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1.
Physiology (Bethesda) ; 39(1): 0, 2024 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-37905983

RESUMEN

One of the biggest environmental alterations we have made to our species is the change in the exposure to light. During the day, we typically sit behind glass windows illuminated by artificial light that is >400 times dimmer and has a very different spectrum than natural daylight. On the opposite end are the nights that are now lit up by several orders of magnitude. This review aims to provide food for thought as to why this matters for humans and other animals. Evidence from behavioral neuroscience, physiology, chronobiology, and molecular biology is increasingly converging on the conclusions that the biological nonvisual functions of light and photosensory molecules are highly complex. The initial work of von Frisch on extraocular photoreceptors in fish, the identification of rhodopsins as the molecular light receptors in animal eyes and eye-like structures and cryptochromes as light sensors in nonmammalian chronobiology, still allowed for the impression that light reception would be a relatively restricted, localized sense in most animals. However, light-sensitive processes and/or sensory proteins have now been localized to many different cell types and tissues. It might be necessary to consider nonlight-responding cells as the exception, rather than the rule.


Asunto(s)
Criptocromos , Células Fotorreceptoras de Invertebrados , Humanos , Animales , Células Fotorreceptoras de Invertebrados/fisiología
2.
Arch Microbiol ; 206(3): 97, 2024 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-38349544

RESUMEN

Cordyceps militaris is a well-known medicinal mushroom in Asian countries. This edible fungus has been widely exploited for traditional medicine and functional food production. C. militaris is a heterothallic fungus that requires both the mating-type loci, MAT1-1 and MAT1-2, for fruiting body formation. However, recent studies also indicated two groups of C. militaris, including monokaryotic strains carrying only MAT1-1 in their genomes and heterokaryotic strains harboring both MAT1-1 and MAT1-2. These strain groups are able to produce fruiting bodies under suitable cultivating conditions. In previous work, we showed that monokaryotic strains are more stable than heterokaryotic strains in fruiting body formation through successive culturing generations. In this study, we report a high cordycepin-producing monokaryotic C. militaris strain (HL8) collected in Vietnam. This strain could form normal fruiting bodies with high biological efficiency and contain a cordycepin content of 14.43 mg/g lyophilized fruiting body biomass. The ethanol extraction of the HL8 fruiting bodies resulted in a crude extract with a cordycepin content of 69.15 mg/g. Assays of cytotoxic activity on six human cancer cell lines showed that the extract inhibited the growth of all these cell lines with the IC50 values of 6.41-11.51 µg/mL. Notably, the extract significantly reduced cell proliferation and promoted apoptosis of breast cancer cells. Furthermore, the extract also exhibited strong antifungal activity against Malassezia skin yeasts and the citrus postharvest pathogen Penicillium digitatum. Our work provides a promising monokaryotic C. militaris strain as a bioresource for medicine, cosmetics, and fruit preservation.


Asunto(s)
Antineoplásicos , Cordyceps , Neoplasias , Penicillium , Humanos , Penicillium/genética , Cuerpos Fructíferos de los Hongos
3.
J Chem Inf Model ; 64(5): 1644-1656, 2024 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-38423522

RESUMEN

A deeper understanding of the inactive conformations of the coronavirus main protease (MPro) could inform the design of allosteric drugs. Based on extensive molecular dynamics simulations, we built a Markov State Model to investigate structural changes that can inactivate the SARS-CoV-2 MPro. In a subset of structures, one subunit of the homodimer assumes an inactive conformation that resembles an inactive crystal structure. However, contradicting the widely held half-of-sites activity hypothesis, the most populated enzyme structures have two active subunits. We then used transition path theory (TPT) and the Jensen-Shannon Divergence (JSD) to pinpoint residues involved in the inactivation process. A π stack between Phe140 and His163 is a key feature that can distinguish active and inactive conformations of MPro. Each subunit has unique inactive conformations stabilized by π stacking interactions involving residues Phe140, Tyr118, His163, and His172, a hydrogen bonding network centered around His163 and His172, and a modified network of interactions in the dimer interface. The importance of these residues in maintaining an active structure explains the sensitivity of enzymatic activity to site-directed mutagenesis.


