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1.
Appl Environ Microbiol ; 90(6): e0032524, 2024 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-38752748

RESUMEN

Saccharomyces boulardii has been a subject of growing interest due to its potential as a probiotic microorganism with applications in gastrointestinal health, but the molecular cause for its probiotic potency has remained elusive. The recent discovery that S. boulardii contains unique mutations causing high acetic acid accumulation and inhibition of bacterial growth provides a possible clue. The natural S. boulardii isolates Sb.P and Sb.A are homozygous for the recessive mutation whi2S270* and accumulate unusually high amounts of acetic acid, which strongly inhibit bacterial growth. However, the homozygous whi2S270* mutation also leads to acetic acid sensitivity and acid sensitivity in general. In the present study, we have constructed a new S. boulardii strain, derived from the widely therapeutically used CMCN I-745 strain (isolated from the pharmaceutical product Enterol), producing even higher levels of acetic acid while keeping the same tolerance toward low pH as the parent Enterol (ENT) strain. This newly engineered strain, named ENT3, has a homozygous deletion of ACH1 and strong overexpression of ALD4. It is also able to accumulate much higher acetic acid concentrations when growing on low glucose levels, in contrast to the ENT wild-type and Sb.P strains. Moreover, we show the antimicrobial capacity of ENT3 against gut pathogens in vitro and observed that higher acetic acid production might correlate with better persistence in the gut in healthy mice. These findings underscore the possible role of the unique acetic acid production and its potential for improvement of the probiotic action of S. boulardii.IMPORTANCESuperior variants of the probiotic yeast Saccharomyces boulardii produce high levels of acetic acid, which inhibit the growth of bacterial pathogens. However, these strains also show increased acid sensitivity, which can compromise the viability of the cells during their passage through the stomach. In this work, we have developed by genetic engineering a variant of Saccharomyces boulardii that produces even higher levels of acetic acid and does not show enhanced acid sensitivity. We also show that the S. boulardii yeasts with higher acetic acid production persist longer in the gut, in agreement with a previous work indicating competition between probiotic yeast and bacteria for residence in the gut.


Asunto(s)
Ácido Acético , Probióticos , Saccharomyces boulardii , Ácido Acético/metabolismo , Saccharomyces boulardii/genética , Animales , Ratones
2.
Int J Mol Sci ; 25(5)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38474115

RESUMEN

Regulatory T lymphocytes play a critical role in immune regulation and are involved in the aberrant cell elimination by facilitating tumor necrosis factor connection to the TNFR2 receptor, encoded by the TNFRSF1B polymorphic gene. We aimed to examine the effects of single nucleotide variants TNFRSF1B c.587T>G, c.*188A>G, c.*215C>T, and c.*922C>T on the clinicopathological characteristics and survival of cutaneous melanoma (CM) patients. Patients were genotyped using RT-PCR. TNFRSF1B levels were measured using qPCR. Luciferase reporter assay evaluated the interaction of miR-96 and miR-1271 with the 3'-UTR of TNFRSF1B. The c.587TT genotype was more common in patients younger than 54 years old than in older patients. Patients with c.*922CT or TT, c.587TG or GG + c.*922CT or TT genotypes, as well as those with the haplotype TATT, presented a higher risk of tumor progression and death due to the disease effects. Individuals with the c.*922TT genotype had a higher TNFRSF1B expression than those with the CC genotype. miR-1271 had less efficient binding with the 3'-UTR of the T allele when compared with the C allele of the SNV c.*922C>T. Our findings, for the first time, demonstrate that TNFRSF1B c.587T>G and c.*922C>T variants can serve as independent prognostic factors in CM patients.


Asunto(s)
Melanoma , MicroARNs , Neoplasias Cutáneas , Humanos , Anciano , Persona de Mediana Edad , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Genotipo , MicroARNs/genética , Receptores Tipo II del Factor de Necrosis Tumoral/genética
3.
Biomacromolecules ; 23(4): 1545-1556, 2022 04 11.
Artículo en Inglés | MEDLINE | ID: mdl-34890507

RESUMEN

Localized release of nucleic acid therapeutics is essential for many biomedical applications, including gene therapy, tissue engineering, and medical implant coatings. We applied the substrate-mediated transfection and layer-by-layer (LbL) technique to achieve an efficient local gene delivery. In the experiments presented herein, we embeded lipoplexes containing plasmid DNA encoding for enhanced green fluorescent protein (pEGFP) within polyelectrolyte alginate-based microgels composed of poly(allylamine hydrochloride) (PAH), chondroitin sulfate (CS), and poly-l-lysine (PLL) with diameters between 70 and 90 µm. Droplet-based microfluidics was used as the main process to produce the alginate (ALG)-based microgels with discrete size, shape, and low coefficient of variation. The physicochemical and morphological properties of the polyelectrolyte microgels were characterized via optical microscopy, scanning electron microscopy (SEM), and zeta potential analysis. We found that polyelectrolyte microgels provide low cytotoxicity and cell-material interactions (adhesion, spreading, and proliferation). In addition, the microsystem showed the ability to load lipoplexes and a loading efficiency equal to 83%, and it enabled in vitro surface-based transfection of MCF-7 cells. This approach provides a new suitable route for cell adhesion and local gene delivery.


