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1.
EMBO Rep ; 25(2): 902-926, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38177924

RESUMO

Viruses interact with numerous host factors to facilitate viral replication and to dampen antiviral defense mechanisms. We currently have a limited mechanistic understanding of how SARS-CoV-2 binds host factors and the functional role of these interactions. Here, we uncover a novel interaction between the viral NSP3 protein and the fragile X mental retardation proteins (FMRPs: FMR1, FXR1-2). SARS-CoV-2 NSP3 mutant viruses preventing FMRP binding have attenuated replication in vitro and reduced levels of viral antigen in lungs during the early stages of infection. We show that a unique peptide motif in NSP3 binds directly to the two central KH domains of FMRPs and that this interaction is disrupted by the I304N mutation found in a patient with fragile X syndrome. NSP3 binding to FMRPs disrupts their interaction with the stress granule component UBAP2L through direct competition with a peptide motif in UBAP2L to prevent FMRP incorporation into stress granules. Collectively, our results provide novel insight into how SARS-CoV-2 hijacks host cell proteins and provides molecular insight into the possible underlying molecular defects in fragile X syndrome.


Assuntos
COVID-19 , Síndrome do Cromossomo X Frágil , Humanos , Proteína do X Frágil da Deficiência Intelectual/genética , Proteína do X Frágil da Deficiência Intelectual/metabolismo , Síndrome do Cromossomo X Frágil/genética , Síndrome do Cromossomo X Frágil/metabolismo , Peptídeos/metabolismo , Proteínas de Ligação a RNA/genética , SARS-CoV-2
2.
Proc Natl Acad Sci U S A ; 119(32): e2205690119, 2022 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-35881779

RESUMO

The furin cleavage site (FCS), an unusual feature in the SARS-CoV-2 spike protein, has been spotlighted as a factor key to facilitating infection and pathogenesis by increasing spike processing. Similarly, the QTQTN motif directly upstream of the FCS is also an unusual feature for group 2B coronaviruses (CoVs). The QTQTN deletion has consistently been observed in in vitro cultured virus stocks and some clinical isolates. To determine whether the QTQTN motif is critical to SARS-CoV-2 replication and pathogenesis, we generated a mutant deleting the QTQTN motif (ΔQTQTN). Here, we report that the QTQTN deletion attenuates viral replication in respiratory cells in vitro and attenuates disease in vivo. The deletion results in a shortened, more rigid peptide loop that contains the FCS and is less accessible to host proteases, such as TMPRSS2. Thus, the deletion reduced the efficiency of spike processing and attenuates SARS-CoV-2 infection. Importantly, the QTQTN motif also contains residues that are glycosylated, and disruption of its glycosylation also attenuates virus replication in a TMPRSS2-dependent manner. Together, our results reveal that three aspects of the S1/S2 cleavage site-the FCS, loop length, and glycosylation-are required for efficient SARS-CoV-2 replication and pathogenesis.


Assuntos
COVID-19 , Furina , Proteólise , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Motivos de Aminoácidos/genética , Animais , COVID-19/virologia , Chlorocebus aethiops , Furina/química , Humanos , SARS-CoV-2/genética , SARS-CoV-2/fisiologia , Deleção de Sequência , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/genética , Células Vero , Replicação Viral/genética
3.
Rhinology ; 60(5): 335-346, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35726828

RESUMO

BACKGROUND: Nasal endoscopy is increasingly accessible to ENT surgeons. The characteristics of the allergic upper airway are not well recognised. METHODOLOGY: MEDLINE (1946-2021), EMBASE (1974-2021), and the Cochrane Library were searched on 16th November 2021 to identify articles that reported endoscopic findings of patients with documented allergy who had undergone nasal endoscopy. The review followed the Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy. Meta-analysis was performed by pooling sensitivities and specificities using the hierarchical summary receiver operating characteristics model. RESULTS: A total of 4108 articles were identified, of which 15 manuscripts met the inclusion criteria. The included studies involved 4660 patients who had undergone nasal endoscopy. Middle turbinate (diffuse/polypoid) oedema (sensitivity 58.0%, specificity 84.5%), watery secretions (sensitivity 65.7%, specificity 76.5%), inferior turbinate hypertrophy (sensitivity 86.2%, specificity 32.2%), and unspecified turbinate hypertrophy (sensitivity 82.0%, specificity 42.9%) were identified as the features with the highest predictive value of inhalant allergy. CONCLUSIONS: Diffuse or polypoid oedema of the middle turbinate or watery secretions seen on nasal endoscopy can be a useful adjunct in the identification and diagnosis of inhalant allergy. These clinical features should be part of the diagnostic workup for patients that includes a clinical history and surrogate markers of allergic sensitisation from the skin and serum.


