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1.
Neuroradiology ; 66(3): 317-323, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38183424

RESUMO

PURPOSE: After standard treatment for glioblastoma, perfusion MRI remains challenging for differentiating tumor progression from post-treatment changes. Our objectives were (1) to correlate rCBV values at diagnosis and at first tumor progression and (2) to analyze the relationship of rCBV values at tumor recurrence with enhancing volume, localization of tumor progression, and time elapsed since the end of radiotherapy in tumor recurrence. METHODS: Inclusion criteria were (1) age > 18 years, (2) histologically confirmed glioblastoma treated with STUPP regimen, and (3) tumor progression according to RANO criteria > 12 weeks after radiotherapy. Co-registration of segmented enhancing tumor VOIs with dynamic susceptibility contrast perfusion MRI was performed using Olea Sphere software. For tumor recurrence, we correlated rCBV values with enhancing tumor volume, with recurrence localization, and with time elapsed from the end of radiotherapy to progression. Analyses were performed with SPSS software. RESULTS: Sixty-four patients with glioblastoma were included in the study. Changes in rCBV values between diagnosis and first tumor progression were significant (p < 0.001), with a mean and median decreases of 32% and 46%, respectively. Mean rCBV values were also different (p < 0.01) when tumors progressed distally (radiation field rCBV values of 1.679 versus 3.409 distally). However, changes and, therefore, low rCBV values after radiotherapy in tumor recurrence were independent of time. CONCLUSION: Chemoradiation alters tumor perfusion and rCBV values may be decreased in the setting of tumor progression. Changes in rCBV values with respect to diagnosis, with low rCBV in tumor progression, are independent of time but related to the site of recurrence.


Assuntos
Neoplasias Encefálicas , Glioblastoma , Humanos , Adulto , Pessoa de Meia-Idade , Glioblastoma/diagnóstico por imagem , Glioblastoma/radioterapia , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/radioterapia , Recidiva Local de Neoplasia/diagnóstico por imagem , Meios de Contraste , Quimiorradioterapia , Imageamento por Ressonância Magnética/métodos
2.
Acta Ortop Mex ; 35(3): 252-256, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-34921533

RESUMO

INTRODUCTION: The rupture of the Achilles tendon is one of the most frequent of the lower limb, the increase in its incidence invites to evaluate its associated characteristics that act as triggers or as risk factors. METHODS: Descriptive, retrospective, cross-sectional study, based on clinical history data, using mean, standard deviation and percentages. RESULTS: We evaluated 49 patients: males 83.7%, administrative profession 46.9%, sport injury 61.2% (soccer 38.8%). 75.5% were acute injuries, affecting the left tendon (57.1%). The most referred symptom is sudden pain (95.9%) and the most common sign is Thompson's (89.8%). Ultrasonography was used in 42.9%. 95.5% received treatment by open surgery and spinal anesthesia 85.1%. Intraoperatively they reported complete rupture 95.7%, at 2-5 cm insertion 66%, 98% of them had no associated injuries. The repair was simple tenorrhaphy with Kessler's point (51%) and Vycril as suture material (95.7%). Immobilization was performed with warm-pedium plaster (98%) for a period of 6-8 weeks (91.9%). Surgical waiting was 3.6 days and hospital stay 4.9 days. CONCLUSIONS: Achilles tendon rupture occurred more frequently in sedentary males between 29-48 years, acute presentation in sports activity, affecting the left tendon. Most were complete ruptures located between 2-5 cm from its insertion, performing simple tenorrhaphy.


