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1.
Adv Nutr ; : 100292, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39299839

RESUMEN

The effect of nonnutritive sweeteners (NNSs) on the body mass index [BMI (in kg/m2)] of children and adolescents remains unclear despite rising consumption. Detailed systematic evaluations are warranted. We aimed to summarize evidence on NNS consumption and BMI sex- and age-specific absolute changes (kg/m2) in pediatric populations, by NNS type, study design, duration, analysis type, conflicts of interest (COI), geographical region, age, sex, and baseline BMI. We searched randomized controlled trials (RCTs) and prospective cohort studies in children (2-9 y), adolescents (10-24 y), and young adults (20-24 y). Pooled estimates derived from random-effects meta-analysis for BMI changes, and the evidence quality was evaluated overall and by subgroup. From 2789 results, we included 4 RCTs [n = 1372; mean follow-up = 42.6 wk (standard deviation = 18.4); 2 (50%) with COI], and 8 prospective cohort studies [n = 35,340; median follow-up 2.5 y (interquartile range = 1.7-6.3), 2 (25%) with COI]. No identified studies evaluated NNS in food, NNS beverages compared with water, or participants aged 20-24 y. Random allocation to NNS beverages (25-2400 mg/d, from beverages) showed less BMI gain [mean difference = -0.114 kg/m2 (95% confidence interval [CI]: -0.207, -0.021); I2 = 87.02%] compared with sugar-sweetened beverages (SSBs). Stratified estimates resulted in less BMI gain in adolescents, participants with baseline obesity, consumers of mixed NNS, longer trials, and trials without COI. Pooled estimates from prospective cohorts showed a nonsignificant association between NNS beverages and BMI gain [0.05 kg/m2 (95% CI: -0.03, 0.13); I2 = 75.06%; per daily 355 mL serving]. Stratified estimates remained consistent. Removing studies with COI attenuated estimates. Evidence had low to moderate quality. In summary, pooled results from RCTs comparing NNS beverages compared with SSBs showed less BMI gain in adolescents with obesity. Meta-analyses of long-term cohort studies did not display a significant association between NNS beverages and BMI changes. This trial was registered at PROSPERO as CRD42022352284.

2.
Pharmaceuticals (Basel) ; 17(8)2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39204156

RESUMEN

In this work, the leaves of K. tomentosa were macerated with hexane, chloroform, and methanol, respectively. The phytochemical profiles of hexane and chloroform extracts were unveiled using GC/MS, whereas the chemical composition of the methanol extract was analyzed using UPLC/MS/MS. The antibacterial activity of extracts was determined against gram-positive and gram-negative strains through the minimal inhibitory concentration assay, and in silico studies were implemented to analyze the interaction of phytoconstituents with bacterial peptides. The antioxidant property of extracts was assessed by evaluating their capacity to scavenge DPPH, ABTS, and H2O2 radicals. The toxicity of the extracts was recorded against Artemia salina nauplii and Caenorhabditis elegans nematodes. Results demonstrate that the hexane and chloroform extracts contain phytosterols, triterpenes, and fatty acids, whereas the methanol extract possesses glycosidic derivatives of quercetin and kaempferol together with sesquiterpene lactones. The antibacterial performance of extracts against the cultured strains was appraised as weak due to their MIC90 values (>500 µg/mL). As antioxidants, treatment with extracts executed high and moderate antioxidant activities within the range of 50-300 µg/mL. Extracts did not decrease the viability of A. salina, but they exerted a high toxic effect against C. elegans during exposure to treatment. Through in silico modeling, it was recorded that the flavonoids contained in the methanol extract can hamper the interaction of the NAM/NAG peptide, which is of great interest since it determines the formation of the peptide wall of gram-positive bacteria. This study reports for the first time the biological activities and phytochemical content of extracts from K. tomentosa and proposes a possible antibacterial mechanism of glycosidic derivatives of flavonoids against gram-positive bacteria.

