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1.
Front Bioeng Biotechnol ; 12: 1420183, 2024.
Article in English | MEDLINE | ID: mdl-39175618

ABSTRACT

Introduction: Parkinson's disease (PD) presents a significant challenge in medical science, as current treatments are limited to symptom management and often carry significant side effects. Our study introduces an innovative approach to evaluate the effects of gdnf overexpression mediated by CRISPRa in an in vitro model of Parkinson's disease. The expression of gdnf can have neuroprotective effects, being related to the modulation of neuroinflammation and pathways associated with cell survival, differentiation, and growth. Methods: We have developed a targeted delivery system using a magnetite nanostructured vehicle for the efficient transport of genetic material. This system has resulted in a substantial increase, up to 200-fold) in gdnf expression in an In vitro model of Parkinson's disease using a mixed primary culture of astrocytes, neurons, and microglia. Results and Discussion: The delivery system exhibits significant endosomal escape of more than 56%, crucial for the effective delivery and activation of the genetic material within cells. The increased gdnf expression correlates with a notable reduction in MAO-B complex activity, reaching basal values of 14.8 µU/µg of protein, and a reduction in reactive oxygen species. Additionally, there is up to a 34.6% increase in cell viability in an In vitro Parkinson's disease model treated with the neurotoxin MPTP. Our study shows that increasing gdnf expression can remediate some of the cellular symptoms associated with Parkinson's disease in an in vitro model of the disease using a novel nanostructured delivery system.

2.
Biomedicines ; 11(8)2023 Aug 04.
Article in English | MEDLINE | ID: mdl-37626691

ABSTRACT

BACKGROUND: Chronic kidney disease (CKD) is a multifactorial, world public health problem that often develops as a consequence of acute kidney injury (AKI) and inflammation. Strategies are constantly sought to avoid and mitigate the irreversibility of this disease. One of these strategies is to decrease the inflammation features of AKI and, consequently, the transition to CKD. METHODS: C57Bl6J mice were anesthetized, and surgery was performed to induce unilateral ischemia/reperfusion as a model of AKI to CKD transition. For acute studies, the animals received the Kinin B1 receptor (B1R) antagonist before the surgery, and for the chronic model, the animals received one additional dose after the surgery. In addition, B1R genetically deficient mice were also challenged with ischemia/reperfusion. RESULTS: The absence and antagonism of B1R improved the kidney function following AKI and prevented CKD transition, as evidenced by the preserved renal function and prevention of fibrosis. The protective effect of B1R antagonism or deficiency was associated with increased levels of macrophage type 2 markers in the kidney. CONCLUSIONS: The B1R is pivotal to the evolution of AKI to CKD, and its antagonism shows potential as a therapeutic tool in the prevention of CKD following AKI.

3.
Int J Mol Sci ; 24(12)2023 Jun 17.
Article in English | MEDLINE | ID: mdl-37373426

ABSTRACT

One of the largest health problems worldwide is the development of chronic noncommunicable diseases due to the consumption of hypercaloric diets. Among the most common alterations are cardiovascular diseases, and a high correlation between overnutrition and neurodegenerative diseases has also been found. The urgency in the study of specific damage to tissues such as the brain and intestine led us to use Drosophila melanogaster to study the metabolic effects caused by the consumption of fructose and palmitic acid in specific tissues. Thus, third instar larvae (96 ± 4 h) of the wild Canton-S strain of D. melanogaster were used to perform transcriptomic profiling in brain and midgut tissues to test for the potential metabolic effects of a diet supplemented with fructose and palmitic acid. Our data infer that this diet can alter the biosynthesis of proteins at the mRNA level that participate in the synthesis of amino acids, as well as fundamental enzymes for the dopaminergic and GABAergic systems in the midgut and brain. These also demonstrated alterations in the tissues of flies that may help explain the development of various reported human diseases associated with the consumption of fructose and palmitic acid in humans. These studies will not only help to better understand the mechanisms by which the consumption of these alimentary products is related to the development of neuronal diseases but may also contribute to the prevention of these conditions.


Subject(s)
Drosophila melanogaster , Neurodegenerative Diseases , Animals , Humans , Drosophila melanogaster/metabolism , Fructose/metabolism , Palmitic Acid/pharmacology , Larva/metabolism , Neurodegenerative Diseases/genetics , Gene Expression
4.
Neurochem Res ; 48(1): 250-262, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36066698

