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1.
BMC Biol ; 21(1): 66, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-37013555

RESUMO

BACKGROUND: Guanine crystals are organic biogenic crystals found in many organisms. Due to their exceptionally high refractive index, they contribute to structural color and are responsible for the reflective effect in the skin and visual organs in animals such as fish, reptiles, and spiders. Occurrence of these crystals in animals has been known for many years, and they have also been observed in eukaryotic microorganisms, but not in prokaryotes. RESULTS: In this work, we report the discovery of extracellular crystals formed by bacteria and reveal that they are composed of guanine monohydrate. This composition differs from that of biogenic guanine crystals found in other organisms, mostly composed of ß anhydrous guanine. We demonstrate the formation of these crystals by Aeromonas and other bacteria and investigate the metabolic traits related to their synthesis. In all cases studied, the presence of the bacterial guanine crystals correlates with the absence of guanine deaminase, which could lead to guanine accumulation providing the substrate for crystal formation. CONCLUSIONS: Our finding of the hitherto unknown guanine crystal occurrence in prokaryotes extends the range of organisms that produce these crystals to a new domain of life. Bacteria constitute a novel and more accessible model to study the process of guanine crystal formation and assembly. This discovery opens countless chemical and biological questions, including those about the functional and adaptive significance of their production in these microorganisms. It also paves the road for the development of simple and convenient processes to obtain biogenic guanine crystals for diverse applications.


Assuntos
Peixes , Guanina , Animais , Guanina/química , Pele , Bactérias
2.
Mol Pharm ; 20(6): 2814-2821, 2023 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-36625731

RESUMO

The objective of the project was to investigate the plausibility of active pharmaceutical ingredients (APIs) to undergo sublimation from topical application following evaporation of solvent. Topical formulations with different APIs were subjected to a sublimation screening test. The APIs in the selected topical products were found to undergo sublimation to a different extent. The salicylic acid topical product was found to undergo a significant loss due to sublimation. The extent of sublimation of salicylic acid was significantly greater at skin temperature compared to room temperature. When the APIs were subjected to the sublimation screening test in their neat form at 32 ± 1 °C, the natural log of the rate of sublimation decreased linearly with the standard enthalpy of sublimation of compound (R2 = 0.89). The formulation composition was found to have a significant impact on the extent of sublimation of the representative API, salicylic acid. The sublimation of APIs from the topical product was found to affect the mass balance studies in the case of the salicylic acid ointment. Furthermore, the results of the human studies agreed with the in vitro experimental results demonstrating the plausibility of loss of API due to sublimation from the site of application.


Assuntos
Administração Tópica , Ácido Salicílico , Sublimação Química , Humanos
3.
J Chem Phys ; 159(17)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37929867

RESUMO

In this work we implement a new methodology to study structural and mechanical properties of systems having spherical and planar symmetries throughout Molecular Dynamics simulations. This methodology is applied here to a drug delivery system based in polymersomes, as an example. The chosen model drug was the local anesthetic prilocaine due to previous parameterization within the used coarse grain scheme. In our approach, mass density profiles (MDPs) are used to obtain key structural parameters of the systems, and pressure profiles are used to estimate the curvature elastic parameters. The calculation of pressure profiles and radial MPDs required the development of specific methods, which were implemented in an in-house built version of the GROMACS 2018 code. The methodology presented in this work is applied to characterize poly(ethylene oxide)-poly(butadiene) polymersomes and bilayers loaded with the model drug prilocaine. Our results show that structural properties of the polymersome membrane could be obtained from bilayer simulations, with significantly lower computational cost compared to whole polymersome simulations, but the bilayer simulations are insufficient to get insights on their mechanical aspects, since the elastic parameters are canceled out for the complete bilayer (as consequence of the symmetry). The simulations of entire polymersomes, although more complex, offer a complementary approach to get insights on the mechanical behavior of the systems.


