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1.
Domest Anim Endocrinol ; 71: 106389, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31731251

RESUMO

Thyroid disease is common in cats, but little is known about the biologic variability of serum thyroid hormone concentrations and its impact on diagnostic utility in either healthy cats or cats with thyroid disease. The purpose of this study was to determine the biological variation, index of individuality, and reference change values for thyroid hormones and thyroid-stimulating hormone (TSH) in clinically healthy cats. Serum samples for analysis of total thyroxine (T4), triiodothyronine (T3), free T4 by dialysis, and TSH were obtained weekly for 6 wk from 10 healthy cats, then frozen until single-batch analyzed. Data were evaluated for outliers, and we determined the CV within individual cats (CVI) and between individual cats (CVG) for each hormone and the variation between duplicates or analytical variation (CVA). The index of individuality and reference change values for each hormone were then calculated. Serum concentrations of total T4, free T4, T3, and TSH all showed greater variation between cats (CVG) than within cats (CVI). Total and free T4 had an intermediate index of individuality (1.1 and 1.2, respectively), suggesting that these hormones would be best evaluated by a combination of their population-based reference intervals and reference change values. Serum TSH concentrations had high index of individuality (1.8), suggesting this hormone would be best evaluated with reference change values rather than the population-based reference interval. Total T3 also had a high calculated index of individuality (1.8); however, T3 had high ratio of analytical variation (CVA) to within cat variation (CVI), so RCV could not be accurately calculated. This study demonstrates that clinically normal cats show considerable interindividual biological variation in serum thyroid hormone and TSH concentrations, whereas the intraindividual variability in hormone concentrations is much narrower. This suggests that for all serum thyroid hormones, but especially serum TSH and T3 concentrations, comparing individual cat's hormone results to a population-based reference interval may be misleading, especially in those with early or subclinical thyroid disease. Clinicians might improve the diagnosis of feline thyroid disease by establishing baseline concentrations of T4, free T4, T3, and TSH for individual cats (ideally when healthy) and applying reference change values to subsequent measurements.


Assuntos
Gatos/sangue , Hormônios Tireóideos/sangue , Tireotropina/sangue , Tiroxina/sangue , Tri-Iodotironina/sangue , Animais , Feminino , Masculino , Valores de Referência , Fatores de Tempo
2.
J Small Anim Pract ; 59(7): 411-414, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29602218

RESUMO

OBJECTIVE: To describe the treatment of sinonasal aspergillosis with topical 1% clotrimazole solution in dogs with cribriform plate lysis. MATERIALS AND METHODS: This retrospective study includes data retrieval from medical records of dogs with sinonasal aspergillosis and cribriform plate lysis that underwent topical treatment with 1% clotrimazole solution. RESULTS: Five dogs with sinonasal aspergillosis, cribriform plate lysis diagnosed on CT scans, and normal neurologic examinations were treated with a single (n=3) or multiple (n=2) infusions of clotrimazole solution. No dogs developed clinical neurologic disease after therapy. CLINICAL SIGNIFICANCE: In this study, a topical clotrimazole solution was not associated with adverse neurologic effects in neurologically normal dogs with sinonasal aspergillosis and cribriform plate lysis.


Assuntos
Antifúngicos/uso terapêutico , Aspergilose/veterinária , Clotrimazol/uso terapêutico , Doenças do Cão/tratamento farmacológico , Doenças Nasais/veterinária , Administração Tópica , Animais , Antifúngicos/administração & dosagem , Aspergilose/tratamento farmacológico , Clotrimazol/administração & dosagem , Doenças do Cão/microbiologia , Cães , Osso Etmoide/patologia , Feminino , Masculino , Doenças Nasais/tratamento farmacológico , Doenças Nasais/microbiologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/veterinária , Resultado do Tratamento
3.
Mucosal Immunol ; 11(3): 861-870, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29363669