Assuntos
Hipersensibilidade , Conchas Nasais , Biomarcadores , Edema , Endoscopia , Humanos , Hipertrofia
4.
J Comput Aided Mol Des ; 35(11): 1081-1093, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34713377

RESUMO

Opioids are potent painkillers, however, their therapeutic use requires close medical monitoring to diminish the risk of severe adverse effects. The G-protein biased agonists of the µ-opioid receptor (MOR) have shown safer therapeutic profiles than non-biased ligands. In this work, we performed extensive all-atom molecular dynamics simulations of two markedly biased ligands and a balanced reference molecule. From those simulations, we identified a protein-ligand interaction fingerprint that characterizes biased ligands. Then, we built and virtually screened a database containing 68,740 ligands with proven or potential GPCR agonistic activity. Exemplary molecules that fulfill the interacting pattern for biased agonism are showcased, illustrating the usefulness of this work for the search of biased MOR ligands and how this contributes to the understanding of MOR biased signaling.


Assuntos
Receptores Opioides mu/agonistas , Algoritmos , Analgésicos Opioides/farmacologia , Proteínas de Ligação ao GTP/metabolismo , Ligantes , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Ligação Proteica , Receptores Opioides mu/metabolismo , Transdução de Sinais/efeitos dos fármacos
5.
J Food Sci Technol ; 58(8): 2896-2905, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34294951

RESUMO

The emulsifying properties of Oxalis tuberosa starch (native and chemically modified) were evaluated in Pickering emulsions based on the emulsification index, emulsion stability over time and emulsion morphology. The best conditions of chemical modification were found by esterification of starch with octenyl succinic anhydride (OSA) at a concentration of 3% and a reaction time of 2 h, achieving a degree of substitution of 0.033 ± 0.001. The results obtained using Fourier-transform infrared spectroscopy, a Rapid Visco Analyzer, and differential scanning calorimetry, indicated that the starch underwent a change in its structure and that the insertion of the OSA groups was achieved. The amphipathic characteristics of OSA starch were evaluated by forming oil-in-water emulsions. Various concentrations of OSA-starch granules (1, 2.5 and 5 wt%) were used. A higher concentration of particles produced a smaller droplet size of emulsions (76.5 ± 0.9 µm) compared to those formed at a lower concentration of 1% (92.5 ± 1.0 µm). Therefore, the starch modified with OSA displayed the necessary characteristics to be adsorbed at the oil-water interface, achieving Pickering emulsion stabilization.

6.
Int J Mol Sci ; 20(8)2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-31010172

RESUMO

West Nile virus (WNV) is an arbovirus with important public health implications globally. This study characterizes a viral isolate, 2004Hou3, in comparison with the NY99 strain from the original WNV outbreak in New York, USA. NextGen sequencing was used to compare the viral isolates genetically, while wild-type C57/BL6 mice were used to compare pathogenicity and viral persistence. Significant differences in survival and clinical presentations were noted, with minor genetic variations between the two strains potentially offering an explanation. One notable difference is that 5 of 35 mice infected with the 2004Hou3 strain developed hind limb flaccid paralysis, suggesting its possible use as a small animal pathogenesis model for this clinical characteristic often observed in human WN neuroinvasive disease patients but not reported in other animal models of infection. Overall, this study suggests that 2004Hou3 is a less pathogenic strain with potential for use in long-term outcome studies using small animal models.


Assuntos
Vírus do Nilo Ocidental/genética , Vírus do Nilo Ocidental/isolamento & purificação , Animais , Líquidos Corporais/virologia , Chlorocebus aethiops , Feminino , Genótipo , Camundongos Endogâmicos C57BL , Fenótipo , Análise de Sequência de DNA , Análise de Sobrevida , Células Vero , Febre do Nilo Ocidental/virologia
7.
Int J Mol Sci ; 20(8)2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-31010160

