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1.
Hum Reprod ; 39(8): 1684-1691, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38822675

RESUMO

STUDY QUESTION: What is the relationship between late follicular phase progesterone levels and clinic pregnancy and live birth rates in couples with unexplained infertility undergoing ovarian stimulation with IUI (OS-IUI)? SUMMARY ANSWER: Late follicular progesterone levels between 1.0 and <1.5 ng/ml were associated with higher live birth and clinical pregnancy rates while the outcomes in groups with higher progesterone levels did not differ appreciably from the <1.0 ng/ml reference group. WHAT IS KNOWN ALREADY: Elevated late follicular progesterone levels have been associated with lower live birth rates after fresh embryo transfer following controlled ovarian stimulation and egg retrieval, but less is known about whether an association exists with outcomes in OS-IUI cycles. Existing studies are few and have been limited to ovarian stimulation with gonadotrophins, but the use of oral agents, such as clomiphene citrate and letrozole, is common with these treatments and has not been well studied. STUDY DESIGN, SIZE, DURATION: The study was a prospective cohort analysis of the Assessment of Multiple Intrauterine Gestations from Ovarian Stimulation (AMIGOS) randomized controlled trial. Frozen serum was available for evaluation from 2121 cycles in 828 AMIGOS participants. The primary pregnancy outcome was live birth per cycle, and the secondary pregnancy outcome was clinical pregnancy rate per cycle. PARTICIPANTS/MATERIALS, SETTING, METHODS: Couples with unexplained infertility in the AMIGOS trial, for whom female serum from day of trigger with hCG was available in at least one cycle of treatment, were included. Stored frozen serum samples from day of hCG trigger during treatment with OS-IUI were evaluated for serum progesterone level. Progesterone level <1.0 ng/ml was the reference group for comparison with progesterone categorized in increments of 0.5 ng/ml up to ≥3.0 ng/ml. Unadjusted and adjusted risk ratios (RR) and 95% CI were estimated using cluster-weighted generalized estimating equations to estimate modified Poisson regression models with robust standard errors. MAIN RESULTS AND THE ROLE OF CHANCE: Compared to the reference group with 110/1363 live births (8.07%), live birth rates were significantly increased in cycles with progesterone 1.0 to <1.5 ng/ml (49/401 live births, 12.22%) in both the unadjusted (RR 1.56, 95% CI 1.14, 2.13) and treatment-adjusted models (RR 1.51, 95% CI 1.10, 2.06). Clinical pregnancy rates were also higher in this group (55/401 clinical pregnancies, 13.72%) compared to reference group with 130/1363 (9.54%) (unadjusted RR 1.46, 95% CI 1.10, 1.94 and adjusted RR 1.42, 95% CI 1.07, 1.89). In cycles with progesterone 1.5 ng/ml and above, there was no evidence of a difference in clinical pregnancy or live birth rates relative to the reference group. This pattern remained when stratified by ovarian stimulation treatment group but was only statistically significant in letrozole cycles. LIMITATIONS, REASONS FOR CAUTION: The AMIGOS trial was not designed to answer this clinical question, and with small numbers in some progesterone categories our analyses were underpowered to detect differences between some groups. Inclusion of cycles with progesterone values above 3.0 ng/ml may have included those wherein ovulation had already occurred at the time the IUI was performed. These cycles would be expected to experience a lower success rate but pregnancy may have occurred with intercourse in the same cycle. WIDER IMPLICATIONS OF THE FINDINGS: Compared to previous literature focusing primarily on OS-IUI cycles using gonadotrophins, these data include patients using oral agents and therefore may be generalizable to the wider population of infertility patients undergoing IUI treatments. Because live births were significantly higher when progesterone ranged from 1.0 to <1.5 ng/ml, further study is needed to clarify whether this progesterone range may truly represent a prognostic indicator in OS-IUI cycles. STUDY FUNDING/COMPETING INTEREST(S): Oklahoma Shared Clinical and Translational Resources (U54GM104938) National Institute of General Medical Sciences (NIGMS). AMIGOS was funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development: U10 HD077680, U10 HD39005, U10 HD38992, U10 HD27049, U10 HD38998, U10 HD055942, HD055944, U10 HD055936, and U10HD055925. Research made possible by the funding by American Recovery and Reinvestment Act. Dr Burks has disclosed that she is a member of the Board of Directors of the Pacific Coast Reproductive Society. Dr Hansen has disclosed that he is the recipient of NIH grants unrelated to the present work, and contracts with Ferring International Pharmascience Center US and with May Health unrelated to the present work, as well as consulting fees with May Health also unrelated to the present work. Dr Diamond has disclosed that he is a stockholder and a member of the Board of Directors of Advanced Reproductive Care, Inc., and that he has a patent pending for the administration of progesterone to trigger ovulation. Dr Anderson, Dr Gavrizi, and Dr Peck do not have conflicts of interest to disclose. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Inseminação Artificial , Indução da Ovulação , Resultado da Gravidez , Progesterona , Humanos , Feminino , Gravidez , Indução da Ovulação/métodos , Progesterona/sangue , Inseminação Artificial/métodos , Adulto , Taxa de Gravidez , Nascido Vivo , Estudos Prospectivos , Fase Folicular , Infertilidade/terapia , Infertilidade/sangue , Coeficiente de Natalidade , Masculino
2.
Nat Mater ; 21(1): 54-61, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34608284