3.
Front Genet ; 15: 1421870, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39130748

RESUMEN

Introduction: Genetic variants that control dopamine have been associated with obesity in children through loss of control of satiety and impulses, the manifestation of addictive eating behaviors, and specific personality traits. The variants include FTO-rs9939609 and the MAO-A 30 pb u-VNTR low-transcription alleles (LTA). Objective: To evaluate the genetic association of FTO-rs9939609 and the MAO-A LTA, along with personality traits and eating behavior with obesity in Mayan children from Mexico. Methods: We cross-sectionally evaluated 186 children (70 with obesity and 116 with normal weight) 6-12 years old from Yucatan, Mexico. Nutritional status was defined with body mass index (BMI) percentiles. Personality traits were evaluated with the Conners and TMCQ tests; eating behavior was evaluated with the CEBQ test. Genotyping with real-time PCR and TaqMan probes was used for FTO-rs9939609, whereas PCR amplification was used for MAO-A u-VNTR. Results: High-intensity pleasure (p = 0.013) and moderate appetite (p = 0.032) differed according to nutritional status. Heterozygous FTO-rs9939609 T/A children showed higher mean scores of low-intensity pleasure (p = 0.002) and moderate appetite (p = 0.027) than homozygous T/T. Hemizygous boys having MAO-A LTA showed significantly higher mean scores of anxiety (p = 0.001) and impulsivity (p = 0.008). In multivariate models, only LTA alleles of MAO-A explained obesity in boys (OR = 4.44; 95% CI = 1.18-16.63). Conclusion: In the present study, MAO-A u-VNTR alleles were associated with obesity in multivariate models only in boys. These alleles might also have a role in personality traits such as anxiety and impulsivity, which secondly contribute to developing obesity in Mayan boys.

4.
Artículo en Inglés | MEDLINE | ID: mdl-39133335

RESUMEN

The acquisition of an acoustic template is a fundamental component of vocal imitation learning, which is used to refine innate vocalizations and develop a species-specific song. In the absence of a model, birds fail to develop species typical songs. In zebra finches (Taeniopygia guttata), tutored birds produce songs with a stereotyped sequence of distinct acoustic elements, or notes, which form the song motif. Songs of untutored individuals feature atypical acoustic and temporal structure. Here we studied songs and associated respiratory patterns of tutored and untutored male zebra finches to investigate whether similar acoustic notes influence the sequence of song elements. A subgroup of animals developed songs with multiple acoustically similar notes that are produced with alike respiratory motor gestures. These birds also showed increased syntactic variability in their adult motif. Sequence variability tended to occur near song elements which showed high similarity in acoustic structure and underlying respiratory motor gestures. The duration and depth of the inspirations preceding the syllables where syntactic variation occurred did not allow prediction of the following sequence of notes, suggesting that the varying duration and air requirement of the following expiratory pulse is not predictively encoded in the motor program. This study provides a novel method for calculation of motor/acoustic similarity, and the results of this study suggest that the note is a fundamental acoustic unit in the organization of the motif and could play a role in the neural code for song syntax.

5.
Biomolecules ; 14(7)2024 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-39062496

RESUMEN

In this work, the hexane, chloroform, and methanol extracts from Kalanchoe fedtschenkoi were utilized to green-synthesize silver nanoparticles (Kf1-, Kf2-, and Kf3-AgNPs). The Kf1-, Kf2-, and Kf3-AgNPs were characterized by spectroscopy and microscopy techniques. The antibacterial activity of AgNPs was studied against bacteria strains, utilizing the microdilution assay. The DPPH and H2O2 assays were considered to assess the antioxidant activity of AgNPs. The results revealed that Kf1-, Kf2-, and Kf3-AgNPs exhibit an average diameter of 39.9, 111, and 42 nm, respectively. The calculated ζ-potential of Kf1-, Kf2-, and Kf3-AgNPs were -20.5, -10.6, and -7.9 mV, respectively. The UV-vis analysis of the three samples demonstrated characteristic absorption bands within the range of 350-450 nm, which confirmed the formation of AgNPs. The FTIR analysis of AgNPs exhibited a series of bands from 3500 to 750 cm-1, related to the presence of extracts on their surfaces. SEM observations unveiled that Kf1- and Kf2-AgNPs adopted structural arrangements related to nano-popcorns and nanoflowers, whereas Kf3-AgNPs were spherical in shape. It was determined that treatment with Kf1-, Kf2-, and Kf3-AgNPs was demonstrated to inhibit the growth of E. coli, S. aureus, and P. aeruginosa in a dose-dependent manner (50-300 µg/mL). Within the same range, treatment with Kf1-, Kf2-, and Kf3-AgNPs decreased the generation of DPPH (IC50 57.02-2.09 µg/mL) and H2O2 (IC50 3.15-3.45 µg/mL) radicals. This study highlights the importance of using inorganic nanomaterials to improve the biological performance of plant extracts as an efficient nanotechnological approach.


