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1.
AIDS Behav ; 26(9): 2881-2890, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35218452

RESUMO

Daily oral pre-exposure prophylaxis (PrEP) offers effective HIV prevention. In South Africa, PrEP is publicly available, but use among young women remains low. We explored young women's perceptions of PrEP to inform a gender-focused intervention to promote PrEP uptake. Six focus group discussions and eight in-depth interviews exploring perceptions of PrEP were conducted with forty-six women not using PrEP, ages 18-25, from central Durban. Data were thematically analyzed using a team-based consensus approach. The study was conducted among likely PrEP users: women were highly-educated, with 84.8% enrolled in post-secondary education. Qualitative data revealed intersecting social stigmas related to HIV and women's sexuality. Women feared that daily PrEP pills would be confused with anti-retroviral treatment, creating vulnerability to misplaced HIV stigma. Women also anticipated that taking PrEP could expose them to assumptions of promiscuity from the community. To address these anticipated community-level reactions, women suggested community-facing interventions to reduce the burden on young women considering PrEP. Concerns around PrEP use in this group of urban, educated women reflects layered stigmas that may inhibit future PrEP use. Stigma-reducing strategies, such as media campaigns and educational interventions directed at communities who could benefit from PrEP, should re-frame PrEP as an empowering and responsible choice for young women.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Profilaxia Pré-Exposição , Adolescente , Adulto , Fármacos Anti-HIV/uso terapêutico , Feminino , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Humanos , Sexualidade , Estigma Social , África do Sul/epidemiologia , Adulto Jovem
2.
J Antimicrob Chemother ; 75(5): 1091-1098, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-31943008

RESUMO

BACKGROUND: Countries are currently seeking evidence-informed policy options to address antimicrobial resistance (AMR). While rigorous evaluations of AMR interventions are the ideal, they are far from the current reality. Additionally, poor reporting and documentation of AMR interventions impede efforts to use evidence to inform future evaluations and policy interventions. OBJECTIVES: To critically evaluate reporting quality gaps in AMR intervention research. METHODS: To evaluate the reporting quality of studies, we conducted a descriptive synthesis and comparative analysis of studies that were included in a recent systematic review of government policy interventions aiming to reduce human antimicrobial use. Reporting quality was assessed using the SQUIRE 2.0 checklist of 18 items for reporting system-level interventions to improve healthcare. Two reviewers independently applied the checklist to 66 studies identified in the systematic review. RESULTS: None of the studies included complete information on all 18 SQUIRE items (median score = 10, IQR = 8-11). Reporting quality varied across SQUIRE items, with 3% to 100% of studies reporting the recommended information for each SQUIRE item. Only 20% of studies reported the elements of the intervention in sufficient detail for replication and only 24% reported the mechanism through which the intervention was expected to work. CONCLUSIONS: Gaps in the reporting of impact evaluations pose challenges for interpreting and replicating study results. Failure to improve reporting practice of policy evaluations is likely to impede efforts to tackle the growing health, social and economic threats posed by AMR.


Assuntos
Antibacterianos , Anti-Infecciosos , Antibacterianos/uso terapêutico , Lista de Checagem , Humanos
3.
Health Res Policy Syst ; 18(1): 60, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32513200

RESUMO

Antimicrobial resistance (AMR) has the potential to threaten tens of millions of lives and poses major global economic and development challenges. As the AMR threat grows, it is increasingly important to strengthen the scientific evidence base on AMR policy interventions, to learn from existing policies and programmes, and to integrate scientific evidence into the global AMR response.While rigorous evaluations of AMR policy interventions are the ideal, they are far from the current reality. To strengthen this evidence base, we describe a framework for planning, conducting and disseminating research on AMR policy interventions. The framework identifies challenges in AMR research, areas for enhanced coordination and cooperation with decision-makers, and best practices in the design of impact evaluations for AMR policies.This framework offers a path forward, enabling increased local and global cooperation, and overcoming common limitations in existing research on AMR policy interventions.