RESUMO

The properties of quantum materials are commonly tuned using experimental variables such as pressure, magnetic field and doping. Here we explore a different approach using irreversible, plastic deformation of single crystals. We show that compressive plastic deformation induces low-dimensional superconductivity well above the superconducting transition temperature (Tc) of undeformed SrTiO3, with evidence of possible superconducting correlations at temperatures two orders of magnitude above the bulk Tc. The enhanced superconductivity is correlated with the appearance of self-organized dislocation structures, as revealed by diffuse neutron and X-ray scattering. We also observe deformation-induced signatures of quantum-critical ferroelectric fluctuations and inhomogeneous ferroelectric order using Raman scattering. Our results suggest that strain surrounding the self-organized dislocation structures induces local ferroelectricity and quantum-critical dynamics that strongly influence Tc, consistent with a theory of superconductivity enhanced by soft polar fluctuations. Our results demonstrate the potential of plastic deformation and dislocation engineering for the manipulation of electronic properties of quantum materials.

3.
J Contemp Dent Pract ; 22(5): 557-561, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34318777

RESUMO

AIM AND OBJECTIVE: The purpose of this study was to measure the refractive index of four commercially available enamel resin composites, using optical coherence tomography (OCT) and their relationship with the atomic composition of the composite resin fillers utilizing an energy-dispersive X-ray fluorescence spectrometer (EDX). MATERIALS AND METHODS: Four different enamel composites, namely Enamel HRi color UE3, Enamel HFO color GE3, Vit-l-escence color Pearl Frost, and Amelogen Plus color Enamel White were tested. For each composite, disks with different thicknesses were fabricated and then light-cured according to the manufacturer's instructions. The disks were then stored in deionized water under 36.5 °C for at least 7 days. Each of the samples from the four different groups was measured in five distinctive points to analyze the optical and physical length using optical coherence tomography (OCT). Elemental analysis of all four different enamel shades of the composite was done using an EDX. RESULTS: The filler contents showed interesting differences in elemental composition and concentration; however, Si seemed to be a common filler component. The HRi composite presented a distinctive composition compared to other materials and was the only composite that showed a smaller percentage of SiO2, and also was the only composite that contained compounds, such as P2O5, ZnO, CaO, La2O3, and V2O5. The optical coherence tomography analysis showed the refractive index values of all tested enamel composites. Among the four different enamel composite resins tested, the enamel HRi composite demonstrated the most ideal refractive index to mimic natural enamel. CONCLUSION: The enamel HRi composite demonstrated a distinctive filler composition and this could be the main reason behind its higher refractive index. Nonetheless, it remains unclear how much of an impact this feature has in the final esthetic outcome of anterior composite restorations, where many other optical phenomena are also important. CLINICAL SIGNIFICANCE: The clinical success of any esthetic restorative procedure depends on diagnosing the proper treatment plan and also on executing this treatment with the right materials. On direct esthetic restorations, knowing the optical properties of such materials is fundamental, as they should be able to replicate both natural enamel and dentin. How to cite this article: Beolchi RS, Mehta D, Pelissier B, et al. Influence of Filler Composition on the Refractive Index of Four Different Enamel Shades of Composite Resins. J Contemp Dent Pract 2021;22(5):557-561.


