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1.
Malar J ; 23(1): 37, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38291392

RESUMO

BACKGROUND: A major challenge to malaria elimination is identifying and targeting populations that are harbouring residual infections and contributing to persistent transmission. In many near-elimination settings in Southeast Asia, it is known that forest-goers are at higher risk for malaria infection, but detailed information on their behaviours and exposures is not available. METHODS: In Aceh Province, Indonesia, a near-elimination setting where a growing proportion of malaria is due to Plasmodium knowlesi, a case-control study was conducted to identify risk factors for symptomatic malaria, characteristics of forest-goers, and key intervention points. From April 2017 to September 2018, cases and controls were recruited and enrolled in a 1:3 ratio. Cases had confirmed malaria infection by rapid diagnostic test or microscopy detected at a health facility (HF). Gender-matched controls were recruited from passive case detection among individuals with suspected malaria who tested negative at a health facility (HF controls), and community-matched controls were recruited among those testing negative during active case detection. Multivariable logistic regression (unconditional for HF controls and conditional for community controls) was used to identify risk factors for symptomatic malaria infection. RESULTS: There were 45 cases, of which 27 were P. knowlesi, 17 were Plasmodium vivax, and one was not determined. For controls, 509 and 599 participants were recruited from health facilities and the community, respectively. Forest exposures were associated with high odds of malaria; in particular, working and sleeping in the forest (HF controls: adjusted odds ratio (aOR) 21.66, 95% CI 5.09-92.26; community controls: aOR 16.78, 95% CI 2.19-128.7) and having a second residence in the forest (aOR 6.29, 95% CI 2.29-17.31 and 13.53, 95% CI 2.10-87.12). Male forest-goers were a diverse population employed in a variety of occupations including logging, farming, and mining, sleeping in settings, such as huts, tents, and barracks, and working in a wide range of group sizes. Reported use of protective measures, such as nets, hammock nets, mosquito coils, and repellents was low among forest-goers and interventions at forest residences were absent. CONCLUSIONS: Second residences in the forest and gaps in use of protective measures point to key malaria interventions to improve coverage in forest-going populations at risk for P. knowlesi and P. vivax in Aceh, Indonesia. Intensified strategies tailored to specific sub-populations will be essential to achieve elimination.


Assuntos
Malária Vivax , Malária , Masculino , Humanos , Indonésia/epidemiologia , Estudos de Casos e Controles , Malária/prevenção & controle , Malária Vivax/epidemiologia , Malária Vivax/prevenção & controle , Florestas
2.
J Neuroinflammation ; 20(1): 108, 2023 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-37149645

RESUMO

BACKGROUND: Frontotemporal dementia (FTD) is a heterogeneous group of early onset and progressive neurodegenerative disorders, characterized by degeneration in the frontal and temporal lobes, which causes deterioration in cognition, personality, social behavior and language. Around 45% of the cases are characterized by the presence of aggregates of the RNA-binding protein TDP-43. METHODS: In this study, we have used a murine model of FTD that overexpresses this protein exclusively in the forebrain (under the control of the CaMKIIα promoter) for several biochemical, histological and pharmacological studies focused on the endocannabinoid system. RESULTS: These mice exhibited at postnatal day 90 (PND90) important cognitive deficits, signs of emotional impairment and disinhibited social behaviour, which were, in most of cases, maintained during the first year of life of these animals. Motor activity was apparently normal, but FTD mice exhibited higher mortality. Their MRI imaging analysis and their ex-vivo histopathological evaluation proved changes compatible with atrophy (loss of specific groups of pyramidal neurons: Ctip2- and NeuN-positive cells) and inflammatory events (astroglial and microglial reactivities) in both cortical (medial prefrontal cortex) and subcortical (hippocampus) structures at PND90 and also at PND365. The analysis of the endocannabinoid system in these mice proved a decrease in the hydrolysing enzyme FAAH in the prefrontal cortex and the hippocampus, with an increase in the synthesizing enzyme NAPE-PLD only in the hippocampus, responses that were accompanied by modest elevations in anandamide and related N-acylethanolamines. The potentiation of these elevated levels of anandamide after the pharmacological inactivation of FAAH with URB597 resulted in a general improvement in behaviour, in particular in cognitive deterioration, associated with the preservation of pyramidal neurons of the medial prefrontal cortex and the CA1 layer of the hippocampus, and with the reduction of gliosis in both structures. CONCLUSIONS: Our data confirmed the potential of elevating the endocannabinoid tone as a therapy against TDP-43-induced neuropathology in FTD, limiting glial reactivity, preserving neuronal integrity and improving cognitive, emotional and social deficits.


Assuntos
Demência Frontotemporal , Doença de Pick , Masculino , Camundongos , Animais , Demência Frontotemporal/genética , Endocanabinoides/uso terapêutico , Camundongos Transgênicos , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo
3.
Int J Mol Sci ; 22(22)2021 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-34830414