Assuntos
Gestão de Antimicrobianos , Farmacorresistência Bacteriana , Pesquisa sobre Serviços de Saúde , Antibacterianos/uso terapêutico , Política de Saúde , Humanos
4.
Int Nurs Rev ; 67(3): 334-340, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32484258

RESUMO

AIM: This report from the field describes impressions of the initial impact of bilateral, multi-sectoral field-based activities undertaken to strengthen International Organization for Migration/United Nations Migration Agency and US-based nurses' capacity to address complex clinical, social and cultural challenges experienced by refugees in resettlement. Authors comment on the defined and thorough health assessment process that refugees go through prior to resettlement, and focus on the essential nursing role in the health assessment process and continuum of care. The development of the interdisciplinary and collaborative partnership is described as well as next steps to move the partnership forward. BACKGROUND: In 2017, International Organization for Migration/United Nations Migration Agency and the University of Minnesota, guided by experts from the United States Centers for Disease Control and Prevention, began a unique bilateral Intergovernmental-Academic partnership to enhance the health care of refugees. A key component was to strengthen nursing care of refugees through the standardization of clinical practice and nursing leadership. SOURCES OF EVIDENCE: Listening sessions, direct interaction between International Organization for Migration/United Nations Migration Agency and US-based refugee resettlement stakeholders, patterns in resettlement. CONCLUSION AND IMPLICATIONS FOR NURSING AND HEALTH POLICY: The report highlights the potential public health impact of a bilateral and collaborative initiative that develops and bridges key points in the migration and health trajectory of people with refugee status. Separated by geography, context and scope of work, health professionals in different roles in varied worldwide settings with a spectrum of resources may not fully understand the work of each other. Project activities were a platform through which US-based and internationally based nurses established mutuality, reciprocity and equity as partners. By strengthening systems and resources, the partnership reinforces the abilities of nurses who engage in this important work, to optimize health and wellbeing of people with refugee status.


Assuntos
Emigração e Imigração , Agências Internacionais/estatística & dados numéricos , Papel do Profissional de Enfermagem/psicologia , Cuidados de Enfermagem/psicologia , Recursos Humanos de Enfermagem/psicologia , Recursos Humanos de Enfermagem/estatística & dados numéricos , Refugiados , Adulto , Feminino , Humanos , Cooperação Internacional , Masculino , Pessoa de Meia-Idade , Estados Unidos
5.
Clin Exp Allergy ; 47(9): 1214-1222, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28471517

RESUMO

BACKGROUND: The Duffy antigen receptor for chemokines (DARC) is an atypical receptor that regulates pro-inflammatory cytokines. However, the role of DARC in asthma pathophysiology is unknown. OBJECTIVE: To determine the role of DARC in allergic airways disease in mice, and the association between DARC single nucleotide polymorphisms (SNPs) and clinical outcomes in patients with asthma. METHODS: Mice with targeted disruption of the Darc gene (Darc∆E2 ) or WT mice were challenged over 3 weeks with house dust mite (HDM) antigen. Allergic airways disease was assessed 24 hours and 7 days following the final challenge. Additionally, associations between DARC SNPs and clinical outcomes were analysed in a cohort of poorly controlled asthmatics. RESULTS: Total airway inflammation following HDM did not differ between Darc∆E2 and WT mice. At 24 hours, Darc∆E2 mice had increased airway hyperresponsiveness; however, at 7 days airway hyperresponsiveness had completely resolved in Darc∆E2 but persisted in WT mice. In poorly controlled asthmatics, DARC SNPs were associated with worse asthma control at randomization and subsequent increased risk of healthcare utilization (odds ratio 3.13(1.37-7.27), P=.0062). CONCLUSIONS AND CLINICAL RELEVANCE: Our animal model and human patient data suggest a novel role for DARC in the temporal regulation in asthma pathophysiology and symptoms.


