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1.
Nano Lett ; 22(18): 7621-7627, 2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36074722

RESUMO

Organic-inorganic layered perovskites are currently some of the most promising 2D van der Waals materials. Low crystal quality usually broadens the exciton line width, obscuring the fine structure of the exciton in conventional photoluminescence experiments. Here, we propose a mechanical approach to reducing the effect of spectral diffusion by means of hBN capping on layered perovskites, revealing the exciton fine structure. We used a stochastic model to link the reduction of the spectral line width with the population of charge fluctuation centers present in the organic spacer. van der Waals forces between both lattices cause the partial clamping of the perovskite organic spacer molecules, and hence the amplitude of the overall spectral diffusion effect is reduced. Our work provides a low-cost solution to the problem of accessing important fine-structure excitonic state information, along with an explanation of the important carrier dynamics present in the organic spacer that affect the quality of the optical emission.

2.
Med Res Rev ; 42(1): 56-82, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-33851452

RESUMO

Calcium channels (CCs), a group of ubiquitously expressed membrane proteins, are involved in many pathophysiological processes of protozoan parasites. Our understanding of CCs in cell signaling, organelle function, cellular homeostasis, and cell cycle control has led to improved insights into their structure and functions. In this article, we discuss CCs characteristics of five major protozoan parasites Plasmodium, Leishmania, Toxoplasma, Trypanosoma, and Cryptosporidium. We provide a comprehensive review of current antiparasitic drugs and the potential of using CCs as new therapeutic targets. Interestingly, previous studies have demonstrated that human CC modulators can kill or sensitize parasites to antiparasitic drugs. Still, none of the parasite CCs, pumps, or transporters has been validated as drug targets. Information for this review draws from extensive data mining of genome sequences, chemical library screenings, and drug design studies. Parasitic resistance to currently approved therapeutics is a serious and emerging threat to both disease control and management efforts. In this article, we suggest that the disruption of calcium homeostasis may be an effective approach to develop new anti-parasite drug candidates and reduce parasite resistance.


Assuntos
Criptosporidiose , Cryptosporidium , Parasitos , Animais , Cálcio/metabolismo , Cálcio/farmacologia , Homeostase , Humanos
3.
BMC Nephrol ; 23(1): 316, 2022 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-36127661

RESUMO

BACKGROUND: The co-administration of loop diuretics with thiazide diuretics is a therapeutic strategy in patients with hypertension and volume overload. The aim of this study was to assess the efficacy and safety of treatment with bumetanide plus chlorthalidone in patients with chronic kidney disease (CKD) stage 4-5 KDIGO. METHODS: A double-blind randomized study was conducted. Patients were randomized into two groups: bumetanide plus chlorthalidone group (intervention) and the bumetanide plus placebo group (control) to evaluate differences in TBW, ECW and ECW/TBW between baseline and 30 Days of follow-up. Volume overload was defined as 'bioelectrical impedance analysis as fluid volume above the 90th percentile of a presumed healthy reference population. The study's registration number was NCT03923933. RESULTS: Thirty-two patients with a mean age of 57.2 ± 9.34 years and a median estimated glomerular filtration rate (eGFR) of 16.7 ml/min/1.73 m2 (2.2-29) were included. There was decreased volume overload in the liters of total body water (TBW) on Day 7 (intervention: -2.5 vs. control: -0.59, p = 0.003) and Day 30 (intervention: -5.3 vs. control: -0.07, p = 0.016); and in liters of extracellular water (ECW) on Day 7 (intervention: -1.58 vs. control: -0.43, p < 0.001) and Day 30 (intervention: -3.05 vs. control: -0.15, p < 0.000). There was also a decrease in systolic blood pressure on Day 7 (intervention: -18 vs. control: -7.5, p = 0.073) and Day 30 (intervention: -26.1 vs. control: -10, p = 0.028) and in diastolic blood pressure on Day 7 (intervention: -8.5 vs. control: -2.25, p = 0.059) and Day 30 (intervention: -13.5 vs. control: -3.4, p = 0.018). CONCLUSION: In CKD stage 4-5 KDIGO without renal replacement therapy, bumetanide in combination with chlorthalidone is more effective in treating volume overload and hypertension than bumetanide with placebo.


