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New neurones are generated throughout life in the mammalian brain in a process known as adult hippocampal neurogenesis (AHN). Since this phenomenon grants a high degree of neuroplasticity influencing learning and memory, identifying factors that regulate AHN may be important for ameliorating age-related cognitive decline. Calorie restriction (CR) has been shown to enhance AHN and improve memory, mediated by the stomach hormone, ghrelin. Intermittent fasting (IF), a dietary strategy offering more flexibility than conventional CR, has also been shown to promote aspects of AHN. The 5:2 diet is a popular form of IF; however, its effects on AHN are not well characterised. To address this, we quantified AHN in adolescent and adult wild-type and ghrelin-receptor-deficient mice following 6 weeks on a 5:2 diet. We report an age-related decline in neurogenic processes. However, the 5:2 diet does not increase AHN nor enhance memory performance, suggesting that this specific form of IF is ineffective in promoting brain plasticity to support learning.
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Grelina , Memória Espacial , Camundongos , Animais , Dieta , Neurogênese , Hipocampo , MamíferosRESUMO
BACKGROUND: Pseudomonas aeruginosa is a frequent pathogen isolated from bacterial bloodstream infection (BSI) and is associated with high mortality. To survive in the blood, P aeruginosa must resist the bactericidal action of complement (ie, serum killing). Antibodies usually promote serum killing through the classical complement pathway; however, "cloaking antibodies" (cAbs) have been described, which paradoxically protect bacteria from serum killing. The relevance of cAbs in P aeruginosa BSI is unknown. METHODS: Serum and P aeruginosa were collected from a cohort of 100 patients with BSI. Isolates were tested for sensitivity to healthy control serum (HCS). cAb prevalence was determined in sera. Patient sera were mixed with HCS to determine if killing of the matched isolate was inhibited. RESULTS: Overall, 36 patients had elevated titers of cAbs, and 34 isolates were sensitive to HCS killing. Fifteen patients had cAbs and HCS-sensitive isolates; of these patients, 14 had serum that protected their matched bacteria from HCS killing. Patients with cAbs were less likely to be neutropenic or have comorbidities. CONCLUSIONS: cAbs are prevalent in patients with P aeruginosa BSI and allow survival of otherwise serum-sensitive bacteria in the bloodstream. Generation of cAbs may be a risk factor for the development of BSI.
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Anticorpos Antibacterianos , Bacteriemia , Infecções por Pseudomonas , Pseudomonas aeruginosa , Humanos , Pseudomonas aeruginosa/imunologia , Infecções por Pseudomonas/imunologia , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Bacteriemia/microbiologia , Bacteriemia/imunologia , Idoso , Anticorpos Antibacterianos/sangue , Adulto , Idoso de 80 Anos ou mais , Estudos de CoortesRESUMO
BACKGROUND: Pseudomonas aeruginosa is a multidrug-resistant pathogen causing recalcitrant pulmonary infections in people with cystic fibrosis (pwCF). Cystic fibrosis transmembrane conductance regulator (CFTR) modulators have been developed that partially correct the defective chloride channel driving disease. Despite the many clinical benefits, studies in adults have demonstrated that while P. aeruginosa sputum load decreases, chronic infection persists. Here, we investigate how P. aeruginosa in pwCF may change in the altered lung environment after CFTR modulation. METHODS: P. aeruginosa strains (n = 105) were isolated from the sputum of 11 chronically colonized pwCF at baseline and up to 21 months posttreatment with elexacaftor-tezacaftor-ivacaftor or tezacaftor-ivacaftor. Phenotypic characterization and comparative genomics were performed. RESULTS: Clonal lineages of P. aeruginosa persisted after therapy, with no evidence of displacement by alternative strains. We identified commonly mutated genes among patient isolates that may be positively selected for in the CFTR-modulated lung. However, classic chronic P. aeruginosa phenotypes such as mucoid morphology were sustained, and isolates remained just as resistant to clinically relevant antibiotics. CONCLUSIONS: Despite the clinical benefits of CFTR modulators, clonal lineages of P. aeruginosa persist that may prove just as difficult to manage in the future, especially in pwCF with advanced lung disease.
