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1.
Appl Microbiol Biotechnol ; 108(1): 210, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38355912

RESUMO

The influence of pulp carryover on the efficiency of the xylanase (X) treatment of industrial unbleached and oxygen-delignified eucalypt kraft pulps (A1 and A2 pulps, with kappa number (KN) values of 16 and 10, respectively), collected at the same pulp mill, was studied regarding the consumption of bleaching chemicals and pulp bleachability. Another non-oxygen-delignified eucalyptus kraft pulp of KN 13 was received after the extended cooking from a different pulp mill (pulp B). The assays were performed with both lab-washed (carryover-free) and unwashed (carryover-rich) pulps. Both lab-washed and unwashed pulps with carryover were subjected to X treatment, the former being demonstrating considerably higher ClO2 savings than the pulps containing carryover. The savings of bleaching reagents were higher when the X stage was applied to the A1 pulp than to the A2 pulp. This advantage of A1 pulp, however, was not confirmed when using unwashed pulps. In contrast, the gains obtained from the X treatment of unwashed pulp A2 were practically as high as those observed for the lab-washed A2 pulp. Furthermore, a similar effect in X stage was recorded for unwashed pulps having close KN: oxygen-delignified A2 pulp and non-oxygen-delignified B pulp. The results suggest that pulp carryover and initial pH were the key factors relating to the effectiveness of X treatment. The application of X treatment to the A2 unwashed pulp (after the oxygen stage) not only saved 20% of the ClO2 and 10% of the sodium hydroxide, but also improved the brightness stability of the bleached pulp without affecting its papermaking properties. KEY POINTS: • Xylanase treatment boosts kraft pulp bleaching • Pulp carryover hinders the xylanase treatment • Nearly 20% of ClO2 and 10% NaOH savings can be reached using xylanase.


Assuntos
Oxigênio , Papel , Oxigênio/química
2.
Molecules ; 29(11)2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38893418

RESUMO

A set of 2-aryl-9-H or methyl-6-morpholinopurine derivatives were synthesized and assayed through radioligand binding tests at human A1, A2A, A2B, and A3 adenosine receptor subtypes. Eleven purines showed potent antagonism at A1, A3, dual A1/A2A, A1/A2B, or A1/A3 adenosine receptors. Additionally, three compounds showed high affinity without selectivity for any specific adenosine receptor. The structure-activity relationships were made for this group of new compounds. The 9-methylpurine derivatives were generally less potent but more selective, and the 9H-purine derivatives were more potent but less selective. These compounds can be an important source of new biochemical tools and/or pharmacological drugs.


Assuntos
Antagonistas de Receptores Purinérgicos P1 , Humanos , Relação Estrutura-Atividade , Antagonistas de Receptores Purinérgicos P1/farmacologia , Antagonistas de Receptores Purinérgicos P1/química , Receptores Purinérgicos P1/metabolismo , Estrutura Molecular , Adenina/análogos & derivados , Adenina/química , Adenina/farmacologia , Morfolinas/química , Morfolinas/farmacologia , Purinas/química , Purinas/farmacologia , Purinas/síntese química , Células CHO
3.
Artigo em Inglês | MEDLINE | ID: mdl-38907641

RESUMO

BACKGROUND: The DNA mismatch repair (MMR) system serves as a sophisticated guardian of the precise functioning of the human genome. Dysregulation within this system is linked to the oncogenesis process. Reduced expression of MMR system proteins identified in salivary gland tumors (SGTs) suggests an increased risk of tumoral occurrence. This study aims to analyze the expression of MMR proteins in SGTs and discuss the relevance of this association to the development of these neoplasms. MATERIAL AND METHODS: This review was conducted following the PRISMA guidelines and was registered in PROSPERO (CRD42023465590). A comprehensive search of the PubMed/MEDLINE, Web of Science, Scopus, Embase, and ProQuest (non-peer reviewed platform) was performed to answer the question "Do DNA MMR system proteins exhibit expression in SGTs?". The methodological quality of the selected studies was assessed using the JBI's Critical Appraisal Tool. RESULTS: A total of 142 patients with benign SGTs and 84 with malignant SGTs were included in this review. The literature analysis showed a notable reduction in the expression of DNA MMR system proteins (hHMS2, hMLH1, hMSH3 and hMSH6) in the percentage of marked cells. CONCLUSIONS: The reduction in the expression of the DNA MMR system proteins suggests an interesting correlation with the development of malignant and benign SGTs. Nevertheless, further investigations are warranted to better clarify the precision of measuring biomarker protein expression.

