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1.
J Neurochem ; 163(4): 338-356, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36205031

RESUMO

Human immunodeficiency virus (HIV) neuroinvasion occurs early after infection through the trafficking of virus-infected immune cells into the central nervous system (CNS) and viral dissemination into the brain. There, it can infect resident brain cells including astrocytes, the most abundant cell type that is crucial to brain homeostasis. In this report, we examined the HIV-related mechanism able to induce bystander cell death in astrocytes mediated by cell-to-cell contact with productively infected (PI) ones. We first demonstrate that HIV-induced bystander cell death involves mitochondrial dysfunction that promotes exacerbated reactive oxygen species production. Such a phenomenon is a contagious cell death that requires contact with HIV-PI astrocytes that trigger caspase-dependent (apoptosis and pyroptosis) and caspase-independent cell death pathways. The HIV accessory proteins Nef, Vpu, and Vpr counteract astrocyte death among PI cells but, in contrast, participate to promote contagious bystander cell death by inducing mitochondrial reactive oxygen species production. Our findings indicate that astrocytes PI by HIV became capable to counteract infection-derived death signals, surviving, and spreading the bystander cell death into neighboring uninfected cells by a cell-to-cell contact-dependent mechanism. Considering that astrocytes have been proposed as a long-term HIV reservoir in the CNS, ascertaining the mechanism of survival and contagious bystander death will afford clear targets in the current goal to achieve a functional cure.


Assuntos
Infecções por HIV , HIV-1 , Humanos , Astrócitos/metabolismo , HIV-1/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Morte Celular , Caspases/metabolismo
2.
Front Immunol ; 13: 992370, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225925

RESUMO

The COVID-19 pandemic has particularly affected older adults residing in nursing homes, resulting in high rates of hospitalisation and death. Here, we evaluated the longitudinal humoral response and neutralising capacity in plasma samples of volunteers vaccinated with different platforms (Sputnik V, BBIBP-CorV, and AZD1222). A cohort of 851 participants, mean age 83 (60-103 years), from the province of Buenos Aires, Argentina were included. Sequential plasma samples were taken at different time points after vaccination. After completing the vaccination schedule, infection-naïve volunteers who received either Sputnik V or AZD1222 exhibited significantly higher specific anti-Spike IgG titers than those who received BBIBP-CorV. Strong correlation between anti-Spike IgG titers and neutralising activity levels was evidenced at all times studied (rho=0.7 a 0.9). Previous exposure to SARS-CoV-2 and age <80 years were both associated with higher specific antibody levels. No differences in neutralising capacity were observed for the infection-naïve participants in either gender or age group. Similar to anti-Spike IgG titers, neutralising capacity decreased 3 to 9-fold at 6 months after initial vaccination for all platforms. Neutralising capacity against Omicron was between 10-58 fold lower compared to ancestral B.1 for all vaccine platforms at 21 days post dose 2 and 180 days post dose 1. This work provides evidence about the humoral response and neutralising capacity elicited by vaccination of a vulnerable elderly population. This data could be useful for pandemic management in defining public health policies, highlighting the need to apply reinforcements after a complete vaccination schedule.


Assuntos
COVID-19 , Idoso , Idoso de 80 Anos ou mais , Anticorpos Antivirais , Argentina/epidemiologia , COVID-19/epidemiologia , COVID-19/prevenção & controle , ChAdOx1 nCoV-19 , Humanos , Imunoglobulina G , Pandemias , SARS-CoV-2 , Vacinação
3.
Front Immunol ; 13: 909995, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36263055

