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1.
Nat Commun ; 15(1): 8071, 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39277579

RESUMEN

The ATP-independent chaperone SurA protects unfolded outer membrane proteins (OMPs) from aggregation in the periplasm of Gram-negative bacteria, and delivers them to the ß-barrel assembly machinery (BAM) for folding into the outer membrane (OM). Precisely how SurA recognises and binds its different OMP clients remains unclear. Escherichia coli SurA comprises three domains: a core and two PPIase domains (P1 and P2). Here, by combining methyl-TROSY NMR, single-molecule Förster resonance energy transfer (smFRET), and bioinformatics analyses we show that SurA client binding is mediated by two binding hotspots in the core and P1 domains. These interactions are driven by aromatic-rich motifs in the client proteins, leading to SurA core/P1 domain rearrangements and expansion of clients from collapsed, non-native states. We demonstrate that the core domain is key to OMP expansion by SurA, and uncover a role for SurA PPIase domains in limiting the extent of expansion. The results reveal insights into SurA-OMP recognition and the mechanism of activation for an ATP-independent chaperone, and suggest a route to targeting the functions of a chaperone key to bacterial virulence and OM integrity.


Asunto(s)
Proteínas Portadoras , Proteínas de Escherichia coli , Escherichia coli , Chaperonas Moleculares , Isomerasa de Peptidilprolil , Adenosina Trifosfato/metabolismo , Transportadoras de Casetes de Unión a ATP/metabolismo , Transportadoras de Casetes de Unión a ATP/química , Transportadoras de Casetes de Unión a ATP/genética , Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas de la Membrana Bacteriana Externa/genética , Proteínas de la Membrana Bacteriana Externa/química , Sitios de Unión , Proteínas Portadoras/metabolismo , Escherichia coli/metabolismo , Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/química , Transferencia Resonante de Energía de Fluorescencia , Modelos Moleculares , Chaperonas Moleculares/metabolismo , Isomerasa de Peptidilprolil/metabolismo , Isomerasa de Peptidilprolil/genética , Unión Proteica , Dominios Proteicos , Pliegue de Proteína
2.
Adv Tech Stand Neurosurg ; 53: 79-92, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39287804

RESUMEN

OBJECTIVE: Endoscopic surgery has emerged in the recent years as an alternative to the conventional microsurgical approaches for removal of the deep-seated brain and intraventricular tumors. Endoport has enhanced the tumor access and visualization without any significant brain retraction. In this chapter, we describe the surgical technique of the endoscopic excision of the deep-seated intra-axial brain tumors using tubular retraction system with review of the literature. METHODS: The endoscopic endoport technique that we use at our institution for the surgical management of intraventricular and intraparenchymal brain tumors has been described in details with illustrations. RESULTS: Results from the literature review of brain parenchymal and intraventricular port surgery were analyzed, and the feasibility and safety of this technique were discussed. Surgical complication avoidance and management were highlighted. The port technique offers numerous potential advantages, including: (1) reducing focal brain injury by distributing retraction forces homogenously; (2) minimizing white matter disruption and the risk of fascicles injury during cannulation; (3) ensuring stability of the surgical corridor during the procedure; (4) preventing inadvertent expansion of the corticectomy and white fiber tract dissection throughout surgery; (5) protecting the surrounding tissues against iatrogenic injuries caused by instrument entry and reentry. CONCLUSION: The endoport-assisted endoscopic technique is a safe and minimally invasive method that offers an effective alternative option for resection of intraventricular and parenchymal brain lesions. Excellent outcome comparable to other surgical approaches can be achieved with acceptable complications.


Asunto(s)
Neoplasias Encefálicas , Humanos , Neoplasias Encefálicas/cirugía , Neoplasias Encefálicas/patología , Neuroendoscopía/métodos , Neuroendoscopía/instrumentación , Neoplasias del Ventrículo Cerebral/cirugía , Neoplasias del Ventrículo Cerebral/patología , Masculino , Femenino , Procedimientos Neuroquirúrgicos/métodos , Persona de Mediana Edad , Adulto
3.
Biochimie ; 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39299536

RESUMEN

The aryl hydrocarbon receptor interacting protein (AIP) is a cytoplasmic molecular co-chaperone and tumour suppressor that assists in protein stability and complex formation involving the aryl hydrocarbon receptor. Germline mutations in the AIP gene predispose to pituitary tumourigenesis with patients exhibiting an aggressive clinical phenotype. Full length AIP harbouring N-domain mutations (R9Q, R16H, V49M and K103R) were purified from E.coli utilizing a methodology that maintained structural integrity and monomeric stability. Mutations did not significantly affect the thermal stability of the protein and caused no overall disruptive effect in the protein structure. The mutations studied lowered the binding affinity of AIP towards two of its binding partners; heat shock protein 90ß and phosphodiesterase 4A5 (PDE4A5). The inhibition of phosphodiesterase activity by AIP was also greatly reduced by all mutants. While previously published data has mainly concentrated on the tetratricopeptide repeats of the C-domain of AIP, we present clear evidence that AIP N-domain mutations play a significant role in two protein:protein interactions with partner proteins. The complex interactome of AIP suggests that any observable change in one or more of its binding partners cannot be disregarded as it may have repercussions on other biochemical pathways.