4.
Opt Lett ; 48(21): 5639-5642, 2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37910722

RESUMO

Dissipative quartic solitons have gained interest in the field of mode-locked lasers for their energy-width scaling which allows the generation of ultrashort pulses with high energies. Pursuing the characterization of such pulses, here we found soliton solutions of a distributed model for mode-locked lasers in the presence of either positive or negative fourth-order dispersion (4OD). We studied the impact the laser parameters may have on the profiles, range of existence, and energy-width relation of the output pulses. The most energetic and narrowest solutions occur for negative 4OD, with the energy having an inverse cubic dependence with the width in most cases. Our simulations showed that the spectral filtering has the biggest contribution in the generation of short (widths as low as 39 fs) and very energetic (391 nJ) optical pulses.

5.
Inorg Chem ; 62(20): 7932-7953, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37154533

RESUMO

A series of mononuclear non-oxido vanadium(IV) complexes, [VIV(L1-4)2] (1-4), featuring tridentate bi-negative ONS chelating S-alkyl/aryl-substituted dithiocarbazate ligands H2L1-4, are reported. All the synthesized non-oxido VIV compounds are characterized by elemental analysis, spectroscopy (IR, UV-vis, and EPR), ESI-MS, as well as electrochemical techniques (cyclic voltammetry). Single-crystal X-ray diffraction studies of 1-3 reveal that the mononuclear non-oxido VIV complexes show distorted octahedral (1 and 2) or trigonal prismatic (3) arrangement around the non-oxido VIV center. EPR and DFT data indicate the coexistence of mer and fac isomers in solution, and ESI-MS results suggest a partial oxidation of [VIV(L1-4)2] to [VV(L1-4)2]+ and [VVO2(L1-4)]-; therefore, all these three complexes are plausible active species. Complexes 1-4 interact with bovine serum albumin (BSA) with a moderate binding affinity, and docking calculations reveal non-covalent interactions with different regions of BSA, particularly with Tyr, Lys, Arg, and Thr residues. In vitro cytotoxic activity of all complexes is assayed against the HT-29 (colon cancer) and HeLa (cervical cancer) cells and compared with the NIH-3T3 (mouse embryonic fibroblast) normal cell line by MTT assay and DAPI staining. The results suggest that complexes 1-4 are cytotoxic in nature and induce cell death in the cancer cell lines by apoptosis and that a mixture of VIV, VV, and VVO2 species could be responsible for the biological activity.


Assuntos
Complexos de Coordenação , Camundongos , Humanos , Animais , Complexos de Coordenação/química , Fibroblastos , Células HeLa , Vanádio/química , Quelantes , Ligantes
6.
Chaos ; 33(8)2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38060792

RESUMO

We investigate the properties of time-dependent dissipative solitons for a cubic complex Ginzburg-Landau equation stabilized by nonlinear gradient terms. The separation of initially nearby trajectories in the asymptotic limit is predominantly used to distinguish qualitatively between time-periodic behavior and chaotic localized states. These results are further corroborated by Fourier transforms and time series. Quasiperiodic behavior is obtained as well, but typically over a fairly narrow range of parameter values. For illustration, two examples of nonlinear gradient terms are examined: the Raman term and combinations of the Raman term with dispersion of the nonlinear gain. For small quintic perturbations, it turns out that the chaotic localized states are showing a transition to periodic states, stationary states, or collapse already for a small magnitude of the quintic perturbations. This result indicates that the basin of attraction for chaotic localized states is rather shallow.

7.
Rev Neurol (Paris) ; 179(1-2): 114-117, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36473746

RESUMO

We describe four male patients with wasted-leg syndrome, with predominant asymmetric thigh atrophy and weakness that stabilized after a period of slow progression (follow-up 7-18 years). Two patients had an Indian ethnic background and two were Portuguese, without known Indian ancestry. Other mimicking disorders were excluded, but one Indian patient was later diagnosed with CADASIL. Electromyography (EMG) revealed severe chronic neurogenic changes in proximal leg muscles, and mild changes in distal leg muscles, but EMG of the upper limbs was normal. Upper motor neuron signs were absent clinically and on transcranial magnetic stimulation. This seems to represent a variant of the common wasted-leg syndrome presentation.