ABSTRACT

Parkinson's disease (PD) is characterized by dopaminergic cell loss in the substantia nigra, and PD brains show neuroinflammation, oxidative stress, and mitochondrial dysfunction. The study evaluated the neuroprotective activity of 1α,25-dihydroxy vitamin D3 (VD3), on the rotenone (ROT)-induced cytotoxicity in PC12 cells. The viability parameters were assessed by the MTT and flow cytometry, on cells treated or not with VD3 and/or ROT. Besides, ROS production, cell death, mitochondrial transmembrane potential, reduced GSH, superoxide accumulation, molecular docking (TH and Keap1-Nrf2), and TH, Nrf2, NF-kB, and VD3 receptor protein contents by western blot were evaluated. VD3 was shown to improve the viability of ROT-exposed cells. Cells exposed to ROT showed increased production of ROS and superoxide, which decreased after VD3. ROT decrease in the mitochondrial transmembrane potential was prevented, after VD3 treatment and, VD3 was shown to interact with tyrosine hydroxylase (TH) and Nrf2. While ROT decreased TH, Nrf2, and NF-kB expressions, these effects were reversed by VD3. In addition, VD3 also increased VD3 receptor protein contents and values went back to those of controls after ROT exposure. VD3 protects PC12 cells against ROT damage, by decreasing oxidative stress and improving mitochondrial function. One target seems to be the TH molecule and possibly an indirect Nrf2 activation could also justify its neuroprotective actions on this PC12 cell model of PD.


Subject(s)
Neuroprotective Agents , Parkinson Disease , Rats , Animals , Parkinson Disease/drug therapy , Parkinson Disease/metabolism , Rotenone/toxicity , PC12 Cells , Kelch-Like ECH-Associated Protein 1/metabolism , Reactive Oxygen Species/metabolism , NF-kappa B/metabolism , NF-E2-Related Factor 2/metabolism , Superoxides/metabolism , Molecular Docking Simulation , Neuroprotective Agents/pharmacology , Oxidative Stress
6.
Front Cell Dev Biol ; 10: 962881, 2022.
Article in English | MEDLINE | ID: mdl-36105357

ABSTRACT

The development of cell culture models that recapitulate the etiology and features of nervous system diseases is central to the discovery of new drugs and their translation onto therapies. Neuronal tissues are inaccessible due to skeletal constraints and the invasiveness of the procedure to obtain them. Thus, the emergence of induced pluripotent stem cell (iPSC) technology offers the opportunity to model different neuronal pathologies. Our focus centers on iPSCs derived from amyotrophic lateral sclerosis (ALS) patients, whose pathology remains in urgent need of new drugs and treatment. In this sense, we aim to revise the process to obtain motor neurons derived iPSCs (iPSC-MNs) from patients with ALS as a drug screening model, review current 3D-models and offer a perspective on bioinformatics as a powerful tool that can aid in the progress of finding new pharmacological treatments.

7.
Brain Res Bull ; 187: 111-121, 2022 09.
Article in English | MEDLINE | ID: mdl-35772606

ABSTRACT

Enteric glial cells (EGCs) constitute the majority of the neural population of the enteric nervous system and are found in all layers of the gastrointestinal tract. It is active in enteric functions such as immunomodulation, participating in inflammation and intestinal epithelial barrier (IEB) regulation. Both EGCs and IEB have been described as altered in Parkinson's disease (PD). Using an animal model of PD induced by 6-hydroxydopamine (6-OHDA), we investigated the effect of ongoing neurodegeneration on EGCs and inflammatory response during short periods after model induction. C57Bl/6 male mice were unilaterally injected with 6-OHDA in the striatum. Compared to the control group, 6-OHDA animals showed decreased relative water content in their feces from 1 w after model induction. Moreover, at 1 and 2 w post-induction, groups showed histopathological changes indicative of intestinal inflammation. We identified an increase in IBA1 and GFAP levels in the intestinal mucosa. At an earlier survival of 48 h, we detected an increase in GFAP in the neuromuscular layer, suggesting that it was a primary event for the upregulation of GDNF, TNF-α, and occludin in the intestinal mucosa observed after 1 w. Within 2 w, we identified a decrease in the expression of occludin barrier proteins. Thus, EGCs modulation may be an early enteric signal induced by parkinsonian neurodegeneration, followed by inflammatory and dysmotility signs besides IEB modification.


Subject(s)
Enteric Nervous System , Parkinson Disease , Animals , Disease Models, Animal , Enteric Nervous System/metabolism , Inflammation/metabolism , Male , Mice , Neuroglia/metabolism , Occludin/metabolism , Oxidopamine/metabolism , Oxidopamine/toxicity , Parkinson Disease/metabolism
8.
Microb Pathog ; 164: 105413, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35066070

ABSTRACT

Candida albicans is one of the major pathogens found in superficial and invasive infections. This fungus expresses several virulence factors and fitness attributes that are essential to the pathogenesis. In our previous study using a murine model of serial systemic candidiasis, virulence of the recovered C. albicans was enhanced and several virulence factors were also modified after five successive passages through mice (P1-P5). In this study, we aimed to correlate the different fungal morphologies, as well as the filamentation, invasion, and stress resistance abilities, of the cells recovered after passing through this model of infection with our previous findings regarding virulence. We obtained two colony morphology types from the recovered cells, differing in their peripheral filamentation. The morphotype 1, which presented zero to five filaments in the colony edge, was higher in P2, while morphotype 2, which presented more than five filaments in the colony edge, was predominant from P3 to P5. In general, morphotype 1 showed similar levels regarding filamentation in serum, invasion of agar and cells, and resistance to osmotic, oxidative, and thermal stress in all passages analyzed. The morphotype 2, however, exhibited an enhancement in these abilities over the passages. We observed an accordance with the increased virulence over the passages obtained in our previous study and the increased adaptability profile of morphotype 2. Therefore, we suggest that the behavior observed previously in the pathogenesis and virulence could be attributed, at least in part, to the greater presence and ability of morphotype 2.