Assuntos
Simulação de Dinâmica Molecular , Polietilenoglicóis , Preparações Farmacêuticas , Polietilenoglicóis/química , Sistemas de Liberação de Medicamentos , Prilocaína
4.
Biodegradation ; 34(2): 181-197, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36596914

RESUMO

Polycyclic Aromatic Hydrocarbons (PAHs) impose adverse effects on the environment and human life. The use of synthetic microbial consortia is promising in bioremediation of contaminated sites with these pollutants. However, the design of consortia taking advantage of natural interactions has been poorly explored. In this study, a dual synthetic bacterial consortium (DSC_AB) was constructed with two key members (Sphingobium sp. AM and Burkholderia sp. Bk), of a natural PAH degrading consortium. DSC_AB showed significantly enhanced degradation of PAHs and toxic intermediary metabolites relative to the axenic cultures, indicating the existence of synergistic relationships. Metaproteomic and gene-expression analyses were applied to obtain a view of bacterial performance during phenanthrene removal. Overexpression of the Bk genes, naph, biph, tol and sal and the AM gene, ahdB, in DSC_AB relative to axenic cultures, demonstrated that both strains are actively participating in degradation, which gave evidence of cross-feeding. Several proteins related to stress response were under-expressed in DSC_AB relative to axenic cultures, indicating that the division of labour reduces cellular stress, increasing the efficiency of degradation. This is the one of the first works revealing bacterial relationships during PAH removal in a synthetic consortium applying an omics approach. Our findings could be used to develop criteria for evaluating the potential effectiveness of synthetic bacterial consortia in bioremediation.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes do Solo , Sphingomonadaceae , Humanos , Consórcios Microbianos/genética , Poluentes do Solo/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Biodegradação Ambiental , Perfilação da Expressão Gênica , Sphingomonadaceae/metabolismo , Microbiologia do Solo
5.
J Org Chem ; 87(20): 13480-13493, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36154121

RESUMO

The oxidative α-functionalization of 2-aryl-1,2,3,4-tetrahydroisoquinolines (THIQs) promoted by a versatile heterogeneous nanocatalyst consisting of copper nanoparticles immobilized on silica-coated maghemite (CuNPs/MagSilica) has been accomplished. The methodology was successfully applied in the cross-dehydrogenative coupling (CDC) reaction of N-aryl THIQs and other tertiary amines with nitromethane as a pro-nucleophile (aza-Henry reaction) and the α-oxidation of THIQs with O2 as a green oxidant. Phosphite, alkyne, or indole derivatives were also shown to be suitable candidates for their use as pro-nucleophiles in the CDC reaction with THIQs. The catalyst, with very low copper loading (0.4-1.0 mol % Cu), could be easily recovered by means of an external magnet and reused in four cycles without significant loss of activity.


Assuntos
Fosfitos , Tetra-Hidroisoquinolinas , Cobre , Catálise , Alcinos , Dióxido de Silício , Oxidantes , Aminas , Estresse Oxidativo , Indóis
6.
Evol Anthropol ; 31(5): 237-239, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35758530

RESUMO

In an Evolutionary Anthropology article Roksandic et al. (2022) propose a new middle Pleistocene hominin species H. bodoensis to replace a "poorly defined" Homo heidelbergenis. Homo bodoensis extends from the African Middle Pleistocene through the Levant to South-eastern Europe with all currently classified H. heidelbergensis fossils from western Europe subsumed into Homo neandertalensis. The authors claim their new species will be more clearly defined than H. heidelbergensis and will better describe hominin variation and evolution in the middle Pleistocene. Roksandic et al. are unable to account for some European fossils (i.e., Petralona and Arago) and provide no evidence as to how their new species meets their objectives. Fatally, they overlook the priority rule and fail to realize that H. bodoensis is both a junior synonym of Homo rhodesiensis and Homo saldanensis. Roksandic et al. conflate taxonomy with phylogeny, present hypotheses as facts, and harbor many systematic and evolutionary misconceptions.


