária , Depleção Linfocítica , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Camundongos , Infecções por Orthomyxoviridae/mortalidade , Infecções por Orthomyxoviridae/virologia , Fenótipo , Pneumonia/imunologia , Pneumonia/virologia , Receptores KIR/metabolismo , Carga Viral , Redução de Peso
15.
Immunogenetics ; 66(7-8): 467-77, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24797174

RESUMO

The Ly49 receptor family plays an important role in the regulation of murine natural killer (NK) cell effector function. They recognize cell surface-expressed class I MHC (MHC-I) and are functionally equivalent to the killer Ig-related receptors (KIRs) in human NK cells. Ly49s exist in activating and inhibitory forms with highly homologous extracellular domains, displaying greater variability in the stalk regions. Inhibitory Ly49s can recognize self-MHC-I and therefore mediate tolerance to self. The role of activating Ly49 receptors is less clear. Some activating Ly49 receptors have been shown to recognize MHC-I molecules. The binding affinity of activating Ly49 receptors with MHC-I is currently unknown, and we sought to examine the affinities of two highly related receptors, an activating and an inhibitory Ly49 receptor, for their shared MHC-I ligands. The ectodomain of inhibitory Ly49G of the BALB/c mouse strain is highly similar to the Ly49W activating receptor in the nonobese diabetic (NOD) mouse. Recombinant soluble Ly49G and W were expressed, refolded, and analyzed for binding affinity with MHC-I by surface plasmon resonance. We found that Ly49G and Ly49W bound with similar affinity to the same MHC-I molecules. These results are a first determination of an activating Ly49 receptor affinity for MHC-I and show that, unlike prior results obtained with activating and inhibitory KIR receptors, functional homologues to Ly49 receptors, activating and inhibitory Ly49, can recognize common MHC-I ligands, with similar affinities.


Assuntos
Antígenos de Histocompatibilidade Classe I/metabolismo , Células Matadoras Naturais/imunologia , Subfamília A de Receptores Semelhantes a Lectina de Células NK/genética , Subfamília A de Receptores Semelhantes a Lectina de Células NK/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Antígenos HLA/genética , Antígenos HLA/metabolismo , Antígeno de Histocompatibilidade H-2D/genética , Antígeno de Histocompatibilidade H-2D/metabolismo , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Fenômenos Imunogenéticos , Ligantes , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Dados de Sequência Molecular , Subfamília A de Receptores Semelhantes a Lectina de Células NK/química , Ligação Proteica , Dobramento de Proteína , Estrutura Terciária de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Homologia de Sequência de Aminoácidos , Solubilidade , Especificidade da Espécie , Ressonância de Plasmônio de Superfície
16.
BMC Cancer ; 14: 862, 2014 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-25416148

RESUMO

BACKGROUND: Pancreatic cancer is one of the deadliest human malignancies, with few therapeutic options. Re-activation of embryonic signaling pathways is commonly in human pancreatic cancer and provided rationale to explore inhibition of these pathways therapeutically. Notch signaling is important during pancreatic development, and it is re-activated in pancreatic cancer. The functional role of Notch signaling during pancreatic carcinogenesis has been previously characterized using both genetic and drug-based approaches. However, contrasting findings were reported based on the study design. In fact, Notch signaling has been proposed to act as tumor-promoter or tumor-suppressor. Given the availability of Notch inhibitors in the clinic, understanding how this signaling pathway contributes to pancreatic carcinogenesis has important therapeutic implications. Here, we interrogated the role of Notch signaling specifically in the epithelial compartment of the pancreas, in the context of a genetically engineered mouse model of pancreatic cancer. METHODS: To inhibit Notch signaling in the pancreas epithelium, we crossed a mouse model of pancreatic cancer based on pancreas-specific expression of mutant Kras with a transgenic mouse that conditionally expresses a dominant negative form of the Mastermind-like 1 gene. MAML is an essential co-activator of the canonical Notch signaling-mediated transcription. DNMAML encodes a truncated MAML protein that represses all canonical Notch mediated transcription in a cell autonomous manner, independent of which Notch receptor is activated. As a result, in mice co-expressing mutant Kras and DNMAML, Notch signaling is inhibited specifically in the epithelium upon Cre-mediated recombination. We explored the effect of epithelial-specific DNMAML expression on Kras-driven carcinogenesis both during normal aging and following the induction of acute pancreatitis. RESULTS: We find that DNMAML expression efficiently inhibits epithelial Notch signaling and delays PanIN formation. However, over time, loss of Notch inhibition allows PanIN formation and progression. CONCLUSIONS: Epithelial-specific Notch signaling is important for PanIN initiation. Our findings indicate that PanIN formation can only occur upon loss of epithelial Notch inhibition, thus supporting an essential role of this signaling pathway during pancreatic carcinogenesis.