RESUMO

In the present study, we investigated the involvement of the chaperone protein BiP (also known as GRP78 or Hspa5), a master regulator of intracellular proteostasis, in two mouse models of neurodegenerative diseases: amyotrophic lateral sclerosis (ALS) and Parkinson's disease (PD). To this end, we used mice bearing partial genetic deletion of the BiP gene (BiP+/- mice), which, for the ALS model, were crossed with mutant SOD1 (mSOD1) transgenic mice to generate mSOD1/BiP+/- double mutant mice. Our data revealed a more intense neurological decline in the double mutants, reflected in a greater deterioration of the neurological score and rotarod performance, with also a reduced animal survival, compared to mSOD1 transgenic mice. Such worsening was associated with higher microglial (labelled with Iba-1 immunostaining) and, to a lesser extent, astroglial (labelled with GFAP immunostaining) immunoreactivities found in the double mutants, but not with a higher loss of spinal motor neurons (labelled with Nissl staining) in the spinal cord. The morphological analysis of Iba-1 and GFAP-positive cells revealed a higher presence of activated cells, characterized by elevated cell body size and shorter processes, in double mutants compared to mSOD1 mice with normal BiP expression. In the case of the PD model, BiP+/- mice were unilaterally lesioned with the parkinsonian neurotoxin 6-hydroxydopamine (6-OHDA). In this case, however, we did not detect a greater susceptibility to damage in mutant mice, as the motor defects caused by 6-OHDA in the pole test and the cylinder rearing test, as well as the losses in tyrosine hydroxylase-containing neurons and the elevated glial reactivity (labelled with CD68 and GFAP immunostaining) detected in the substantia nigra were of similar magnitude in BiP+/- mice compared with wildtype animals. Therefore, our findings support the view that a dysregulation of the protein BiP may contribute to ALS pathogenesis. As BiP has been recently related to cannabinoid type-1 (CB1) receptor function, our work also opens the door to future studies on a possible link between BiP and the neuroprotective effects of cannabinoids that have been widely reported in this neuropathological context. In support of this possibility, preliminary data indicate that CB1 receptor levels are significantly reduced in mSOD1 mice having partial deletion of BiP gene.


Assuntos
Esclerose Lateral Amiotrófica/genética , Chaperona BiP do Retículo Endoplasmático/genética , Doença de Parkinson/genética , Receptor CB1 de Canabinoide/genética , Superóxido Dismutase-1/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Transgênicos/genética , Microglia/metabolismo , Microglia/patologia , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Oxidopamina/farmacologia , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Substância Negra/metabolismo , Substância Negra/patologia
4.
Molecules ; 26(24)2021 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-34946726

RESUMO

Cannabinoids act as pleiotropic compounds exerting, among others, a broad-spectrum of neuroprotective effects. These effects have been investigated in the last years in different preclinical models of neurodegeneration, with the cannabinoid type-1 (CB1) and type-2 (CB2) receptors concentrating an important part of this research. However, the issue has also been extended to additional targets that are also active for cannabinoids, such as the orphan G-protein receptor 55 (GPR55). In the present study, we investigated the neuroprotective potential of VCE-006.1, a chromenopyrazole derivative with biased orthosteric and positive allosteric modulator activity at GPR55, in murine models of two neurodegenerative diseases. First, we proved that VCE-006.1 alone could induce ERK1/2 activation and calcium mobilization, as well as increase cAMP response but only in the presence of lysophosphatidyl inositol. Next, we investigated this compound administered chronically in two neurotoxin-based models of Parkinson's disease (PD), as well as in some cell-based models. VCE-006.1 was active in reversing the motor defects caused by 6-hydroxydopamine (6-OHDA) in the pole and the cylinder rearing tests, as well as the losses in tyrosine hydroxylase-containing neurons and the elevated glial reactivity detected in the substantia nigra. Similar cytoprotective effects were found in vitro in SH-SY5Y cells exposed to 6-OHDA. We also investigated VCE-006.1 in LPS-lesioned mice with similar beneficial effects, except against glial reactivity and associated inflammatory events, which remained unaltered, a fact confirmed in BV2 cells treated with LPS and VCE-006.1. We also analyzed GPR55 in these in vivo models with no changes in its gene expression, although GPR55 was down-regulated in BV2 cells treated with LPS, which may explain the lack of efficacy of VCE-006.1 in such an assay. Furthermore, we investigated VCE-006.1 in two genetic models of amyotrophic lateral sclerosis (ALS), mutant SOD1, or TDP-43 transgenic mice. Neither the neurological decline nor the deteriorated rotarod performance were prevented with this compound, and the same happened with the elevated microglial and astroglial reactivities, albeit modest spinal motor neuron preservation was achieved in both models. We also analyzed GPR55 in these in vivo models and found no changes in both TDP-43 transgenic and mSOD1 mice. Therefore, our findings support the view that targeting the GPR55 may afford neuroprotection in experimental PD, but not in ALS, thus stressing the specificities for the development of cannabinoid-based therapies in the different neurodegenerative disorders.


Assuntos
Esclerose Lateral Amiotrófica , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson , Receptores de Canabinoides/metabolismo , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Animais , Modelos Animais de Doenças , Humanos , Ligantes , Masculino , Camundongos , Camundongos Transgênicos , Neuroglia/metabolismo , Fármacos Neuroprotetores/química , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Substância Negra/metabolismo , Células U937
5.
Malar J ; 19(1): 441, 2020 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-33256743

