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This study investigated the sero-epidemiology of bluetongue in ruminants in North-Western Pakistan. A total of 3,173 serum samples were collected from small (n = 1,651) and large (n = 1,522) ruminants being reared by farmers in 14 districts. Antibodies to bluetongue virus (BTV) were detected using competitive ELISA. The overall prevalence of BTV antibodies was 65%. A significant association (P < 0.05) between the prevalence of BTV antibodies and the risk factors including sex, species, age, area, husbandry practices and breed was shown by univariate analysis. In multivariate analysis, the seroprevalence was 6.5 (95% CL = 3.7-11.4), 5.9 (95% CL = 3.8-9.4) and 2.4 (95% CL = 1.5-3.7) times higher in buffaloes, cattle and goats than sheep, respectively. The seroprevalence was 1.4 (95% CL = 1.1-1.7) times higher in local breeds than in cross/exotic breeds. The seroprevalence was 1.6 (95% CL = 1.1 to 2.3) times higher in sedentary animals than in nomadic animals. The seroprevalence was significantly associated with age. Further work is required to determine the BTV serotypes prevalent in the study area for effective control of the disease.
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Virus de la Lengua Azul , Lengua Azul , Enfermedades de las Cabras , Animales , Pakistán/epidemiología , Estudios Seroepidemiológicos , Lengua Azul/epidemiología , Lengua Azul/virología , Virus de la Lengua Azul/inmunología , Femenino , Masculino , Enfermedades de las Cabras/epidemiología , Enfermedades de las Cabras/virología , Ovinos , Cabras , Bovinos , Anticuerpos Antivirales/sangre , Rumiantes/virología , Factores de Riesgo , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/virología , Crianza de Animales Domésticos , Enfermedades de las Ovejas/epidemiología , Enfermedades de las Ovejas/virología , PrevalenciaRESUMEN
Pancreatic cancer (PC) is assumed to be an intimidating and deadly malignancy due to being the leading cause of cancer-led mortality, predominantly affecting males of older age. The overall (5 years) survival rate of PC is less than 9% and is anticipated to be aggravated in the future due to the lack of molecular acquaintance and diagnostic tools for its early detection. Multiple factors are involved in the course of PC development, including genetics, cigarette smoking, alcohol, family history, and aberrant epigenetic signatures of the epigenome. In this review, we will mainly focus on the genetic mutations and epigenetic signature of PC. Multiple tumor suppressor and oncogene mutations are involved in PC initiation, including K-RAS, p53, CDKN2A, and SMAD4. The mutational frequency of these genes ranges from 50 to 98% in PC. The nature of mutation diagnosis is mostly homozygous deletion, point mutation, and aberrant methylation. In addition to genetic modification, epigenetic alterations particularly aberrant hypermethylation and hypomethylation also predispose patients to PC. Hypermethylation is mostly involved in the downregulation of tumor suppressor genes and leads to PC, while multiple genes also represent a hypomethylation status in PC. Several renewable drugs and detection tools have been developed to cope with this aggressive malady, but all are futile, and surgical resection remains the only choice for prolonged survival if diagnosed before metastasis. However, the available therapeutic development is insufficient to cure PC. Therefore, novel approaches are a prerequisite to elucidating the genetic and epigenetic mechanisms underlying PC progression for healthier lifelong survival.
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Epigénesis Genética , Mutación , Neoplasias Pancreáticas , Homocigoto , Humanos , Neoplasias Pancreáticas/genética , Eliminación de SecuenciaRESUMEN
Diarrhea is the leading cause of childhood morbidity and mortality particularly in developing countries and rotavirus has been identified as the major pathogen associated with diarrheal infections. This study was conducted to detect genotypic distribution of predominant rotavirus strains circulating in children suffering from acute gastroenteritis in Rawalpindi, Pakistan. Stool specimens were collected from children ≤5 years of age, visiting Military Hospital, Rawalpindi, with signs and symptoms of acute gastroenteritis. Two hundred and eighty-four specimens were collected during the period from April 2017 to March 2018. Enzyme immunoassay was performed for detection of rotavirus and reverse transcription-PCR (RT-PCR) was carried out for amplification of VP7 and VP4 gene segments followed by multiplex PCR using genotype-specific primers. Out of 284 children, 71 were found rotavirus positive and among them, 54% were females and 46% males. Our findings showed 92% of infection among children ≤2 years of age, while, the peak age of rotavirus incidence was found to be 6-12 months. Although, rotavirus infection was observed throughout the year but frequency increased in winter. Subtype G1P[8] was more prevalent followed by G2P[4], G3P[8], and G4P[6] subtypes. The results of this study provide insight into the disease burden as well as information on rotavirus diversity which will be useful to develop future strategies to control and prevent diarrheal infections among children.
