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1.
Mol Cell ; 83(17): 3108-3122.e13, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37597513

RESUMEN

General protein folding is mediated by chaperones that utilize ATP hydrolysis to regulate client binding and release. Zinc-finger protein 1 (Zpr1) is an essential ATP-independent chaperone dedicated to the biogenesis of eukaryotic translation elongation factor 1A (eEF1A), a highly abundant GTP-binding protein. How Zpr1-mediated folding is regulated to ensure rapid Zpr1 recycling remains an unanswered question. Here, we use yeast genetics and microscopy analysis, biochemical reconstitution, and structural modeling to reveal that folding of eEF1A by Zpr1 requires GTP hydrolysis. Furthermore, we identify the highly conserved altered inheritance of mitochondria 29 (Aim29) protein as a Zpr1 co-chaperone that recognizes eEF1A in the GTP-bound, pre-hydrolysis conformation. This interaction dampens Zpr1⋅eEF1A GTPase activity and facilitates client exit from the folding cycle. Our work reveals that a bespoke ATP-independent chaperone system has mechanistic similarity to ATPase chaperones but unexpectedly relies on client GTP hydrolysis to regulate the chaperone-client interaction.


Asunto(s)
Proteínas Portadoras , GTP Fosfohidrolasas , Chaperonas Moleculares , Factores de Elongación de Péptidos , Proteínas de Saccharomyces cerevisiae , Humanos , Adenosina Trifosfato , GTP Fosfohidrolasas/genética , Guanosina Trifosfato , Chaperonas Moleculares/genética , Factores de Elongación de Péptidos/metabolismo , Saccharomyces cerevisiae , Proteínas Portadoras/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Pliegue de Proteína
2.
Mol Cell ; 83(2): 252-265.e13, 2023 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-36630955

RESUMEN

The conserved regulon of heat shock factor 1 in budding yeast contains chaperones for general protein folding as well as zinc-finger protein Zpr1, whose essential role in archaea and eukaryotes remains unknown. Here, we show that Zpr1 depletion causes acute proteotoxicity driven by biosynthesis of misfolded eukaryotic translation elongation factor 1A (eEF1A). Prolonged Zpr1 depletion leads to eEF1A insufficiency, thereby inducing the integrated stress response and inhibiting protein synthesis. Strikingly, we show by using two distinct biochemical reconstitution approaches that Zpr1 enables eEF1A to achieve a conformational state resistant to protease digestion. Lastly, we use a ColabFold model of the Zpr1-eEF1A complex to reveal a folding mechanism mediated by the Zpr1's zinc-finger and alpha-helical hairpin structures. Our work uncovers the long-sought-after function of Zpr1 as a bespoke chaperone tailored to the biogenesis of one of the most abundant proteins in the cell.


Asunto(s)
Proteínas Portadoras , Chaperonas Moleculares , Proteínas Portadoras/metabolismo , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Biosíntesis de Proteínas , Zinc/metabolismo , Dedos de Zinc , Factor 1 de Elongación Peptídica/metabolismo
3.
Mol Cell ; 81(21): 4467-4480.e7, 2021 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-34687604

RESUMEN

Viral RNA-dependent RNA polymerases (RdRps) are a target for broad-spectrum antiviral therapeutic agents. Recently, we demonstrated that incorporation of the T-1106 triphosphate, a pyrazine-carboxamide ribonucleotide, into nascent RNA increases pausing and backtracking by the poliovirus RdRp. Here, by monitoring enterovirus A-71 RdRp dynamics during RNA synthesis using magnetic tweezers, we identify the "backtracked" state as an intermediate used by the RdRp for copy-back RNA synthesis and homologous recombination. Cell-based assays and RNA sequencing (RNA-seq) experiments further demonstrate that the pyrazine-carboxamide ribonucleotide stimulates these processes during infection. These results suggest that pyrazine-carboxamide ribonucleotides do not induce lethal mutagenesis or chain termination but function by promoting template switching and formation of defective viral genomes. We conclude that RdRp-catalyzed intra- and intermolecular template switching can be induced by pyrazine-carboxamide ribonucleotides, defining an additional mechanistic class of antiviral ribonucleotides with potential for broad-spectrum activity.


Asunto(s)
Pirazinas/química , Virus ARN/genética , ARN Viral/genética , ARN Polimerasa Dependiente del ARN/genética , Recombinación Genética , Ribonucleótidos/química , Animales , Antivirales , Catálisis , Células Cultivadas , Técnicas Genéticas , Genoma , Genoma Viral , Recombinación Homóloga , Humanos , Cinética , Ratones , Ratones Transgénicos , Simulación de Dinámica Molecular , Mutagénesis , Nucleótidos/genética , Conformación Proteica , ARN/química , ARN Polimerasa Dependiente del ARN/metabolismo , RNA-Seq , Transgenes , Virulencia
4.
Nat Immunol ; 16(6): 609-17, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25915731

RESUMEN

Tumor-associated eosinophilia is frequently observed in cancer. However, despite numerous studies of patients with cancer and mouse models of cancer, it has remained uncertain if eosinophils contribute to tumor immunity or are mere bystander cells. Here we report that activated eosinophils were essential for tumor rejection in the presence of tumor-specific CD8(+) T cells. Tumor-homing eosinophils secreted chemoattractants that guided T cells into the tumor, which resulted in tumor eradication and survival. Activated eosinophils initiated substantial changes in the tumor microenvironment, including macrophage polarization and normalization of the tumor vasculature, which are known to promote tumor rejection. Thus, our study presents a new concept for eosinophils in cancer that may lead to novel therapeutic strategies.