Asunto(s)
Microgeles , Alginatos/química , Biomimética , Técnicas de Cultivo Tridimensional de Células , Terapia Genética , Polielectrolitos
4.
Biopolymers ; 112(7): e23432, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33982812

RESUMEN

Efficient delivery of nanometric vectors complexed with nanoparticles at a target tissue without spreading to other tissues is one of the main challenges in gene therapy. One means to overcome this problem is to confine such vectors within microgels that can be placed in a target tissue to be released slowly and locally. Herein, a conventional optical microscope coupled to a common smartphone was employed to monitor the microfluidic production of monodisperse alginate microgels containing nanoparticles as a model for the encapsulation of vectors. Alginate microgels (1.2%) exhibited an average diameter of 125 ± 3 µm, which decreased to 106 ± 5 µm after encapsulating 30 nm fluorescent nanoparticles. The encapsulation efficiency was 70.9 ± 18.9%. In a 0.1 M NaCl solution, 55 ± 5% and 92 ± 4.7% of nanoparticles were released in 30 minutes and 48 hours, respectively. Microgel topography assessment by atomic force microscopy revealed that incorporation of nanoparticles into the alginate matrix changes the scaffold's interfacial morphology and induces crystallization with the appearance of oriented domains. The high encapsulation rate of nanoparticles, alongside their continuous release of nanoparticles over time, makes these microgels and the production unit a valuable system for vector encapsulation for gene therapy research.


Asunto(s)
Alginatos/química , Microfluídica/métodos , Microgeles/química , Nanopartículas/química , Unión Competitiva , Ligandos , Microscopía de Fuerza Atómica , Nanopartículas/metabolismo , Tamaño de la Partícula
5.
J Cutan Pathol ; 48(7): 863-869, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33486806

RESUMEN

BACKGROUND: Pyogenic granuloma (PG) is a lesion characterized by the proliferation of blood vessels, commonly affecting the skin and the mouth. We aimed to compare clinical, microscopic, and immunohistochemical features of the two types of oral PG: lobular capillary hemangioma (LCH) and non-LCH (NLCH). METHODS: Epidemiological and clinical data from 2000 to 2018 were collected from the archives of our institution, and histopathological sections of PG were reviewed. Immunohistochemical analyses (CD34, D2-40, SMA, mast cell, and Ki-67) were performed in 34 cases. RESULTS: Sixty-two LCH and 107 non-LCH samples were included. The mean (±SD) age of the patients was 38.59 ± 16.96 years; 55.62% were female; 39.64% of cases occurred in the gingiva, 44% of the nodules were pedunculated, and 13.02% of patients reported a history of trauma. NLCH was more prevalent among older patients than LCH. The most prevalent site of LCH was the lips, while NLCH occurred more in the gingiva (P < 0.05). Epithelial atrophy, microvessels, SMA-positive areas, and Ki-67-positive nuclei were more prevalent in LCH (P < 0.05). CONCLUSIONS: PG accounted for 2.25% of lesions archived in the pathology service and most cases were NLCH. LCH and NLCH exhibited clinicopathological differences in terms of age, site, epithelial atrophy, vascularization, and proliferation rate.


Asunto(s)
Granuloma Piogénico/diagnóstico , Granuloma Piogénico/metabolismo , Mucosa Bucal/patología , Neovascularización Patológica/patología , Actinas/metabolismo , Adulto , Biopsia , Estudios de Casos y Controles , Femenino , Encía/patología , Granuloma Piogénico/epidemiología , Granuloma Piogénico/patología , Humanos , Inmunohistoquímica/métodos , Antígeno Ki-67/metabolismo , Labio/patología , Masculino , Persona de Mediana Edad , Boca/patología , Mucosa Bucal/irrigación sanguínea , Mucosa Bucal/ultraestructura , Prevalencia , Estudios Retrospectivos
6.
J Allergy Clin Immunol ; 146(5): 1137-1151, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32199911