Assuntos
Asma , Quimiocinas , Sistema do Grupo Sanguíneo Duffy , Receptores de Superfície Celular , Animais , Feminino , Humanos , Masculino , Camundongos , Antígenos de Dermatophagoides/imunologia , Asma/diagnóstico , Asma/etiologia , Asma/metabolismo , Quimiocinas/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Sistema do Grupo Sanguíneo Duffy/genética , Sistema do Grupo Sanguíneo Duffy/metabolismo , Expressão Gênica , Loci Gênicos , Leucócitos/imunologia , Leucócitos/metabolismo , Leucócitos/patologia , Camundongos Knockout , Neutrófilos/imunologia , Neutrófilos/metabolismo , Neutrófilos/patologia , Aceitação pelo Paciente de Cuidados de Saúde , Avaliação de Resultados da Assistência ao Paciente , Fenótipo , Polimorfismo de Nucleotídeo Único , Prognóstico , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Hipersensibilidade Respiratória/diagnóstico , Hipersensibilidade Respiratória/etiologia , Hipersensibilidade Respiratória/metabolismo , Mucosa Respiratória/imunologia , Mucosa Respiratória/metabolismo , Índice de Gravidade de Doença
6.
AIDS Behav ; 21(3): 905-922, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27807792

RESUMO

Integration of sexual and reproductive health within HIV care services is a promising strategy for increasing access to family planning and STI services and reducing unwanted pregnancies, perinatal HIV transmission and maternal and infant mortality among people living with HIV and their partners. We conducted a Phase II randomized futility trial of a multi-level intervention to increase adherence to safer sex guidelines among those wishing to avoid pregnancy and adherence to safer conception guidelines among those seeking conception in newly-diagnosed HIV-positive persons in four public-sector HIV clinics in Cape Town. Clinics were pair-matched and the two clinics within each pair were randomized to either a three-session provider-delivered enhanced intervention (EI) (onsite contraceptive services and brief milieu intervention for staff) or standard-of-care (SOC) provider-delivered intervention. The futility analysis showed that we cannot rule out the possibility that the EI intervention has a 10 % point or greater success rate in improving adherence to safer sex/safer conception guidelines than does SOC (p = 0.573), indicating that the intervention holds merit, and a larger-scale confirmatory study showing whether the EI is superior to SOC has merit.


Assuntos
Infecções por HIV/terapia , Política de Saúde , Saúde Reprodutiva , Comportamento Sexual , Saúde Sexual , Serviços de Planejamento Familiar , Feminino , Infecções por HIV/transmissão , Humanos , Masculino , Gravidez , Setor Público , Sexo Seguro , Parceiros Sexuais , África do Sul/epidemiologia
7.
Heredity (Edinb) ; 112(6): 588-95, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24448564

RESUMO

Dramatic changes in the North American landscape over the last 12 000 years have shaped the genomes of the small mammals, such as the white-footed mouse (Peromyscus leucopus), which currently inhabit the region. However, very recent interactions of populations with each other and the environment are expected to leave the most pronounced signature on rapidly evolving nuclear microsatellite loci. We analyzed landscape characteristics and microsatellite markers of P. leucopus populations along a transect from southern Ohio to northern Michigan, in order to evaluate hypotheses about the spatial distribution of genetic heterogeneity. Genetic diversity increased to the north and was best approximated by a single-variable model based on habitat availability within a 0.5-km radius of trapping sites. Interpopulation differentiation measured by clustering analysis was highly variable and not significantly related to latitude or habitat availability. Interpopulation differentiation measured as FST values and chord distance was correlated with the proportion of habitat intervening, but was best explained by agricultural distance and by latitude. The observed gradients in diversity and interpopulation differentiation were consistent with recent habitat availability being the major constraint on effective population size in this system, and contradicted the predictions of both the postglacial expansion and core-periphery hypotheses.


Assuntos
Meio Ambiente , Interação Gene-Ambiente , Estruturas Genéticas , Variação Genética , Peromyscus/genética , Animais , Canadá , Análise por Conglomerados , Feminino , Deriva Genética , Genética Populacional , Geografia , Masculino , Camundongos , Análise Espacial , Estados Unidos
8.
medRxiv ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38978669