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Antibiotic resistance is a major public health threat, and alternatives to antibiotic therapy are urgently needed. Immunotherapy, particularly the blockade of inhibitory immune checkpoints, is a leading treatment option in cancer and autoimmunity. In this study, we used a murine model of Salmonella Typhimurium infection to investigate whether immune checkpoint blockade could be applied to bacterial infection. We found that the immune checkpoint T-cell immunoglobulin and ITIM domain (TIGIT) was significantly upregulated on lymphocytes during infection, particularly on CD4+ T cells, drastically limiting their proinflammatory function. Blockade of TIGIT in vivo using monoclonal antibodies was able to enhance immunity and improve bacterial clearance. The efficacy of anti-TIGIT was dependent on the capacity of the antibody to bind to Fc (fragment crystallizable) receptors, giving important insights into the mechanism of anti-TIGIT therapy. This research suggests that targeting immune checkpoints, such as TIGIT, has the potential to enhance immune responses toward bacteria and restore antibacterial treatment options in the face of antibiotic resistance.
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A hallmark of Listeria (L.) monocytogenes pathogenesis is bacterial escape from maturing entry vacuoles, which is required for rapid bacterial replication in the host cell cytoplasm and cell-to-cell spread. The bacterial transcriptional activator PrfA controls expression of key virulence factors that enable exploitation of this intracellular niche. The transcriptional activity of PrfA within infected host cells is controlled by allosteric coactivation. Inhibitory occupation of the coactivator site has been shown to impair PrfA functions, but consequences of PrfA inhibition for L. monocytogenes infection and pathogenesis are unknown. Here we report the crystal structure of PrfA with a small molecule inhibitor occupying the coactivator site at 2.0 Å resolution. Using molecular imaging and infection studies in macrophages, we demonstrate that PrfA inhibition prevents the vacuolar escape of L. monocytogenes and enables extensive bacterial replication inside spacious vacuoles. In contrast to previously described spacious Listeria-containing vacuoles, which have been implicated in supporting chronic infection, PrfA inhibition facilitated progressive clearance of intracellular L. monocytogenes from spacious vacuoles through lysosomal degradation. Thus, inhibitory occupation of the PrfA coactivator site facilitates formation of a transient intravacuolar L. monocytogenes replication niche that licenses macrophages to effectively eliminate intracellular bacteria. Our findings encourage further exploration of PrfA as a potential target for antimicrobials and highlight that intra-vacuolar residence of L. monocytogenes in macrophages is not inevitably tied to bacterial persistence.
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Listeria monocytogenes/patogenicidade , Listeriose/microbiologia , Macrófagos/microbiologia , Vacúolos/microbiologia , Virulência/fisiologia , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BLRESUMO
The feeding-related hormone, acyl-ghrelin, protects dopamine neurones in murine 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP)-based models of experimental Parkinson's disease (PD). However, the potential protective effect of acyl-ghrelin on substantia nigra pars compacta (SNpc) dopaminergic neurones and consequent behavioural correlates in the more widely used 6-hydroxydopamine (6-OHDA) rat medial forebrain bundle (MFB) lesion model of PD are unknown. To address this question, acyl-ghrelin levels were raised directly by mini-pump infusion for 7 days prior to unilateral injection of 6-OHDA into the MFB with assessment of amphetamine-induced rotations on days 27 and 35, and immunohistochemical analysis of dopaminergic neurone survival. Whilst acyl-ghrelin treatment was insufficient to elevate food intake or body weight, it attenuated amphetamine-induced circling behaviour and SNpc dopamine neurone loss induced by 6-OHDA. These data support the notion that elevating circulating acyl-ghrelin may be a valuable approach to slow or impair progression of neurone loss in PD.
