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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.
J Chem Phys ; 160(7)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38364000

RESUMO

Controlling molecular reactivity by shaped laser pulses is a long-standing goal in chemistry. Here, we suggest a direct optimal control approach that combines external pulse optimization with other control parameters arising in the upcoming field of vibro-polaritonic chemistry for enhanced controllability. The direct optimal control approach is characterized by a simultaneous simulation and optimization paradigm, meaning that the equations of motion are discretized and converted into a set of holonomic constraints for a nonlinear optimization problem given by the control functional. Compared with indirect optimal control, this procedure offers great flexibility, such as final time or Hamiltonian parameter optimization. A simultaneous direct optimal control theory will be applied to a model system describing H-atom transfer in a lossy Fabry-Pérot cavity under vibrational strong coupling conditions. Specifically, optimization of the cavity coupling strength and, thus, of the control landscape will be demonstrated.

3.
Gen Comp Endocrinol ; 354: 114519, 2024 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-38677339

RESUMO

Estrogen receptors (ERs) are thought to be the ancestor of all steroid receptors and are present in most lophotrochozoans studied to date, including molluscs, annelids, and rotifers. A number of studies have investigated the functional role of estrogen receptors in invertebrate species, although most are in molluscs, where the receptor is constitutively active. In vitro experiments provided evidence for ligand-activated estrogen receptors in annelids, raising important questions about the role of estrogen signalling in lophotrochozoan lineages. Here, we review the concordant and discordant evidence of estradiol receptor signalling in lophotrochozoans, with a focus on annelids and rotifers. We explore the de novo synthesis of estrogens, the evolution and expression of estrogen receptors, and physiological responses to activation of estrogen receptors in the lophotrochozoan phyla Annelida and Rotifera. Key data are missing to determine if de novo biosynthesis of estradiol in non-molluscan lophotrochozoans is likely. For example, an ortholog for the CYP11 gene is present, but confirmation of substrate conversion and measured tissue products is lacking. Orthologs CYP17 and CYP19 are lacking, yet intermediates or products (e.g. estradiol) in tissues have been measured. Estrogen receptors are present in multiple species, and for a limited number, in vitro data show agonist binding of estradiol and/or transcriptional activation. The expression patterns of the lophotrochozoan ERs suggest developmental, reproductive, and digestive roles but are highly species dependent. E2 exposures suggest that lophotrochozoan ERs may play a role in reproduction, but no strong dose-response relationship has been established. Therefore, we expect most lophotrochozoan species, outside of perhaps platyhelminths, to have an ER but their physiological role remains elusive. Mining genomes for orthologs gene families responsible for steroidogenesis, coupled with in vitro and in vivo studies of the steroid pathway are needed to better assess whether lophotrochozoans are capable of estradiol biosynthesis. One major challenge is that much of the data are divided across a diversity of species. We propose that the polychaetes Capitella teleta or Platyneris dumerilii, and rotifer Brachionus manjavacas may be strong species choices for studies of estrogen receptor signalling, because of available genomic data, established laboratory culture techniques, and gene knockout potential.


Assuntos
Transdução de Sinais , Animais , Transdução de Sinais/fisiologia , Transdução de Sinais/genética , Receptores de Estradiol/metabolismo , Receptores de Estradiol/genética , Anelídeos/metabolismo , Anelídeos/genética , Receptores de Estrogênio/metabolismo , Receptores de Estrogênio/genética , Rotíferos/metabolismo , Rotíferos/genética , Estradiol/metabolismo
4.
BMC Geriatr ; 24(1): 16, 2024 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-38178036