RESUMO

Background: Freezing of gait (FOG) is a debilitating symptom of Parkinson's disease (PD) that is often refractory to medication. Pathological prolonged beta bursts within the subthalamic nucleus (STN) are associated with both worse impairment and freezing behavior in PD, which are improved with deep brain stimulation (DBS). The goal of the current study was to investigate the feasibility, safety, and tolerability of beta burst-driven adaptive DBS (aDBS) for FOG in PD. Methods: Seven individuals with PD were implanted with the investigational Summit™ RC+S DBS system (Medtronic, PLC) with leads placed bilaterally in the STN. A PC-in-the-loop architecture was used to adjust stimulation amplitude in real-time based on the observed beta burst durations in the STN. Participants performed either a harnessed stepping-in-place task or a free walking turning and barrier course, as well as clinical motor assessments and instrumented measures of bradykinesia, OFF stimulation, on aDBS, continuous DBS (cDBS), or random intermittent DBS (iDBS). Results: Beta burst driven aDBS was successfully implemented and deemed safe and tolerable in all seven participants. Gait metrics such as overall percent time freezing and mean peak shank angular velocity improved from OFF to aDBS and showed similar efficacy as cDBS. Similar improvements were also seen for overall clinical motor impairment, including tremor, as well as quantitative metrics of bradykinesia. Conclusion: Beta burst driven adaptive DBS was feasible, safe, and tolerable in individuals with PD with gait impairment and FOG.

9.
Nat Genet ; 10(3): 330-6, 1995 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7670472

RESUMO

Pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED) are dominantly inherited chondrodysplasias characterized by short stature and early-onset osteoarthrosis. The disease genes in families with PSACH and MED have been localized to an 800 kilobase interval on the short arm of chromosome 19. Recently the gene for cartilage oligomeric matrix protein (COMP) was localized to chromosome 19p13.1. In three patients with these diseases, we identified COMP mutations in a region of the gene that encodes a Ca++ binding motif. Our data demonstrate that PSACH and some forms of MED are allelic and suggest an essential role for Ca++ binding in COMP structure and function.


Assuntos
Acondroplasia/genética , Proteínas da Matriz Extracelular , Glicoproteínas/genética , Mutação , Osteocondrodisplasias/genética , Acondroplasia/diagnóstico por imagem , Acondroplasia/metabolismo , Alelos , Sequência de Aminoácidos , Sequência de Bases , Cálcio/metabolismo , Calmodulina/genética , Cartilagem , Proteína de Matriz Oligomérica de Cartilagem , Mapeamento Cromossômico , Cromossomos Humanos Par 19 , DNA Satélite/genética , Fator de Crescimento Epidérmico/genética , Feminino , Genes Dominantes , Ligação Genética , Glicoproteínas/metabolismo , Humanos , Masculino , Proteínas Matrilinas , Dados de Sequência Molecular , Osteocondrodisplasias/diagnóstico por imagem , Osteocondrodisplasias/metabolismo , Linhagem , Reação em Cadeia da Polimerase , Polimorfismo Conformacional de Fita Simples , Radiografia , Sequências Repetitivas de Ácido Nucleico
10.
Nat Genet ; 23(3): 309-13, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10610179

RESUMO

The unicellular parasite Plasmodium falciparum is the cause of human malaria, resulting in 1.7-2.5 million deaths each year. To develop new means to treat or prevent malaria, the Malaria Genome Consortium was formed to sequence and annotate the entire 24.6-Mb genome. The plan, already underway, is to sequence libraries created from chromosomal DNA separated by pulsed-field gel electrophoresis (PFGE). The AT-rich genome of P. falciparum presents problems in terms of reliable library construction and the relative paucity of dense physical markers or extensive genetic resources. To deal with these problems, we reasoned that a high-resolution, ordered restriction map covering the entire genome could serve as a scaffold for the alignment and verification of sequence contigs developed by members of the consortium. Thus optical mapping was advanced to use simply extracted, unfractionated genomic DNA as its principal substrate. Ordered restriction maps (BamHI and NheI) derived from single molecules were assembled into 14 deep contigs corresponding to the molecular karyotype determined by PFGE (ref. 3).