RESUMEN

BACKGROUND: Scavenger receptor CD163 is exclusively expressed on monocytes/macrophages and is widely used as a marker for alternatively activated macrophages. However, the role of CD163 is not yet clear. OBJECTIVES: We sought to examine the function of CD163 in steady-state as well as in sterile and infectious inflammation. METHODS: Expression of CD163 was analyzed under normal and inflammatory conditions in mice. Functional relevance of CD163 was investigated in models of inflammation in wild-type and CD163-/- mice. RESULTS: We describe a subpopulation of bone marrow-resident macrophages (BMRMs) characterized by a high expression of CD163 and functionally distinct from classical bone marrow-derived macrophages. Development of CD163+ BMRMs is strictly dependent on IFN regulatory factor-8. CD163+ BMRMs show a specific transcriptome and cytokine secretion pattern demonstrating a specific immunomodulatory profile of these cells. Accordingly, CD163-/- mice show a stronger inflammation in allergic contact dermatitis, indicating a regulatory role of CD163. However, CD163-/- mice are highly susceptible to S aureus infections, demonstrating the relevance of CD163 for antimicrobial defense as well. CONCLUSIONS: Our data indicate that anti-inflammatory and immunosuppressive mechanisms are not necessarily associated with a decreased antimicrobial activity. In contrast, our data define a novel macrophage population that controls overwhelming inflammation on one hand but is also necessary for an effective control of infections on the other hand.


Asunto(s)
Antígenos CD/metabolismo , Antígenos de Diferenciación Mielomonocítica/metabolismo , Células de la Médula Ósea/metabolismo , Dermatitis Alérgica por Contacto/inmunología , Inflamación/inmunología , Macrófagos/metabolismo , Receptores de Superficie Celular/metabolismo , Infecciones Estafilocócicas/inmunología , Staphylococcus aureus/fisiología , Animales , Antígenos CD/genética , Antígenos de Diferenciación Mielomonocítica/genética , Células de la Médula Ósea/inmunología , Células Cultivadas , Citocinas/metabolismo , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Humanos , Inmunomodulación , Factores Reguladores del Interferón/genética , Factores Reguladores del Interferón/metabolismo , Activación de Macrófagos , Macrófagos/inmunología , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Noqueados , Receptores de Superficie Celular/genética , Transcriptoma
7.
J Prosthodont ; 30(7): 581-589, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33325079

RESUMEN

PURPOSE: To assess the degree of satisfaction and quality of life of patients with removable prostheses using the Geriatric Oral Health Assessment Index (GOHAI) and Oral Health Impact Profile in Edentulous Adults (OHIP-EDENT), in addition to evaluating the questionnaires for their validation. MATERIALS AND METHODS: Eighty patients participated in the study after completing prosthetic rehabilitation treatment. Patients were evaluated using the OHIP-EDENT and GOHAI questionnaires to assess the criteria for quality of life, esthetics, phonetics, masticatory function, stability, comfort, and alteration of taste and pain related to the completed prostheses. The results were subjected to the chi-squared test, Fisher's exact test, and a multinomial logistic regression model, with a significance level of 5%. RESULTS: The most commonly used removable prosthesis was mandibular removable partial denture (RPD) (n = 43, 53.8%), followed by maxillary RPD (n = 42, 52.5%), maxillary complete denture (CD) (n = 33, 41.3%), and mandibular CD (n = 31, 38.8%). Most patients had to have one (n = 29, 36.3%), two (n = 21, 26.3%), or none (n = 18, 23.8%) adjustments in their prostheses. Five (6.3%) patients' prostheses required three adjustments, and six (7.5%) required four or more adjustments. All reported improvement in esthetics after using the prostheses (p < 0.05). The validation of the questionnaire proved to be more viable when completed without the presence of specific domains. CONCLUSION: The results of this study indicated that removable prostheses improved the quality of life of rehabilitated patients. The questionnaires used need to be answered and evaluated in their entirety for validation.


Asunto(s)
Salud Bucal , Calidad de Vida , Adulto , Anciano , Dentadura Completa , Estética Dental , Humanos , Satisfacción del Paciente , Encuestas y Cuestionarios
8.
J Contemp Dent Pract ; 22(5): 491-500, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34318766

RESUMEN

AIM AND OBJECTIVE: This study evaluated the repercussions of coronavirus disease-2019 (COVID-19) in Brazilian dentists' personal and professional routines. MATERIALS AND METHODS: Brazilian dentists were invited to participate in an online survey with questions pertaining to COVID-19 and its repercussions in dental practice. Sample calculation was performed using the Survey Monkey software (www.surveymonkey.com). The minimum sample required to obtain a 95% confidence level (CI) and 1% margin of error was 4,214. The eligibility criteria were dental professionals, of any gender and age, who were working in dentistry in a public, private, or university environment, regardless of the time of experience in the profession, and agreed to participate in the study. The survey was structured such that all the Brazilian regions were touched upon, thereby aiming at covering and collecting the representative data of the region. Responses were analyzed using chi-square tests, t-tests, and one-way analysis of variance, with statistical significance at p <0.05. RESULTS: A total of 15,813 dentists responded to the survey, representing all Brazilian regions. Complete social isolation was practiced by 96.21% of the respondents, and approximately 25% knew someone who had contracted COVID-19. Public health specialists were the most likely to provide emergency treatment (71.90%, p <0.001). In the Northeast region, 79.80% of respondents agreed that conventional personal protective equipment (PPE) was insufficient to prevent COVID-19 transmission, and 79.10% considered their biosecurity measures insufficient (p <0.001). In the North region, most dentists continued to perform elective dental procedures (p <0.001). CONCLUSION: It is possible to conclude that Brazilian dentists demonstrated high knowledge of COVID-19's main symptoms and the risks of transmission through dental procedures. Most respondents practiced social isolation, although some did continue to provide emergency dental care. CLINICAL SIGNIFICANCE: To improve infection control in dental care settings against COVID-19, it is necessary to educate and raise awareness among professionals. How to cite this article: Candeiro GTM, Neri JR, Carvalho BMDF, et al. Repercussions of COVID-19 in Brazilian Dentists' Personal and Professional Routines: An Online Survey. J Contemp Dent Pract 2021;22(5):491-500.