Asunto(s)
Simulación de Dinámica Molecular , SARS-CoV-2 , Péptido Hidrolasas , Inhibidores de Proteasas/química , Simulación del Acoplamiento Molecular
4.
Int J Behav Med ; 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38942977

RESUMEN

BACKGROUND: Adolescents account for 15% of new HIV cases in Kenya. HIV pre-exposure prophylaxis (PrEP) and post-exposure prophylaxis (PEP) are highly effective prevention tools, but uptake is low among adolescents, particularly in resource-limited settings. We assessed awareness and acceptability of PrEP and PEP among Kenyan adolescents. METHOD: Focus group discussions were conducted with 120 adolescent boys and girls ages 15 to 19 in Kisumu. Data were analyzed using the Framework Approach. RESULTS: Adolescent participants often had not heard of or could not differentiate between PrEP and PEP. They also confused these HIV prevention tools with emergency contraceptives. Taking a daily pill to prevent HIV was perceived as analogous to taking a pill to treat HIV. Boys were aware of and willing to consider using PrEP and PEP due to their dislike for using condoms. Adolescents identified insufficient information, cost, and uncomfortableness speaking with healthcare workers about their HIV prevention needs due to sexuality stigma as barriers to using PrEP and PEP. CONCLUSION: Low awareness and poor understanding of PrEP and PEP among adolescents reveal the need for increased education and sensitization about these HIV prevention options. Expanding access to sexual and reproductive health services that are tailored to the needs of adolescents and staffed with non-judgmental providers could help reduce sexuality stigma as a barrier to accessing care. New HIV prevention approaches such as long-acting injectables or implants, on-demand regimens, and multipurpose prevention technologies may encourage increased uptake of PrEP and PEP by adolescents.

5.
Int J Mol Sci ; 25(6)2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38542268

RESUMEN

Recently, artificial exosomes have been developed to overcome the challenges of natural exosomes, such as production scalability and stability. In the production of artificial exosomes, the incorporation of membrane proteins into lipid nanostructures is emerging as a notable approach for enhancing biocompatibility and treatment efficacy. This study focuses on incorporating HEK293T cell-derived membrane proteins into liposomes to create membrane-protein-bound liposomes (MPLCs), with the goal of improving their effectiveness as anticancer therapeutics. MPLCs were generated by combining two key elements: lipid components that are identical to those in conventional liposomes (CLs) and membrane protein components uniquely derived from HEK293T cells. An extensive comparison of CLs and MPLCs was conducted across multiple in vitro and in vivo cancer models, employing advanced techniques such as cryo-TEM (tramsmission electron microscopy) imaging and FT-IR (fourier transform infrared spectroscopy). MPLCs displayed superior membrane fusion capabilities in cancer cell lines, with significantly higher cellular uptake. Additionally, MPLCs maintained their morphology and size better than CLs when exposed to FBS (fetal bovine serum), suggesting enhanced serum stability. In a xenograft mouse model using HeLa and ASPC cancer cells, intravenous administration of MPLCs MPLCs accumulated more in tumor tissues, highlighting their potential for targeted cancer therapy. Overall, these results indicate that MPLCs have superior tumor-targeting properties, possibly attributable to their membrane protein composition, offering promising prospects for enhancing drug delivery efficiency in cancer treatments. This research could offer new clinical application opportunities, as it uses MPLCs with membrane proteins from HEK293T cells, which are known for their efficient production and compatibility with GMP (good manufacturing practice) standards.


Asunto(s)
Liposomas , Nanoestructuras , Humanos , Ratones , Animales , Liposomas/química , Células HEK293 , Espectroscopía Infrarroja por Transformada de Fourier , Proteínas de la Membrana , Lípidos/química
6.
Pharmacogenet Genomics ; 33(4): 65-78, 2023 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-37098851

RESUMEN

OBJECTIVE: Statins are the first-choice therapy for dyslipidemia, but their effectiveness can be influenced by genetic polymorphisms. This study was conducted to assess the association of variants of the solute carrier anion transporter family 1B1 (SLCO1B1) gene, which encodes a transporter involving the hepatic clearance of the statins and their therapeutic efficacy. METHOD: A systematic review was performed on four electronic databases to identify relevant studies. The pooled mean difference with 95% confidence interval (CI) in percentage change of concentration of LDL-C, total cholesterol (TC), HDL-C, and triglycerides was calculated. Heterogeneity between studies and publication bias, subgroup analyses, and sensitivity analyses were also carried out using R software. RESULTS: Twenty-one studies on 24 365 participants and four variants [rs4149056 (c.521T>C), rs2306283 (c.388A>G), rs11045819 (c.463C>A), rs4363657 (g.89595T>C)] were analyzed. A statistically significant association was found between the LDL-C-lowering effectiveness and the rs4149056 and rs11045819 in the heterozygote model; and the rs4149056, rs2306283, and rs11045819 in the homozygote model. In the subgroup analyses, non-Asian populations, simvastatin, and pravastatin showed significant associations between LDL-C-lowering efficacy and the rs4149056 or rs2306283. Significant associations between the rs2306283 and HDL-C-increasing effectiveness were found in the homozygote model. Regarding TC-reducing, significant associations were observed in the heterozygote and homozygote models of the rs11045819. There was no heterogeneity and publication bias among most studies. CONCLUSION: SLCO1B1 variants can be used as signals to predict the statins' effectiveness.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas , Transportadores de Anión Orgánico , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , LDL-Colesterol , Polimorfismo de Nucleótido Simple/genética , Transportador 1 de Anión Orgánico Específico del Hígado/genética , Simvastatina/uso terapéutico , Transportadores de Anión Orgánico/genética
7.
Environ Res ; 227: 115800, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-37003549