Asunto(s)
Antibacterianos , Antioxidantes , Tecnología Química Verde , Kalanchoe , Nanopartículas del Metal , Pruebas de Sensibilidad Microbiana , Extractos Vegetales , Plata , Nanopartículas del Metal/química , Plata/química , Plata/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/síntesis química , Kalanchoe/química , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/síntesis química , Compuestos de Bifenilo/antagonistas & inhibidores , Compuestos de Bifenilo/química , Picratos/antagonistas & inhibidores , Picratos/química , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Peróxido de Hidrógeno
6.
Pathologica ; 116(3): 170-175, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38979591

RESUMEN

Embryonal tumors with multilayered rosettes (ETMR) are highly aggressive and therapy-resistant pediatric central nervous system (CNS) tumors that have three histological patters: embryonal tumor with abundant neuropil and true rosettes, ependymoblastoma, and medulloepithelioma. We present a case of ETMR in an 18-year-old woman with DICER1 syndrome. This report confirms the important role of DNA-methylation analysis in the classification of CNS embryonal tumors and the importance of investigating somatic and germline DICER1 mutations in all CNS embryonal tumors.


Asunto(s)
ARN Helicasas DEAD-box , Neoplasias de Células Germinales y Embrionarias , Ribonucleasa III , Humanos , Femenino , Ribonucleasa III/genética , ARN Helicasas DEAD-box/genética , Adolescente , Neoplasias de Células Germinales y Embrionarias/genética , Neoplasias de Células Germinales y Embrionarias/patología , Metilación de ADN
7.
Plants (Basel) ; 13(12)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38931016

RESUMEN

Carotenoids constitute compounds of significant biological interest due to their multiple biological activities, such as antimicrobial, anticancer, antiadipogenic, antidiabetic, and antioxidant properties. Metabolic syndrome (MetS) comprehends a series of metabolic abnormalities (e.g., hypertension, obesity, and atherogenic dyslipidemia) that can affect children, adolescents, and the elderly. The treatment of MetS involves numerous medications, which, despite their efficacy, pose challenges due to prolonged use, high costs, and various side effects. Carotenoids and their derivatives have been proposed as alternative treatments to MetS because they reduce serum triglyceride concentrations, promote insulin response, inhibit adipogenesis, and downregulate angiotensin-converting enzyme activity. However, carotenoids are notably sensitive to pH, light exposure, and temperature. This review addresses the activity of carotenoids such as lycopene, lutein, fucoxanthin, astaxanthin, crocin, and ß-carotene towards MetS. It includes a discussion of sources, extraction methods, and characterization techniques for analyzing carotenoids. Encapsulation approaches are critically reviewed as alternatives to prevent degradation and improve the biological performance of carotenoids. A brief overview of the physiopathology and epidemiology of the diseases, including MetS, is also provided.