4.
Proc Natl Acad Sci U S A ; 121(34): e2315006121, 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39133842

RESUMEN

Amyloid formation by α-synuclein (αSyn) occurs in Parkinson's disease, multiple system atrophy, and dementia with Lewy bodies. Deciphering the residues that regulate αSyn amyloid fibril formation will not only provide mechanistic insight but may also reveal targets to prevent and treat disease. Previous investigations have identified several regions of αSyn to be important in the regulation of amyloid formation, including the non-amyloid-ß component (NAC), P1 region (residues 36 to 42), and residues in the C-terminal domain. Recent studies have also indicated the importance of the N-terminal region of αSyn for both its physiological and pathological roles. Here, the role of residues 2 to 7 in the N-terminal region of αSyn is investigated in terms of their ability to regulate amyloid fibril formation in vitro and in vivo. Deletion of these residues (αSynΔN7) slows the rate of fibril formation in vitro and reduces the capacity of the protein to be recruited by wild-type (αSynWT) fibril seeds, despite cryo-EM showing a fibril structure consistent with those of full-length αSyn. Strikingly, fibril formation of αSynΔN7 is not induced by liposomes, despite the protein binding to liposomes with similar affinity to αSynWT. A Caenorhabditis elegans model also showed that αSynΔN7::YFP forms few puncta and lacks motility and lifespan defects typified by expression of αSynWT::YFP. Together, the results demonstrate the involvement of residues 2 to 7 of αSyn in amyloid formation, revealing a target for the design of amyloid inhibitors that may leave the functional role of the protein in membrane binding unperturbed.


Asunto(s)
Amiloide , Caenorhabditis elegans , alfa-Sinucleína , alfa-Sinucleína/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/química , Amiloide/metabolismo , Caenorhabditis elegans/metabolismo , Animales , Humanos , Lípidos/química , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/genética , Enfermedad de Parkinson/patología
5.
Adv Tech Stand Neurosurg ; 52: 63-72, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39017786

RESUMEN

OBJECTIVE: Transcortical approaches using a spatula-based retraction system have traditionally been used for the microsurgical resection of deep-seated intraventricular and parenchymal brain tumors. Recently, transparent cylindrical or tubular retractors have been developed to provide a stable corridor to access deeper brain lesions and perform bimanual microsurgical resection. The flexible endoports minimize brain retraction injury during surgery and, along with the superior vision of endoscopes, offer several advantages over standard microsurgery. In this chapter, we describe the surgical technique of the endoport-guided endoscopic excision of deep-seated intraaxial brain tumors. METHODS: The endoscopic endoport technique that we use at our institution for the surgical management of intraventricular and intraparenchymal brain tumors has been described in detail with illustrative cases. RESULTS: Results from the literature review of intraventricular and intraparenchymal port surgery were analyzed, and the feasibility and safety of this technique were discussed. Surgical complication avoidance and management were highlighted. The port technique offers numerous potential advantages, including (1) reducing focal brain injury by distributing retraction forces homogenously, (2) minimizing white matter disruption and the risk of fascicle injury during cannulation, (3) ensuring the stability of the surgical corridor during the procedure, (4) preventing inadvertent expansion of the corticectomy and white fiber tract dissection throughout surgery, and (5) protecting the surrounding tissues against iatrogenic injuries caused by instrument entry and reentry. CONCLUSION: The endoport-assisted endoscopic technique is safe and offers an effective alternative option for the resection of intraventricular and intraparenchymal lesions.


Asunto(s)
Neoplasias Encefálicas , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Encefálicas/cirugía , Neuroendoscopía/métodos , Neuroendoscopía/instrumentación , Procedimientos Neuroquirúrgicos/métodos
6.
J Addict Med ; 18(3): 345-347, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38329815

RESUMEN

BACKGROUND: Federal regulations restrict methadone for opioid use disorder (OUD) treatment to licensed opioid treatment programs (OTPs). However, providers in other settings can administer methadone for opioid withdrawal under the "72-hour rule" while linking to further care. Prior work has demonstrated that methadone initiation in a low-barrier bridge clinic is associated with high OTP linkage and 1-month retention rates. We describe 2 other novel applications of the 72-hour rule in which methadone withdrawal management facilitated linkage to inpatient hospitalization and outpatient buprenorphine induction. CASE PRESENTATIONS: Patient 1 was a 46-year-old woman with OUD complicated by serious injection-related infections. Severe opioid withdrawal limited her ability to tolerate emergency department wait times and receive inpatient care. We administered methadone for opioid withdrawal in an outpatient bridge clinic immediately before emergency department referral; this enabled hospital admission for intravenous antibiotics and anticoagulation. Patient 2 was a 36-year-old man with OUD desiring buprenorphine treatment. He had been unable to complete traditional buprenorphine induction without experiencing precipitated withdrawal. Thus, we recommended a low-dose buprenorphine induction overlapping with a full opioid agonist. Given the patient's preference to stop using fentanyl immediately, he received 72 hours of methadone for withdrawal treatment during the induction phase and successfully transitioned to buprenorphine without significant concomitant fentanyl use. CONCLUSION: In addition to facilitating OTP linkage, on-demand 72-hour methadone administration for opioid withdrawal can reduce barriers to acute medical care and buprenorphine treatment.