Assuntos
Materiais Dentários , Refratometria , Cor , Resinas Compostas , Esmalte Dentário , Estética Dentária , Teste de Materiais , Dióxido de Silício
4.
Int J Mol Sci ; 19(2)2018 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-29389868

RESUMO

This in vitro study evaluated the compositional, crystalline, and morphological effects promoted by Nd:YAG laser on root dentin, and verified the effects of laser and topical acidulated phosphate fluoride application (APF-gel) on dentin erosion. 180 bovine dentin slabs were randomized into 4 groups (n = 45): G1-untreated, G2-APF-gel (1.23% F-, 4 min), G3-Nd:YAG (1064 nm, 84.9 J/cm², 10 Hz), and G4-APF-gel application followed by Nd:YAG laser irradiation. The compositional, crystalline, and morphological effects promoted by treatments were investigated on five samples of each experimental group. The other samples were submitted to a 5-day, 10-day, or 15-day erosive and abrasive demineralization and remineralization cycling in order to create erosion lesions. The area and depth of lesions, as well as the optical attenuation coefficient, were assessed, and all data were statistically analysed (p < 0.05). Nd:YAG laser promoted the reduction of carbonate, the formation of tetracalcium phosphate, as well as the melting and recrystallization of the dentin surface. Laser significantly decreased the area and depth of erosion lesions and altered the optical attenuation coefficient when compared to untreated and APF-gel groups, but the association of APF-gel and laser did not promote an additional effect. Nd:YAG laser irradiation can be a promissory treatment to prevent dentin erosion and the abrasion process.


Assuntos
Fluoreto de Fosfato Acidulado/farmacologia , Dentina/efeitos dos fármacos , Dentina/efeitos da radiação , Lasers de Estado Sólido , Erosão Dentária/prevenção & controle , Animais , Bovinos , Cristalização , Dentina/química , Microscopia Eletrônica de Varredura , Estrutura Molecular , Distribuição Aleatória , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Raiz Dentária/química , Raiz Dentária/efeitos dos fármacos , Raiz Dentária/efeitos da radiação
5.
Lasers Surg Med ; 46(9): 666-71, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25164563

RESUMO

BACKGROUND AND OBJECTIVE: We aimed to evaluate in the same study two quantitative methods for quantification of incipient caries in human dental enamel by using optical coherence tomography (OCT): the optical attenuation coefficient and the area under the A-scan signal, and to compare their results with those obtained from microhardness analysis. STUDY DESIGN/MATERIALS AND METHODS: One hundred and sixty samples were obtained from 40 sound human third molars, which had their crowns sectioned. Simulated caries were created by a pH cycling method. OCT measurements were performed on the samples, before and after the induced demineralization. We determined the total optical attenuation coefficient from the OCT signal in each site and evaluated the sensitivity and specificity of this approach to the detection of the demineralization. Also, the areas under the OCT curves (AUC-OCT) and those from sectional microhardness tests (AUC-MH) were compared. RESULTS: Both the analysis of the optical attenuation coefficient and the AUC-OCT were adequate to efficiently distinguish sound and demineralized samples with sensitivity of 0.93 and specificity of 0.96. The AUC-MH and the AUC-OCT data presented linear relationship and correlation of 0.99. CONCLUSION: Both methods for signal analysis from OCT allowed detection of demineralization with good performance. The AUC-OCT approach enables obtaining a linear relation with the microhardness results, for a quantitative assessment of mineral loss in human teeth.


Assuntos
Cárie Dentária/diagnóstico , Testes de Dureza , Dente Serotino , Tomografia de Coerência Óptica , Área Sob a Curva , Cárie Dentária/etiologia , Esmalte Dentário/patologia , Humanos , Sensibilidade e Especificidade , Técnicas de Cultura de Tecidos
6.
Brain Struct Funct ; 229(7): 1737-1756, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39042140

RESUMO

Oxytocin (OXT) is a peptide hormone and a neuropeptide that regulates various peripheral physiological processes and modulates behavioral responses in the central nervous system. While the humoral release occurs from the axons arriving at the median eminence, the neuropeptide is also released from oxytocinergic cell axons in various brain structures that contain its receptor, and from their dendrites in hypothalamic nuclei and potentially into the cerebrospinal fluid (CSF). Understanding oxytocin's complex functions requires the knowledge on patterns of oxytocinergic projections in relationship to its receptor (OXTR). This study provides the first comprehensive examination of the oxytocinergic system in the prairie vole (Microtus ochrogaster), an animal exhibiting social behaviors that mirror human social behaviors linked to oxytocinergic functioning. Using light and electron microscopy, we characterized the neuroanatomy of the oxytocinergic system in this species. OXT+ cell bodies were found primarily in the hypothalamus, and axons were densest in subcortical regions. Examination of the OXT+ fibers and their relationship to oxytocin receptor transcripts (Oxtr) revealed that except for some subcortical structures, the presence of axons was not correlated with the amount of Oxtr across the brain. Of particular interest, the cerebral cortex that had high expression of Oxtr transcripts contained little to no fibers. Electron microscopy is used to quantify dense cored vesicles (DCV) in OXT+ axons and to identify potential axonal release sites. The ependymal cells that line the ventricles were frequently permissive of DCV-containing OXT+ dendrites reaching the third ventricle. Our results highlight a mechanism in which oxytocin is released directly into the ventricles and circulates throughout the ventricular system, may serve as the primary source for oxytocin that binds to OXTR in the cerebral cortex.