Subject(s)
Candida albicans , Candidiasis , Animals , Candidiasis/microbiology , Fungal Proteins , Mice , Virulence , Virulence Factors
9.
Animals (Basel) ; 12(2)2022 Jan 17.
Article in English | MEDLINE | ID: mdl-35049838

ABSTRACT

Preventative measures, such as biosecurity and vaccinations, are essential but not sufficient to ensure high standards of health in pig production systems. Restrictive, barren housing and many widely used management practices that cause pain and stress predispose high-performance pigs reared in intensive systems to disease. In this context, antibiotics are used as part of the infrastructure that sustains health and high levels of production in pig farms. Antimicrobial resistance (AMR) is a global emergency affecting human and animal health, and the use of antibiotics (AMU) in intensive livestock farming is considered an important risk factor for the emergence and spread of resistant bacteria from animals to humans. Tackling the issue of AMR demands profound changes in AMU, e.g., reducing their use for prophylaxis and ending it for growth promotion. In support of such recommendations, we revise the link between animal welfare and AMU and argue that it is crucial to sustainably reduce AMU while ensuring that pigs can live happy lives. In support of such recommendations, we aimed to revise the link between animal welfare and AMU in pigs by analysing stress factors related to housing and management and their impact on pig welfare. In particular, we reviewed critical management practices that increase stress and, therefore, pigs' susceptibility to disease and reduce the quality of life of pigs. We also reviewed some alternatives that can be adopted in pig farms to improve animal welfare and that go beyond the reduction in stress. By minimising environmental and management stressors, pigs can become more immunocompetent and prepared to overcome pathogenic challenges. This outcome can contribute to reducing AMU and the risk of AMR while simultaneously improving the quality of life of pigs and, ultimately, maintaining the pig industry's social license.

10.
Biomedicines ; 9(7)2021 Jul 02.
Article in English | MEDLINE | ID: mdl-34356833

ABSTRACT

Anemia is a common feature of chronic kidney disease (CKD). It is a process related to erythropoietin deficiency, shortened erythrocyte survival, uremic erythropoiesis inhibitors, and disordered iron homeostasis. Animal models of CKD-induced anemia are missing and would be desirable in order to study anemia mechanisms and facilitate the development of novel therapeutic tools. We induced three different models of CKD in mice and evaluated the development of anemia characteristics. Mice were subjected to unilateral ischemia-reperfusion or received repeated low doses of cisplatin or folic acid to induce nephropathy. Renal function, kidney injury and fibrotic markers were measured to confirm CKD. Moreover, serum hemoglobin, ferritin and erythropoietin were analyzed. Renal mRNA levels of HIF-2α, erythropoietin, hepcidin, GATA-2, and GATA-2 target genes were also determined. All three CKD models presented increased levels of creatinine, urea, and proteinuria. Renal up-regulation of NGAL, KIM-1, and TNF-α mRNA levels was observed. Moreover, the three CKD models developed fibrosis and presented increased fibrotic markers and α-SMA protein levels. CKD induced decreased hemoglobin and ferritin levels and increased erythropoietin levels in the serum. Renal tissue showed decreased erythropoietin and HIF-2α mRNA levels, while an increase in the iron metabolism regulator hepcidin was observed. GATA-2 transcription factor (erythropoietin repressor) mRNA levels were increased in all CKD models, as well as its target genes. We established three models of CKD-induced anemia, regardless of the mechanism and severity of kidney injury.