RESUMO

Background: Recent studies have shown the presence of SARS-CoV-2-specific antibodies in the milk of breastfeeding mothers vaccinated with mRNA and convalescent. However, limited information is available in lactating women receiving other vaccine platforms used in developing countries, such as the inactivated SARS-CoV-2 vaccine BBIBP-CorV (Sinopharm) and the non-replicating adenovirus vaccines Sputnik V (Gamaleya Institute) and ChAdOx1-S (Oxford AstraZeneca). Methods: Here, we evaluated anti-SARS-CoV-2 IgG and IgA levels in both serum and milk samples using a longitudinal and a cross-sectional cohort of 208 breastfeeding vaccinated women from Argentina with or without previous SARS-CoV-2 infection. Results: The analysis showed that IgA levels remain constant in serum and milk of breastfeeding mothers between the first and second doses of vector-based vaccines (Sputnik V and ChAdOx1-S). After the second dose, anti-spike IgA was found positive in 100% of the serum samples and in 66% of breastmilk samples. In addition, no significant differences in milk IgA levels were observed in participants receiving BBIBP-CorV, Sputnik V or ChAdOx1-S. IgG levels in milk increased after the second dose of vector-based vaccines. Paired longitudinal samples taken at 45 and 120 days after the second dose showed a decrease in milk IgG levels over time. Study of IgA levels in serum and milk of vaccinated naïve of infection and vaccinated-convalescent breastfeeding participants showed significantly higher levels in vaccinated-convalescent than in participants without previous infection. Conclusion: This study is relevant to understand the protection against SARS-CoV-2 by passive immunity in newborns and children who are not yet eligible to receive vaccination.


Assuntos
Vacinas contra Adenovirus , COVID-19 , Vacinas Virais , Recém-Nascido , Criança , Humanos , Feminino , Vacinas contra COVID-19 , SARS-CoV-2 , Leite Humano , Estudos Transversais , Lactação , COVID-19/prevenção & controle , Anticorpos Antivirais , Imunoglobulina G , Imunoglobulina A , RNA Mensageiro
4.
Cell Rep Med ; 3(8): 100706, 2022 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-35926505

RESUMO

Heterologous vaccination against coronavirus disease 2019 (COVID-19) provides a rational strategy to rapidly increase vaccination coverage in many regions of the world. Although data regarding messenger RNA (mRNA) and ChAdOx1 vaccine combinations are available, there is limited information about the combination of these platforms with other vaccines widely used in developing countries, such as BBIBP-CorV and Sputnik V. Here, we assess the immunogenicity and reactogenicity of 15 vaccine combinations in 1,314 participants. We evaluate immunoglobulin G (IgG) anti-spike response and virus neutralizing titers and observe that a number of heterologous vaccine combinations are equivalent or superior to homologous schemes. For all cohorts in this study, the highest antibody response is induced by mRNA-1273 as the second dose. No serious adverse events are detected in any of the schedules analyzed. Our observations provide rational support for the use of different vaccine combinations to achieve wide vaccine coverage in the shortest possible time.


Assuntos
COVID-19 , Vacinas Virais , Vacina de mRNA-1273 contra 2019-nCoV , Anticorpos Antivirais , COVID-19/prevenção & controle , Humanos , Imunização , RNA Mensageiro/genética , SARS-CoV-2 , Vacinação
5.
Brain Sci ; 12(8)2022 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-36009103

RESUMO

Ataxia is a constellation of symptoms that involves a lack of coordination, imbalance, and difficulty walking. Hereditary ataxia occurs when a person is born with defective genes, and this degenerative disorder may progress for several years. There is no effective cure for ataxia, so we need to search for new treatments. Recently, interest in riluzole in the treatment of ataxia has emerged. We conducted this systematic review to analyze the safety and efficacy of riluzole for treating hereditary ataxia in recent clinical trials. We conducted a systematic review using PubMed and Google Scholar as databases in search of this relationship. We used the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Meta-analysis of Observational Studies in Epidemiology (MOOSE) protocols to conduct this study. For inclusion criteria, we included full-text clinical trials on humans written in English and found three clinical trials. We excluded case reports, literature reviews, systematic reviews, and meta-analyses for this analysis. We aimed to evaluate the Scale for the Assessment and Rating of Ataxia (SARA) score, the International Cooperative Ataxia Rating Scale (ICARS) score, and the safety of the medication. Two out of the three clinical trials showed statistically significant clinical improvement in the ICARS and SARA scores, while the other trial did not show improvement in the clinical or radiological outcomes. The drug was safe in all clinical trials. Overall, the results of this analysis of riluzole for the treatment of hereditary ataxia are encouraging. Further clinical trials are needed to investigate the efficacy of riluzole on hereditary ataxia.