Assuntos
Hipertensão , Insuficiência Renal Crônica , Desequilíbrio Hidroeletrolítico , Idoso , Bumetanida/uso terapêutico , Clortalidona/uso terapêutico , Humanos , Hipertensão/tratamento farmacológico , Pessoa de Meia-Idade , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/tratamento farmacológico , Terapia de Substituição Renal , Inibidores de Simportadores de Cloreto de Sódio/uso terapêutico , Inibidores de Simportadores de Cloreto de Sódio e Potássio/uso terapêutico , Água
4.
Rep Pract Oncol Radiother ; 27(3): 509-518, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36186704

RESUMO

Background: The objective was to to determine the radiosensitizing properties of eribulin and the potential mechanisms of radiosensitization in cervical (HeLa) and pharyngeal (FaDu) cancer cell lines. Materials and methods: Cytotoxicity was evaluated by the crystal violet method. The 10% and 50% inhibitory concentration (IC10, IC50) for 24-hour drug exposure were determined. The surviving fraction at 2 Gy (SF2) and the sensitizer enhancement ratio (SER) were calculated from radiation cell survival curves in the presence or absence of eribulin. Combination index (CI) was calculated to determine if there is a true synergistic interaction between eribulin and irradiation. Cell cycle changes were assessed by propidium iodide staining and flow cytometry. Apoptotic cells were detected by annexin V and TUNEL-assay. Results: Mean IC50s and IC10s were 1.58 nM and 0.7 nM and 0.7 nM and 0.27 nM for HeLa and FaDu cells, respectively. Radiosensitization was observed in both lines with a SER up to 2.71 and 2.32 for HeLa and FaDu cells, respectively. A true synergistic effect was showed with a CI of 0.82 and 0.76 for HeLa and FaDu cells, respectively. Eribulin induced significant G2/M cell arrest and marked apoptosis. Irradiation combined with 3 nM eribulin increased the apoptotic response to radiation in Hela cells. Conclusion: Eribulin shows a true in vitro radiosensitizing effect in HeLa and FaDu cells by inducing significant G2/M phase arrest. In HeLa, the enhancement radiation-induced apoptosis could be an additional mechanism of radiosensitization. Further studies are needed to evaluate the clinical benefits of concurrent eribulin and radiotherapy as a novel therapeutic strategy for cancer.

5.
Hum Mol Genet ; 28(19): 3327-3338, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31504550

RESUMO

Although hundreds of genome-wide association studies-implicated loci have been reported for adult obesity-related traits, less is known about the genetics specific for early-onset obesity and with only a few studies conducted in non-European populations to date. Searching for additional genetic variants associated with childhood obesity, we performed a trans-ancestral meta-analysis of 30 studies consisting of up to 13 005 cases (≥95th percentile of body mass index (BMI) achieved 2-18 years old) and 15 599 controls (consistently <50th percentile of BMI) of European, African, North/South American and East Asian ancestry. Suggestive loci were taken forward for replication in a sample of 1888 cases and 4689 controls from seven cohorts of European and North/South American ancestry. In addition to observing 18 previously implicated BMI or obesity loci, for both early and late onset, we uncovered one completely novel locus in this trans-ancestral analysis (nearest gene, METTL15). The variant was nominally associated with only the European subgroup analysis but had a consistent direction of effect in other ethnicities. We then utilized trans-ancestral Bayesian analysis to narrow down the location of the probable causal variant at each genome-wide significant signal. Of all the fine-mapped loci, we were able to narrow down the causative variant at four known loci to fewer than 10 single nucleotide polymorphisms (SNPs) (FAIM2, GNPDA2, MC4R and SEC16B loci). In conclusion, an ethnically diverse setting has enabled us to both identify an additional pediatric obesity locus and further fine-map existing loci.


Assuntos
Mapeamento Cromossômico/métodos , Estudo de Associação Genômica Ampla/métodos , Obesidade Infantil/genética , Polimorfismo de Nucleotídeo Único , Tumor de Wilms/genética , Teorema de Bayes , Estudos de Casos e Controles , Criança , Feminino , Loci Gênicos , Predisposição Genética para Doença , Humanos , Masculino
6.
Mol Biol Rep ; 48(2): 1579-1587, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33502700