Asunto(s)
Buprenorfina , Metadona , Tratamiento de Sustitución de Opiáceos , Trastornos Relacionados con Opioides , Humanos , Analgésicos Opioides/administración & dosificación , Buprenorfina/administración & dosificación , Metadona/administración & dosificación , Metadona/uso terapéutico , Tratamiento de Sustitución de Opiáceos/métodos , Trastornos Relacionados con Opioides/tratamiento farmacológico , Síndrome de Abstinencia a Sustancias/tratamiento farmacológico
7.
Reprod Sci ; 31(5): 1420-1428, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38294668

RESUMEN

Oocyte cryopreservation is offered to women of various age groups for both health and social reasons. Oocytes derived from either controlled ovarian stimulation or in vitro maturation (IVM) are cryopreserved via vitrification. As maternal age is a significant determinant of oocyte quality, there is limited data on the age-related susceptibility of oocytes to the vitrification-warming procedure alone or in conjunction with IVM. In the present study, metaphase II oocytes obtained from 2, 6, 9, and 12 month old Swiss albino mice either by superovulation or IVM were used. To understand the association between maternal age and oocyte cryotolerance, oocytes were subjected to vitrification-warming and compared to non vitrified sibling oocytes. Survived oocytes were evaluated for mitochondrial potential, spindle integrity, relative expression of spindle checkpoint protein transcripts, and DNA double-strand breaks. Maturation potential and vitrification-warming survival were significantly affected (p < 0.001 and p < 0.05, respectively) in ovulated oocytes from the advanced age group but not in IVM oocytes. Although vitrification-warming significantly increased spindle abnormalities in ovulated oocytes from advanced maternal age (p < 0.01), no significant changes were observed in IVM oocytes. Furthermore, Bub1 and Mad2 transcript levels were significantly higher in vitrified-warmed IVM oocytes (p < 0.05). In conclusion, advanced maternal age can have a negative impact on the cryosusceptibility of ovulated oocytes but not IVM oocytes in mice.


Asunto(s)
Criopreservación , Técnicas de Maduración In Vitro de los Oocitos , Edad Materna , Oocitos , Vitrificación , Animales , Oocitos/fisiología , Femenino , Ratones , Criopreservación/métodos , Proteínas Mad2/metabolismo , Huso Acromático/fisiología , Huso Acromático/metabolismo , Roturas del ADN de Doble Cadena , Proteínas Serina-Treonina Quinasas/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas de Ciclo Celular/metabolismo , Proteínas de Ciclo Celular/genética , Supervivencia Celular/fisiología
8.
Braz. j. biol ; 83: 1-7, 2023. ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1468894

RESUMEN

Staphylococcus aureus is an important foodborne pathogen associated to food intoxication and other multiple infections in human being. Its presence in salted food is a serious issue due to its salt tolerance potential. A study was conducted to analyze the presence of enterotoxins producing drug resistance S. aureus in salted sea fish from Gwadar. Freshly persevered samples (n=50) of salted fish were subjected to analyze the presence of S. aureus using 16S rRNA and Nuc genes primers. The isolates were then evaluated for drug resistance and enterotoxins producing potential using specific primers for MecA (methicillin resistance gene), (SEA) staphylococcal enterotoxin A and (SEB) staphylococcal enterotoxin B genes. Total 13/50 (26%) of the samples were found positive for the presence of S. aureus, preliminary confirmed with biochemical profiling and finally with the help of target genes presence. The isolates were found showing 100% resistant to methicillin, which were molecularly confirmed by the presence of MecA gene present in genome. The isolates 5/13 (38%) were positive for SEA and 3/13 (23%) for SEB genes, whereas 2/13 (15%) were confirmed having both SEA and SEB genes in its genome. It was also confirmed that all the isolates were capable to form biofilm over the glass surfaces. It was concluded that the study confirmed the presence of enterotoxigenic methicillin resistance Staphylococcus aurous (MRSA) in salted fish product, that poses gross food safety concern. Preventive and control measures are necessary to handle this serious food safety concern.