RESUMO

West Nile virus (WNV), a mosquito-borne arbovirus, remains a major global health concern. In this study, we optimized PCR methods then assessed serially-collected whole blood (WB), urine (UR), saliva, and semen specimens from a large cohort of WNV-positive participants to evaluate the natural history of infection and persistent shedding of WNV RNA. Viral RNA extraction protocols for frozen WB and UR specimens were optimized and validated through spiking experiments to maximize recovery of viral RNA from archived specimens and to assess the degradation of WNV RNA in stored UR specimens. The resultant procedures were used in conjunction with PCR detection to identify WNV-positive specimens and to quantify their viral loads. A total of 59 of 352 WB, 10 of 38 UR, and 2 of 34 saliva specimens tested positive for WNV RNA. Although a single semen specimen was positive 22 days post onset, we could not definitively confirm the presence of WNV RNA in the remaining specimens. WNV RNA-positive UR specimens exhibited profound loss of viral RNA during storage, highlighting the need for optimal preservation pre-storage. This study provides optimized methods for WNV RNA detection among different fluid types and offers alternative options for diagnostic testing during the acute stages of WNV.


Assuntos
Líquidos Corporais/virologia , Reação em Cadeia da Polimerase/métodos , Febre do Nilo Ocidental/virologia , Vírus do Nilo Ocidental/isolamento & purificação , Estudos de Coortes , Humanos , Masculino , RNA Viral/isolamento & purificação , Saliva/virologia , Sêmen/virologia , Febre do Nilo Ocidental/sangue , Febre do Nilo Ocidental/urina
8.
Psychooncology ; 27(3): 847-856, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29136682

RESUMO

OBJECTIVE: Psychosocial interventions are historically underutilized by cancer caregivers, but support programs delivered flexibly over the Internet address multiple barriers to care. We adapted Meaning-Centered Psychotherapy for cancer caregivers, an in-person psychotherapeutic intervention intended to augment caregivers' sense of meaning and purpose and ameliorate burden, for delivery in a self-administered web-based program, the Care for the Cancer Caregiver (CCC) Workshop. The present study evaluated the feasibility, acceptability, and preliminary effects of this program. METHODS: Eighty-four caregivers were randomized to the CCC Workshop or waitlist control arm. Quantitative assessments of meaning, burden, anxiety, depression, benefit finding, and spiritual well-being were conducted preintervention (T1), within 2-weeks postintervention (T2), and 2- to 3-month follow-up (T3). In-depth semistructured interviews were conducted with a subset of participants. RESULTS: Forty-two caregivers were randomized to the CCC Workshop. Attrition was moderate at T2 and T3, with caregiver burden and bereavement as key causes of drop-out. At T2 and T3, some observed mean change scores and effect sizes were consistent with hypothesized trends (eg, meaning in caregiving, benefit finding, and depressive symptomatology), though no pre-post significant differences emerged between groups. However, a longitudinal mixed-effects model found significant differential increases in benefit finding in favor of the CCC arm. CONCLUSIONS: The CCC Workshop was feasible and acceptable. Based on effect sizes reported here, a larger study will likely establish the efficacy of the CCC Workshop, which has the potential to address unmet needs of caregivers who underutilize in-person supportive care services.


Assuntos
Ansiedade/psicologia , Cuidadores/psicologia , Depressão/psicologia , Internet , Neoplasias/enfermagem , Psicoterapia/métodos , Adulto , Ansiedade/terapia , Depressão/terapia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
9.
Microb Pathog ; 112: 259-268, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28970172

RESUMO

Pseudomonas aeruginosa plasmid pUM505 possesses a pathogenicity island that contains the pumAB genes that encode products with sequence similarity to Toxin-Antitoxin (TA) modules. RT-PCR assays on the overlapping regions of the pumAB genes generated a bicistronic messenger RNA, suggesting that they form an operon. When the pumAB genes were cloned into the pJET vector, recombinant plasmid pJET-pumAB was maintained under nonselective conditions in Escherichia coli cells after six daily subcultures, whereas pJET without pumAB genes was lost. These data indicate that pumAB genes confer post-segregational plasmid stability. In addition, overexpression of the PumA protein in the E. coli BL21 strain resulted in a significant growth inhibition, while BL21 co-expressing the PumA and PumB proteins did not show growth inhibition. These results indicate that pumAB genes encode a TA system where the PumB protein counters the toxic effects of the PumA toxin. Furthermore, P. aeruginosa PAO1 transformants with the pumA gene increased Caenorhabditis elegans and mouse mortality rate and improved mouse organ invasion, effects neutralized by the PumB protein. Moreover, purified recombinant His-PumA protein decreased the viability of C. elegans, indicating that the PumA protein could acts as a toxin. These results indicate that PumA has the potential to promoter the PAO1 virulence against C. elegans and mice when is expressed in absence of PumB. This is the first description, to our knowledge, of a plasmid-encoded TA system that confers plasmid stability and encoded a toxin with the possible ability to increase the P. aeruginosa virulence.