RESUMO

BACKGROUND: Following a dramatic decline of malaria cases in Aceh province, geographically-based reactive case detection (RACD) was recently evaluated as a tool to improve surveillance with the goal of malaria elimination. While RACD detected few cases in households surrounding index cases, engaging in forest work was identified as a risk factor for malaria and infections from Plasmodium knowlesi-a non-human primate malaria parasite-were more common than expected. This qualitative formative assessment was conducted to improve understanding of malaria risk from forest work and identify strategies for targeted surveillance among forest workers, including adapting reactive case detection. METHODS: Between June and August, 2016, five focus groups and 18 in-depth interviews with forest workers and key informants were conducted in each of four subdistricts in Aceh Besar and Aceh Jaya districts. Themes included: types of forest activities, mobility of workers, interactions with non-human primates, malaria prevention and treatment-seeking behaviours, and willingness to participate in malaria surveys at forest work sites and using peer-referral. RESULTS: Reported forest activities included mining, logging, and agriculture in the deep forest and along the forest fringe. Forest workers, particularly miners and loggers, described often spending weeks to months at work sites in makeshift housing, rarely utilizing mosquito prevention and, upon fever, self-medicating and seeking care from traditional healers or pharmacies rather than health facilities. Non-human primates are frequently observed near work sites, and most forest work locations are within a day's journey of health clinics. Employers and workers expressed interest in undertaking malaria testing and in participating in survey recruitment by peer-referral and at work sites. CONCLUSIONS: Diverse groups of forest workers in Aceh are potentially exposed to malaria through forest work. Passive surveillance and household-based screening may under-estimate malaria burden due to extended stays in the forest and health-seeking behaviours. Adapting active surveillance to specifically target forest workers through work-site screening and/or peer-referral appears promising for addressing currently undetected infections.


Assuntos
Agricultura Florestal , Malária/epidemiologia , Doenças Profissionais/epidemiologia , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Plasmodium knowlesi/isolamento & purificação , Adulto , Feminino , Humanos , Incidência , Indonésia/epidemiologia , Malária/parasitologia , Malária/psicologia , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/parasitologia , Doenças Profissionais/psicologia , Plasmodium/isolamento & purificação , Fatores de Risco , Adulto Jovem
6.
Malar J ; 18(1): 179, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31118028

RESUMO

BACKGROUND: Identifying efficient and effective strategies to reach and monitor populations at greatest risk of malaria in low-transmission settings is a key challenge for malaria elimination. In Namibia's Zambezi Region, transmission is ongoing yet its drivers remain poorly understood. A growing literature suggests that night-time social activities may lead to malaria exposure that is beyond the reach of conventional preventive interventions, such as insecticide treated bed nets and indoor residual spraying. METHODS: Formative research was conducted with community members in March, 2015 in the catchment areas of six randomly selected health facilities in the western Zambezi Region to identify night-time locations where large numbers of individuals regularly congregate. Using time-location sampling, a survey was conducted between March and May, 2015 at community-identified venues (bars and evening church services) to develop representative estimates of the prevalence of parasite infection and risk factors among venue-goers. RESULTS: When compared to a contemporaneous household survey of the general population aged 15 and older (N = 1160), venue-goers (N = 480) were more likely to have spent the night away from their home recently (17.3% vs. 8.9%, P = 0.008), report recent fever (65.2% vs. 36.9%, P < 0.001), and were less likely to have sought care for fever (37.9% vs. 52.1%, P = 0.011). Venue-goers had higher, but not significantly different, rates of malaria infection (4.7% vs. 2.8%, P = 0.740). Risk factors for malaria infection among venue-goers could not be determined due to the small number of infections identified, however self-reported fever was positively associated with outdoor livelihood activities (adjusted odds ratio [AOR] = 1.9, 95% CI 1.0-3.3), not wearing protective measures at the time of the survey (AOR = 6.8, 9% CI 1.4-33.6) and having been bothered by mosquitos at the venue (AOR = 2.7, 95% CI 1.5-4). CONCLUSIONS: Prevention measures and continued surveillance at night-time venues may be a useful complement to existing malaria elimination efforts.


Assuntos
Escuridão , Malária/transmissão , Controle de Mosquitos/métodos , Adolescente , Adulto , Animais , Anopheles/parasitologia , Feminino , Humanos , Mosquiteiros Tratados com Inseticida/estatística & dados numéricos , Atividades de Lazer , Malária/prevenção & controle , Masculino , Pessoa de Meia-Idade , Namíbia/epidemiologia , Prevalência , Medição de Risco , Fatores de Risco , Estudos de Amostragem , Inquéritos e Questionários , Adulto Jovem
7.
Malar J ; 18(1): 408, 2019 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-31806025

RESUMO

BACKGROUND: Haiti and the Dominican Republic (DR) are targeting malaria elimination by 2022. The private health sector has been relatively unengaged in these efforts, even though most primary health care in Haiti is provided by non-state actors, and many people use traditional medicine. Data on private health sector participation in malaria elimination efforts are lacking, as are data on care-seeking behaviour of patients in the private health sector. This study sought to describe the role of private health sector providers, care-seeking behaviour of individuals at high risk of malaria, and possible means of engaging the private health sector in Hispaniola's malaria elimination efforts. METHODS: In-depth interviews with 26 key informants (e.g. government officials), 62 private providers, and 63 patients of private providers, as well as 12 focus group discussions (FGDs) with community members, were conducted within seven study sites in Haiti and the DR. FGDs focused on local definitions of the private health sector and identified private providers for interview recruitment, while interviews focused on private health sector participation in malaria elimination activities and treatment-seeking behaviour of febrile individuals. RESULTS: Interviews revealed that self-medication is the most common first step in the trajectory of care for fevers in both Haiti and the DR. Traditional medicine is more commonly used in Haiti than in the DR, with many patients seeking care from traditional healers before, during, and/or after care in the formal health sector. Private providers were interested in participating in malaria elimination efforts but emphasized the need for ongoing support and training. Key informants agreed that the private health sector needs to be engaged, especially traditional healers in Haiti. The Haitian migrant population was reported to be one of the most at-risk groups by participants from both countries. CONCLUSION: Malaria elimination efforts across Hispaniola could be enhanced by engaging traditional healers in Haiti and other private providers with ongoing support and trainings; directing educational messaging to encourage proper treatment-seeking behaviour; and refining cross-border strategies for surveillance of the high-risk migrant population. Increasing distribution of rapid diagnostic tests (RDTs) and bi-therapy to select private health sector facilities, accompanied by adopting regulatory policies, could help increase numbers of reported and correctly treated malaria cases.