Staphylococcus aureus é um importante patógeno de origem alimentar associado à intoxicação alimentar e outras infecções múltiplas em seres humanos. Sua presença em alimentos salgados é um problema sério devido ao seu potencial de tolerância ao sal. Um estudo foi realizado para analisar a presença de enterotoxinas produtoras de resistência a drogas S. aureus em peixes salgados do mar de Gwadar. Amostras recém-perseveradas (n = 50) de peixes salgados foram submetidas à análise da presença de S. aureus usando os primers dos genes 16S rRNA e Nuc. Os isolados foram então avaliados quanto à resistência a drogas e potencial de produção de enterotoxinas usando primers específicos para os genes MecA (gene de resistência à meticilina), (SEA) enterotoxina A estafilocócica e (SEB) enterotoxina B estafilocócica genes. Um total de 13/50 (26%) das amostras foi considerado positivas para a presença de S. aureus, confirmadas preliminarmente com perfis bioquímicos e finalmente com a ajuda da presença de genes-alvo. Os isolados foram encontrados com 100% de resistência à meticilina, os quais foram confirmados molecularmente pela presença do gene MecA no genoma. Os isolados 5/13 (38%) foram positivos para SEA e 3/13 (23%) para genes SEB, enquanto 2/13 (15%) foram confirmados tendo os genes SEA e SEB em seu genoma. Também foi verificado que todos os isolados foram capazes de formar biofilme sobre as superfícies de vidro. Concluiu-se que o estudo confirmou a presença de Staphylococcus aurous resistente à meticilina enterotoxigênica (MRSA) em produtos de peixe salgado, o que representa uma grande preocupação para a segurança alimentar. Medidas preventivas e de controle são necessárias para lidar com essa grave preocupação com a segurança alimentar.


Asunto(s)
Animales , Enfermedades Transmitidas por los Alimentos/prevención & control , Inocuidad de los Alimentos , Peces/genética , Staphylococcus aureus Resistente a Meticilina/patogenicidad
9.
Braz. j. biol ; 832023.
Artículo en Inglés | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469110

RESUMEN

Abstract Staphylococcus aureus is an important foodborne pathogen associated to food intoxication and other multiple infections in human being. Its presence in salted food is a serious issue due to its salt tolerance potential. A study was conducted to analyze the presence of enterotoxins producing drug resistance S. aureus in salted sea fish from Gwadar. Freshly persevered samples (n=50) of salted fish were subjected to analyze the presence of S. aureus using 16S rRNA and Nuc genes primers. The isolates were then evaluated for drug resistance and enterotoxins producing potential using specific primers for MecA (methicillin resistance gene), (SEA) staphylococcal enterotoxin A and (SEB) staphylococcal enterotoxin B genes. Total 13/50 (26%) of the samples were found positive for the presence of S. aureus, preliminary confirmed with biochemical profiling and finally with the help of target genes presence. The isolates were found showing 100% resistant to methicillin, which were molecularly confirmed by the presence of MecA gene present in genome. The isolates 5/13 (38%) were positive for SEA and 3/13 (23%) for SEB genes, whereas 2/13 (15%) were confirmed having both SEA and SEB genes in its genome. It was also confirmed that all the isolates were capable to form biofilm over the glass surfaces. It was concluded that the study confirmed the presence of enterotoxigenic methicillin resistance Staphylococcus aurous (MRSA) in salted fish product, that poses gross food safety concern. Preventive and control measures are necessary to handle this serious food safety concern.


Resumo Staphylococcus aureus é um importante patógeno de origem alimentar associado à intoxicação alimentar e outras infecções múltiplas em seres humanos. Sua presença em alimentos salgados é um problema sério devido ao seu potencial de tolerância ao sal. Um estudo foi realizado para analisar a presença de enterotoxinas produtoras de resistência a drogas S. aureus em peixes salgados do mar de Gwadar. Amostras recém-perseveradas (n = 50) de peixes salgados foram submetidas à análise da presença de S. aureus usando os primers dos genes 16S rRNA e Nuc. Os isolados foram então avaliados quanto à resistência a drogas e potencial de produção de enterotoxinas usando primers específicos para os genes MecA (gene de resistência à meticilina), (SEA) enterotoxina A estafilocócica e (SEB) enterotoxina B estafilocócica genes. Um total de 13/50 (26%) das amostras foi considerado positivas para a presença de S. aureus, confirmadas preliminarmente com perfis bioquímicos e finalmente com a ajuda da presença de genes-alvo. Os isolados foram encontrados com 100% de resistência à meticilina, os quais foram confirmados molecularmente pela presença do gene MecA no genoma. Os isolados 5/13 (38%) foram positivos para SEA e 3/13 (23%) para genes SEB, enquanto 2/13 (15%) foram confirmados tendo os genes SEA e SEB em seu genoma. Também foi verificado que todos os isolados foram capazes de formar biofilme sobre as superfícies de vidro. Concluiu-se que o estudo confirmou a presença de Staphylococcus aurous resistente à meticilina enterotoxigênica (MRSA) em produtos de peixe salgado, o que representa uma grande preocupação para a segurança alimentar. Medidas preventivas e de controle são necessárias para lidar com essa grave preocupação com a segurança alimentar.