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Doença de Parkinson , Ratos , Camundongos , Animais , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/patologia , Oxidopamina , Dopamina , Anfetamina/farmacologia , Neurônios DopaminérgicosRESUMO
Immunotherapy has revolutionized cancer therapy by reactivating tumour-resident cytotoxic lymphocytes. More recently, immunotherapy has emerged to restore immunity against infectious agents, including bacterial infections. Immunotherapy primarily targets inhibitory pathways in T cells, however interest in other effector populations, such as natural killer (NK) cells, is growing. We have previously discovered that NK cell metabolism, proliferation and activation can be neutralized through the immunosuppressive transforming growth factor (TGF)-ß pathway by inducing plasticity of NK cells and differentiation into innate lymphoid cell (ILC)1-like subsets. NK cells are also regulated through cytokine-inducible SH2-containing protein (CIS), which is induced by interleukin (IL)-15 and is a potent intracellular checkpoint suppressing NK cell survival and function. Targeting these two distinct pathways to restore NK cell function has shown promise in cancer models, but their application in bacterial infection remains unknown. Here, we investigate whether enhancement of NK cell function can improve anti-bacterial immunity, using Salmonella Typhimurium as a model. We identified conversion of NK cells to ILC1-like for the first time in the context of bacterial infection, where TGF-ß signalling contributed to this plasticity. Future study should focus on identifying further drivers of ILC1 plasticity and its functional implication in bacterial infection model. We further describe that CIS-deficient mice displayed enhanced pro-inflammatory function and dramatically enhanced anti-bacterial immunity. Inhibition of CIS may present as a viable therapeutic option to enhance immunity towards bacterial infection.
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Infecções Bacterianas , Neoplasias , Animais , Imunidade Inata , Células Matadoras Naturais , Camundongos , Neoplasias/terapia , Fator de Crescimento Transformador beta/metabolismoRESUMO
Despite repeated malaria infection, individuals living in areas where malaria is endemic remain vulnerable to reinfection. The Janus kinase (JAK1/2) inhibitor ruxolitinib could potentially disrupt the parasite-induced dysfunctional immune response when administered with antimalarial therapy. This randomized, single-blind, placebo-controlled, single-center phase 1 trial investigated the safety, tolerability, and pharmacokinetic and pharmacodynamic profile of ruxolitinib and the approved antimalarial artemether-lumefantrine in combination. Ruxolitinib pharmacodynamics were assessed by inhibition of phosphorylation of signal transducer and activator of transcription 3 (pSTAT3). Eight healthy male and female participants ages 18 to 55 years were randomized to either ruxolitinib (20 mg) (n = 6) or placebo (n = 2) administered 2 h after artemether-lumefantrine (80/480 mg) twice daily for 3 days. Mild adverse events occurred in six participants (four ruxolitinib; two placebo). The combination of artemether-lumefantrine and ruxolitinib was well tolerated, with adverse events and pharmacokinetics consistent with the known profiles of both drugs. The incidence of adverse events and artemether, dihydroartemisinin (the major active metabolite of artemether), and lumefantrine exposure were not affected by ruxolitinib coadministration. Ruxolitinib coadministration resulted in a 3-fold-greater pSTAT3 inhibition compared to placebo (geometric mean ratio = 3.01 [90% confidence interval = 2.14 to 4.24]), with a direct and predictable relationship between ruxolitinib plasma concentrations and %pSTAT3 inhibition. This study supports the investigation of the combination of artemether-lumefantrine and ruxolitinib in healthy volunteers infected with Plasmodium falciparum malaria. (This study has been registered at ClinicalTrials.gov under registration no. NCT04456634.).
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Antimaláricos , Malária Falciparum , Adolescente , Adulto , Antimaláricos/efeitos adversos , Artemeter/uso terapêutico , Combinação Arteméter e Lumefantrina/uso terapêutico , Combinação de Medicamentos , Etanolaminas/uso terapêutico , Feminino , Fluorenos/uso terapêutico , Humanos , Lumefantrina/uso terapêutico , Malária Falciparum/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Nitrilas , Pirazóis , Pirimidinas , Método Simples-Cego , Adulto JovemRESUMO
Antibody-dependent enhancement (ADE) of viral disease has been demonstrated for infections caused by flaviviruses and influenza viruses; however, antibodies that enhance bacterial disease are relatively unknown. In recent years, a few studies have directly linked antibodies with exacerbation of bacterial disease. This ADE of bacterial disease has been observed in mouse models and human patients with bacterial infections. This antibody-mediated enhancement of bacterial infection is driven by various mechanisms that are disparate from those found in viral ADE. This review aims to highlight and discuss historic evidence, potential molecular mechanisms, and current therapies for ADE of bacterial infection. Based on specific case studies, we report how plasmapheresis has been successfully used in patients to ameliorate infection-related symptomatology associated with bacterial ADE. A greater understanding and appreciation of bacterial ADE of infection and disease could lead to better management of infections and inform current vaccine development efforts.