Assuntos
Esclerose Lateral Amiotrófica , Doença dos Neurônios Motores , Humanos , Masculino , Perna (Membro) , Doença dos Neurônios Motores/complicações , Doença dos Neurônios Motores/diagnóstico , Músculo Esquelético , Eletromiografia , Estimulação Magnética Transcraniana , Esclerose Lateral Amiotrófica/diagnóstico
8.
Chaos ; 32(12): 123107, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36587340

RESUMO

We study the time-dependent behavior of dissipative solitons (DSs) stabilized by nonlinear gradient terms. Two cases are investigated: first, the case of the presence of a Raman term, and second, the simultaneous presence of two nonlinear gradient terms, the Raman term and the dispersion of nonlinear gain. As possible types of time-dependence, we find a number of different possibilities including periodic behavior, quasi-periodic behavior, and also chaos. These different types of time-dependence are found to form quite frequently from a window structure of alternating behavior, for example, of periodic and quasi-periodic behaviors. To analyze the time dependence, we exploit extensively time series and Fourier transforms. We discuss in detail quantitatively the question whether all the DSs found for the cubic complex Ginzburg-Landau equation with nonlinear gradient terms are generic, meaning whether they are stable against structural perturbations, for example, to the additions of a small quintic perturbation as it arises naturally in an envelope equation framework. Finally, we examine to what extent it is possible to have different types of DSs for fixed parameter values in the equation by just varying the initial conditions, for example, by using narrow and high vs broad and low amplitudes. These results indicate an overlapping multi-basin structure in parameter space.

9.
Tech Coloproctol ; 26(11): 893-900, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35986806

RESUMO

BACKGROUND: High-resolution anoscopy (HRA) is the gold standard for detecting anal squamous cell cancer (ASCC) precursors. Although it is superior to other diagnostic methods, particularly cytology, the visual identification of areas suspected of having high-grade squamous intraepithelial lesions remains difficult. Convolutional neural networks (CNNs) have shown great potential for assessing endoscopic images. The aim of the present study was to develop a CNN-based system for automatic detection and differentiation of HSIL versus LSIL in HRA images. METHODS: A CNN was developed based on 78 HRA exams from a total of 71 patients who underwent HRA at a single high-volume center (GH Paris Saint-Joseph, Paris, France) between January 2021 and January 2022. A total of 5026 images were included, 1517 images containing HSIL and 3509 LSIL. A training dataset comprising 90% of the total pool of images was defined for the development of the network. The performance of the CNN was evaluated using an independent testing dataset comprising the remaining 10%. The sensitivity, specificity, accuracy, positive and negative predictive values, and area under the curve (AUC) were calculated. RESULTS: The algorithm was optimized for the automatic detection of HSIL and its differentiation from LSIL. Our model had an overall accuracy of 90.3%. The CNN had sensitivity, specificity, positive and negative predictive values of 91.4%, 89.7%, 80.9%, and 95.6%, respectively. The area under the curve was 0.97. CONCLUSIONS: The CNN architecture for application to HRA accurately detected precursors of squamous anal cancer. Further development and implementation of these tools in clinical practice may significantly modify the management of these patients.


Assuntos
Neoplasias do Ânus , Carcinoma de Células Escamosas , Lesões Intraepiteliais Escamosas , Neoplasias do Ânus/diagnóstico por imagem , Neoplasias do Ânus/patologia , Inteligência Artificial , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Humanos , Redes Neurais de Computação
10.
J Helminthol ; 96: e12, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35195063

RESUMO

The prevalence of vector-associated parasitic infections is high in central-southern Italy. The deltaic coastal plain of the Volturno River has been suspected, by veterinary practitioners, to have a high accidental incidence of Dirofilaria repens. Thus, the goal of this study was to evaluate the prevalence of dirofilariasis and other coinfections frequently described in dogs living in the Volturno area. Blood samples of 100 clinical asymptomatic dogs were examined using a Knott's technique and polymerase chain reaction in order to identify microfilariae. Other vector-borne coinfections were also investigated using ELISA kits. The results were analysed using statistical and Geographic Information System (GIS) software. Microfilariae of D. repens were detected in 10% of the dogs surveyed, with a presence of antibodies against Ehrlichia canis (4/10) and Dirofilaria immitis (1/10). Such high incidence should be considered in light of the zoonotic potential for D. repens and the support for more regular use of repellents to prevent the spread of this disease. The GIS analyses indicated that the study area provides suitable conditions to sustain populations of mosquito vectors and D. repens parasites throughout much of the year.