11.
Epidemics ; 37: 100491, 2021 12.
Article in English | MEDLINE | ID: mdl-34454353

ABSTRACT

INTRODUCTION: Zika virus (ZIKV) is primarily transmitted byAedes aegypti and Aedes albopictus mosquitoes between humans and non-human primates. Climate change may enhance virus reproduction in Aedes spp. mosquito populations, resulting in intensified ZIKV outbreaks. The study objective was to explore how an outbreak similar to the 2016 ZIKV outbreak in Brazil might unfold with projected climate change. METHODS: A compartmental infectious disease model that included compartments for humans and mosquitoes was developed to fit the 2016 ZIKV outbreak data from Brazil using least squares optimization. To explore the impact of climate change, published polynomial relationships between temperature and temperature-sensitive mosquito population and virus transmission parameters (mosquito mortality, development rate, and ZIKV extrinsic incubation period) were used. Projections for future outbreaks were obtained by simulating transmission with effects of projected average monthly temperatures on temperature-sensitive model parameters at each of three future time periods: 2011-2040, 2041-2070, and 2071-2100. The projected future climate was obtained from an ensemble of regional climate models (RCMs) obtained from the Co-Ordinated Regional Downscaling Experiment (CORDEX) that used Representative Concentration Pathways (RCP) with two radiative forcing values, RCP4.5 and RCP8.5. A sensitivity analysis was performed to explore the impact of temperature-dependent parameters on the model outcomes. RESULTS: Climate change scenarios impacted the model outcomes, including the peak clinical case incidence, cumulative clinical case incidence, time to peak incidence, and the duration of the ZIKV outbreak. Comparing 2070-2100 to 2016, using RCP4.5, the peak incidence was 22,030 compared to 10,473; the time to epidemic peak was 12 compared to 9 weeks, and the outbreak duration was 52 compared to 41 weeks. Comparing 2070-2100 to 2016, using RCP8.5, the peak incidence was 21,786 compared to 10,473; the time to epidemic peak was 11 compared to 9 weeks, and the outbreak duration was 50 compared to 41weeks. The increases are due to optimal climate conditions for mosquitoes, with the mean temperature reaching 28 °C in the warmest months. Under a high emission scenario (RCP8.5), mean temperatures extend above optimal for mosquito survival in the warmest months. CONCLUSION: Outbreaks of ZIKV in locations similar to Brazil are expected to be more intense with a warming climate. As climate change impacts are becoming increasingly apparent on human health, it is important to quantify the effect and use this knowledge to inform decisions on prevention and control strategies.


Subject(s)
Aedes , Zika Virus Infection , Zika Virus , Animals , Brazil/epidemiology , Disease Outbreaks , Mosquito Vectors , Zika Virus Infection/epidemiology
12.
Med Biol Eng Comput ; 59(9): 1735-1749, 2021 Sep.
Article in English | MEDLINE | ID: mdl-34297299

ABSTRACT

Parkinson's disease (PD) is a neurodegenerative disease currently diagnosed based on characteristic motor dysfunctions. The most common Parkinson's disease animal model induces massive nigrostriatal degeneration by intracerebral infusion of 6-hydroxydopamine (6-OHDA). Motor deficits in rat models of Parkinson's disease were previously addressed in other works. However, an accurate quantification of muscle function in freely moving PD-lesioned rats over time has not been described until now. In this work, we address the muscular activity characterization of a 6-OHDA-lesion model of PD along 6 weeks post-lesion based on spectral and morphological analysis of the signals. Using chronic implanted EMG electrodes in a hindlimb muscle of freely moving rats, we have evaluated the effect of the PD neurotoxic model in the muscular activity during locomotion. EMG signals obtained from animals with different time post-injury were analyzed. Power spectral densities were characterized by the mean and median frequency, and the EMG burst stationarity was previously verified for all animals. Our results show that as the time post-lesion increases both frequency parameters decrease. Probability distribution function analysis was also performed. The results suggest that contractile dynamics of the biceps femoris muscle change with time post-lesion. We have also demonstrated here the usefulness of frequency parameters as biomarkers for monitoring the muscular function changes that could be used for early detection of motor dysfunction.


Subject(s)
Neurodegenerative Diseases , Parkinson Disease , Animals , Biomarkers , Disease Models, Animal , Muscles , Rats
13.
Infect Dis Model ; 6: 664-677, 2021.
Article in English | MEDLINE | ID: mdl-33997536

ABSTRACT

INTRODUCTION: Yellow fever (YF) is primarily transmitted by Haemagogus species of mosquitoes. Under climate change, mosquitoes and the pathogens that they carry are expected to develop faster, potentially impacting the case count and duration of YF outbreaks. The aim of this study was to determine how YF virus outbreaks in Brazil may change under future climate, using ensemble simulations from regional climate models under RCP4.5 and RCP8.5 scenarios for three time periods: 2011-2040 (short-term), 2041-2070 (mid-term), and 2071-2100 (long-term). METHODS: A compartmental model was developed to fit the 2017/18 YF outbreak data in Brazil using least squares optimization. To explore the impact of climate change, temperature-sensitive mosquito parameters were set to change over projected time periods using polynomial equations fitted to their relationship with temperature according to the average temperature for years 2011-2040, 2041-2070, and 2071-2100 for climate change scenarios using RCP4.5 and RCP8.5, where RCP4.5/RCP8.5 corresponds to intermediate/high radiative forcing values and to moderate/higher warming trends. A sensitivity analysis was conducted to determine how the temperature-sensitive parameters impacted model results, and to determine how vaccination could play a role in reducing YF in Brazil. RESULTS: Yellow fever case projections for Brazil from the models varied when climate change scenarios were applied, including the peak clinical case incidence, cumulative clinical case incidence, time to peak incidence, and the outbreak duration. Overall, a decrease in YF cases and outbreak duration was observed. Comparing the observed incidence in 2017/18 to the projected incidence in 2070-2100, for RCP4.5, the cumulative case incidence decreased from 184 to 161, and the outbreak duration decreased from 21 to 20 weeks. For RCP8.5, the peak case incidence decreased from 184 to 147, and the outbreak duration decreased from 21 to 17 weeks. The observed decrease was primarily due to temperature increasing beyond that suitable for Haemagogus mosquito survival. CONCLUSIONS: Climate change is anticipated to have an impact on mosquito-borne diseases. We found outbreaks of YF may reduce in intensity as temperatures increase in Brazil; however, temperature is not the only factor involved with disease transmission. Other factors must be explored to determine the attributable impact of climate change on mosquito-borne diseases.