RESUMEN

The considerable increase in world energy consumption owing to rising global population, intercontinental transportation and industrialization has posed numerous environmental concerns. Particularly, in order to meet the required electricity supply, thermal power plants for electricity generation are widely used in many countries. However, an annually excessive quantity of waste fly ash up to 1 billion tones was globally discarded from the combustion of various carbon-containing feedstocks in thermoelectricity plants. About half of the industrially generated fly ash is dumped into landfills and hence causing soil and water contamination. Nonetheless, fly ash still contains many valuable components and possesses outstanding physicochemical properties. Utilizing waste fly ash for producing value-added products has gained significant interests. Therefore, in this work, we reviewed the current implementation of fly ash-derived materials, namely, zeolite and geopolymer as efficient adsorbents for the environmental treatment of flue gas and polluted water. Additionally, the usage of fly ash as a catalyst support for the photodegradation of organic pollutants and reforming processes for the corresponding wastewater remediation and H2 energy generation is thoroughly covered. In comparison with conventional carbon-based adsorbents, fly ash-derived geopolymer and zeolite materials reportedly exhibited greater heavy metal ions removal and reached the maximum adsorption capacity of about 150 mg g-1. As a support for biogas reforming process, fly ash could enhance the activity of Ni catalyst with 96% and 97% of CO2 and CH4 conversions, respectively.


Asunto(s)
Restauración y Remediación Ambiental , Zeolitas , Ceniza del Carbón , Zeolitas/química , Agua , Carbono/química
8.
Chem Biodivers ; 20(12): e202301192, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37819841

RESUMEN

Epaltes australis Less. has been traditionally used to treat fever and snake bites, whereas Lindera myrrha (Lour.) Merr. is well-known for addressing colds, chest pain, indigestion, and worm infestations. This study marks the first report on the chemical compositions and biological potentials of essential oils extracted from the leaves of Epaltes australis and Lindera myrrha. Essential oils obtained by hydro-distillation were analysed using the GC/MS (gas chromatography-mass spectrometry). E. australis exhibited a predominant presence of non-terpenic compounds (46.3 %), with thymohydroquinone dimethyl ether as the major compound, constituting 44.2 % of the oil. L. myrrha leaf oil contained a good proportion of sesquiterpene hydrocarbons (56.8 %), with principal compounds including (E)-caryophyllene (22.2 %), ledene (9.7 %), selina-1,3,7(11)-trien-8-one (9.6 %), and α-pinene (7.0 %). Both essential oils exhibited antimicrobial activity against the bacteria Bacillus subtilis and Clostridium sporogenes, and Escherichia coli, and the fungus Aspergillus brasiliensis. L. myrrha leaf essential oil exhibited potent control over the yeast Saccharomyces cerevisiae with a MIC of 32 µg/mL. Additionally, L. myrrha leaf oil showed strong anti-inflammatory activity with an IC50 value of 15.20 µg/mL by inhibiting NO (nitric oxide) production in LPS (lipopolysaccharide)-stimulated RAW2647 murine macrophage cells. Regarding anti-tyrosinase activity, E. australis leaf oil showed the best monophenolase inhibition with the IC50 of 245.59 µg/mL, while L. myrrha leaf oil successfully inhibited diphenolase with the IC50 of 152.88 µg/mL. From molecular docking study, selina-1,3,7(11)-trien-8-one showed the highest affinity for both COX-2 (cyclooxygenase-2) and TNF-α (tumor necrosis factor-α) receptors. Hydrophobic interactions play a great role in the bindings of ligand-receptor complexes.