RESUMO

Ulcerative colitis (UC) patients exhibit elevated histamine, but how histamine exacerbates disease is unclear as targeting histamine 1 receptor (H1R) or H2R is clinically ineffective. We hypothesized that histamine functioned instead through the other colon-expressed histamine receptor, H4R. In humans, UC patient biopsies exhibited increased H4R RNA and protein expression over control tissue, and immunohistochemistry showed that H4R was in proximity to immunopathogenic myeloperoxidase-positive neutrophils. To characterize this association further, we employed both the oxazolone (Ox)- and dextran sulfate sodium (DSS)-induced experimental colitis mouse models and also found upregulated H4R expression. Mast cell (MC)-derived histamine and H4R drove experimental colitis, as H4R-/- mice had lower symptom scores, neutrophil-recruitment mediators (colonic interleukin-6 (IL-6), CXCL1, CXCL2), and mucosal neutrophil infiltration than wild-type (WT) mice, as did MC-deficient KitW-sh/W-sh mice reconstituted with histidine decarboxylase-deficient (HDC-/-) bone marrow-derived MCs compared with WT-reconstituted mice; adaptive responses remained intact. Furthermore, Rag2-/- × H4R-/- mice had reduced survival, exacerbated colitis, and increased bacterial translocation than Rag2-/- mice, revealing an innate protective antibacterial role for H4R. Taken together, colonic MC-derived histamine initiates granulocyte infiltration into the colonic mucosa through H4R, suggesting alternative therapeutic targets beyond adaptive immunity for UC.


Assuntos
Colite Ulcerativa/imunologia , Colite/imunologia , Colo/imunologia , Histamina/metabolismo , Mucosa Intestinal/imunologia , Mastócitos/fisiologia , Receptores Histamínicos H4/metabolismo , Adolescente , Adulto , Idoso , Animais , Células Cultivadas , Colite/induzido quimicamente , Sulfato de Dextrana , Modelos Animais de Doenças , Feminino , Histidina Descarboxilase/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Infiltração de Neutrófilos , Oxazolona , Receptores Histamínicos H4/genética , Adulto Jovem
4.
Mol Psychiatry ; 23(5): 1328-1335, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-28439100

RESUMO

Impulsivity, a multifaceted behavioral hallmark of attention-deficit/hyperactivity disorder (ADHD), strongly influences addiction vulnerability and other psychiatric disorders that incur enormous medical and societal burdens yet the neurobiological underpinnings linking impulsivity to disease remain poorly understood. Here we report the critical role of ventral striatal cAMP-response element modulator (CREM) in mediating impulsivity relevant to drug abuse vulnerability. Using an ADHD rat model, we demonstrate that impulsive animals are neurochemically and behaviorally more sensitive to heroin and exhibit reduced Crem expression in the nucleus accumbens core. Virally increasing Crem levels decreased impulsive action, thus establishing a causal relationship. Genetic studies in seven independent human populations illustrate that a CREM promoter variant at rs12765063 is associated with impulsivity, hyperactivity and addiction-related phenotypes. We also reveal a role of Crem in regulating striatal structural plasticity. Together, these results highlight that ventral striatal CREM mediates impulsivity related to substance abuse and suggest that CREM and its regulated network may be promising therapeutic targets.


Assuntos
Transtornos de Deficit da Atenção e do Comportamento Disruptivo/metabolismo , Comportamento Aditivo/metabolismo , Modulador de Elemento de Resposta do AMP Cíclico/metabolismo , Transtornos Relacionados ao Uso de Substâncias/metabolismo , Estriado Ventral/metabolismo , Adulto , Animais , Transtornos de Deficit da Atenção e do Comportamento Disruptivo/psicologia , Comportamento Aditivo/psicologia , Encéfalo/metabolismo , Modelos Animais de Doenças , Humanos , Comportamento Impulsivo/fisiologia , Masculino , Núcleo Accumbens/metabolismo , Ratos , Ratos Endogâmicos SHR , Ratos Endogâmicos WKY , Transtornos Relacionados ao Uso de Substâncias/psicologia
5.
J Vet Intern Med ; 31(3): 723-729, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28382700