14.
BMC Neurosci ; 22(1): 14, 2021 03 02.
Article in English | MEDLINE | ID: mdl-33653273

ABSTRACT

BACKGROUND: Alzheimer's disease (AD) is characterized by cognitive impairment that eventually develops into dementia. Amyloid-beta (Aß) accumulation is a widely described hallmark in AD, and has been reported to cause olfactory dysfunction, a condition considered an early marker of the disease associated with injuries in the olfactory bulb (OB), the hippocampus (HIPP) and other odor-related cortexes. Adiponectin (APN) is an adipokine with neuroprotective effects. Studies have demonstrated that APN administration decreases Aß neurotoxicity and Tau hyperphosphorylation in the HIPP, reducing cognitive impairment. However, there are no studies regarding the neuroprotective effects of APN in the olfactory dysfunction observed in the Aß rat model. The aim of the present study is to determine whether the intracerebroventricular (i.c.v) administration of APN prevents the early olfactory dysfunction in an i.c.v Amyloid-beta1-42 (Aß1-42) rat model. Hence, we evaluated olfactory function by using a battery of olfactory tests aimed to assess olfactory memory, discrimination and detection in the Aß rat model treated with APN. In addition, we determined the number of cells expressing the neuronal nuclei (NeuN), as well as the number of microglial cells by using the ionized calcium-binding adapter molecule 1 (Iba-1) marker in the OB and, CA1, CA3, hilus and dentate gyrus (DG) in the HIPP. Finally, we determined Arginase-1 expression in both nuclei through Western blot. RESULTS: We observed that the i.c.v injection of Aß decreased olfactory function, which was prevented by the i.c.v administration of APN. In accordance with the olfactory impairment observed in i.c.v Aß-treated rats, we observed a decrease in NeuN expressing cells in the glomerular layer of the OB, which was also prevented with the i.c.v APN. Furthermore, we observed an increase of Iba-1 cells in CA1, and DG in the HIPP of the Aß rats, which was prevented by the APN treatment. CONCLUSION: The present study describes the olfactory impairment of Aß treated rats and evidences the protective role that APN plays in the brain, by preventing the olfactory impairment induced by Aß1-42. These results may lead to APN-based pharmacological therapies aimed to ameliorate AD neurotoxic effects.


Subject(s)
Adiponectin/pharmacology , Alzheimer Disease , Brain/drug effects , Neuroprotective Agents/pharmacology , Olfaction Disorders , Amyloid beta-Peptides/toxicity , Animals , Disease Models, Animal , Injections, Intraventricular , Male , Olfaction Disorders/etiology , Rats , Rats, Wistar
15.
J Ocul Pharmacol Ther ; 37(5): 290-300, 2021 06.
Article in English | MEDLINE | ID: mdl-33761287

ABSTRACT

Purpose: This study investigated the safety and therapeutic efficacy of licarin A (LCA) in the treatment of intraocular inflammation. Methods:In vitro safety of LCA in retinal pigmented epithelial cells (ARPE-19) and human embryonic stem cell derived-retinal pigmented epithelial cells (hES-RPE) was evaluated using CellTiter-Blue® kit. The chorioallantoic membrane (CAM) assay was used to investigate LCA safety and antiangiogenic activity. In vivo safety of intravitreal LCA was accomplished by clinical examination (including assessment of intraocular pressure), electroretinography (ERG), and histopathology. Uveitis was induced in rats by subcutaneous and intravitreal injection of bacillus Calmette-Guérin (BCG) antigen of Mycobacterium bovis. Intraocular inflammation was graded by slit-lamp and fundus examination, ERG, and histopathology. Results: LCA was safe to cells and to the CAM at concentration below 12.0 µM. LCA significantly reduced the percentage of blood vessels in the CAM. Retinal safety and anti-inflammatory efficacy of intravitreal injection of LCA 6.0 µM were confirmed through clinical, functional, and histopathological evaluation. Significant reduction of inflammatory cytokines (tumor necrosis factor-α and interleukin-6) was also found, when compared to untreated animals. Conclusion: The results suggest that LCA is a potential new drug for the treatment of inflammatory eye disease.


