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1.
Cochrane Database Syst Rev ; 7: CD015573, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38994714

RESUMO

BACKGROUND: Cystic echinococcosis is a parasitic infection mainly impacting people living in low- and middle-income countries. Infection may lead to cyst development within organs, pain, non-specific symptoms or complications including abscesses and cyst rupture. Treatment can be difficult and varies by country. Treatments include oral medication, percutaneous techniques and surgery. One Cochrane review previously assessed the benefits and harms of percutaneous treatment compared with other treatments. However, evidence for oral medication, percutaneous techniques and surgery in specific cyst stages has not been systematically investigated and the optimal choice remains uncertain. OBJECTIVES: To assess the benefits and harms of medication, percutaneous and surgical interventions for treating uncomplicated hepatic cystic echinococcosis. SEARCH METHODS: We searched CENTRAL, MEDLINE, two other databases and two trial registries to 4 May 2023. We searched the reference lists of included studies, and contacted experts and researchers in the field for relevant studies. SELECTION CRITERIA: We included randomized controlled trials (RCTs) in people with a diagnosis of uncomplicated hepatic cystic echinococcosis of World Health Organization (WHO) cyst stage CE1, CE2, CE3a or CE3b comparing either oral medication (albendazole) to albendazole plus percutaneous interventions, or to surgery plus albendazole. Studies comparing praziquantel plus albendazole to albendazole alone prior to or following an invasive intervention (surgery or percutaneous treatment) were eligible for inclusion. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were symptom improvement, recurrence, inactive cyst at 12 months and all-cause mortality at 30 days. Our secondary outcomes were development of secondary echinococcosis, complications of treatment and duration of hospital stay. We used GRADE to assess the certainty of evidence. MAIN RESULTS: We included three RCTs with 180 adults and children with hepatic cystic echinococcosis. Two studies enrolled people aged 5 to 72 years, and one study enrolled children aged 6 to 14 years. One study compared standard catheterization plus albendazole with puncture, aspiration, injection and re-aspiration (PAIR) plus albendazole, and two studies compared laparoscopic surgery plus albendazole with open surgery plus albendazole. The three RCTs were published between 2020 and 2022 and conducted in India, Pakistan and Turkey. There were no other comparisons. Standard catheterization plus albendazole versus PAIR plus albendazole The cyst stages were CE1 and CE3a. The evidence is very uncertain about the effect of standard catheterization plus albendazole compared with PAIR plus albendazole on cyst recurrence (risk ratio (RR) 3.67, 95% confidence interval (CI) 0.16 to 84.66; 1 study, 38 participants; very low-certainty evidence). The evidence is very uncertain about the effects of standard catheterization plus albendazole on 30-day all-cause mortality and development of secondary echinococcosis compared to open surgery plus albendazole. There were no cases of mortality at 30 days or secondary echinococcosis (1 study, 38 participants; very low-certainty evidence). Major complications were reported by cyst and not by participant. Standard catheterization plus albendazole may increase major cyst complications compared with PAIR plus albendazole, but the evidence is very uncertain (RR 10.74, 95% CI 1.39 to 82.67; 1 study, 53 cysts; very low-certainty evidence). Standard catheterization plus albendazole may make little to no difference on minor complications compared with PAIR plus albendazole, but the evidence is very uncertain (RR 1.03, 95% CI 0.60 to 1.77; 1 study, 38 participants; very low-certainty evidence). Standard catheterization plus albendazole may increase the median duration of hospital stay compared with PAIR plus albendazole, but the evidence is very uncertain (4 (range 1 to 52) days versus 1 (range 1 to 15) days; 1 study, 38 participants; very low-certainty evidence). Symptom improvement and inactive cysts at 12 months were not reported. Laparoscopic surgery plus albendazole versus open surgery plus albendazole The cyst stages were CE1, CE2, CE3a and CE3b. The evidence is very uncertain about the effect of laparoscopic surgery plus albendazole on cyst recurrence in participants with CE2 and CE3b cysts compared to open surgery plus albendazole (RR 3.00, 95% CI 0.13 to 71.56; 1 study, 82 participants; very low-certainty evidence). The second study involving 60 participants with CE1, CE2 or CE3a cysts reported no recurrence in either group. The evidence is very uncertain about the effect of laparoscopic surgery plus albendazole on 30-day all-cause mortality in participants with CE1, CE2, CE3a or CE3b cysts compared to open surgery plus albendazole. There was no mortality in either group (2 studies, 142 participants; very low-certainty evidence). The evidence is very uncertain about the effect of laparoscopic surgery plus albendazole on major complications in participants with CE1, CE2, CE3a or CE3b cysts compared to open surgery plus albendazole (RR 0.50, 95% CI 0.13 to 1.92; 2 studies, 142 participants; very low-certainty evidence). Laparoscopic surgery plus albendazole may lead to slightly fewer minor complications in participants with CE1, CE2, CE3a or CE3b cysts compared to open surgery plus albendazole (RR 0.13, 95% CI 0.02 to 0.98; 2 studies, 142 participants; low-certainty evidence). Laparoscopic surgery plus albendazole may reduce the duration of hospital stay compared with open surgery plus albendazole (mean difference (MD) -1.90 days, 95% CI -2.99 to -0.82; 2 studies, 142 participants; low-certainty evidence). Symptom improvement, inactive cyst at 12 months and development of secondary echinococcosis were not reported. AUTHORS' CONCLUSIONS: Percutaneous and surgical interventions combined with albendazole can be used to treat uncomplicated hepatic cystic echinococcosis; however, there is a scarcity of randomised evidence directly comparing these interventions. There is very low-certainty evidence to indicate that standard catheterization plus albendazole may lead to fewer cases of recurrence, more major complications and similar complication rates compared to PAIR plus albendazole in adults and children with CE1 and CE3a cysts. There is very low-certainty evidence to indicate that laparoscopic surgery plus albendazole may result in fewer cases of recurrence or fewer major complications compared to open surgery plus albendazole in adults and children with CE1, CE2, CE3a and CE3b cysts. Laparoscopic surgery plus albendazole may lead to slightly fewer minor complications. Firm conclusions cannot be drawn due to the limited number of studies, small sample size and lack of events for some outcomes.