RESUMO

BACKGROUND: Thyroid cysts are rare in cats and poorly documented. OBJECTIVES: To report distinguishing clinical features and treatment responses of cats with thyroid cysts. ANIMALS: Forty client-owned cats. METHODS: Retrospective review of medical records for cats with thyroid cysts confirmed by scintigraphy, ultrasound, magnetic resonance imaging, or necropsy at 4 referral centers between 2005 and 2016. Signalment, clinical findings, diagnostic testing, treatment, and outcome were recorded. RESULTS: Cats ranged in age from 8 to 20 years with no apparent breed or sex predilection. 37 of 40 (93%) cats were hyperthyroid (duration, 1-96 months). Clinical findings included palpable neck mass (40/40, 100%), weight loss (15/40, 38%), dysphagia (8/40, 20%), decreased appetite (5/40, 13%), and dyspnea (4/40, 10%). Cysts were classified as small (≤8 cm3 ) in 16 (40%) and large (>8 cm3 ) in 24 (60%) cats. Of 25 cats treated with radioiodine, hyperthyroidism resolved in 23 (92%), whereas thyroid cysts resolved in 12 (50%). Radioiodine treatment resolved small cysts in 8 of 13 (62%) cats and large cysts in 4 of 11 (36%) cats. Eight cats, including 2 euthyroid cats, underwent thyroid-cystectomy; 3 with bilateral thyroid involvement were euthanized postoperatively for hypocalcemia. Excised cystic thyroid masses were identified as cystadenoma (4) and carcinoma (4). CONCLUSIONS AND CLINICAL IMPORTANCE: Thyroid cysts are encountered in hyperthyroid and euthyroid cats with benign and malignant thyroid tumors. Radioiodine treatment alone inconsistently resolved thyroid cysts. Thyroid-cystectomy could be considered in cats with unilateral thyroid disease or when symptomatic cysts persist despite successful radioiodine treatment of hyperthyroidism.


Assuntos
Doenças do Gato/epidemiologia , Neoplasias da Glândula Tireoide/veterinária , Animais , Carcinoma/epidemiologia , Carcinoma/veterinária , Doenças do Gato/sangue , Doenças do Gato/diagnóstico por imagem , Doenças do Gato/patologia , Gatos , Cistadenoma/epidemiologia , Cistadenoma/veterinária , Cistos/epidemiologia , Cistos/veterinária , Feminino , Radioisótopos do Iodo , Imageamento por Ressonância Magnética/veterinária , Masculino , New York/epidemiologia , Cintilografia/veterinária , Estudos Retrospectivos , Neoplasias da Glândula Tireoide/epidemiologia , Tiroxina/sangue , Tiroxina/metabolismo , Tomografia Computadorizada por Raios X/veterinária
6.
Am J Transplant ; 17(1): 81-90, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27273890

RESUMO

Recent clinical studies suggest that operational allograft tolerance can be persistent, but long-term surviving allografts can be rejected in a subset of patients, sometimes after episodes of infection. In this study, we examined the impact of Listeria monocytogenes (Lm) infection on the quality of tolerance in a mouse model of heart allograft transplantation. Lm infection induced full rejection in 40% of tolerant recipients, with the remaining experiencing a rejection crisis or no palpable change in their allografts. In the surviving allografts on day 8 postinfection, graft-infiltrating cell numbers increased and exhibited a loss in the tolerance gene signature. By day 30 postinfection, the tolerance signature was broadly restored, but with a discernible reduction in the expression of a subset of 234 genes that marked tolerance and was down-regulated at day 8 post-Lm infection. We further demonstrated that the tolerant state after Lm infection was functionally eroded, as rejection of the long-term surviving graft was induced with anti-PD-L1 whereas the same treatment had no effect in noninfected tolerant mice. Collectively, these observations demonstrate that tolerance, even if initially robust, exists as a continuum that can be eroded following bystander immune responses that accompany certain infections.


Assuntos
Rejeição de Enxerto/imunologia , Sobrevivência de Enxerto/imunologia , Transplante de Coração/efeitos adversos , Listeria monocytogenes/imunologia , Listeriose/imunologia , Tolerância ao Transplante/imunologia , Animais , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/virologia , Listeriose/virologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transplante Homólogo
7.
J Pediatr Surg ; 52(1): 149-152, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27865473