INTRODUCCIÓN: La ruptura del tendón de Aquiles es una de las más frecuentes del miembro inferior, el aumento de su incidencia invita a evaluar sus características asociadas que actúan como desencadenantes o como factores de riesgo. MÉTODOS: Estudio descriptivo, retrospectivo, transversal, según datos de historias clínicas, utilizando media, desviación estándar y porcentajes. RESULTADOS: Evaluamos 49 pacientes: varones 83.7%, profesión administrativa 46.9%, 61.2% lesión de deporte (fútbol 38.8%). De las lesiones, 75.5% fueron agudas afectando el tendón izquierdo (57.1%). El síntoma más referido fue dolor súbito (95.9%) y el signo más encontrado fue el de Thompson (89.8%). Se usó ecografía en 42.9%. Recibieron tratamiento por cirugía abierta 95.5% y anestesia espinal 85.1%. Intraoperatoriamente reportaron ruptura completa 95.7%, a 2-5 cm de inserción 66%, 98% de ellas no presentaron lesiones asociadas. La reparación fue tenorrafía simple con punto de Kessler (51%) y vycril como material de sutura (95.7%). Se realizó inmovilización con yeso tibio-pedio (98%) por lapso de seis a ocho semanas (91.9%). La espera quirúrgica fue 3.6 días y la estancia hospitalaria 4.9 días. CONCLUSIONES: La ruptura del tendón de Aquiles se observó con mayor frecuencia en varones sedentarios entre 29-48 años, presentación aguda en actividad deportiva afectando el tendón izquierdo. La mayoría fueron rupturas completas ubicadas entre 2-5 cm de su inserción, realizando tenorrafía simple.


Assuntos
Tendão do Calcâneo , Traumatismos dos Tendões , Tendão do Calcâneo/cirurgia , Estudos Transversais , Humanos , Masculino , Estudos Retrospectivos , Ruptura/cirurgia , Traumatismos dos Tendões/epidemiologia , Traumatismos dos Tendões/cirurgia
4.
Nat Commun ; 12(1): 3044, 2021 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-34031415

RESUMO

Unlike other malignancies, therapeutic options in pancreatic ductal adenocarcinoma (PDAC) are largely limited to cytotoxic chemotherapy without the benefit of molecular markers predicting response. Here we report tumor-cell-intrinsic chromatin accessibility patterns of treatment-naïve surgically resected PDAC tumors that were subsequently treated with (Gem)/Abraxane adjuvant chemotherapy. By ATAC-seq analyses of EpCAM+ PDAC malignant epithelial cells sorted from 54 freshly resected human tumors, we show here the discovery of a signature of 1092 chromatin loci displaying differential accessibility between patients with disease free survival (DFS) < 1 year and patients with DFS > 1 year. Analyzing transcription factor (TF) binding motifs within these loci, we identify two TFs (ZKSCAN1 and HNF1b) displaying differential nuclear localization between patients with short vs. long DFS. We further develop a chromatin accessibility microarray methodology termed "ATAC-array", an easy-to-use platform obviating the time and cost of next generation sequencing. Applying this methodology to the original ATAC-seq libraries as well as independent libraries generated from patient-derived organoids, we validate ATAC-array technology in both the original ATAC-seq cohort as well as in an independent validation cohort. We conclude that PDAC prognosis can be predicted by ATAC-array, which represents a low-cost, clinically feasible technology for assessing chromatin accessibility profiles.


Assuntos
Sequenciamento de Cromatina por Imunoprecipitação/métodos , Cromatina , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/genética , Biomarcadores Tumorais , Carcinoma Ductal Pancreático/diagnóstico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Núcleo Celular , Fator 1-beta Nuclear de Hepatócito/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Fatores de Transcrição Kruppel-Like/genética , Neoplasias Pancreáticas/metabolismo , Prognóstico , Fatores de Transcrição , Transcriptoma , Neoplasias Pancreáticas
7.
J Biomech Eng ; 143(1)2021 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-32766749

RESUMO

The estimation of human ankle's mechanical impedance is an important tool for modeling human balance. This work presents the implementation of a parameter-estimation approach based on a state-augmented extended Kalman filter (AEKF) to infer the ankle's mechanical impedance during quiet standing. However, the AEKF filter is sensitive to the initialization of the noise covariance matrices. In order to avoid a time-consuming trial-and-error method and to obtain a better estimation performance, a genetic algorithm (GA) is proposed to best tune the measurement noise (Rk) and process noise covariances (Q) of the extended Kalman filter (EKF). Results using simulated data show the efficacy of the proposed algorithm for parameter-estimation of a third-order biomechanical model. Experimental validation of these results is also presented. They suggest that age is an influencing factor in the human balance.