6.
Cureus ; 14(7): e27154, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36004035

RESUMO

Protocadherin 19 (PCDH19) syndrome is inherited as an X-linked pattern and affects mainly females. This syndrome is caused by a mutation in the PCDH19 gene encoding for the protocadherin protein. It is characterized by refractory seizures during febrile episodes with neuropsychiatric manifestations. There is no consensus on the treatment of PCDH19. We conducted a literature review to investigate the main drugs used for this syndrome, and to evaluate the best possible course of adjuvant treatment for these patients. We used an advanced PubMed search strategy with the following inclusion criteria: a) full-text papers, b) English Language, and c) studies conducted in humans. Exclusion criteria: a) literature reviews, b) systematic reviews, and c) metanalysis. We gathered 26 observational papers to conduct this literature review on clobazam and bromide which have been shown to reduce seizures by 50%. Corticosteroids improved neurological symptoms during the episodes in a few patients. Nevertheless, they recurred after a few months. Preliminary results of ganaxolone, which is still under study, demonstrated a reduction of 60% in seizure episodes. A ketogenic diet has been studied to treat several refractory epilepsies, including PCDH19; it has promising results as effective adjuvant therapy in the resolution of status epilepticus, suggesting it could be used as part of the treatment in early childhood. Stiripentol was given as adjuvant therapy in a patient with PCDH19 epilepsy resulting in the most extended period of seizure-free episodes, but more studies must be performed to assess its efficacy.

8.
Cureus ; 14(6): e25808, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35822151

RESUMO

PCDH19 syndrome is a monogenic epilepsy related to the protein protocadherin-19 (PCDH19) gene, which encodes for a protein important for brain development. The protein also seems to regulate gamma-aminobutyric acid type A receptors (GABA(A)(R)). The disease presents with refractory epilepsy that is characterized by seizures occurring in clusters. Till now, the pathophysiology of the disease is mainly unknown, so we conducted a literature review to elucidate the pathophysiology of PCDH19-related epilepsy. We used two databases to investigate this literature review (Google Scholar and PubMed). We selected full-text papers that are published in the English language and published after the year 2000. We selected initially 64 papers and ended up with 29 to conduct this literature review. We found four main theories for the pathophysiology of PCDH19-related epilepsy: GABA(A)(R) dysregulation, blood-brain barrier (BBB) dysfunction, cellular interference, and the AKR1C1-3 gene product deficiency. GABA(A)(R) dysfunction and expression cause decreased effective inhibitory currents predisposing patients to epilepsy. BBB dysfunction allows the passage of methyl-D-aspartate (NMDA)-type glutamate receptor antibodies (abs-NR) through the BBB susceptible membrane. The cellular interference hypothesis establishes that the mutant and non-mutant cells interfere with each other's communication within the same tissue. Women are more susceptible to being affected by this hypothesis as men only have one copy of the x gene and interference is mediated by this gene, meaning that it cannot occur in them. Finally, downregulation and deficiency of the AKR1C3/AKR1C2 products lead to decreasing levels of allopregnanolone, which diminish the regulation of GABA(A)(R).

9.
J Infect Dis ; 226(10): 1717-1720, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-35723970

RESUMO

Infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant is usually asymptomatic or mild and appears to be poorly immunogenic at least in unvaccinated individuals. Here, we found that health care workers vaccinated with 2 doses of Sputnik V and a booster dose of ChAdOx1 mount a vigorous neutralizing-antibody response after Omicron breakthrough infection.