Subject(s)
Angiogenesis Inhibitors/pharmacology , Inflammation/drug therapy , Lignans/pharmacology , Retinal Pigment Epithelium/drug effects , Angiogenesis Inhibitors/administration & dosage , Angiogenesis Inhibitors/therapeutic use , Animals , Anti-Inflammatory Agents/pharmacology , Chorioallantoic Membrane/metabolism , Disease Models, Animal , Drug Discovery , Electroretinography/methods , Eye Diseases/pathology , Inflammation/diagnosis , Intraocular Pressure/drug effects , Intravitreal Injections , Lignans/administration & dosage , Lignans/therapeutic use , Male , Rats , Rats, Wistar , Retinal Pigment Epithelium/cytology , Retinal Pigment Epithelium/embryology , Safety , Treatment Outcome , Uveitis/chemically induced , Uveitis/pathology
16.
Vaccine ; 39(1): 158-166, 2021 01 03.
Article in English | MEDLINE | ID: mdl-33303183

ABSTRACT

BACKGROUND: This paper compares cost-effectiveness results from two models of maternal immunization to prevent pertussis in infants in Brazil, one static, one dynamic, to explore when static models are adequate for public health decisions and when the extra effort required by dynamic models is worthwhile. METHODS: We defined two scenarios to explore key differences between static and dynamic models, herd immunity and time horizon. Scenario 1 evaluates the incremental cost/DALY of maternal acellular pertussis (aP) immunization as routine infant vaccination coverage ranges from low/moderate up to, and above, the threshold at which herd immunity begins to eliminate pertussis. Scenario 2 compares cost-effectiveness estimates over the models' different time horizons. Maternal vaccine prices of $9.55/dose (base case) and $1/dose were evaluated. RESULTS: The dynamic model shows that maternal immunization could be cost-saving as well as life-saving at low levels of infant vaccination coverage. When infant coverage reaches the threshold range (90-95%), it is expensive: the dynamic model estimates that maternal immunization costs $2 million/DALY at infant coverage > 95% and maternal vaccine price of $9.55/dose; at $1/dose, cost/DALY is $200,000. By contrast, the static model estimates costs/DALY only modestly higher at high than at low infant coverage. When the models' estimates over their different time horizons are compared at infant coverage < 90-95%, their projections fall in the same range. CONCLUSIONS: Static models may serve to explore an intervention's cost-effectiveness against infectious disease: the direction and principal drivers of change were the same in both models. When, however, an intervention too small to have significant herd immunity effects itself, such as maternal aP immunization, takes place against a background of vaccination in the rest of the population, a dynamic model is crucial to accurate estimates of cost-effectiveness. This finding is particularly important in the context of widely varying routine infant vaccination rates globally. CLINICAL TRIAL REGISTRY: Clinical Trial registry name and registration number: Not applicable.


Subject(s)
Whooping Cough , Brazil , Cost-Benefit Analysis , Humans , Immunization , Immunization Programs , Infant , Pertussis Vaccine , Vaccination , Whooping Cough/prevention & control
17.
Neurotoxicology ; 82: 18-25, 2021 01.
Article in English | MEDLINE | ID: mdl-33127410

ABSTRACT

1-Methyl-4-phenylpyridinium ion (MPP+)-induced neurotoxicity produces cellular damage resembling that encountered in Parkinson's disease. The mechanisms of cellular death after MPP+ include the participation of oxidative stress in the loss of dopaminergic neurons. Among the mechanisms of defense against oxidative stress, several copper-dependent proteins have been implicated: Cu/Zn-SOD, ceruloplasmin, and metallothionein. Another important mechanism of damage, is MPP + interference with mitochondrial respiration. Both, oxidative stress and inhibition of mitochondrial respiration may trigger apoptosis in the neurons after MPP+. The aim of the present study was to characterize the time-course of apoptosis induced by MPP+ to determine if copper sulfate pretreatment is able to prevent the activation of caspases and decreased the neuronal apoptosis. MPP+ was microinjected into rat striatum using a stereotactic frame. The results showed increased activities of caspases 8, 9 and 3, between 72-120 hours after administration of MPP+, both in striatum and midbrain. After this study, we tested the effect of CuSO4 on MPP+ neurotoxicity, showing a diminution of the apoptotic damage induced by MPP+, decreased levels of enzymatic activity of caspases: 8 (-34 and -25 %), 9 (-25 and -42 %) and 3 (-40 and -29 %) in striatum and midbrain, respectively. Finally, we performed an immunohistochemical analysis, evidencing a decreased number of apoptotic cells in the groups pretreated with copper sulfate pretreatment compared to the control group. With these findings, it is concluded that pretreatment with copper sulfate may be a good alternative to prevent MPP+-induced apoptosis.