8.
J Glaucoma ; 33(10): 794-800, 2024 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-38767514

RESUMEN

PRCIS: Ahmed glaucoma valve implantation by residents showed similar complications, success, and failure rates, regardless of their level of expertise. Training programs must encourage ophthalmologists to perform this surgery to enhance competence in their future practices. PURPOSE: To describe outcomes of resident-performed Ahmed valve implantation over a 5-year period. METHODS: In this cross-sectional observational study we retrospectively reviewed the medical records of patients who underwent resident-performed Ahmed glaucoma valve implantation over a 5-year period. The main outcomes were the number of surgeries performed by first-year, second-year, and third-year residents, intraoperative, and postoperative complications, and the association of level of training with outcomes and complications. RESULTS: Totally, 160 eyes were included, with a mean age of 53.8±15.4 years, 63% were men. The most frequent type of glaucoma was neovascular glaucoma (67.5%). Mean follow-up was 23.2±19.6 months. Residents of higher years performed more surgeries and no relationship was found between the surgeon's level of training and type of glaucoma operated on. After the surgical procedure, significant changes in best-corrected visual acuity were noted in surgeries performed by third-year residents ( P =0.04). Intraocular pressure and number of medications were significantly reduced in all groups ( P =0.01). Complications were registered in 60 eyes; the most frequent being the presence of a transient flat anterior chamber (27.45%). CONCLUSIONS: There were no significant differences in terms of IOP control and the number of complications in the 3 groups. There was no significant association between the resident's experience and the outcomes of the surgery. The Ahmed valve implant is a procedure that appears to have similar results in surgeons with different levels of training.


Asunto(s)
Competencia Clínica , Implantes de Drenaje de Glaucoma , Glaucoma , Internado y Residencia , Presión Intraocular , Oftalmología , Complicaciones Posoperatorias , Implantación de Prótesis , Agudeza Visual , Humanos , Femenino , Masculino , Estudios Retrospectivos , Persona de Mediana Edad , Estudios Transversales , Presión Intraocular/fisiología , Agudeza Visual/fisiología , Anciano , Resultado del Tratamiento , Glaucoma/cirugía , Glaucoma/fisiopatología , Adulto , Oftalmología/educación , Educación de Postgrado en Medicina/métodos , Complicaciones Intraoperatorias , Estudios de Seguimiento
9.
Biomater Sci ; 12(8): 2108-2120, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38450552

RESUMEN

The antioxidant capabilities of nanoparticles are contingent upon various factors, including their shape, size, and chemical composition. Herein, novel Nd-doped CeO2 nanoparticles were synthesized and the neodymium content was varied to investigate the synergistic impact on the antioxidant properties of CeO2 nanoparticles. Incorporating Nd3+ induced changes in lattice parameters and significantly altered the morphology from nanoparticles to nanorods. The biological activity of Nd-doped CeO2 was examined against pathogenic bacterial strains, breast cancer cell lines, and antioxidant models. The antibacterial and anticancer activities of nanoparticles were not observed, which could be associated with the Ce3+/Ce4+ ratio. Notably, the incorporation of neodymium improved the antioxidant capacity of CeO2. Machine learning techniques were employed to forecast the antioxidant activity to enhance understanding and predictive capabilities. Among these models, the random forest model exhibited the highest accuracy at 96.35%, establishing it as a robust computational tool for elucidating the biological behavior of Nd-doped CeO2 nanoparticles. This study presents the first exploration of the influence of Nd3+ on the structural, optical, and biological attributes of CeO2, contributing valuable insights and extending the application of machine learning in predicting the therapeutic efficacy of inorganic nanomaterials.


Asunto(s)
Nanopartículas , Nanoestructuras , Antioxidantes/farmacología , Antioxidantes/química , Neodimio , Nanopartículas/química , Antibacterianos/farmacología , Antibacterianos/química
10.
Antioxidants (Basel) ; 13(2)2024 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-38397812