RESUMO

BACKGROUND: Hearing loss impacts health-related quality of life and general well-being and was identified in a Lancet report as one of the largest potentially modifiable factors for the prevention of age-related dementia. There is a lack of robust data on how cochlear implant treatment in the elderly impacts quality of life. The primary objective was to measure the change in health utility following cochlear implantation in individuals aged ≥ 60 years. METHODS: This study uniquely prospectively recruited a large multinational sample of 100 older adults (mean age 71.7 (SD7.6) range 60-91 years) with severe to profound hearing loss. In a repeated-measures design, pre and post implant outcome measures were analysed using mixed-effect models. Health utility was assessed with the Health Utilities Index Mark III (HUI3). Subjects were divided into groups of 60-64, 65-74 and 75 + years. RESULTS: At 18 months post implant, the mean HUI3 score improved by 0.13 (95%CI: 0.07-0.18 p < 0.001). There was no statistically significant difference in the HUI3 between age groups (F[2,9228] = 0.53, p = 0.59). The De Jong Loneliness scale reduced by an average of 0.61 (95%CI: 0.25-0.97 p < 0.014) and the Lawton Instrumental Activities of Daily Living Scale improved on average (1.25, 95%CI: 0.85-1.65 p < 0.001). Hearing Handicap Inventory for the Elderly Screening reduced by an average of 8.7 (95%CI: 6.7-10.8, p < 0.001) from a significant to mild-moderate hearing handicap. Age was not a statistically significant factor for any of the other measures (p > 0.20). At baseline 90% of participants had no or mild depression and there was no change in mean depression scores after implant. Categories of Auditory perception scale showed that all subjects achieved a level of speech sound discrimination without lip reading post implantation (level 4) and at least 50% could use the telephone with a known speaker. CONCLUSIONS: Better hearing improved individuals' quality of life, ability to communicate verbally and their ability to function independently. They felt less lonely and less handicapped by their hearing loss. Benefits were independent of age group. Cochlear implants should be considered as a routine treatment option for those over 60 years with bilateral severe to profound hearing loss. TRIAL REGISTRATION: ClinicalTrials.gov ( http://www. CLINICALTRIALS: gov/ ), 7 March 2017, NCT03072862.


Assuntos
Implante Coclear , Implantes Cocleares , Surdez , Perda Auditiva , Percepção da Fala , Idoso , Idoso de 80 Anos ou mais , Humanos , Atividades Cotidianas , Surdez/cirurgia , Perda Auditiva/diagnóstico , Perda Auditiva/terapia , Qualidade de Vida , Resultado do Tratamento , Pessoa de Meia-Idade
5.
Cryo Letters ; 45(1): 1-15, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38538367

RESUMO

The preservation of the nuclear genome's integrity is paramount for the viability and overall health of cells, tissues, and organisms. DNA, being susceptible to damage under physiological conditions and vulnerable to both endogenous and environmental factors, faces constant threats. To assess DNA damage and repair within individual eukaryotic cells, the comet assay presents itself as a versatile, gel electrophoresis-based, relatively simple, and highly sensitive method. Originally designed to monitor DNA damage and repair within populations of mammalian cells, the comet assay has now found applications across diverse domains, including yeast, protozoa, plants, and invertebrates. This technique has proven invaluable in cryopreservation studies, serving as a valuable adjunct for determining suitable cryopreservation protocols. These protocols encompass choices related to cryoprotectants, sample preparation, as well as storage conditions in terms of time and temperature. In the realm of animal cryopreservation research, the comet assay stands as a gold-standard method for assessing DNA integrity. Nevertheless, when applied in plant-oriented investigations, additional efforts are essential due to the distinct nature of plant cells and associated technical challenges. This review elucidates the fundamental principles underlying the comet assay, discusses its current iterations, and delineates its applications in the cryopreservation of both animal and plant specimens. Moreover, we delve into the primary challenges confronting the comet assay's utility as a monitoring tool in the context of plant sample cryopreservation. https://doi.org/10.54680/fr24110110112.