Assuntos
Neoplasias Pancreáticas/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais/fisiologia , Animais , Epitélio/química , Epitélio/metabolismo , Feminino , Masculino , Camundongos , Camundongos Transgênicos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Pâncreas/química , Pâncreas/metabolismo , Neoplasias Pancreáticas/genética , Pancreatite , Receptores Notch/genética , Transdução de Sinais/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
17.
Nicotine Tob Res ; 16(6): 753-8, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24420328

RESUMO

INTRODUCTION: Recent increases in nicotine yield of cigarettes sold in the United States have been attributed by tobacco manufacturers to natural variation in agricultural products. We tested this assertion using data reported by the manufacturers. METHODS: Data were collected from the annual reports filed with the Massachusetts Department of Public Health by 4 major manufacturers of cigarettes from 1997 to 2012. Reportable measures included nicotine yield (mg/cig) in smoke generated by a smoking machine based on the Massachusetts smoking regimen and nicotine content in the unburned tobacco per cigarette (mg/cig). We used multilevel linear mixed-effect models to examine temporal trends in and predictors of these measures, overall and by brand style and by brand family. RESULTS: While nicotine content remained relatively stable in the range of 12-14 mg/cig between 1998 and 2012, average nicotine yield increased significantly (p < .01) over time and ranged from the lowest level of 1.65 mg/cigarette in 1999 to the highest level of 1.89 mg/cigarette in 2011. Nicotine yield and yield-to-content ratio varied significantly among manufacturers and brand families. When controlling for market category and all available design features, the yield-to-content ratio of all manufacturers except Lorillard increased significantly over time. CONCLUSIONS: The data provided by tobacco manufacturers suggest that the increasing trend in yield is not related to variations in nicotine content but to the yield-to-content ratio, which contradicts their assertions of agricultural variations. Nicotine yield and yield-to-content ratio are controllable features of cigarettes, and they should be monitored and regulated by government agencies.


Assuntos
Nicotiana/química , Nicotina/análise , Fumaça/análise , Produtos do Tabaco/análise , Massachusetts , Indústria do Tabaco
18.
Semin Arthritis Rheum ; 68: 152504, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38991379

RESUMO

BACKGROUND: Cardiovascular disease (CVD) is the main cause of mortality in Rheumatoid Arthritis (RA). OBJECTIVE: To investigate the effect of biologic disease modifying anti-rheumatic drugs (bDMARDs) on lipids and CVD risk and evaluate associations with changes in systemic inflammation. METHODS: Patients with RA initiating a bDMARD were evaluated at baseline, 3 and 6 months later. Longitudinal mixed effects models examined the association of individual biologics with changes in lipid levelsm Reynolds Risk Score (RRS) and Framingham risk score. Mediation by CRP, clinical disease activity index (CDAI) or swollen joint count on lipid changes were modeled using structural equation models. The correlation between CRP changes and LDL changes was estimated. Changes of LDL-C at 6 months among patients with low baseline LDL-C (<90 mg/dl) vs higher baseline LDL-C(90-130, and >130 mg/dl) were compared. The association between LDL-C changes across baseline LDL-C groups and disease activity improvement was evaluated. RESULTS: 1698 bDMARD initiations were analyzed. Patients initiating tocilizumab had a significant increase in lipid levels but RRS at 3 and 6 months was similar across all biologics. Framingham risk score increased for patients treated with tocilizumab. Mediator analyses were statistically significant for the effects of CRP on lipid levels. Increases in LDL-C from baseline were independent of clinical response. An association of changes from baseline CRP and LDL-C were observed across all of the bDMARDs studied. CONCLUSION: Moderate increases in lipid levels on bDMARD treatment were not associated with an increased CVD risk by RRS regardless of the bDMARD initiated. Changes in CRP were significantly associated with changes in lipids in a mediator analysis.