Assuntos
Genoma de Protozoário , Mapeamento Físico do Cromossomo/métodos , Plasmodium falciparum/genética , Animais , Cromossomos/genética , Cromossomos Artificiais de Levedura/genética , Mapeamento de Sequências Contíguas/métodos , Eletroforese em Gel de Campo Pulsado , Etiquetas de Sequências Expressas , Biblioteca Genômica , Processamento de Imagem Assistida por Computador , Cariotipagem/métodos , Óptica e Fotônica , Reprodutibilidade dos Testes , Mapeamento por Restrição/métodos , Sensibilidade e Especificidade
11.
Public Underst Sci ; 32(4): 442-458, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36515486

RESUMO

Informal learning environments play a critical role in science, technology, engineering, and mathematics learning across the lifespan and are consequential in informing public understanding and engagement. This can be difficult to accomplish in life science where expertise thresholds and logistics involved with handling biological materials can restrict access. Community laboratories are informal learning environments that provide access to the resources necessary to carry out pursuits using enabling biotechnologies. We investigate a group of these spaces in order to ascertain how this occurs-with specific attention to how material and intellectual resources are structured and shape learning. Using surveys and focus group interviews, we explore a group of these spaces located in the United States. We found that the spaces examined offer learning activities that are sufficiently scaffolded and flexible as to promote personalized and community-driven practice. We discuss these findings in relation to informal learning environment design and learning.


Assuntos
Disciplinas das Ciências Biológicas , Ciência , Biotecnologia , Laboratórios , Aprendizagem , Estados Unidos , Redes Comunitárias
12.
Nucl Med Biol ; 122-123: 108368, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37490805

RESUMO

Advanced ovarian cancer currently has few therapeutic options. Poly(ADP-ribose) polymerase (PARP) inhibitors bind to nuclear PARP and trap the protein-inhibitor complex to DNA. This work investigates a theranostic PARP inhibitor for targeted radiopharmaceutical therapy of ovarian cancer in vitro and PET imaging of healthy mice in vivo. METHODS: [77Br]RD1 was synthesized and assessed for pharmacokinetics and cytotoxicity in human and murine ovarian cancer cell lines. [76Br]RD1 biodistribution and organ uptake in healthy mice were quantified through longitudinal PET/CT imaging and ex vivo radioactivity measurements. Organ-level dosimetry following [76/77Br]RD1 administration was calculated using RAPID, an in-house platform for absorbed dose in mice, and OLINDA for equivalent and effective dose in human. RESULTS: The maximum specific binding (Bmax), equilibrium dissociation constant (Kd), and nonspecific binding slope (NS) were calculated for each cell line. These values were used to calculate the cell specific activity uptake for cell viability studies. The half maximal effective concentration (EC50) was measured as 0.17 (95 % CI: 0.13-0.24) nM and 0.46 (0.13-0.24) nM for PARP(+) and PARP(-) expressing cell lines, respectively. The EC50 was 0.27 (0.21-0.36) nM and 0.30 (0.22-0.41) nM for BRCA1(-) and BRCA1(+) expressing cell lines, respectively. When measuring the EC50 as a function of cellular activity uptake and nuclear dose, the EC50 ranges from 0.020 to 0.039 Bq/cell and 3.3-9.2 Gy, respectively. Excretion through the hepatobiliary and renal pathways were observed in mice, with liver uptake of 2.3 ± 0.4 %ID/g after 48 h, contributing to estimated absorbed dose values in mice of 19.3 ± 0.3 mGy/MBq and 290 ± 10 mGy/MBq for [77Br]RD1 and [76Br]RD1, respectively. CONCLUSION: [77Br]RD1 cytotoxicity was dependent on PARP expression and independent of BRCA1 status. The in vitro results suggest that [77Br]RD1 cytotoxicity is driven by the targeted Meitner-Auger electron (MAe) radiotherapeutic effect of the agent. Further studies investigating the theranostic potential, organ dose, and tumor uptake of [76/77Br]RD1 are warranted.