Assuntos
Criopreservação , Dano ao DNA , Animais , Ensaio Cometa/métodos , Criopreservação/métodos , Crioprotetores/farmacologia , DNA , Mamíferos/genética
6.
Mol Cancer ; 22(1): 112, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37454139

RESUMO

The mechanistic/mammalian target of rapamycin (mTOR), a protein discovered in 1991, integrates a complex pathway with a key role in maintaining cellular homeostasis. By comprising two functionally distinct complexes, mTOR complex 1 (mTORC1) and mTORC2, it is a central cellular hub that integrates intra- and extracellular signals of energy, nutrient, and hormone availability, modulating the molecular responses to acquire a homeostatic state through the regulation of anabolic and catabolic processes. Accordingly, dysregulation of mTOR pathway has been implicated in a variety of human diseases. While major advances have been made regarding the regulators and effectors of mTOR signaling pathway, insights into the regulation of mTOR gene expression are beginning to emerge. Here, we present the current available data regarding the mTOR expression regulation at the level of transcription, translation and mRNA stability and systematize the current knowledge about the fluctuations of mTOR expression observed in several diseases, both cancerous and non-cancerous. In addition, we discuss whether mTOR expression changes can be used as a biomarker for diagnosis, disease progression, prognosis and/or response to therapeutics. We believe that our study will contribute for the implementation of new disease biomarkers based on mTOR as it gives an exhaustive perspective about the regulation of mTOR gene expression in both normal and pathological conditions.


Assuntos
Complexos Multiproteicos , Sirolimo , Humanos , Complexos Multiproteicos/metabolismo , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/genética , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Transdução de Sinais , Alvo Mecanístico do Complexo 2 de Rapamicina/genética , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo
7.
Phys Rev Lett ; 130(9): 091903, 2023 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-36930927

RESUMO

The existence of pentaquarks with strangeness content zero and one are major discoveries of the latest years in hadron physics. Most of these states can be understood as hadronic molecules and were predicted prior to their discovery within a model based on unitarized meson-baryon amplitudes obtained from vector-meson exchange interactions. Contrary to earlier statements, we show this model to also predict the existence of pentaquarks with double strangeness, at about 4500 and 4600 MeV, which are generated in a very specific and unique mechanism, via an attraction induced by a strong coupling between the two heaviest meson-baryon states.

8.
BMC Med Ethics ; 24(1): 101, 2023 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-38007515

RESUMO

BACKGROUND: Voluntary post-mortem donation to science (PDS) is the most appropriate source for body dissection in medical education and training, and highly useful for biomedical research. In Mexico, unclaimed bodies are no longer a legal source, but PDS is legally possible, although scarcely facilitated, and mostly ignored by the general population. Therefore, we aimed to evaluate the attitude and willingness for PDS and to identify a sociodemographic profile of people with willingness toward PDS. METHODS: A validated on-line survey was distributed by the convenience method via the social networks of a Catholicism-inspired, private university in northern Mexico. Frequency analyses of all variables and coded free comments were complemented with association studies. RESULTS: Although the responder cohort (n = 143) was too small and biased to be representative of the university community (n = 13,500), willingness to post-mortem organ donation was 90.7% and to PDS 70.7%. In this cohort, PDS willingness had the strongest association with mature age (> 40 years old; P, 0.0008). Among young adults, willingness to PDS was the lowest among volunteers from technical and business schools and the highest among those from the social sciences (P, 0.009). Respondents from the social sciences were also the most consistent between attitude and behavior with respect to organ donation. A free comment option revealed respondents were interested in the unusual taboo topic. CONCLUSIONS: A small, but sufficiently large proportion expressed willingness toward PDS. In our university cohort, which was biased in higher education and altruism, mature age and social interest were associated with PDS willingness.


Assuntos
Doadores de Tecidos , Obtenção de Tecidos e Órgãos , Adulto Jovem , Humanos , Adulto , Universidades , México , Inquéritos e Questionários , Conhecimentos, Atitudes e Prática em Saúde
9.
J Intellect Disabil Res ; 67(8): 770-781, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37218112