Assuntos
Arvicolinae , Ocitocina , Receptores de Ocitocina , Animais , Ocitocina/metabolismo , Receptores de Ocitocina/metabolismo , Masculino , Feminino , Encéfalo/metabolismo , Axônios/metabolismo , Axônios/ultraestrutura , Hipotálamo/metabolismo
7.
Int J Exerc Sci ; 17(2): 576-589, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38860033

RESUMO

This study investigated the effects of biset, drop-set and traditional resistance training (RT) techniques on metabolic responses in resistance-trained males. Fifteen trained males (age 29.7 ± 6.1 years; body mass 83.4 ± 7.6 kg; RT experience 11.4 ± 6.7 years; one-repetition maximum (1RM) barbell bench press: body mass ratio 1.4 ± 0.1 a.u.) were assigned to three experimental conditions, in a randomized crossover design. The experimental conditions were bi-set (3×10 repetitions at 70%1RM in barbell bench press followed by 10 repetitions at 60%1RM in incline bench press), drop-set (3×10 repetitions at 70%1RM followed by 10 repetitions at 50%1RM in barbell bench press) and traditional RT (3×20 at 60%1RM in barbell bench press). A portable gas analyzer was used to assess energy expenditure and maximal oxygen uptake during the experimental protocols. Blood lactate levels were assessed at baseline and 1, 3, and 5 minutes after the training session. There were no differences for total training volume (p = 0.999). Post hoc comparisons revealed that bi-set elicited higher aerobic energy expenditure (p = 0.003 vs. drop-set; p < 0.001 vs. traditional RT) and aerobic oxygen consumption (p = 0.034 vs. drop-set; p < 0.001 vs. traditional RT) than other RT schemes. There were no differences regarding anaerobic EE between-conditions (p > 0.05). There was a main effect of time and condition for blood lactate levels (p < 0.001). Post hoc comparisons revealed that drop-set training elicited higher blood lactate levels than traditional RT (p = 0.009). The results suggest that RT techniques may have a potential role in optimizing metabolic responses in resistance-trained males.

8.
Nat Commun ; 14(1): 845, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792582

RESUMO

The doped perovskite BaBiO3 exhibits a maximum superconducting transition temperature (Tc) of 34 K and was the first high-Tc oxide to be discovered, yet pivotal questions regarding the nature of both the metallic and superconducting states remain unresolved. Although it is generally thought that superconductivity in the bismuthates is of the conventional s-wave type, the pairing mechanism is still debated, with strong electron-phonon coupling and bismuth valence or bond disproportionation possibly playing a role. Here we use diffuse x-ray scattering and Monte Carlo modeling to study the local structure of Ba1-xKxBiO3 across its insulator-metal boundary. We find no evidence for either long- or short-range disproportionation, which resolves a major conundrum, as disproportionation and the related polaronic effects are likely not relevant for the metallic and superconducting states. Instead, we uncover nanoscale structural correlations that break inversion symmetry, with far-reaching implications for the electronic physics. This unexpected finding furthermore establishes that the bismuthates belong to the broader classes of materials with hidden spin-orbit coupling and a tendency towards inversion-breaking displacements.

9.
Polymers (Basel) ; 15(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38139897

RESUMO

Microplastic pollution is a growing public concern as these particles are ubiquitous in various environments and can fragment into smaller nanoplastics. Another environmental concern arises from widely used engineered nanoparticles. Despite the increasing abundance of these nano-sized pollutants and the possibility of interactions with organisms at the sub cellular level, with many risks still being unknown, there are only a few publications on this topic due to the lack of reliable techniques for nanoparticle characterization. We propose a multi-technique approach for the characterization of nanoparticles down to the 10 nm level using standard micro-Raman spectroscopy combined with standard atomic force microscopy. We successfully obtained single-particle spectra from 25 nm sized polystyrene and 9 nm sized TiO2 nanoparticles with corresponding mass limits of detection of 8.6 ag (attogram) and 1.6 ag, respectively, thus demonstrating the possibility of achieving an unambiguous Raman signal from a single, small nanoparticle with a resolution comparable to more complex and time-consuming technologies such as Tip-Enhanced Raman Spectroscopy and Photo-Induced Force Microscopy.

