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1.
Sci Rep ; 12(1): 7742, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35546602

RESUMO

Current biomaterials effectively replace biological structures but are limited by infections and long-term material failures. This study examined the molecular mechanisms of radio frequency glow discharge treatments (RFGDT) in mediating the disinfection of biomaterial surfaces and concurrently promoting cell attachment and proliferation. Dental biomaterials were subjected to RFGDT, and viability of oral microbial species, namely Streptococcus mutants (SM), Streptococcus gordonii (SG), Moraxella catarrhalis (MC), and Porphyromonas gingivalis (PG), were assessed. Cell attachment and survival of a pre-odontoblast cell line, MDPC-23, was examined. Finally, mechanistic investigations into redox generation and biological signaling were investigated. Based on their compositions, dental biomaterials induced reactive oxygen species (ROS) following dose-dependent RFGDT. Reduced microbial viability was evident following RFGDT in the catalase-negative (SM and SG) species more prominently than catalase-positive (MC and PG) species. Cell adhesion assays noted improved MDPC-23 attachment and survival. Pretreatments with N-acetylcysteine (NAC) and catalase abrogated these responses. Immunoassays noted redox-induced downstream expression of a laminin receptor, Ribosomal Protein SA, following RFGDT. Thus, RFGDT-induced redox mediates antimicrobial and improves cell responses such as adhesion and proliferation. These observations together provide a mechanistic rationale for the clinical utility of RFGDT with dental biomaterials for regenerative clinical applications.


Assuntos
Laminina , Streptococcus gordonii , Materiais Biocompatíveis/farmacologia , Catalase/farmacologia , Adesão Celular , Laminina/farmacologia , Oxirredução , Porphyromonas gingivalis , Receptores de Laminina , Proteínas Ribossômicas
2.
Artigo em Inglês | MEDLINE | ID: mdl-34886125

RESUMO

Indoor dust can be a major source of heavy metals, nutrients, and bacterial contamination in residential environments and may cause serious health problems. The goal of this research is to characterize chemical and bacterial contaminants of indoor, settled house dust in the Houston Metropolitan region. To achieve this, a total of 31 indoor dust samples were collected, along with household survey data, which were subsequently analyzed for elemental and bacterial concentrations. Microscopic and geospatial analysis was conducted to characterize and map potential hotspots of contamination. Interestingly Cd, Cr, Cu, Pb, and Zn concentrations of all 31 indoor dust samples were significantly enriched and exceeded soil background concentrations. Furthermore, As, Cd, Pb, and Zn concentrations in the dust samples were significantly correlated to the enteric bacterial load concentrations. Human health assessment revealed that cancer risk values via ingestion for Cd, Cr, and Ni were greater than the acceptable range. Of our 31 dust sample isolates, three Gram-negative and 16 Gram-positive pathogenic bacteria were identified, capable of causing a wide range of diseases. Our results demonstrate that both chemical and bacterial characterization of indoor dust coupled with spatial mapping is essential to assess and monitor human and ecological health risks.


Assuntos
Poeira , Metais Pesados , Bactérias , China , Cidades , Poeira/análise , Monitoramento Ambiental , Humanos , Metais Pesados/análise , Medição de Risco , Texas
3.
Sci Total Environ ; 789: 147818, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34058587

RESUMO

Houston watersheds are susceptible to microbial contamination as well as chemical contaminations from bordering industrial facilities. Bacterial loads in various Houston bayous were determined, and pathogenic Gram-negative bacteria were isolated for characterization. Isolates included Klebsiella aerogenes and Klebsiella pneumoniae. To determine whether environmental exposures to lead (Pb), measured in our Houston bayou samples, resulted in bacterial adaptations, we compared growth kinetics, biofilm production, oxidative stress resistance, and eukaryotic co-culture growth of environmentally isolated K. aerogenes and K. pneumoniae to their respective commercially acquired reference strains. Interestingly, the K. aerogenes environmental isolate displayed significantly better growth than the reference strain in the presence of 50 ppb of Pb. Unexpectedly, we did not observe any differences in biofilm production of the aforementioned strains when challenged with a range of Pb (0.5-50 ppb). However, when comparing our K. pneumoniae environmental isolate to its reference strain, there were significantly higher levels of biofilm produced by the environmental isolate when challenged with Pb concentrations of 10 and 50 ppb. When grown in eukaryotic cell co-culture with either BAES 2B lung cells or CCD 841 colon epithelial cells in the presence of 20 ppb Pb, the environmental isolates of K. aerogenes and K. pneumoniae had a significantly higher fold-increase over 6 h than their respective reference strains. Taken together, the environmentally isolated Klebsiella spp. appeared to be more Pb-tolerant than their respective reference strains, a possible environmental adaptation. Such enhanced tolerance can promote environmental persistence and increase the possibility of causing human disease.