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Gastroenteritis , Infecciones por Rotavirus , Rotavirus , Antígenos Virales/genética , Niño , Diarrea/epidemiología , Heces , Femenino , Gastroenteritis/epidemiología , Genotipo , Humanos , Lactante , Masculino , Pakistán/epidemiología , Rotavirus/genética , Infecciones por Rotavirus/epidemiologíaRESUMEN
Antimicrobial resistance is a growing concern of global public health. The emergence of colistin-resistance among carbapenem-resistant (CPR) Gram-negative bacteria causing fear of pan-resistance, treatment failure, and high mortality across the globe. AIM: To determine the genotypic colistin-resistance mechanisms among colistin-resistant (CR)Gram-negative clinical isolates along with genomic insight into hypermucoviscous(hv)-CR-Klebsiella pneumoniae. METHODS: Phenotypic colistin-resistance via broth-microdilution method. PCR-based detection of plasmid-mediated colistin resistance genes(mcr-1,2,3). Characterization of selected hvCR-K. pneumoniae via Whole-genome sequencing. RESULTS: Phenotypic colistin-resistance was 28% among CPR-Gram-negative isolates of which 90% of CR-isolates displayed MDR profile with overall low plasmid-mediated colistin resistance (mcr-2 = 9.4%;mcr-3 = 6%). Although K. pneumoniae isolates showed the highest phenotypic colistin-resistance (51%) however, relatively low plasmid-mediated gene-carriage (mcr-2 = 11.5%;mcr-3 = 3.4%) pointed toward other mechanisms of colistin-resistance. mcr-negative CR-K. pneumoniae displaying hv-phenotype were subjected to WGS. In-silico analysis detected 7-novel mutations in lipid-A modification genes includes eptA(I38V; V50L; A135P), opgE(M53L; T486A; G236S), and arnD(S164P) in addition to several non-synonymous mutations in lipid-A modification genes conferring resistance to colistin. Insertion of 6.6-kb region harboring putative-PEA-encoding gene(yjgX) was detected for the first time in K. pneumoniae (hvCRKP4771). In-silico analysis further confirmed the acquisition of not only MDR determinants but several hypervirulent-determinants displaying a convergent phenotype. CONCLUSION: overall high prevalence of phenotypic colistin resistance but low mcr-gene carriage suggested complex chromosomal mediated resistance mechanism especially in K. pneumoniae isolates. The presence of novel mutations in lipid-A modification genes and the acquisition of putative-PEA-encoding gene by hvCR-K. pneumoniae points toward the role of chromosomal determinants conferring resistance to colistin in the absence of mcr-genes.
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Colistina , Farmacorresistencia Bacteriana , Bacterias Gramnegativas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Colistina/farmacología , Colistina/uso terapéutico , Farmacorresistencia Bacteriana/genética , Pruebas de Sensibilidad Microbiana , Centros de Atención TerciariaRESUMEN
Cisplatin is ranked as one of the most powerful and commonly prescribed anti-tumor chemotherapeutic agents which improve survival in many solid tumors including non-small cell lung cancer. However, the treatment of advanced lung cancer is restricted due to chemotherapy resistance. Here, we developed and investigated survivin promoter regulating conditionally replicating adenovirus (CRAd) for its anti-tumor potential alone or in combination with cisplatin in two lung cancer cells, H23, H2126, and their resistant cells, H23/CPR, H2126/CPR. To measure the expression of genes which regulate resistance, adenoviral transduction, metastasis, and apoptosis in cancer cells, RT-PCR and Western blotting were performed. The anti-tumor efficacy of the treatments was evaluated through flow cytometry, MTT and transwell assays. This study demonstrated that co-treatment with cisplatin and CRAd exerts synergistic anti-tumor effects on chemotherapy sensitive lung cancer cells and monotherapy of CRAd could be a practical approach to deal with chemotherapy resistance. Combined treatment induced stronger apoptosis by suppressing the anti-apoptotic molecule Bcl-2, and reversed epithelial to mesenchymal transition. In conclusion, cisplatin synergistically increased the tumor-killing of CRAd by (1) increasing CRAd transduction via enhanced CAR expression and (2) increasing p53 dependent or independent apoptosis of lung cancer cell lines. Also, CRAd alone proved to be a very efficient anti-tumor agent in cancer cells resistant to cisplatin owing to upregulated CAR levels. In an exciting outcome, we have revealed novel therapeutic opportunities to exploit intrinsic and acquired resistance to enhance the therapeutic index of anti-tumor treatment in lung cancer.