RESUMO

BACKGROUND/PURPOSE: Although prohibitively labor intensive, manual data extraction (MDE) is the prevailing method used to obtain clinical research and quality improvement (QI) data. Automated data extraction (ADE) offers a powerful alternative. The purposes of this study were to 1) assess the feasibility of ADE from provider-authored outpatient documentation, and 2) evaluate the effectiveness of ADE compared to MDE. METHODS: A prospective collection of data was performed on 90 ADE-templated notes (N=71 patients) evaluated in our bowel management clinic. ADE captured data were compared to 59 MDE notes (N=51) collected under an IRB-exempt review. Sixteen variables were directly comparable between ADE and MDE. RESULTS: MDE for 59 clinic notes (27 unique variables) took 6months to complete. ADE-templated notes for 90 clinic notes (154 unique variables) took 5min to run a research/QI report. Implementation of ADE included eight weeks of development and testing. Pre-implementation clinical documentation was similar to post-implementation documentation (5-10min). CONCLUSIONS: ADE-templated notes allow for a 5-fold increase in clinically relevant data that can be captured with each encounter. ADE also results in real-time data extraction to a research/QI database that is easily queried. The immediate availability of these data, in a research-formatted spreadsheet, allows for rapid collection, analyses, and interpretation of the data. LEVEL OF EVIDENCE: IV. TYPE OF STUDY: Retrospective Study.


Assuntos
Documentação/normas , Processamento Eletrônico de Dados/normas , Melhoria de Qualidade , Idoso , Pesquisa Biomédica , Registros Eletrônicos de Saúde , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos
8.
Am J Transplant ; 16(10): 2842-2853, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27063351

RESUMO

T cell receptor transgenic (TCR-Tg) T cells are often used as tracer populations of antigen-specific responses to extrapolate findings to endogenous T cells. The extent to which TCR-Tg T cells behave purely as tracer cells or modify the endogenous immune response is not clear. To test the impact of TCR-Tg T cell transfer on endogenous alloimmunity, recipient mice were seeded with CD4+ or CD8+ TCR-Tg or polyclonal T cells at the time of cardiac allograft transplantation. Only CD4+ TCR-Tg T cells accelerated rejection and, unexpectedly, led to a dose-dependent decrease in both transferred and endogenous T cells infiltrating the graft. In contrast, recipients of CD4+ TCR-Tg T cells exhibited enhanced endogenous donor-specific CD8+ T cell activation in the spleen and accelerated alloantibody production. Introduction of CD4+ TCR-Tg T cells also perturbed the intragraft accumulation of innate cell populations. Transferred CD4+ TCR-Tg T cells alter many aspects of endogenous alloimmunity, suggesting that caution should be used when interpreting experiments using these adoptively transferred cells because the overall nature of allograft rejection may be altered. These results also may have implications for adoptive CD4+ T cell immunotherapy in tumor and infectious clinical settings because cell infusion may have additional effects on natural immune responses.


Assuntos
Células Apresentadoras de Antígenos/imunologia , Linfócitos T CD4-Positivos/imunologia , Rejeição de Enxerto/imunologia , Transplante de Coração , Isoanticorpos/imunologia , Receptores de Antígenos de Linfócitos T/imunologia , Subpopulações de Linfócitos T/imunologia , Transferência Adotiva , Aloenxertos , Animais , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T/metabolismo
9.
Am J Transplant ; 16(10): 2854-2864, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27091509

RESUMO

Solid organ transplantation tolerance can be achieved following select transient immunosuppressive regimens that result in long-lasting restraint of alloimmunity without affecting responses to other antigens. Transplantation tolerance has been observed in animal models following costimulation or coreceptor blockade therapies, and in a subset of patients through induction protocols that include donor bone marrow transplantation, or following withdrawal of immunosuppression. Previous data from our lab and others have shown that proinflammatory interventions that successfully prevent the induction of transplantation tolerance in mice often fail to break tolerance once it has been stably established. This suggests that established tolerance acquires resilience to proinflammatory insults, and prompted us to investigate the mechanisms that maintain a stable state of robust tolerance. Our results demonstrate that only a triple intervention of depleting CD25+ regulatory T cells (Tregs), blocking programmed death ligand-1 (PD-L1) signals, and transferring low numbers of alloreactive T cells was sufficient to break established tolerance. We infer from these observations that Tregs and PD-1/PD-L1 signals cooperate to preserve a low alloreactive T cell frequency to maintain tolerance. Thus, therapeutic protocols designed to induce multiple parallel mechanisms of peripheral tolerance may be necessary to achieve robust transplantation tolerance capable of maintaining one allograft for life in the clinic.