RESUMO

BACKGROUND: The objective of this study was to evaluate the effectiveness of a 14-week resistance training programme implemented with high levels of effort to improve physical fitness in people with intellectual disabilities (IDs) living in group homes. METHODS: Fifty-two individuals with mild to moderate IDs participated in the experimental (n = 27; 15 men) or control groups (n = 25; 14 men). Participants performed 2 familiarisation sessions, 1 pretest, 42 training sessions (14 weeks × 3 sessions; only the experimental group) and 1 posttest. The testing sessions comprised the evaluation of body composition, static balance and muscle strength. The training sessions included four blocks: (1) dynamic bodyweight exercises, (2) dynamic exercises performed against external loads, (3) ballistic exercises and (4) static exercises. RESULTS: The main findings revealed that all variables related to body composition and muscle strength improved more after the intervention period in the experimental group than the control group, whereas the improvements in static balance for the experimental groups were lower than for the remaining variables used as markers of physical fitness. CONCLUSIONS: These findings highlight the importance of prescribing specific moderate-intensity to high-intensity resistance training programmes to improve body composition and muscle strength for people with IDs living in group homes.


Assuntos
Deficiência Intelectual , Treinamento Resistido , Masculino , Humanos , Lares para Grupos , Aptidão Física , Terapia por Exercício , Força Muscular/fisiologia
10.
Public Health ; 221: 97-105, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37441997

RESUMO

OBJECTIVES: Paid leave is essential for public health in order to prevent presenteeism (i.e., working while sick), provide an economic safety net for workers when ill, and promote family well-being through parental leave. While racial and ethnic disparities in unmet paid leave (or needing but not being able to take paid leave) are well documented, little evidence of the intersecting role of citizenship status exists. This study examined disparities in unmet paid leave across race, ethnicity and citizenship status. STUDY DESIGN: This was a cross-sectional study of employed adults in California, USA. METHODS: Weighted, multivariable logistic regressions were used to assess disparities in unmet needed paid leave across race, ethnicity and citizenship status categories, including non-citizen, naturalised, and citizen Latinx and Asian respondents, and naturalised and non-citizen White respondents, relative to US-born White respondents, controlling for demographic, familial, health-related and work-related covariates. This study examined a representative sample of Californian adults using the 2021 California Health Interview Survey (CHIS). A total of 24,453 people completed the CHIS from March to October 2021. This analysis was restricted to individuals who had complete data, were employed at the time of the survey and were part of the study race and ethnic groups of interest, leading to an analytical sample of 12,485 respondents. RESULTS: While 16.9% of employed Californians reported forgoing needed paid leave, disparities across race, ethnicity and citizenship status were evident. Specifically, 31.8% of non-citizen Latinx respondents, compared to 11% of US-born White respondents, did not use paid leave when they needed it due to fear of job loss, fear of negative impacts on job advancement, employers denying it, lack of information or knowledge regarding the process or ineligibility. In the fully adjusted analyses, respondents identifying as non-citizen Latinx (adjusted odds ratio [aOR] = 2.57, 95% confidence interval [CI] = 1.94-3.40), naturalised Latinx (aOR = 1.90, 95% CI = 1.46-2.48), US-born Latinx (OR = 1.30, 95% CI = 1.06-1.60), non-citizen Asian (aOR = 2.34, 95% CI = 1.69-3.23) and naturalised Asian (aOR = 1.78, 95% CI = 1.35-2.34) had a statistically significantly higher likelihood of experiencing unmet needed paid leave compared to US-born White respondents. CONCLUSIONS: Despite its importance for health, disparities across race, ethnicity and citizenship status exist in those who experience unmet paid leave. It is recommended that the administrative and enforcement agencies in California further communicate eligibility, facilitate the application process and enforce equitable access to paid leave for all workers.