Assuntos
Toxinas Bacterianas/genética , Toxinas Bacterianas/toxicidade , Genes Bacterianos/genética , Plasmídeos/genética , Pseudomonas aeruginosa/genética , Sistemas Toxina-Antitoxina/genética , Fatores de Virulência/genética , Animais , Antitoxinas/genética , Proteínas de Bactérias/genética , Sequência de Bases , Caenorhabditis elegans/efeitos dos fármacos , Modelos Animais de Doenças , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Regulação Bacteriana da Expressão Gênica , Vetores Genéticos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Óperon/genética , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/mortalidade , Pseudomonas aeruginosa/patogenicidade , RNA Bacteriano/análise , Proteínas Recombinantes/genética , Análise de Sequência , Virulência/genética
10.
Rhinology ; 55(1): 90-94, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28214914

RESUMO

BACKGROUND: Extra-oral bitter taste receptors have been associated with innate bacterial defence mechanisms. Genetic variation in T2R38 functionality has been shown to be associated with susceptibility to upper respiratory tract infections and chronic rhinosinusitis (CRS). We sought to independently assess the influence of bitter taste receptor genotype on the presence of culturable bacteria in the sinuses. METHODOLOGY: A cross-sectional analysis of patients with CRS undergoing surgery was performed. Middle meatal nasal swabs were sent for microbiological evaluation at the time of the procedure. Mucosal biopsies were taken and sent for bitter taste receptor genotype analysis. Sequencing of 3 polymorphisms in the TAS2R38 gene was performed to identify genotypes as super-tasters (PAV/PAV), non-tasters (AVI/AVI) or heterozygous expression (PAV/AVI). The presence of culturable organisms and common pathogens were compared with bitter taste receptor genotypes. RESULTS: 25 patients (age 52.4 +/- 18.28 years, 51% female) were assessed. Super-tasters comprised 16% of the group, 24% were non-tasters and 48% had heterozygous expression. A cultured pathogen was grown in 48% of patients; 32% gram-positive, 20% gram-negative, 28% grew Staphylococcus aureus and 12% Pseudomonas aeruginosa. A non-taster genotype was predictive of colonised pathogens. Tissue eosinophilia (more than 10 HPF) was seen in 48%. CONCLUSION: Even in a small sample of patients with CRS, non-taster T2R38 genotype appears to predict the presence of culturable bacteria colonising the sinus cavity at the time of surgery for their condition. A genetic link to patients more likely to become infected is likely.


Assuntos
Seios Paranasais/microbiologia , Rinite/microbiologia , Sinusite/microbiologia , Paladar/genética , Adulto , Doença Crônica , Estudos Transversais , Eosinofilia/patologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Seios Paranasais/patologia , Rinite/patologia , Sinusite/patologia
11.
Rhinology ; 55(4): 332-338, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28888024

RESUMO

BACKGROUND: Inferior turbinate procedures are applied to relieve medically refractory nasal obstruction. However, the nature of congestion differs between allergic(AR) and non-allergic rhinitis(NAR). This study compares surgical outcomes between AR and NAR patients. METHODOLOGY: A case-control study of patients undergoing turbinate with or without septoplasty surgery for nasal obstruction was performed. Patient reported outcomes were: nasal obstruction, global nasal function(GNF), and sino-nasal outcome test(SNOT-22) with rhinitis, facial symptom, sleep and psychological sub-scores. Nasal peak inspiratory flow(NPIF) assessed nasal airflow. Measurements were obtained preoperatively and 3 months postoperatively. RESULTS: 190 patients were assessed. AR had worse obstruction and worse GNF. All outcomes improved post-surgery; nasal obstruction, GNF, SNOT-22, rhinitis-symptoms, facial-symptoms, sleep-function, psychological-function and NPIF. GNF improvement was greater in AR. NPIF improvement was similar between groups. CONCLUSIONS: Both AR and NAR patients gained benefit from surgery to relieve nasal obstruction. AR patients demonstrate greater improvement in GNF score but allergy management may contribute to this.