Asunto(s)
COVID-19 , Brasil , Odontólogos , Humanos , SARS-CoV-2 , Encuestas y Cuestionarios
9.
Oncologist ; 25(12): e1956-e1967, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32762143

RESUMEN

BACKGROUND: Adjuvant chemotherapy with 5-fluorouracil (5-FU) and oxaliplatin increases recurrence-free and overall survival in patients with colon adenocarcinoma. It is known that these drugs have been associated with cardio- and neurotoxicity. We investigated the effects of 5-FU ± oxaliplatin on cardiac function, vascular responses, neurovascular control, and physical capacity in patients with colon cancer. METHODS: Twenty-nine patients with prior colectomy for stage II-III adenocarcinoma and clinical indication for adjuvant chemotherapy were allocated to receive 5-FU (n = 12) or 5-FU + oxaliplatin (n = 17), according to the oncologist's decision. All the analyses were performed just before and after the end of chemotherapy. Cardiac function was assessed by echocardiography and speckle tracking, and cardiac autonomic control was assessed by heart rate variability (HRV). Vascular endothelial function was assessed by flow-mediated dilation (FMD). Muscle sympathetic nerve activity (MSNA) was directly recorded by microneurography technique, and muscle blood flow by venous occlusion plethysmography. Physical capacity was evaluated by cardiopulmonary exercise test. RESULTS: Chemotherapy (pooled data) did not significantly change left ventricular ejection fraction (58 ± 1 vs. 55 ± 2%, p = .14), longitudinal strain (-18 ± 1 vs. -18 ± 1%, p = .66), and HRV. Likewise, chemotherapy did not significantly change FMD, muscle blood flow, and MSNA (33 ± 2 vs. 32 ± 1 bursts/min, p = .31). Physical capacity was not significantly changed in both groups. Similar findings were observed when the patients were subdivided in 5-FU and 5-FU + oxaliplatin treatment groups. 5-FU and 5-FU + oxaliplatin did not significantly change cardiac function, HRV, vascular responses, MSNA, and physical capacity. CONCLUSION: This study provides evidence that adjuvant treatment with 5-FU ± oxaliplatin is well tolerated and does not promote changes compatible with long-term cardiotoxicity. IMPLICATIONS FOR PRACTICE: Adjuvant chemotherapy with 5-fluorouracil (5-FU) and oxaliplatin increases recurrence-free and overall survival in patients with colon adenocarcinoma; however, these drugs have been associated with cardio- and neurotoxicity. This study investigated the effects of these drugs on cardiac function, vascular responses, neurovascular control, and physical capacity in patients with colon cancer. It was found that 5-FU and oxaliplatin did not significantly change cardiac function, cardiac autonomic control, vascular endothelial function, muscle sympathetic nerve activity, and physical capacity. This study provides evidence that adjuvant treatment with 5-FU ± oxaliplatin is well tolerated and does not promote changes compatible with long-term cardiotoxicity.


Asunto(s)
Neoplasias del Colon , Fluorouracilo , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Quimioterapia Adyuvante , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/patología , Fluorouracilo/uso terapéutico , Humanos , Leucovorina/uso terapéutico , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Compuestos Organoplatinos/uso terapéutico , Oxaliplatino/uso terapéutico , Volumen Sistólico , Función Ventricular Izquierda
10.
J Oral Pathol Med ; 49(10): 1078-1083, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32816327