Assuntos
Dirofilaria immitis , Dirofilaria repens , Dirofilariose , Doenças do Cão , Animais , Dirofilariose/parasitologia , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Cães , Itália/epidemiologia , Prevalência
11.
Med Oral Patol Oral Cir Bucal ; 27(4): e392-e396, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35368007

RESUMO

BACKGROUND: Oral and oropharyngeal cancer (OPC) is an important cause of morbidity and mortality worldwide. Populations in situations of social vulnerability tend to have higher incidences of cancer, a higher proportion of late diagnosis, greater difficulties in accessing health services, and, consequently, worse prognosis. The aim of this study was to evaluate the relationship between race/skin color and OPC prognosis in Brazil. MATERIAL AND METHODS: This is a cross-sectional epidemiological study using OPC data from the National Cancer Institute between the years 2000 and 2019. The selected variables were: gender, race/skin color, age, education, smoking and alcohol consumption, stage of the disease and disease status at the end of the 1st treatment. RESULTS: 154,214 cases were recorded. Black men, in the 6th decade of life, were the most affected population. Blacks had a lower level of education when compared to non-blacks (p<0.001). Blacks were more exposed to smoking and alcohol consumption (p<0.001). At the time of diagnosis, the black population was at the most advanced stage when compared to non-blacks (p<0.001). At the end of the 1st treatment, more black patients had disease in progression, as well as more black patients died (p<0.001). CONCLUSIONS: Blacks had a worse prognosis for OPC in Brazil. Despite the limitations, these results are important to elucidate the scenario of health disparities in relation to the race/skin color of the Brazilian population.


Assuntos
Neoplasias Bucais , Neoplasias Orofaríngeas , Brasil/epidemiologia , Estudos Transversais , Humanos , Masculino , Neoplasias Bucais/epidemiologia , Neoplasias Orofaríngeas/epidemiologia , Prognóstico , População Branca
12.
Osteoporos Int ; 32(7): 1351-1358, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33479846

RESUMO

Although lactation is associated with transient bone loss and body weight changes, the unchanged TBS could highlight a limited effectiveness in detecting dynamic bone properties in the first year postpartum. PURPOSE: To evaluate trabecular bone score (TBS) and bone mineral density (BMD) in postpartum women. METHODS: This was a 12-month prospective cohort study with 40 lactating postpartum women and 44 non-pregnant women. The inclusion criteria were as follows: aged between 18 and 35 years old, an uncomplicated term (≥37 weeks) pregnancy with a single fetus, and no intention of becoming pregnant within 12 months. BMD measurements, including spine, hip, forearm and whole body, were performed by DXA at four different time points after delivery: (1) 1st month, (2) 3rd-4th month, (3) 6th-9th month, and (4) ≥ 12th month postpartum. RESULTS: BMD measurements showed a statistically significant decrease at spine (1.134 vs. 1.088 g/cm2, p < 0.01), femoral neck (0.988 vs. 0.946 g/cm2, p < 0.01), total femur (0.971 vs. 0.933 g/cm2, p < 0.01), and whole body (1.132 vs. 1.119 g/cm2, p = 0.03) at the 2nd assessment (peak of lactation). There was early spinal recovery after the 3rd assessment with complete recovery in all skeletal sites. Although it has had significant weight loss (67.3 vs. 63.2 kg, p < 0.01) and body mass index reduction (25.2 vs. 23.4, p < 0.01), there was significant increment of spine BMD (1.134 vs. 1.165 g/cm2, p < 0.01) after 12-month follow-up. The TBS did not change over time. CONCLUSIONS: Although lactation is associated with transient bone loss and body weight changes, the unchanged TBS could highlight a limited effectiveness in detecting dynamic bone properties in the first year postpartum.


Assuntos
Densidade Óssea , Osso Esponjoso , Absorciometria de Fóton , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Lactação , Vértebras Lombares/diagnóstico por imagem , Gravidez , Estudos Prospectivos
13.
Eur J Neurol ; 28(1): 202-208, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32918842

RESUMO

BACKGROUND AND PURPOSE: Experimental studies suggest inflammation can contribute to blood barrier disruption and brain injury in cerebral venous thrombosis (CVT). We aimed to determine whether blood biomarkers of inflammation were associated with the evolution of brain lesions, persistent venous occlusion or functional outcome in patients with CVT. METHODS: Pathophysiology of Venous Infarction-Prediction of Infarction and Recanalization in CVT (PRIORITy-CVT) was a multicenter prospective cohort study of patients with newly diagnosed CVT. Evaluation of neutrophil-to-lymphocyte ratio (NLR) and C-reactive protein (CRP) concentrations in peripheral blood samples was performed at admission in 62 patients. Additional quantification of interleukin (IL)-6 was performed at day 1, 3 and 8 in 35 patients and 22 healthy controls. Standardized magnetic resonance imaging was performed at day 1, 8 and 90. Primary outcomes were early evolution of brain lesion, early recanalization and functional outcome at 90 days. RESULTS: Interleukin-6 levels were increased in patients with CVT with a peak at baseline. IL-6, NLR and CRP levels were not related with brain lesion outcomes or early recanalization but had a significant association with unfavourable functional outcome at 90 days (IL-6: OR = 1.28, 95% CI: 1.05-1.56, P = 0.046; NLR: OR = 1.39, 95% CI: 1.4-1.87, P = 0.014; CRP: OR = 1.756, 95% CI: 1.010-3.051, P = 0.029). Baseline IL-6 had the best discriminative capacity, with an area under the receiver operating characteristic curve to predict unfavourable functional outcome of 0.74 (P = 0.031). CONCLUSIONS: Increased baseline levels of NLR, CRP and IL-6 may serve as new predictive markers of worse functional prognosis at 90 days in patients with CVT. No association was found between inflammatory markers and early evolution of brain lesion or venous recanalization.