Assuntos
Algoritmos , Tornozelo , Fenômenos Biomecânicos
8.
Sci Rep ; 10(1): 15739, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-32978449

RESUMO

We used a randomized crossover experiment to estimate the effects of ozone (vs. clean air) exposure on genome-wide DNA methylation of target bronchial epithelial cells, using 17 volunteers, each randomly exposed on two separated occasions to clean air or 0.3-ppm ozone for two hours. Twenty-four hours after exposure, participants underwent bronchoscopy to collect epithelial cells whose DNA methylation was measured using the Illumina 450 K platform. We performed global and regional tests examining the ozone versus clean air effect on the DNA methylome and calculated Fisher-exact p-values for a series of univariate tests. We found little evidence of an overall effect of ozone on the DNA methylome but some suggestive changes in PLSCR1, HCAR1, and LINC00336 DNA methylation after ozone exposure relative to clean air. We observed some participant-to-participant heterogeneity in ozone responses.


Assuntos
Brônquios/cirurgia , Metilação de DNA/efeitos dos fármacos , Ozônio/farmacologia , Proteínas de Transferência de Fosfolipídeos/genética , RNA Longo não Codificante/genética , Receptores Acoplados a Proteínas G/genética , Adulto , Brônquios/química , Brônquios/efeitos dos fármacos , Broncoscopia , Estudos Cross-Over , Epigênese Genética , Feminino , Voluntários Saudáveis , Humanos , Masculino , Adulto Jovem
9.
Gastroenterol Hepatol ; 43(8): 431-438, 2020 Oct.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-32680732

RESUMO

AIM: To evaluate the efficacy and safety of endoscopic vacuum therapy (EVT) in the management of perforations and anastomotic leaks of the upper gastrointestinal tract. PATIENTS AND METHODS: This is a retrospective observational study which included patients who underwent EVT due to any upper gastrointestinal defect between April 2017 and February 2019 in three Spanish Hospitals. To this end, we used the only medical device approved to date for endoscopic use (Eso-SPONGEr; B. Braun Melsungen AG, Melsungen, Germany). RESULTS: 11 patients were referred for EVT of an anastomotic leak after esophagectomy (n=7), gastrectomy (n=2), esophageal perforation secondary to endoscopic Zenker's septomiotomy (n=1) and Boerhaave syndrome (n=1). The median size of the cavity was 8×3cm. The median delay between surgery and EVT was 7 days. The median of EVT duration was 28 days. The median number of sponges used was 7 and the mean period replacement was 3.7 days. In 10 cases (91%), the defect was successfully closed. In 9 cases (82%) clinical resolution of the septic condition was achieved. 5 patients presented some adverse event: 3 anastomotic strictures, 1 retropharyngeal pain and 1 case of new-onset pneumonia. The median hospital stay from the start of EVT was 45 days. 1 patient died owing to septic complications secondary to the anastomotic leak. CONCLUSION: EVT was successful in over 90% of perforations and anastomotic leaks of the upper gastrointestinal tract. Moreover, this is a safe therapy with only mild adverse events associated.