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Antineoplásicos/farmacología , Carcinoma/metabolismo , Cisplatino/farmacología , Neoplasias Pulmonares/metabolismo , Virus Oncolíticos/fisiología , Replicación Viral , Adenoviridae/fisiología , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Células HEK293 , Humanos , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
The present study was conducted to investigate the quality and efficacy of commercially available preparations of tylosin and doxycycline available in the local market at Peshawar for poultry. In vitro and in vivo, tests were conducted to check the quality of these antimicrobial drugs. In vitro quality control test was performed by High performance liquid chromatographic (HPLC) and micro dilution method. In vivo, efficacy of the test drugs was checked in broilers infected with Mycoplasma gallisepticum. Results of HPLC indicated that test drug-2 contains doxycycline hydrochloride within specified limits but contain high quantity of active ingredient (Tylosin tartrate 120%). Recovery percentage of test drugs (3, 4, 5) were below the pharmacopoeial limit, which contained low quantity of tylosin tartrate (85%, 87.5%, 85%) respectively however, percent recovery of doxycycline were in the appropriate limits. All the tested drugs were effective against Mycoplasma gallisepticum and showed minimum inhibitory concentration (MIC) at 1.9µg/ml. The in vivo result indicated that all tested drugs decreased morbidity and mortality in infected chicks. The birds treated with test drugs (3 and 5) showed mortality of 9.5%, which was slightly higher than the other test groups. The current study suggested that there are incidences of substandard drugs in Pakistan and the drug regularity authorities should take strict actions against the manufacturing companies.
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Doxiciclina/análisis , Doxiciclina/farmacología , Infecciones por Mycoplasma/tratamiento farmacológico , Mycoplasma/efectos de los fármacos , Tilosina/análisis , Tilosina/farmacología , Animales , Antibacterianos/análisis , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Pollos , Doxiciclina/uso terapéutico , Pruebas de Sensibilidad Microbiana , Infecciones por Mycoplasma/veterinaria , Control de Calidad , Tilosina/uso terapéutico , Drogas Veterinarias/análisis , Drogas Veterinarias/farmacología , Drogas Veterinarias/uso terapéuticoRESUMEN
Background The prevalence of type 2 diabetes mellitus (T2DM) and obesity is alarmingly increasing with the accessibility of the modern lifestyle. This study aimed to assess the association of obesity with T2DM among the patients visiting the Medicine Department of Ayub Teaching Hospital, Abbottabad, Pakistan. Method This hospital-based, unmatched case-control study was conducted from March 2022 to September 2022. A total of 200 patients (age ≥ 18) (100 cases and 100 controls) were recruited. Those patients with a history of T2DM were selected as cases, and those without diabetes were selected as controls after taking informed written consent. Patients with BMI ≥ 25 were considered obese. Data were collected through a non-probability convenience sampling technique using a self-structured non-validated questionnaire. Data were organized and analyzed through IBM SPSS Statistics for Windows, version 26.0 (IBM Corp., Armonk, NY). Results We found a significant positive association of obesity with T2DM with a crude odds ratio of 3.6 (95% CI: 2.0-6.6), a p-value of 0.000, and an adjusted odd ratio of 3.7 (95% CI: 1.9 - 7.1), with a p-value of 0.004 (adjusted for potential confounders, including gender, age group, stress, and status of physical activeness) using a logistic regression model. Conclusion It is concluded that obesity is strongly associated with developing T2DM and lack of physical activity, people over 45 years, and males with obesity have a higher chance of developing T2DM.