Assuntos
Albendazol , Equinococose Hepática , Praziquantel , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Albendazol/uso terapêutico , Equinococose Hepática/terapia , Equinococose Hepática/cirurgia , Equinococose Hepática/complicações , Praziquantel/uso terapêutico , Adulto , Anti-Helmínticos/uso terapêutico , Criança , Pessoa de Meia-Idade , Recidiva , Anticestoides/uso terapêutico , Adolescente , Viés , Terapia Combinada/métodos
2.
Artigo em Inglês | MEDLINE | ID: mdl-38876440

RESUMO

The swimming activity, although an essential trait in the life cycle of fish, is still poorly understood in farmed fish. The current study aimed to investigate the impact of short-term induced swimming on the immune and antioxidant defence systems in European eel (Anguilla anguilla). Sixteen male yellow European eels (total length: 39.9 ± 0.7 cm; body weight: 108.8 ± 6.1 g) were individually placed in swimming flumes and divided into two groups: i) no swimming (n = 8); and ii) induced-swimming (n = 8) at 0.3 body lengths (BL)·s-1 for 7 h. Swimming resulted in a 2-fold lower cortisol concentration in plasma, whereas plasma glucose, lactate, and several immune-related parameters did not present variations between groups. Interestingly, swimming led to higher lysozyme, peroxidase, and protease activities in skin mucus, whereas bactericidal activity did not show differences among groups. Additionally, the gene expression of interleukin 1 beta showed an up-regulation in the skin of fish with induced swimming, while no differences were observed in the head-kidney or gills. Furthermore, modulation of the antioxidant status was observed in the liver and posterior skeletal muscle after induced swimming. Fish subjected to swimming showed lower lipid peroxidation and higher reduced glutathione levels, increasing the reduced/oxidized glutathione ratio. However, no variations in the antioxidant status were observed between groups in the anterior skeletal muscle. This study showed modulation of immune and oxidative stress markers in European eels upon short-term induced swimming compared to non-swimming fish.