Asunto(s)
Antiinfecciosos , Lindera , Aceites Volátiles , Animales , Ratones , Aceites Volátiles/química , Monofenol Monooxigenasa , Simulación del Acoplamiento Molecular , Antiinfecciosos/farmacología , Hojas de la Planta/química , Antiinflamatorios/química , Pruebas de Sensibilidad Microbiana
9.
J Med Virol ; 94(10): 5061-5065, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35701340

RESUMEN

Human immunodeficiency virus (HIV) drug resistance increases mortality and morbidity and antiretroviral therapy (ART) costs. We describe Paraguay's first nationally representative survey on pretreatment drug resistance (PDR) conducted among persons who initiated or reinitiated ART in 2019. ​​​​We conducted a cross-sectional survey of antiretroviral (ARV) drug resistance in Paraguay in 2019. Participants were sampled at four comprehensive care clinics where 90% of patients with HIV in Paraguay initiate ART. Patients included were adults ≥18 years old who initiated first-line ART or reinitiated the same first-line ART regimen after ≥3 months of discontinuation. Of 208 patients, 93.8% had no prior ART exposure, 3.8% reinitiated the same regimen, 2.4% had unknown prior ART exposure; and 31.3% had a CD4 count <200 cells/µl. Mutations associated with resistance were present in 15.4% of patients. Mutations associated with resistance to nonnucleoside reverse transcriptase inhibitors (NNRTI) were present in 13.0% of patients, nucleoside reverse transcriptase inhibitors in 4.3%, and integrase inhibitors in 3.4%. Mutations associated with resistance to tenofovir were present in 1.0% of patients and emtricitabine/lamivudine in 1.4%. ​​Nearly one in six patients had PDR in Paraguay's first nationally representative sample. High NNRTI PDR prevalence underscores the need to accelerate the transition to dolutegravir-based first-line ART. The low PDR prevalence of tenofovir and emtricitabine is reassuring as these ARVs are part of the World Health Organization (WHO)-recommended oral pre-exposure prophylaxis regimen. The high proportion of individuals initiating ART at a late disease stage highlights the need to improve treatment linkage strategies and implement WHO rapid ART initiation recommendations.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , VIH-1 , Adolescente , Adulto , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Antirretrovirales/uso terapéutico , Estudios Transversales , Farmacorresistencia Viral/genética , Emtricitabina/uso terapéutico , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , VIH-1/genética , Humanos , Paraguay/epidemiología , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Tenofovir/uso terapéutico , Carga Viral
10.
AIDS Behav ; 26(3): 814-821, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34518938

RESUMEN

Youth aged 15-24 years comprise 48% of new HIV infections and 15% of persons living with HIV in Kisumu County, Kenya. We assessed factors associated with HIV infection among youth participating in the Community Health Initiative (CHI) implemented in an urban informal settlement in 2018. Predictors of HIV infection were assessed by multivariable logistic regression. CHI engaged 4,441 youth through community health campaigns and home-based HIV testing. HIV prevalence was 3.5% overall and 7.1% among young women aged 20-24. There were 24 youth newly identified as HIV-positive out of 157 total HIV-positive youth. HIV-positive status was positively associated with being female (aOR = 2.46; 95% CI 1.57, 3.84) and aged 20-24 (aOR = 2.40; 95% CI 1.52, 3.79), and inversely associated with secondary school education or higher (aOR = 0.27; 95% CI 0.16, 0.44). Our findings highlight the need for HIV prevention programs specially tailored for youth to further reduce new HIV infections in this priority population.


Asunto(s)
Síndrome de Inmunodeficiencia Adquirida , Infecciones por VIH , Adolescente , Adulto , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Prueba de VIH , Humanos , Kenia/epidemiología , Conducta Sexual , Adulto Joven
11.
Mol Biol Rep ; 49(9): 8859-8870, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35941418