Assuntos
Rejeição de Enxerto/imunologia , Transplante de Coração , Receptores de Antígenos de Linfócitos T/imunologia , Subpopulações de Linfócitos T/imunologia , Linfócitos T Reguladores/imunologia , Tolerância ao Transplante/imunologia , Transferência Adotiva , Aloenxertos , Animais , Antígeno B7-H1/imunologia , Antígeno B7-H1/metabolismo , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Receptores de Antígenos de Linfócitos T/metabolismo
10.
Am J Transplant ; 16(8): 2312-23, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-26928966

RESUMO

Antibody-mediated rejection has emerged as the leading cause of late graft loss in kidney transplant recipients, and inhibition of donor-specific antibody production should lead to improved transplant outcomes. The fusion protein cytotoxic T lymphocyte-associated protein 4-immunoglobulin (CTLA4-Ig) blocks T cell activation and consequently inhibits T-dependent B cell antibody production, and the current paradigm is that CTLA4-Ig is effective with naïve T cells and less so with activated or memory T cells. In this study, we used a mouse model of allosensitization to investigate the efficacy of continuous CTLA4-Ig treatment, initiated 7 or 14 days after sensitization, for inhibiting ongoing allospecific B cell responses. Delayed treatment with CTLA4-Ig collapsed the allospecific germinal center B cell response and inhibited alloantibody production. Using adoptively transferred T cell receptor transgenic T cells and a novel approach to track endogenous graft-specific T cells, we demonstrate that delayed CTLA4-Ig minimally inhibited graft-specific CD4(+) and T follicular helper responses. Remarkably, delaying CTLA4-Ig until day 6 after transplantation in a fully mismatched heart transplant model inhibited alloantibody production and prevented acute rejection, whereas transferred hyperimmune sera reversed the effects of delayed CTLA4-Ig. Collectively, our studies revealed the unexpected efficacy of CTLA4-Ig for inhibiting ongoing B cell responses even when the graft-specific T cell response was robustly established.


Assuntos
Linfócitos B/imunologia , Antígeno CTLA-4/imunologia , Rejeição de Enxerto/prevenção & controle , Transplante de Coração/efeitos adversos , Imunoconjugados/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Feminino , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto/imunologia , Isoanticorpos/imunologia , Ativação Linfocitária , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Transplante Homólogo
11.
J Fish Biol ; 88(4): 1335-49, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26887788

RESUMO

Life-history characteristics of age-0 sturgeon chub Macrhybopsis gelida, shoal chub Macrhybopsis hyostoma and sicklefin chub Macrhybopsis meeki were compared using several methods. All Macrhybopsis species consumed mostly midge pupae, but M. meeki had the most general diet (Levins' index, B = 0.22) compared with M. hyostoma (B = 0.02) and M. gelida (B = 0.09). Morisita's diet overlap index among species pairs ranged from 0.62 to 0.97 and was highest between M. hyostoma and M. gelida. Daily ages estimated from lapilli otoliths for each species ranged from 15 to 43 days for M. gelida, 19 to 44 for M. hyostoma and from 16 to 64 days for M. meeki. Mean growth rates ranged from 0.79 mm day(-1) for M. meeki to 1.39 mm day(-1) for M. gelida. Mortality estimates indicated high daily survivorship rates for M. meeki (0.985), but could not be estimated for the other two species. Hatch date histograms were congruent with the belief that M. hyostoma and M. gelida spawn periodically from June to September. Macrhybopsis meeki, however, appeared to respond to a specific spawning cue as hatch dates were unimodal with a peak in July. These results fill a gap in current knowledge of these imperilled species that can be used to guide management decisions.


Assuntos
Cyprinidae/fisiologia , Estágios do Ciclo de Vida , Animais , Cyprinidae/crescimento & desenvolvimento , Dieta/veterinária , Missouri , Membrana dos Otólitos/crescimento & desenvolvimento , Reprodução , Rios
12.
Drug Alcohol Depend ; 153: 29-36, 2015 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-26118833