10.
J Fungi (Basel) ; 9(7)2023 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-37504706

RESUMO

In recent years, Candida auris has emerged as a hazardous hospital-acquired pathogen. Its resistance to antifungal treatments makes it challenging, requiring new approaches to manage it effectively. Herein, we aimed to assess the impact of photodynamic inactivation mediated by methylene blue (MB-PDI) or 1,9-dimethyl MB (DMMB-PDI) combined with a red LED against C. auris. To evaluate the photoinactivation of yeasts, we quantified colony-forming units and monitored ROS production. To gain some insights into the differences between MB and DMMB, we assessed lipid peroxidation (LPO) and mitochondrial membrane potential (ΔΨm). After, we verified the effectiveness of DMMB against biofilms by measuring metabolic activity and biomass, and the structures were analyzed through scanning electron microscopy and optical coherence tomography. We also evaluated the cytotoxicity in mammalian cells. DMMB-PDI successfully eradicated C. auris yeasts at 3 µM regardless of the light dose. In contrast, MB (100 µM) killed cells only when exposed to the highest dose of light. DMMB-PDI promoted higher ROS, LPO and ΔΨm levels than those of MB. Furthermore, DMMB-PDI was able to inhibit biofilm formation and destroy mature biofilms, with no observed toxicity in fibroblasts. We conclude that DMMB-PDI holds great potential to combat the global threat posed by C. auris.

11.
Nanomaterials (Basel) ; 13(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36839111

RESUMO

Nd3+-doped GeO2-PbO glass with silver (Ag) nanoparticles (NPs) are produced with double line waveguides through fs laser processing for photonic applications. A Ti:sapphire fs laser at 800 nm was used to write the waveguides directly into the glass 0.7 mm beneath the surface. This platform is based on pairs of parallel lines with spacing of 10 µm, each pair being formed by two identical written lines but in two different configurations of 4 or 8 separately processed lines, which are coincident. The results of optical microscopy, absorbance measurements, refractive index change, beam quality factor (at 632 and 1064 nm), photoluminescence, propagation losses, and relative gain at 1064 nm are presented. The structural changes in the glass due to the presence of Ag NPs were investigated by Raman spectroscopy. At 632 and 1064 nm, x,y-symmetrical guiding was observed, and for both kinds of overlapping pulses, a refractive index alteration of 10-3 was found in both directions. Photoluminescence growth of ~47% at 1064 nm was observed due to the plasmonic effect of Ag NPs. In dual waveguides containing Ag NPs, the relative gain obtained increased by 40% and 30% for four and eight overlapping lines, respectively, at 600 mW of 808 nm pump power, when compared to waveguides without those metallic NPs. We highlight the resultant positive internal gains of 5.11 and 7.12 dB/cm that showed a growth of ~40% and ~30%, respectively, with respect to the samples without Ag NPs. The increase in photoluminescence and relative gain were related to the local field growth produced by Ag NPs. The present results show that the addition of Ag NPs impacts positively on the optical performance at 1064 nm of double line waveguides processed by fs laser writing in Nd3+-doped GeO2-PbO glass, opening news perspectives for photonics.

12.
Radiat Res ; 200(4): 366-373, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37772737

RESUMO

Radiotherapy is a well-established cancer treatment; it is estimated that approximately 52% of oncology patients will require this treatment modality at least once. However, some tumors, such as triple-negative breast cancer (TNBC), may present as radioresistant and thus require high doses of ionizing radiation and a prolonged period of treatment, which may result in more severe side effects. Moreover, such tumors show a high incidence of metastases and decreased survival expectancy of the patient. Thus, new strategies for radiosensitizing TNBC are urgently needed. Red light therapy, photobiomodulation, has been used in clinical practice to mitigate the adverse side effects usually associated with radiotherapy. However, no studies have explored its use as a radiosensitizer of TNBC. Here, we used TNBC-bearing mice as a radioresistant cancer model. Red light treatment was applied in three different protocols before a high dose of radiation (60 Gy split in 4 fractions) was administered. We evaluated tumor growth, mouse clinical signs, total blood cell counts, lung metastasis, survival, and levels of glutathione in the blood. Our data showed that the highest laser dose in combination with radiation arrested tumor progression, likely due to inhibition of GSH synthesis. In addition, red light treatment before each fraction of radiation, regardless of the light dose, improved the health status of the animals, prevented anemia, reduced metastases, and improved survival. Collectively, these results indicate that red light treatment in combination with radiation could prove useful in the treatment of TNBC.