RESUMEN

BACKGROUND: Hypoxic preconditioning (HP) is a stem cell preconditioning modality designed to augment the therapeutic effects of mesenchymal stem cells (MSCs). Although autophagy is expected to play a role in HP, very little is known regarding the relationship between HP and autophagy. METHODS AND RESULTS: The adipose-derived stem cell (ASC)-secretome obtained under normoxia (NCM) and ASC-secretome obtained under HP (HCM) were obtained by culturing ASCs for 24 h under normoxic (21% partial pressure of O2) and hypoxic (1% partial pressure of O2) conditions, respectively. Subsequently, to determine the in vivo effects of HCM, each secretome was injected into 70% partially hepatectomized mice, and liver specimens were obtained. HCM significantly reduced the apoptosis of thioacetamide-treated AML12 hepatocytes and promoted the autophagic processes of the cells (P < 0.05). Autophagy blockage by either bafilomycin A1 or ATG5 siRNA significantly abrogated the anti-apoptotic effect of HCM (P < 0.05), demonstrating that HCM exerts its anti-apoptotic effect by promoting autophagy. The effect of HCM - reduction of cell apoptosis and promotion of autophagic process - was also demonstrated in a mouse model. CONCLUSIONS: HP appears to induce ASCs to release a secretome with enhanced anti-apoptotic effects by promoting the autophagic process of ASCs.


Asunto(s)
Tejido Adiposo , Secretoma , Adipocitos , Tejido Adiposo/metabolismo , Animales , Autofagia , Humanos , Ratones , Células Madre
12.
Biochem Biophys Res Commun ; 553: 85-91, 2021 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-33765558

RESUMEN

Glucose-6-phosphate dehydrogenase is the first enzyme in the pentose phosphate pathway. The reaction catalyzed by the enzyme is considered to be the main source of reducing power for nicotinamide adenine dinucleotide phosphate (NADPH) and is a precursor of 5-carbon sugar used by cells. To uncover the structural features of the enzyme, we determined the crystal structures of glucose-6-phosphate dehydrogenase from Kluyveromyces lactis (KlG6PD) in both the apo form and a binary complex with its substrate glucose-6-phosphate. KlG6PD contains a Rossman-like domain for cofactor NADPH binding; it also presents a typical antiparallel ß sheet at the C-terminal domain with relatively the same pattern as those of other homologous structures. Moreover, our structural and biochemical analyses revealed that Lys153 contributes significantly to substrate G6P recognition. This study may provide insights into the structural variation and catalytic features of the G6PD enzyme.


Asunto(s)
Glucosafosfato Deshidrogenasa/química , Glucosafosfato Deshidrogenasa/metabolismo , Kluyveromyces/enzimología , Secuencia de Aminoácidos , Apoenzimas/química , Apoenzimas/genética , Apoenzimas/metabolismo , Sitios de Unión , Dominio Catalítico , Cristalografía por Rayos X , Glucosafosfato Deshidrogenasa/genética , Cinética , Modelos Moleculares , Mutagénesis , Relación Estructura-Actividad , Especificidad por Sustrato
13.
Stud Fam Plann ; 52(4): 557-570, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34766351

RESUMEN

In Kenya, adolescent pregnancy rates are high, contraception utilization is low, and adolescent sexuality is stigmatized. We describe how perceptions of sexuality and pregnancy stigma influence decision-making among adolescents in the informal settlements of Kisumu. We used purposive sampling to recruit 120 adolescent boys and girls aged 15-19 for focus group discussions. A semistructured interview guide was used to elicit social norms and community attitudes about sexual and reproductive health. We analyzed the data using the Framework Approach. The social stigma of adolescent sexuality and the related fear of pregnancy as an unambiguous marker of sexual activity emerged as main themes. This stigma led adolescents to fear social retribution but did not lead to more frequent contraception use due to additional stigma. The intensity of this fear was most acutely expressed by girls, leading some to seek unsafe, sometimes fatal, abortions, and to contemplate suicide. Fear of pregnancy outweighed fear of contracting HIV that was viewed as both treatable and less stigmatized. Our findings illustrate how fear of pregnancy among these adolescents is driven primarily by fears that their community will discover that they are sexually active. Interventions are urgently needed to address adolescent sexual stigma and to prevent negative outcomes.


Asunto(s)
Infecciones por VIH , Estigma Social , Adolescente , Femenino , Humanos , Kenia , Masculino , Embarazo , Conducta Sexual , Sexualidad , Caminata
14.
Int J Mol Sci ; 22(6)2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33799789