Assuntos
Trombose Venosa , Biomarcadores , Humanos , Inflamação , Prognóstico , Estudos Prospectivos , Trombose Venosa/diagnóstico por imagem
14.
Ultrasound Obstet Gynecol ; 57(4): 614-623, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32196791

RESUMO

OBJECTIVE: To construct international ultrasound-based standards for fetal cerebellar growth and Sylvian fissure maturation. METHODS: Healthy, well nourished pregnant women, enrolled at < 14 weeks' gestation in the Fetal Growth Longitudinal Study (FGLS) of INTERGROWTH-21st , an international multicenter, population-based project, underwent serial three-dimensional (3D) fetal ultrasound scans every 5 ± 1 weeks until delivery in study sites located in Brazil, India, Italy, Kenya and the UK. In the present analysis, only those fetuses that underwent developmental assessment at 2 years of age were included. We measured the transcerebellar diameter and assessed Sylvian fissure maturation using two-dimensional ultrasound images extracted from available 3D fetal head volumes. The appropriateness of pooling data from the five sites was assessed using variance component analysis and standardized site differences. For each Sylvian fissure maturation score (left or right side), mean gestational age and 95% CI were calculated. Transcerebellar diameter was modeled using fractional polynomial regression, and goodness of fit was assessed. RESULTS: Of those children in the original FGLS cohort who had developmental assessment at 2 years of age, 1130 also had an available 3D ultrasound fetal head volume. The sociodemographic characteristics and pregnancy/perinatal outcomes of the study sample confirmed the health and low-risk status of the population studied. In addition, the fetuses had low morbidity and adequate growth and development at 2 years of age. In total, 3016 and 2359 individual volumes were available for transcerebellar-diameter and Sylvian-fissure analysis, respectively. Variance component analysis and standardized site differences showed that the five study populations were sufficiently similar on the basis of predefined criteria for the data to be pooled to produce international standards. A second-degree fractional polynomial provided the best fit for modeling transcerebellar diameter; we then estimated gestational-age-specific 3rd , 50th and 97th smoothed centiles. Goodness-of-fit analysis comparing empirical centiles with smoothed centile curves showed good agreement. The Sylvian fissure increased in maturation with advancing gestation, with complete overlap of the mean gestational age and 95% CIs between the sexes for each development score. No differences in Sylvian fissure maturation between the right and left hemispheres were observed. CONCLUSION: We present, for the first time, international standards for fetal cerebellar growth and Sylvian fissure maturation throughout pregnancy based on a healthy fetal population that exhibited adequate growth and development at 2 years of age. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Assuntos
Cerebelo/embriologia , Aqueduto do Mesencéfalo/embriologia , Desenvolvimento Fetal , Gráficos de Crescimento , Ultrassonografia Pré-Natal , Adulto , Brasil , Cerebelo/crescimento & desenvolvimento , Aqueduto do Mesencéfalo/crescimento & desenvolvimento , Pré-Escolar , Feminino , Idade Gestacional , Humanos , Índia , Lactente , Recém-Nascido , Itália , Quênia , Estudos Longitudinais , Masculino , Gravidez , Resultado da Gravidez , Padrões de Referência , Reino Unido
15.
J Dairy Sci ; 104(3): 3676-3692, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33455794