RESUMEN

This study used a sonochemical synthesis method to prepare (La, Sm)-doped ZnO nanoparticles (NPs). The effect of incorporating these lanthanide elements on the structural, optical, and morphological properties of ZnO-NPs was analyzed. The cytotoxicity and the reactive oxygen species (ROS) generation capacity of ZnO-NPs were evaluated against breast (MCF7) and colon (HT29) cancer cell lines. Their antioxidant activity was analyzed using a DPPH assay, and their toxicity towards Artemia salina nauplii was also evaluated. The results revealed that treatment with NPs resulted in the death of 10.559-42.546% and 18.230-38.643% of MCF7 and HT29 cells, respectively. This effect was attributed to the ability of NPs to downregulate ROS formation within the two cell lines in a dose-dependent manner. In the DPPH assay, treatment with (La, Sm)-doped ZnO-NPs inhibited the generation of free radicals at IC50 values ranging from 3.898 to 126.948 µg/mL. Against A. salina nauplii, the synthesized NPs did not cause death nor induce morphological changes at the tested concentrations. A series of machine learning (ML) models were used to predict the biological performance of (La, Sm)-doped ZnO-NPs. Among the designed ML models, the gradient boosting model resulted in the greatest mean absolute error (MAE) (MAE 9.027, R2 = 0.86). The data generated in this work provide innovative insights into the influence of La and Sm on the structural arrangement and chemical features of ZnO-NPs, together with their cytotoxicity, antioxidant activity, and in vivo toxicity.

11.
Future Microbiol ; 18: 1147-1157, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37850348

RESUMEN

Aim: The present study was designed to evaluate the clinical characteristics of COVID-19 and mortality-associated factors during the first year of the pandemic in patients from southeastern Mexico. Patient & methods: A total of 953 records from patients with COVID-19 were cross-sectionally studied in a primary care hospital in southeast Mexico between 2020 and 2021. Results: The prevalent symptoms were fever (78.6%), cough (80.5%) and headache (82.8%) and dyspnea reached 13.5%. The mortality rate was 7.63% and the clinical variables associated with it were age >60 years, hypertension, severe disease, radiographic pneumonia, days to diagnosis and having two Mayan surnames. Conclusion: Future health strategies should consider age, comorbidities, disease severity, clinical manifestations and possessing ethnicity of risk (i.e., Mayan genetic background).


Asunto(s)
COVID-19 , Humanos , Persona de Mediana Edad , COVID-19/epidemiología , SARS-CoV-2 , Pandemias , México/epidemiología , Comorbilidad
12.
Plants (Basel) ; 12(10)2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37653861

RESUMEN

In this study, the leaves of Kalanchoe fedtschenkoi were consecutively macerated with hexane, chloroform, and methanol. These extracts were used to assess the bioactivities of the plant. The antimicrobial activity was tested against a panel of Gram-positive and -negative pathogenic bacterial and fungal strains using the microdilution method. The cytotoxicity of K. fedtschenkoi extracts was investigated using human-derived macrophage THP-1 cells through the MTT assay. Finally, the anti-inflammatory activity of extracts was studied using the same cell line by measuring the secretion of IL-10 and IL-6. The phytoconstituents of hexane and chloroform extracts were evaluated using gas chromatography-mass spectrometry (GC/MS). In addition, high-performance liquid chromatography (HPLC) was used to study the phytochemical content of methanol extract. The total flavonoid content (TFC) of methanol extract is also reported. The chemical composition of K. fedtschenkoi extracts was evaluated using Fourier-transform infrared spectroscopy (FTIR). Results revealed that the chloroform extract inhibited the growth of Pseudomonas aeruginosa at 150 µg/mL. At the same concentration, methanol extract inhibited the growth of methicillin-resistant Staphylococcus aureus (MRSA). Regarding their cytotoxicity, the three extracts were highly cytotoxic against the tested cell line at IC50 < 3 µg/mL. In addition, the chloroform extract significantly stimulated the secretion of IL-10 at 50 µg/mL (p < 0.01). GC/MS analyses revealed that hexane and chloroform extracts contain fatty acids, sterols, vitamin E, and triterpenes. The HPLC analysis demonstrated that methanol extract was constituted by quercetin and kaempferol derivatives. This is the first report in which the bioactivities and chemical profiles of K. fedtschenkoi are assessed for non-polar and polar extracts.