Assuntos
Erradicação de Doenças/estatística & dados numéricos , Malária Falciparum/prevenção & controle , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Vigilância da População , Setor Privado/estatística & dados numéricos , Adulto , Idoso , República Dominicana , Feminino , Grupos Focais , Haiti , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Adulto Jovem
8.
Malar J ; 16(1): 33, 2017 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-28100237

RESUMO

To eliminate malaria, malaria programmes need to develop new strategies for surveillance and response appropriate for the changing epidemiology that accompanies transmission decline, in which transmission is increasingly driven by population subgroups whose behaviours place them at increased exposure. Conventional tools of malaria surveillance and response are likely not sufficient in many elimination settings for accessing high-risk population subgroups, such as mobile and migrant populations (MMPs), given their greater likelihood of asymptomatic infections, illegal risk behaviours, limited access to public health facilities, and high mobility including extended periods travelling away from home. More adaptive, targeted strategies are needed to monitor transmission and intervention coverage effectively in these groups. Much can be learned from HIV programmes' experience with "second generation surveillance", including how to rapidly adapt surveillance and response strategies to changing transmission patterns, biological and behavioural surveys that utilize targeted sampling methods for specific behavioural subgroups, and methods for population size estimation. This paper reviews the strategies employed effectively for HIV programmes and offers considerations and recommendations for adapting them to the malaria elimination context.


Assuntos
Antimaláricos/administração & dosagem , Monitoramento Epidemiológico , Malária/diagnóstico , Malária/tratamento farmacológico , Transmissão de Doença Infecciosa/prevenção & controle , Infecções por HIV/diagnóstico , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Humanos , Malária/prevenção & controle , Controle de Mosquitos/métodos
9.
Pathobiology ; 81(3): 149-59, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24642775

RESUMO

OBJECTIVES: Spinocerebellar ataxias (SCAs) are characterized by a loss of balance and motor coordination due to degeneration of the cerebellum and its afferent and efferent connections. We recently found important changes in cannabinoid CB1 and CB2 receptors in the post-mortem cerebellum of patients affected by different SCAs. METHODS: We wanted to further explore this issue by analysing the two major endocannabinoid-hydrolysing enzymes, fatty acid amide hydrolase (FAAH) and monoacyl glycerol lipase (MAGL), in the post-mortem cerebellum of SCA patients and control subjects. RESULTS: Immunoreactivity for the FAAH and MAGL enzymes was found in the granular layer, in Purkinje cells, in neurons of the dentate nucleus and in areas of white matter in the cerebellum of patients at levels frequently notably higher than those in control subjects. Using double-labelling procedures, we found co-localization of FAAH and MAGL with calbindin, supporting the presence of these enzymes in Purkinje neurons. CONCLUSIONS: Degradative endocannabinoid enzymes are significantly increased in the cerebellum of SCA patients, which would presumably lead to reduced endocannabinoid levels. The identification of these enzymes in Purkinje neurons suggests a relationship with the pathogenesis of SCAs and suggests that the endocannabinoid system could provide potential therapeutic targets for the treatment of disease progression in SCAs.


Assuntos
Amidoidrolases/metabolismo , Cerebelo/metabolismo , Endocanabinoides/metabolismo , Monoacilglicerol Lipases/metabolismo , Ataxias Espinocerebelares/metabolismo , Idoso , Idoso de 80 Anos ou mais , Autopsia , Estudos de Casos e Controles , Núcleos Cerebelares/metabolismo , Núcleos Cerebelares/patologia , Cerebelo/patologia , Feminino , Humanos , Hidrólise , Masculino , Pessoa de Meia-Idade , Células de Purkinje/metabolismo , Células de Purkinje/patologia , Receptor CB1 de Canabinoide/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Ataxias Espinocerebelares/patologia , Substância Branca/metabolismo , Substância Branca/patologia
10.
Biomed Pharmacother ; 174: 116473, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522237

RESUMO

BACKGROUND: The elevation of endocannabinoid levels through inhibiting their degradation afforded neuroprotection in CaMKIIα-TDP-43 mice, a conditional transgenic model of frontotemporal dementia. However, which cannabinoid receptors are mediating these benefits is still pending to be elucidated. METHODS: We have investigated the involvement of the CB1 and the CB2 receptor using chronic treatments with selective ligands in CaMKIIα-TDP-43 mice, analysis of their cognitive deterioration with the Novel Object Recognition test, and immunostaining for neuronal and glial markers in two areas of interest in frontotemporal dementia. RESULTS: Our results confirmed the therapeutic value of activating either the CB1 or the CB2 receptor, with improvements in the animal performance in the Novel Object Recognition test, preservation of pyramidal neurons, in particular in the medial prefrontal cortex, and attenuation of glial reactivity, in particular in the hippocampus. In addition, the activation of both CB1 and CB2 receptors reduced the elevated levels of TDP-43 in the medial prefrontal cortex of CaMKIIα-TDP-43 mice, an effect exerted by mechanisms that are currently under investigation. CONCLUSIONS: These data reinforce the notion that the activation of CB1 and CB2 receptors may represent a promising therapy against TDP-43-induced neuropathology in frontotemporal dementia. Future studies will have to confirm these benefits, in particular with one of the selective CB2 agonists used here, which has been thoroughly characterized for clinical development.