3.
Rhinology ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598348

RESUMO

BACKGROUND: Although there are several endoscopic grading systems for chronic rhinosinusitis (CRS), they are limited in their range and applicability. We developed a SiNonasal Endoscopic Score (SiNES) that builds upon the strengths of previous systems while addressing their limitations. METHODS: The SiNES system was developed by consensus after multiple rounds of guided discussions. Face, content, and convergent validity were investigated. It was validated using an independent sample of 79 CRS individuals from two referral centres from September 2021 to February 2022. Each patient underwent a sinonasal endoscopy and filled PROM questionnaires. Three independent rhinologists graded endoscopic videos using the SiNES and modified Lund-Kennedy (MLK) scores. Inter-rater and test-retest reliability were assessed via the intraclass correlation coefficient (ICC). SiNES and MLK scores were correlated with PROMs using a Spearman correlation and canonical correlation analysis (CCA). RESULTS: The SiNES system evaluates five anatomical spaces regarding edema, discharge, and scarring. Face, content, and convergent validity were deemed satisfactory by the study authors and an independent panel of Otolaryngologists. Inter-rater reliability was excellent for the SiNES and good for the MLK score. Test-retest reliability was excellent for both systems. Total SiNES was correlated with self-reported smell loss. CONCLUSIONS: The SiNES system is an accurate and reliable grading framework applicable to all CRS subtypes. It can be utilized in clinical and research settings and improves upon previously published systems.

4.
J Fish Biol ; 105(1): 358-371, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38802981

RESUMO

Changes in body shape are linked to swimming performance and become relevant for selective breeding programmes in cultured finfish. We studied how the selection for fast growth could affect phenotypes by investigating the relationship between swimming performance and body shape. We also investigated how swimming might affect plasma metabolite concentrations. Critical swimming speed (UCrit), body traits (e.g., BW, body weight; BL, body length; K, condition factor), and plasma lactate and glucose concentrations were evaluated in two cohorts of Australasian snapper (Chrysophrys auratus): one derived from wild broodstock (F1), and the other selected for fast growth (F4). UCrit tests (n = 8) were applied in groups of 10 snapper of similar BW (71.7 g) and BL (14.6 cm). The absolute or relative UCrit values of both cohorts were similar (0.702 m⋅s-1 and 4.795 BL⋅s-1, respectively), despite the F4 cohort displaying a higher K. A positive correlation between K and absolute UCrit (Pearson's r = 0.414) was detected in the F4 cohort, but not in the F1 cohort, which may be linked to differences in body shape. A negative correlation between relative UCrit and body size (Pearson's r between -0.682 and -0.501), but no correlation between absolute UCrit and body size, was displayed in both cohorts. Plasma lactate and glucose concentrations were higher in the F4 cohort at UCrit. Whether a longer selective breeding programme could result in more changes in body shape, potentially affecting swimming performance, should be explored, along with the potential outcomes of the differences in metabolic traits detected.


Assuntos
Glicemia , Ácido Láctico , Natação , Animais , Natação/fisiologia , Ácido Láctico/sangue , Glicemia/análise , Perciformes/crescimento & desenvolvimento , Perciformes/fisiologia , Perciformes/anatomia & histologia , Fenótipo , Peso Corporal , Tamanho Corporal , Seleção Genética , Masculino , Feminino
5.
Artigo em Inglês | MEDLINE | ID: mdl-33649109

RESUMO

Cerebral malaria (CM) is a severe immunovasculopathy which presents high mortality rate (15-20%), despite the availability of artemisinin-based therapy. More effective immunomodulatory and/or antiparasitic therapies are urgently needed. Experimental Cerebral Malaria (ECM) in mice is used to elucidate aspects involved in this pathology since manifests many of the neurological features of CM. In the present study, we evaluated the potential mechanisms involved in the protection afforded by perillyl alcohol (POH) in mouse strains susceptible to CM caused by Plasmodium berghei ANKA (PbA) infection through intranasal preventive treatment. Additionally, to evaluate the interaction of POH with the cerebral endothelium using an in vitro model of human brain endothelial cells (HBEC). Pharmacokinetic approaches demonstrated constant and prolonged levels of POH in the plasma and brain after a single intranasal dose. Treatment with POH effectively prevented vascular dysfunction. Furthermore, treatment with POH reduced the endothelial cell permeability and PbA s in the brain and spleen. Finally, POH treatment decreased the accumulation of macrophages and T and B cells in the spleen and downregulated the expression of endothelial adhesion molecules (ICAM-1, VCAM-1, and CD36) in the brain. POH is a potent monoterpene that prevents cerebrovascular dysfunction in vivo and in vitro, decreases parasite sequestration, and modulates different processes related to the activation, permeability, and integrity of the blood brain barrier (BBB), thereby preventing cerebral oedema and inflammatory infiltrates.