13.
Plants (Basel) ; 12(17)2023 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-37687382

RESUMEN

In this work, bulb extracts of Tigridia vanhouttei were obtained by maceration with solvents of increasing polarity. The extracts were evaluated against a panel of pathogenic bacterial and fungal strains using the minimal inhibitory concentration (MIC) assay. The cytotoxicity of the extracts was tested against two cell lines (THP-1 and A549) using the MTT assay. The anti-inflammatory activity of the extracts was evaluated in THP-1 cells by measuring the secretion of pro-inflammatory (IL-6 and TNF-α) and anti-inflammatory (IL-10) cytokines by ELISA. The chemical composition of the extracts was recorded by FTIR spectroscopy, and their chemical profiles were evaluated using GC-MS. The results revealed that only hexane extract inhibited the growth of the clinical isolate of Pseudomonas aeruginosa at 200 µg/mL. Against THP-1 cells, hexane and chloroform extracts were moderately cytotoxic, as they exhibited LC50 values of 90.16, and 46.42 µg/mL, respectively. Treatment with methanol extract was weakly cytotoxic at LC50 443.12 µg/mL against the same cell line. Against the A549 cell line, hexane, chloroform, and methanol extracts were weakly cytotoxic because of their LC50 values: 294.77, 1472.37, and 843.12 µg/mL. The FTIR analysis suggested the presence of natural products were confirmed by carboxylic acids, ketones, hydroxyl groups, or esters. The GC-MS profile of extracts revealed the presence of phytosterols, tetracyclic triterpenes, multiple fatty acids, and sugars. This report confirms the antimicrobial, cytotoxic, and anti-inflammatory activities of T. vanhouttei.

14.
Animals (Basel) ; 13(16)2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37627338

RESUMEN

With the aim of evaluating the effect of combining an antibiotic ionophore with plant extracts and probiotics on the productive efficiency (performance and carcass) during the last phase of lamb fattening, 24 Pelibuey × Katahdin male lambs (38.47 ± 3.92 kg, initial weight) were fed with a high-energy diet during for 56 days, and assigned, under a complete randomized block design experiment to one of the following supplement treatments: (1) 28 mg of monensin/kg diet DM supplemented alone (MON), (2) combination of MON plus 2 g/kg diet of a product contained Bacillus subtilis 2.2 × 108 CFU kg diet DM (MON + BS), (3) combination of MON + BS plus 300 mg essential oils/kg diet DM (MON + BS + EO), and (4) BS alone. At the end of the feeding trial (56-d), lambs were slaughtered and carcass variables were measured. Compared to the rest of the treatments, combining MON with BS improved dietary NE by 3.4% and the efficiency of utilization of dietary energy consumed. Inclusion of EO in the MON + BS combination resulted in a similar average daily weight gain (ADG) and feed efficiency (GF) when compared with MON + BS, but showed a lower dietary net energy (NE), hot carcass weight, and dressing percentage. Lambs receiving BS alone showed greater average ADG and dry matter intake (DMI) than lambs receiving MON + BS + EO, but similar feed GF and dietary NE. There were no treatment effects on tissue composition, whole cut, or visceral organ mass. It was concluded that combining probiotics with the ionophore monensin can improve the efficiency of dietary energy utilization in the last phase of finishing. Probiotics supplemented alone result in greater ADG without a difference in dietary energy efficiency when compared with MON alone. Inclusion of EO in the MON + BS combination did not show advantages; on the contrary, it reduced carcass weight and dressing percentage. It is necessary to further research the potential complementary effects of combining diverse sources of natural additives with synthetic antibiotics.