Assuntos
Formação de Anticorpos , COVID-19 , Humanos , SARS-CoV-2 , COVID-19/prevenção & controle , Vacinação , Anticorpos Neutralizantes , Anticorpos Antivirais
10.
Clocks Sleep ; 4(2): 287-299, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35735605

RESUMO

Kleine-Levin syndrome (KLS) is characterized by episodes of hypersomnia. Additionally, these patients can present with hyperphagia, hypersexuality, abnormal behavior, and cognitive dysfunction. Functional neuroimaging studies such as fMRI-BOLD, Positron Emission Tomography (PET) or SPECT help us understand the neuropathological bases of different disorders. We conducted a systematic review to investigate the neuroimaging features of KLS patients and their clinical correlations. This systematic review was conducted by following the Meta-Analysis of Observational Studies in Epidemiology (MOOSE) and PRISMA protocol reporting guidelines. We aim to investigate the clinical correlation with neuroimaging among patients with KLS. We included only studies written in the English language in the last 20 years, conducted on humans; 10 studies were included. We excluded systematic reviews, metanalysis, and case reports. We found that there are changes in functional imaging studies during the symptomatic and asymptomatic periods as well as in between episodes in patients with K.L.S. The areas most reported as affected were the hypothalamic and thalamic regions, which showed hypoperfusion and, in a few cases, hyperperfusion; areas such as the frontal, parietal, occipital and the prefrontal cortex all showed alterations in cerebral perfusion. These changes in cerebral blood flow and regions vary according to the imaging (SPECT, PET SCAN, or fMRI) and the task performed while imaging was performed. We encountered conflicting data between studies. Hyper insomnia, the main feature of this disease during the symptomatic periods, was associated with decreased thalamic activity. Other features of K.L.S., such as apathy, hypersexuality, and depersonalization, were also correlated with functional imaging changes. There were also findings that correlated with working memory deficits seen in this stage during the asymptomatic periods. Hyperactivity of the thalamus and hypothalamus were the main features shown during the asymptomatic period. Additionally, functional imaging tends to improve with a longer course of the disease, which suggests that K.L.S. patients outgrow the disease. These findings should caution physicians when analyzing and correlating neuroimaging findings with the disease.

11.
Neurol Int ; 14(2): 488-496, 2022 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-35736621

RESUMO

(1) Background: Reversible cerebral vasoconstriction syndrome (RCVS) encompasses a clinical and radiological diagnosis characterized by recurrent thunderclap headache, with or without focal deficits due to multifocal arterial vasoconstriction and dilation. RCVS can be correlated to pregnancy and exposure to certain drugs. Currently, the data on prevalence of RCVS in the postpartum period is lacking. We aim to investigate the prevalence of RCVS in the postpartum period and the rate of hemorrhagic complications of RCVS among the same group of patients; (2) Methods: We conducted the metanalysis by using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA), and Meta-Analyses and Systematic Reviews of Observational Studies in Epidemiology (MOOSE) protocol. To analyze the Bias, we used the Ottawa Newcastle scale tool. We included only full-text observational studies conducted on humans and written in English. We excluded Literature Reviews, Systematic Reviews, and Metanalysis. Additionally, we excluded articles that did not document the prevalence of RCVS in the postpartum period (3). Results: According to our analysis, the Prevalence of RCVS in the postpartum period was 129/1083 (11.9%). Of these, 51/100 (52.7%) patients had hemorrhagic RCVS vs. 49/101 (49.5%) with non-hemorrhagic RCVS. The rates of Intracerebral Hemorrhage (ICH) and Subarachnoid Hemorrhage (SAH) were (51.6% and 10.7%, respectively. ICH seems to be more common than.; (4) Conclusions: Among patients with RCVS, the prevalence in PP patients is relativity high. Pregnant women with RCVS have a higher recurrence of hemorrhagic vs. non-hemorrhagic RCVS. Regarding the type of Hemorrhagic RCVS, ICH is more common than SAH among patients in the postpartum period. Female Sex, history of migraine, and older age group (above 45) seem to be risk factors for H-RCVS. Furthermore, recurrence of RCVS is associated with a higher age group (above 45). Recurrence of RCVS is more commonly idiopathic than being triggered by vasoactive drugs in the postpartum period.