RESUMO

Stomatal closure is a common adaptation response of plants to the onset of drought condition and its regulation is controlled by transcription factors. MYB60, a transcription factor involved in the regulation of light-induced stomatal opening, has been characterized in arabidopsis and grapevine. In this work, we studied the role of MYB60 homolog SIMYB60 in tomato plants. We identified, isolated, and sequenced the SIMYB60 coding sequence, and found domains and motifs characteristic of other MYB60 proteins. We determined that SlMYB60 is mainly expressed in leaves, and its expression is repressed by abscisic acid. Next, we isolated a putative promoter region containing regulatory elements responsible for guard cell expression and other putative regulatory elements related to ABA repression and vascular tissue expression. Protein localization assays demonstrated that SlMYB60 localizes to the nucleus. Finally, SlMYB60 is able to complement the mutant phenotype of atmyb60-1 in Arabidopsis. Together, these results indicate that SlMYB60 is the homologous gene in tomato and potentially offer a molecular target to improve crops.


Assuntos
Adaptação Fisiológica/genética , Proteínas de Arabidopsis/genética , Secas , Solanum lycopersicum/genética , Fatores de Transcrição/genética , Ácido Abscísico/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Solanum lycopersicum/crescimento & desenvolvimento , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/crescimento & desenvolvimento , Sequências Reguladoras de Ácido Nucleico/genética
7.
Rep Pract Oncol Radiother ; 26(2): 237-241, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34211774

RESUMO

BACKGROUND: The sanitary emergency created by the COVID-19 pandemic forced us to take exceptional measures that affect decision-making and administration of treatments with radiotherapy. The aim of the study was to analyze the impact of the COVID-19 pandemic on patients and professionals in a radiation oncology department. MATERIALS AND METHODS: We implement a plan with the objectives of maintaining radiotherapy treatment in those patients who need it and, at the same time, reducing the risk of spreading the virus to staff and patients. This plan included measures aimed at limiting the patient's stay in hospital, selecting those patients in whom radiotherapy cannot be delayed and protecting against infection through the use of physical protective measures. RESULTS: Between March 16 and May 31, 2020, 360 patients received radiotherapy in our department. In 14 patients (4.7%) the start of treatment was delayed by an average of 28 days. Four patients had a positive COVID-19 polymerase chain reaction (PCR ) (6.6% and 1.1% of tested and all patients, respectively). Among the professionals, two PCR s were positive (16.6% and 4% of tested and all individuals, respectively). In the serology analysis 4 out of 50 department members were IgG positive (8%). CONCLUSIONS: Despite the fact that our department is located in a region with a high incidence of COVID-19 infection, the impact of the pandemic on our patients and staff has been moderate. The implementation of measures against infection and an adequate selection of patients for treatment allows radiation oncology departments to maintain clinical activity.

8.
Pediatr Surg Int ; 36(2): 241-246, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31712873

RESUMO

OBJECTIVE: To determine the effect of tobacco consumption on paternity rates in men with a history of cryptorchidism. To compare the paternity rates between formerly unilateral, bilateral cryptorchid smokers, and nonsmokers. METHODS: A retrospective cohort study of 153 men who had undergone orchiopexy between 1961 and 1985 at the Miguel Servet University Hospital (116 unilateral and 37 bilateral) and a control group of 100 men were evaluated by review of medical records and a questionnaire. RESULTS: A total of 197 men filled the questionnaire (76.7%). There was no difference in paternity rates between smokers compared to nonsmokers (P = 0.21). In the unilateral cryptorchid men (ULC) group, there is no difference in paternity rates when compared with the controls (P = 0.079) or when comparing ULC smokers to ULC nonsmokers (P = 0.35). In the bilateral cryptorchid men (BLC) group, there is no difference in paternity rates when compared to controls (P = 0.075) or when comparing BLC smokers to BLC nonsmokers (P = 0.36). When comparing according to consumption, there is no difference between mild, moderate or heavy smoker cases and controls. CONCLUSION: There is no difference in paternity rates between men with a history of cryptorchidism that consume tobacco compared to nonsmokers or controls. More studies are needed to determine the impact of tobacco consumption in formerly cryptorchid men.