Assuntos
Canabinoides , Modelos Animais de Doenças , Demência Frontotemporal , Camundongos Transgênicos , Fármacos Neuroprotetores , Receptor CB1 de Canabinoide , Receptor CB2 de Canabinoide , Animais , Receptor CB2 de Canabinoide/agonistas , Receptor CB2 de Canabinoide/metabolismo , Masculino , Fármacos Neuroprotetores/farmacologia , Receptor CB1 de Canabinoide/metabolismo , Receptor CB1 de Canabinoide/agonistas , Demência Frontotemporal/tratamento farmacológico , Demência Frontotemporal/metabolismo , Demência Frontotemporal/patologia , Camundongos , Canabinoides/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Córtex Pré-Frontal/patologia , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteínas de Ligação a DNA/metabolismo , Camundongos Endogâmicos C57BL , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia
11.
Methods Mol Biol ; 2576: 67-94, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36152178

RESUMO

Cannabis plant has been used from ancient times with therapeutic purposes for treating human pathologies, but the identification of the cellular and molecular mechanisms underlying the therapeutic properties of the phytocannabinoids, the active compounds in this plant, occurred in the last years of the past century. In the late 1980s and early 1990s, seminal studies demonstrated the existence of cannabinoid receptors and other elements of the so-called endocannabinoid system. These G protein-coupled receptors (GPCRs) are a key element in the functions assigned to endocannabinoids and appear to serve as promising pharmacological targets. They include CB1, CB2, and GPR55, but also non-GPCRs can be activated by endocannabinoids, like ionotropic receptor TRPV1 and even nuclear receptors of the PPAR family. Their activation, inhibition, or simply modulation have been associated with numerous physiological effects at both central and peripheral levels, which may have therapeutic value in different human pathologies, then providing a solid experimental explanation for both the ancient medicinal uses of Cannabis plant and the recent advances in the development of cannabinoid-based specific therapies. This chapter will review the scientific knowledge generated in the last years around the research on the different endocannabinoid-binding receptors and their signaling mechanisms. Our intention is that this knowledge may help readers to understand the relevance of these receptors in health and disease conditions, as well as it may serve as the theoretical basis for the different experimental protocols to investigate these receptors and their signaling mechanisms that will be described in the following chapters.


Assuntos
Canabinoides , Cannabis , Endocanabinoides , Humanos , Receptores Ativados por Proliferador de Peroxissomo , Receptor CB2 de Canabinoide , Receptores de Canabinoides , Receptores Acoplados a Proteínas G
12.
Cureus ; 14(10): e29870, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36348877

RESUMO

Umbilical cord prolapse with ruptured membranes is an obstetric emergency with management consisting of delivery via emergent cesarean delivery. If the umbilical cord prolapses beyond the internal os with intact membranes, there is an opportunity to intervene and reduce the risk of fetal morbidity and mortality. A healthy 30-year-old, gravida 1 para 0 was incidentally found to have a short cervical length at 25 weeks five days on routine anatomy ultrasound evaluation. On evaluation via ultrasound by the maternal-fetal medicine service, the umbilical cord was noted to be prolapsing through the cervix with membranes intact. The cord prolapse with intact membranes resolved after placing the patient in the Trendelenburg position and nifedipine was administered for tocolysis given the uterus was noted to be contracting. For the remainder of the pregnancy, the patient underwent close follow-up and serial ultrasound scans with confirmation of the fetal head as the presenting part. The patient ultimately delivered vaginally at term. Cord prolapse with intact membranes, when identified via ultrasound, can be managed conservatively via Trendelenburg positioning and tocolysis to avoid premature cesarean delivery.