Assuntos
Obstrução Nasal/cirurgia , Medidas de Resultados Relatados pelo Paciente , Rinite Alérgica/cirurgia , Rinite/cirurgia , Conchas Nasais/cirurgia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obstrução Nasal/etiologia , Septo Nasal/cirurgia , Rinite/complicações , Rinite Alérgica/complicações , Adulto Jovem
12.
Antonie Van Leeuwenhoek ; 109(3): 389-96, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26739475

RESUMO

The pUM505 plasmid was isolated from a clinical strain of Pseudomonas aeruginosa. This plasmid contains a genomic island with sequence similar to islands found in chromosomes of virulent P. aeruginosa clinical isolates. The objective of this work was to determine whether pUM505 increases the virulence of P. aeruginosa and to identify the genes responsible for this property. First, using the lettuce-leaf model, we found that pUM505 significantly increases the virulence of P. aeruginosa reference strain PAO1. pUM505 also increased the PAO1 virulence in a murine model and increased cytotoxicity of this strain toward HeLa cells. Thus, we generated a pUM505 gene library of 103 clones in the pUCP20 binary vector. The library was transferred to Escherichia coli TOP10 and P. aeruginosa PAO1 to identify genes. The lettuce-leaf model allowed us to identify three recombinant plasmids that increased the virulence of both E. coli and P. aeruginosa strains. These recombinant plasmids also increased the virulence of the PAO1 strain in mice and induced a cytotoxic effect in HeLa cells. Eleven genes were identified in the virulent transformants. Of these genes, only the pUM505 ORF 2 has homology with a gene previously implicated in virulence. These results indicate that pUM505 contains several genes that encode virulence factors, suggesting that the plasmid may contribute directly to bacterial virulence.


Assuntos
Genes Bacterianos , Plasmídeos/genética , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/patogenicidade , Animais , Linhagem Celular , Sobrevivência Celular , Modelos Animais de Doenças , Biblioteca Gênica , Humanos , Lactuca/microbiologia , Masculino , Camundongos , Doenças das Plantas/microbiologia , Folhas de Planta/microbiologia , Infecções por Pseudomonas/microbiologia , Infecções por Pseudomonas/mortalidade , Virulência/genética
13.
Cell Rep ; 43(3): 113965, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38492217

RESUMO

G3BP1/2 are paralogous proteins that promote stress granule formation in response to cellular stresses, including viral infection. The nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) inhibits stress granule assembly and interacts with G3BP1/2 via an ITFG motif, including residue F17, in the N protein. Prior studies examining the impact of the G3PB1-N interaction on SARS-CoV-2 replication have produced inconsistent findings, and the role of this interaction in pathogenesis is unknown. Here, we use structural and biochemical analyses to define the residues required for G3BP1-N interaction and structure-guided mutagenesis to selectively disrupt this interaction. We find that N-F17A mutation causes highly specific loss of interaction with G3BP1/2. SARS-CoV-2 N-F17A fails to inhibit stress granule assembly in cells, has decreased viral replication, and causes decreased pathology in vivo. Further mechanistic studies indicate that the N-F17-mediated G3BP1-N interaction promotes infection by limiting sequestration of viral genomic RNA (gRNA) into stress granules.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , DNA Helicases/metabolismo , RNA Helicases/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Virulência , RNA Guia de Sistemas CRISPR-Cas , Proteínas do Nucleocapsídeo , Replicação Viral , RNA Viral/genética
14.
bioRxiv ; 2023 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-37131784

RESUMO

SARS-CoV-2 Omicron variants emerged in 2022 with >30 novel amino acid mutations in the spike protein alone. While most studies focus on receptor binding domain changes, mutations in the C-terminus of S1 (CTS1), adjacent to the furin cleavage site, have largely been ignored. In this study, we examined three Omicron mutations in CTS1: H655Y, N679K, and P681H. Generating a SARS-CoV-2 triple mutant (YKH), we found that the mutant increased spike processing, consistent with prior reports for H655Y and P681H individually. Next, we generated a single N679K mutant, finding reduced viral replication in vitro and less disease in vivo. Mechanistically, the N679K mutant had reduced spike protein in purified virions compared to wild-type; spike protein decreases were further exacerbated in infected cell lysates. Importantly, exogenous spike expression also revealed that N679K reduced overall spike protein yield independent of infection. Although a loss-of-function mutation, transmission competition demonstrated that N679K had a replication advantage in the upper airway over wild-type SARS-CoV-2 in hamsters, potentially impacting transmissibility. Together, the data show that N679K reduces overall spike protein levels during Omicron infection, which has important implications for infection, immunity, and transmission.