Subject(s)
1-Methyl-4-phenylpyridinium/toxicity , Apoptosis/drug effects , Copper Sulfate/pharmacology , Corpus Striatum/drug effects , Mesencephalon/drug effects , 1-Methyl-4-phenylpyridinium/antagonists & inhibitors , Animals , Annexin A5/metabolism , Caspase 3/metabolism , Caspase 8/metabolism , Caspase 9/metabolism , In Situ Nick-End Labeling , Male , Rats , Rats, Wistar
18.
Araçatuba; s.n; 2019. 80 p. ilus, tab.
Thesis in English | LILACS, BBO - Dentistry | ID: biblio-1051385

ABSTRACT

O presente estudo avaliou pela primeira vez "in vivo" os efeitos de três concentrações do butyl azul de toluidina (BuTB) como agente fotossensibilizador na terapia fotodinâmica antimicrobiana (aPDT), como terapia coadjuvante a raspagem e alisamento radicular (RAR), para o tratamento de periodontite experimental (PE) em ratos. A PE foi induzida por meio da instalação de um fio de algodão ao redor do primeiro molar inferior esquerdo. Posteriormente os animais foram aleatoriamente distribuídos em 7 grupos com 15 animais cada, através de uma tabela gerada por computador, de acordo com os seguintes tratamentos: RAR (n=15) - RAR seguido de irrigação local de solução salina fisiológica; BuTB-0,1 (n=15) - RAR seguido de aplicação local de BuTB na concentração de 0,1 mg/mL; aPDT-0,1 (n=15) - RAR seguido da aplicação local de BuTB na concentração de 0,1 mg/mL e irradiação com laser de diodo (LD) de InGaAlP (660 nm, 40 mW, 60 s, 2,4 J); BuTB-0,5 (n=15) ­ RAR seguido de aplicação local de BuTB na concentração de 0,5 mg/mL; aPDT-0,5 (n=15) ­ RAR seguido da aplicação local de BuTB na concentração de 0,5 mg/mL e irradiação com LD; BuTB-2,0 (n=15) - RAR seguido de aplicação local de BuTB na concentração de 2 mg/mL; aPDT-2,0 (n=15) - RAR seguido da aplicação local de BuTB na concentração de 2 mg/mL e irradiação com LD. Decorridos 7, 15 e 30 dias pós-tratamento, 5 animais de cada grupo foram submetidos à eutanásia. A área de furca dos molares foi submetida às análises histológica, histométrica e dos padrões de imunomarcação para TGF-ß1, OCN e TRAP. Os dados foram submetidos à análise estatística (α = 5%). De acordo com a análise histométrica na região de furca, todos os grupos experimentais apresentaram menor perda óssea comparado ao grupo controle. Histologicamente, os espécimes do aPDT-0,5 apresentaram uma resposta inflamatória local mais branda e menos extensa, com melhor reestruturação tecidual em todos os períodos. Aos 30 dias observou-se resolução total da resposta inflamatória local, com presença de tecido conjuntivo denso. Alguns espécimes apresentavam trabéculas ósseas com contorno regular revestido com osteoblastos ativos, incluindo áreas de neoformação óssea. O tratamento com aPDT na concentração de 0,5 mg/mL resultou em padrões mais altos de imunomarcação de TGF-ß1 em todos os períodos e de OCN aos 30 dias. Diante dos resultados obtidos, todas as concentrações do novo fotossensibilizador BuTB trouxeram resultados adicionais ao tratamento da PE em relação a RAR. No entanto, a aPDT realizada com a concentração de 0,5 mg/mL resultou em benefícios adicionais na resposta inflamatória local e melhor reestruturação tecidual(AU)


The present study evaluated for the first time the effects of three concentrations of butyl toluidine blue (BuTB) as a photosensitizing agent on antimicrobial photodynamic therapy (aPDT), as adjuvant therapy to scaling and root planing (SRP), for the treatment of experimental periodontitis (EP) in rats. EP was induced by placing a cotton thread around the lower left first molar. Subsequently, the animals were randomly distributed into seven groups with 15 animals each, through a computer generated table, according to the following treatments: SRP (n = 15), SRP followed by local irrigation of physiological saline solution; BuTB-0.1 (n = 15), SRP followed by local application of 0.1 mg/mL BuTB; aPDT-0.1 (n = 15), SRP followed by local application of BuTB at 0.1 mg/mL concentration and irradiation with InGaAlP diode laser (DL) (660 nm, 40 mW, 60 s, 4 J); BuTB-0.5 (n = 15), SRP followed by local application of BuTB at 0.5 mg/mL concentration; aPDT-0.5 (n = 15), SRP followed by local application of BuTB at 0.5 mg/mL concentration and DL irradiation; BuTB-2.0 (n = 15), SRP followed by local application of BuTB at 2 mg/mL concentration; aPDT-2.0 (n = 15), SRP followed by local application of BuTB at 2 mg/mL concentration and DL irradiation. The animals (n=5) from each group were submitted to euthanasia at 7, 15 and 30 days post-treatment. The furcation area of the first lower molar was submitted to histological, histometric and immunohistochemical analyses to identify TGF-ß1, OCN and TRAP. The data were submitted to statistical analysis (α = 5%). According to the histometric analysis in the furcation region, all experimental groups presented lower bone loss compared to the control group. Histologically, the aPDT -0.5 specimens presented a milder and less extensive local inflammatory response, with better tissue remodeling in all periods. Total resolution of the local inflammatory response was observed at 30 days with presence of mature connective tissue. Some specimens presented bone trabeculae with a regular contour and active osteoblasts, including areas of bone neoformation. Treatment with aPDT-0.5 also resulted in higher immunolabelling patterns of TGFß1 at all periods and of OCN at 30 days. All concentrations of the new photosensitizer BuTB resulted in significant improvement for EP treatment in relation to SRP. However, aPDT combined with BuTB at 0.5 mg / mL showed the best benefits for inflammatory response and periodontal repair process(AU)