Assuntos
Fístula Anastomótica/cirurgia , Duodenopatias/cirurgia , Endoscopia Gastrointestinal , Perfuração Esofágica/cirurgia , Perfuração Intestinal/cirurgia , Tratamento de Ferimentos com Pressão Negativa/métodos , Ruptura Gástrica/cirurgia , Trato Gastrointestinal Superior/cirurgia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tratamento de Ferimentos com Pressão Negativa/efeitos adversos , Estudos Retrospectivos , Resultado do Tratamento
10.
New Microbes New Infect ; 35: 100677, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32405419

RESUMO

Human adenoviruses (HAdV) are well-known opportunistic pathogens of immunocompromised adult and pediatric patients but specific associations between HAdV species or individual HAdV types and disease are poorly understood. In this study we report the isolation of a novel HAdV-B2 genotype from two unrelated immunocompromised patients, both recipients of a hematopoietic cell transplant. In both patients, the course of HAdV infection is consistent with a scenario of reactivation of a latent virus rather than a primary opportunistic infection. Archived HAdV PCR-positive plasma, urine, and stool specimens were processed for virus isolation and detailed molecular characterization. Virus isolates were recovered from patient 1 from PCR-positive urine specimens obtained at days 103 and 116 after transplant in association with gross hematuria, and from a stool specimen obtained 138 days after transplant in association with diarrhea. An isolate was recovered from patient 2 from a PCR-positive urine specimen. Hexon and fiber gene amplification and sequencing were carried out for initial molecular typing, identifying the isolates as an intertypic recombinant with a HAdV-11-like hexon gene and a HAdV-77-like fiber gene. Comprehensive restriction fragment length polymorphism (RFLP) analysis was performed on viral DNA purified from urine and stool isolates, and next generation whole genome sequencing was carried out on purified viral genomic DNA. The genomes of the two isolated strains are 99.5% identical and represent the same RFLP genomic variant. The identified virus is a novel HAdV-B2 genotype designated HAdV-78 exhibiting a HAdV-11-like penton base, a HAdV-11-like hexon and a HAdV-77-like fiber (P11H11F77).

11.
Gynecol Oncol Rep ; 32: 100564, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32322647

RESUMO

We present the case of a 27-year old female with an ovarian tumor and alpha-fetoprotein (AFP) of 1210 ng/m, a right salpingo-oophorectomy was performed and had conservative complementary staging by gynecologic oncologists. The histopathological report was primary hepatoid carcinoma of the ovary (HCO), clinical stage IA, complementary treatment was adjuvant chemotherapy with BEP and remains clinical, imaging and biochemically disease free in three years follow up.

12.
J Dent Res ; 99(6): 730-738, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32315566

RESUMO

A broad range of fungi has been detected in molecular surveys of the oral mycobiome. However, knowledge is still lacking on interindividual variability of these communities and the ecologic and clinical significance of oral fungal commensals. In this cross-sectional study, we use internal transcribed spacer 1 amplicon sequencing to evaluate the salivary mycobiome in 59 subjects, 36 of whom were scheduled to receive cancer chemotherapy. Analysis of the broad population structure of fungal communities in the whole cohort identified 2 well-demarcated genus-level community types (mycotypes), with Candida and Malassezia as the main taxa driving cluster partitioning. The Candida mycotype had lower diversity than the Malassezia mycotype and was positively correlated with cancer and steroid use in these subjects, smoking, caries, utilizing a removable prosthesis, and plaque index. Mycotypes were also associated with metabolically distinct bacteria indicative of divergent oral environments, with aciduric species enriched in the Candida mycotype and inflammophilic bacteria increased in the Malassezia mycotype. Similar to their fungal counterparts, coexisting bacterial communities associated with the Candida mycotype showed lower diversity than those associated with the Malassezia mycotype, suggesting that common environmental pressures affected bacteria and fungi. Mycotypes were also seen in an independent cohort of 24 subjects, in which cultivation revealed Malassezia as viable oral mycobiome members, although the low-abundance Malassezia sympodialis was the only Malassezia species recovered. There was a high degree of concordance between the molecular detection and cultivability of Candida, while cultivation showed low sensitivity for detection of the Malassezia mycotype. Overall, our work provides insights into the oral mycobiome landscape, revealing 2 community classes with apparently distinct ecologic constraints and specific associations with coexisting bacteria and clinical parameters. The utility of mycotypes as biomarkers for oral diseases warrants further study.