Assuntos
Hominidae , Animais , Fósseis , Antropologia , Europa (Continente) , Evolução Biológica
7.
BMC Psychiatry ; 22(1): 537, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35941557

RESUMO

BACKGROUND: Emotional and stress-related disorders show high incidence, prevalence, morbidity, and comorbidity rates in Mexico. In recent decades, research findings indicate that cognitive behavioral interventions, from a disorder-specific perspective, are the effective front-line treatment for anxiety and depression care. However, these treatments are not often used. Reasons include limited access and low availability to effective interventions and comorbidity between mental disorders. Emotional deregulation of negative affectivity has been found to be a mediating factor in addressing emotional disorders from a transdiagnostic perspective, aimed at two or more specific disorders. In addition, technological advancement has created alternatives for psychological assistance, highlighting the possibilities offered by technologies since Internet-supported intervention programs have been empirically tested for effectiveness, efficiency and efficacy and can be key to ensuring access to those who are inaccessible. The aim of the study is to evaluate the efficacy, moderators of clinical change and acceptability of a transdiagnostic guided Internet-delivered intervention versus a transdiagnostic self-guided Internet-delivered intervention for emotional, trauma and stress-related disorders, and waiting list in community sample. METHODS: A three-armed, parallel group, superiority randomized controlled clinical trial with repeated measurements at four times: pretest, posttest, follow-up at 3, 6 and 12 months. Outcomes assessor, participant, care provider and investigator will be blinded. Participants aged 18 to 70 years will be randomly allocated 1:1:1 to one of three study arms: a) Transdiagnostic guided internet-delivered intervention with synchronous assistance, b) Transdiagnostic self-guided internet-delivered intervention, c) Waiting list group. Based on sample size estimation, a minimum of 207 participants (69 in each intervention group) will be included. DISCUSSION: The study could contribute to improving the efficacy of transdiagnostic internet-delivered interventions to promote the dissemination of evidence-based treatments and eventually, to decrease the high prevalence of emotional and trauma-related disorders in the Mexican population. TRIAL REGISTRATION: ClinicalTrial.gov: NCT05225701 . Registered February 4, 2022.


Assuntos
Terapia Cognitivo-Comportamental , Terapia Assistida por Computador , Transtornos de Ansiedade/diagnóstico , Transtornos de Ansiedade/terapia , Terapia Cognitivo-Comportamental/métodos , Humanos , Internet , México , Ensaios Clínicos Controlados Aleatórios como Assunto , Terapia Assistida por Computador/métodos , Resultado do Tratamento
8.
Actas Dermosifiliogr ; 113(10): 923-929, 2022.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-35636506

RESUMO

BACKGROUND: The diagnosis of Neurofibromatosis type 1 (NF1) is usually delayed in children without a family history. We aimed to define the prevalence and characteristics of prevalent skin manifestations in NF1 compared to the general population, which continue to be excluded from the diagnostic criteria for NF1. PATIENTS AND METHODS: Case-control study, matched by age groups, in which 108 patients with a diagnosis of NF1 and 137 healthy controls were included. RESULTS: The prevalence of nevus anemicus (NA) (p<0.001) and juvenile xanthogranulomas (JXG) (p<0.001) was significantly higher in the population affected by NF1 than in the control population. A specificity of 99.27% [confidence interval (CI): 95.4-99.96%] and a positive predictive value (PPV) of 98.80% [92.54-99.94%] were estimated for NA and a specificity of 99.27% [95.4-99.96%] and a PPV of 92.86% [64.17-99.63%] for JXG in the diagnosis of NF1 in children who present 6 or more Café-au-lait macules. Statistically significant differences were also evidenced in the distribution by phototypes (p 0.025) and in relation to generalized itching with no other cause (p<0.001). CONCLUSIONS: NA and JXG are relevant clinical findings for the diagnosis of NF1, especially during the first years of life. We consider that its inclusion among the diagnostic criteria of the disease should be evaluated.


Assuntos
Neurofibromatose 1 , Transtornos da Pigmentação , Xantogranuloma Juvenil , Criança , Humanos , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/epidemiologia , Estudos de Casos e Controles , Manchas Café com Leite/epidemiologia , Manchas Café com Leite/etiologia , Manchas Café com Leite/diagnóstico , Prevalência , Inflamação
9.
Actas Dermosifiliogr ; 113(10): T923-T929, 2022.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-36162491