Assuntos
Criptorquidismo/epidemiologia , Fertilidade/fisiologia , Paternidade , Uso de Tabaco/epidemiologia , Adulto , Criptorquidismo/etiologia , Criptorquidismo/cirurgia , Humanos , Incidência , Masculino , Orquidopexia , Estudos Retrospectivos , Espanha/epidemiologia , Inquéritos e Questionários
9.
Dev Biol ; 435(1): 56-72, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29355521

RESUMO

GSK3 plays a central role in orchestrating key biological signaling pathways, including cell migration. Here, we identify GlkA as a GSK3 family kinase with functions that overlap with and are distinct from those of GskA. We show that GlkA, as previously shown for GskA, regulates the cell's cytoskeleton through MyoII assembly and control of Ras and Rap1 function, leading to aberrant cell migration. However, there are both qualitative and quantitative differences in the regulation of Ras and Rap1 and their downstream effectors, including PKB, PKBR1, and PI3K, with glkA- cells exhibiting a more severe chemotaxis phenotype than gskA- cells. Unexpectedly, the severe glkA- phenotypes, but not those of gskA-, are only exhibited when cells are grown attached to a substratum but not in suspension, suggesting that GlkA functions as a key kinase of cell attachment signaling. Using proteomic iTRAQ analysis we show that there are quantitative differences in the pattern of protein expression depending on the growth conditions in wild-type cells. We find that GlkA expression affects the cell's proteome during vegetative growth and development, with many of these changes depending on whether the cells are grown attached to a substratum or in suspension. These changes include key cytoskeletal and signaling proteins known to be essential for proper chemotaxis and signal relay during the aggregation stage of Dictyostelium development.


Assuntos
Quimiotaxia/fisiologia , Dictyostelium/enzimologia , Regulação Enzimológica da Expressão Gênica/fisiologia , Quinase 3 da Glicogênio Sintase/biossíntese , Proteínas de Protozoários/biossíntese , Transdução de Sinais/fisiologia , Dictyostelium/genética , Quinase 3 da Glicogênio Sintase/genética , Proteínas de Protozoários/genética
10.
Int J Obes (Lond) ; 43(1): 23-32, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29769702

RESUMO

BACKGROUND/OBJECTIVES: Mexico has one of the highest prevalence of childhood obesity in the world. Genome-wide association studies (GWAS) for obesity have identified multiple single-nucleotide polymorphisms (SNPs) in populations of European, East Asian, and African descent. The contribution of these loci to obesity in Mexican children is unclear. We assessed the transferability of 98 obesity loci in Mexican children and fine-mapped the association signals. SUBJECTS/METHODS: The study included 405 and 390 Mexican children with normal weight and obesity. Participants were genotyped with a genome-wide dense SNP array designed for Latino populations, allowing for the analysis of GWAS index SNPs as well as fine-mapping SNPs, totaling 750 SNPs covering 98 loci. Two genetic risk scores (GRS) were constructed: a "discovery GRS" and a "best-associated GRS", representing the number of effect alleles at the GWAS index SNPs and at the best-associated SNPs after fine-mapping for each subject. RESULTS: Seventeen obesity loci were significantly associated with obesity, and five had fine-mapping SNPs significantly better associated with obesity than their corresponding GWAS index SNPs in Mexican children. Six obesity-associated SNPs significantly departed from additive to dominant (N = 5) or recessive (N = 1) models, and a significant interaction was found between rs274609 (TNNI3K) and rs1010553 (ITIH4) on childhood obesity risk. The best-associated GRS was significantly more associated with childhood obesity (OR = 1.21 per additional risk allele [95%CI:1.17-1.25], P = 4.8 × 10-25) than the discovery GRS (OR = 1.05 per additional risk allele [95%CI:1.02-1.08], P = 8.0 × 10-4), and was also associated with waist-to-hip ratio, fasting glucose, fasting insulin and triglyceride levels, the association being mediated by obesity. An overall depletion of obesity risk alleles was observed in Mexican children with normal weight when compared to GWAS discovery populations. CONCLUSIONS: Our study indicates a partial transferability of GWAS obesity loci in Mexican children, and supports the pertinence of post-GWAS fine-mapping experiments in the admixed Mexican population.