Asunto(s)
Vasos Sanguíneos/inmunología , Linfocitos T CD8-positivos/inmunología , Factores Quimiotácticos/inmunología , Eosinófilos/inmunología , Melanoma/inmunología , Neoplasias Cutáneas/inmunología , Animales , Diferenciación Celular , Movimiento Celular , Citotoxicidad Inmunológica , Melanoma/irrigación sanguínea , Melanoma Experimental , Ratones , Ratones Endogámicos C57BL , Trasplante de Neoplasias , Neovascularización Patológica/inmunología , Neovascularización Fisiológica , Neoplasias Cutáneas/irrigación sanguínea , Carga Tumoral/inmunología , Microambiente Tumoral
5.
Nucleic Acids Res ; 52(4): 2066-2077, 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38180814

RESUMEN

Limiting the spread of synthetic genetic information outside of the intended use is essential for applications where biocontainment is critical. In particular, biocontainment of engineered probiotics and plasmids that are excreted from the mammalian gastrointestinal tract is needed to prevent escape and acquisition of genetic material that could confer a selective advantage to microbial communities. Here, we built a simple and lightweight biocontainment system that post-translationally activates a site-specific DNA endonuclease to degrade DNA at 18°C and not at higher temperatures. We constructed an orthogonal set of temperature-sensitive meganucleases (TSMs) by inserting the yeast VMA1 L212P temperature-sensitive intein into the coding regions of LAGLIDADG homing endonucleases. We showed that the TSMs eliminated plasmids carrying the cognate TSM target site from laboratory strains of Escherichia coli at the permissive 18°C but not at higher restrictive temperatures. Plasmid elimination is dependent on both TSM endonuclease activity and intein splicing. TSMs eliminated plasmids from E. coli Nissle 1917 after passage through the mouse gut when fecal resuspensions were incubated at 18°C but not at 37°C. Collectively, our data demonstrates the potential of thermoregulated meganucleases as a means of restricting engineered plasmids and probiotics to the mammalian gut.


Asunto(s)
Inteínas , Proteínas de Saccharomyces cerevisiae , Animales , Ratones , Inteínas/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Empalme de Proteína , ADN/metabolismo , Saccharomyces cerevisiae/genética , Plásmidos/genética , Mamíferos/genética , ATPasas de Translocación de Protón , Proteínas de Saccharomyces cerevisiae/genética
6.
Nucleic Acids Res ; 51(1): 315-336, 2023 01 11.
Artículo en Inglés | MEDLINE | ID: mdl-36546762

RESUMEN

Some of the most efficacious antiviral therapeutics are ribonucleos(t)ide analogs. The presence of a 3'-to-5' proofreading exoribonuclease (ExoN) in coronaviruses diminishes the potency of many ribonucleotide analogs. The ability to interfere with ExoN activity will create new possibilities for control of SARS-CoV-2 infection. ExoN is formed by a 1:1 complex of nsp14 and nsp10 proteins. We have purified and characterized ExoN using a robust, quantitative system that reveals determinants of specificity and efficiency of hydrolysis. Double-stranded RNA is preferred over single-stranded RNA. Nucleotide excision is distributive, with only one or two nucleotides hydrolyzed in a single binding event. The composition of the terminal basepair modulates excision. A stalled SARS-CoV-2 replicase in complex with either correctly or incorrectly terminated products prevents excision, suggesting that a mispaired end is insufficient to displace the replicase. Finally, we have discovered several modifications to the 3'-RNA terminus that interfere with or block ExoN-catalyzed excision. While a 3'-OH facilitates hydrolysis of a nucleotide with a normal ribose configuration, this substituent is not required for a nucleotide with a planar ribose configuration such as that present in the antiviral nucleotide produced by viperin. Design of ExoN-resistant, antiviral ribonucleotides should be feasible.