15.
Front Microbiol ; 14: 1179607, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37502399

RESUMEN

Hydrogen is considered one of the key enablers of the transition towards a sustainable and net-zero carbon economy. When produced from renewable sources, hydrogen can be used as a clean and carbon-free energy carrier, as well as improve the sustainability of a wide range of industrial processes. Photobiological hydrogen production is considered one of the most promising technologies, avoiding the need for renewable electricity and rare earth metal elements, the demands for which are greatly increasing due to the current simultaneous electrification and decarbonization goals. Photobiological hydrogen production employs photosynthetic microorganisms to harvest solar energy and split water into molecular oxygen and hydrogen gas, unlocking the long-pursued target of solar energy storage. However, photobiological hydrogen production has to-date been constrained by several limitations. This review aims to discuss the current state-of-the art regarding hydrogenase-driven photobiological hydrogen production. Emphasis is placed on engineering strategies for the expression of improved, non-native, hydrogenases or photosynthesis re-engineering, as well as their combination as one of the most promising pathways to develop viable large-scale hydrogen green cell factories. Herein we provide an overview of the current knowledge and technological gaps curbing the development of photobiological hydrogenase-driven hydrogen production, as well as summarizing the recent advances and future prospects regarding the expression of non-native hydrogenases in cyanobacteria and green algae with an emphasis on [FeFe] hydrogenases.

16.
Beilstein J Nanotechnol ; 14: 522-534, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37152474

RESUMEN

In the present work, the bottom-up fabrication of biohybrid materials using a nanoarchitectonics approach has been applied to entrap living cells. Unicellular microorganisms, that is, cyanobacteria and yeast cells, have been immobilized in silica and silicate-based substrates organized as nanostructured materials. In a first attempt, matrices based on bionanocomposites of chitosan and alginate incorporating sepiolite clay mineral and shaped as films, beads, or foams have been explored for the immobilization of cyanobacteria. It has been observed that this type of biohybrid substrates leads to serious problems regarding the long-time survival of the encapsulated microorganisms. Alternative procedures using silica-based matrices with low sodium content, generated by sol-gel methods, as well as pre-synthesised yolk-shell bionanohybrids have been studied subsequently. Optical microscopy and SEM confirm that the silica shell microstructures provide a reduced contact between cells. The inorganic matrix increases the survival of the cells and maintains their bioactivity. Thus, the encapsulation efficiency is improved compared to the approach using a direct contact of cells in a silica matrix. Encapsulated yeast produced ethanol over a period of several days, pointing out the useful biocatalytic potential of the approach and suggesting further optimization of the present protocols.

17.
Indian J Ophthalmol ; 71(5): 1966-1971, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37203066

RESUMEN

Purpose: To evaluate the prevalence of hypertensive phase (HP) and failure in patients who underwent Ahmed Glaucoma Valve (AGV) implantation and identify the possible risk factors for both HP and failure. Methods: A cross-sectional, observational study was conducted. Medical records of patients who underwent AGV implantation and had at least 1 year of follow-up were reviewed. HP was defined as an intraocular pressure (IOP) greater than 21 mmHg between the first week and the third postoperative month not attributable to other causes. Success was defined as an IOP between 6 and 21 mmHg, with preservation of light perception and no additional glaucoma surgeries. Statistical analysis was conducted to identify possible risk factors. Results: A total of 193 eyes of 177 patients were included. HP was present in 58%; a higher preoperative IOP and younger age were associated with HP. Pseudophakic or aphakic eyes had a lower HP rate. Failure was present in 29%; neovascular glaucoma, worse basal best corrected visual acuity (BCVA), higher baseline IOP, and postoperative complications were linked to a higher likelihood of failure. No difference in the HP rate between the failure and success groups was found. Conclusion: A higher baseline IOP and younger age are associated with HP development; pseudophakia and aphakia might be protective factors. Factors for AGV failure are a worse BCVA, neovascular glaucoma, postoperative complications, and a higher baseline IOP. At 1 year, a higher number of medications were needed to achieve IOP control in the HP group.


Asunto(s)
Implantes de Drenaje de Glaucoma , Glaucoma Neovascular , Glaucoma , Humanos , Estudios de Seguimiento , Glaucoma Neovascular/cirugía , Prevalencia , Estudios Transversales , Resultado del Tratamiento , Implantación de Prótesis , Glaucoma/epidemiología , Glaucoma/cirugía , Glaucoma/tratamiento farmacológico , Presión Intraocular , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/cirugía , Factores de Riesgo , Estudios Retrospectivos
19.
Lancet Glob Health ; 11 Suppl 1: S8, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36866485