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This announcement contains the whole genome sequences of five Ackermannviridae that infect members of the Enterobacteriaceae family of bacteria. Four of the five phages were isolated using Salmonella enterica serovar Typhimurium as a bacterial host: AR2819, Sajous1, SilasIsHot, and FrontPhageNews. ChubbyThor was isolated using Shigella boydii.
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Recombinant virus-based transgene therapy has shown promising results in solid tumors. Oncolytic virotherapy is a research hotspot because of its additional immunostimulatory effects. However, metastatic malignancies require systemic virotherapy, which necessitates the use of safe and effective vehicles for drug delivery. Mesenchymal stem cells (MSCs) are good carriers because of their tumor-tropic and immune-evasive capabilities. We collated published results from pre-clinical and clinical trials to support the use of MSCs as Trojan horses for the systemic administration of recombinant viruses, with a focus on glioblastoma. The generation of modified MSCs harboring recombinant viruses could expedite bench-to-bedside transformation.
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Glioblastoma , Viroterapia Oncolítica , Virus Oncolíticos , Terapia Genética , Humanos , Viroterapia Oncolítica/métodos , Virus Oncolíticos/genética , Células MadreRESUMEN
Introduction: Members of Enterobacterales are very common pathogens, which continue to show resistance to many antibiotics. Carbapenem performed well for some time. Colistin was the final hope for the carbapenem-resistant Enterobacterales, but resistance against it has virtually tied the clinician's hands, especially when it comes to treating critically ill patients. Purpose: Detection of colistin resistance by the agar method as well as by the polymerase chain reaction (mobilized colistin resistance-1 gene) in carbapenem-resistant Enterobacterales. Materials and Methods: A cross-sectional study from Dec 2019 to Dec 2020 was conducted at the Department of Microbiology, Army Medical College, National University of Medical Sciences Rawalpindi Pakistan. Antimicrobial susceptibility of Enterobacterales was determined according to the Kirby-Bauer disc diffusion method except for colistin. Colistin agar was used, in concentrations of 2 µg/mL and 4 µg/mL. Results were interpreted according to Clinical and Laboratory Standards Institute guidelines 2020. Mobilized colistin-resistant-1 gene in the carbapenem resistant Enterobacterales was detected by performing real-time polymerase chain reaction assay. Results: Among the 172 carbapenem-resistant Enterobacterales 18 isolates were resistant using the colistin agar test. Whereas by molecular method colistin resistance was detected among 10 isolates that carried mobilized colistin resistance 1 gene, making the frequency of the MCR-1 gene 5.81%. Seventy percent of isolates were from paired blood samples. Eight patients, from whom the colistin resistant gene was isolated expired. Conclusion: Colistin resistance is a very serious issue and should not be missed in a clinical microbiology laboratory. The phenotypic agar test method is an excellent option for routine use, as it combines ease of performance with affordable cost. However, molecular methods are essential for the detection of mobilized colistin resistance gene (1-9) for epidemiological purposes.
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Aloperine is an alkaloid found in the seeds and leaves of the medicinal plant Sophora alopecuroides L. It has been used as herbal medicine in China for centuries due to its potent anti-inflammatory, antioxidant, antibacterial, and antiviral properties. Recently, aloperine has been widely investigated for its therapeutic activities. Aloperine is proven to be an effective therapeutic agent against many human pathological conditions, including cancer, viral diseases, and cardiovascular and inflammatory disorders. Aloperine is reported to exert therapeutic effects through triggering various biological processes, including cell cycle arrest, apoptosis, autophagy, suppressing cell migration, and invasion. It has also been found to be associated with the modulation of various signaling pathways in different diseases. In this review, we summarize the most recent knowledge on the modulatory effects of aloperine on various critical biological processes and signaling mechanisms, including the PI3K, Akt, NF-κB, Ras, and Nrf2 pathways. These data demonstrate that aloperine is a promising therapeutic candidate. Being a potent modulator of signaling mechanisms, aloperine can be employed in clinical settings to treat various human disorders in the future.