15.
J Water Health ; 10(3): 371-9, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22960481

RESUMO

An experimental study of ATCC (American Type Culture Collection) 8739 Escherichia coli bacteria inactivation in water by means of pulsed dielectric barrier discharge (PDBD) atmospheric pressure plasmas is presented. Plasma is generated by an adjustable power source capable of supplying high voltage 25 kV pulses, ∼30 µs long and at a 500 Hz frequency. The process was conducted in a ∼152 cm(3) cylindrical stainless steel coaxial reactor, endowed with a straight central electrode and a gas inlet. The bacterial concentration in water was varied from 10(3) up to 10(8) E. coli cells per millilitre. The inactivation was achieved without gas flow in the order of 82% at 10(8) colony-forming units per millilitre (CFU mL(-1)) concentrations in 600 s. In addition, oxygen was added to the gas supply in order to increase the ozone content in the process, raising the inactivation percentage to the order of 90% in the same treatment time. In order to reach a higher efficiency however, oxygen injection modulation is applied, leading to inactivation percentages above 99.99%. These results are similarly valid for lower bacterial concentrations.


Assuntos
Eletricidade , Escherichia coli/fisiologia , Microbiologia da Água , Purificação da Água/instrumentação , Purificação da Água/métodos
16.
bioRxiv ; 2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36203546

RESUMO

Understanding the molecular basis of innate immune evasion by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an important consideration for designing the next wave of therapeutics. Here, we investigate the role of the nonstructural protein 16 (NSP16) of SARS-CoV-2 in infection and pathogenesis. NSP16, a ribonucleoside 2'- O methyltransferase (MTase), catalyzes the transfer of a methyl group to mRNA as part of the capping process. Based on observations with other CoVs, we hypothesized that NSP16 2'- O MTase function protects SARS-CoV-2 from cap-sensing host restriction. Therefore, we engineered SARS-CoV-2 with a mutation that disrupts a conserved residue in the active site of NSP16. We subsequently show that this mutant is attenuated both in vitro and in vivo , using a hamster model of SARS-CoV-2 infection. Mechanistically, we confirm that the NSP16 mutant is more sensitive to type I interferon (IFN-I) in vitro . Furthermore, silencing IFIT1 or IFIT3, IFN-stimulated genes that sense a lack of 2'- O methylation, partially restores fitness to the NSP16 mutant. Finally, we demonstrate that sinefungin, a methyltransferase inhibitor that binds the catalytic site of NSP16, sensitizes wild-type SARS-CoV-2 to IFN-I treatment. Overall, our findings highlight the importance of SARS-CoV-2 NSP16 in evading host innate immunity and suggest a possible target for future antiviral therapies. Importance: Similar to other coronaviruses, disruption of SARS-CoV-2 NSP16 function attenuates viral replication in a type I interferon-dependent manner. In vivo , our results show reduced disease and viral replication at late times in the hamster lung, but an earlier titer deficit for the NSP16 mutant (dNSP16) in the upper airway. In addition, our results confirm a role for IFIT1, but also demonstrate the necessity of IFIT3 in mediating dNSP16 attenuation. Finally, we show that targeting NSP16 activity with a 2'- O methyltransferase inhibitor in combination with type I interferon offers a novel avenue for antiviral development.

17.
Bioelectrochemistry ; 141: 107879, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34217098

RESUMO

This work presents the study of the voltage and oxygen effect on bacterial inactivation in water using a pulsed dielectric barrier discharge (DBD) under atmospheric pressure, where Escherichia coli (E. coli) and Salmonella typhi (S. typhi) bacteria were used as model microorganisms. A cylindrical DBD reactor was developed and tested in applications to assay the efficiency of bacterial inactivation in water on a volume of 500 mL flowing continuously throughout the system assisted with a peristaltic pump at 4.4 ± 0.1 mL/s. The efficiency of the treatment reached a 6-log10 reduction for both E. coli and S. typhi bacteria at 106 CFU/mL of concentration at the end of the first cycle of treatment at a minimum voltage of 12 kV with oxygen bubbling gas, concluding that there was a minimum voltage to produce inactivation of E. coli and S. typhi samples. Bacterial inactivation without the oxygen condition contrasted with the high rate of inactivation with oxygen at relatively low voltage discharges.