Asunto(s)
Antivirales , Tratamiento Farmacológico de COVID-19 , Ribonucleótidos , Humanos , Antivirales/farmacología , Exorribonucleasas/metabolismo , Ribonucleótidos/química , ARN Viral/genética , ARN Viral/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Proteínas no Estructurales Virales/metabolismo , Replicación Viral/genética , Diseño de Fármacos
7.
J Infect Dis ; 2024 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-38801652

RESUMEN

Ebola virus (EBOV) infection results in Ebola virus disease (EVD), an often severe disease with a nonspecific presentation. Since its recognition, periodic outbreaks of EVD continue to occur in sub-Saharan Africa. The 2013-2016 West African EVD outbreak was the largest recorded, resulting in a substantial cohort of EVD survivors with persistent health complaints and variable immune responses. In this study, we characterize humoral immune responses in EVD survivors and their contacts in Eastern Sierra Leone. We found high levels of EBOV IgG in EVD survivors and lower yet substantial antibody levels in household contacts, suggesting subclinical transmission. Neutralizing antibody function was prevalent but variable in EVD survivors, raising questions about the durability of immune responses from natural infection with EBOV. Additionally, we found that certain discrete symptoms-ophthalmologic and auditory-are associated with EBOV IgG seropositivity, while an array of symptoms are associated with the presence of neutralizing antibody.

8.
J Hum Genet ; 2024 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-39085459

RESUMEN

VLDLR cerebellar hypoplasia is characterized by intellectual disability, non-progressive cerebellar ataxia, and seizures. The characteristic MRI findings include hypoplasia of the inferior portion of the cerebellar vermis and hemispheres, simplified cortical gyration, and a small brain stem. Biallelic VLDLR pathogenic variants cause loss-of-function of the encoded very low-density lipoprotein receptor. VLDLR exons 4 and 16 are alternatively spliced, resulting in the expression of four transcript variants, including two exon 4-lacking mRNAs expressed in the human brain. Previously reported VLDLR pathogenic variants affect all four transcript variants. Here we report on two sisters with facial dysmorphism, microcephaly, intellectual disability, and normal brain imaging. Exome sequencing in one patient identified the homozygous VLDLR nonsense variant c.376C>T; p.(Gln126*) in exon 4; her similarly affected sister also carried the homozygous variant and parents were heterozygous carriers. VLDLR transcript analysis identified mRNAs with and without exon 4 in patient fibroblasts, while exon 4-containing VLDLR mRNAs were predominantly detected in control fibroblasts. We found significantly reduced VLDLR mRNA levels in patient compared to control cells, likely caused by nonsense-mediated mRNA decay of exon 4-containing VLDLR transcripts. Expression of neuronal VLDLR isoforms produced from exon 4-lacking transcripts may have protected both patients from developing the cerebellar hypoplasia phenotype.

9.
Nitric Oxide ; 144: 47-57, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38307377

RESUMEN

Heart failure (HF) is a multifactorial, heterogeneous systemic disease that is considered one of the leading causes of death and morbidity worldwide. It is well-known that endothelial dysfunction (ED) plays an important role in cardiac disease etiology. A reduction in the bioavailability of nitric oxide (NO) in the bloodstream leads to vasoconstriction and ED. Many studies indicated diminishment of peripheral arteries vasodilation that is mediated by the endothelium in the of patients with chronic HF. With the advancement of nanomedicine, nanotechnology can provide adequate solutions for delivering exogenous NO with the aid of nanoparticles (NPs) to treat ED. The properties of superparamagnetic iron oxide nanoparticles (SPIONs) enable both passive and active delivery of drugs. This prompted us to investigate the efficacy of our newly-developed hydrogel nanoparticles (NO-RPs) for the delivery and sustained release of NO gas to alleviate cardiac failure and inflammation in the heart failure zebrafish model. The hydrogel NO-RPs incorporate SPIONS and NO precursor. The sustainend release of NO in the NO-RPs (4200 s), overcomes the problem of the short half life of NO in vivo which is expected to ameliorate the reduced NO bioavailabilty, and its consequences in endothelial and cardiac dysfunction. Zebrafish embryos were used as the animal model in this study to determine the effect of SPIONs-loaded NO-RPs on the cardiovascular system. Cardiac failure was induced in 24hpf embryos by exposure to aristolochic acid (AA)(0.25, 0.5 µM) for 8 h, followed by the SPIONs-loaded NO-RPs (0.25, 0.5 mg/ml) for 48 h, experimental groups included: control group which is healthy non treated zebrafish embryos, AA injured zebrafish embryos (HF) model,and NO-RP treated HF zebrafish embryos. Survival rate was assessed at 72hpf. Cardiac function was also evaluated by analyzing cardiac parameters including heartbeat, major blood vessels primordial cardinal vein and dorsal aorta (PCV &DA) diameter, blood flow velocity in PCV & DA vessels, cardiac output, and PCV & DA shear stresses. All cardiac parameters were analyzed with the aid of MicroZebraLab blood flow analysis software from Viewpoint. In addition, we studied the molecular effects of the developed NO-RPs on the mRNA expression of selected pro-inflammatory markers: IL-6, and Cox-2. Our findings demonstrated that the NO-RPs improved the survival rate in the heart failure zebrafish model and reversed heart failure by enhancing blood flow perfusion in Zebrafish embryos, significantly. In addition, RT-PCR results showed that the NO-RPs significantly reduced the expression of pro-inflammatory markers (lL-6&COX-2) in the heart failure zebrafish model. Our study confirmed that the developed SPIONs-loaded NO-RPs are effective tool to alleviate cardiac failure and inflammation in the HF zebrafish model.