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Evasion of growth suppression is among the prominent hallmarks of cancer. Phosphatase and tensin homolog (PTEN) and p53 tumor-suppressive pathways are compromised in most human cancers, including glioblastoma (GB). Hence, these signaling pathways are an ideal point of focus for novel cancer therapeutics. Recombinant viruses can selectivity kill cancer cells and carry therapeutic genes to tumors. Specifically, oncolytic viruses (OV) have been successfully employed for gene delivery in GB animal models and showed potential to neutralize immunosuppression at the tumor site. However, the associated systemic immunogenicity, inefficient transduction of GB cells, and inadequate distribution to metastatic tumors have been the major bottlenecks in clinical studies. Mesenchymal stem cells (MSCs), with tumor-tropic properties and immune privilege, can improve OVs targeting. Remarkably, combining the two approaches can address their individual issues. Herein, we summarize findings to advocate the reactivation of tumor suppressors p53 and PTEN in GB treatment and use MSCs as a "Trojan horse" to carry oncolytic viral cargo to disseminated tumor beds. The integration of MSCs and OVs can emerge as the new paradigm in cancer treatment.
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Glioblastoma , Células Madre Mesenquimatosas , Viroterapia Oncolítica , Virus Oncolíticos , Animales , Glioblastoma/genética , Glioblastoma/metabolismo , Glioblastoma/terapia , Células Madre Mesenquimatosas/metabolismo , Virus Oncolíticos/genética , Virus Oncolíticos/metabolismo , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
Amplification of ubiquitin E3 ligase Smurf1 promotes degradation of PTEN leading to hyperactivation of the Akt/mTORC1 pathway. However, inhibitors of this pathway have not hitherto yielded promising results in clinical studies because of strong drug resistance. Here, we investigated Smurf1 expression in various glioblastoma (GB) cell lines and patient tissues. The therapeutic efficacy of Smurf1 silencing and Torin1 treatment was assessed in GB cells and orthotopic mouse model. We found Smurf1 loss elevates PTEN levels that interrupt the epidermal growth factor receptor pathway activity. Cotreatment with Smurf1 silencing and mTORC1/C2 inhibitor Torin1 remarkably decreased phosphorylation of Akt, and mTORC1 downstream targets 4EBP1 and S6K resulting in synergistic inhibitory effects. Smurf1 knockdown in orthotopic GB mouse model impaired tumor growth and enhanced cytotoxicity of Torin1. Together, these findings suggest a rational combination of Smurf1 inhibition and Torin1 as a promising new avenue to circumvent PI3K/Akt pathway-driven tumor progression and drug resistance.
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Camel milk is a valuable source of nutrition with a wide range of therapeutic effects. Its unique composition helps to regulate the blood glucose level. The current study is aimed to evaluate the antidiabetic and hepatoprotective effects, as well as lipid profile restoration of camel milk in the diabetic mouse model. This innovative study evaluates the therapeutic effects of camel milk in diabetic mice by simultaneous measurement of blood glucose, HbA1c, ALT, AST, TG, cholesterol, and histopathological studies. The results showed that camel milk has significantly reduced blood glucose, HbA1c (p < .001), aspartate transaminase (AST), alanine transaminase (ALT) (p < .01), triglyceride (TG), and cholesterol (p < .01), compared to that in the diabetic control group. Also, the therapeutic effects of camel milk were completely comparable with the antidiabetic drug glibenclamide. The results of this study suggest that camel milk could be used as a proper alternative treatment regimen for diabetes therapy.
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The high-grade glioma is characterized by cell heterogeneity, gene mutations, and poor prognosis. The deletions and mutations of the tumor suppressor gene PTEN (5%-40%) in glioma patients are associated with worse survival and therapeutic resistance. Characterization of unique prognosis molecular signatures by PTEN status in glioma is still unclear. This study established a novel risk model, screened optimal prognostic signatures, and calculated the risk score for the individual glioma patients with different PTEN status. Screening results revealed fourteen independent prognostic gene signatures in PTEN-wt and three in the -50PTEN-mut subgroup. Moreover, we verified risk score as an independent prognostic factor significantly correlated with tumor malignancy. Due to the higher malignancy of the PTEN-mut gliomas, we explored the independent prognostic signatures (CLCF1, AEBP1, and OS9) for a potential therapeutic target in PTEN-mut glioma. We further separated IDH wild-type glioma patients into GBM and LGG to verify the therapeutic target along with PTEN status, notably, the above screened therapeutic targets are also significant prognostic genes in both IDH-wt/PTEN-mut GBM and LGG patients. We further identified the small molecule compound (+)-JQ1 binds to all three targets, indicating a potential therapy for PTEN-mut glioma. In sum, gene signatures and risk scores in the novel risk model facilitate glioma diagnosis, prognosis prediction, and treatment.