6.
Curr Allergy Asthma Rep ; 23(12): 715-731, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38038879

RESUMO

PURPOSE OF REVIEW: To review the effects of endoscopic sinus surgery and endonasal approaches to the skull base on olfaction. RECENT FINDINGS: Advancements in endonasal endoscopic approaches to the sinuses and skull base allow for direct treatment of a variety of sinonasal and skull base diseases. However, these extended approaches will often require manipulation of normal anatomical structures and the olfactory neuroepithelium. Depending on the planned procedure and extent of disease, the prognosis of olfactory perception can vary significantly among patients. Endoscopic sinonasal surgical procedures may impact olfaction. Optimizing olfactory function requires proper surgical techniques, gentle handling of tissue, and perioperative care. Surgeons must discuss objectives and manage patient expectations. Routine olfactory assessment is crucial in surgical work-up and follow-up. Preserving anatomical structures while addressing the obstruction of the olfactory cleft helps to prevent decreased olfactory threshold. However, smell identification and discrimination do not always correlate with sinonasal anatomy.


Assuntos
Endoscopia , Seios Paranasais , Humanos , Endoscopia/efeitos adversos , Endoscopia/métodos , Seios Paranasais/cirurgia , Olfato , Nariz , Base do Crânio/cirurgia
7.
Arch Virol ; 168(2): 74, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36683075

RESUMO

This article summarises the activities of the Bacterial Viruses Subcommittee of the International Committee on Taxonomy of Viruses for the period of March 2021-March 2022. We provide an overview of the new taxa proposed in 2021, approved by the Executive Committee, and ratified by vote in 2022. Significant changes to the taxonomy of bacterial viruses were introduced: the paraphyletic morphological families Podoviridae, Siphoviridae, and Myoviridae as well as the order Caudovirales were abolished, and a binomial system of nomenclature for species was established. In addition, one order, 22 families, 30 subfamilies, 321 genera, and 862 species were newly created, promoted, or moved.


Assuntos
Bacteriófagos , Caudovirales , Siphoviridae , Vírus , Humanos , Vírus/genética , Myoviridae
8.
J Phys Chem A ; 127(14): 3114-3122, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-37010238

RESUMO

Many years ago, the gas-phase infrared fundamental intensities of Cl2CS were determined within experimental error from the experimental intensities and frequencies of F2CO, Cl2CO, and F2CS. An additive characteristic substituent shift relationship between atomic polar tensors of these molecules formed the basis for these calculations. Here, QCISD/cc-pVTZ-level Quantum Theory of Atoms In Molecules (QTAIM) individual charge, charge transfer, and polarization contributions to these atomic polar tensor elements are shown to obey the same basic relationship for the extended X2CY (Y = O, S; X = H, F, Cl, Br) family of molecules. QTAIM charge and polarization contributions, as well as the total equilibrium dipole moments of the X2CY molecules, also follow this characteristic substituent shift model. The root-mean-sqaure error for the 231 estimates of these parameters is 0.14 e or only about 1% of the total 10 e range of the Atomic Polar Tensor (APT) contributions determined from the wave functions. The substituent effect APT contribution estimates were used to calculate the infrared intensities of the X2CY molecules. Although one serious discrepancy was observed for one of the CH stretching vibrations of H2CS, accurate values were within 45 km·mol-1 or about 7% of the 656 km·mol-1 intensity range predicted by the QCISD/cc-pVTZ wave functions. Hirshfeld charge, charge transfer, and polarization contributions are also found to follow this model, although their charge parameters do not follow electronegativity expectations.

9.
Artigo em Inglês | MEDLINE | ID: mdl-37437802

RESUMO

Aerobic swimming exercise in fish has been shown to improve robustness of some species. However, the optimal conditions to be applied and the mechanisms underlying remain unknown. We investigated the effects of 6 h of induced swimming on the immune response of gilthead seabream (Sparus aurata), by analysing markers related to immune status in plasma, skin mucus, gills, heart and head-kidney. Forty fish were individually exercised in swim tunnels by applying different water currents: steady low (SL, 0.8 body lengths (BL) s-1), steady high (SH, 2.3 BL s-1), oscillating low (OL, 0.2/0.8 BL s-1) and oscillating high (OH, 0.8/2.3 BL s-1) velocities, including a non-exercised group with minimal water flow (MF, <0.1 BL s-1). Swimming conditions did not trigger a stress response or anaerobic metabolism, suggested by similar levels of cortisol, lactate, and glucose in plasma among groups. Blood haemoglobin and innate immune parameters in plasma and skin mucus also remained unaltered. However, decreased blood haematocrit was observed in fish swimming on the OL condition. Interestingly, gene expression analysis revealed that the OL condition led to the up-regulation of pro-inflammatory mediators (nfκb1 and mapk3) and cytokines (tnfα, il1ß and il6) in gills. A similar response occurred in heart, with an up-regulation of nfκb1, tnfα, il6 and cox2 in the OL condition. Gene expression of these cytokines was unaltered in the head-kidney. The inflammatory response in gills and heart of gilthead seabream triggered by the OL condition highlights the importance of establishing suitable rearing conditions to improve welfare of cultured fish.