RESUMEN

It is challenging to overcome the low response rate of everolimus in the treatment of patients with hepatocellular carcinoma (HCC). To overcome this challenge, we combined everolimus with Ku0063794, the inhibitor of mTORC1 and mTORC2, to achieve higher anticancer effects. However, the precise mechanism for the synergistic effects is not clearly understood yet. To achieve this aim, the miRNAs were selected that showed the most significant variation in expression according to the mono- and combination therapy of everolimus and Ku0063794. Subsequently, the roles of specific miRNAs were determined in the processes of the treatment modalities. Compared to individual monotherapies, the combination therapy significantly reduced viability, increased apoptosis, and reduced autophagy in HepG2 cells. The combination therapy led to significantly lower expression of miR-4790-3p and higher expression of zinc finger protein225 (ZNF225)-the predicted target of miR-4790-3p. The functional study of miR-4790-3p and ZNF225 revealed that regarding autophagy, miR-4790-3p promoted it, while ZNF225 inhibited it. In addition, regarding apoptosis, miR-4790-3p inhibited it, while ZNF225 promoted it. It was also found that HCC tissues were characterized by higher expression of miR-4790-3p and lower expression of ZNF225; HCC tissues were also characterized by higher autophagic flux. We, thus, conclude that the potentiated anticancer effect of the everolimus and Ku0063794 combination therapy is strongly associated with reduced autophagy resulting from diminished expression of miR-4790-3p, as well as higher expression of ZNF225.


Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Everolimus/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , MicroARNs/genética , Morfolinas/farmacología , Pirimidinas/farmacología , Antineoplásicos/farmacología , Apoptosis/genética , Autofagia/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Sinergismo Farmacológico , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Proteína 1 de la Respuesta de Crecimiento Precoz/metabolismo , Inhibidores Enzimáticos/farmacología , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Diana Mecanicista del Complejo 1 de la Rapamicina/antagonistas & inhibidores , Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Diana Mecanicista del Complejo 2 de la Rapamicina/antagonistas & inhibidores , Diana Mecanicista del Complejo 2 de la Rapamicina/metabolismo
15.
J Environ Manage ; 280: 111652, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33229112

RESUMEN

Phosphorus (P) concentration beyond threshold limit can trigger eutrophication in stagnant water bodies nevertheless it is an indispensable macronutrient for aquatic life. Even in low P concentration (≤1 mg L-1), P can be detrimental for ecosystem's health, but this aspect has not been thoroughly investigated. The elimination of low P content is rather expensive or complex. Therefore, a unique and sustainable approach has been proposed in which valorized bivalve seashells can be used for the removal of low P content. Initially, acicular shaped aragonite particles (~21 µm) with an aspect ratio of around 21 have been synthesized through the wet carbonation process and used to treat aqueous solutions containing P in low concentration (P ≤ 1 mg L-1). Response surface methodology based Box-Behnken design has been employed for optimization study which revealed that with aragonite dosage (140 mg), equilibrium pH (~10.15), and temperature (45 °C), a phosphorus removal efficiency of ~97% can be obtained in 10 h. The kinetics and isotherm studies have also been carried out (within the range P ≤ 1 mg L-1) to investigate a probable removal mechanism. Also, aragonite demonstrates higher selectivity (>70%) towards phosphate with coexisting anions such as nitrate, chloride, sulfate, and carbonate. Through experimental data, elemental mapping, and molecular dynamic simulation, it has been observed that the removal mechanism involved a combination of electrostatic adsorption of Ca2+ ions on aragonite surface and chemical interaction between the calcium and phosphate ions. The present work demonstrates a sustainable and propitious potential of seashell derived aragonite for the removal of low P content in aqueous solution along with its unconventional mechanistic approach.


Asunto(s)
Carbonato de Calcio , Contaminantes Químicos del Agua , Adsorción , Exoesqueleto , Animales , Ecosistema , Concentración de Iones de Hidrógeno , Cinética , Fosfatos , Fósforo , Agua
16.
BMC Infect Dis ; 20(1): 248, 2020 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-32216752