RESUMO

BACKGROUND: d-Methamphetamine (METH) addiction is a serious public health concern for which successful treatment remains elusive. Immunopharmacotherapy has been shown to attenuate locomotor and thermoregulatory effects of METH. The current study investigated whether active vaccination against METH could alter intravenous METH self-administration in rats. METHODS: Male Sprague-Dawley rats (Experiment 1: N=24; Experiment 2: N=18) were vaccinated with either a control keyhole-limpet hemocyanin conjugate vaccine (KLH) or a candidate anti-METH vaccine (MH6-KLH) or. Effects of vaccination on the acquisition of METH self-administration under two dose conditions (0.05, 0.1mg/kg/inf) and post-acquisition dose-substitution (0, 0.01, 0.05, 0.20mg/kg/inf, Experiment 1; 0.01, 0.05, 0.10, 0.15mg/kg/inf, Experiment 2) during steady-state responding were investigated. Plasma METH concentrations were determined 30min after an acute challenge dose of 3.2mg/kg METH. RESULTS: Active vaccination inhibited the acquisition of METH self-administration under the 0.1mg/kg/inf dose condition, with 66% of the MH6-KLH-vaccinated rats compared to 100% of the controls reaching criteria, and produced transient and dose-dependent effects on self-administration during the maintenance phase. Under the 0.05mg/kg/inf dose condition, MH6-KLH-vaccinated rats initially self-administered more METH than controls, but then self-administration decreased across the acquisition phase relative to controls; a subsequent dose-response assessment confirmed that MH6-KLH-vaccinated rats failed to acquire METH self-administration. Finally, plasma METH concentrations were higher in MH6-KLH-vaccinated rats compared to controls after an acute METH challenge, and these were positively correlated with antibody titers. CONCLUSIONS: These data demonstrate that active immunopharmacotherapy for METH attenuates the acquisition of METH self-administration.


Assuntos
Comportamento Aditivo/prevenção & controle , Hemocianinas/administração & dosagem , Metanfetamina/análogos & derivados , Metanfetamina/administração & dosagem , Vacinação/métodos , Animais , Comportamento Aditivo/psicologia , Relação Dose-Resposta a Droga , Infusões Intravenosas , Masculino , Metanfetamina/antagonistas & inibidores , Ratos , Ratos Sprague-Dawley , Autoadministração , Resultado do Tratamento , Vacinas/administração & dosagem
13.
Phys Rev Lett ; 114(16): 162501, 2015 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-25955048

RESUMO

It has been understood since 1897 that accelerating charges must emit electromagnetic radiation. Although first derived in 1904, cyclotron radiation from a single electron orbiting in a magnetic field has never been observed directly. We demonstrate single-electron detection in a novel radio-frequency spectrometer. The relativistic shift in the cyclotron frequency permits a precise electron energy measurement. Precise beta electron spectroscopy from gaseous radiation sources is a key technique in modern efforts to measure the neutrino mass via the tritium decay end point, and this work demonstrates a fundamentally new approach to precision beta spectroscopy for future neutrino mass experiments.

14.
Ann Oncol ; 24(4): 924-30, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23233650

RESUMO

BACKGROUND: This phase II, open-label, multicentre study aimed to evaluate changes in cell proliferation and biomarkers, as well as efficacy of lapatinib in treatment-naïve patients with HER-2-negative primary breast cancer. PATIENTS AND METHODS: Patients received 1500 mg lapatinib for 28-42 days before surgery with repeat biopsies and measurements. The primary end point was inhibition of cell proliferation measured by Ki67; the secondary end points included clinical response, adverse events and changes in FOXO3a, FOXM1, p-AKT and HER-3. RESULTS: Overall, there was no significant reduction in Ki67 with treatment (assessment carried out in 28 of 31 subjects enrolled). However, four patients (14%) showed a reduction in Ki67 ≥50%. Four of 25 patients (16%) had a partial response to treatment judged by sequential ultrasound measurements. Response, in terms of either Ki67 or ultrasound, did not relate to changes in any biomarker assessed at baseline, including the estrogen receptor (ER) and epidermal growth factor receptor (EGFR). However, all four clinical responders were HER-3 positive, as were three of four Ki67 responders. CONCLUSIONS: Overall, a pre-surgical course of lapatinib monotherapy had little effect on this group of patients; however, in subsets of patients, especially those with HER-3-positive tumors, we observed either reduction in proliferation (Ki67) or tumor size; EGFR/ER status had no impact.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Quinazolinas/administração & dosagem , Adulto , Idoso , Biópsia , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Receptores ErbB/metabolismo , Feminino , Proteína Forkhead Box M1 , Proteína Forkhead Box O3 , Fatores de Transcrição Forkhead/metabolismo , Humanos , Antígeno Ki-67/metabolismo , Lapatinib , Pessoa de Meia-Idade , Proteína Oncogênica v-akt/metabolismo , Receptor ErbB-2/genética , Receptor ErbB-3/metabolismo , Receptores de Estrogênio/metabolismo
15.
Drug Alcohol Depend ; 127(1-3): 248-53, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22832282