Subject(s)
Animals , Rats , Periodontitis , Photochemotherapy , Dental Scaling , Periodontitis/drug therapy , Rats, Wistar , Photosensitizing Agents
19.
Behav Sci (Basel) ; 8(10)2018 Sep 20.
Article in English | MEDLINE | ID: mdl-30241338

ABSTRACT

Huntington's disease (HD) is an inherited, neurodegenerative disorder that results from the degeneration of striatal neurons, mainly GABAergic neurons. The study of neurochemical activity has provided reliable markers to explain motor disorders. To treat neurodegenerative diseases, stem cell transplants with bone marrow (BM) have been performed for several decades. In this work we determine the effect of mononuclear bone marrow cell (mBMC) transplantation on the rotational behavior and neurochemical activity in a model of Huntington's disease in rats. Four experimental groups were organized: Group I: Control animals (n = 5); Group II: Lesion with quinolinic acid (QA) in the striatum (n = 5); Group III: Lesion with QA and transplant with mBMC (n = 5); Group IV: Lesion with QA and transplant with culture medium (Dulbecco's modified Eagle's medium (DMEM) injection) (n = 5). The rotational activity induced by D-amphetamine was evaluated and the concentration of the neurotransmitter amino acids (glutamate and GABA) was studied. The striatal cell transplantation decreases the rotations induced by D-amphetamine (p < 0.04, Wilcoxon matched pairs test) and improves the changes produced in the levels of neurotransmitters studied. This work suggests that the loss of GABAergic neurons in the brain of rats lesioned with AQ produces behavioral and neurochemical alterations that can be reversed with the use of bone marrow mononuclear cell transplants.

20.
mSphere ; 3(4)2018 08 29.
Article in English | MEDLINE | ID: mdl-30158282

ABSTRACT

White-nose syndrome (WNS) is causing significant declines in populations of North American hibernating bats, and recent western and southern expansions of the disease have placed additional species at risk. Understanding differences in species susceptibility and identifying management actions to reduce mortality of bats from WNS are top research priorities. However, the use of wild-caught susceptible bats, such as Myotis lucifugus, as model species for WNS research is problematic and places additional pressure on remnant populations. We investigated the feasibility of using Tadarida brasiliensis, a highly abundant species of bat that tolerates captivity, as the basis for an experimental animal model for WNS. Using methods previously established to confirm the etiology of WNS in M. lucifugus, we experimentally infected 11 T. brasiliensis bats with Pseudogymnoascus destructans in the laboratory under conditions that induced hibernation. We detected P. destructans on all 11 experimentally infected bats, 7 of which exhibited localized proliferation of hyphae within the epidermis, dermis, and subcutaneous tissue, similar to invasive cutaneous ascomycosis observed in M. lucifugus bats with WNS. However, the distribution of lesions across wing membranes of T. brasiliensis bats was limited, and only one discrete "cupping erosion," diagnostic for WNS, was identified. Thus, the rarity of lesions definitive for WNS suggests that T. brasiliensis does not likely represent an appropriate model for studying the pathophysiology of this disease. Nonetheless, the results of this study prompt questions concerning the potential for free-ranging, migratory T. brasiliensis bats to become infected with P. destructans and move the fungal pathogen between roost sites used by species susceptible to WNS.IMPORTANCE White-nose syndrome (WNS) is a fungal disease that is causing severe declines of bat populations in North America. Identifying ways to reduce the impacts of this disease is a priority but is inhibited by the lack of an experimental animal model that does not require the use of wild-caught bat species already impacted by WNS. We tested whether Tadarida brasiliensis, one of the most abundant species of bats in the Americas, could serve as a suitable animal model for WNS research. While T. brasiliensis bats were susceptible to experimental infection with the fungus under conditions that induced hibernation, the species exhibited limited pathology diagnostic for WNS. These results indicate that T. brasiliensis is not likely a suitable experimental model for WNS research. However, the recovery of viable WNS-causing fungus from experimentally infected bats indicates a potential for this species to contribute to the spread of the pathogen where it coexists with other species of bats affected by WNS.


Subject(s)
Ascomycota/isolation & purification , Chiroptera/microbiology , Dermatomycoses/veterinary , Nose , Animals , Ascomycota/pathogenicity , Dermatomycoses/pathology , Hibernation , Male , North America , Species Specificity
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