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1.
Environ Sci Pollut Res Int ; 30(17): 50713-50722, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36797390

RESUMO

Lead-based ammunition (gunshot and bullets) frequently leaves small lead fragments embedded in the meat of wild-shot game animals. Australia produces several commercial game meat products from wild animals harvested with lead-based ammunition and has a growing population of recreational hunters. However, no studies have previously investigated the frequency of lead fragments or lead concentrations in Australian game meat. We examined 133 Australian minced game meat items of four types for evidence of lead contamination. Samples were meat from kangaroos (Macropus and Osphranter spp.; n=36) and Bennett's wallabies (Notamacropus rufogriseus; n=28) sold for human consumption, and deer ('venison'; multiple spp.; n=32) and stubble quail (Coturnix pectoralis; n=37) harvested for private consumption by recreational hunters. All packages were studied by digital radiography to detect the presence of radio-dense fragments, assumed to be lead fragments from ammunition. Visible fragments were absent in commercially available kangaroo products, but were present in 4%, 28% and 35% of wallaby, venison and quail, respectively. Mean meat lead concentrations (mg/kg wet weight) were 0.01 ± 0.01 for kangaroo, 0.02 ± 0.01 for wallaby, 0.12 ± 0.07 for venison, and 1.76 ± 3.76 for quail. The Australian food standards threshold for livestock meat (0.1 mg/kg w.w.) was not exceeded by any kangaroo or wallaby products but was exceeded by 53% and 86% of venison and quail, respectively. Radiography only detected 35% of samples that were above the food safety threshold. While average lead concentrations in commercially available macropod (kangaroo and wallaby) meat were low, those in recreationally harvested game meat may pose health risks for hunters and associated consumers.


Assuntos
Cervos , Intoxicação por Chumbo , Humanos , Animais , Chumbo/análise , Macropodidae , Coturnix , Contaminação de Alimentos/análise , Austrália , Carne/análise , Animais Selvagens , Codorniz
3.
Pharmacol Res ; 177: 106076, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35074524

RESUMO

Drug discovery from natural sources is going through a renaissance, having spent many decades in the shadow of synthetic molecule drug discovery, despite the fact that natural product-derived compounds occupy a much greater chemical space than those created through synthetic chemistry methods. With this new era comes new possibilities, not least the novel targets that have emerged in recent times and the development of state-of-the-art technologies that can be applied to drug discovery from natural sources. Although progress has been made with some immunomodulating drugs, there remains a pressing need for new agents that can be used to treat the wide variety of conditions that arise from disruption, or over-activation, of the immune system; natural products may therefore be key in filling this gap. Recognising that, at present, there is no authoritative article that details the current state-of-the-art of the immunomodulatory activity of natural products, this in-depth review has arisen from a joint effort between the International Union of Basic and Clinical Pharmacology (IUPHAR) Natural Products and Immunopharmacology Sections, with contributions from a number of world-leading researchers in the field of natural product drug discovery, to provide a "position statement" on what natural products has to offer in the search for new immunomodulatory argents. To this end, we provide a historical look at previous discoveries of naturally occurring immunomodulators, present a picture of the current status of the field and provide insight into the future opportunities and challenges for the discovery of new drugs to treat immune-related diseases.


Assuntos
Produtos Biológicos , Farmacologia Clínica , Produtos Biológicos/química , Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Descoberta de Drogas , Fatores Imunológicos/farmacologia , Fatores Imunológicos/uso terapêutico , Agentes de Imunomodulação
7.
Am J Med ; 131(5): e181-e184, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29247605

RESUMO

BACKGROUND: The purpose of this article is to determine if conversion from eating wild game harvested with lead-based ammunition to nonlead-based ammunition results in lower blood lead levels. Supersonic injection of toxin-leeching frangible projectiles into food is intuitively bad. As much as 95% of the ~13.7 million hunters in the United States choose shrapnel-inducing lead bullets to kill game; in addition, not harvesting meat is an incarcerable crime. A lead ammunition ban on certain federal lands was recently rescinded and the National Rifle Association refutes any risk from eating lead bullet-harvested game. METHODS: A patient subsisting solely on lead-shot meat was converted to non-lead ammunition and his blood lead level tracked. Concomitant with his conversion to nonlead ammunition, a controlled experiment was performed using the patient's bullets to determine his daily lead intake from lead-shot meat. RESULTS: While eating lead-shot meat, the patient was consuming 259.3 ± 235.6 µg of lead daily and his blood lead level was 74.7 µg/dL. Conversion to nonlead ammunition was associated with a reduced blood lead level. CONCLUSIONS: Unsafe blood lead levels can occur from eating game harvested with lead ammunition. Physicians should warn hunting patients of this potential risk and counsel them about the availability of nonlead ammunition alternatives.