Assuntos
Micobioma , Adulto , Idoso , Bactérias , Estudos Transversais , Feminino , Fungos , Humanos , Malassezia , Masculino , Pessoa de Meia-Idade , Micobioma/genética
13.
Opt Express ; 28(3): 4258-4273, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32122082

RESUMO

We report on measurements of high-order dispersion maps of an optical fiber, showing how the ratio between the third and fourth-order dispersion (ß3/ß4) and the zero-dispersion wavelength (λ0) vary along the length of the fiber. Our method is based on Four-Wave Mixing between short pulses derived from an incoherent pump and a weak laser. We find that the variations in the ratio ß3/ß4 are correlated to those in λ0. We present also numerical calculations to illustrate the limits on the spatial resolution of the method. Due to the good accuracy in measuring λ0 and ß3/ß4 (10 -3% and 5% relative error, respectively), and its simplicity, the method can be used to identify fiber segments of good uniformity, suitable to build nonlinear optical devices such as parametric amplifiers and frequency comb generators.

14.
Oper Dent ; 45(5): 516-527, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32101497

RESUMO

CLINICAL RELEVANCE: Achieving durable bonding to zirconia is fundamental for the application of a methacryloyloxydecyl dihydrogen phosphate (MDP)-containing silane solution or an MDP-containing silane solution associated with an MDP-containing universal adhesive. SUMMARY: Objectives: To evaluate the effect of a methacryloyloxydecyl dihydrogen phosphate (MDP)-containing silane coupling agent and universal adhesive, used alone or in combination, on the microshear bond strength (µSBS) to zirconia after 24 hours of water storage (24h) and after 10,000 thermocycles (TC), complemented with chemical analysis of the surface to establish the presence of MDP on the surface of the zirconia after bonding procedures.Methods and Materials: Thirty computer-aided design/computed-aided manufacturing blocks of zirconia were cut into four sections (6×6×6 mm) and sintered. Zirconia sections (n=96) were assigned to 24 groups according to three factors: 1) silane (no silane, Monobond S [MBS], Monobond P [MB+]), 2) adhesive + resin cement (no adhesive + Enforce [ENF], no adhesive + RelyX Ultimate [REX], Prime&Bond Elect + Enforce [PBE/ENF], Scotchbond Universal + RelyX Ultimate [SBU/REX]), and 3) thermocycling (no thermocycling [24h], 10,000 thermocycles [TC]). Upon silane/adhesive application, cylinder-shaped matrices were filled with resin cement and light cured. Specimens were tested in µSBS (1.0 mm/min) after 24h or TC. The µSBS data were analyzed using twoway ANOVA and Tukey's post hoc test (α=0.05). In addition, micro-Raman spectroscopy was used to analyze the zirconia surface for immediate chemical interaction analysis (n=24).Results: For the 24h condition, PBE/ENF resulted in lower mean µSBS than both groups with silane without PBE (MBS and MB+ groups; p<0.001). SBU alone or MB+ alone and MB+ associated with SBU showed the highest mean µSBS (p<0.001). For the TC condition, all groups showed a significant decrease in mean µSBS compared with those of 24h (p<0.001), with the exception of MB+ associated to SBU (p>0.05). However, the application of MB+ alone or MB+ associated to SBU resulted in higher mean µSBS (p<0.001) after TC than the remaining TC groups. In terms of chemical interaction, only the SBU groups, alone or combined with both of the silane agents, were associated with the methacrylate groups after rinsing.Conclusions: The results of the current study support the use of an MDP-containing silane solution or an MDP-containing silane solution associated with an MDP-containing universal adhesive for bonding to air-abraded zirconia, as a more stable bonding after thermocycling.