Asunto(s)
Estructuras Embrionarias , Insuficiencia Cardíaca , Nanopartículas , Sistema Porta/embriología , Humanos , Animales , Pez Cebra , Óxido Nítrico/uso terapéutico , Ciclooxigenasa 2 , Insuficiencia Cardíaca/tratamiento farmacológico , Insuficiencia Cardíaca/metabolismo , Inflamación/inducido químicamente , Hidrogeles/efectos adversos
10.
Malar J ; 23(1): 144, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38741101

RESUMEN

BACKGROUND: Monitoring therapeutic efficacy is important to ensure the efficacy of artemisinin-based combination therapy (ACT) for malaria. The current first-line treatment for uncomplicated malaria recommended by the National Malaria Control Program in Niger is artemether-lumefantrine (AL). In 2020, an in vivo study was carried out to evaluate clinical and parasitological responses to AL as well as the molecular resistance to the drug in three sentinel sites: Agadez, Tessaoua and Gaya, in Niger. METHODS: A multi-center, single-arm trial was conducted according to the 28-day World Health Organization (WHO) 2009 therapeutic efficacy study protocol. Children between 6 months and 15 years with confirmed uncomplicated Plasmodium falciparum infection and 1000-200,000 asexual parasites/µL of blood were enrolled and followed up for 28 days. Uncorrected and PCR-corrected efficacy results at day 28 were calculated, and molecular correction was performed by genotyping the msp1, msp2, and glurp genes. The pfk13, pfdhfr, pfdhps, pfcrt and pfmdr genes were analyzed by PCR and Sanger sequencing. The Kaplan-Meier curve assessed parasite clearance. RESULTS: A total of 255 patients were enrolled in the study. The adequate clinical and parasitological response after PCR correction was 98.9% (95% CI 96.4-101.0%), 92.2% (85.0-98.5%) and 97.1% (93.1-101.0%) in Gaya, Tessaoua and Agadez, respectively. No adverse events were observed. Ten mutations (SNP) were found, including 7 synonyms (K248K, G690G, E691E, E612E, C469C, G496G, P718P) and 3 non-synonyms (N594K, R255K, V714S). Two mutations emerged: N594K and V714S. The R255K mutation detected in Southeast Asia was also detected. The pfdhpsK540E and pfdhfrI164L mutations associated with high levels of resistance are absent. There is a reversal of chloroquine resistance. CONCLUSION: The study findings indicate that AL is effective and well tolerated for the treatment of uncomplicated malaria in three sites in Niger. The emergence of a pfk13 mutation requires additional testing such as the Ring Stage Assay and CRISPR/Cas9 to confirm the role of these emerging mutations. Trial registration NCT05070520, October 7, 2021.


Asunto(s)
Antimaláricos , Combinación Arteméter y Lumefantrina , Malaria Falciparum , Plasmodium falciparum , Combinación Arteméter y Lumefantrina/uso terapéutico , Malaria Falciparum/tratamiento farmacológico , Antimaláricos/uso terapéutico , Antimaláricos/efectos adversos , Preescolar , Humanos , Niger , Niño , Lactante , Adolescente , Masculino , Femenino , Plasmodium falciparum/efectos de los fármacos , Plasmodium falciparum/genética , Resistencia a Medicamentos/genética
11.
J Cardiovasc Magn Reson ; 26(2): 101061, 2024 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-39002898

RESUMEN

BACKGROUND: Clinical guidelines and scientific data increasingly support the appropriate use of cardiovascular magnetic resonance (CMR) . The extent of CMR adoption across the United States (US) remains unclear. This observational analysis aims to capture CMR practice patterns in the US. METHODS: Commissioned reports from the Society for Cardiovascular Magnetic Resonance (SCMR), pre-existing survey data from CMR centers, and socioeconomic and coronary heart disease data from the Centers for Disease Control and Prevention were used. The location of imaging centers performing CMR was based on 2018 Medicare claims. Secondary analysis was performed on center-specific survey data from 2017-2019, which were collected by members of the SCMR US Advocacy Subcommittee for quality improvement purposes. The correlation between the number of imaging centers billing for CMR services per million persons, socioeconomic determinants, and coronary heart disease epidemiology was determined. RESULTS: A total of 591 imaging centers billed the Center for Medicare & Medicaid Services for CMR services in 2018 and 112 (of 155) unique CMR centers responded to the survey. In 2018, CMR services were available in almost all 50 states. Minnesota was the state with the highest number of CMR centers per million Medicare beneficiaries (52.6 centers per million), and Maine had the lowest (4.4 per million). The total density of CMR centers was 16 per million for US Medicare beneficiaries. Sixty-eight percent (83 of 112) of survey responders were cardiologists, and 28% (31/112) were radiologists. In 72% (71/112) of centers, academic health care systems performed 81%-100% of CMR exams. The number of high-volume centers (>500 scans per year) increased by seven between 2017 and 2019. In 2019, 53% (59/112) of centers were considered high-volume centers and had an average of 19 years of experience. Centers performing <50 scans had on average 3.5 years of experience. Approximate patient wait time for a CMR exam was 2 weeks to 1 month. CONCLUSION: Despite increasing volume and availability in almost all 50 states, CMR access remains geographically variable. Advocacy efforts to improve access and innovations that reduce imaging time and exam complexity have the potential to increase the adoption of CMR technology.