Assuntos
Intoxicação por Chumbo/diagnóstico , Chumbo/análise , Carne/análise , Animais , Doença Crônica , Cervos , Dieta Rica em Proteínas e Pobre em Carboidratos , Cabras , Humanos , Masculino , Pessoa de Meia-Idade
8.
Annu Rev Pharmacol Toxicol ; 58: 509-530, 2018 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-29077533

RESUMO

Descriptions of the use of natural products in traditional medicine have served as starting points for new therapeutics. The details of the traditional use of these organisms can provide important information for future drug discovery and development efforts. Recent technologic advances provide the framework to leverage ethnopharmacologic data in the drug discovery process. Information on the traditional harvest, preparation, storage, and administration of the organisms, and the natural products they contain, provides valuable details regarding characteristics of the active compounds. Importantly, researchers can now rapidly analyze and identify the multiple, and often synergistic, compounds contained in these natural products. Although we are entering the acme of ethnopharmacology, where information regarding the traditional use of organisms can provide valuable natural product leads and accelerate the identification of new therapeutics, this ethnopharmacologic resource is threatened by the loss of traditional medicine knowledge and extinction of organisms.


Assuntos
Produtos Biológicos/farmacologia , Produtos Biológicos/uso terapêutico , Animais , Bioprospecção/métodos , Descoberta de Drogas/métodos , Humanos , Medicina Tradicional/métodos
9.
JRSM Open ; 8(5): 2054270417694292, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28515952

RESUMO

We report a patient with a reduction in blood pressure through cessation of high-stress employment.

12.
Contemp Clin Trials Commun ; 5: 137-143, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29740629

RESUMO

There is no safe level of lead exposure. Correlations suggest that hunters harvesting wild game with lead bullets may be at risk of lead exposure through eating minute lead particles from shrapnel in their wild game. This feasibility study will determine if it is possible to conduct an interventional controlled, blinded study to evaluate if there is a causal relationship between meat harvested with lead bullets and elevated blood lead levels in those who consume the meat. This is an observational case crossover study and the primary outcome is blood lead levels. Individuals will have blood lead levels measured 2-4 days after eating one serving of meat harvested with lead bullets. At three potential washout periods these same individuals will have a subsequent blood lead level analysis. This observational study will provide the data necessary to determine the washout period and sample size for a prospective interventional study to evaluate if meat harvested with lead bullets raises blood-lead levels in those who consume the meat. This study has been approved by the Health and Disabilities Ethics Committees of New Zealand. TRIAL REGISTRATION: NCT02775890.

13.
N Z Med J ; 129(1440): 108-13, 2016 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-27538044

RESUMO

Zika virus infection has raised considerable concern in New Zealand, but the risks faced by most New Zealanders, while real, are quite small as New Zealand does not harbor the primary mosquito vector. Furthermore, in individuals with a competent immune system, the acute illness caused by Zika virus infection is generally mild. Serious complication associated with Zika virus infections include microcephaly and Guillain-Barré Syndrome. Pacific Island countries have reported cases of Zika virus infection and these climates support the mosquito vector. Thus, travelers to these areas are at risk of infection. New Zealand travelers returning from endemic areas have developed the illness associated with the virus, but the probability of autochthonous transmission in New Zealand is very small.


Assuntos
Síndrome de Guillain-Barré/epidemiologia , Microcefalia/epidemiologia , Viagem , Infecção por Zika virus/complicações , Infecção por Zika virus/epidemiologia , Surtos de Doenças , Feminino , Síndrome de Guillain-Barré/virologia , Humanos , Microcefalia/virologia , Nova Zelândia/epidemiologia , Guias de Prática Clínica como Assunto , Gravidez , Fatores de Risco , Zika virus , Infecção por Zika virus/transmissão
14.
Sci Rep ; 6: 28699, 2016 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-27345730

RESUMO

Neurologic complications associated with viral encephalitis, including seizures and cognitive impairment, are a global health issue, especially in children. We previously showed that hippocampal injury during acute picornavirus infection in mice is associated with calpain activation and is the result of neuronal death triggered by brain-infiltrating inflammatory monocytes. We therefore hypothesized that treatment with a calpain inhibitor would protect neurons from immune-mediated bystander injury. C57BL/6J mice infected with the Daniel's strain of Theiler's murine encephalomyelitis virus were treated with the FDA-approved drug ritonavir using a dosing regimen that resulted in plasma concentrations within the therapeutic range for calpain inhibition. Ritonavir treatment significantly reduced calpain activity in the hippocampus, protected hippocampal neurons from death, preserved cognitive performance, and suppressed seizure escalation, even when therapy was initiated 36 hours after disease onset. Calpain inhibition by ritonavir may be a powerful tool for preserving neurons and cognitive function and preventing neural circuit dysregulation in humans with neuroinflammatory disorders.