Assuntos
Eletricidade , Escherichia coli , Viabilidade Microbiana , Oxigênio/metabolismo , Salmonella typhi
18.
Breast J ; 16(1): 73-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-19825000

RESUMO

Fibroadenomas are non-cancerous breast tumors commonly seen in teenagers but also found in women at the time of first mammogram. They have distinct physical findings and imaging features but the definitive diagnosis is made by ultrasound or stereotactic guided needle biopsy. Treatment options are observation or surgical removal. Recently, removal by ultrasound-guided technique has been reported. Alternatively, the tumor may be ablated within the breast by cold (cryotherapy) or by heat (laser, radiofrequency, focused ultrasound and microwave). In this paper the laser treatment in two patients, one with bilateral fibroadenomas, with 6 and 8 year follow-up is presented.


Assuntos
Neoplasias da Mama/cirurgia , Fibroadenoma/cirurgia , Terapia a Laser/métodos , Adulto , Biópsia por Agulha , Neoplasias da Mama/patologia , Feminino , Fibroadenoma/patologia , Seguimentos , Humanos , Imuno-Histoquímica , Mamografia/métodos , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Medição de Risco , Fatores de Tempo , Resultado do Tratamento
19.
ACS Chem Neurosci ; 11(23): 3979-3992, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33164503

RESUMO

Salvinorin A is the main bioactive compound in Salvia divinorum, an endemic plant with ancestral use by the inhabitants of the Mazateca mountain range (Sierra Mazateca) in Oaxaca, México. The main use of la pastora, as locally known, is in spiritual rites due to its extraordinary hallucinogenic effects. Being the first known nonalkaloidal opioid-mediated psychotropic molecule, salvinorin A set new research areas in neuroscience. The absence of a protonated amine group, common to all previously known opioids, results in a fast metabolism with the concomitant fast elimination and swift loss of activity. The worldwide spread and psychotropic effects of salvinorin A account for its misuse and classification as a drug of abuse. Consequently, salvinorin A and Salvia divinorum are now banned in many countries. Several synthetic efforts have been focused on the improvement of physicochemical and biological properties of salvinorin A: from total synthesis to hundreds of analogues. In this Review, we discuss the impact of salvinorin A in chemistry and neuroscience covering the historical relevance, isolation from natural sources, synthetic efforts, and pharmacological and safety profiles. Altogether, the chemistry behind and the taboo that encloses salvinorin A makes it one of the most exquisite naturally occurring drugs.

20.
Int J Hyperthermia ; 25(1): 47-55, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19219700

RESUMO

BACKGROUND: Partial breast irradiation post-lumpectomy, with a balloon bearing a radioactive source in its center, is practiced as an alternative to whole breast irradiation in the treatment of breast cancer. The goal is to ablate residual malignant cells within 1 cm radius of the resected lumpectomy margin. We hypothesize that this goal may be achieved with a fluid-filled heated balloon. METHODS: Nubian-cross goats were treated under general anesthesia. The two mammary glands were sequentially bisected and a non-inflated balloon with a heating element was placed in the center of the gland which was re-sutured. Two series of experiments were conducted. In the first 22 goats (44 glands), the balloon was inflated with 5% dextrose to a pressure of 150 mmHg and heated at 87 degrees C over selected time intervals of 1-24 minutes. In the second series (16 glands), the re-programmed device operated at 50-80 mmHg over selected time intervals of 5-20 minutes. The depth of necrosis was histologically determined after sacrificing the goats and excising the glands. RESULTS: In the first series, glandular necrosis was noted to extend to a depth of 3.2-9.6 mm for the above heating cycles. Corresponding figures for the second series ranged from 4.7-8.6 mm for treatment times of one minute 'warm up' to 20 minutes of heating at 90 degrees C. The animals exhibited no systemic side effects post-treatment. CONCLUSION: An experimental model describing a thermal technique causing necrosis of the goat mammary gland is described.


Assuntos
Neoplasias da Mama/cirurgia , Cabras/cirurgia , Hipertermia Induzida/métodos , Glândulas Mamárias Animais , Animais , Neoplasias da Mama/patologia , Cateterismo/métodos , Feminino , Humanos , Glândulas Mamárias Animais/patologia , Glândulas Mamárias Animais/cirurgia , Mastectomia Segmentar/métodos , Necrose/patologia
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