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Anticorpos Facilitadores/imunologia , Infecções Bacterianas/etiologia , Interações Hospedeiro-Patógeno/imunologia , Animais , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/imunologia , Aderência Bacteriana , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/terapia , Gerenciamento Clínico , Suscetibilidade a Doenças , Humanos , Imunidade Humoral , Fagocitose/imunologia , Prevalência , Proteólise , VirulênciaRESUMO
Pseudomonas aeruginosa is one of the principal pathogens implicated in respiratory infections of patients with cystic fibrosis (CF) and non-CF bronchiectasis. Previously, we demonstrated that impaired serum-mediated killing of P. aeruginosa was associated with increased severity of respiratory infections in patients with non-CF bronchiectasis. This inhibition was mediated by high titers of O-antigen-specific IgG2 antibodies that cloak the surface of the bacteria, blocking access to the membrane. Infection-related symptomatology was ameliorated in patients by using plasmapheresis to remove the offending antibodies. To determine if these inhibitory "cloaking antibodies" were prevalent in patients with CF, we investigated 70 serum samples from patients with P. aeruginosa infection and 5 from those without P. aeruginosa infection. Of these patients, 32% had serum that inhibited the ability of healthy control serum to kill P. aeruginosa. Here, we demonstrate that this inhibition of killing requires O-antigen expression. Furthermore, we reveal that while IgG alone can inhibit the activity of healthy control serum, O-antigen-specific IgA in patient sera can also inhibit serum-killing. We found that antibody affinity, not just titer, was also important in the inhibition of serum-mediated killing. These studies provide novel insight into cloaking antibodies in human infection and may provide further options in CF and other diseases for treatment of recalcitrant P. aeruginosa infections.
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Anticorpos Antibacterianos/imunologia , Fibrose Cística/complicações , Imunoglobulina A/imunologia , Imunoglobulina G/imunologia , Lipopolissacarídeos/imunologia , Infecções por Pseudomonas/etiologia , Pseudomonas aeruginosa/imunologia , Proteínas do Sistema Complemento/imunologia , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunoglobulina A/sangue , Imunoglobulina G/sangueRESUMO
OBJECTIVES: Analysis of oral dysbiosis in individuals sharing genetic and environmental risk factors with rheumatoid arthritis (RA) patients may illuminate how microbiota contribute to disease susceptibility. We studied the oral microbiota in a prospective cohort of patients with RA, first-degree relatives (FDR) and healthy controls (HC), then genomically and functionally characterised streptococcal species from each group to understand their potential contribution to RA development. METHODS: After DNA extraction from tongue swabs, targeted 16S rRNA gene sequencing and statistical analysis, we defined a microbial dysbiosis score based on an operational taxonomic unit signature of disease. After selective culture from swabs, we identified streptococci by sequencing. We examined the ability of streptococcal cell walls (SCW) from isolates to induce cytokines from splenocytes and arthritis in ZAP-70-mutant SKG mice. RESULTS: RA and FDR were more likely to have periodontitis symptoms. An oral microbial dysbiosis score discriminated RA and HC subjects and predicted similarity of FDR to RA. Streptococcaceae were major contributors to the score. We identified 10 out of 15 streptococcal isolates as S. parasalivarius sp. nov., a distinct sister species to S. salivarius. Tumour necrosis factor and interleukin 6 production in vitro differed in response to individual S. parasalivarius isolates, suggesting strain specific effects on innate immunity. Cytokine secretion was associated with the presence of proteins potentially involved in S. parasalivarius SCW synthesis. Systemic administration of SCW from RA and HC-associated S. parasalivarius strains induced similar chronic arthritis. CONCLUSIONS: Dysbiosis-associated periodontal inflammation and barrier dysfunction may permit arthritogenic insoluble pro-inflammatory pathogen-associated molecules, like SCW, to reach synovial tissue.