RESUMO

BACKGROUND: The diagnosis of Neurofibromatosis type 1 (NF1) is usually delayed in children without a family history. We aimed to define the prevalence and characteristics of prevalent skin manifestations in NF1 compared to the general population, which continue to be excluded from the diagnostic criteria for NF1. PATIENTS AND METHODS: Case-control study, matched by age groups, in which 108 patients with a diagnosis of NF1 and 137 healthy controls were included. RESULTS: The prevalence of nevus anemicus (NA) (P<.001) and juvenile xanthogranulomas (JXG) (P<.001) was significantly higher in the population affected by NF1 than in the control population. A specificity of 99.27% (confidence interval): 95.4-99.96%] and a positive predictive value (PPV) of 98.80% [92.54-99.94%] were estimated for NA and a specificity of 99.27% [95.4-99.96%] and a PPV of 92.86% [64.17-99.63%] for JXG in the diagnosis of NF1 in children who present 6 or more Café-au-lait macules. Statistically significant differences were also evidenced in the distribution by phototypes (P=.025) and in relation to generalized itching with no other cause (P<.001). CONCLUSIONS: NA and JXG are relevant clinical findings for the diagnosis of NF1, especially during the first years of life. We consider that its inclusion among the diagnostic criteria of the disease should be evaluated.


Assuntos
Neurofibromatose 1 , Transtornos da Pigmentação , Xantogranuloma Juvenil , Criança , Humanos , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/epidemiologia , Estudos de Casos e Controles , Manchas Café com Leite/diagnóstico , Prevalência , Inflamação
10.
Ann Oncol ; 32(7): 881-895, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33894335

RESUMO

BACKGROUND: In the phase III KEYNOTE-189 study (NCT02578680), pembrolizumab plus pemetrexed and platinum-based chemotherapy (pemetrexed-platinum) significantly improved overall survival (OS) and progression-free survival (PFS) in patients with previously untreated metastatic nonsquamous non-small-cell lung cancer (NSCLC) versus placebo plus pemetrexed-platinum. We report updated efficacy outcomes from the protocol-specified final analysis, including outcomes in patients who crossed over to pembrolizumab from pemetrexed-platinum and in patients who completed 35 cycles (∼2 years) of pembrolizumab. PATIENTS AND METHODS: Eligible patients were randomized 2 : 1 to receive pembrolizumab 200 mg (n = 410) or placebo (n = 206) every 3 weeks (for up to 35 cycles, ∼2 years) plus four cycles of pemetrexed (500 mg/m2) and investigators' choice of cisplatin (75 mg/m2) or carboplatin (area under the curve 5 mg·min/ml) every 3 weeks, followed by pemetrexed until progression. Patients assigned to placebo plus pemetrexed-platinum could cross over to pembrolizumab upon progression if eligibility criteria were met. The primary endpoints were OS and PFS. RESULTS: After a median follow-up of 31.0 months, pembrolizumab plus pemetrexed-platinum continued to improve OS [hazard ratio (HR), 0.56; 95% confidence interval (CI), 0.46-0.69] and PFS (HR, 0.49; 95% CI, 0.41-0.59) over placebo plus pemetrexed-platinum regardless of programmed death-ligand 1 expression. Objective response rate (ORR) (48.3% versus 19.9%) and time to second/subsequent tumor progression on next-line treatment (PFS2; HR, 0.50; 95% CI, 0.41-0.61) were improved in patients who received pembrolizumab plus pemetrexed-platinum. Eighty-four patients (40.8%) from the placebo plus pemetrexed-platinum group crossed over to pembrolizumab on-study. Grade 3-5 adverse events occurred in 72.1% of patients receiving pembrolizumab plus pemetrexed-platinum and 66.8% of patients receiving placebo plus pemetrexed-platinum. Fifty-six patients completed 35 cycles (∼2 years) of pembrolizumab; ORR was 85.7% and 53 (94.6%) were alive at data cut-off. CONCLUSIONS: Pembrolizumab plus pemetrexed-platinum continued to show improved efficacy outcomes compared with placebo plus pemetrexed-platinum, with manageable toxicity. These findings support first-line pembrolizumab plus pemetrexed-platinum in patients with previously untreated metastatic nonsquamous NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Anticorpos Monoclonais Humanizados , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Pemetrexede/uso terapêutico , Platina/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
11.
J Trop Pediatr ; 67(3)2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-32875334

RESUMO

The prevalence of pediculosis in Mexican children was studied in San Nicolas and Tapachula, Mexico. A cross-sectional study included 888 students between six and 12 years old from two urban communities with an unequal socioeconomic status between September 2015 and March 2016. A Pearson χ2 and multivariate logistic analysis were carried out to associate risk factors to pediculosis. The overall prevalence of pediculosis from both localities was 23.9%. The female gender; long and medium hair; living with someone infested; previously infested by head lice and curling hair were variables linked to a significantly higher prevalence of pediculosis (p < 0.01). Nevertheless, no significant differences were observed in the age groups, localities and socioeconomic status for human lice infection. Socioeconomic variables such as numbers of inhabitants, floors of house, beds and rooms; and parents' qualification did not show a significative association for pediculosis. Health education in schools is needed for pediculosis prevention and remove the stigmatization of this disease related to poverty.