Assuntos
Neoplasias Ovarianas , Compostos Radiofarmacêuticos , Feminino , Humanos , Animais , Camundongos , Compostos Radiofarmacêuticos/farmacocinética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Medicina de Precisão , Linhagem Celular Tumoral , Distribuição Tecidual , Neoplasias Ovarianas/diagnóstico por imagem , Neoplasias Ovarianas/radioterapia
13.
Opt Express ; 20(14): 15086-92, 2012 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-22772205

RESUMO

We demonstrate steady-state focusing of coherent light through dynamic scattering media. The phase of an incident beam is controlled both spatially and temporally using a reflective, 1020-segment MEMS spatial light modulator, using a coordinate descent optimization technique. We achieve focal intensity enhancement of between 5 and 400 for dynamic media with speckle decorrelation time constants ranging from 0.4 seconds to 20 seconds. We show that this optimization approach combined with a fast spatial light modulator enables focusing through dynamic media. The capacity to enhance focal intensity despite transmission through dynamic scattering media could enable advancement in biological microscopy and imaging through turbid environments.

14.
Allergy ; 67(12): 1601-4, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23004679

RESUMO

BACKGROUND: Caveolin-1 has emerged as a critical regulator of signaling pathways involved in lung fibrosis and inflammation. METHODS: Therefore, we investigated whether caveolin-1 is deficient in asthmatic patients and in a murine model of asthma. RESULTS: Immunohistochemical analyses of endobronchial biopsies showed a remarkable loss of caveolin-1 in the lungs of asthmatic patients compared with controls. This loss was most evident in bronchial epithelial cells and associated with an increase in the expression of extracellular matrix proteins: collagen I, tenascin, and periostin. Cultured primary bronchial epithelial cells of asthmatics had lower caveolin-1 expression compared with control cells. In addition, caveolin-1 expression was significantly decreased in peripheral blood monocytes from asthma patients. The loss of caveolin-1 was also observed in a mouse model for asthma (mice sensitized and challenged with aspergillus fumigatus). CONCLUSIONS: To our knowledge, this is the first demonstration that the regulatory protein caveolin-1 is reduced in patients with asthma.


Assuntos
Asma/metabolismo , Brônquios/metabolismo , Caveolina 1/metabolismo , Células Epiteliais/metabolismo , Monócitos/metabolismo , Animais , Caveolina 1/deficiência , Modelos Animais de Doenças , Proteínas da Matriz Extracelular/metabolismo , Feminino , Humanos , Pulmão/metabolismo , Pulmão/patologia , Camundongos , Transdução de Sinais
15.
Perspect Biol Med ; 55(3): 350-61, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23179029

RESUMO

Immunology has been referred to as the science of self/non-self discrimination. Who or what is the "I" of which we often speak? It has been identified with body, brain, soul, and memories. There has been a diversity of ways to characterize the self, including denying its importance and existence, and to date no satisfactory conceptualization has been achieved. This article addresses the concept of self from an immunological perspective, a perspective that offers insights into the philosophic issues associated with the concept of self and personal identity. The article proposes that the immunological and the psychological are two aspects of one and the same self, offers criteria for an adequate conceptualization of the self, and discusses the philosophical and psychological implications of the immunological views of self. It concludes that we must move away from a simplistic, exclusively inward or mentalistic conception of the self.


Assuntos
Identificação Psicológica , Tolerância Imunológica , Autoimagem , Estado de Consciência , Humanos , Memória , Modelos Psicológicos , Percepção , Pessoalidade
16.
Nat Med ; 3(1): 80-3, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8986746

RESUMO

An estimated 300-500 million new infections and 1.5-2.7 million deaths attributed to malaria occur annually in the developing world, and every year tens of millions of travelers from countries where malaria is not transmitted visit countries with malaria. Because the parasites that cause malaria have developed resistance to many antimalarial drugs, new methods for prevention are required. Intraperitoneal injection into mice of one dose of 150 ng (approximately 7.5 micrograms per kg body weight) recombinant mouse interleukin-12 (rmIL-12) 2 days before challenge with Plasmodium yoelii sporozoites protects 100% of mice against malaria. We report that one subcutaneous injection of 10 micrograms/kg recombinant human IL-12 (rhIL-12) 2 days before challenge with P. cynomolgi sporozoites protected seven of seven rhesus monkeys. Protection was associated with marked increases in plasma levels of interferon-gamma (IFN-gamma), and relative increases of lymphoid cell messenger RNA coding for IFN-gamma and several other cytokines. We speculate that rIL-12 protects monkeys through IFN-gamma-dependent elimination of P. cynomolgi-infected hepatocytes. This first report of rIL-12-induced protection of primates against an infectious agent supports assessment of rhIL-12 for immunoprophylaxis of human malaria.