RESUMO

Our objective was to investigate the lipid content of uterus, blood plasma, and milk at early, mid, and late diestrus. Lactating cows (n = 30) had the estrous cycle and ovulation synchronized by administration of exogenous hormones. Cows were blocked by parity and assigned randomly to receive transcervical uterine flushing and biopsy on d 5 (early diestrus), 10 (mid diestrus) or 15 (late diestrus) of the estrous cycle. Flushing and endometrial biopsy were performed in the uterine horn ipsilateral to the corpus luteum. The recovered flushing was used for analyses of lipid composition by liquid chromatography-tandem mass spectrometry and the biopsy was used for investigation of lipid droplet abundance in endometrial cryosections using a neutral lipid fluorescent dye. In addition, blood and milk samples were collected from all cows on d 5, 10, and 15. All blood samples were used to measure the concentration of progesterone in plasma, and all milk samples were used to determine milk composition. Subsamples of blood plasma and milk were also used to evaluate the composition of fatty acids and oxylipins using the same methodology used for uterine flushing samples. The abundance of lipid droplets in the endometrium increased 1.9-fold from d 5 to 10, and 2-fold from d 10 to 15. Concentration of long-chain fatty acids and oxylipins in uterine flushing were, on average, 2.2 and 2.5 times greater in samples collected on d 15 compared with those collected on d 5 and 10. These differences were not observed in blood and milk, suggesting that accumulation of fatty acids and oxylipins in the uterus is regulated locally. In addition to concentration, the profile of individual fatty acids and oxylipins in uterine lumen changed substantially during diestrus. The main categories with increased abundance at late diestrus were mono- and polyunsaturated fatty acids, and oxylipins derived from arachidonic acid, dihomo-γ-linolenic acid, and docosahexaenoic acid. In conclusion, fatty acids and oxylipins accumulate in the uterine lumen during diestrus and might work as a mechanism to supply these lipids to the developing conceptus at late diestrus, when the onset of elongation occurs and substantial synthesis of biomass and cell signaling by lipid mediators are required.


Assuntos
Lactação , Leite , Animais , Bovinos , Diestro , Endométrio , Ácidos Graxos , Feminino , Gotículas Lipídicas , Oxilipinas , Gravidez , Útero
16.
Int Endod J ; 54(9): 1623-1637, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33829516

RESUMO

AIM: To compare six reciprocating instruments regarding their geometric design, metallurgical characteristics, mechanical behaviour and ability to prepare root canals. METHODOLOGY: A total of 246 new 25-mm NiTi instruments (41 per group) from six reciprocating systems (Reciproc, Reciproc Blue, One Files, One Files Blue, Reverso Silver, and WaveOne Gold) were evaluated throughout a multimethod approach regarding their design using stereomicroscopy (number of blades and helix angle) and scanning electron microscopy (blades symmetry, cross section and surface finishing), nickel-titanium composition, phase transformation temperatures, mechanical performance (cyclic fatigue, torsional and bending resistance) and unprepared canal surface area on anatomically matched mandibular molars assessed by micro-CT. One-way ANOVA and post hoc Tukey's or Mood's median tests were selected depending on sample distribution with significance level set at 5%. RESULTS: The instruments had similarities regarding their metal composition and unprepared canal area, whilst differences in phase transformation temperatures and geometric design (number of blades, surface finishing and tip geometry) were observed. Overall, no difference was observed regarding the maximum torque values (P > 0.05), whilst One Files (72 s) and One Files Blue (414 s) had the shortest and longest times to fracture, respectively (P < 0.05). Similar angles of rotation were observed in Reciproc (310°), One Files (285°) and Reverso Silver (318°) instruments (P > 0.05), which were significantly lower than Reciproc Blue (492°), One Files Blue (456°) and WaveOne Gold (492°; P < 0.05). Maximum bending load demonstrated that Reciproc Blue (201.3 gf) was significantly more flexible that the other instruments (P < 0.05). CONCLUSION: Although there were similarities in metal composition and percentage of unprepared canal surface, the instruments had differences in the overall geometric design, phase transformation temperatures and in the four mechanical resistance parameters (time to fracture, maximum torque, angle of rotation and maximum bending load).


Assuntos
Instrumentos Odontológicos , Preparo de Canal Radicular , Desenho de Equipamento , Teste de Materiais , Estresse Mecânico
17.
Int Endod J ; 54(5): 780-792, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33300121