13.
PLoS One ; 16(6): e0252690, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34170917

RESUMO

In areas of low and unstable transmission, malaria cases occur in populations with lower access to malaria services and interventions, and in groups with specific malaria risk exposures often away from the household. In support of the Namibian National Vector Borne Disease Program's drive to better target interventions based upon risk, we implemented a health facility-based case control study aimed to identify risk factors for symptomatic malaria in Zambezi Region, northern Namibia. A total of 770 febrile individuals reporting to 6 health facilities and testing positive by rapid diagnostic test (RDT) between February 2015 and April 2016 were recruited as cases; 641 febrile individuals testing negative by RDT at the same health facilities through June 2016 were recruited as controls. Data on socio-demographics, housing construction, overnight travel, use of malaria prevention and outdoor behaviors at night were collected through interview and recorded on a tablet-based questionnaire. Remotely-sensed environmental data were extracted for geo-located village residence locations. Multivariable logistic regression was conducted to identify risk factors and latent class analyses (LCA) used to identify and characterize high-risk subgroups. The majority of participants (87% of cases and 69% of controls) were recruited during the 2016 transmission season, an outbreak year in Southern Africa. After adjustment, cases were more likely to be cattle herders (Adjusted Odds Ratio (aOR): 4.46 95%CI 1.05-18.96), members of the police or other security personnel (aOR: 4.60 95%CI: 1.16-18.16), and pensioners/unemployed persons (aOR: 2.25 95%CI 1.24-4.08), compared to agricultural workers (most common category). Children (aOR 2.28 95%CI 1.13-4.59) and self-identified students were at higher risk of malaria (aOR: 4.32 95%CI 2.31-8.10). Other actionable risk factors for malaria included housing and behavioral characteristics, including traditional home construction and sleeping in an open structure (versus modern structure: aOR: 2.01 95%CI 1.45-2.79 and aOR: 4.76 95%CI: 2.14-10.57); cross border travel in the prior 30 days (aOR: 10.55 95%CI 2.94-37.84); and outdoor agricultural work at night (aOR: 2.09 95%CI 1.12-3.87). Malaria preventive activities were all protective and included personal use of an insecticide treated net (ITN) (aOR: 0.61 95%CI 0.42-0.87), adequate household ITN coverage (aOR: 0.63 95%CI 0.42-0.94), and household indoor residual spraying (IRS) in the past year (versus never sprayed: (aOR: 0.63 95%CI 0.44-0.90). A number of environmental factors were associated with increased risk of malaria, including lower temperatures, higher rainfall and increased vegetation for the 30 days prior to diagnosis and residing more than 5 minutes from a health facility. LCA identified six classes of cases, with class membership strongly correlated with occupation, age and select behavioral risk factors. Use of ITNs and IRS coverage was similarly low across classes. For malaria elimination these high-risk groups will need targeted and tailored intervention strategies, for example, by implementing alternative delivery methods of interventions through schools and worksites, as well as the use of specific interventions that address outdoor transmission.


Assuntos
Malária Falciparum/prevenção & controle , Ocupações/estatística & dados numéricos , Estações do Ano , Viagem/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Mosquiteiros Tratados com Inseticida/estatística & dados numéricos , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Masculino , Pessoa de Meia-Idade , Namíbia/epidemiologia , Ocupações/classificação , Plasmodium falciparum/fisiologia , Fatores de Risco , Fatores Sexuais , Inquéritos e Questionários , Adulto Jovem
14.
Brain Pathol ; 31(6): e12972, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33983653

RESUMO

The activation of the cannabinoid receptor type-2 (CB2 ) afforded neuroprotection in amyotrophic lateral sclerosis (ALS) models. The objective of this study was to further investigate the relevance of the CB2 receptor through investigating the consequences of its inactivation. TDP-43(A315T) transgenic mice were crossed with CB2 receptor knock-out mice to generate double mutants. Temporal and qualitative aspects of the pathological phenotype of the double mutants were compared to TDP-43 transgenic mice expressing the CB2 receptor. The double mutants exhibited significantly accelerated neurological decline, such that deteriorated rotarod performance was visible at 7 weeks, whereas rotarod performance was normal up to 11 weeks in transgenic mice with intact expression of the CB2 receptor. A morphological analysis of spinal cords confirmed an earlier death (visible at 65 days) of motor neurons labelled with Nissl staining and ChAT immunofluorescence in double mutants compared to TDP-43 transgenic mice expressing the CB2 receptor. Evidence of glial reactivity, measured using GFAP and Iba-1 immunostaining, was seen in double mutants at 65 days, but not in TDP-43 transgenic mice expressing the CB2 receptor. However, at 90 days, both genotypes exhibited similar changes for all these markers, although surviving motor neurons of transgenic mice presented some morphological abnormalities in absence of the CB2 receptor that were not as evident in the presence of this receptor. This faster deterioration seen in double mutants led to premature mortality compared with TDP-43 transgenic mice expressing the CB2 receptor. We also investigated the consequences of a pharmacological inactivation of the CB2 receptor using the selective antagonist AM630 in TDP-43 transgenic mice, but results showed only subtle trends towards a greater deterioration. In summary, our results confirmed the potential of the CB2 receptor agonists as a neuroprotective therapy in ALS and strongly support the need to progress towards an evaluation of this potential in patients.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Encéfalo/patologia , Neurônios Motores/patologia , Destreza Motora/fisiologia , Receptor CB2 de Canabinoide/genética , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/fisiopatologia , Animais , Encéfalo/metabolismo , Encéfalo/fisiopatologia , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Modelos Animais de Doenças , Camundongos , Camundongos Transgênicos , Neurônios Motores/metabolismo , Receptor CB2 de Canabinoide/metabolismo , Teste de Desempenho do Rota-Rod , Medula Espinal/metabolismo , Medula Espinal/patologia , Medula Espinal/fisiopatologia
15.
Br J Pharmacol ; 178(6): 1373-1387, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33486755

RESUMO

Cannabinoids form a singular group of plant-derived compounds, endogenous lipids and synthetic derivatives with multiple therapeutic effects exerted by targeting different elements of the endocannabinoid system. One of their therapeutic applications is the preservation of neuronal integrity exerted by attenuating the multiple neurotoxic events that kill neurons in neurodegenerative disorders. In this review, we will address the potential of cannabinoids as neuroprotective agents in amyotrophic lateral sclerosis (ALS), a devastating neurodegenerative disorder characterized by muscle denervation, atrophy and paralysis, and progressive deterioration in upper and/or lower motor neurons. The emphasis will be paid on the cannabinoid type 2 (CB2 ) receptor, whose activation limits glial reactivity, but the potential of additional endocannabinoid-related targets will be also addressed. The evidence accumulated so far at the preclinical level supports the need to soon move towards the patients and initiate clinical trials to confirm the potential of cannabinoid-based medicines as disease modifiers in ALS. LINKED ARTICLES: This article is part of a themed issue on Neurochemistry in Japan. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.6/issuetoc.