12.
Cureus ; 14(4): e24529, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35651458

RESUMO

Stroke is a leading cause of death and disability, especially in certain ethnic groups. Impaired consciousness is a common outcome in stroke patients, serving as a predictor of prognosis and mortality. Lately, there has been increased interest in drugs such as Levodopa (LD), which have been found to promote wakefulness. To further appreciate this association, we gathered updated evidence of this novel therapeutic approach and compared it, evaluating its clinical use in an acute stroke setting. We carried out a systematic review of clinical trials conducted exclusively on stroke patients who received levodopa. Four clinical trials were reviewed and analyzed after applying the inclusion/exclusion criteria. The use of levodopa showed positive results in four of the clinical trials, and statistically significant results in 3/4 of the studies; however, more studies need to be conducted to corroborate these results.

14.
mBio ; : e0344221, 2022 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-35073758

RESUMO

Recent studies have shown a temporal increase in the neutralizing antibody potency and breadth to SARS-CoV-2 variants in coronavirus disease 2019 (COVID-19) convalescent individuals. Here, we examined longitudinal antibody responses and viral neutralizing capacity to the B.1 lineage virus (Wuhan related), to variants of concern (VOC; Alpha, Beta, Gamma, and Delta), and to a local variant of interest (VOI; Lambda) in volunteers receiving the Sputnik V vaccine in Argentina. Longitudinal serum samples (N = 536) collected from 118 volunteers obtained between January and October 2021 were used. The analysis indicates that while anti-spike IgG levels significantly wane over time, the neutralizing capacity for the Wuhan-related lineages of SARS-CoV-2 and VOC is maintained within 6 months of vaccination. In addition, an improved antibody cross-neutralizing ability for circulating variants of concern (Beta and Gamma) was observed over time postvaccination. The viral variants that displayed higher escape to neutralizing antibodies with respect to the original virus (Beta and Gamma variants) were the ones showing the largest increase in susceptibility to neutralization over time after vaccination. Our observations indicate that serum neutralizing antibodies are maintained for at least 6 months and show a reduction of VOC escape to neutralizing antibodies over time after vaccination. IMPORTANCE Vaccines have been produced in record time for SARS-CoV-2, offering the possibility of halting the global pandemic. However, inequalities in vaccine accessibility in different regions of the world create a need to increase international cooperation. Sputnik V is a recombinant adenovirus-based vaccine that has been widely used in Argentina and other developing countries, but limited information is available about its elicited immune responses. Here, we examined longitudinal antibody levels and viral neutralizing capacity elicited by Sputnik V vaccination. Using a cohort of 118 volunteers, we found that while anti-spike antibodies wane over time, the neutralizing capacity to viral variants of concern and local variants of interest is maintained within 4 months of vaccination. In addition, we observed an increased cross-neutralization activity over time for the Beta and Gamma variants. This study provides valuable information about the immune response generated by a vaccine platform used in many parts of the world.

15.
Zookeys ; 1063: 23-48, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720623

RESUMO

Seasonally dry forests (SDFs) are one of the most challenging ecosystems for amphibians, fueling the diversity of this group of vertebrates. An updated inventory of native amphibians present in the Equatorial SDF is provided, which extends along the Pacific coast of Ecuador and northwestern Peru. The study is based on an extensive field sampling (two thirds of the total records) carried out throughout the Equatorial SDF, along with a compilation of the available information on distribution of amphibians in the region from published scientific papers, museum collections and on-line databases. The final dataset included 2,032 occurrence records for 30 amphibian species, belonging to eight anuran families. Additionally, data regarding conservation status, habitat use, spawn deposition site, reproductive mode, and body size, along with an identification key for all encountered species are provided. The results indicate a strong sampling bias with a deficit in the Peruvian part of the study area, and a need for urgent inventories targeted at under-sampled areas, using modern taxonomic methods. The study emphasizes the conservation priorities in the Equatorial SDF, based on the distribution, conservation status and life-history data. This information should be useful for the local authorities and institutions involved in the management and conservation of biodiversity in SDF.