Assuntos
Infestações por Piolhos , Pediculus , Animais , Criança , Estudos Transversais , Feminino , Humanos , Infestações por Piolhos/epidemiologia , México/epidemiologia , Prevalência , Classe Social , Fatores Socioeconômicos
12.
Arch Biochem Biophys ; 685: 108347, 2020 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-32194045

RESUMO

The reason that determines the pathological deposition of human apolipoprotein A-I variants inducing organ failure has been under research since the early description of natural mutations in patients. To shed light into the events associated with protein aggregation, we studied the structural perturbations that may occur in the natural variant that shows a substitution of a Leucine by an Arginine in position 60 (L60R). Circular dichroism, intrinsic fluorescence measurements, and proteolysis analysis indicated that L60R was more unstable, more sensitive to cleavage and the N-terminus was more disorganized than the protein with the native sequence (Wt). A higher tendency to aggregate was also detected when L60R was incubated at physiological pH. In addition, the small structural rearrangement observed for the freshly folded variant led to the release of tumor necrosis factor-α and interleukin-1ß from a model of macrophages. However, the mutant preserved both its dimeric conformation and its lipid-binding capacity. Our results strongly suggest that the chronic disease may be a consequence of the native conformation loss which elicits the release of protein conformations that could be either cytotoxic or precursors of amyloid conformations.


Assuntos
Proteínas Amiloidogênicas/metabolismo , Apolipoproteína A-I/metabolismo , Proteínas Amiloidogênicas/química , Proteínas Amiloidogênicas/genética , Amiloidose/etiologia , Amiloidose/genética , Apolipoproteína A-I/química , Apolipoproteína A-I/genética , Humanos , Mutação Puntual , Multimerização Proteica , Estabilidade Proteica , Estrutura Secundária de Proteína
13.
J Investig Allergol Clin Immunol ; 30(4): 264-271, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31283523

RESUMO

OBJECTIVE: To assess the main factors involved in asthma control and health-related quality of life in elderly asthmatic patients. METHODS: We performed a retrospective case-control study nested in a historical cohort that compared patients who had partly controlled or uncontrolled asthma (Asthma Control Test [ACT] score ≤19) (cases) with patients who had well-controlled asthma (ACT ≥20) (controls). Clinical data were collected from medical records. Outcomes included ACT score and health-related quality of life (Asthma-Specific Quality of Life Questionnaire [AQLQ]). Pulmonary function was determined by spirometry. RESULTS: We evaluated 209 asthma patients (151 women) aged ≥65 years. Mean age was 73.55 years. Most patients had persistent moderate (47.60%) or severe (47.12%) asthma. A total ACT score ≤19 was obtained in 64 (30.62%) patients. Lack of adherence to treatment and presence of severe exacerbations were risk factors for partly controlled/uncontrolled asthma (OR, 8.33 and 5.29, respectively). In addition, for each additional unit score in the AQLQ, the risk of poor control increased by 1.51. The factors influencing the AQLQ score were asthma control (ACT) and presence of comorbidities such as depression, gastroesophageal reflux disease, and osteoporosis. CONCLUSIONS: Despite receiving antiasthma therapy, almost one-third of elderly patients had uncontrolled asthma, possibly as a result of poor adherence, exacerbations, and reduced health-related quality of life. Nonrespiratory comorbid conditions in older patients do not seem to be associated with worse control of asthma symptoms, although their effect on health-related quality of life could indirectly affect asthma control.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Depressão/epidemiologia , Cooperação e Adesão ao Tratamento , Idoso , Idoso de 80 Anos ou mais , Asma/epidemiologia , Comorbidade , Progressão da Doença , Feminino , Humanos , Masculino , Qualidade de Vida , Fatores de Risco , Espanha/epidemiologia , Resultado do Tratamento
14.
Health Educ Res ; 35(5): 376-395, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32951047