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Glioblastoma (GB) is the most common and aggressive brain malignancy, characterized by heterogeneity and drug resistance. PTEN, a crucial tumor suppressor, exhibits phosphatase-dependent (PI3K-AKT-mTOR pathway)/independent (nucleus stability) activities to maintain the homeostatic regulation of numerous physiological processes. Premature and absolute loss of PTEN activity usually tends to cellular senescence. However, monoallelic loss of PTEN is frequently observed at tumor inception, and absolute loss of PTEN activity also occurs at the late stage of gliomagenesis. Consequently, aberrant PTEN homeostasis, mainly regulated at the post-translational level, renders cells susceptible to tumorigenesis and drug resistance. Ubiquitination-mediated degradation or deregulated intracellular localization of PTEN hijacks cell growth rheostat control for neoplastic remodeling. Functional inactivation of PTEN mediated by the overexpression of ubiquitin ligases (E3s) renders GB cells adaptive to PTEN loss, which confers resistance to EGFR tyrosine kinase inhibitors and immunotherapies. In this review, we discuss how glioma cells develop oncogenic addiction to the E3s-PTEN axis, promoting their growth and proliferation. Antitumor strategies involving PTEN-targeting E3 ligase inhibitors can restore the tumor-suppressive environment. E3 inhibitors collectively reactivate PTEN and may represent next-generation treatment against deadly malignancies such as GB.
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The importance of microbiota paves the way to use microbial cells as medicines to treat pathobiomic diseases. This study reported the fabrication of probiotic (Enterococcus mundtii QAUEM2808)-functionalized nanocomposite scaffolds of poly(vinyl alcohol)/poly(vinylpyrrolidone)/glycerol via electrospinning. Scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis resolved the living composite structure and supported the encapsulation of E. mundtii throughout the nanostructured (318 ± 12 nm) fibers of bioscaffold membranes. The shelf life evaluation of 4-week-old samples supported that bioscaffolds showed an enhancement in probiotic survival count by 2.78 ± 0.10 log10 colony-forming units (cfu) versus counterpart biodispersion. The swelling and antagonistic evaluation showed that a bioscaffold is degradable in a simulated wound fluid which is essential for activation of probiotic strains to antagonize infection-causing Gram-positive and Gram-negative pathogens. A second-degree contact burn was made on the dorsum of male BALB/c mice (n = 30). The wounds were left open for 2 days to mimic burn contamination, and the mice were randomized into negative (untreated), positive (silver sulfadiazine cream), vehicle (biodispersion and nanoscaffold), and experimental bioscaffold groups (n = 6/group). These treatments were applied on 2, 6, 10, and 14 days postburn. A comparative wound closure, histopathology, and wound microbial evaluation demonstrated that the bioscaffolds accelerate epithelialization, collagen deposition, and hair follicle formation, inhibit harmful bacteria, and provide interference benefits. In particular, the probiotic active bioscaffold membrane could serve as a novel candidate to control infections and speed up the healing of burn wounds.
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N6-Methyladenosine (m6A) is the most prevalent internal modification that occurs in the mRNA of eukaryotes and plays a vital role in the post-transcriptional regulation. Recent studies highlighted the biological significance of m6A modification in the nervous system, and its dysregulation has been shown to be related to degenerative and neurodevelopmental diseases. Parkinson's disease (PD) is a common age-related neurological disorder with its pathogenesis still not fully elucidated. Reports have shown that epigenetic mechanisms including DNA methylation and histone acetylation, which alter gene expression, are associated with PD. In this study, we found that global m6A modification of mRNAs is down-regulated in 6-OHDA-induced PC12 cells and the striatum of PD rat brain. To further explore the relationship between m6A mRNA methylation and molecular mechanism of PD, we decreased m6A in dopaminergic cells by overexpressing a nucleic acid demethylase, FTO, or by m6A inhibitor. The results showed that m6A reduction could induce the expression of N-methyl-d-aspartate (NMDA) receptor 1, and elevate oxidative stress and Ca2+ influx, resulting in dopaminergic neuron apoptosis. Collectively, m6A modification may play a vital role in the death of dopaminergic neuron, which provides a novel view of mRNA methylation to understand the epigenetic regulation of Parkinson's disease.