RESUMEN

BACKGROUND: Understanding factors driving virological failure, including the contribution of HIV drug resistance mutations (DRM), is critical to ensuring HIV treatment remains effective. We examine the contribution of drug resistance mutations for low viral suppression in HIV-positive participants in a population-based sero-prevalence survey in rural South Africa. METHODS: We conducted HIV drug resistance genotyping and ART analyte testing on dried blood spots (DBS) from HIV-positive adults participating in a 2014 survey in North West Province. Among those with virologic failure (> 5000 copies/mL), we describe frequency of DRM to protease inhibitors (PI), nucleoside reverse transcriptase inhibitors (NRTI), and non-nucleoside reverse transcriptase inhibitors (NNRTI), report association of resistance with antiretroviral therapy (ART) status, and assess resistance to first and second line therapy. Analyses are weighted to account for sampling design. RESULTS: Overall 170 DBS samples were assayed for viral load and ART analytes; 78.4% of men and 50.0% of women had evidence of virologic failure and were assessed for drug resistance, with successful sequencing of 76/107 samples. We found ≥1 DRM in 22% of participants; 47% were from samples with detectable analyte (efavirenz, nevirapine or lopinavir). Of those with DRM and detectable analyte, 60% showed high-level resistance and reduced predicted virologic response to ≥1 NRTI/NNRTI typically used in first and second-line regimens. CONCLUSIONS: DRM and predicted reduced susceptibility to first and second-line regimens were common among adults with ART exposure in a rural South African population-based sample. Results underscore the importance of ongoing virologic monitoring, regimen optimization and adherence counseling to optimize durable virologic suppression.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Farmacorresistencia Viral/genética , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , VIH/efectos de los fármacos , VIH/genética , Carga Viral/efectos de los fármacos , Adolescente , Adulto , Estudios de Cohortes , Pruebas con Sangre Seca , Femenino , Genotipo , Infecciones por VIH/virología , Seroprevalencia de VIH , Humanos , Masculino , Persona de Mediana Edad , Mutación , Prevalencia , Población Rural , Sudáfrica/epidemiología , Adulto Joven
17.
Int J Mol Sci ; 21(17)2020 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-32854415

RESUMEN

Here, we provide the possibility of a novel chemotherapeutic agent against gastric cancer cells, comprising the combination of 5-fluorouracil (5-FU) and a mitochondria-targeting self-assembly peptide, which is a phenylalanine dipeptide with triphenyl phosphonium (Mito-FF). The anticancer effects and mechanisms of 5-FU and Mito-FF, individually or in combination, were compared through both in vitro and in vivo models of gastric cancer. Our experiments consistently demonstrated that the 5-FU and Mito-FF combination therapy was superior to monotherapy with either, as manifested by both higher reduction of proliferation as well as an induction of apoptotic cell death. Interestingly, we found that combining 5-FU with Mito-FF leads to a significant increase of reactive oxygen species (ROS) and reduction of antioxidant enzymes in gastric cancer cells. Moreover, the inhibition of ROS abrogated the pro-apoptotic effects of combination therapy, suggesting that enhanced oxidative stress could be the principal mechanism of the action of combination therapy. We conclude that the combination of 5-FU and Mito-FF exerts potent antineoplastic activity against gastric cancer cells, primarily by promoting ROS generation and suppressing the activities of antioxidant enzymes.


Asunto(s)
Dipéptidos/administración & dosificación , Fluorouracilo/administración & dosificación , Mitocondrias/metabolismo , Neoplasias Gástricas/tratamiento farmacológico , Animales , Catalasa/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Dipéptidos/química , Dipéptidos/farmacología , Sinergismo Farmacológico , Fluorouracilo/farmacología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Glutatión Peroxidasa/genética , Humanos , Masculino , Ratones , Mitocondrias/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Superóxido Dismutasa/genética , Ensayos Antitumor por Modelo de Xenoinjerto
18.
Int J Mol Sci ; 21(5)2020 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-32143463

RESUMEN

This paper aims to validate if intrapancreatic injection of penicillin G can enhance hardness and suture holding capacity (SHC) of the pancreas through prompting the fibrosis process. Soft pancreatic texture is constantly mentioned as one of the most contributory predictors of postoperative pancreatic fistula (POPF). Soft pancreas has poor SHC and higher incidence of parenchymal tearing, frequently leading to POPF. From a library of 114 antibiotic compounds, we identified that penicillin G substantially enhanced pancreatic hardness and SHC in experimental mice. Specifically, we injected penicillin G directly into the pancreas. On determined dates, we measured the pancreatic hardness and SHC, respectively, and performed molecular and histological examinations for estimation of the degree of fibrosis. The intrapancreatic injection of penicillin G activated human pancreatic stellate cells (HPSCs) to produce various fibrotic materials such as transforming growth factor-ß1 (TGF-ß1) and metalloproteinases-2. The pancreatic hardness and SHC were increased to the maximum at the second day after injection and then it gradually subsided demonstrating its reversibility. Pretreatment of mice with SB431542, an inhibitor of the TGF-ß1 receptor, before injecting penicillin G intrapancreatically, significantly abrogated the increase of both pancreatic hardness and SHC caused by penicillin G. This suggested that penicillin G promotes pancreatic fibrosis through the TGF-ß1 signaling pathway. Intrapancreatic injection of penicillin G promotes pancreatic hardness and SHC by enhancing pancreatic fibrosis. We thus think that penicillin G could be utilized to prevent and minimize POPF, after validating its actual effectiveness and safety by further studies.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Páncreas/efectos de los fármacos , Páncreas/cirugía , Fístula Pancreática/prevención & control , Penicilina G/administración & dosificación , Complicaciones Posoperatorias/prevención & control , Animales , Antibacterianos/administración & dosificación , Benzamidas/farmacología , Dioxoles/farmacología , Modelos Animales de Enfermedad , Fibrosis , Humanos , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Ratones , Ratones Endogámicos BALB C , Fístula Pancreática/etiología , Células Estrelladas Pancreáticas/efectos de los fármacos , Células Estrelladas Pancreáticas/metabolismo , Periodo Posoperatorio , Receptores de Factores de Crecimiento Transformadores beta/antagonistas & inhibidores , Factor de Crecimiento Transformador beta1/metabolismo
19.
J Transl Med ; 17(1): 195, 2019 06 10.
Artículo en Inglés | MEDLINE | ID: mdl-31182117