RESUMO

Dengue virus is the main arboviral disease transmitted by Aedes mosquitoes and affects mainly school-aged children and teens. Many methods have been developed for dengue control, including health education strategies for elementary and high school students. The objective of this study is to provide an update on the status of health education on dengue in schools and provide new perspectives on health behavior research in order to reduce the proliferation of mosquitoes and spread of arboviral diseases among school-aged children and other community members. A systematic review about health educational initiatives was carried out. This research discusses the effectiveness of these strategies in educating students about dengue disease and mosquito control and how the school is relevant for community-based participation in research on dengue education. The study found that employing ludic strategies and directly involving children in mosquito control in their households have been the most attractive and effective strategies for dengue education in children and teens. However, the sustainability of protective behaviors has been poorly evaluated, and new approaches for health behavior research are needed. Inasmuch as, schools are important places for gathering community members, and students can serve as an essential link between educative interventions and the community.


Assuntos
Dengue , Adolescente , Animais , Criança , Dengue/prevenção & controle , Comportamentos Relacionados com a Saúde , Educação em Saúde , Humanos , Assunção de Riscos , Instituições Acadêmicas
15.
Trop Med Int Health ; 24(11): 1311-1319, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31483936

RESUMO

BACKGROUND: Aedes aegypti and Aedes albopictus are the main mosquito species responsible for dengue virus (DENV) transmission to humans in the tropical and subtropical regions of the world. The role of vertical transmission in the epidemiology of dengue and the maintenance of this arbovirus in nature during interepidemic periods remain poorly understood, and DENV vertical transmission could sustain the existence of virus reservoirs within Aedes populations. METHODS: Between April 2011 and October 2012, we monitored vertical transmission of DENV in Ae. aegypti and Ae. albopictus in 9 cities of 4 Mexican states. Aedes eggs were collected in ovitraps, then adults were reared under laboratory conditions and their heads were used to infect C6/36 cells. The presence of flavivirus was detected by immunofluorescence assays (IFA), and DENV infection was confirmed by RT-PCR. RESULTS: About 96% of reared adults were Ae. aegypti and 4.0% were Ae. albopictus. No infection was detected in Ae. albopictus, whereas 54 of 713 (7.8%) of Ae. aegypti pools tested positive. A minimum infection rate (MIR) of 2.52 per 1000 mosquitoes was estimated for Ae. aegypti. DENV-1, DENV-2 & DENV-3 serotypes were detected even during interepidemic periods. CONCLUSIONS: This study reports the evidence of vertical transmission of dengue virus with viral isolation and molecular confirmation in Ae. aegypti eggs collected in four endemic regions of Central and Southern Mexico. Vertical transmission may play a role as a reservoir mechanism during mosquito dormancy in interepidemic periods but with minor participation in transmission during epidemic periods.


TRANSMISSION VERTICALE DU VIRUS DE LA DENGUE CHEZ AEDES AEGYPTI ET SON RÔLE DANS LA PERSISTANCE ÉPIDÉMIOLOGIQUE DE LA DENGUE DANS LE CENTRE ET LE SUD DU MEXIQUE: OBJECTIF: Aedes aegypti et Aedes albopictus sont les principales espèces de moustiques responsables de la transmission du virus de la dengue (DENV) à l'homme dans les régions tropicales et subtropicales du monde. Le rôle de la transmission verticale dans l'épidémiologie de la dengue et le maintien de cet arbovirus dans la nature pendant les périodes d'inter-épidémiques restent mal compris, et la transmission verticale du DENV pourrait maintenir l'existence de réservoirs de virus au sein des populations d'Aedes. Notre objectif était d'évaluer la transmission verticale du DENV au Mexique. MÉTHODES: Entre avril 2011 et octobre 2012, nous avons surveillé la transmission verticale du DENV chez Ae. aegypti et Ae. albopictus dans 9 villes de 4 états mexicains. Les œufs d'Aedes ont été collectés dans des ovitraps, puis les adultes ont été élevés dans des conditions de laboratoire et leur tête a été utilisée pour infecter les cellules C6/36. La présence de flavivirus a été détectée par des tests d'immunofluorescence (IFA) et l'infection par DENV a été confirmée par RT-PCR. RÉSULTATS: 96% des adultes élevés étaient Ae. aegypti et 4,0% étaient Ae. albopictus. Aucune infection n'a été détectée chez Ae. albopictus, alors que 54 des 713 (7,8%) des pools d'Ae. aegypti ont été testés positifs. Un taux d'infection minimum (MIR) de 2,52 pour 1000 moustiques a été estimé pour Ae. aegypti. Les sérotypes DENV-1, DENV-2 et DENV-3 ont été détectés même pendant les périodes inter-épidémiques. CONCLUSIONS: Cette étude rapporte les preuves de transmission verticale du virus de la dengue avec isolement viral et confirmation moléculaire dans les œufs d'Ae. Aegypti collectés dans quatre régions d'endémie du centre et du sud du Mexique. La transmission verticale pourrait jouer un rôle de mécanisme réservoir lors de la dormance des moustiques en période inter-épidémique, mais avec une participation mineure à la transmission en période d'épidémie.