Assuntos
Emprego , Etnicidade , Hispânico ou Latino , Salários e Benefícios , Adulto , Humanos , Cidadania , Estudos Transversais , Necessidades e Demandas de Serviços de Saúde , Asiático , Brancos
11.
Appl Math Model ; 121: 166-184, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37151217

RESUMO

A common basis to address the dynamics of directly transmitted infectious diseases, such as COVID-19, are compartmental (or SIR) models. SIR models typically assume homogenous population mixing, a simplification that is convenient but unrealistic. Here we validate an existing model of a scale-free fractal infection process using high-resolution data on COVID-19 spread in São Caetano, Brazil. We find that transmission can be described by a network in which each infectious individual has a small number of susceptible contacts, of the order of 2-5. This model parameter correlated tightly with physical distancing measured by mobile phone data, such that in periods of greater distancing the model recovered a lower average number of contacts, and vice versa. We show that the SIR model is a special case of our scale-free fractal process model in which the parameter that reflects population structure is set at unity, indicating homogeneous mixing. Our more general framework better explained the dynamics of COVID-19 in São Caetano, used fewer parameters than a standard SIR model and accounted for geographically localized clusters of disease. Our model requires further validation in other locations and with other directly transmitted infectious agents.

12.
Med Intensiva ; 47(5): 257-266, 2023 May.
Artigo em Espanhol | MEDLINE | ID: mdl-36506823

RESUMO

Objective: To describe the sequelae one month after hospital discharge in patients who required admission to intensive care for severe COVID-19 pneumonia and to analyze the differences between those who received therapy exclusively with high-flow oxygen therapy compared to those who required invasive mechanical ventilation. Design: Cohort, prospective and observational study. Setting: Post-intensive care multidisciplinary program. Patients or participants: Patients who survived admission to the intensive care unit (ICU) for severe COVID-19 pneumonia from April 2020 to October 2021. Interventions: Inclusion in the post-ICU multidisciplinary program. Main variables of interest: Motor, sensory, psychological/psychiatric, respiratory and nutritional sequelae after hospital admission. Results: One hundred and four patients were included. 48 patients received high-flow nasal oxygen therapy (ONAF) and 56 invasive mechanical ventilation (IMV). The main sequelae found were distal neuropathy (33.9% IMV vs. 10.4% ONAF); brachial plexopathy (10.7% IMV vs. 0% ONAF); decrease in grip strength: right hand 20.67 kg (± 8.27) in VMI vs. 31.8 kg (± 11.59) in ONAF and left hand 19.39 kg (± 8.45) in VMI vs. 30.26 kg (± 12.74) in ONAF; and limited muscle balance in the lower limbs (28.6% VMI vs. 8.6% ONAF). The differences observed between both groups did not reach statistical significance in the multivariable study. Conclusions: The results obtained after the multivariate study suggest that there are no differences in the perceived physical sequelae one month after hospital discharge depending on the respiratory therapy used, whether it was high-flow nasal oxygen therapy or prolonged mechanical ventilation, although more studies are needed to be able to draw conclusions.

13.
Neuroradiology ; 64(1): 31-42, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33974110

RESUMO

PURPOSE: The purpose of this survey was to understand the impact the Covid-19 pandemic has or has had on the work, training, and wellbeing of professionals in the field of diagnostic neuroradiology. METHODS: A survey was emailed to all ESNR members and associates as well as distributed via professional social media channels. The survey was held in the summer of 2020 when the first wave had subsided in most of Europe, while the second wave was not yet widespread. The questionnaire featured a total of 46 questions on general demographics, the various phases of the healthcare crisis, and the numbers of Covid-19 patients. RESULTS: One hundred sixty-seven responses were received from 48 countries mostly from neuroradiologists (72%). Most commonly taken measures during the crisis phase were reduction of outpatient exams (87%), reduction of number of staff present in the department (83%), reporting from home (62%), and shift work (54%). In the exit phase, these measures were less frequently applied, but reporting from home was still frequent (33%). However, only 22% had access to a fully equipped work station at home. While 81% felt safe at work during the crisis, fewer than 50% had sufficient personal protection equipment for the duration of the entire crisis. Mental wellbeing is an area of concern, with 61% feeling (much) worse than usual. Many followed online courses/congresses and considered these a viable alternative for the future. CONCLUSION: The Covid-19 pandemic substantially affected the professional life as well as personal wellbeing of neuroradiologists.