Assuntos
Radiossensibilizantes , Neoplasias de Mama Triplo Negativas , Humanos , Animais , Camundongos , Neoplasias de Mama Triplo Negativas/radioterapia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/patologia , Modelos Animais de Doenças , Linhagem Celular Tumoral , Radiossensibilizantes/farmacologia , Luz
13.
Radiat Res ; 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37702407

RESUMO

Radiotherapy is a well-established cancer treatment; it is estimated that approximately 52% of oncology patients will require this treatment modality at least once. However, some tumors, such as triple-negative breast cancer (TNBC), may present as radioresistant and thus require high doses of ionizing radiation and a prolonged period of treatment, which may result in more severe side effects. Moreover, such tumors show a high incidence of metastases and decreased survival expectancy of the patient. Thus, new strategies for radiosensitizing TNBC are urgently needed. Red light therapy, photobiomodulation, has been used in clinical practice to mitigate the adverse side effects usually associated with radiotherapy. However, no studies have explored its use as a radiosensitizer of TNBC. Here, we used TNBC-bearing mice as a radioresistant cancer model. Red light treatment was applied in three different protocols before a high dose of radiation (60 Gy split in 4 fractions) was administered. We evaluated tumor growth, mouse clinical signs, total blood cell counts, lung metastasis, survival, and levels of glutathione in the blood. Our data showed that the highest laser dose in combination with radiation arrested tumor progression, likely due to inhibition of GSH synthesis. In addition, red light treatment before each fraction of radiation, regardless of the light dose, improved the health status of the animals, prevented anemia, reduced metastases, and improved survival. Collectively, these results indicate that red light treatment in combination with radiation could prove useful in the treatment of TNBC.

14.
Sci Rep ; 12(1): 20483, 2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36443339

RESUMO

The interplay between structural and electronic degrees of freedom in complex materials is the subject of extensive debate in physics and materials science. Particularly interesting questions pertain to the nature and extent of pre-transitional short-range order in diverse systems ranging from shape-memory alloys to unconventional superconductors, and how this microstructure affects macroscopic properties. Here we use neutron and X-ray diffuse scattering to uncover universal structural fluctuations in La2-xSrxCuO4 and Tl2Ba2CuO6+δ, two cuprate superconductors with distinct point disorder effects and with optimal superconducting transition temperatures that differ by more than a factor of two. The fluctuations are present in wide doping and temperature ranges, including compositions that maintain high average structural symmetry, and they exhibit unusual, yet simple scaling behaviour. The scaling regime is robust and universal, similar to the well-known critical fluctuations close to second-order phase transitions, but with a distinctly different physical origin. We relate this behaviour to pre-transitional phenomena in a broad class of systems with structural and magnetic transitions, and propose an explanation based on rare structural fluctuations caused by intrinsic nanoscale inhomogeneity. We also uncover parallels with superconducting fluctuations, which indicates that the underlying inhomogeneity plays an important role in cuprate physics.

15.
J Fungi (Basel) ; 8(6)2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35736039

RESUMO

Candida albicans is the main cause of superficial candidiasis. While the antifungals available are defied by biofilm formation and resistance emergence, antimicrobial photodynamic inactivation (aPDI) arises as an alternative antifungal therapy. The tetracationic metalloporphyrin Zn(II) meso-tetrakis(N-n-hexylpyridinium-2-yl)porphyrin (ZnTnHex-2-PyP4+) has high photoefficiency and improved cellular interactions. We investigated the ZnTnHex-2-PyP4+ as a photosensitizer (PS) to photoinactivate yeasts and biofilms of C. albicans strains (ATCC 10231 and ATCC 90028) using a blue light-emitting diode. The photoinactivation of yeasts was evaluated by quantifying the colony forming units. The aPDI of ATCC 90028 biofilms was assessed by the MTT assay, propidium iodide (PI) labeling, and scanning electron microscopy. Mammalian cytotoxicity was investigated in Vero cells using MTT assay. The aPDI (4.3 J/cm2) promoted eradication of yeasts at 0.8 and 1.5 µM of PS for ATCC 10231 and ATCC 90028, respectively. At 0.8 µM and same light dose, aPDI-treated biofilms showed intense PI labeling, about 89% decrease in the cell viability, and structural alterations with reduced hyphae. No considerable toxicity was observed in mammalian cells. Our results introduce the ZnTnHex-2-PyP4+ as a promising PS to photoinactivate both yeasts and biofilms of C. albicans, stimulating studies with other Candida species and resistant isolates.