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Artrite Reumatoide/microbiologia , Biopolímeros/isolamento & purificação , Disbiose/microbiologia , Peptidoglicano/isolamento & purificação , Periodontite/microbiologia , Streptococcus/isolamento & purificação , Adulto , Animais , Suscetibilidade a Doenças/microbiologia , Feminino , Humanos , Masculino , Camundongos , Microbiota , Pessoa de Meia-Idade , Boca/microbiologia , Linhagem , RNA Ribossômico 16SRESUMO
BACKGROUND: For uncomplicated Plasmodium falciparum malaria, highly efficacious single-dose treatments are expected to increase compliance and improve treatment outcomes, and thereby may slow the development of resistance. The efficacy and safety of a single-dose combination of artefenomel (800 mg) plus ferroquine (400/600/900/1200 mg doses) for the treatment of uncomplicated P. falciparum malaria were evaluated in Africa (focusing on children ≤ 5 years) and Asia. METHODS: The study was a randomized, double-blind, single-dose, multi-arm clinical trial in patients aged > 6 months to < 70 years, from six African countries and Vietnam. Patients were followed up for 63 days to assess treatment efficacy, safety and pharmacokinetics. The primary efficacy endpoint was the polymerase chain reaction (PCR)-adjusted adequate clinical and parasitological response (ACPR) at Day 28 in the Per-Protocol [PP] Set comprising only African patients ≤ 5 years. The exposure-response relationship for PCR-adjusted ACPR at Day 28 and prevalence of kelch-13 mutations were explored. RESULTS: A total of 373 patients were treated: 289 African patients ≤ 5 years (77.5%), 64 African patients > 5 years and 20 Asian patients. None of the treatment arms met the target efficacy criterion for PCR-adjusted ACPR at Day 28 (lower limit of 95% confidence interval [CI] > 90%). PCR-adjusted ACPR at Day 28 [95% CI] in the PP Set ranged from 78.4% [64.7; 88.7%] to 91.7% [81.6; 97.2%] for the 400 mg to 1200 mg ferroquine dose. Efficacy rates were low in Vietnamese patients, ranging from 20 to 40%. A clear relationship was found between drug exposure (artefenomel and ferroquine concentrations at Day 7) and efficacy (primary endpoint), with higher concentrations of both drugs resulting in higher efficacy. Six distinct kelch-13 mutations were detected in parasite isolates from 10/272 African patients (with 2 mutations known to be associated with artemisinin resistance) and 18/20 Asian patients (all C580Y mutation). Vomiting within 6 h of initial artefenomel administration was common (24.6%) and associated with lower drug exposures. CONCLUSION: The efficacy of artefenomel/ferroquine combination was suboptimal in African children aged ≤ 5 years, the population of interest, and vomiting most likely had a negative impact on efficacy. Trial registration ClinicalTrials.gov, NCT02497612. Registered 14 Jul 2015, https://clinicaltrials.gov/ct2/show/NCT02497612?term=NCT02497612&draw=2&rank=1.
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Adamantano/análogos & derivados , Aminoquinolinas/administração & dosagem , Antimaláricos/administração & dosagem , Compostos Ferrosos/administração & dosagem , Malária Falciparum/prevenção & controle , Metalocenos/administração & dosagem , Peróxidos/administração & dosagem , Plasmodium falciparum/efeitos dos fármacos , Adamantano/administração & dosagem , Adolescente , Adulto , Idoso , Benin , Burkina Faso , Criança , Pré-Escolar , Método Duplo-Cego , Combinação de Medicamentos , Feminino , Gabão , Humanos , Lactente , Quênia , Masculino , Pessoa de Meia-Idade , Moçambique , Uganda , Vietnã , Adulto JovemRESUMO
Salmonella enterica serovar Typhimurium ST313 is a relatively newly emerged sequence type that is causing a devastating epidemic of bloodstream infections across sub-Saharan Africa. Analysis of hundreds of Salmonella genomes has revealed that ST313 is closely related to the ST19 group of S Typhimurium that cause gastroenteritis across the world. The core genomes of ST313 and ST19 vary by only â¼1,000 SNPs. We hypothesized that the phenotypic differences that distinguish African Salmonella from ST19 are caused by certain SNPs that directly modulate the transcription of virulence genes. Here we identified 3,597 transcriptional start sites of the ST313 strain D23580, and searched for a gene-expression signature linked to pathogenesis of Salmonella We identified a SNP in the promoter of the pgtE gene that caused high expression of the PgtE virulence factor in African S. Typhimurium, increased the degradation of the factor B component of human complement, contributed to serum resistance, and modulated virulence in the chicken infection model. We propose that high levels of PgtE expression by African S Typhimurium ST313 promote bacterial survival and dissemination during human infection. Our finding of a functional role for an extragenic SNP shows that approaches used to deduce the evolution of virulence in bacterial pathogens should include a focus on noncoding regions of the genome.