RESUMEN

BACKGROUND: Abnormalities in the intrinsic apoptosis pathway, associated with single nucleotide variants (SNVs) in caspase (CASP) genes, alter head and neck squamous cell carcinoma (HNSCC) proliferation and progression. This prospective study aimed to evaluate whether CASP9 c.-1339A>G and CASP3 c.-1191A>G SNVs influence the outcome of patients with HNSCC. Two hundred sixty-two HNSCC patients were enrolled in the study. METHODS: DNA and RNA of peripheral blood samples were analyzed using real-time polymerase chain reaction (PCR) for genotyping and quantitative PCR method for gene expression, respectively. Differences in CASP3 expressions were analyzed using the Mann-Whitney test. Event-free survival (EFS) and overall survival (OS) were calculated using the Kaplan-Meier curves, log-rank test, and Cox analyses. RESULTS: CASP3 c.-1191AG or GG genotype was associated with higher CASP3 expression when compared with AA genotype (0.50 arbitrary units (AUs) ± 0.29 standard deviation (SD) vs 0.28 AUs ± 0.12 SD; P = .02). Patients with CASP9 c.-1339GG genotype had 1.54 more chance of presenting disease progression or relapse than patients with CASP9 c.-1339AA or AG genotype. Patients with CASP9 c.-1339GG and CASP3 c.-1191GG combined genotype had 2.64 more chance of presenting progression or relapse of the disease and 2.84 more chance of evolving to death than those with the remaining combined genotypes. CONCLUSIONS: Our findings provide, for the first time, preliminary evidence that inherited abnormalities in the intrinsic apoptosis pathway, related to CASP9 c.-1339A>G and CASP3 c.-1191A>G SNVs, act as predictors of HNSCC patients' survival.


Asunto(s)
Neoplasias de Cabeza y Cuello , Polimorfismo de Nucleótido Simple , Caspasa 3/genética , Caspasa 9/genética , Genotipo , Neoplasias de Cabeza y Cuello/genética , Humanos , Recurrencia Local de Neoplasia/genética , Polimorfismo de Nucleótido Simple/genética , Estudios Prospectivos , Carcinoma de Células Escamosas de Cabeza y Cuello/genética
11.
BMC Oral Health ; 20(1): 116, 2020 04 16.
Artículo en Inglés | MEDLINE | ID: mdl-32299404

RESUMEN

BACKGROUND: The biologic width is defined as the coronal dimension to the alveolar bone that is occupied by healthy gingival tissue. The objective of the present study was to correlate radiographic findings of biologic width invasion with the periodontium status. METHODS: It were included 14 patients with restored teeth with biological width invasion, on the proximal sites, observed clinically and radiographically. 122 proximal sites were evaluated, 61 in the test group (biological width invasion) and 61 in the control group (adequate biological width). Smokers and patients presenting periodontal disease or restorations with contact in eccentric movements, horizontal over-contour or secondary caries were excluded from the sample. The invasion of the biologic width was diagnosed when the distance from the gingival margin of restoration to the bony crest was less than 3 mm. Intrabony defect and bone crest level, as well as, their vertical and horizontal components were radiographically evaluated when present. Plaque index, bleeding on probing, probing depth, gingival recession height, keratinized gingival height and thickness, and clinical attachment level were clinically evaluated. Data were subjected to Spearman's Correlation and Wilcoxon's test. RESULT: The most prevalent tooth with biological width invasion was the first molar. There was a statistically significant correlation between the bone crest (p < 0.001), vertical (p < 0.001) and horizontal (p = 0.001) components. In the test group, there was a statistically significant correlation between bleeding on probing (p < 0.001; r = 0.618) and width of gingival recession (p = 0.030; r = - 0.602) with the intraosseous component; and between keratinized gingival height and bone level (p = 0.037; r = - 0.267). In the control group, there was a correlation between plaque index (p = 0.027; r = - 0.283) with bone level and correlation between keratinized gingival thickness and bone level (p = 0.034; r = - 0.273) and intrabony component (p = 0.042; r = 0.226). CONCLUSION: A statistically significant relationship was found between bleeding on probing and gingival recession in patients who presented intrabony defects due to the invasion of biological width, which may be also related to the thickness of the keratinized gingiva.


Asunto(s)
Pérdida de Hueso Alveolar/diagnóstico por imagen , Productos Biológicos , Recesión Gingival/diagnóstico por imagen , Periodoncio/patología , Adulto , Pérdida de Hueso Alveolar/etiología , Estudios de Casos y Controles , Índice de Placa Dental , Femenino , Estudios de Seguimiento , Encía/diagnóstico por imagen , Encía/patología , Recesión Gingival/etiología , Recesión Gingival/patología , Humanos , Masculino , Persona de Mediana Edad , Pérdida de la Inserción Periodontal/diagnóstico por imagen , Pérdida de la Inserción Periodontal/etiología , Periodontitis/diagnóstico por imagen , Periodontitis/etiología , Prevalencia , Radiografía
12.
J Am Chem Soc ; 141(37): 14752-14763, 2019 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-31464132

RESUMEN

Can molecular dynamics simulations predict the mechanical behavior of protein complexes? Can simulations decipher the role of protein domains of unknown function in large macromolecular complexes? Here, we employ a wide-sampling computational approach to demonstrate that molecular dynamics simulations, when carefully performed and combined with single-molecule atomic force spectroscopy experiments, can predict and explain the behavior of highly mechanostable protein complexes. As a test case, we studied a previously unreported homologue from Ruminococcus flavefaciens called X-module-Dockerin (XDoc) bound to its partner Cohesin (Coh). By performing dozens of short simulation replicas near the rupture event, and analyzing dynamic network fluctuations, we were able to generate large simulation statistics and directly compare them with experiments to uncover the mechanisms involved in mechanical stabilization. Our single-molecule force spectroscopy experiments show that the XDoc-Coh homologue complex withstands forces up to 1 nN at loading rates of 105 pN/s. Our simulation results reveal that this remarkable mechanical stability is achieved by a protein architecture that directs molecular deformation along paths that run perpendicular to the pulling axis. The X-module was found to play a crucial role in shielding the adjacent protein complex from mechanical rupture. These mechanisms of protein mechanical stabilization have potential applications in biotechnology for the development of systems exhibiting shear enhanced adhesion or tunable mechanics.