Assuntos
Interleucina-12/farmacologia , Malária/prevenção & controle , Plasmodium cynomolgi , Plasmodium yoelii , Animais , Relação Dose-Resposta a Droga , Interferon gama/sangue , Interferon gama/efeitos dos fármacos , Interferon gama/genética , Interleucina-12/sangue , Interleucinas/genética , Interleucinas/metabolismo , Leucócitos Mononucleares/metabolismo , Macaca mulatta/imunologia , Reação em Cadeia da Polimerase , RNA Mensageiro/metabolismo , Proteínas Recombinantes/farmacologia , Fatores de Tempo , Fator de Necrose Tumoral alfa/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
17.
J Exp Med ; 183(4): 1739-46, 1996 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-8666931

RESUMO

Despite efforts to develop vaccines that protect against malaria by inducing CD8+ T cells that kill infected hepatocytes, no subunit vaccine has been shown to circumvent the genetic restriction inherent in this approach, and little is known about the interaction of subunit vaccine-induced immune effectors and infected hepatocytes. We now report that immunization with plasmid DNA encoding the plasmodium yoelii circumsporozoite protein protected one of five strains of mice against malaria (H-2d, 75%); a PyHEP17 DNA vaccine protected three of the five strains (H-2a, 71%; H-2k, 54%; H-2d, 26%); and the combination protected 82% of H-2a, 90% of H-2k, and 88% of H-2d mice. Protection was absolutely dependent on CD8+ T cells, INF-gamma, or nitric oxide. These data introduce a new target of protective preerythrocytic immune responses, PyHEP 17 and its P. falciparum homologue, and provide a realistic perspective on the opportunities and challenges inherent in developing malaria vaccines that target the infected hepatocyte.


Assuntos
DNA de Protozoário/uso terapêutico , Imunização , Vacinas Antimaláricas/uso terapêutico , Malária/prevenção & controle , Vacinas Sintéticas/uso terapêutico , Animais , Linfócitos T CD8-Positivos/imunologia , Feminino , Genes de Protozoários , Imunidade/genética , Interferon gama , Depleção Linfocítica , Camundongos/genética , Óxido Nítrico , Plasmídeos/uso terapêutico , Plasmodium yoelii/genética , Plasmodium yoelii/imunologia , Proteínas de Protozoários/genética , Proteínas de Protozoários/imunologia , Especificidade da Espécie
18.
J Exp Med ; 182(5): 1435-45, 1995 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-7595214

RESUMO

Vaccines designed to protect against malaria by inducing CD8+ cytotoxic T lymphocytes (CTL) in individuals of diverse HLA backgrounds must contain multiple conserved epitopes from various preerythrocytic-stage antigens. Plasmodium falciparum sporozoite surface protein 2 (PfSSP2) is considered an important antigen for inclusion in such vaccines, because CD8+ CTL against the P. yoelii SSP2 protect mice against malaria by eliminating infected hepatocytes. To develop PfSSP2 as a component of malaria vaccines, we investigated the presence of anti-PfSSP2 CTL in two HLA-B8+ volunteers immunized with irradiated P. falciparum sporozoites and characterized their CTL responses using PfSSP2-derived 15-amino acid peptides bearing the HLA-B8-binding motif. Peripheral blood mononuclear cells from both volunteers stimulated with recombinant vaccinia expressing PfSSP2 displayed antigen-specific, genetically restricted, CD8+ T cell-dependent CTL activity against autologous target cells expressing PfSSP2. Of the five HLA-B8 motif-bearing 15-mers identified in the PfSSP2 sequence, two peptides sharing a 10-amino acid overlap sensitized HLA-B8-matched target cells from both volunteers for lysis by peptide-stimulated effectors. The CTL activity was HLA-B8 restricted and dependent on CD8+ T cells. Analysis of the three shorter peptides representing HLA-B8 motif-bearing sequences within the two positive peptides for their ability to bind to HLA-B8 in vitro, and to sensitize target cells for lysis by effectors stimulated with the 15-mers, identified two overlapping HLA-B8-restricted CTL epitopes. Available data indicate that the sequence of one CTL epitope is conserved and the other is variant among P. falciparum isolates. Circulating activated CTL against the conserved epitope could be directly identified in one of the two volunteers. The identification of two HLA-B8-restricted CTL epitopes on PfSSP2 provides data critical to developing an epitope-based anti-liver stage malaria vaccine.