Assuntos
Colagem Dentária , Silanos , Cerâmica , Teste de Materiais , Metacrilatos , Cimentos de Resina , Resistência ao Cisalhamento , Propriedades de Superfície , Zircônio
15.
Iran J Vet Res ; 20(2): 96-104, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31531031

RESUMO

BACKGROUND: One of the factors limiting successful processing of alpaca (Vicugna pacos) semen is the viscosity of seminal plasma. The viscous nature of the collected ejaculate has hindered sperm cryopreservation as well as artificial insemination (AI) under field conditions. AIMS: The objective of this investigation was to evaluate recovery, motility, and plasma membrane integrity of alpaca spermatozoa after centrifugation in one of two different solutions at one of three different combinations of speed and time. METHODS: A total of 24 ejaculates was recovered from seven reproductively sound Huacaya males using a modified artificial vagina (AV) after training the animals for semen collection. A 2 × 3 factorial treatment arrangement was utilized for this study. Ejaculates were divided into fractions for centrifugation in one of two solutions (Tris extender or PureSperm®80 density gradient solution) at one of three combinations of speed and time (492 × g for 15 min, 1968 × g for 10 min, or 4448 × g for 7 min). The experiment was replicated eight times. RESULTS: Analysis revealed that centrifugation at 4448 × g for 7 min in PureSperm®80 provided a high recovery rate of spermatozoa with the highest sperm motility and functional integrity of plasma membrane post-centrifugation. Conclusion: Results suggest that adoption of this procedure (centrifugation at 4448 × g for 7 min in PureSperm®80) in the initial processing of alpaca ejaculates may enhance subsequent ability to use semen for AI and other assisted reproductive biotechnologies in this species.

16.
Clin Oral Investig ; 23(12): 4205-4212, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30806798

RESUMO

To determine Toll-like receptors (TLR)2 and TLR4 expression levels and associate them with matrix metalloproteinases (MMPs) in asymptomatic apical periodontitis (AAP), symptomatic apical periodontitis (SAP), and healthy controls. Apical tissue/lesion samples were obtained from chronic AAP (n = 35) and SAP (n = 29), and healthy periodontal ligament (HPL, n = 10) with indication of tooth extraction, respectively. mRNA expression levels of TLR2, TLR4, MMP-1, MMP-2, MMP-8, and MMP-13 were determined by real-time reverse-transcription polymerase chain reaction. The data were analyzed with Kruskal-Wallis and Dunn's pot hoc test (p < 0.05). The correlation coefficient was obtained using the Spearman correlation (p < 0.05). TLR2, MMP-1, MMP-2, and MMP-13 mRNA levels were the highest in SAP followed by AAP and controls (p < 0.05). TLR4 and MMP-8 were over expressed in AAP and SAP compared to HPL (p < 0.05). TLR2 positively correlated with TLR4, MMP-1, MMP-8, and MMP-13 in SAP (p < 0.05). TLR2 and TLR4 are overexpressed in apical lesions versus healthy periodontal ligament and correlate with collagenolytic MMPs. Particularly, TLR2 is overexpressed in SAP in association with MMP-1, MMP-8, and MMP-13. Our results suggest that the activation of TLR2 along with MMP overexpression might contribute to SAP clinical presentation and progression. TLRs, MMPs, and their interaction can explain the clinical presentations and evolution of apical periodontitis and might represent key targets for new diagnostic and treatment approaches.