Asunto(s)
Imagen Individual de Molécula/métodos , Proteínas Bacterianas/química , Fenómenos Mecánicos , Microscopía de Fuerza Atómica/métodos , Simulación de Dinámica Molecular , Ruminococcus/química
13.
Am J Physiol Heart Circ Physiol ; 317(7): H1-H12, 2019 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-31002284

RESUMEN

The purpose of the present study was to test the hypothesis that doxorubicin (DX) and cyclophosphamide (CY) adjuvant chemotherapy (CHT) acutely impairs neurovascular and hemodynamic responses in women with breast cancer. Sixteen women (age: 47.0 ± 2.0 yr; body mass index: 24.2 ± 1.5 kg/m) with stage II-III breast cancer and indication for adjuvant CHT underwent two experimental sessions, saline (SL) and CHT. In the CHT session, DX (60 mg/m2) and CY (600 mg/m2) were administered over 45 min. In the SL session, a matching SL volume was infused in 45 min. Muscle sympathetic nerve activity (MSNA) from peroneal nerve (microneurography), calf blood flow (CBF; plethysmography) and calf vascular conductance (CVC), heart rate (HR; electrocardiography), and beat-to-beat blood pressure (BP; finger plethysmography) were measured at rest before, during, and after each session. Venous blood samples (5 ml) were collected before and after both sessions for assessment of circulating endothelial microparticles (EMPs; flow cytometry), a surrogate marker for endothelial damage. MSNA and BP responses were increased (P < 0.001), whereas CBF and CVC responses were decreased (P < 0.001), during and after CHT session when compared with SL session. Interestingly, the vascular alterations were also observed at the molecular level through an increased EMP response to CHT (P = 0.03, CHT vs. SL session). No difference in HR response was observed (P > 0.05). Adjuvant CHT with DX and CY in patients treated for breast cancer increases sympathetic nerve activity and circulating EMP levels and, in addition, reduces muscle vascular conductance and elevates systemic BP. These responses may be early signs of CHT-induced cardiovascular alterations and may represent potential targets for preventive interventions. NEW & NOTEWORTHY It is known that chemotherapy regimens increase the risk of cardiovascular events in patients treated for cancer. Here, we identified that a single cycle of adjuvant chemotherapy with doxorubicin and cyclophosphamide in women treated for breast cancer dramatically increases sympathetic nerve activity and circulating endothelial microparticle levels, reduces the muscle vascular conductance, and elevates systemic blood pressure.


Asunto(s)
Antineoplásicos/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Ciclofosfamida/efectos adversos , Doxorrubicina/efectos adversos , Endotelio Vascular/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Sistema Nervioso Simpático/efectos de los fármacos , Adulto , Antineoplásicos/administración & dosificación , Antineoplásicos/uso terapéutico , Micropartículas Derivadas de Células/efectos de los fármacos , Quimioterapia Adyuvante , Ciclofosfamida/administración & dosificación , Ciclofosfamida/uso terapéutico , Doxorrubicina/administración & dosificación , Doxorrubicina/uso terapéutico , Femenino , Humanos , Persona de Mediana Edad , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/inervación , Nervio Peroneo/fisiología
14.
Mol Biol Rep ; 46(6): 6557-6563, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31587185

RESUMEN

The objective of this research was to assess the association of genetic polymorphisms related to intrinsic apoptosis pathway CASP8 rs3834129 and CASP3 rs4647601 with the risk, clinical and pathological aspects, and survival of oropharynx squamous cell carcinoma (OPSCC) patients that received cisplatin and radiotherapy. The genotypes were identified in 198 patients with OPSCC and 200 controls using polymerase chain reaction methods. Chi square or Fisher's exact test and logistic regression were applied for the detection of differences between groups. Patients' genotypes were statistically evaluated considering the event-free survival and overall analysis using Kaplan-Meier estimate and Cox regression. CASP3 rs4647601 GG genotype (44.4% vs. 30.0%, p = 0.03) and G allele (63.9% vs. 55.5%, p = 0.04) were more common in patients with OPSCC than in controls. Carriers of GG genotype and G allele were under 1.78-fold and 1.40-fold increased risk of OPSCC than others, respectively. The frequency of CASP8 rs3834129 DD genotype was higher in patients with OPSCC with poorly differentiated or undifferentiated tumors when compared to others (34.5% vs. 16.1%, p = 0.02). No influence of CASP8 and CASP3 polymorphisms on OPSCC patients' survival was seen in this study. Our results indicate that inherited genetic variants in the intrinsic apoptosis pathway related to CASP3 rs4647601 and CASP8 rs3834129 polymorphisms may be an important determinant of OPSCC risk and tumor cell differentiation.