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Evolução Molecular , Genoma Bacteriano/genética , Infecções por Salmonella/microbiologia , Salmonella typhimurium/genética , Salmonella typhimurium/patogenicidade , DNA Bacteriano/genética , Epidemias , Humanos , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Virulência/genética , Fatores de Virulência/genéticaRESUMO
Collecting precise as-built data is essential for tracking construction progress. Three-dimensional models generated from such data capture the as-is conditions of the structures, providing valuable information for monitoring existing infrastructure over time. As-built data can be acquired using a wide range of remote sensing technologies, among which mobile LiDAR is gaining increasing attention due to its ability to collect high-resolution data over a relatively large area in a short time. The quality of mobile LiDAR data depends not only on the grade of onboard LiDAR scanners but also on the accuracy of direct georeferencing information and system calibration. Consequently, millimeter-level accuracy is difficult to achieve. In this study, the performance of mapping-grade and surveying-grade mobile LiDAR systems for bridge monitoring is evaluated against static laser scanners. Field surveys were conducted over a concrete bridge where grinding was required to achieve desired smoothness. A semi-automated, feature-based fine registration strategy is proposed to compensate for the impact of georeferencing and system calibration errors on mobile LiDAR data. Bridge deck thickness is evaluated using surface segments to minimize the impact of inherent noise in the point cloud. The results show that the two grades of mobile LiDAR delivered thickness estimates that are in agreement with those derived from static laser scanning in the 1 cm range. The mobile LiDAR data acquisition took roughly five minutes without having a significant impact on traffic, while the static laser scanning required more than three hours.
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BACKGROUND: The impact of temporal feeding patterns remains a major unanswered question in nutritional science. Progress has been hampered by the absence of a reliable method to impose temporal feeding in laboratory rodents, without the confounding influence of food-hoarding behavior. OBJECTIVE: The aim of this study was to develop and validate a reliable method for supplying crushed diets to laboratory rodents in consistent, relevant feeding patterns for prolonged periods. METHODS: We programmed our experimental feeding station to deliver a standard diet [StD; Atwater Fuel Energy (AFE) 13.9% fat] or high-fat diet (HFD; AFE 45% fat) during nocturnal grazing [providing 1/24th of the total daily food intake (tdF/I) of ad libitum-fed controls every 30 min] and meal-fed (3 × 1-h periods of ad libitum feeding) patterns in male rats (Sprague-Dawley: 4 wk old, 72-119 g) and mice [C57/Bl6J wild-type (WT): 6 mo old, 29-37 g], and ghrelin-null littermates (Ghr-/-; 27-34 g). RESULTS: Grazing yielded accurate, consistent feeding events in rats, with an approximately linear rise in nocturnal cumulative food intake [tdF/I (StD): 97.4 ± 1.5% accurate compared with manual measurement; R2 = 0.86; tdF/I (HFD): 99.0 ± 1.4% accurate; R2 = 0.86]. Meal-feeding produced 3 nocturnal meals of equal size and duration in StD-fed rats (tdF/I: 97.4 ± 0.9% accurate; R2 = 0.90), whereas the second meal size increased progressively in HFD-fed rats (44% higher on day 35 than on day 14; P < 0.01). Importantly, cumulative food intake in grazing and meal-fed rats was identical. Similar results were obtained in WT mice except that less restricted grazing induced hyperphagia (compared with meal-fed WT mice; P < 0.05 from day 1). This difference was abolished in Ghr-/- mice, with meal initiation delayed and meal duration enhanced. Neither pattern elevated corticosterone secretion in rats, but meal-feeding aligned ultradian pulses. CONCLUSIONS: We have established a consistent, measurable, researcher-defined, stress-free method for imposing temporal feeding patterns in rats and mice. This approach will facilitate progress in understanding the physiologic impact of feeding patterns.