Assuntos
Metaloproteinases da Matriz/metabolismo , Periodontite Periapical/metabolismo , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Estudos Transversais , Humanos , Periodontite Periapical/patologia , Ligamento Periodontal/efeitos dos fármacos , Ligamento Periodontal/metabolismo , Receptor 2 Toll-Like/genética , Receptor 4 Toll-Like/genética , Ápice Dentário/metabolismo
17.
J Mech Behav Biomed Mater ; 78: 352-361, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29202298

RESUMO

PURPOSE: To evaluate the immediate microshear resin-enamel bond strength (µSBS) and the immediate and 6-month microtensile bond strength (µTBS) and nanoleakage (NL) of the adhesive interface performed by different pHs of 40% meta-phosphoric acid (MPA) were compared with conventional 37% ortho-phosphoric acid (OPA) under different application times. Additionally, the enamel etching patterns were evaluated and the chemical/morphological changes induced by these differents groups were evaluated. MATERIALS AND METHODS: One hundred and ninety-eight extracted human molars were randomly assigned into experimental groups according to the combination of independent variables: Acid [37% ortho-phosphoric acid (OPA), 40% meta-phosphoric acid (MPA) at pHs of: 0.5, 1 and 2] and Application Time [7, 15 and 30s]. Enamel-bond specimens were prepared and tested under µSBS. Resin-dentin beams were tested under µTBS tested immediately or after 6-months of water storage. Nanoleakage was evaluated using bonded-beams of each tooth/time-period. Enamel etching pattern and chemical and ultra-morphology analyses were also performed. The µSBS (MPa) data were subjected to a two-way repeated measures ANOVA (Acid vs. Application time). For µTBS, Acid vs application time vs storage time data were subjected to three-way ANOVA and Tukey's test (α = 0.05). RESULTS: MPA pH 0.5 showed µTBS similar to OPA, independently of the application time on enamel (p>0.05) or dentin (p>0.05). OPA provided higher nanoleakage values than MPA (p = 0.003). Significant decreases in TBS and increases in NL were only observed for OPA after 6 months (p = 0.001). An increase in the application time resulted in a more pronounced etching pattern for MPA. Chemical analysis showed that dentin demineralized by MPA depicted peaks of brushite and octacalcium phosphate. MPA exposed less collagen than OPA. However, optimal results for MPA were dependent on pH/application time. CONCLUSION: The use of 40% meta-phosphoric acid with a pH of 0.5 is an alternative acid-etching agent for dentin and enamel bonding. Furthermore, the use of MPA preserves the resin-dentin interface over a 6-months period, due to presence of brushite and octacalcium phosphate and a reduced demineralization pattern.


Assuntos
Colagem Dentária , Esmalte Dentário/química , Esmalte Dentário/efeitos dos fármacos , Ácidos Fosfóricos/química , Ácidos Fosfóricos/farmacologia , Resinas Sintéticas/química , Humanos , Concentração de Íons de Hidrogênio , Isomerismo , Resistência à Tração
18.
Bull Entomol Res ; 108(4): 532-539, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29103385

RESUMO

The subterranean termite Reticulitermes grassei Clément causes lesions in the trunk of Quercus suber L. by constructing feeding galleries, but no information is available regarding other Quercus species from the Mediterranean region. This work aimed to study the suitability of the other main oak species of Mediterranean forests as a food resource for R. grassei. Two experiments, choice and non-choice feeding, were conducted lasting for 15, 30, and 45 days each. In the non-choice experiment, termites were offered one of the following food types: Quercus suber, Quercus ilex L., Quercus faginea Lam, cork or Pinus pinea L., which was considered the control. The choice feeding experiment used all the same food types listed above, supplied simultaneously in the same container. Food selection was examined by analysing the relationships over time between surviving termites and food consumption. The results indicated that R. grassei could be considered a generalist species, as it consumed the cork and wood of all oak species, as well as displaying a clear preference for soft wood (pine). Correlation analysis indicated that consumption was not dependent on wood density. Survival of R. grassei was influenced by the time of exposure to different oak species, but a high survival rate was maintained over time in the pine treatment (upper 70% in the three experiments). Given these results, it can be concluded that all the oak species are a suitable food source for R. grassei.