Asunto(s)
Carcinoma de Células Escamosas/genética , Caspasa 3/genética , Caspasa 8/genética , Neoplasias Orofaríngeas/genética , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Anciano de 80 o más Años , Brasil , Carcinoma de Células Escamosas/mortalidad , Estudios de Casos y Controles , Diferenciación Celular , Progresión de la Enfermedad , Regulación hacia Abajo , Femenino , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Orofaríngeas/mortalidad , Pronóstico , Análisis de Supervivencia
15.
Mem Inst Oswaldo Cruz ; 114: e180452, 2019 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-30726343

RESUMEN

BACKGROUND: Studies aimed at validating canine visceral leishmaniasis diagnostic tests present heterogeneous results regarding test accuracy, partly due to divergences in reference standards used and different infection evolution periods in animals. OBJECTIVE: This study aimed to evaluate the accuracy of the rapid test-dual path platform (TR-DPP) (Biomanguinhos®), EIE-Leishmaniose-Visceral-Canina-Biomanguinhos (EIE-LVC) (Biomanguinhos®), enzyme-linked immunosorbent assay (ELISA) rK39 (in-house), and the direct agglutination test (DAT-Canis) against a reference standard comprising parasitological and molecular techniques. METHODS: A phase II/III validation study was carried out in sample sera from 123 predominantly asymptomatic dogs living in an area endemic for visceral leishmaniasis. FINDINGS: Sixty-nine (56.1%) animals were considered infected according to the reference standard. For each test, the sensitivity and specificity, respectively, were as follows: TR-DPP, 21.74% [confidence interval (CI)95% 13.64% to 32.82%] and 92.59% (CI95% 82.45% to 97.08%); EIE-LVC, 11.59% (CI95% 5.9% to 21.25%) and 90.74% (CI95% 80.09% to 95.98%); ELISA rK39, 37.68% (CI95% 27.18% to 49.48%) and 83.33% (CI95% 71.26% to 90.98%); and DAT-Canis, 18.84% (CI95% 11.35% to 29.61%) and 96.30% (CI95% 87.46% to 98.98%). CONCLUSION: We concluded that improving the sensitivity of serum testing for diagnosing asymptomatic dogs must constitute a priority in the process of developing new diagnostic tests to be used in the visceral leishmaniasis control program in Brazil.


Asunto(s)
Anticuerpos Antiprotozoarios/sangre , Pruebas Diagnósticas de Rutina/veterinaria , Enfermedades de los Perros/diagnóstico , Leishmania infantum/inmunología , Leishmaniasis Visceral/veterinaria , Pruebas de Aglutinación/veterinaria , Animales , Pruebas Diagnósticas de Rutina/normas , Perros , Ensayo de Inmunoadsorción Enzimática/veterinaria , Leishmaniasis Visceral/diagnóstico , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
Electrophoresis ; 38(22-23): 2940-2946, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28777449

RESUMEN

A bioreactor was built by means of immobilizing alpha-amylase from Aspergillus oryzae by encapsulation, through cryopolymerization of acrylamide monomers for the continuous starch hydrolysis. The starch hydrolysis was evaluated regarding pH, the concentration of immobilized amylase on cryogel, the concentration of starch solution and temperature. The maximum value for starch hydrolysis was achieved at pH 5.0, concentration of immobilized enzyme 111.44 mg amylase /gcryogel , concentration of starch solution 45 g/L and temperature of 35°C. The immobilized enzyme showed a conversion ratio ranging from 68.2 to 97.37%, depending on the pH and temperature employed. Thus, our results suggest that the alpha-amylase from A. oryzae immobilized on cryogel monoliths represents a potential process for industrial production of maltose from starch hydrolysis.


Asunto(s)
Reactores Biológicos , Criogeles/química , Enzimas Inmovilizadas/metabolismo , Almidón/metabolismo , alfa-Amilasas/metabolismo , Aspergillus oryzae , Enzimas Inmovilizadas/química , Proteínas Fúngicas/química , Proteínas Fúngicas/metabolismo , Concentración de Iones de Hidrógeno , Hidrólisis , Maltosa/metabolismo , Porosidad , Almidón/análisis , Almidón/química , Temperatura , alfa-Amilasas/química
17.
J Oral Pathol Med ; 46(10): 961-966, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28730665