Assuntos
Dourada , Animais , Dourada/metabolismo , Citocinas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Natação , Interleucina-6/metabolismo , Água/metabolismo
10.
BMC Biol ; 20(1): 228, 2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-36209095

RESUMO

BACKGROUND: One-carbon metabolism, which includes the folate and methionine cycles, involves the transfer of methyl groups which are then utilised as a part of multiple physiological processes including redox defence. During the methionine cycle, the vitamin B12-dependent enzyme methionine synthetase converts homocysteine to methionine. The enzyme S-adenosylmethionine (SAM) synthetase then uses methionine in the production of the reactive methyl carrier SAM. SAM-binding methyltransferases then utilise SAM as a cofactor to methylate proteins, small molecules, lipids, and nucleic acids. RESULTS: We describe a novel SAM methyltransferase, RIPS-1, which was the single gene identified from forward genetic screens in Caenorhabditis elegans looking for resistance to lethal concentrations of the thiol-reducing agent dithiothreitol (DTT). As well as RIPS-1 mutation, we show that in wild-type worms, DTT toxicity can be overcome by modulating vitamin B12 levels, either by using growth media and/or bacterial food that provide higher levels of vitamin B12 or by vitamin B12 supplementation. We show that active methionine synthetase is required for vitamin B12-mediated DTT resistance in wild types but is not required for resistance resulting from RIPS-1 mutation and that susceptibility to DTT is partially suppressed by methionine supplementation. A targeted RNAi modifier screen identified the mitochondrial enzyme methylmalonyl-CoA epimerase as a strong genetic enhancer of DTT resistance in a RIPS-1 mutant. We show that RIPS-1 is expressed in the intestinal and hypodermal tissues of the nematode and that treating with DTT, ß-mercaptoethanol, or hydrogen sulfide induces RIPS-1 expression. We demonstrate that RIPS-1 expression is controlled by the hypoxia-inducible factor pathway and that homologues of RIPS-1 are found in a small subset of eukaryotes and bacteria, many of which can adapt to fluctuations in environmental oxygen levels. CONCLUSIONS: This work highlights the central importance of dietary vitamin B12 in normal metabolic processes in C. elegans, defines a new role for this vitamin in countering reductive stress, and identifies RIPS-1 as a novel methyltransferase in the methionine cycle.


Assuntos
Sulfeto de Hidrogênio , Ácidos Nucleicos , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/metabolismo , Animais , Caenorhabditis elegans/metabolismo , Carbono/metabolismo , Ditiotreitol/metabolismo , Ácido Fólico/metabolismo , Homocisteína/metabolismo , Sulfeto de Hidrogênio/metabolismo , Ligases/metabolismo , Lipídeos , Mercaptoetanol/metabolismo , Metionina/metabolismo , Metiltransferases/genética , Metiltransferases/metabolismo , Oxigênio/metabolismo , Substâncias Redutoras/metabolismo , S-Adenosilmetionina/metabolismo , Compostos de Sulfidrila/metabolismo , Vitamina B 12/metabolismo , Vitamina B 12/farmacologia , Vitaminas/metabolismo
11.
Int J Mol Sci ; 24(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37047078