Assuntos
Predisposição Genética para Doença/epidemiologia , Estudo de Associação Genômica Ampla , Obesidade/genética , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Criança , Jejum/sangue , Feminino , Frequência do Gene , Loci Gênicos , Humanos , Estilo de Vida , Masculino , México/epidemiologia , Obesidade/sangue , Obesidade/epidemiologia , Fatores Socioeconômicos
11.
Int J Obes (Lond) ; 43(1): 13-22, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29777226

RESUMO

BACKGROUND/OBJECTIVES: The prevalence of abdominal obesity in Mexican children has risen dramatically in the past decade. Genome-wide association studies (GWAS) for waist-to-hip ratio (WHR) performed predominantly in European descent adult  populations have identified multiple single-nucleotide polymorphisms (SNPs) with larger effects in women. The contribution of these SNPs to WHR in non-European children is unknown. SUBJECTS/METHODS: Mexican children and adolescents (N = 1421, 5-17 years) were recruited in Mexico City. Twelve GWAS SNPs were genotyped using TaqMan Open Array and analyzed individually and as a gene score (GS). RESULTS: Mexican boys and girls displayed 2.81 ± 0.29 and 3.10 ± 0.31 WHR standard deviations higher than children and adolescents from the United States. WHR was positively associated with TG (ß = 0.733 ± 0.190, P = 1.1 × 10-4) and LDL-C (ß = 0.491 ± 0.203, P = 1.6 × 10-2), and negatively associated with HDL-C (ß = -0.652 ± 0.195, P = 8.0 × 10-4), independently of body mass index. The effect allele frequency (EAF) of 8 of 12 (67%) SNPs differed significantly (P < 4.17 × 10-3) in Mexican children and European adults, with no evidence of effect allele enrichment in both populations (4 depleted and 4 enriched; binomial test, P = 1). Ten out of 12 SNPs (83.3%) had effects that were directionally consistent with those reported in GWAS (P = 0.04). HOXC13 rs1443512 displayed the best fit when modeled recessively, and was significantly associated with WHR under a recessive mode of inheritance (ß = 0.140 ± 0.06, P = 2.3 × 10-2). Significant interactions with sex were also observed for HOXC13 rs1443512 and the GS on WHR (P = 2.2 × 10-2 and 1.2 × 10-2, respectively). HOXC13 rs1443512 (ß = 0.022 ± 0.012, P = 4.7 × 10-2) and the GS (ß = 0.007 ± 0.003, P = 7.0 × 10-3) were significantly associated with WHR in girls only. CONCLUSIONS: This study demonstrates that Mexican children are at high risk for abdominal obesity and detrimental lipid profiles. Our data support a partial transferability of sex-specific European GWAS WHR association signals in children and adolescents from the admixed Mexican population.


Assuntos
Estudo de Associação Genômica Ampla , Obesidade Abdominal/genética , Polimorfismo de Nucleotídeo Único/genética , Relação Cintura-Quadril , Adolescente , Adulto , Índice de Massa Corporal , Criança , Estudos Transversais , Europa (Continente) , Feminino , Frequência do Gene , Loci Gênicos , Genótipo , Humanos , Estilo de Vida , Masculino , México/epidemiologia , Obesidade Abdominal/epidemiologia , Prevalência
12.
Ecotoxicol Environ Saf ; 182: 109382, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31255867

RESUMO

Polycyclic aromatic hydrocarbons (PAH) have become a threat for the conservation of wetlands worldwide. The halophyte Spartina densiflora has shown to be potentially useful for soil phenanthrene phytoremediation, but no studies on bacteria-assisted hydrocarbon phytoremediation have been carried out with this halophyte. In this work, three phenanthrene-degrading endophytic bacteria were isolated from S. densiflora tissues and used for plant inoculation. Bacterial bioaugmentation treatments slightly improved S. densiflora growth, photosynthetic and fluorescence parameters. But endophyte-inoculated S. densiflora showed lower soil phenanthrene dissipation rates than non-inoculated S. densiflora (30% below) or even bulk soil (23% less). Our work demonstrates that endophytic inoculation on S. densiflora under greenhouse conditions with the selected PAH-degrading strains did not significantly increase inherent phenanthrene soil dissipation capacity of the halophyte. It would therefore be advisable to provide effective follow-up of bacterial colonization, survival and metabolic activity during phenanthrene soil phytoremediation.