12.
Virus Genes ; 60(1): 1-8, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37906378

RESUMEN

The extensive mass gathering of pilgrims from all over the world, as well as the constant flow of foreign workers via country entry crossings, raises the likelihood of respiratory virus outbreaks spreading and evolving in Saudi Arabia. Here, we report the sequence and phylogenetic analysis of the human parainfluenza type-2 (HPIV-2) in nasopharyngeal aspirates (NPAs) collected from Riyadh, Saudi Arabia, from 2020/21 to 2021/22 seasons. RNA was extracted from the clinical samples and subjected to RT-PCR analysis for the detection of IAV and IBV. The full-length HN gene of HPIV-2 was amplified and sequenced. Multiple sequence alignments (both nucleotides and deduced amino acids) were aligned using Clustal W, MegAlign program of Lasergene software, and MEGA 7.0. HPIV-2 was found in (4; 2% of 200) NPAs. Sequence and phylogenetic analysis results showed that indicated a genotype shifting from G3 to G4a with 83% sequence homology 62-M786 from Japan, which was prominent throughout the winter seasons of 2008/09. Multiple amino acid sequence alignment revealed 25 sites of possible difference between G3 genotypes and G4a. A total of twenty- two of these locations were shared by the other G4a genotypes, whereas three positions, 67 V, 175 S, and 377Q, were exclusively shared by G3. Only eight conserved N-glycosylation sites were found at amino acids 6(NLS), 286(NTT), 335(NIT), 388(NNS), 498(NES), 504(NPT), 517(NTT), and 539(NGT) in four Riyadh isolates. Our findings also revealed that the G4a genotype of HPIV-2 predominated in our samples population during the winter seasons of 2020/21 and 2021/22. Further research with a larger sample size covering numerous regions of Saudi Arabia throughout different epidemic seasons is needed to achieve an improved knowledge of HPIV-2 circulation.


Asunto(s)
Infecciones por Paramyxoviridae , Humanos , Arabia Saudita/epidemiología , Filogenia , Secuencia de Aminoácidos , Aminoácidos/genética , Virus de la Parainfluenza 1 Humana , Virus de la Parainfluenza 3 Humana/genética , Virus de la Parainfluenza 2 Humana
13.
Nature ; 556(7701): 376-380, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29643507

RESUMEN

Ribosome-associated mRNA quality control mechanisms ensure the fidelity of protein translation1,2. Although these mechanisms have been extensively studied in yeast, little is known about their role in mammalian tissues, despite emerging evidence that stem cell fate is controlled by translational mechanisms3,4. One evolutionarily conserved component of the quality control machinery, Dom34 (in higher eukaryotes known as Pelota (Pelo)), rescues stalled ribosomes 5 . Here we show that Pelo is required for mammalian epidermal homeostasis. Conditional deletion of Pelo in mouse epidermal stem cells that express Lrig1 results in hyperproliferation and abnormal differentiation of these cells. By contrast, deletion of Pelo in Lgr5-expressing stem cells has no effect and deletion in Lgr6-expressing stem cells induces only a mild phenotype. Loss of Pelo results in accumulation of short ribosome footprints and global upregulation of translation, rather than affecting the expression of specific genes. Translational inhibition by rapamycin-mediated downregulation of mTOR (mechanistic target of rapamycin kinase) rescues the epidermal phenotype. Our study reveals that the ribosome-rescue machinery is important for mammalian tissue homeostasis and that it has specific effects on different stem cell populations.


Asunto(s)
Evolución Biológica , Epidermis/metabolismo , Homeostasis , Ribosomas/metabolismo , Células Madre/metabolismo , Animales , Proteínas de Ciclo Celular/deficiencia , Proteínas de Ciclo Celular/genética , Diferenciación Celular , Proliferación Celular , Progresión de la Enfermedad , Endonucleasas , Células Epidérmicas , Epidermis/patología , Femenino , Homeostasis/genética , Masculino , Glicoproteínas de Membrana/metabolismo , Ratones , Proteínas de Microfilamentos/deficiencia , Proteínas de Microfilamentos/genética , Mutación , Proteínas del Tejido Nervioso/metabolismo , Fenotipo , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Células Madre/citología , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Serina-Treonina Quinasas TOR/metabolismo
14.
BMC Vet Res ; 20(1): 156, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664683