16.
PLoS One ; 16(10): e0258454, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34705824

RESUMO

We describe a new species of rain frog of the genus Pristimantis from the city of Loja, Southern Ecuador, based on an integrative taxonomy approach, combining molecular, morphological and bioacoustics data. Pristimantis lojanus sp. nov. is a medium sized species of the phylogenetically strongly supported P. phoxocephalus group, and its sister species is P. torresi. The new species can be easily distinguished from its closest congeners and morphologically similar species (that also have acuminate snout with a fleshy keel) by its characteristic advertisement call and morphological features (dorsum finely tuberculate with scattered larger tubercles, flanks without longitudinal lateral folds, no markings in axilla, groin or on concealed limb surfaces, and bronze iris). Additionally, we describe the advertisement call of its sister species, P. torresi. Finally, we detail the current situation of the amphibian species present in the city of Loja and its surroundings.


Assuntos
Anuros , Distribuição Animal , Animais , Equador , Filogenia
17.
Cell Rep Med ; 2(8): 100359, 2021 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-34308389

RESUMO

Massive vaccination offers great promise for halting the global COVID-19 pandemic. However, the limited supply and uneven vaccine distribution create an urgent need to optimize vaccination strategies. We evaluate SARS-CoV-2-specific antibody responses after Sputnik V vaccination of healthcare workers in Argentina, measuring IgG anti-spike titers and neutralizing capacity after one and two doses in a cohort of naive or previously infected volunteers. By 21 days after receiving the first dose of the vaccine, 94% of naive participants develop spike-specific IgG antibodies. A single Sputnik V dose elicits higher antibody levels and virus-neutralizing capacity in previously infected individuals than in naive ones receiving the full two-dose schedule. The high seroconversion rate after a single dose in naive participants suggests a benefit of delaying administration of the second dose to increase the number of people vaccinated. The data presented provide information for guiding public health decisions in light of the current global health emergency.


Assuntos
Vacinas contra COVID-19/imunologia , COVID-19/prevenção & controle , SARS-CoV-2/imunologia , Vacinas Sintéticas/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Anticorpos Antivirais/imunologia , Argentina/epidemiologia , COVID-19/imunologia , Chlorocebus aethiops , Células HEK293 , Pessoal de Saúde , Humanos , Pandemias , SARS-CoV-2/patogenicidade , Soroconversão , Glicoproteína da Espícula de Coronavírus/imunologia , Vacinação , Vacinas , Células Vero
18.
PLoS One ; 16(5): e0251027, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33956885

RESUMO

Ecuador is one of the most biodiverse countries in the world, but faces severe pressures and threats to its natural ecosystems. Numerous species have declined and require to be objectively evaluated and quantified, as a step towards the development of conservation strategies. Herein, we present an updated National Red List Assessment for amphibian species of Ecuador, with one of the most detailed and complete coverages for any Ecuadorian taxonomic group to date. Based on standardized methodologies that integrate taxonomic work, spatial analyses, and ecological niche modeling, we assessed the extinction risk and identified the main threats for all Ecuadorian native amphibians (635 species), using the IUCN Red List Categories and Criteria. Our evaluation reveals that 57% (363 species) are categorized as Threatened, 12% (78 species) as Near Threatened, 4% (26 species) as Data Deficient, and 27% (168 species) as Least Concern. Our assessment almost doubles the number of threatened species in comparison with previous evaluations. In addition to habitat loss, the expansion of the agricultural/cattle raising frontier and other anthropogenic threats (roads, human settlements, and mining/oil activities) amplify the incidence of other pressures as relevant predictors of ecological integrity. Potential synergic effects with climate change and emergent diseases (apparently responsible for the sudden declines), had particular importance amongst the threats sustained by Ecuadorian amphibians. Most threatened species are distributed in montane forests and paramo habitats of the Andes, with nearly 10% of them occurring outside the National System of Protected Areas of the Ecuadorian government. Based on our results, we recommend the following actions: (i) An increase of the National System of Protected Areas to include threatened species. (ii) Supporting the ex/in-situ conservation programs to protect species considered like Critically Endangered and Endangered. (iii) Focalizing research efforts towards the description of new species, as well as species currently categorized as Data Deficient (DD) that may turn out to be threatened. The implementation of the described actions is challenging, but urgent, given the current conservation crisis faced by amphibians.