RESUMO

AIM: To compare the ProTaper Next (PTN) system with a replica-like and a counterfeit system regarding design, metallurgy, mechanical performance and shaping ability. METHODOLOGY: Replica-like (X-File) and counterfeit (PTN-CF) instruments were compared to the PTN system regarding design (microscopy), phase transformation temperatures (differential scanning calorimetry), nickel-titanium ratio (energy-dispersive X-ray spectroscopy), cyclic fatigue, torsional resistance, bending strength, and untouched canal areas in extracted mandibular molars (micro-CT). anova, post hoc Tukey's and Kruskal-Wallis tests were used according to normality assessment (Shapiro-Wilk test) with the significance level set at 5%. RESULTS: Overall similarities in design and nickel-titanium (Ni/Ti) ratio were observed amongst instruments with the X-File having a smoother surface finish. PTN and PTN-CF had mixed austenite plus R-phase (R-phase start approximately at 45 ºC and near 30 ºC, respectively), whilst X-File instruments were austenitic (R-phase started at approximately at 17 ºC) at room temperature (20 ºC). PTN-CF had the greatest inconsistency in the phase transformation temperatures. Time to fracture of PTN-CF X2 and X3 was significantly shorter than PTN and X-File instruments (P < 0.05), whilst no difference was noted in maximum torque to fracture amongst the tested systems (P > 0.05). X-Files and PTN-CF had a stress-induced phase change during bending load. Mean unprepared surface areas of root canals were 25.8% (PTN), 31.1% (X-File) and 32.5% (PTN-CF) with no significant difference amongst groups (P > 0.05). CONCLUSION: Similarities amongst the systems were noted in the Ni/Ti ratio and maximum torque to fracture, whilst differences were observed in the design, phase transformation temperatures and mechanical behaviour. The ProTaper Next counterfeit instruments could be considered as the less secure system considering its low-cyclic fatigue resistance. Apart from these differences, the unprepared canal surface areas, obtained with the tested systems, were similar.


Assuntos
Ligas Dentárias , Preparo de Canal Radicular , Desenho de Equipamento , Teste de Materiais , Metalurgia , Estresse Mecânico , Titânio , Microtomografia por Raio-X
18.
Int Endod J ; 54(2): 279-293, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32920829

RESUMO

AIM: To validate a new method for the evaluation of pulp tissue debridement in the root canals of extracted teeth using an impregnation protocol involving potassium triiodide, a radiocontrast solution known as Lugol's, combined with micro-computed tomographic (micro-CT) imaging. METHODOLOGY: The impact of NaOCl on the radiopacity of Lugol's solution was assessed using a two-fold dilution series of Lugol in distilled water and 5.25% NaOCl, which were then pipetted into transparent dishes and radiographed. To verify the influence of Lugol on the proteolytic effect of NaOCl, a dissolution test was performed using fresh bovine meat. Ten slices did not undergo any tissue processing, whilst twenty slices were fixed in formaldehyde for 24 h. After that, 10 of them were immersed in Lugol for another 24 h. Then, all specimens were placed in NaOCl and the time required for a complete tissue dissolution was recorded. For the last experiments (histological validation and micro-CT assessment), 8 extracted mandibular premolars with formerly vital pulps were immersed in buffered formalin, scanned in a micro-CT device, accessed, immersed in Lugol for 7 days and scanned again. Then, the root canals of 5 teeth were prepared and scanned, and the volume of remaining pulp tissue identified and quantified, whilst 3 teeth were histologically processed. The same specimens were subjected to histological assessment, and the images of the histologic sections were registered with the corresponding micro-CT images to verify whether the pulp tissue in the histological sections matched its counterpart in the Lugol-impregnated tissues identified in the micro-CT slices. RESULTS: There was no discernible effect on radiopacity when NaOCl was mixed with Lugol's solution. Tissue processing did not affect the time required for the complete dissolution of fresh bovine meat. Histological evaluation revealed a correlation between micro-CT and histological images confirming the identification of Lugol-impregnated pulp tissue in micro-CT images. CONCLUSIONS: The radiocontrast Lugol's solution was unaffected by NaOCl and did not interfere with its soft tissue dissolution capability. The impregnation protocol using Lugol's solution allowed the visualization of pulp tissue on the micro-CT images and the identification of pulp remnants after chemical-mechanical canal procedures.


Assuntos
Cavidade Pulpar , Preparo de Canal Radicular , Animais , Bovinos , Desbridamento , Polpa Dentária , Cavidade Pulpar/diagnóstico por imagem , Microtomografia por Raio-X
19.
Med Oral Patol Oral Cir Bucal ; 26(6): e778-e785, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34023843

RESUMO

BACKGROUND: Oral Potentially Malignant Disorders (OPMDs) are defined as lesions with a greater likelihood of progressing to cancer. Population-based studies that evaluate the prevalence of OPMDs are scarce in Brazil. The aim of the present study was to determine the prevalence of OPMDs and associated risk factors in a semi-urban Brazilian population. MATERIAL AND METHODS: This is a cross-sectional study, whose universe included individuals aged 40 years or older residing in a medium-sized city of northeastern Brazil. Data collection was divided into two steps: interview and oral examination. The outcome variable was the presence of OPMDs. The predictor variables were sociodemographic characteristics and risk habits. The bivariate analysis was performed through chi-square test. The crude prevalence ratios (PR) and its respective 95% confidence intervals (CI) were calculated. Poisson regression analysis with robust variance was used to calculate adjusted PRs and 95% CI. RESULTS: Three hundred fourteen individuals were included in the study. When asked about risk habits, 58.9% reported being current smokers or ex-smokers and 62.2% reported being current drinkers or ex-drinkers. The prevalence of OPMDs was 7.6% and was significantly higher among individuals with black skin color (p < 0.001), alcohol users (p = 0.017), and individuals with both tobacco and alcohol habits (p = 0.012). CONCLUSIONS: Therefore, the population in the present study had a high frequency of risk habits associated with PMDs of the oral cavity.