16.
Front Immunol ; 13: 1019201, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36248846

RESUMO

Regulation of inflammation is a critical process for maintaining physiological homeostasis. The λ-carrageenan (λ-CGN) is a mucopolysaccharide extracted from the cell wall of red algae (Chondrus crispus) capable of inducing acute intestinal inflammation, which is translated into the production of acute phase reactants secreted into the blood circulation. However, the associated mechanisms in vertebrates are not well understood. Here, we investigated the crucial factors behind the inflammatory milieu of λ-CGN-mediated inflammation administered at 0, 1.75, and 3.5% (v/w) by i.p. injection into the peritoneal cavity of adult zebrafish (ZF) (Danio rerio). We found that polymorphonuclear leukocytes (neutrophils) and lymphocytes infiltrating the ZF peritoneal cavity had short-term persistence. Nevertheless, they generate a strong pattern of inflammation that affects systemically and is enough to produce edema in the cavity. Consistent with these findings, cell infiltration, which causes notable tissue changes, resulted in the overexpression of several acute inflammatory markers at the protein level. Using reversed-phase high-performance liquid chromatography followed by a hybrid linear ion-trap mass spectrometry shotgun proteomic approach, we identified 2938 plasma proteins among the animals injected with PBS and 3.5% λ-CGN. First, the bioinformatic analysis revealed the composition of the plasma proteome. Interestingly, 72 commonly expressed proteins were recorded among the treated and control groups, but, surprisingly, 2830 novel proteins were differentially expressed exclusively in the λ-CGN-induced group. Furthermore, from the commonly expressed proteins, compared to the control group 62 proteins got a significant (p < 0.05) upregulation in the λ-CGN-treated group, while the remaining ten proteins were downregulated. Next, we obtained the major protein-protein interaction networks between hub protein clusters in the blood plasma of the λ-CGN induced group. Moreover, to understand the molecular underpinnings of these effects based on the unveiled protein sets, we performed a bioinformatic structural similarity analysis and generated overlapping 3D reconstructions between ZF and humans during acute inflammation. Biological pathway analysis pointed to the activation and abundance of diverse classical immune and acute phase reactants, several catalytic enzymes, and varied proteins supporting the immune response. Together, this information can be used for testing and finding novel pharmacological targets to treat human intestinal inflammatory diseases.


Assuntos
Leucócitos , Proteoma , Peixe-Zebra , Proteínas de Fase Aguda , Animais , Carragenina/metabolismo , Glicosaminoglicanos , Humanos , Inflamação/induzido quimicamente , Neutrófilos/metabolismo , Plasma/metabolismo , Proteômica , Peixe-Zebra/metabolismo
17.
BMC Public Health ; 11: 674, 2011 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-21878095

RESUMO

BACKGROUND: In adults, there is a substantial body of evidence that physical inactivity or low cardiorespiratory fitness levels are strongly associated with the development of metabolic syndrome. Although this association has been studied extensively in adults, little is known regarding this association in adolescents. The aim of this study was to analyze the association between physical activity and cardiorespiratory fitness levels with metabolic syndrome in Brazilian adolescents. METHODS: A random sample of 223 girls (mean age, 14.4 ± 1.6 years) and 233 boys (mean age, 14.6 ± 1.6 years) was selected for the study. The level of physical activity was determined by the Bouchard three-day physical activity record. Cardiorespiratory fitness was estimated by the Leger 20-meter shuttle run test. The metabolic syndrome components assessed included waist circumference, blood pressure, HDL-cholesterol, triglycerides, and fasting plasma glucose levels. Independent Student t-tests were used to assess gender differences. The associations between physical activity and cardiorespiratory fitness with the presence of metabolic syndrome were calculated using logistic regression models adjusted for age and gender. RESULTS: A high prevalence of metabolic syndrome was observed in inactive adolescents (males, 11.4%; females, 7.2%) and adolescents with low cardiorespiratory fitness levels (males, 13.9%; females, 8.6%). A significant relationship existed between metabolic syndrome and low cardiorespiratory fitness (OR, 3.0 [1.13-7.94]). CONCLUSION: The prevalence of metabolic syndrome is high among adolescents who are inactive and those with low cardiorespiratory fitness. Prevention strategies for metabolic syndrome should concentrate on enhancing fitness levels early in life.