RESUMO

Although the exact mechanism of the pathogenesis of coronavirus SARS-CoV-2 (COVID-19) is not fully understood, oxidative stress and the release of pro-inflammatory cytokines have been highlighted as playing a vital role in the pathogenesis of the disease. In this sense, alternative treatments are needed to reduce the level of inflammation caused by COVID-19. Therefore, this study aimed to investigate the potential effect of red photobiomodulation (PBM) as an attractive therapy to downregulate the cytokine storm caused by COVID-19 in a zebrafish model. RT-qPCR analyses and protein-protein interaction prediction among SARS-CoV-2 and Danio rerio proteins showed that recombinant Spike protein (rSpike) was responsible for generating systemic inflammatory processes with significantly increased levels of pro-inflammatory (il1b, il6, tnfa, and nfkbiab), oxidative stress (romo1) and energy metabolism (slc2a1a and coa1) mRNA markers, with a pattern similar to those observed in COVID-19 cases in humans. On the other hand, PBM treatment was able to decrease the mRNA levels of these pro-inflammatory and oxidative stress markers compared with rSpike in various tissues, promoting an anti-inflammatory response. Conversely, PBM promotes cellular and tissue repair of injured tissues and significantly increases the survival rate of rSpike-inoculated individuals. Additionally, metabolomics analysis showed that the most-impacted metabolic pathways between PBM and the rSpike treated groups were related to steroid metabolism, immune system, and lipid metabolism. Together, our findings suggest that the inflammatory process is an incisive feature of COVID-19 and red PBM can be used as a novel therapeutic agent for COVID-19 by regulating the inflammatory response. Nevertheless, the need for more clinical trials remains, and there is a significant gap to overcome before clinical trials can commence.


Assuntos
COVID-19 , Animais , Humanos , Peixe-Zebra/metabolismo , SARS-CoV-2/metabolismo , Síndrome da Liberação de Citocina , Citocinas/metabolismo , RNA Mensageiro , Proteínas de Membrana , Proteínas Mitocondriais
12.
Phys Chem Chem Phys ; 24(18): 11278-11294, 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35481948

RESUMO

Understanding and controlling polymorphism in molecular solids is a major unsolved problem in crystal engineering. While the ability to calculate accurate lattice energies with atomistic modelling provides valuable insight into the associated energy scales, existing methods cannot connect energy differences to the delicate balances of intra- and intermolecular forces that ultimately determine polymorph stability ordering. We report herein a protocol for applying Quantum Chemical Topology (QCT) to study the key intra- and intermolecular interactions in molecular solids, which we use to compare the three known polymorphs of succinic acid including the recently-discovered γ form. QCT provides a rigorous partitioning of the total energy into contributions associated with topological atoms, and a quantitative and chemically intuitive description of the intra- and intermolecular interactions. The newly-proposed Relative Energy Gradient (REG) method ranks atomistic energy terms (steric, electrostatic and exchange) by their importance in constructing the total energy profile for a chemical process. We find that the conformation of the succinic acid molecule is governed by a balance of large and opposing electrostatic interactions, while the H-bond dimerisation is governed by a combination of electrostatics and sterics. In the solids, an atomistic energy balance emerges that governs the contraction, towards the equilibrium geometry, of a molecular cluster representing the bulk crystal. The protocol we put forward is as general as the capabilities of the underlying quantum-mechanical model and it can provide novel perspectives on polymorphism in a wide range of chemical systems.

13.
J Phys Chem A ; 126(48): 8945-8954, 2022 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-36417362

RESUMO

The Interacting Quantum Atoms (IQA) energy decomposition scheme divides the total energy of a molecule into intra- and interatomic contributions. While the former relates to the kinetic and potential energies of electrons inside a unique individual atomic basin, the latter contains the Coulomb and exchange-correlation potentials between electrons from two atomic basins. Considering that the molecular energy is a sum of IQA contributions, the Hessian matrix can also be written as a sum of "IQA Hessian" matrices, whose elements are second derivatives of IQA terms. Herein, we present a mathematical formalism for the IQA decomposition of force constants revealing their energetic origins. The method consists of adding a new dimension to the Hessian matrix, which becomes 3N × 3N × N2, with N being the number of atoms in the molecule and N2 the number of IQA terms. Since there is no analytical method that produces the IQA second derivatives, the three-dimensional IQA Hessian is numerically calculated. When studying molecular vibrations, force constants, providing information about the nature of chemical bond and related to infrared frequencies, can be obtained by Wilson's FG method, which involves detailed manipulations of the Hessian matrix. In this paper, the methodology is reported and validated for a set of 30 molecules and more than 200 force constants and their interactions. Energetic origins of force constants are presented for diatomics and small molecules containing carbon-carbon, oxygen-oxygen, and carbon-oxygen bonds with different bond orders. It is found that bond stability and stiffness can have strikingly different energetic origins.