Assuntos
Antígenos de Protozoários/imunologia , Epitopos/imunologia , Antígeno HLA-B8/imunologia , Vacinas Antimaláricas/imunologia , Plasmodium falciparum/imunologia , Proteínas de Protozoários/imunologia , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Animais , Culicidae/parasitologia , Humanos , Imunização , Ativação Linfocitária , Malária Falciparum/prevenção & controle , Dados de Sequência Molecular , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/imunologia , Plasmodium falciparum/crescimento & desenvolvimento , Plasmodium falciparum/efeitos da radiação , Ligação Proteica , Vacinas Atenuadas/imunologia , Vacinas Sintéticas/imunologia
19.
J Exp Med ; 171(3): 763-73, 1990 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-1689762

RESUMO

Irradiated malaria sporozoites can induce CD8+ T cells that are required for protection against infection. However, the parasite antigens targeted by this immune response are unknown. We have discovered a 16-amino acid epitope from the Plasmodium yoelii circumsporozoite (CS) protein that is recognized by cytotoxic T cells from immune mice. Lymphocytes stimulated with this peptide can kill P. yoelii liver stage parasites in vitro in an MHC-restricted, antigen-specific manner. Thus, epitopes from the CS protein are presented on the surface of infected hepatocytes and can be targets for T cells, even though intact CS protein has not been detected on the surface of the infected hepatocyte. A vaccine that induced CTL to parasite antigens might protect humans against malaria by eliminating liver stage parasites.


Assuntos
Fígado/parasitologia , Fragmentos de Peptídeos/imunologia , Plasmodium yoelii/imunologia , Proteínas de Protozoários/imunologia , Linfócitos T Citotóxicos/imunologia , Animais , Epitopos/análise , Feminino , Imunização , Fígado/imunologia , Malária/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Vacinas/imunologia
20.
J Vet Intern Med ; 24(3): 647-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20384957

RESUMO

BACKGROUND: Voriconazole has a broader spectrum of activity in comparison to fluconazole, itraconazole, and amphotericin B. Little documentation regarding appropriate dosing, efficacy, or adverse effects exists for cats. Neurologic adverse effects have been reported as a result of administration in other species. HYPOTHESIS: Voriconazole administration resulted in neurologic abnormalities in 3 cats. ANIMALS: Three cats that received voriconazole. METHODS: Observational study of adverse effects associated with voriconazole administration. RESULTS: All 3 cats had ataxia, which in 2 cats progressed to paraplegia of the rear limbs. Two of the cats had visual abnormalities including mydriasis, decreased to absent pupillary light responses, and decreased menace response. Arrhythmia and hypokalemia were noted in 2 separate cats. CONCLUSIONS AND CLINICAL IMPORTANCE: Voriconazole has potential neurologic adverse effects in cats. Additional information regarding pharmacokinetics of the drug in this species must be gathered to help determine how it can be dosed most effectively with minimal adverse effects.


Assuntos
Antifúngicos/efeitos adversos , Doenças do Gato/induzido quimicamente , Doenças do Sistema Nervoso Central/veterinária , Pirimidinas/efeitos adversos , Triazóis/efeitos adversos , Animais , Aspergilose/tratamento farmacológico , Doenças do Gato/tratamento farmacológico , Gatos , Doenças do Sistema Nervoso Central/induzido quimicamente , Feminino , Rinite/tratamento farmacológico , Rinite/microbiologia , Rinite/veterinária , Voriconazol
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