Assuntos
Anfíbios , Espécies em Perigo de Extinção , Animais , Anuros , Bufonidae , Conservação dos Recursos Naturais/métodos , Bases de Dados como Assunto , Ecossistema , Equador , Espécies em Perigo de Extinção/estatística & dados numéricos
19.
Front Cell Dev Biol ; 9: 640094, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33816487

RESUMO

Mitophagy and zymophagy are selective autophagy pathways early induced in acute pancreatitis that may explain the mild, auto limited, and more frequent clinical presentation of this disease. Adequate mitochondrial bioenergetics is necessary for cellular restoration mechanisms that are triggered during the mild disease. However, mitochondria and zymogen contents are direct targets of damage in acute pancreatitis. Cellular survival depends on the recovering possibility of mitochondrial function and efficient clearance of damaged mitochondria. This work aimed to analyze mitochondrial dynamics and function during selective autophagy in pancreatic acinar cells during mild experimental pancreatitis in rats. Also, using a cell model under the hyperstimulation of the G-coupled receptor for CCK (CCK-R), we aimed to investigate the mechanisms involved in these processes in the context of zymophagy. We found that during acute pancreatitis, mitochondrial O2 consumption and ATP production significantly decreased early after induction of acute pancreatitis, with a consequent decrease in the ATP/O ratio. Mitochondrial dysfunction was accompanied by changes in mitochondrial dynamics evidenced by optic atrophy 1 (OPA-1) and dynamin-related protein 1 (DRP-1) differential expression and ultrastructural features of mitochondrial fission, mitochondrial elongation, and mitophagy during the acute phase of experimental mild pancreatitis in rats. Mitophagy was also evaluated by confocal assay after transfection with the pMITO-RFP-GFP plasmid that specifically labels autophagic degradation of mitochondria and the expression and redistribution of the ubiquitin ligase Parkin1. Moreover, we report for the first time that vacuole membrane protein-1 (VMP1) is involved and required in the mitophagy process during acute pancreatitis, observable not only by repositioning around specific mitochondrial populations, but also by detection of mitochondria in autophagosomes specifically isolated with anti-VMP1 antibodies as well. Also, VMP1 downregulation avoided mitochondrial degradation confirming that VMP1 expression is required for mitophagy during acute pancreatitis. In conclusion, we identified a novel DRP1-Parkin1-VMP1 selective autophagy pathway, which mediates the selective degradation of damaged mitochondria by mitophagy in acute pancreatitis. The understanding of the molecular mechanisms involved to restore mitochondrial function, such as mitochondrial dynamics and mitophagy, could be relevant in the development of novel therapeutic strategies in acute pancreatitis.

20.
Sci Rep ; 11(1): 5667, 2021 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-33707588

RESUMO

Given widespread habitat degradation and loss, reliable indicators are needed that provide a comprehensive assessment of community response to anthropogenic disturbance. The family Phyllostomidae (Order Chiroptera) has frequently been the focus of research evaluating bats' response to habitat disturbance in seasonally dry tropical forests (SDTFs). However, few studies compare this family to the larger bat assemblage to assess its efficacy as a bioindicator. We compared community and species-specific attributes of understory phyllostomid and all understory bat species: (1) along a gradient of habitat disturbance within a human-modified SDTF landscape; and (2) between forest and riparian habitats within each disturbance level. We captured 290 individuals belonging to 13 species and 4 families. Phyllostomid species exhibited greater sensitivity to disturbance than the understory bat community as a whole based on richness and beta diversity. Both groups were more sensitive to disturbance in forest than riparian habitat, but phyllostomid species were more likely to be lost from highly disturbed forest habitat. The two dominant species declined in abundance with disturbance but variation in body condition was species-specific. These results suggest that Phyllostomidae are more effective indicators of human disturbance in SDTF than the understory bat community as a whole and evaluation of bats' response to disturbance is best accomplished with a multifaceted approach.


Assuntos
Quirópteros/fisiologia , Florestas , Estações do Ano , Clima Tropical , Animais , Biodiversidade , Intervalos de Confiança , Geografia , Especificidade da Espécie
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