Assuntos
Bactérias/metabolismo , Fenantrenos/análise , Poaceae/metabolismo , Plantas Tolerantes a Sal/metabolismo , Poluentes do Solo/análise , Solo/química , Biodegradação Ambiental , Endófitos/metabolismo , Fotossíntese , Poaceae/microbiologia , Plantas Tolerantes a Sal/microbiologia , Microbiologia do Solo , Áreas Alagadas
13.
Int J Phytoremediation ; 21(6): 550-555, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30648414

RESUMO

The research on the plant population metal intra-specific tolerance variability is of paramount importance for the design of phytoremediation restoration. The aim of this study was to asses if any variability exists in the copper stress response during seed germination and seedling development in Juncus acutus depending on provenance habitat. Our results showed that J. acutus were able to germinate until Cu concentration of 23 mM Cu, but at 15 and 23 mM Cu, the final percentage of germination were 100 and 68% for seeds derived from polluted area and were 86 and 40% for those collected in non-polluted one, respectively. Moreover, the germination kinetic was more impaired by Cu concentration in those no historically exposed to metal excess. Provenance effect was also reflected in seedlings survival and development; thus at 9 mM Cu higher survival percentage, total height and dry mass were recorded in seedlings derived from no polluted area compared with their historically exposed counterparts. Therefore, we can conclude that the variability of Cu tolerance in J. acutus should be considered for the design of restoration projects, since it allows use of provenances with greater potential as a source of propagules highly adapted to metal excess.


Assuntos
Germinação , Sementes , Biodegradação Ambiental , Metais , Plântula
14.
Bioorg Med Chem ; 26(4): 815-823, 2018 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-29398445

RESUMO

Chemically modified versions of bioactive substances, are particularly useful in overcoming barriers associated with drug formulation, drug delivery and poor pharmacokinetic properties. In this study, a series of fourteen (E)-methyl 2-(7-chloroquinolin-4-ylthio)-3-(4-hydroxyphenyl) acrylate (2-15) were prepared by using a one step synthesis from 1 previously described by us as potential antimalarial and antitumor agent. Molecules were evaluated as inhibitors of ß-hematin formation, where most of them showed a significant inhibition value (% > 70). The best inhibitors were tested in vivo as potential antimalarials in mice infected with P. berghei ANKA, chloroquine susceptible strain. Three of them (5, 6, and 15) displayed antimalarial activity comparable to that of chloroquine. Also, molecules were evaluated for their cytotoxic activity against two human cancer cell lines (Jurkat E6.1 and HL60) and primary culture of human lymphocytes. Most of the synthesized compounds, except for analogs 2-6, 8, and 10-12, displayed cytotoxicity against cancer cell lines without affecting normal cells. The potency of the compounds was 15 ≫ 1, and 14 > 7, 9, and 13. Flow cytometry analysis demonstrated an increase in apoptotic cell death after 24 h. The compounds may affect tumor cell autophagy and consequently increase cell apoptosis.


Assuntos
Acrilatos/química , Antimaláricos/química , Antineoplásicos/química , Cloroquina/química , Acrilatos/farmacologia , Acrilatos/uso terapêutico , Animais , Antimaláricos/farmacologia , Antimaláricos/uso terapêutico , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Células Cultivadas , Cloroquina/farmacologia , Células HL-60 , Hemina/antagonistas & inibidores , Hemina/metabolismo , Humanos , Células Jurkat , Malária/tratamento farmacológico , Malária/patologia , Malária/veterinária , Camundongos , Plasmodium berghei/efeitos dos fármacos , Estereoisomerismo , Relação Estrutura-Atividade
15.
Phys Chem Chem Phys ; 20(48): 30189-30199, 2018 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-30489581

RESUMO

The employment of bulky aliphatic cations in the manufacture of moisture-stable materials has triggered the development and application of 2D/3D perovskites as sensitizers in moisture-stable solar cells. Although it is true that the moisture stability increases, it is also true that the photovoltaic performance of 2D/3D PVK materials is severely limited owing to quantum and dielectric confinement effects. Accordingly, it is necessary the synthesis and deep optical characterization of materials with an adequate management of dielectric contrast between the layers. Here, we demonstrate the successful tuning of dielectric confinement by the inclusion of a conjugated molecule, as a bulky cation, in the fabrication of the 2D/3D PVK material (C6H5NH3)2(CH3NH3)n-1PbnI3n+1, where n = 3 or 5. The absence of excitonic states related to n ≥ 1 at room temperature, as well as the very low concentration of excitons after 1 ps of excitation of samples in which n ≥ 3, provide strong evidence of an excellent ability to dissociate excitons into free charge carriers. As consequence films with low n, presenting higher stability than standard 3D perovskites, improved significantly their performance, showing one of the highest short circuit current density (Jsc ≈ 13.8) obtained to date for perovskite materials within the 2D limit (n < 10).