RESUMO

BACKGROUND: The substituted cathinone compound known as mephedrone (4-methylmethcathinone; 4-MMC) has become popular with recreational users of psychomotor-stimulant compounds. Only recently have the first preclinical studies provided information about this drug in the scientific literature; nevertheless, media reports have led to drug control actions in the UK and across several US states. Rodent studies indicate that 4-MMC exhibits neuropharmacological similarity to 3,4-methylenedioxymethamphetamine (MDMA) and prompt investigation of the thermoregulatory, cardiac and locomotor effects of 4-MMC. This study focuses on the role of ambient temperature, which has been shown to shift the effects of MDMA from hyperthermic to hypothermic. METHODS: Male Sprague-Dawley rats were monitored after subcutaneous administration of 4-MMC (1.0-5.6 mg/kg) using an implantable radiotelemetry system under conditions of low (20 °C) and high (30 °C) ambient temperature. RESULTS: A pharmacokinetic study found a T(max) of 0.25 h and a C(max) of 1206 ng/ml after 5.6 mg/kg 4-MMC. A dose-dependent reduction of body temperature was produced by 4-MMC at 20 °C but there was no temperature change at 30 °C. Increased locomotor activity was observed after 4-MMC administration under both ambient temperatures, however, significantly more activity was observed at 30 °C. Heart rate was slowed by 1.0 and 5.6 mg/kg 4-MMC at 20°C, and was slower in the 30 °C vs. 20 °C condition across all treatments. CONCLUSION: These results show that the cathinone analog 4-MMC exhibits in vivo thermoregulatory properties that are distinct from those produced by MDMA.


Assuntos
Regulação da Temperatura Corporal/efeitos dos fármacos , Temperatura Corporal/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Drogas Ilícitas/farmacologia , Metanfetamina/análogos & derivados , Atividade Motora/efeitos dos fármacos , Animais , Temperatura Corporal/fisiologia , Regulação da Temperatura Corporal/fisiologia , Relação Dose-Resposta a Droga , Frequência Cardíaca/fisiologia , Masculino , Metanfetamina/farmacologia , Atividade Motora/fisiologia , Ratos , Ratos Sprague-Dawley , Temperatura
16.
Plant Dis ; 97(4): 517-529, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30722233

RESUMO

Rhodococcus fascians is a phytopathogenic actinobacterium which causes leafy galls and other plant distortions that result in economically significant losses to nurseries producing ornamental plants. Traditional assays for detection and identification are time-consuming and laborious. We developed a rapid polymerase chain reaction (PCR) diagnostic assay based on two primer pairs, p450 and fas, which target the fasA and fasD genes, respectively, that are essential for pathogenicity. We also developed a faster, more convenient, loop-mediated isothermal amplification (LAMP) assay targeting the fasR gene, which regulates expression of virulence genes. Both assays were evaluated for sensitivity and specificity in vitro and in planta. The p450 and fas primers amplified DNA only from pure cultures of pathogenic reference isolates of R. fascians. Nonpathogenic isolates and 51 other plant-associated bacteria were not amplified. The PCR primers correctly detected pathogenic R. fascians from 73 of 75 (97%) bacterial strains isolated from naturally infected plants. The PCR assay correctly discriminated between pathogenic R. fascians and other bacteria in 132 of 139 (95%) naturally infected plants, and in 34 of 34 (100%) artificially inoculated plants. The fas primers were slightly more accurate than the p450 primers. The LAMP assay accurately detected pathogenic R. fascians in 26 of 28 (93%) naturally infected plants and did not react with 23 asymptomatic plants. The LAMP primers also amplified product for DNA extracts of 40 of 41 bacterial strains isolated from plants with leafy galls. The detection limit of both the PCR and LAMP assays was approximately 103 CFU/30-µl reaction. These new tools allow fast, reliable, and accurate detection of R. fascians in vitro and in planta. The LAMP assay in particular is a significant advancement in rapid R. fascians diagnostics, and enables those with limited laboratory facilities to confirm the presence of this pathogen in infected plants.