10.
bioRxiv ; 2023 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38187764

RESUMEN

Transmembrane ß-barrels (TMBs) are widely used for single molecule DNA and RNA sequencing and have considerable potential for a broad range of sensing and sequencing applications. Current engineering approaches for nanopore sensors are limited to naturally occurring channels such as CsgG, which have evolved to carry out functions very different from sensing, and hence provide sub-optimal starting points. In contrast, de novo protein design can in principle create an unlimited number of new nanopores with any desired properties. Here we describe a general approach to the design of transmembrane ß-barrel pores with different diameter and pore geometry. NMR and crystallographic characterization shows that the designs are stably folded with structures close to the design models. We report the first examples of de novo designed TMBs with 10, 12 and 14 stranded ß-barrels. The designs have distinct conductances that correlate with their pore diameter, ranging from 110 pS (~0.5 nm pore diameter) to 430 pS (~1.1 nm pore diameter), and can be converted into sensitive small-molecule sensors with high signal to noise ratio. The capability to generate on demand ß-barrel pores of defined geometry opens up fundamentally new opportunities for custom engineering of sequencing and sensing technologies.

11.
Kathmandu Univ Med J (KUMJ) ; 21(84): 372-375, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-39212010

RESUMEN

Background Accessory (supernumerary bone) is small irregular worm like bone. These bones are also known as wormian bone. Accessory bone develops when additional ossification centers appear and form extra bones. Many bones develop from several ossification centers of ossification and these separate parts normally fuse. Sometimes one of these centers fails to fuse with main bone. Circumscribed areas of bone are seen along the sutures of the cranium where flat bones about, particularly related to parietal bone. Objective To investigate presence and to determine morphologic and morphometric characteristics of wormian (sutural) bones. Method The study was conducted on 25 dry human skulls with unknown gender, ethnicity and race in Department of Anatomy, School of Basic Sciences, Kailashnagar, Bharatpur-5, Chitwan Nepal. The study was conducted on 25 dry human skulls with unknown gender, ethnicity and race in Department of Anatomy, School of Basic Sciences, Kailashnagar, Bharatpur-5, Chitwan Nepal. The deformed skull and skull of pediatrics age group are excluded. The location, shape, number and side of Wormian bone are determined. The SPSS 20 program and descriptive statistical method analysis were used for data analysis. Result Total 25 adult dry skulls were observed in the study. Both sides of skull were observed. Out of 25 skulls Wormian bones are not found in left sided three lambdoidal suture (four percent). Conclusion The knowledge of Wormian bones plays a major role for the neurosurgeons, neuroanatomists, radiologists, forensic experts and anthropologist. Presence of few bones are normal. But multiple Wormian bones need attention as it may have underlying skeletal or central nervous system pathology. In radiographs they mimic fracture lines. Wormian bone at pterion may produce complications in neurosurgical procedures like burr holes.


Asunto(s)
Cráneo , Humanos , Nepal , Cráneo/anatomía & histología , Cráneo/diagnóstico por imagen , Masculino , Femenino , Suturas Craneales/anatomía & histología , Suturas Craneales/diagnóstico por imagen , Adulto
12.
Biomed Res Int ; 2022: 1640193, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35941980

RESUMEN

Habb-e-Suranjan (HES), an Unani formulation, has been studied for its anti-inflammatory properties in both in vitro and in vivo experiments. HES is recommended for arthritis, gout, and joint pain. The current endeavor is an attempt to put it to the test and verify its efficacy scientifically. It was tested for DPPH, hydroxyl, and nitric oxide scavenging activities. It was shown that HES had the greatest TAC and FRAC values when compared to catechin and ascorbic acid. HES exhibited DPPH and hydroxyl radical scavenging activity that was dose-dependent. Incubation of sodium nitroprusside solutions in PBS at 25°C for 150 min resulted in the production of nitric oxide. Nitric oxide production was effectively decreased by HES. Anti-inflammatory medications boosted the migration of PMN cells toward the chemoattractant FMLP in an agarose experiment of PMN chemotaxis. In carrageenan-induced rat paw edema, in the HES-treated group, paw thickness was 3.021 ± 0.084 at t = 0, but it showed an increase in paw inflammation after one hour, i.e., 3.195 ± 0.082 cm which again showed a decrease in paw thickness up to 4th hour, i.e., 3.018 ± 0.078, 2.98 ± 0.032, and 2.684 ± 0.061 at t = 2, 3, and 4, respectively. It showed again getting back to the normal thickness of paw at t = 24 hrs, i.e., 3.029 ± 0.118 cm. It is concluded that the formulation is potent enough and can be used effectively for the treatment of inflammation and associated health issues. Moreover, there is much scope to evaluate its effectiveness using different in vitro and in vivo models.