RESUMEN

The present study aimed to determine the major cause of the high mortality affecting farmed gilthead seabream (Sparus aurata) and controlling this disease condition. Fifteen diseased S. aurata were sampled from a private fish farm located at Eldeba Triangle, Damietta, fish showed external skin hemorrhages, and ulceration. Bacterial isolates retrieved from the diseased fish were identified biochemically as Pseudomonas putida and then confirmed by phylogenetic analysis of the 16 S rRNA gene sequence. P. putida was also isolated from three batches of tilapia-trash feed given to S. aurata. Biofilm and hemolytic assay indicated that all P. putida isolates produced biofilm, but 61.11% can haemolyse red blood cells. Based on the antibiotic susceptibility test results, P. putida was sensitive to florfenicol with minimum inhibitory concentrations ranging between 0.25 and 1.0 µg mL- 1, but all isolates were resistant to ampicillin and sulfamethoxazole-trimethoprim. Pathogenicity test revealed that P. putida isolate (recovered from the tilapia-trash feed) was virulent for S. aurata with LD50 equal to 4.67 × 107 colony forming unit (CFU) fish- 1. After intraperitoneal (IP) challenge, fish treated with 10 mg kg- 1 of florfenicol showed 16.7% mortality, while no mortality was recorded for the fish group that received 20 mg kg- 1. The non-treated fish group showed 46.7% mortality after bacterial challenge. HPLC analysis of serum florfenicol levels reached 1.07 and 2.52 µg mL- 1 at the 5th -day post-drug administration in the fish groups received 10 and 20 mg kg- 1, respectively. In conclusion, P. putida was responsible for the high mortality affecting cultured S. aurata, in-feed administration of florfenicol (20 mg kg- 1) effectively protected the challenged fish.


Asunto(s)
Alimentación Animal , Antibacterianos , Enfermedades de los Peces , Pseudomonas putida , Dorada , Tianfenicol , Tianfenicol/análogos & derivados , Animales , Tianfenicol/uso terapéutico , Tianfenicol/farmacología , Tianfenicol/administración & dosificación , Enfermedades de los Peces/microbiología , Enfermedades de los Peces/tratamiento farmacológico , Pseudomonas putida/efectos de los fármacos , Antibacterianos/uso terapéutico , Antibacterianos/farmacología , Antibacterianos/administración & dosificación , Alimentación Animal/análisis , Dorada/microbiología , Infecciones por Pseudomonas/veterinaria , Infecciones por Pseudomonas/tratamiento farmacológico , Infecciones por Pseudomonas/microbiología , Pruebas de Sensibilidad Microbiana/veterinaria , Tilapia , Filogenia , ARN Ribosómico 16S/genética , Biopelículas/efectos de los fármacos
15.
BMC Vet Res ; 20(1): 269, 2024 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-38907235

RESUMEN

This study was conducted to evaluate the effects of thyme, ginger, and their nano-particles, as alternatives to antibiotic growth promotors (AGP), on productive performance, carcass traits, meat quality and gut health of broiler chickens. A total of 270 one-day-old broiler chicks were randomly distributed into 6 groups, each consisting of 3 replicates (n = 15 chicks/replicate). The birds in group 1 were fed the control diet which contained neither antibiotic growth promotors nor phytogenic feed additives (PFA). Birds in group 2 were fed diets containing 0.05% of AGP (Bacitracin methylene disalicylate). Chicks in group 3 and 4 were fed diets supplemented with 1.0% of thyme and ginger, respectively, whereas birds in group 5 and 6 were offered diets including 0.10% of nano-thyme and nano-ginger, respectively. The experiment lasted for 35 days. It was found that thyme and ginger with their nano-products, like the antibiotic, improved the body weight, weight gain and feed conversion rate of birds. The effect of ginger and nano-ginger on body weight and weight gain was greater than other treatments. During the overall feeding period, the feed cost of production was the highest in antibiotic group, but was the lowest in ginger and nano-ginger treatments. There was no effect of dietary treatments on carcass yield or organs weight except bursa of Fabricius and abdominal fat. Thyme, ginger and their nano-composites increased the weight of bursa and reduced the abdominal fat amount. The phytogenic additives and their nano-particles improved the colour, water holding capacity, and flavor of meat. Moreover, these additives reduced the total intestinal bacterial count as well as the total aerobic mesophilic count of meat. The effect of PFA and their nano-particles on the bacterial count was similar to that of antibiotic. In conclusion, thyme and ginger with their nano- particles can be considered as promising agents in feeding of broilers to improve the growth performance, gut health and meat quality. Moreover, these additives can be used as alternatives to AGP to overcome its health hazards and the high cost. The nanotechnology of herbal plants enables them to be added in smaller amounts in poultry diets with producing the same effect of raw ingredients, and this could be due to the higher bioavailability.