16.
Ecotoxicol Environ Saf ; 163: 478-485, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30075451

RESUMO

The potential importance of Juncus acutus for remediation of Zn-contaminated lands has been recognized, because of its Zn tolerance and capacity to accumulate Zn. Since it is also a halophyte, the extent to which salinity influences its Zn tolerance requires investigation. A factorial greenhouse experiment was designed to assess the effect of NaCl supply (0 and 85 mM NaCl) on the growth, photosynthetic physiology and tissue ions concentrations of plants exposed to 0, 30 and 100 mM Zn. Our results indicated that NaCl supplementation alleviated the effects of Zn toxicity on growth, as Zn at 100 mM reduced relative growth rate (RGR) by 60% in the absence of NaCl but by only 34% in plants treated also with NaCl. This effect was linked to a reduction in Zn tissue concentrations, as well as to overall protective effects on various stages in the photosynthetic pathway. Thus, at 85 mM NaCl plants were able to maintain higher net photosynthesis (AN) than in the absence of added NaCl, although there were no differences in stomatal conductance (gs). This contributed to preserving the trade-off between CO2 acquisition and water loss, as indicated by higher intrinsic water use efficiency (iWUE). Hence, AN differences were ascribed to limitation in the RuBisCO carboxylation, manifested as higher intercellular CO2 concentration (Ci), together with dysfunction of PSII photochemistry (in term of light harvest and energy excess dissipation), as indicated by higher chronic photoinhibition percentages and variations in the photosynthetic pigment profiles in presence of Zn under non-saline conditions.


Assuntos
Magnoliopsida/efeitos dos fármacos , Salinidade , Plantas Tolerantes a Sal/efeitos dos fármacos , Cloreto de Sódio/toxicidade , Zinco/toxicidade , Clorofila/metabolismo , Magnoliopsida/metabolismo , Fotossíntese/efeitos dos fármacos , Plantas Tolerantes a Sal/metabolismo , Áreas Alagadas
17.
BMC Cancer ; 17(1): 79, 2017 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-28122528

RESUMO

BACKGROUND: Cervical Cancer (CC) has become a public health concern of alarming proportions in many developing countries such as Mexico, particularly in low income sectors and marginalized regions. As such, an early detection is a key medical factor in improving not only their population's quality of life but also its life expectancy. Interestingly, there has been an increase in the number of reports describing successful attempts at detecting cancer cells in human tissues or fluids using trained (sniffer) dogs. The great odor detection threshold exhibited by dogs is not unheard of. However, this represented a potential opportunity to develop an affordable, accessible, and non-invasive method for detection of CC. METHODS: Using clicker training, a male beagle was trained to recognize CC odor. During training, fresh CC biopsies were used as a reference point. Other samples used included cervical smears on glass slides and medical surgical bandages used as intimate sanitary pads by CC patients. A double-blind procedure was exercised when testing the beagle's ability to discriminate CC from control samples. RESULTS: The beagle was proven able to detect CC-specific volatile organic compounds (VOC) contained in both fresh cervical smear samples and adsorbent material samples. Beagle's success rate at detecting and discriminating CC and non-CC odors, as indicated by specificity and sensitivity values recorded during the experiment, stood at an overall high (>90%). CC-related VOC in adsorbent materials were detectable after only eight hours of use by CC patients. CONCLUSION: Present data suggests different applications for VOC from the uterine cervix to be used in the detection and diagnosis of CC. Furthermore, data supports the use of trained dogs as a viable, affordable, non-invasive and, therefore, highly relevant alternative method for detection of CC lesions. Additional benefits of this method include its quick turnaround time and ease of use while remaining highly accurate and robust.


Assuntos
Neoplasias do Colo do Útero/diagnóstico , Animais , Biomarcadores Tumorais/metabolismo , Cães , Método Duplo-Cego , Detecção Precoce de Câncer , Feminino , Humanos , Masculino , Odorantes , Sensibilidade e Especificidade , Neoplasias do Colo do Útero/metabolismo
18.
Qual Life Res ; 26(12): 3227-3238, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28780713