Assuntos
Esclerose Lateral Amiotrófica , Canabinoides , Esclerose Lateral Amiotrófica/tratamento farmacológico , Canabinoides/uso terapêutico , Progressão da Doença , Endocanabinoides , Humanos , Neurônios Motores , Receptor CB1 de Canabinoide , Receptor CB2 de Canabinoide
16.
Nephrol Dial Transplant ; 25(2): 605-10, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19783594

RESUMO

BACKGROUND: Heart failure (HF) is a major health problem in developed countries. HF is a progressive, lethal disorder, even with adequate treatment. There exists a vicious circle in the pathophysiology of HF that perpetuates and magnifies the problem. Concomitant fluid accumulation may worsen the congestive HF, it is responsible for numerous hospitalizations and it is an important cause of mortality. In this situation, any means of fluid removal may aid in the management of these patients. The objective of this study was to evaluate the efficacy of peritoneal dialysis (PD) in the treatment of refractory HF in terms of functional status, hospitalization and mortality. We also determined the improvement in health-related quality of life with the use of PD, and examined the economic consequences of its use. METHODS: We conducted a single centre, prospective, non-randomized study involving patients showing symptoms and signs of congestive HF refractory to maximum tolerable drug treatment. All of them were treated with PD. We analysed physical and biochemical determinations, functional status (according to the NYHA classification) and echocardiogram parameters. Also, to determine the efficacy of the technique we compared the perceived state of health (measured by the EQ5D) to PD patients respect to those reported with conservative therapies. Finally, we carried out a cost-utility evaluation measured by the incremental cost-utility ratio between these two options. RESULTS: Seventeen patients (65% men, 64 +/- 9 years) were included in the study, and 12 were still undergoing PD treatment at the end of the follow-up period (15 +/- 9 months). All patients improved their NYHA functional status (65% two classes; the rest, one; P < 0.001), with an important improvement in their pulmonary artery systolic pressure (44 +/- 12 versus 27 +/- 9 mmHg; P = 0.007), but no changes in left ventricular ejection fraction. Hospitalization rates underwent a dramatic reduction (from 62 +/- 16 to 11 +/- 5 days/patient/year; P = 0.003) before and after PD treatment. PD treatment raised life expectancy of 82% after 12 months of treatment, and 70% and 56% after 18 and 24 months, respectively, much better outcomes than those reported about conservative therapies, which only use diverse diuretic regimens. PD was associated with a higher perception state of health than the conservative therapy (0.6727 versus 0.4305; P < 0.01). Finally, we found that PD is cost-effective compared with the conservative therapy. CONCLUSIONS: We demonstrate that congestive HF programmes should consider offering PD in hope of seeing better functional status, reduced morbidity and mortality, better quality of life as well as reduced health care costs.


Assuntos
Insuficiência Cardíaca/terapia , Diálise Peritoneal , Custos e Análise de Custo , Feminino , Hemodiafiltração , Humanos , Masculino , Pessoa de Meia-Idade , Diálise Peritoneal/economia , Estudos Prospectivos
17.
Sci Rep ; 10(1): 4449, 2020 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-32157143

RESUMO

Pathogenesis of amyotrophic lateral sclerosis (ALS), a devastating disease where no treatment exists, involves the compartmentalization of the nuclear protein TDP-43 (TAR DNA-binding protein 43) in the cytoplasm which is promoted by its aberrant phosphorylation and others posttranslational modifications. Recently, it was reported that CK-1δ (protein casein kinase-1δ) is able to phosphorylate TDP-43. Here, the preclinical efficacy of a benzothiazole-based CK-1δ inhibitor IGS-2.7, both in a TDP-43 (A315T) transgenic mouse and in a human cell-based model of ALS, is shown. Treatment with IGS-2.7 produces a significant preservation of motor neurons in the anterior horn at lumbar level, a decrease in both astroglial and microglial reactivity in this area, and in TDP-43 phosphorylation in spinal cord samples. Furthermore, the recovery of TDP-43 homeostasis (phosphorylation and localization) in a human-based cell model from ALS patients after treatment with IGS-2.7 is also reported. Moreover, we have shown a trend to increase in CK-1δ mRNA in spinal cord and significantly in frontal cortex of sALS cases. All these data show for the first time the in vivo modulation of TDP-43 toxicity by CK-1δ inhibition with IGS-2.7, which may explain the benefits in the preservation of spinal motor neurons and point to the relevance of CK-1δ inhibitors in a future disease-modifying treatment for ALS.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Caseína Quinase Idelta/antagonistas & inibidores , Proteínas de Ligação a DNA/metabolismo , Neurônios Motores/citologia , Inibidores de Proteínas Quinases/farmacologia , Medula Espinal/citologia , Idoso , Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/metabolismo , Animais , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Fosforilação , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo
18.
Disaster Med Public Health Prep ; 13(4): 774-776, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30626464

RESUMO

Research is lacking around how best to approach trauma care in resource poor settings, particularly in remote areas such as the islands of the South Pacific. Without examples of successful treatment of high-risk cases in these settings, countries are unable to move forward with developing policies and standardized procedures for emergency care.The Republic of Kiribati is a Pacific Island nation composed of 33 islands spanning over 2,000 miles in the central Pacific Ocean. With the only hospital located on Kiritimati Island and inadequate boat transportation, the government recently committed to providing an aircraft for patients to receive appropriate medical care. In 2016, a 20-year-old female, primigravida, on a neighboring island, failed to progress in labor for 24 hours and needed an emergency cesarean section. A radio call was made to Kiritimati, and a team consisting of a general surgeon, nurse, and a laboratory technician was dispatched. The patient was brought to the local clinic and flown to Kiritimati where a team was prepared to perform the cesarean section.The successful patient evacuation emphasizes the importance of a dedicated health care team, government commitment, and the constant quality communication when approaching feasibility of trauma and emergency care. (Disaster Med Public Health Preparedness. 2019;13:774-776).