Assuntos
Aedes/virologia , Vírus da Dengue/crescimento & desenvolvimento , Dengue/epidemiologia , Dengue/transmissão , Mosquitos Vetores/virologia , Animais , Cidades , Transmissão Vertical de Doenças Infecciosas , México/epidemiologia , Estações do Ano
16.
Appl Microbiol Biotechnol ; 103(4): 1865-1876, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30539256

RESUMO

The environmental strain Aeromonas salmonicida subsp. pectinolytica 34melT produces abundant melanin through the homogentisate pathway in several culture media, but unexpectedly not when grown in a medium containing glycerol. Using this observation as a starting point, this study investigated the underlying causes of the inhibition of melanin synthesis by glycerol, to shed light on factors that affect melanin production in this microorganism. The effect of different carbon sources on melanin formation was related to the degree of oxidation of their C atoms, as the more reduced substrates delayed melanization more than the more oxidized ones, although only glycerol completely abolished melanin production. Glyphosate, an inhibitor of aromatic amino acid synthesis, did not affect melanization, while bicyclopyrone, an inhibitor of 4-hydroxyphenylpyruvate dioxygenase (Hpd), the enzyme responsible for the synthesis of homogentisate, prevented melanin synthesis. These results showed that melanin production in 34melT depends on the degradation of aromatic amino acids from the growth medium and not on de novo aromatic amino acid synthesis. The presence of glycerol changed the secreted protein profile, but none of the proteins affected could be directly connected with melanin synthesis or transport. Transcription analysis of hpd, encoding the key enzyme for melanin synthesis, showed a clear inhibition caused by glycerol. The results obtained in this work indicate that a significant decrease in the transcription of hpd, together with a more reduced intracellular state, would lead to the abolishment of melanin synthesis observed. The effect of glycerol on melanization can thus be attributed to a combination of metabolic and regulatory effects.


Assuntos
Aeromonas salmonicida/metabolismo , Glicerol/metabolismo , Melaninas/antagonistas & inibidores , Aminoácidos Aromáticos/metabolismo , Biotransformação , Carbono/metabolismo , Meios de Cultura/química , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos
17.
Int J Syst Evol Microbiol ; 68(5): 1627-1632, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29595416

RESUMO

The genus Coprothermobacter (initially named Thermobacteroides) is currently placed within the phylum Firmicutes. Early 16S rRNA gene based phylogenetic studies pointed out the great differences between Coprothermobacter and other members of the Firmicutes, revealing that it constitutes a new deep branching lineage. Over the years, several studies based on 16S rRNA gene and whole genome sequences have indicated that Coprothermobacter is very distant phylogenetically to all other bacteria, supporting its placement in a distinct deeply rooted novel phylum. In view of this, we propose its allocation to the new family Coprothermobacteraceae within the novel order Coprothermobacterales, the new class Coprothermobacteria, and the new phylum Coprothermobacterota, and an emended description of the family Thermodesulfobiaceae.