RESUMO

PURPOSE: We analyzed gender differences in health-related quality of life (HRQoL) and associated factors between informal male and female caregivers in Spain. It is important because of growing rates of dependent people and dwindling public resources. METHODS: We conducted a cross-sectional study of 610 informal caregivers (265 male and 345 female) using an ad hoc structured questionnaire. We performed a descriptive analysis and used multivariate logistic regression to analyze the risk of poor HRQoL, measured with the EQ-5D-5L, according to caregiver sex, sociodemographic characteristics of caregivers and dependents, caregiving circumstances, and support received. RESULTS: Male caregivers were older than women were, and cared more often for their partners. More women used family caregiving allowance (FCA), respite care services, and counseling services, while more men used paid help, home help, and other forms of instrumental help. Women had worse HRQoL than men, particularly in the pain/discomfort dimension. In addition to older age and poor previous health, caring for a partner (OR = 2.379), for a person with major dependence (OR = 1.917), low social class (OR = 1.634), and low social support (OR = 2.311) were factors associated with poor HRQoL. Receiving FCA was associated with better HRQoL (OR = 0.319). Controlling for all these variables, women had 131% more odds than men to have poor HRQoL. CONCLUSIONS: Male and female caregivers in Spain differ in received support and how their HRQoL is affected. These differences are important to design interventions to promote more equitable sharing of care responsibilities and better caregiver health.


Assuntos
Cuidadores/psicologia , Perfil de Impacto da Doença , Estudos Transversais , Feminino , Identidade de Gênero , Humanos , Masculino , Pessoa de Meia-Idade , Apoio Social , Espanha , Inquéritos e Questionários
19.
J Phys Chem A ; 120(25): 4314-24, 2016 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-27281172

RESUMO

Design parameters derived from structure-property relationships play a very important role in the development of efficient molecular-based functional materials with optical properties. Here, we report on the linear and nonlinear optical properties of a fluorene-derived dipolar system (DS) and its octupolar analogue (OS), in which donor and acceptor groups are connected by a phenylacetylene linkage, as a strategy to increase the number of delocalized electrons in the π-conjugated system. The optical nonlinear response was analyzed in detail by experimental and theoretical methods, showing that, in the octupolar system OS, the dipolar effects induced a strong two-photon absorption process whose magnitude is as large as 2210 GM at infrared wavelengths. Solvatochromism studies were implemented to obtain further insight on the charge transfer process. We found that the triple bond plays a fundamental role in the linear and nonlinear optical responses. The strong solvatochromism behavior in DS and OS was analyzed by using four empirical solvent scales, namely Lippert-Mataga, Kamlet-Taft, Catalán, and the recently proposed scale of Laurence et al., finding consistent results of strong solvent polarizability and viscosity dependence. Finally, the role of the acceptor groups was further studied by synthesizing the analogous compound 2DS, having no acceptor group.

20.
Diabetologia ; 58(2): 290-4, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25394825

RESUMO

AIMS/HYPOTHESIS: Childhood obesity is a major public health problem in Mexico, affecting one in every three children. Genome-wide association studies identified genetic variants associated with childhood obesity, but a large missing heritability remains to be elucidated. We have recently shown a strong association between a highly polymorphic copy number variant encompassing the salivary amylase gene (AMY1 also known as AMY1A) and obesity in European and Asian adults. In the present study, we aimed to evaluate the association between AMY1 copy number and obesity in Mexican children. METHODS: We evaluated the number of AMY1 copies in 597 Mexican children (293 obese children and 304 normal weight controls) through highly sensitive digital PCR. The effect of AMY1 copy number on obesity status was assessed using a logistic regression model adjusted for age and sex. RESULTS: We identified a marked effect of AMY1 copy number on reduced risk of obesity (OR per estimated copy 0.84, with the number of copies ranging from one to 16 in this population; p = 4.25 × 10(-6)). The global association between AMY1 copy number and reduced risk of obesity seemed to be mostly driven by the contribution of the highest AMY1 copy number. Strikingly, all children with >10 AMY1 copies were normal weight controls. CONCLUSIONS/INTERPRETATION: Salivary amylase initiates the digestion of dietary starch, which is highly consumed in Mexico. Our current study suggests putative benefits of high number of AMY1 copies (and related production of salivary amylase) on energy metabolism in Mexican children.


Assuntos
Metabolismo dos Carboidratos/genética , Obesidade/genética , alfa-Amilases Salivares/metabolismo , Índice de Massa Corporal , Criança , Feminino , Predisposição Genética para Doença/genética , Variação Genética , Estudo de Associação Genômica Ampla , Humanos , Modelos Logísticos , Masculino , México/epidemiologia , Obesidade/epidemiologia , Saúde Pública , alfa-Amilases Salivares/genética
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