Asunto(s)
Óxido Nítrico , Extractos Vegetales , Animales , Antiinflamatorios/uso terapéutico , Carragenina/efectos adversos , Edema/inducido químicamente , Edema/tratamiento farmacológico , Inflamación/tratamiento farmacológico , Extractos Vegetales/uso terapéutico , Ratas
13.
Eur J Pharmacol ; 928: 175095, 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-35728626

RESUMEN

Snake envenomation leads to the formation of damage-associated molecular patterns (DAMPs), which are mediated by endogenous intracellular molecules. These are recognized by pattern-recognition receptors (PRRs) and can induce sterile inflammation. AIMS: In the present study, we aim at understanding the mechanisms involved in DAMPs induced sterile inflammation to unravel the novel therapeutic strategies for treating snake bites. The potential of benzodiazepinone derivatives to act against snake venom induced inflammation has been explored in the present investigation. MAIN METHODS: Three compounds VA 17, VA 43 and PA 03 were taken from our library of synthetic compounds. Oxidative stress markers such as lipid peroxidation, superoxide and nitric oxide were measured along with the analysis of DAMPs (IL6, HMGB1, vWF, S100b and HSP70). These compounds have been docked using molecular docking against the snake venom PLA2 structure (PDB code: 1OXL). KEY FINDINGS: The compounds have been found to effectively neutralize viper and cobra venoms induced lethal activity both ex vivo and in vivo. The compounds have also neutralized the viper venom induced hemorrhagic, coagulant, anticoagulant reactions as well as inflammation. The fold of protection have always been found to be higher in case of ex vivo than in in vivo. These compounds have neutralized the venom induced DAMPs as exhibited by IL6, HMGB1, vWF, S100b and HSP70. The fold of neutralization is found to be higher in VA 43. SIGNIFICANCE: The identified compounds could be used as potential candidates for developing treatment of snakebites in areas where antiserums are not yet available.


Asunto(s)
Proteína HMGB1 , Mordeduras de Serpientes , Animales , Antivenenos/química , Antivenenos/farmacología , Antivenenos/uso terapéutico , Inflamación/inducido químicamente , Inflamación/tratamiento farmacológico , Interleucina-6 , Simulación del Acoplamiento Molecular , Mordeduras de Serpientes/tratamiento farmacológico , Venenos de Víboras , Factor de von Willebrand
14.
Mater Chem Phys ; 282: 125803, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35153357

RESUMEN

The excellent strategy to mitigate the spread of the COVID-19 pandemic is to inhibit the transmission of the SARS-CoV-2. Since fomites are one of the vital routes of coronaviral transmission, disinfecting of fomites play a pivotal role in curbing its survival on the contaminated surfaces. Available commercial disinfectants cannot keep the contaminated surfaces sanitized all the time. Self-disinfecting ability of Ag-enriched TiO2 nanocoating due to its superb photocatalytic efficiency can effectively reduce infections caused by spread of pathogens at public places. Anatase Ag-TiO2 nanocoatings synthesized by sol-gel process at 0.5, 1.5, and 2.5% enriching concentrations were casted on glass substrates by spin-coating technique and subsequently annealed at 650 °C. The morphological shape, crystallographic structure, light absorbance, photo-luminosity, vibrational modes, and functional groups of Ag-TiO2 nanocoating on glass surface were studied by FE-SEM, GIXRD, UV-Visible, Photoluminescence, Raman, and FTIR spectroscopy. The developed anatase Ag-TiO2 nanocoatings manifested to improve photocatalytic disinfecting performance due to the achieved small crystallite size of 10.5-19.2 nm, diminished band gap energy of 2.56-2.60 eV, elevated surface area of 0.802-1.470 ×105 cm2/g, and enhanced light absorbance. Among the enriched specimens, 0.5% Ag-TiO2 nanocoatings predicted an overall exalted functionality compared to pristine one.

15.
Am J Med Sci ; 363(6): 526-537, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-34995576

RESUMEN

BACKGROUND: Cervical cancer (CC) is the fourth most common gynecological malignancy globally. This suggests the need for improved markers for prognosis, better understanding of the molecular mechanism, and targets for therapy. The defective exocytosis pathway is proposed as bona fide drivers of carcinogenesis. This study aimed to identify the exocytosis pathway network and its contribution to CC. METHODS: We screened exocytosis genes from the The Cancer Genome Atlas Cervical Squamous Cell Carcinoma and Endocervical Adenocarcinoma (TCGA-CESC) dataset and performed differential expression and methylation, Kaplan-Meier survival, and pathway enrichment analysis. We constructed the protein-protein interaction networks (PPIN), predicted the possible metastatic genes, and identified FDA approved drugs to target the exocytosis network in CC. RESULTS: Integrated bioinformatics analysis identified 245 differentially methylated genes, including 153 hypermethylated and 92 hypomethylated genes. Further, 89 exocytosis pathway genes were differentially expressed, including 60 downregulated and 29 upregulated genes in CC. The overlapping analysis identified 39 genes as methylation regulated genes and showed an inverse correlation between methylation and expression. The HCMDB database identified nine of the identified genes (GRIK5, PTPN6, GAB2, ATP8B4, HTR2A, SPARC, CLEC3B, VWF, and S100A11) were linked with metastasis in CC. Moreover, the Kaplan-Meier survival analysis identified that high expression of PTPN6 and low expression of CLEC3B were significantly linked with poor overall survival (OS) in patients with CC. The KEGG pathway enrichment analysis identified differentially expressed genes that were mainly involved with proteoglycans in cancer, TGF-beta signaling, PI3K-Akt signaling, MAPK signaling pathway, and others. The PPIN identified 89 nodes, 192 edges with VWF, MMP9, THBS1, IGF1, CLU, A2M, IGF2, SPARC, VAMP2, and FIGF as top 10 hub genes. The drug-gene interaction analysis identified 188 FDA approved drugs targeting 32 genes, including 5 drugs that are already in use for treating CC. CONCLUSIONS: In summary, we have identified the exocytosis pathway networks, candidate genes, and novel drugs for better management of CC.