RESUMEN

BACKGROUND: Although methyl-tertiary butyl ether (MTBE) is the only clinical topical agent for gallstone dissolution, its use is limited by its side effects mostly arising from a relatively low boiling point (55 °C). In this study, we developed the gallstone-dissolving compound containing an aromatic moiety, named 2-methoxy-6-methylpyridine (MMP) with higher boiling point (156 °C), and compared its effectiveness and toxicities with MTBE. METHODS: The dissolubility of MTBE and MMP in vitro was determined by placing human gallstones in glass containers with either solvent and, then, measuring their dry weights. Their dissolubility in vivo was determined by comparing the weights of solvent-treated gallstones and control (dimethyl sulfoxide)-treated gallstones, after directly injecting each solvent into the gallbladder in hamster models with cholesterol and pigmented gallstones. RESULTS: In the in vitro dissolution test, MMP demonstrated statistically higher dissolubility than did MTBE for cholesterol and pigmented gallstones (88.2% vs. 65.7%, 50.8% vs. 29.0%, respectively; P < 0.05). In the in vivo experiments, MMP exhibited 59.0% and 54.3% dissolubility for cholesterol and pigmented gallstones, respectively, which were significantly higher than those of MTBE (50.0% and 32.0%, respectively; P < 0.05). The immunohistochemical stains of gallbladder specimens obtained from the MMP-treated hamsters demonstrated that MMP did not significantly increase the expression of cleaved caspase 9 or significantly decrease the expression of proliferation cell nuclear antigen. CONCLUSIONS: This study demonstrated that MMP has better potential than does MTBE in dissolving gallstones, especially pigmented gallstones, while resulting in lesser toxicities.


Asunto(s)
Cálculos Biliares/tratamiento farmacológico , Fármacos Gastrointestinales/administración & dosificación , Piridinas/administración & dosificación , Solventes/administración & dosificación , Administración Tópica , Animales , Células CHO , Células Cultivadas , Chlorocebus aethiops , Cricetinae , Cricetulus , Evaluación Preclínica de Medicamentos/métodos , Embrión no Mamífero , Femenino , Cálculos Biliares/patología , Fármacos Gastrointestinales/efectos adversos , Humanos , Mesocricetus , Ratones , Ratones Endogámicos ICR , Células 3T3 NIH , Piridinas/efectos adversos , Solventes/efectos adversos , Células Vero , Pez Cebra
20.
AIDS Behav ; 23(7): 1846-1857, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30306435

RESUMEN

As evidence of the safety and effectiveness of HIV pre-exposure prophylaxis (PrEP) has grown, so has attention to the views of prospective users and providers. However, far less attention has been paid to understanding the perspectives of other stakeholders in the rollout of PrEP access programs. We conducted 21 semi-structured qualitative interviews in 2017 with key stakeholders working across the policy, advocacy, research and/or clinical dimensions of the Australian HIV response, before federal support for a subsidised access scheme was achieved. Our analysis explored three areas of shared concern: who is a suitable candidate for PrEP; why are disparities in PrEP access important; and how can disparities be addressed? In examining how this diverse group of professionals grappled with the challenges of promoting 'equitable access' to PrEP in an increasingly resource rationed health system, we can see how the principles believed to underpin the Australian response to HIV were both reaffirmed and challenged through this period of significant change.


Asunto(s)
Infecciones por VIH/prevención & control , Equidad en Salud , Promoción de la Salud/estadística & datos numéricos , Profilaxis Pre-Exposición , Adulto , Australia/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos
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