17.
Drug Alcohol Depend ; 121(1-2): 90-6, 2012 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-21899959

RESUMO

BACKGROUND: Some epidemiological and cessation studies suggest physical exercise attenuates or prevents recreational drug use in humans. Preclinical studies indicate that wheel activity reduces cocaine self-administration in rats; this may, however, require the establishment of compulsive wheel activity. METHODS: Effects of concurrent wheel activity on intravenous d-methamphetamine (METH) self-administration were examined in male Wistar and Sprague Dawley rats with negligible prior wheel experience. Wistar rats self-administered METH (0.05 mg/kg/inf) under a fixed-ratio 1 (FR1) schedule with concurrent access to an activity wheel during sessions 1-14, 8-21 or 15-21. Control rats which did not self-administer METH had access to an activity wheel during sessions 1-14, 8-21 or 15-28. Sprague Dawley rats self-administered METH (0.1 mg/kg/inf) under FR1 for 14 sessions with either concurrent access to a locked or an unlocked activity wheel. RESULTS: METH self-administration was lower when the wheel was available concurrently from the start of self-administration training in both strains, even though Sprague Dawley rats self-administered twice as many METH infusions and ran one-sixth as much on the wheel compared to Wistar rats. Wheel access initiated after 7 or 14 days had no effect on METH self-administration in Wistar rats. Wheel activity was significantly reduced in these groups compared with the group with concurrent wheel and METH access for the first 14 sessions. CONCLUSIONS: These data show that METH self-administration is reduced by exercise if initiated from the start of self-administration and that prior METH self-administration experience interferes with the value of exercise as a reinforcer.


Assuntos
Comportamento Animal/efeitos dos fármacos , Estimulantes do Sistema Nervoso Central/administração & dosagem , Metanfetamina/administração & dosagem , Atividade Motora/efeitos dos fármacos , Condicionamento Físico Animal/fisiologia , Animais , Infusões Intravenosas , Masculino , Ratos , Ratos Sprague-Dawley , Ratos Wistar , Reforço Psicológico , Autoadministração
18.
Phys Rev Lett ; 107(14): 141301, 2011 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-22107183

RESUMO

Fifteen months of cumulative CoGeNT data are examined for indications of an annual modulation, a predicted signature of weakly interacting massive particle (WIMP) interactions. Presently available data support the presence of a modulated component of unknown origin, with parameters prima facie compatible with a galactic halo composed of light-mass WIMPs. Unoptimized estimators yield a statistical significance for a modulation of ∼2.8σ, limited by the short exposure.

20.
J Thromb Haemost ; 9(11): 2215-20, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21914124

RESUMO

BACKGROUND: It is recommended that warfarin therapy should be managed through an anticoagulation monitoring service to minimize the risk of bleeding and subsequent thromboembolic events. There are few studies in Sub-Saharan Africa that describe warfarin management in spite of the high incidence of venous thromboembolism (VTE) and rheumatic heart disease. OBJECTIVE: To examine the feasibility of the Moi Teaching and Referral Hospital anticoagulation monitoring service and compare its performance with clinics in resource-rich settings. METHODS: A retrospective chart review compared the percentage time in the therapeutic range (TTR) and rates of bleeding and thromboembolic events to published performance targets using the inference on proportions test. Wilcoxon's rank sum analyses were used to establish predictors of TTR. RESULTS: For the 178 patients enrolled, the mean TTR was 64.6% whereas the rates of major bleeds and thromboembolic events per year were 1.25% and 5%, respectively. In the primary analysis, no statistically significant differences were found between the results of TTR, major bleeds and thromboembolic events for the clinic and published performance rates. In the secondary analysis, having an artificial heart valve and a duration of follow-up of > 120 days were positively associated with a higher TTR (P < 0.05) whereas venous thromboembolism, history of tuberculosis, HIV and a duration of follow-up of < 120 days were associated with having a lower TTR (P < 0.05). CONCLUSIONS: The performance of the MTRH anticoagulation clinic is non-inferior to published metrics on the performance of clinics in resource-rich settings.


Assuntos
Anticoagulantes/uso terapêutico , Recursos em Saúde/normas , Farmacêuticos/normas , Tromboembolia Venosa/tratamento farmacológico , Monitoramento de Medicamentos , Recursos em Saúde/economia , Recursos em Saúde/estatística & dados numéricos , Humanos , Quênia , Farmacêuticos/economia , Estudos Retrospectivos , Cardiopatia Reumática , População Rural , Tromboembolia Venosa/epidemiologia , Varfarina/uso terapêutico
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