Assuntos
Doenças Cardiovasculares/epidemiologia , Exercício Físico/fisiologia , Síndrome Metabólica/epidemiologia , Aptidão Física , Adolescente , Brasil/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Atividade Motora , Prevalência , Fatores de Risco
18.
Am J Orthod Dentofacial Orthop ; 140(4): e193-8, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21967957

RESUMO

INTRODUCTION: The aim of this study was to evaluate biofilm retention around orthodontic brackets related to the method of ligation by using optical coherence tomography (OCT) and microbiologic sampling. METHODS: Seventy-five plastic central incisors for dentures were divided into 3 groups and used with metal brackets with a 0.022-in slot with elastomeric ligature (n = 25), metal brackets with a 0.022-in slot with steel wire ligature (n = 25), and self-ligating brackets with a 0.022-in slot (n = 25). The samples were submersed in a suspension of Streptococcus mutans, genetically engineered to express green fluorescent protein, at 37°C for 72 hours to allow biofilm formation. The samples were then submitted to microbiologic analysis and OCT imaging. RESULTS: The microbiologic analysis and the OCT showed significant differences in biofilm formation depending on the ligating method. Brackets ligated with elastomeric rings held more S mutans biofilm, and steel wire ligation had less biofilm retention compared with the other brackets. CONCLUSIONS: This study provided validation that OCT can be used as a potential qualitative marker of total plaque bacteria that can be rapidly and reliably visualized around orthodontic brackets.


Assuntos
Biofilmes/crescimento & desenvolvimento , Braquetes Ortodônticos/microbiologia , Tomografia de Coerência Óptica/métodos , Técnicas Bacteriológicas , Ligas Dentárias/química , Elastômeros/química , Proteínas de Fluorescência Verde , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Incisivo/microbiologia , Substâncias Luminescentes , Microscopia Confocal , Braquetes Ortodônticos/classificação , Fios Ortodônticos/microbiologia , Aço/química , Streptococcus mutans/fisiologia , Temperatura , Fatores de Tempo , Dente Artificial/microbiologia
19.
J Pharmacol Exp Ther ; 333(1): 161-73, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20086056

RESUMO

The angiotensin (Ang) IV analog norleual [Nle-Tyr-Leu-psi-(CH2-NH2)(3-4)-His-Pro-Phe] exhibits structural homology with the hinge (linker) region of hepatocyte growth factor (HGF) and is hypothesized to act as a hinge region mimic. Norleual competitively inhibited the binding of HGF to its receptor c-Met in mouse liver membranes, with an IC(50) value of 3 pM. Predictably, norleual was able to inhibit HGF-dependent signaling, proliferation, migration, and invasion in multiple cell types at concentrations in the picomolar range. Ex vivo studies demonstrated that norleual exhibited potent antiangiogenic activity, an attribute that would be predicted for a HGF/c-Met antagonist. Furthermore, norleual suppressed pulmonary colonization by B16-F10 murine melanoma cells, which are characterized by an overactive HGF/c-Met system. Together, these data suggest that AngIV analogs exert at least some of their biological activity through interference with the HGF/c-Met system and may have utility as therapeutic agents in disorders that are dependent on an intact HGF/c-Met system. Finally, the ability of norleual to induce marked biological responses in human embryonic kidney cells, which do not express insulin-responsive aminopeptidase (IRAP), coupled with the observed effects of norleual on the HGF/c-Met system, casts doubt on the physiological significance of AngIV-dependent inhibition of IRAP. [Corrected]


Assuntos
Angiotensina II/análogos & derivados , Fator de Crescimento de Hepatócito/antagonistas & inibidores , Oligopeptídeos/farmacologia , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Inibidores da Angiogênese/farmacologia , Angiotensina II/química , Animais , Linhagem Celular , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cães , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/fisiologia , Endotélio Vascular/citologia , Endotélio Vascular/efeitos dos fármacos , Ativação Enzimática , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Fator de Crescimento de Hepatócito/fisiologia , Humanos , Técnicas In Vitro , Pulmão/efeitos dos fármacos , Pulmão/patologia , Neoplasias Pulmonares/patologia , Melanoma Experimental/patologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-met/fisiologia , Ensaio Radioligante , Transdução de Sinais
20.
Nat Commun ; 10(1): 2729, 2019 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-31227719

RESUMO

A pivotal challenge posed by unconventional superconductors is to unravel how superconductivity emerges upon cooling from the generally complex normal state. Here, we use nonlinear magnetic response, a probe that is uniquely sensitive to the superconducting precursor, to uncover remarkable universal behaviour in three distinct classes of oxide superconductors: strontium titanate, strontium ruthenate, and the cuprate high-Tc materials. We find unusual exponential temperature dependence of the diamagnetic response above the transition temperature Tc, with a characteristic temperature scale that strongly varies with Tc. We correlate this scale with the sensitivity of Tc to local stress and show that it is influenced by intentionally-induced structural disorder. The universal behaviour is therefore caused by intrinsic, self-organized structural inhomogeneity, inherent to the oxides' perovskite-based structure. The prevalence of such inhomogeneity has far-reaching implications for the interpretation of electronic properties of perovskite-related oxides in general.

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