14.
Health Care Manag Sci ; 25(1): 146-165, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34453651

RESUMO

During the current COVID-19 pandemic, active testing has risen as a key component of many response strategies around the globe. Such strategies have a common denominator: the limited availability of diagnostic tests. In this context, pool testing strategies have emerged as a means to increase testing capacity. The efficiency gains obtained by using pool testing, derived from testing combined samples simultaneously, vary according to the spread of the SARS-CoV-2 virus in the population being tested. Motivated by the need for testing closed populations, such as long-term care facilities (LTCFs), where significant correlation in infections is expected, we develop a probabilistic model for settings where the test results are correlated, which we use to compute optimal pool sizes in the context of two-stage pool testing schemes. The proposed model incorporates the specificity and sensitivity of the test, which makes it possible to study the impact of these measures on both the expected number of tests required for diagnosing a population and the expected number and variance of false negatives. We use our experience implementing pool testing in LTCFs managed by SENAMA (Chile's National Service for the Elderly) to develop a simulation model of contagion dynamics inside LTCFs, which incorporates testing and quarantine policies implemented by SENAMA. We use this simulation to estimate the correlation of test results among collected samples when following SENAMA's testing guidelines. Our results show that correlation estimates are high in settings representative of LTCFs, which validates the use of the proposed model for incorporating correlation in determining optimal pool sizes for pool testing strategies. Generally, our results show that settings in which pool testing achieves efficiency gains, relative to individual testing, are likely to be found in practice. Moreover, the results show that incorporating correlation in the analysis of pool testing strategies both improves the expected efficiency and broadens the settings in which the technique is preferred over individual testing.


Assuntos
COVID-19 , Idoso , COVID-19/diagnóstico , Humanos , Modelos Estatísticos , Pandemias , SARS-CoV-2
15.
BMC Med Inform Decis Mak ; 22(1): 40, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-35168629

RESUMO

INTRODUCTION: Syphilis is a sexually transmitted disease (STD) caused by Treponema pallidum subspecies pallidum. In 2016, it was declared an epidemic in Brazil due to its high morbidity and mortality rates, mainly in cases of maternal syphilis (MS) and congenital syphilis (CS) with unfavorable outcomes. This paper aimed to mathematically describe the relationship between MS and CS cases reported in Brazil over the interval from 2010 to 2020, considering the likelihood of diagnosis and effective and timely maternal treatment during prenatal care, thus supporting the decision-making and coordination of syphilis response efforts. METHODS: The model used in this paper was based on stochastic Petri net (SPN) theory. Three different regressions, including linear, polynomial, and logistic regression, were used to obtain the weights of an SPN model. To validate the model, we ran 100 independent simulations for each probability of an untreated MS case leading to CS case (PUMLC) and performed a statistical t-test to reinforce the results reported herein. RESULTS: According to our analysis, the model for predicting congenital syphilis cases consistently achieved an average accuracy of 93% or more for all tested probabilities of an untreated MS case leading to CS case. CONCLUSIONS: The SPN approach proved to be suitable for explaining the Notifiable Diseases Information System (SINAN) dataset using the range of 75-95% for the probability of an untreated MS case leading to a CS case (PUMLC). In addition, the model's predictive power can help plan actions to fight against the disease.


Assuntos
Sífilis Congênita , Sífilis , Brasil/epidemiologia , Feminino , Humanos , Sistemas de Informação , Gravidez , Cuidado Pré-Natal , Sífilis/diagnóstico , Sífilis/epidemiologia , Sífilis Congênita/diagnóstico , Sífilis Congênita/epidemiologia
16.
An Acad Bras Cienc ; 94(suppl 4): e20211024, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36515326

RESUMO

Large-scale fluid flow in porous media demands intense computations and occurs in the most diverse applications, including groundwater flow and oil recovery. This article presents novel computational strategies applied to reservoir geomechanics. Advances are proposed for the efficient assembly of finite element matrices and the solution of linear systems using highly vectorized code in MATLAB. In the CPU version, element matrix assembly is performed using conventional vectorization procedures, based on two strategies: the explicit matrices, and the multidimensional products. Further assembly of the global sparse matrix is achieved using the native sparse function. For the GPU version, computation of the complete set of element matrices is performed with the same strategies as the CPU approach, using gpuArray structures and the native CUDA support provided by MATLAB Parallel Computing Toolbox. Solution of the resulting linear system in CPU and GPU versions is obtained with two strategies using a one-way approach: the native conjugate gradient solver (pcg), and the one provided by the Eigen library. A broad discussion is presented in a dedicated benchmark, where the different strategies using CPU and GPU are compared in processing time and memory requirements. These analyses present significant speedups over serial codes.