Assuntos
Serviços Médicos de Emergência/normas , Transferência de Pacientes/métodos , Cesárea/métodos , Países em Desenvolvimento , Serviços Médicos de Emergência/métodos , Serviços Médicos de Emergência/estatística & dados numéricos , Feminino , Humanos , Micronésia , Transferência de Pacientes/tendências , Gravidez , Ferimentos e Lesões/terapia , Adulto Jovem
19.
Br J Pharmacol ; 176(10): 1585-1600, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-29574689

RESUMO

BACKGROUND AND PURPOSE: Cannabinoid CB2 receptors are up-regulated in reactive microglia in the spinal cord of TDP-43 (A315T) transgenic mice, an experimental model of amyotrophic lateral sclerosis. To determine whether this up-regulation can be exploited pharmacologically, we investigated the effects of different treatments that affect CB2 receptor function. EXPERIMENTAL APPROACH: We treated TDP-43 (A315T) transgenic mice with the non-selective agonist WIN55,212-2, alone or combined with selective CB1 or CB2 antagonists, as well as with the selective CB2 agonist HU-308, and evaluated their effects on the pathological phenotype. KEY RESULTS: WIN55,212-2 had modest beneficial effects in the rotarod test, Nissl staining of motor neurons, and GFAP and Iba-1 immunostainings in the spinal cord, which were mediated in part by CB2 receptor activation. HU-308 significantly improved the rotarod performance of the transgenic mice, with complete preservation of Nissl-stained motor neurons in the ventral horn. Reactive astrogliosis labelled with GFAP was also attenuated by HU-308 in the dorsal and ventral horns, in which CB2 receptors colocalize with this astroglial marker. Furthermore, HU-308 reduced the elevated Iba-1 immunostaining in the ventral horn of TDP-43 transgenic mice, but did not affect this immunoreactivity in white matter, in which CB2 receptors also colocalize with this microglial marker. CONCLUSIONS AND IMPLICATIONS: Our study shows an important role for glial CB2 receptors in limiting the progression of the pathological phenotype in TDP-43 (A315T) transgenic mice. Such benefits appear to derive from the activation of CB2 receptors concentrated in astrocytes and reactive microglia located in spinal dorsal and ventral horns. LINKED ARTICLES: This article is part of a themed section on 8th European Workshop on Cannabinoid Research. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v176.10/issuetoc.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Benzoxazinas/uso terapêutico , Agonistas de Receptores de Canabinoides/uso terapêutico , Canabinoides/uso terapêutico , Microglia/efeitos dos fármacos , Morfolinas/uso terapêutico , Naftalenos/uso terapêutico , Receptor CB2 de Canabinoide/agonistas , Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Animais , Proteínas de Ligação a DNA/genética , Modelos Animais de Doenças , Camundongos Transgênicos , Microglia/metabolismo , Atividade Motora/efeitos dos fármacos , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Teste de Desempenho do Rota-Rod
20.
Front Mol Neurosci ; 12: 94, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31068788

RESUMO

Spinocerebellar ataxias (SCAs) are a group of hereditary and progressive neurological disorders characterized by a loss of balance and motor coordination typically associated with cerebellar atrophy. The most prevalent SCA types are all polyQ disorders like Huntington's disease, sharing the most relevant events in pathogenesis with this basal ganglia disorder, but with most of the damage concentrated in cerebellar neurons, and in their afferent and efferent connections (e.g., brainstem nuclei). SCAs have no cure and effective symptom-alleviating and disease-modifying therapies are not currently available. However, based on results obtained in studies conducted in murine models and information derived from analyses in post-mortem tissue samples from patients, which show notably higher levels of CB1 receptors found in different cerebellar neuronal subpopulations, the blockade of these receptors has been proposed for acutely modulating motor incoordination in cerebellar ataxias, whereas their chronic activation has been proposed for preserving specific neuronal losses. Additional studies in post-mortem tissues from SCA patients have also demonstrated elevated levels of CB2 receptors in Purkinje neurons as well as in glial elements in the granular layer and in the cerebellar white matter, with a similar profile found for endocannabinoid hydrolyzing enzymes, then suggesting that activating CB2 receptors and/or inhibiting these enzymes may also serve to develop cannabinoid-based neuroprotective therapies. The present review will address both aspects. On one hand, the endocannabinoid system becomes dysregulated in the cerebellum and also in other CNS structures (e.g., brainstem, basal ganglia) in SCAs, which may contribute to the progression of pathogenic events in these diseases. On the other hand, these endocannabinoid alterations may be pharmacologically corrected or enhanced, and this may have therapeutic consequences, either alleviating specific symptoms or eliciting neuroprotective effects, an objective presently under investigation.

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