RESUMEN

BACKGROUND: In the oral cavity, genomic instability is caused by long-term exposure to carcinogens. The aim of this study was to evaluate the relationship between smoking and DNA ploidy. METHODS: Cytological material was obtained from patients participating in the Outpatient Smoking Treatment Program of the Heart Institute (INCOR-HCFMUSP), and of the Discipline of Oral Medicine (ICT-UNESP). The inclusion criteria for all groups were the absence of a history of malignant tumors, absence of clinical signs of changes in the selected area, and alcohol consumption of less than 3 units per week. Group 1:30 smokers before smoking cessation treatment; Group 2:30 non-smokers; Group 3:30 ex-smokers abstinent for at least 1 year. Cytological smears were collected from the floor of the mouth and border of the tongue and stained by Feulgen. Aneuploidy was evaluated using the ACIS® III system. RESULTS: The Kruskal-Wallis test showed no statistically significant difference (P = .4383) between the groups studied. No association between tobacco consumption and aneuploidy was observed in group 1 (P = 1) or group 2 (P = .68; Fisher's exact test). CONCLUSION: Smoking was not associated with changes in DNA content or the incidence of aneuploidy in normal oral mucosa.


Asunto(s)
Aneuploidia , ADN , Fumar/genética , Adulto , Anciano , Anciano de 80 o más Años , ADN/análisis , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mucosa Bucal/química
19.
Trop Anim Health Prod ; 48(1): 95-101, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26433723

RESUMEN

The objective of this study was to evaluate the effect of increasing the supply of protein with different degradation rates on the performance and metabolism of growing Nellore cattle reared on Brachiaria brizantha cv. Marandu pasture during the transition period from the dry to rainy season. The experiment was installed on an area of 34 ha, divided into 12 paddocks with an average area of 2.85 ha. In the performance evaluation were utilized 72 recently weaned, non-castrated Nellore cattle with an initial body weight (BW) of 199 kg (SEM = 16). The following supplements were used: energy protein supplement containing 25% crude protein (CP) (C-25) and energy protein supplements containing 40% CP with one third highly degradable CP and two thirds poorly degradable CP (40-1/3NPN), one half highly degradable CP and one half poorly degradable CP (40-1/2NPN), and two thirds highly degradable CP and one third poorly degradable CP (40-2/3NPN). Higher protein degradation rates reduced supplement intake (P < 0.01). In the first period, animals consuming supplement 40-1/3NPN exhibited higher average daily gain (ADG) (0.30 kg/day), similar to that of animals receiving supplement 40-1/2NPN (P = 0.04). In the second period, supplement 40-2/3NPN resulted in lower ADG (0.19 kg/day less than the other supplements). There was no effect of supplement on animal performance in the third period (P > 0.10), when ADG was 0.56 kg/day. In conclusion, the response to supplementation is associated with interactions with characteristics of the forage canopy. Supplementation with a true protein source will be beneficial only during the early stage of the dry-rainy season transition period.


Asunto(s)
Alimentación Animal/análisis , Bovinos/fisiología , Dieta/veterinaria , Proteínas en la Dieta/administración & dosificación , Suplementos Dietéticos , Estaciones del Año , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Peso Corporal/fisiología , Proteínas en la Dieta/análisis , Digestión , Aumento de Peso
20.
Trop Anim Health Prod ; 48(7): 1315-21, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27349439

RESUMEN

Ingestive behavior of lambs fed diets consisting of fresh sugarcane with urea, bagasse treated with calcium oxide, and urea ammoniated sugarcane bagasse supplemented with concentrate mixture in 50:50 ratio were evaluated. For this, 34 wethers Santa Inês in their growing phase, with an average age of 3.0 ± 0.6 months and a mean initial live weight of 17.8± 5.2 kg were used. The animals were distributed in a completely randomized design and subjected to visual observation periods of 5 days, for 24 h a day, during the experimental period. Dry matter (DM) intake and intake efficiency of DM were higher (P < 0.05) for animals receiving fresh sugarcane with urea. The animals which were fed with bagasse treated with calcium oxide had higher (P < 0.05) consumption of neutral detergent fiber, longer feeding and chewing time (P < 0.05), and shorter (P < 0.05) idling time. The time spent on chewing the ruminal bolus did not differ from one diet to the other (P > 0.05). Grams of dry matter per ruminated bolus were similar among animals fed with fresh sugarcane and ammoniated bagasse (P > 0.05) but lower (P < 0.05) in animals fed with bagasse treated with calcium oxide. Rumination efficiency values, in grams of dry matter per hour, and grams of neutral detergent fiber per hour for all three diets were similar (P > 0.05) to those found for feeding efficiency. The number of feeding and rumination periods was not affected (P > 0.05) by diet. Based on the intake and ingestive behavior responses, the fresh sugarcane with urea compared to bagasse treated with calcium oxide and ammoniated bagasse was found to be the better alternative feed for use in lamb diets.


Asunto(s)
Crianza de Animales Domésticos , Dieta/veterinaria , Conducta Alimentaria/fisiología , Ovinos/fisiología , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Animales Recién Nacidos/fisiología , Brasil , Celulosa , Fibras de la Dieta , Rumen/fisiología , Saccharum , Clima Tropical
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