Assuntos
COVID-19 , Mídias Sociais , Adulto , Europa (Continente)/epidemiologia , Humanos , Pandemias , SARS-CoV-2
14.
Gen Comp Endocrinol ; 318: 113988, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35151726

RESUMO

In southeast Asia, males of the Siamese fighting fish, Betta splendens, have been selected across centuries for winning paired staged fights and previous work has shown that males from fighter strains are more aggressive than wild-types. This strong directional selection for winners is likely to have targeted aggression-related endocrine systems, and a comparison between fighter and wild-type strains can bring into evidence the key hormones implicated in aggression. Here, we compared the plasma levels of the androgen 11-ketotestosterone (KT) and of the corticosteroid cortisol (F) in F2 males of a fighter and a wild-type strain raised under similar laboratory conditions. We show that F was generally lower in fighter as compared with wild-type males, while no overall differences in KT levels were detected between strains. When presented with a mirror-induced aggressive challenge, post-fight levels of F increased but more significantly so in wild-type males, while KT increased in males of both strains. After the challenge, fighter males had higher levels of KT as compared with wild-type males, while the pattern for F was opposite. As compared with animals in social groups, wild-type males placed under social isolation had lower F levels, while KT decreased for fighters. Taken together, this data suggests that while wild-type males responded to aggression with an increase in circulating levels of both androgens and corticosteroids, males selected for winning fights maintained a blunt F response, increasing only KT levels. These data agree with the hypothesis that a combination of high levels of androgens and low levels of corticosteroids is associated with high aggression. Overall, these results seem to indicate that selection for winning had a stronger impact in the hypothalamus-pituitary-interrenal axis than in the hypothalamus-pituitary-gonadal axis in B. splendens.


Assuntos
Androgênios , Peixes , Corticosteroides , Androgênios/fisiologia , Animais , Sistema Endócrino , Hidrocortisona , Masculino
15.
Appl Opt ; 61(16): 4908-4918, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36255976

RESUMO

We study the impact of the loss of axial symmetry around the optical axis on the polarimetric properties of a telescope with a segmented primary mirror when each segment is present in a different aging stage. The different oxidation stage of each segment as it is substituted in time leads to nonnegligible cross-talk terms. This effect is wavelength dependent, and it is mainly determined by the properties of the reflecting material. For an aluminum coating, the worst polarimetric behavior due to oxidation is found for the blue part of the visible. Contrarily, dust-as modeled in this work-does not significantly change the polarimetric behavior of the optical system. Depending on the telescope, there might be segment substitution sequences that strongly attenuate this instrumental polarization.

16.
Cryo Letters ; 43(6): 357-367, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36629831

RESUMO

BACKGROUND: Non-surgical artificial insemination techniques for sheep may benefit from larger numbers of sperm in the insemination dose because the ewe cervix is convoluted and often cannot be traversed with an insemination gun resulting in deposition of the sperm at the os cervix. OBJECTIVE: To compare a range of sperm concentrations when cryopreserving semen from Santa Ines rams and determine the effects of this on post-thaw quality. MATERIALS AND METHODS: One ejaculate from each ram (n = 10) was diluted to four sperm concentrations to obtain the following groups: G-400, G-800, G-1200, and G-1600 x 106 sperm/mL. The semen samples were packaged in 0.25 mL straws, cooled to 5 degree C, cryopreserved in liquid nitrogen vapor, thawed in a water bath (40 degree C per 20 s), and were analyzed for computerized kinetics, capacitation and acrosome integrity, and plasma membrane integrity of sperm. RESULTS: The G-400 treatment resulted in samples with the highest linearity and progressive motion (P < 0.05) and had significantly greater plasma membrane integrity, and lower capacitation and acrosome reaction rates compared to G-1600 (P < 0.05). Overall, use of the G-400 treatment resulted in better kinetics, less plasma membrane damage and less early capacitation. However, despite reducing the ejaculate yield and increasing the costs of the semen freezing process, the G-800 and G-1200 treatments make a greater absolute number of sperm with good kinetics, plasma membrane integrity and capacitation status available. CONCLUSION: Ram sperm concentration impacts cryopreservation, and higher concentrations may be advantageous if a single artificial insemination protocol is desirable. doi.org/10.54680/fr22610110812.