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Comportamento Alimentar/fisiologia , Animais , Corticosterona/sangue , Dieta , Dieta Hiperlipídica , Ingestão de Alimentos , Grelina/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos Sprague-DawleyRESUMO
Progress made in malaria control during the past decade has prompted increasing global dialogue on malaria elimination and eradication. The product development pipeline for malaria has never been stronger, with promising new tools to detect, treat, and prevent malaria, including innovative diagnostics, medicines, vaccines, vector control products, and improved mechanisms for surveillance and response. There are at least 25 projects in the global malaria vaccine pipeline, as well as 47 medicines and 13 vector control products. In addition, there are several next-generation diagnostic tools and reference methods currently in development, with many expected to be introduced in the next decade. The development and adoption of these tools, bolstered by strategies that ensure rapid uptake in target populations, intensified mechanisms for information management, surveillance, and response, and continued financial and political commitment are all essential to achieving global eradication.
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Antimaláricos/uso terapêutico , Malária/prevenção & controle , Resistência Microbiana a Medicamentos , Monitoramento Epidemiológico , Humanos , Inseticidas , Malária/diagnóstico , Prática de Saúde PúblicaRESUMO
Over the last two decades there has been a renaissance in the pipeline of new drugs targeting malaria, with the launch of new products that help save the lives of children throughout the world. In addition, there is a wealth of new molecules both entering and progressing through clinical development. These bring hope for a new generation of simpler and more effective cures that could overcome the emerging threat of drug resistance. In addition, there is hope that some of these medicines will have prophylactic activity and can be used to protect vulnerable populations, given the absence of a highly effective vaccine. Switzerland has played a key role in the development of these medicines. First, the country has a long history of understanding the biology of parasites and the pharmacology of drug responses through the leadership of the Swiss Tropical and Public Health Institute in Basel. Second, the highly successful Swiss pharmaceutical industry brings, beyond excellence, a strong interest in neglected diseases, building on work at Hoffmann-La Roche in the last century and with more recent products from Novartis and other Swiss companies. Third, the emergence of product-development-partnerships, in this case led by the Medicines for Malaria Venture, based in Geneva, has helped to catalyze the development of new medicines and bring the community together within Switzerland and beyond. Finally, this progress would not have been possible without the engagement of the Swiss people and the support of the federal government through the Swiss Agency for Development and Cooperation (SDC), the State Secretariat of Education, Research and Innovation (SERI) and the Swiss Republic and Canton of Geneva.
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Antimaláricos/história , Indústria Farmacêutica/história , Cooperação Internacional/história , Malária/tratamento farmacológico , História do Século XX , História do Século XXI , Humanos , SuíçaRESUMO
The global fight against malaria requires continual development of new tools. Collaborations in India have played a key role in MMV's partnerships to discover, develop and deliver new medicines. Over the last decade, India has become a focal point of global medicinal chemistry, and combined with investments in basic science, this has led to the discovery of new potential drugs. India also brings significant experience to drug development, in clinical trials, but also in formulation and manufacturing. Finally, innovative new approaches in case management have streamlined impact at the level of communities and the patients.
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Controle de Doenças Transmissíveis/tendências , Malária/tratamento farmacológico , Malária/prevenção & controle , Antimaláricos/uso terapêutico , Controle de Doenças Transmissíveis/métodos , Descoberta de Drogas/estatística & dados numéricos , Descoberta de Drogas/tendências , Saúde Global , Humanos , Índia/epidemiologia , Vacinas AntimaláricasRESUMO
In the last 2 decades, renewed attention to neglected tropical diseases (NTDs) has spurred the development of antiparasitic agents, especially in light of emerging drug resistance. The need for new drugs has required in vitro screening methods using parasite culture. Furthermore, clinical laboratories sought to correlate in vitro susceptibility methods with treatment outcomes, most notably with malaria. Parasites with their various life cycles present greater complexity than bacteria, for which standardized susceptibility methods exist. This review catalogs the state-of-the-art methodologies used to evaluate the effects of drugs on key human parasites from the point of view of drug discovery as well as the need for laboratory methods that correlate with clinical outcomes.