Assuntos
Firmicutes/classificação , Filogenia , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
18.
J Chem Phys ; 148(21): 214901, 2018 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-29884038

RESUMO

In this work, we present results of coarse-grained simulations to study the encapsulation of prilocaine (PLC), both neutral and protonated, on copolymer bilayers through molecular dynamics simulations. Using a previously validated membrane model, we have simulated loaded bilayers at different drug concentrations and at low (protonated PLC) and high (neutral PLC) pH levels. We have characterized key structural parameters of the loaded bilayers in order to understand the effects of encapsulation of PLC on the bilayer structure and mechanical properties. Neutral PLC was encapsulated in the hydrophobic region leading to a thickness increase, while the protonated species partitioned between the water phase and the poly(ethylene oxide)-poly(butadiene) (PBD) interface, relaxing the PBD region and leading to a decrease in the thickness. The tangential pressures of the studied systems were calculated, and their components were decomposed in order to gain insights on their compensation. In all cases, it is observed that the loading of the membrane does not significantly decrease the stability of the bilayer, indicating that the system could be used for drug delivery.

19.
J Transl Med ; 15(1): 62, 2017 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-28320414

RESUMO

BACKGROUND: Inguinal orchiectomy is curative in 70-80% of clinical stage I testicular germ cell tumours (CS I TGCT). The identification of patients who are at low risk of relapse is critical to avoid unnecessary treatment. The aim of this study is to explore EGFR, hMLH-1/hMSH-2 and microsatellite instability (MSI) as potential prognostic factors of recurrence in CS I TGCT. METHODS: Fifty-six CS I TGCT patients who underwent inguinal orchiectomy were included in this study. We analysed the relationship between clinicopathological and molecular factors with survival. Analysis of hMLH1, hMSH2 and EGFR expression was carried out by immunohistochemistry. Methylation status of the hMLH1 promoter was determined by pyrosequencing analysis in selected cases. EGFR exons 19, 20, 21 were analysed by PCR labeled-fragments and MSI status was determined using standard Multiplex MSI assays. RESULTS: Classical pathological factors such as lymphovascular invasion, high percentage of embryonal carcinoma, rete testis invasion or tumour size ≥4 cm showed a significant relationship with a higher risk of relapse. Additionally, it was found that an epididymis invasion proved to be a significant independent poor prognostic factor of recurrence (p = 0.001). hMLH1 or hMSH2 expression showed no significant association with risk of relapse and no MSI was found. EGFR expression was observed in 30.4% of samples and its expression was associated with higher risk of relapse (HR 3.5; 95% CI 1.3-9.8; p = 0.016). None of the cases presented EGFR kinase domain mutations. CONCLUSIONS: Epididymis invasion and EGFR expression, but not hMLH-1/hMSH-2 or MSI, could be potentially useful as new prognostic factors of recurrence for CS I TGCT.


Assuntos
Biomarcadores Tumorais/metabolismo , Epididimo/patologia , Receptores ErbB/metabolismo , Neoplasias Embrionárias de Células Germinativas/metabolismo , Neoplasias Embrionárias de Células Germinativas/patologia , Neoplasias Testiculares/metabolismo , Neoplasias Testiculares/patologia , Adulto , Metilação de DNA/genética , Demografia , Intervalo Livre de Doença , Éxons/genética , Genoma Humano , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Masculino , Instabilidade de Microssatélites , Proteína 1 Homóloga a MutL/genética , Proteína 2 Homóloga a MutS/metabolismo , Invasividade Neoplásica , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Neoplasias Embrionárias de Células Germinativas/genética , Prognóstico , Regiões Promotoras Genéticas , Fatores de Risco , Neoplasias Testiculares/genética
20.
J Chem Phys ; 146(24): 244904, 2017 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-28668049

RESUMO

This paper presents a new model for polymersomes developed using a poly(ethylene oxide)-poly(butadiene) diblock copolymer bilayer. The model is based on a coarse-grained approach using the MARTINI force field. Since no MARTINI parameters exist for poly(butadiene), we have refined these parameters using quantum mechanical calculations and molecular dynamics simulations. The model has been validated using extensive molecular dynamics simulations in systems with several hundred polymer units and reaching up to 6 µs. These simulations show that the copolymer coarse grain model self-assemble into bilayers and that NPT and NPNγT ensemble runs reproduce key structural and mechanical experimental properties for different copolymer length chains with a similar hydrophilic weight fraction.

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