Asunto(s)
Alimentación Animal , Pollos , Dieta , Carne , Nanopartículas , Thymus (Planta) , Zingiber officinale , Animales , Pollos/crecimiento & desarrollo , Pollos/microbiología , Zingiber officinale/química , Thymus (Planta)/química , Alimentación Animal/análisis , Dieta/veterinaria , Carne/normas , Nanopartículas/administración & dosificación , Suplementos Dietéticos , Microbioma Gastrointestinal/efectos de los fármacos , Masculino
16.
BMC Vet Res ; 20(1): 250, 2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38849855

RESUMEN

BACKGROUND: Buffalo spermatozoa have a distinct membrane structure that makes them more vulnerable to cryopreservation, resulting in lower-quality post-thawed sperm. This decreases the success rate of artificial insemination in buffaloes. Understanding and addressing these specific vulnerabilities are essential for improving reproductive techniques in buffalo populations. The properties of cryopreserved buffalo bull semen were examined in this study regarding the impact of adding autologous platelet-rich plasma (PRP) to OptiXcell® or Tris egg yolk-based extenders. Ten buffalo bulls were used to collect semen. Each bull's ejaculate was separated into two main equal amounts, each of which was then diluted with either OptiXcell® or Tris egg yolk-based extender, supplemented with various PRP concentrations (5%, 10%, and 15%), and the control (0%), before being cryopreserved according to established protocols. Following equilibration and thawing, the quality and functionality of the sperm were evaluated, along with the antioxidant enzyme activities (GSH and TAC), malondialdehyde (MDA) content, and in vivo fertilization rate of the thawed semen. RESULTS: All PRP concentrations in both extenders, particularly 10% PRP, improved the quality and functionality of the sperm in both equilibrated and frozen-thawed semen. Additionally, the antioxidant enzyme activities in both extenders were higher in the PRP-supplemented groups compared to the control group in thawed semen (P < 0.05). All post-thaw sperm quality, antioxidant enzyme activities, and functionality aside from DNA integrity were higher (P < 0.05) in the PRP-supplemented OptiXcell® than in the PRP-supplemented Tris egg yolk-based extender. The fertility of cryopreserved semen in the extenders supplemented with 10% and 15% PRP increased (P < 0.05) significantly more than that of the control extenders, with 10% PRP being the optimum concentration in OptiXcell® (80%) compared to that of Tris egg yolk-based extender (66.67%) and control of two extenders (53.33% and 46.67%, respectively). CONCLUSIONS: Even though autologous PRP-supplemented extenders have a protective impact on equilibrated and cryopreserved semen, 10% PRP-supplemented OptiXcell® extenders are more effective at preserving post-thaw semen quality, functionality, and antioxidant capacity, which increases the in vivo fertility of buffalo bulls.


Asunto(s)
Búfalos , Criopreservación , Plasma Rico en Plaquetas , Preservación de Semen , Animales , Masculino , Criopreservación/veterinaria , Criopreservación/métodos , Preservación de Semen/veterinaria , Preservación de Semen/métodos , Fertilidad , Yema de Huevo/química , Análisis de Semen/veterinaria , Crioprotectores/farmacología , Inseminación Artificial/veterinaria , Femenino , Semen , Espermatozoides/fisiología , Espermatozoides/efectos de los fármacos
17.
Cell Biochem Funct ; 42(5): e4093, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38978319

RESUMEN

The main objective of the study is to evaluate the antioxidant, anticancer, and antimicrobial activities of Anchusa officinalis L. in vitro and in silico. The dried aerial parts of A. officinalis L. were extracted with methanol. Total phenolic and flavonoid content was analyzed. Antioxidant and antimicrobial effects were tested against both gram-positive and gram-negative bacteria. Gas chromatography-mass spectrometry analysis revealed the presence of 10 phytochemical compounds, and cyclobutane (26.07%) was identified as the major photochemical compound. The methanol extract exhibited the maximum amount of total phenolic content (118.24 ± 4.42 mg QE/g dry weight of the dry extract) (R2 = 0.994) and the total flavonoid content was 94 ± 2.34 mg QE/g dry weight of the dry extract (R2 = 0.999). The IC50 value for 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid was 107.12 ± 3.42 µg/mL, and it was high for 1,1-diphenyl-2-picryl hydrazyl (123.94 ± 2.31 µg/mL). The IC50 value was 72.49 ± 3.14 against HepG2 cell lines, and a decreased value was obtained (102.54 ± 4.17 g/mL) against MCF-7 cell lines. The methanol extract increased the expression of caspase mRNA and Bax mRNA levels when compared to the control experiment (p < .05). The conclusions, A. officinalis L. aerial parts extract exhibited antibacterial, antifungal, and antioxidant activities.


Asunto(s)
Antioxidantes , Metanol , Componentes Aéreos de las Plantas , Extractos Vegetales , Extractos Vegetales/farmacología , Extractos Vegetales/química , Humanos , Componentes Aéreos de las Plantas/química , Antioxidantes/farmacología , Antioxidantes/química , Antioxidantes/aislamiento & purificación , Metanol/química , Pruebas de Sensibilidad Microbiana , Antibacterianos/farmacología , Antibacterianos/química , Antibacterianos/aislamiento & purificación , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Antineoplásicos Fitogénicos/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Antiinfecciosos/farmacología , Antiinfecciosos/química , Células MCF-7 , Simulación por Computador , Flavonoides/farmacología , Flavonoides/química , Fenoles/farmacología , Fenoles/química , Apoptosis/efectos de los fármacos
18.
BMC Med Imaging ; 24(1): 205, 2024 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-39112928