Assuntos
Calpaína/antagonistas & inibidores , Infecções por Cardiovirus/tratamento farmacológico , Inibidores de Cisteína Proteinase/farmacologia , Fármacos Neuroprotetores/farmacologia , Ritonavir/farmacologia , Theilovirus/metabolismo , Doença Aguda , Animais , Calpaína/metabolismo , Infecções por Cardiovirus/metabolismo , Infecções por Cardiovirus/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Hipocampo/virologia , Camundongos
15.
Environ Sci Pollut Res Int ; 23(15): 15773, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27272923
19.
Sci Rep ; 2: 545, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22848791

RESUMO

Neuronal injury during acute viral infection of the brain is associated with the development of persistent cognitive deficits and seizures in humans. In C57BL/6 mice acutely infected with the Theiler's murine encephalomyelitis virus, hippocampal CA1 neurons are injured by a rapid innate immune response, resulting in profound memory deficits. In contrast, infected SJL and B6xSJL F1 hybrid mice exhibit essentially complete hippocampal and memory preservation. Analysis of brain-infiltrating leukocytes revealed that SJL mice mount a sharply attenuated inflammatory monocyte response as compared to B6 mice. Bone marrow transplantation experiments isolated the attenuation to the SJL immune system. Adoptive transfer of B6 inflammatory monocytes into acutely infected B6xSJL hosts converted these mice to a hippocampal damage phenotype and induced a cognitive deficit marked by failure to recognize a novel object. These findings show that inflammatory monocytes are the critical cellular mediator of hippocampal injury during acute picornavirus infection of the brain.


Assuntos
Hipocampo/imunologia , Hipocampo/virologia , Monócitos/imunologia , Poliomielite/imunologia , Poliomielite/virologia , Theilovirus/fisiologia , Transferência Adotiva , Animais , Apoptose , Transplante de Medula Óssea , Transtornos Cognitivos/etiologia , Modelos Animais de Doenças , Feminino , Hipocampo/patologia , Imunofenotipagem , Masculino , Camundongos , Monócitos/citologia , Monócitos/metabolismo , Neurônios/patologia , Poliomielite/patologia , Tropismo Viral , Replicação Viral
20.
Am J Pathol ; 175(2): 668-84, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19608874

RESUMO

Many viruses, including picornaviruses, have the potential to infect the central nervous system (CNS) and stimulate a neuroinflammatory immune response, especially in infants and young children. Cognitive deficits associated with CNS picornavirus infection result from injury and death of neurons that may occur due to direct viral infection or during the immune responses to virus in the brain. Previous studies have concluded that apoptosis of hippocampal neurons during picornavirus infection is a cell-autonomous event triggered by direct neuronal infection. However, these studies assessed neuron death at time points late in infection and during infections that lead to either death of the host or persistent viral infection. In contrast, many neurovirulent picornavirus infections are acute and transient, with rapid clearance of virus from the host. We provide evidence of hippocampal pathology in mice acutely infected with the Theiler's murine encephalomyelitis picornavirus. We found that CA1 pyramidal neurons exhibited several hallmarks of apoptotic death, including caspase-3 activation, DNA fragmentation, and chromatin condensation within 72 hours of infection. Critically, we also found that many of the CA1 pyramidal neurons undergoing apoptosis were not infected with virus, indicating that neuronal cell death during acute picornavirus infection of the CNS occurs in a non-cell-autonomous manner. These observations suggest that therapeutic strategies other than antiviral interventions may be useful for neuroprotection during acute CNS picornavirus infection.


Assuntos
Apoptose , Hipocampo/patologia , Infecções por Picornaviridae/patologia , Células Piramidais/patologia , Theilovirus , Animais , Modelos Animais de Doenças , Hipocampo/virologia , Imageamento por Ressonância Magnética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células Piramidais/virologia
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