Asunto(s)
Neoplasias del Cuello Uterino , Biomarcadores de Tumor/genética , Exocitosis , Femenino , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Humanos , Fosfatidilinositol 3-Quinasas/genética , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología , Factor de von Willebrand/genética , Factor de von Willebrand/metabolismo
16.
Kathmandu Univ Med J (KUMJ) ; 20(80): 443-447, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-37795721

RESUMEN

Background The median artery (transitory artery) represents the forearm's embryonic arterial axis. At 8th week of gestation retreats into a little canal that supplies the median nerve. Later, ulnar and radial arteries take its place. Adults may still have it in either a palmar or an antebrachial pattern. The persistent median arteries are a long, angular arterial that extends to the hand's palmar surface. The median artery only partially recedes in the antebrachial type. Objective To identify the median artery distribution in the adult Nepalese population. Method Twenty-five adult human cadavers' left and right upper limbs undergone to descriptive research. The persistent median artery was exposed according to the Cunningham's Manual of Practical Anatomy. Result The forearm and hand arteries in each of the fifty upper limbs from the twentyfive formalin-embalmed human cadavers were studied. Among fifty upper limbs, persistent median arteries were found in six (twelve percent) of them. One percent of a cadaver's right and left limbs had bilateral persisting median arteries (ante brachial). Persistent median artery of the ante brachial type that arises from the anterior interosseous artery in a right upper limb. Persistent median artery emerging from the posterior interosseous arteries were visible in one right upper limb. Conclusion The study showed persistent median artery of ante brachial type. The posterior interosseus artery is the source of the majority of antebrachial type. A median artery piercing the median nerve was discovered.


Asunto(s)
Brazo , Antebrazo , Adulto , Humanos , Antebrazo/irrigación sanguínea , Extremidad Superior , Arterias/anatomía & histología , Cadáver
17.
J Ayurveda Integr Med ; 12(4): 579-589, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34674920

RESUMEN

BACKGROUND: Colorectal cancer (CC) is the third most common cancer in the world. Annona reticulata (AR) also known as bullock's heart, is a traditional herb. AR leaf extract was initially investigated for its anti-bacterial, anti-inflammatory, anti-malarial, anti-helminthic, anti-stress, and wound healing properties. Only a few in vitro cancer studies have been conducted on AR. Although few studies have linked AR leaf extract to many cancers, comprehensive studies addressing regulation, biological functions, and molecular mechanisms leading to CC pathogenesis are clearly lacking. OBJECTIVES: The present study aimed to explore the antioxidant and anti-cancer potentials of AR leaf extract in CC. MATERIALS AND METHODS: The MTT assay was used to test the anti-proliferative activity of AR leaf extract in vitro on the HCT116 cell line. Qualitative and quantitative phytochemical characterization was carried out using gas chromatography: mass spectrometry (GC-MS). 1,2-dimethylhydrazine (DMH) was used to establish CC model in female Wistar rats. The acute toxicity of AR leaf extract was tested in accordance with OECD guidelines. Aberrant Crypt Foci (ACF) count, organ index, and hematological estimations were used to screen for in vivo anti-cancer potential. The antioxidant activity of colon homogenate was determined. RESULTS: The alcoholic leaf extract (IC50, 0.55 µg/ml) was found to be more potent than the aqueous extract. Using GC-MS, a total of 108 compounds were quantified in the alcoholic leaf extract. The LD 50 value was found to be safe at a dose of 98.11 mg/kg of body weight. AR alcoholic leaf extract significantly (p < 0.05) decreased ACF count and normalized colon length/weight ratio. AR leaf extract increased RBC, hemoglobin and platelets levels. The AR alcoholic leaf extract reduced the DMH-induced tumors and significantly (p < 0.05) increased the activity of endogenous antioxidant enzymes such as catalase, reduced glutathione, superoxide dismutase, and decreased the lipid peroxidase activity. AR leaf extract reduced the inflammation caused by DMH and helped to repair the colon's damaged muscle layers. CONCLUSION: Based on the findings from the present study, it can be concluded that the alcoholic leaf extract of AR has antioxidant and anti-proliferative properties and can aid in the prevention of CC development and dysplasia caused by DMH.