RESUMEN

BACKGROUND: Considering the biological variation across subgroups during periods of growth, the role of non-nutritive sweeteners in weight-related outcomes among children and adolescents is unclear. We did a systematic review and meta-analysis to summarise the evidence on experimental and habitual consumption of non-nutritive sweeteners and prospective changes in BMI in paediatric populations. METHODS: We searched eligible (ie, lasting a minimum of 4 weeks) randomised controlled trials of the effect of non-nutritive sweeteners versus non-caloric or caloric comparators on BMI change and prospective cohort studies reporting multivariable-adjusted coefficients for non-nutritive sweetener intake and BMI in children (aged 2-9 years) and adolescents (aged 10-24 years). We generated pooled estimates using random effects meta-analysis and did secondary stratified analyses to explore heterogeneity by study-level and subgroup characteristics. We further evaluated the quality of the included evidence and classified industry-funded studies, or those whose authors were related to the food industry, as having potential conflicts of interest. FINDINGS: From 2789 results, we included five randomised controlled trials (n=1498 participants; median follow-up 19·0 weeks [IQR 13·0-37·5]); three [60%] with potential conflicts of interest), and eight prospective cohort studies (n=35 340 participants; median follow-up 2·5 years [IQR 1·7-6·3]; two [25%] with potential conflicts of interest). Random allocation to intake of non-nutritive sweeteners (25-2400 mg/day, from food and beverages) suggested less BMI gain (standardised mean difference -0·42 kg/m2 [95% CI -0·79 to -0·06]; I2=89%) compared with intake of sugar from food and beverages. Stratified estimates were significant only in adolescents, participants with obesity at baseline, consumers of a mixture of non-nutritive sweeteners, longer trials, and trials not found to have potential conflicts of interest. No randomised controlled trials tested beverages containing non-nutritive sweeteners versus water. Prospective cohorts reported a non-significant association between consumption of beverages containing non-nutritive sweeteners and BMI gain (0·05 kg/m2 [95% CI -0·02 to 0·12]; I2=67%; per daily serving of 355 mL), which was accentuated for adolescents, boys, and cohorts with longer follow-ups. Removing studies with potential conflicts of interest attenuated the estimates. Evidence was predominantly classified as of low to moderate quality. INTERPRETATION: Intake of non-nutritive sweeteners versus sugar in randomised controlled trials resulted in less BMI gain in adolescents and participants with obesity. Better designed studies should contrast beverages containing non-nutritive sweeteners with water. Long-term prospective analyses with changes in repeated measures might clarify the effect of intake of non-nutritive sweeteners on BMI changes in childhood and adolescence. FUNDING: None.


Asunto(s)
Edulcorantes no Nutritivos , Masculino , Humanos , Adolescente , Niño , Estudios Prospectivos , Índice de Masa Corporal , Obesidad , Azúcares
20.
Biomedicines ; 11(2)2023 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-36830926

RESUMEN

Nanomedicine is an interdisciplinary field where nanostructured objects are applied to treat or diagnose disease. Nanoparticles (NPs) are a special class of materials at nanometric scale that can be prepared from lipids, polymers, or noble metals through bottom-up approaches. Biological synthesis is a reliable, sustainable, and non-toxic bottom-up method that uses phytochemicals, microorganisms, and enzymes to induce the reduction of metal ions into NPs. Silver (Ag) NPs exhibit potent therapeutic properties that can be exploited to overcome the limitations of current treatment modalities for human health issues such as lung cancer (LC). Here, we review the preparation of AgNPs using biological synthesis and their application against LC using in vitro and in vivo models. An overview of the staging, diagnosis, genetic mutations, and treatment of LC, as well as its main subtypes, is presented. A summary of the reaction mechanisms of AgNPs using microbial cell cultures, plant extracts, phytochemicals, and amino acids is included. The use of capping agents in the biosynthesis of AgNPs with anticancer activity is also detailed. The history and biological activities of metal-based nanostructures synthesized with gold, copper, palladium, and platinum are considered. The possible anticancer mechanisms of AgNPs against LC models are covered. Our perspective about the future of AgNPs in LC treatment and nanomedicine is added.

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