Assuntos
Isópteros/fisiologia , Quercus/parasitologia , Animais , Alimentos , Espanha
19.
Med. interna Méx ; 33(5): 655-667, sep.-oct. 2017. tab
Artigo em Espanhol | LILACS | ID: biblio-894307

RESUMO

Resumen: La porfiria intermitente aguda es la más frecuente de las porfirias hepáticas agudas. Ésta es causada por mutaciones de herencia autosómica dominante en el gen HMBS, que generan déficit de la enzima porfobilinógeno desaminasa en la vía biosintética del grupo hemo. Se caracteriza por síntomas neuroviscerales potencialmente letales, que incluyen dolor abdominal, vómito, estreñimiento, debilidad muscular, convulsiones. Estos ataques son desencadenados por medicamentos, ayuno, alcohol, cambios hormonales, estrés, entre otros. Su tratamiento incluye altas cargas de carbohidratos, hemina intravenosa y soporte médico. Algunos pacientes que padecen ataques agudos recurrentes pueden requerir hemina profiláctica o análogos de la hormona liberadora de gonadotropina. El trasplante hepático está indicado para los pacientes resistentes a esos tratamientos. Las complicaciones crónicas de la enfermedad incluyen carcinoma hepatocelular, hipertensión arterial, enfermedad renal crónica y dolor crónico.


Abstract: Acute intermittent porphyria is the most frequent of the acute hepatic porphyrias. This is caused by mutations of autosomal dominant inheritance in the HMBS gene, which generate a deficiency of the enzyme porphobilinogen deaminase in the biosynthetic pathway of the heme group. It is characterized by potentially life-threatening neurovisceral symptoms, including abdominal pain, vomiting, constipation, muscle weakness and seizures. Such attacks are triggered by medications, fasting, alcohol, hormonal changes, stress, among others. Its treatment includes high carbohydrate loads, intravenous hemin, and medical support. Some patients who develop recurrent acute attacks may require prophylactic hemin or gonadotropin-releasing hormone analogs. Liver transplantation is indicated for patients refractory to those treatments. Chronic complications of the disease include hepatocellular carcinoma, hypertension, chronic kidney disease, and chronic pain.

20.
Aliment Pharmacol Ther ; 46(9): 816-824, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28892178

RESUMO

BACKGROUND: Chylous ascites is rare, accounting for less than 1% of cases. An appropriate and stepwise approach to its diagnosis and management is of key importance. AIM: To review the current diagnostic approach and management of chylous ascites. METHODS: A literature search was conducted using PubMed using the key words 'chylous', 'ascites', 'cirrhosis', 'pathophysiology', 'nutritional therapy', 'paracentesis", "transjugular intrahepatic portosystemic shunt" and "TIPSS'. Only articles in English were included. RESULTS: Chylous ascites is caused by the traumatic or obstructive disruption of the lymphatic system that leads to extravasation of thoracic or intestinal lymph into the abdominal space and the accumulation of a milky fluid rich in triglycerides. The most common causes are malignancy, cirrhosis and trauma after abdominal surgery. This condition can lead to chyle depletion, which results in nutritional, immunologic and metabolic deficiencies. An ascitic triglyceride concentration above 200 mg/dL is consistent with chylous ascites. Treatment is based on management of the underlying cause and nutritional support. CONCLUSIONS: Chylous ascites is mostly due to malignancy and cirrhosis in adults, and congenital lymphatic disorders in children. Treatment with nutritional optimization and management of the underlying etiology are the cornerstones of therapy. When conservative measures fail, other interventions such as octreotide/somatostatin analogues, surgical ligation, embolization and transjugular intrahepatic portosystemic shunt in patients with cirrhosis can be considered.


Assuntos
Ascite Quilosa , Ascite Quilosa/diagnóstico , Ascite Quilosa/etiologia , Ascite Quilosa/terapia , Humanos , Cirrose Hepática/complicações , Doenças Linfáticas/complicações , Neoplasias/complicações , Ferimentos e Lesões/complicações
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