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Adenosina/análogos & derivados , Muerte Celular/fisiología , Neuronas Dopaminérgicas/fisiología , ARN Mensajero/metabolismo , Adenosina/antagonistas & inhibidores , Adenosina/fisiología , Animales , Apoptosis/fisiología , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Regulación hacia Abajo/fisiología , Epigénesis Genética/fisiología , Masculino , Metilación , Oxidopamina/farmacología , Células PC12 , Enfermedad de Parkinson/fisiopatología , Ratas , Ratas Sprague-Dawley , Simpaticolíticos/farmacologíaRESUMEN
Salsolinol (1-methyl-6,7-dihydroxy-1,2,3,4-tetrahydroisoquinoline), a derivate of dopamine, is suspected to be the most probable neurotoxin in the degeneration of dopaminergic neurons. Numerous hypotheses regarding its pathophysiological roles have been raised, especially related to Parkinson's disease and alcohol addiction. In the mammalian brain, salsolinol may be enzymatically synthesized by salsolinol synthase from dopamine and acetaldehyde. However, the direct evidence of its biosynthesis was still missing. In this study, we purified salsolinol synthase from rat brain by a systematical procedure involving acid precipitation, ultrafiltration, and hydrophilic interaction chromatography. The molecular weight of salsolinol synthase determined by MALDI-TOF MS is 8622.29 Da, comprising 77 amino acids (MQIFVKTLTG KTITLEVEPS DTIKNVKAKI QDKEGIPPDQ QRLIFAGKQL EDGRTLSDYN IQKKSTLHLV LRLRVDY). Homology analysis showed that the enzyme is a ubiquitin-like protein, with a difference of four amino acids, which suggests it is a novel protein. After it was overexpressed in eukaryotic cells, the production of salsolinol was significantly increased as compared with control, confirming the catalytic function of this enzyme. To our knowledge, it is the first systematic purification and sequencing of salsolinol synthase. Together, this work reveals a formerly anonymous protein and urges further exploration of its possible prognostic value and implications in Parkinson's disease and other related disorders.
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Encéfalo/metabolismo , Isoquinolinas/metabolismo , Animales , Encéfalo/efectos de los fármacos , Dopamina/metabolismo , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/metabolismo , Isoquinolinas/química , Neurotoxinas/metabolismo , Neurotoxinas/farmacología , Óxido Nítrico Sintasa/efectos de los fármacos , Óxido Nítrico Sintasa/metabolismo , Enfermedad de Parkinson/metabolismo , Ratas , Tetrahidroisoquinolinas/farmacologíaRESUMEN
Salsolinol is an endogenous neurotoxin derived from dopamine, and has been proved to cause the apoptosis of the dopaminergic neurons involved in the pathogenesis of Parkinson's disease (PD). Salsolinol synthase is the key enzyme in the biosynthesis of salsolinol, and its activity exists in most regions of rat brain. However, the activity distribution and its catalyzed function in vivo are still unknown. On the basis of the chromatographic assay established previously, we investigated the activity of salsolinol synthase and salsolinol production in both cell and rat model of PD induced by 6-hydroxydopamine (6-OHDA). The results show that the enzymatic activity increases in cell model and in the striatum region of PD rat brain. Nevertheless, there is a reduction of activity in hippocampus, cortex, and midbrain of PD model when compared with control. Conversely, the level of salsolinol was significantly increased in the midbrain region. Together, these results indicate the relationship between the oxidative stress induced by 6-OHDA and the activity of salsolinol synthase, suggesting the correlation of the endogenous neurotoxin and Parkinson's disease. Further research will provide more evidence and clarity on the function of Sal synthase.