18.
Braz J Biol ; 83: e247701, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34468529

RESUMEN

Staphylococcus aureus is an important foodborne pathogen associated to food intoxication and other multiple infections in human being. Its presence in salted food is a serious issue due to its salt tolerance potential. A study was conducted to analyze the presence of enterotoxins producing drug resistance S. aureus in salted sea fish from Gwadar. Freshly persevered samples (n=50) of salted fish were subjected to analyze the presence of S. aureus using 16S rRNA and Nuc genes primers. The isolates were then evaluated for drug resistance and enterotoxins producing potential using specific primers for MecA (methicillin resistance gene), (SEA) staphylococcal enterotoxin A and (SEB) staphylococcal enterotoxin B genes. Total 13/50 (26%) of the samples were found positive for the presence of S. aureus, preliminary confirmed with biochemical profiling and finally with the help of target genes presence. The isolates were found showing 100% resistant to methicillin, which were molecularly confirmed by the presence of MecA gene present in genome. The isolates 5/13 (38%) were positive for SEA and 3/13 (23%) for SEB genes, whereas 2/13 (15%) were confirmed having both SEA and SEB genes in its genome. It was also confirmed that all the isolates were capable to form biofilm over the glass surfaces. It was concluded that the study confirmed the presence of enterotoxigenic methicillin resistance Staphylococcus aurous (MRSA) in salted fish product, that poses gross food safety concern. Preventive and control measures are necessary to handle this serious food safety concern.


Asunto(s)
Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Animales , Productos Pesqueros , Humanos , Staphylococcus aureus Resistente a Meticilina/genética , ARN Ribosómico 16S , Staphylococcus aureus/genética
19.
J Genet Eng Biotechnol ; 19(1): 74, 2021 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-33999298

RESUMEN

BACKGROUND: The green synthesis strategy of metallic nanoparticles (NPs) has become popular due to being environmentally friendly. Stable silver nanoparticles (AgNPs) have been synthesized by natural products such as starch, soy protein, various extract of leaves, barks, and roots functioning both as reducing and stabilizing agents. Likewise, silk sericin (SS) is a globular protein discarded in the silk factory might be used for NP synthesis. In this research, we focus on the green synthesis and stabilization of AgNPs by SS as well as assessment of their antibacterial activities against some drug-resistant pathogen. RESULTS: SS was extracted from Bombyx mori silkworm cocoons in an aqueous medium. 17 w/w% of dry sericin powder with respect to the cocoon's weight was obtained by freeze-drying. Furthermore, AgNPs conjugated to sericin, i.e., SS-capped silver nanoparticles (SS-AgNPs) were synthesized by easy, cost-effective, and environment-friendly methods. The synthesized SS-AgNPs were characterized by UV-visible spectroscopy, Fourier-transform infrared-attenuated total reflection (FTIR-ATR) spectroscopy, transmission electron microscopy (TEM), and X-ray diffraction measurement. It has been found from the absorbance of UV-visible spectroscopy that a higher percent of SS-AgNPs was obtained at a higher concentration of silver nitrate solution. FTIR-ATR spectra showed that the carboxylate groups obtained from silk sericin act as a reducing agent for the synthesis of silver nanoparticles, while NH2+ and COO- act as a stabilizer of AgNPs. The X-ray diffractogram of SS-AgNPs was quite different from AgNO3 and sericin due to a change in the crystal structure. The diameter of AgNPs was around 20-70 nm observed using TEM. The synthesized SS-AgNPs exhibited strong antibacterial activity against multidrug-resistant pathogens, Escherichia coli and Pseudomonas aeruginosa. Minimal inhibitory/bactericidal concentrations against E. coli and P. aeruginosa were 20µg/mL. CONCLUSIONS: This study encourages the use of Bombyx mori for the ecofriendly synthesis of SS-AgNPs to control multidrug-resistant microorganisms.

20.
Science ; 371(6531)2021 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-33602829

RESUMEN

Transmembrane ß-barrel proteins (TMBs) are of great interest for single-molecule analytical technologies because they can spontaneously fold and insert into membranes and form stable pores, but the range of pore properties that can be achieved by repurposing natural TMBs is limited. We leverage the power of de novo computational design coupled with a "hypothesis, design, and test" approach to determine TMB design principles, notably, the importance of negative design to slow ß-sheet assembly. We design new eight-stranded TMBs, with no homology to known TMBs, that insert and fold reversibly into synthetic lipid membranes and have nuclear magnetic resonance and x-ray crystal structures very similar to the computational models. These advances should enable the custom design of pores for a wide range of applications.


Asunto(s)
Simulación por Computador , Proteínas de la Membrana/química , Modelos Moleculares , Conformación Proteica en Lámina beta , Ingeniería de Proteínas , Secuencia de Aminoácidos , Cristalografía por Rayos X , Enlace de Hidrógeno , Interacciones Hidrofóbicas e Hidrofílicas , Membrana Dobles de Lípidos , Espectroscopía de Resonancia Magnética , Membranas Artificiales , Micelas , Conformación Proteica , Pliegue de Proteína , Estabilidad Proteica
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