Assuntos
Antibacterianos , Klebsiella , Humanos , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Virulência
4.
Biosci Rep ; 37(5)2017 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-28883083

RESUMO

Endometrial fibrosis is the presence of intrauterine adhesions (IUAs) after any uterine surgery or curettage and it results in infertility and recurrent pregnancy loss. We evaluated the role of human mesenchymal stem cells (hMSCs) as a therapeutic agent of endometrial fibrosis. We also compared the effect of MSCs with the effect of estrogen and neupogen either each alone or as a combined therapy with MSCs. This experimental study was performed on 84 albino rats which were divided into seven groups (n=12 rats/group) as follows, group1: normal control rats, group 2: induced fibrosis, group 3: induced fibrosis that received oral estrogen, group 4: induced fibrosis that received hMSCs, group 5: induced fibrosis that received hMSCs and estrogen, group 6: induced fibrosis that received neupogen, and group 7: induced fibrosis that received hMSCs and neupogen. The extent of fibrosis, vascularization, and inflammation were evaluated by; qRT-PCR for interleukin 1 (IL-1), interleukin 6 (IL-6), TNF, vascular endothelial growth factor (VEGF), transforming growth factor-ß (TGF-ß), and RUNX; ELISA for connective tissue growth factor (CTGF); Western blotting for collagen-I; immunohistochemistry examination for VEGF and RUNX-2; and histopathological assessment. In therapeutic groups either by hMSCs alone or combined with estrogen or neupogen; fibrosis and inflammation (IL-1, IL-6, TNF, TGF-ß, RUNX, CTGF, and collagen-I) were significantly decreased but vascularization (VEGF) was significantly increased (P<0.05) compared with induced fibrosis group. The most significant result was obtained in fibrosis that received combined therapy of hMSCs and neupogen (P=0.000). Stem cells and neupogen are a highly effective alternative regenerative agents in endometrial fibrosis.


Assuntos
Endométrio/patologia , Filgrastim/uso terapêutico , Transplante de Células-Tronco Mesenquimais , Regeneração , Doenças Uterinas/terapia , Animais , Biomarcadores/metabolismo , Modelos Animais de Doenças , Endométrio/fisiologia , Estrogênios/administração & dosagem , Estrogênios/uso terapêutico , Feminino , Fibrose , Filgrastim/administração & dosagem , Células-Tronco Mesenquimais/metabolismo , Ratos , Ratos Wistar , Doenças Uterinas/patologia
5.
Saudi J Kidney Dis Transpl ; 27(5): 921-928, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27751999

RESUMO

The chronic dysfunction stands as the most common cause of renal allograft loss. During the nineties of the past century, this condition was referred to as chronic allograft nephropathy (CAN). Since 2005, CAN has been assigned by the eighth Banff schema to four main categories via histopathological and immunohistochemical findings including chronic antibodymediated rejection (CAMR), chronic T-cell-mediated rejection (CTMR), chronic cyclosporine toxicity (CNITOX), and "interstitial fibrosis (IF)/tubular atrophy; not otherwise specified (NOS)" to eliminate the term CAN. We conducted a retrospective study of renal allograft cases with biopsy-proven chronic damage diagnosed at our nephropathology units, between January 2007 and September 2013, to assign them to the defined categories. Differences between groups were tested using one-way analysis of variance. The frequencies of the diagnostic categories were as follow: CNITOX (43.1%), CAMR (27.5%), CTMR (17.6%), and NOS (11.8%). The serum creatinine level, time posttransplant, and global sclerosis frequency were insignificant among the categories. Nine categorized cases showed transplant glomerulopathy; five of them were seen in association with CAMR. There was a positive relationship between the number of interstitial CD8 + T cells and the degree of IF in CTMR cases. Two cases showed combined features of CAMR and CTMR. Protocol renal allograft biopsy starting 3 months after transplantation with proper monitoring and adjustment of the calcineurin inhibitors level may reduce the potential risk of chronic damage in renal allograft.


Assuntos
Rejeição de Enxerto , Doença Crônica , Egito , Humanos , Transplante de Rim , Estudos Retrospectivos , Transplante Homólogo
6.
Head Neck ; 33(8): 1162-9, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21755559

RESUMO

BACKGROUND: Quality of life (QOL) reflects the need to assess the patient's overall sense of well-being. A nonrandomized, prospective longitudinal study was conducted to evaluate QOL in Egyptian patients treated for laryngeal cancer. METHODS: In all, 60 newly diagnosed patients with laryngeal cancer were divided into 3 groups: surgical resection, radiotherapy, and combined therapy. The European Organization for Research and Treatment of Cancer Quality of Life Questionnaires (EORTC-QLQ) were administered to the patients at 4 points: prior to treatment, during active treatment, and at 3 and 6 months after completion of treatment. RESULTS: All pretreatment scales were worse in the combined therapy group. The functional scales reached their lowest levels in all groups during active treatment. Radiotherapy group scales showed persistent slow recovery. There was striking prevalence of the financial difficulties score in all groups. CONCLUSION: QOL measurement provides information to guide clinical decision making in patients treated for laryngeal carcinoma.


Assuntos
Neoplasias Laríngeas/radioterapia , Neoplasias Laríngeas/cirurgia , Laringectomia/métodos , Qualidade de Vida , Adaptação Psicológica , Estudos de Casos e Controles , Terapia Combinada , Fracionamento da Dose de Radiação , Egito , Feminino , Humanos , Neoplasias Laríngeas/mortalidade , Neoplasias Laríngeas/patologia , Laringectomia/mortalidade , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Prognóstico , Medição de Risco , Perfil de Impacto da Doença , Fatores Socioeconômicos , Inquéritos e Questionários , Resultado do Tratamento
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