Assuntos
Criopreservação , Preservação do Sêmen , Feminino , Masculino , Ovinos , Animais , Criopreservação/veterinária , Criopreservação/métodos , Sêmen , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides , Espermatozoides , Carneiro Doméstico
17.
Int J Environ Health Res ; 32(10): 2271-2285, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34348544

RESUMO

Mycotoxins have several toxicological implications. In the present study, we evaluate the presence of aflatoxin B1 (AFB1), ochratoxin A (OTA), and fumonisin (FB1) in paddy rice, polished rice, and maize from the fields and markets in Nayarit State (Mexico). The results indicated the presence of AFB1 in 21.21% of paddy rice samples and 11.11% of market maize samples. OTA was present in only 3.03% (one sample) of paddy rice samples. FB1 was detected in 87.50% and 88.88% of maize samples from field and market, respectively. The estimated human exposure was calculated for FB1 using the probable daily intake (PDI), which suggested that FB1 could contribute to the development of diseases through the consumption of contaminated maize. Positive samples indicated that some rice and maize samples were not suitable for human consumption. Further efforts are needed to continue monitoring mycotoxins and update national legislation on mycotoxins accordingly.


Assuntos
Fumonisinas , Micotoxinas , Oryza , Aflatoxina B1/análise , Grão Comestível/química , Contaminação de Alimentos/análise , Fumonisinas/análise , Humanos , México , Micotoxinas/análise , Zea mays
18.
Platelets ; 32(5): 697-700, 2021 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-32664776

RESUMO

Identification of qualitative variants of von Willebrand disease (VWD) can be a diagnostic challenge because of discrepant results obtained in the multiple laboratory tests available for its appropriate classification. We report two cases of infrequent inherited variants of VWD with unclear preliminary results with the test panel available at the time of first consultation and that were finally diagnosed as a VWD type 2A/IID with a c.8318 G > C, p.Cys2773Ser mutation and a VWD type 2M with c.4225 T > G, p.Val1409Phe mutation, respectively. The description of these two cases highlights that despite the limited diagnostic panel for the evaluation of von Willebrand Factor (VWF) functionality, the multimeric analysis and genetic family studies were fundamental tools to achieve the final diagnosis.


Assuntos
Doenças de von Willebrand/diagnóstico , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Adulto Jovem
19.
Aging Clin Exp Res ; 33(4): 759-773, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33742387

RESUMO

Osteoporosis, a common chronic metabolic bone disease is associated with considerable morbidity and mortality. As the prevalence of osteoporosis increases with age, a paralleled elevation in the rate of incident fragility fractures will be observed. This narrative review explores the origins of bone and considers physiological mechanisms involved in bone homeostasis relevant to management and treatment. Secondary causes of osteoporosis, as well as osteosarcopenia are discussed followed by an overview of the commonly used pharmacological treatments for osteoporosis in older people.


Assuntos
Doenças Ósseas Metabólicas , Fraturas Ósseas , Osteoporose , Sarcopenia , Idoso , Idoso de 80 Anos ou mais , Humanos , Osteoporose/tratamento farmacológico , Prevalência
20.
Physica D ; 421: 132839, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33424064

RESUMO

Since the start of the COVID-19 pandemic in China many models have appeared in the literature, trying to simulate its dynamics. Focusing on modeling the biological and sociological mechanisms which influence the disease spread, the basic reference example is the SIR model. However, it is too simple to be able to model those mechanisms (including the three main types of control measures: social distancing, contact tracing and health system measures) to fit real data and to simulate possible future scenarios. A question, then, arises: how much and how do we need to complexify a SIR model? We develop a θ -SEIHQRD model, which may be the simplest one satisfying the mentioned requirements for arbitrary territories and can be simplified in particular cases. We show its very good performance in the Italian case and study different future scenarios.

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