19.
J Virol ; 86(4): 2229-38, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22130540

RESUMO

During the 2009 H1N1 influenza virus pandemic (pdmH1N1) outbreak, it was found that most individuals lacked antibodies against the new pdmH1N1 virus, and only the elderly showed anti-hemagglutinin (anti-HA) antibodies that were cross-reactive with the new strains. Different studies have demonstrated that prior contact with the virus can confer protection against strains with some degree of dissimilarity; however, this has not been sufficiently explored within the context of a pdmH1N1 virus infection. In this study, we have found that a first infection with the A/Brisbane/59/2007 virus strain confers heterologous protection in ferrets and mice against a subsequent pdmH1N1 (A/Mexico/4108/2009) virus infection through a cross-reactive but non-neutralizing antibody mechanism. Heterologous immunity is abrogated in B cell-deficient mice but maintained in CD8(-/-) and perforin-1(-/-) mice. We identified cross-reactive antibodies from A/Brisbane/59/2007 sera that recognize non-HA epitopes in pdmH1N1 virus. Passive serum transfer showed that cross-reactive sH1N1-induced antibodies conferred protection in naive recipient mice during pdmH1N1 virus challenge. The presence or absence of anti-HA antibodies, therefore, is not the sole indicator of the effectiveness of protective cross-reactive antibody immunity. Measurement of additional antibody repertoires targeting the non-HA antigens of influenza virus should be taken into consideration in assessing protection and immunization strategies. We propose that preexisting cross-protective non-HA antibody immunity may have had an overall protective effect during the 2009 pdmH1N1 outbreak, thereby reducing disease severity in human infections.


Assuntos
Anticorpos Antivirais/imunologia , Linfócitos B/imunologia , Antígenos CD8/imunologia , Proteção Cruzada , Vírus da Influenza A Subtipo H1N1/imunologia , Influenza Humana/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Embrião de Galinha , Feminino , Furões , Humanos , Vírus da Influenza A Subtipo H1N1/fisiologia , Influenza Humana/epidemiologia , Influenza Humana/virologia , Masculino , México/epidemiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pandemias
20.
J Immunol ; 187(6): 3267-76, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21841133

RESUMO

Members of the rodent Ly49 receptor family control NK cell responsiveness and demonstrate allele specificity for MHC class I (MHC-I) ligands. For example, the rat Ly49i2 inhibitory NK cell receptor binds RT1-A1(c) but not other rat MHC class Ia or Ib molecules. RT1-A1(c) preferentially binds peptides with proline at the second, or P2, position, which defines it as an HLA-B7 supertype MHC-I molecule. Previously, our laboratory showed that mutations within the MHC-I supertype-defining B-pocket of RT1-A1(c) could lead to alterations in P2 anchor residues of the peptide repertoire bound by RT1-A1(c) and loss of recognition by Ly49i2. Although suggestive of peptide involvement, it was unclear whether the peptide P2 anchor residue or alteration of the RT1-A1(c) primary sequence influenced Ly49i2 recognition. Therefore, we directly investigated the role of the P2 anchor residue of RT1-A1(c)-bound peptides in Ly49i2 recognition. First, fluorescent multimers generated by refolding soluble recombinant RT1-A1(c) with individual synthetic peptides differing only at the P2 anchor residue were examined for binding to Ly49i2 NK cell transfectants. Second, cytotoxicity by Ly49i2-expressing NK cells toward RMA-S target cells expressing RT1-A1(c) bound with peptides that only differ at the P2 anchor residue was evaluated. Our results demonstrate that Ly49i2 recognizes RT1-A1(c) bound with peptides that have Pro or Val at P2, whereas little or no recognition is observed when RT1-A1(c) is complexed with peptide bearing Gln at P2. Thus, the identity of the P2 peptide anchor residue is an integral component of MHC-I recognition by Ly49i2.


Assuntos
Antígenos Ly/química , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade/imunologia , Células Matadoras Naturais/imunologia , Receptores Imunológicos/química , Sequência de Aminoácidos , Animais , Antígenos Ly/metabolismo , Separação Celular , Citotoxicidade Imunológica/imunologia , Eletroforese em Gel de Poliacrilamida , Citometria de Fluxo , Antígenos de Histocompatibilidade Classe I/metabolismo , Células Matadoras Naturais/metabolismo , Ativação Linfocitária/imunologia , Dados de Sequência Molecular , Ligação Proteica/imunologia , Conformação Proteica , Ratos , Receptores Imunológicos/metabolismo
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