RESUMEN

In order to increase the likelihood of obtaining treatment and achieving a complete recovery, early illness identification and diagnosis are crucial. Artificial intelligence is helpful with this process by allowing us to rapidly start the necessary protocol for treatment in the early stages of disease development. Artificial intelligence is a major contributor to the improvement of medical treatment for patients. In order to prevent and foresee this problem on the individual, family, and generational levels, Monitoring the patient's therapy and recovery is crucial. This study's objective is to outline a non-invasive method for using mammograms to detect breast abnormalities, classify breast disorders, and identify cancerous or benign tumor tissue in the breast. We used classification models on a dataset that has been pre-processed so that the number of samples is balanced, unlike previous work on the same dataset. Identifying cancerous or benign breast tissue requires the use of supervised learning techniques and algorithms, such as random forest (RF) and decision tree (DT) classifiers, to examine up to thirty features, such as breast size, mass, diameter, circumference, and the nature of the tumor (solid or cystic). To ascertain if the tissue is malignant or benign, the examination's findings are employed. These features are mostly what determines how effectively anything may be categorized. The DT classifier was able to get a score of 95.32%, while the RF satisfied a far higher 98.83 percent.


Asunto(s)
Neoplasias de la Mama , Mamografía , Humanos , Neoplasias de la Mama/diagnóstico por imagen , Femenino , Mamografía/métodos , Algoritmos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Sensibilidad y Especificidad , Árboles de Decisión , Persona de Mediana Edad
19.
Orthod Craniofac Res ; 27(4): 598-605, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38426595

RESUMEN

OBJECTIVE: This prospective clinical study aimed to evaluate the immediate impact of Twin-block appliance insertion on the sleep of adolescents using a wearable device. MATERIALS AND METHODS: A total of 24 girls, aged 11-13 years, with Class II division 1 molar relationship, skeletal class 2 malocclusion (ANB ≥5) and overjet measuring ≥5 mm were selected. Exclusion criteria included a history of previous orthodontic treatment, systemic disease, irregular sleep pattern, obstructive sleep apnea, medical history of breathing disorders, or concurrent use of medications. Participants wore a wearable device to measure sleep parameters, including deep sleep, light sleep, minutes awake during sleep, wake-up times, bedtimes and total sleep times. The participants wore the device for 10 days prior to Twin-block insertion and sleep data were collected for another 10 days after insertion. RESULTS: Following the insertion of the Twin-block appliance, there was a highly statistically significant shift in bedtime and wake-up time to later hours (P < .001). All participants experienced a highly significant delay in bedtime compared to the recommended 10 pm time (P < .001). Additionally, there was a significant increase in the duration of light sleep (P < .05). However, the effect on deep sleep, minutes awake during sleep and sleep duration was not statistically significant. None of the sleep parameters tested showed statistically significant changes between the first 5 days after Twin-block insertion with the subsequent 5 days. CONCLUSION: The immediate insertion of the Twin-block appliance disrupts sleep onset, wake-up time and light sleep during the specified period of 10 days.


Asunto(s)
Maloclusión Clase II de Angle , Sueño , Dispositivos Electrónicos Vestibles , Humanos , Femenino , Adolescente , Niño , Estudios Prospectivos , Maloclusión Clase II de Angle/terapia , Sueño/fisiología , Diseño de Aparato Ortodóncico , Factores de Tiempo
20.
J Assist Reprod Genet ; 41(3): 751-756, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38277113

RESUMEN

PURPOSE: To investigate the genetic etiology of patients with female infertility. METHODS: Whole Exome Sequencing was performed on genomic DNA extracted from the patient's blood. Exome data were filtered for damaging rare biallelic variants in genes with possible roles in reproduction. Sanger sequencing was used to validate the selected variants and segregate them in family members. RESULTS: A novel homozygous likely pathogenic variant, c.626G>A, p.Trp209*, was identified in the TERB1 gene of the patient. Additionally, we report a second homozygous pathogenic TERB1 variant, c.1703C>G, p.Ser568*, in an infertile woman whose azoospermic brother was previously described to be homozygous for her variant. CONCLUSIONS: Here, we report for the first time two homozygous likely pathogenic and pathogenic TERB1 variants, c.626G>A, p.Trp209* and c.1703C>G, p.Ser568*, respectively, in two unrelated women with primary infertility. TERB1 is known to play an essential role in homologous chromosome movement, synapsis, and recombination during the meiotic prophase I and has an established role in male infertility in humans. Our data add TERB1 to the shortlist of Meiosis I genes associated with human infertility in both sexes.


Asunto(s)
Azoospermia , Proteínas de Ciclo Celular , Proteínas de Unión al ADN , Infertilidad Masculina , Femenino , Humanos , Azoospermia/genética , Proteínas de Ciclo Celular/genética , Homocigoto , Infertilidad Masculina/genética , Meiosis , Proteínas de Unión al ADN/genética
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