Assuntos
Neoplasias Bucais , Brasil/epidemiologia , Estudos Transversais , Humanos , Neoplasias Bucais/epidemiologia , Prevalência , Fatores de Risco
20.
Hum Reprod ; 35(10): 2226-2236, 2020 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-32951048

RESUMO

STUDY QUESTION: Does the time elapsed between oocyte pick-up (OPU) and denudation or injection affect the probability of achieving a live birth (LB) in ICSI cycles? SUMMARY ANSWER: Prolonged oocyte culture before denudation (>4 h) was associated with an increase in clinical pregnancy (CP), LB and cumulative LB (CLB) rates when compared with earlier denudation timings. WHAT IS KNOWN ALREADY: Oocyte maturation is a complex and dynamic process involving structural and biochemical modifications in the cell necessary to support fertilization and early embryo development. While meiotic competence is easily identifiable by the presence of an extruded first polar body, cytoplasmic maturation cannot be assessed microscopically. Culturing oocytes with their surrounding cumulus cells (CCs) prior to ICSI can enhance the completion of in vitro cytoplasmic maturation; conversely, prolonged culture may induce cell degeneration. The optimal culture intervals prior to oocyte denudation and/or injection have not yet been established and may prove relevant for the improvement of ICSI reproductive outcomes. STUDY DESIGN, SIZE, DURATION: This is a single-centre retrospective cohort analysis of 1378 ICSI cycles performed between January 2005 and October 2018. Data were categorized according to: (i) the time interval between OPU and denudation (<3 h, 3-4 h and ≥4 h), (ii) the time interval between denudation and ICSI (<1.5 h, 1.5-2 h, ≥2 h) and (iii) the time interval between OPU and ICSI (<5 h, 5-6 h and ≥6 h). The effect of these timings on fertilization, CP, LB and CLB rates were compared. The culture intervals between different procedures were dependent exclusively on laboratory workload. PARTICIPANTS/MATERIALS, SETTING, METHODS: ICSI cycles performed in women younger than 40 years old using autologous gametes with at least one metaphase II injected oocyte were included. The effect of oocyte culture duration prior to denudation and injection of the oocytes was compared using multivariable regression accounting for potential confounding variables. MAIN RESULTS AND THE ROLE OF CHANCE: Fertilization and oocyte damage rate after ICSI was found to be independent of the time interval to denudation (<3 h, 3-4 h and ≥4 h) and/or injection (<5 h, 5-6 h and ≥6 h). Extending oocyte culture before denudation significantly improved CP (29.5%, 42.7% and 50.6%, respectively), LB (25.1%, 34.4% and 40.7%, respectively) and CLB rates (26.0%, 36.1% and 42.2%, respectively), particularly if the time interval was at least 4 h. Additionally, LB (31.7%, 35.8% and 27.4%, respectively) and CLB rates (34.2%, 36.6% and 27.7%, respectively) were also dependent on the time from OPU to injection. LIMITATIONS, REASONS FOR CAUTION: This study is limited by its retrospective nature and potential unmeasured confounding cannot be excluded. Furthermore, the effect of even shorter or longer periods of culture before denudation and/or injection were not evaluated and should not be extrapolated from these results. WIDER IMPLICATIONS OF THE FINDINGS: Our findings propose new evidence of a previously unrecognized protective effect of the CCs-oocyte interactions in human ART, raising the question of a possible downstream effect in embryogenesis which significantly affects LB rates. Additionally, this is the first study to suggest a negative effect of further extending culture before ICSI on LB and CLB rates, thus potentially allowing for the narrowing of an optimal ICSI time interval. Simple strategies such as the establishment of more effective time frames to perform these procedures and adjusting laboratory practice may prove beneficial, ultimately improving ICSI reproductive outcomes. STUDY FUNDING/COMPETING INTEREST(S): None. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Coeficiente de Natalidade , Injeções de Esperma Intracitoplásmicas , Adulto , Feminino , Fertilização in vitro , Humanos , Oócitos , Gravidez , Taxa de Gravidez , Estudos Retrospectivos
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