Assuntos
Aceleração , Algoritmos
17.
Molecules ; 27(15)2022 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-35956954

RESUMO

The explanation of the anomeric effect in terms of underlying quantum properties is still controversial almost 70 years after its introduction. Here, we use a method called Relative Energy Gradient (REG), which is able to compute chemical insight with a view to explaining the anomeric effect. REG operates on atomic energy contributions generated by the quantum topological energy decomposition Interacting Quantum Atoms (IQA). Based on the case studies of dimethoxymethane and 2-fluorotetrahydropyran, we show that the anomeric effect is electrostatic in nature rather than governed by hyperconjugation.

18.
Int J Hosp Manag ; 103: 103201, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35261426

RESUMO

The sudden irruption of COVID-19 has paralysed, even devastated, numerous industries. Academic and industry publications also convey the destructive impacts of this phenomenon on hospitality and tourism businesses. While business owners and managers are still constrained by unpredictability, restrictions, and ongoing uncertainty, those vying to continue will need to build their adaptive skill repertoire to cope with the crisis-related regime. This study is primarily concerned with businesses' adaptation phase from owners/managers' viewpoints, including how they manage and envision a future coexistence with COVID-19 threats. Drawing on an international sample of owners/managers of hospitality and tourism businesses, and considering the foundations of the dynamic capabilities framework, eight dimensions emerged from the findings. Five of these, persevering, dynamic, austere restrictions, business environment, and stakeholder, strongly suggest the relevance of reconfiguring, a cluster of dynamic capabilities. Together, the dimensions demonstrate participants' strong commitment to navigate through the threat while pursuing socioeconomic sustainability.

19.
Emerg Infect Dis ; 27(1): 47-56, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33350931

RESUMO

A major outbreak of yellow fever (YF) occurred in Brazil during 2016-2018. Epizootics in New World nonhuman primates are sentinel events for YF virus circulation. However, genus-specific susceptibilities and suitability for YF surveillance remain poorly understood. We obtained and compared epidemiologic, histopathologic, immunohistochemical, and molecular results from 93 human and 1,752 primate cases submitted during the recent YF outbreak in Brazil (2017), with the support of the Brazilian National YF Surveillance Program. We detected heterogeneous YF-associated profiles among the various genera of primates we analyzed. Alouatta primates were the most reliable sentinel; Sapajus and Callicebus primates had higher viral loads but lower proportional mortality rates. Callithrix primates were the least sensitive, showing lower viral loads, lower proportional mortality rates, and no demonstrable YF virus antigen or extensive lesions in liver, despite detectable viral RNA. These differences in susceptibility, viral load, and mortality rates should be considered in strategic surveillance of epizootics and control measures for YF.


Assuntos
Alouatta , Febre Amarela , Animais , Brasil/epidemiologia , Humanos , Primatas , Febre Amarela/epidemiologia , Febre Amarela/veterinária , Vírus da Febre Amarela/genética
20.
Am J Kidney Dis ; 78(1): 48-56, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33333147

RESUMO

RATIONALE AND OBJECTIVE: Although low estimated glomerular filtration rate (eGFR) is associated with cardiovascular disease (CVD) events and mortality, the clinical significance of variability in eGFR over time is uncertain. This study aimed to evaluate the associations between variability in eGFR and the risk of CVD events and all-cause mortality. STUDY DESIGN: Longitudinal analysis of clinical trial participants. SETTINGS AND PARTICIPANTS: 7,520 Systolic Blood Pressure Intervention Trial (SPRINT) participants ≥50 year of age with 1 or more CVD risk factors. PREDICTORS: eGFR variability, estimated by the coefficient of variation of eGFR assessments at the 6th, 12th, and 18-month study visits. OUTCOMES: The SPRINT primary CVD composite outcome (myocardial infarction, acute coronary syndrome, stroke, heart failure, or CVD death) and all-cause mortality from month 18 to the end of follow-up. ANALYTICAL APPROACH: Cox models were used to evaluate associations between eGFR variability and CVD outcomes and all-cause mortality. Models were adjusted for demographics, randomization arm, CVD risk factors, albuminuria, and eGFR at month 18. RESULTS: Mean age was 68 ± 9 years; 65% were men; and 58% were White. The mean eGFR was 73 ± 21 (SD) mL/min/1.73 m2 at 6 months. There were 370 CVD events and 154 deaths during a median follow-up of 2.4 years. Greater eGFR variability was associated with higher risk for all-cause mortality (hazard ratio [HR] per 1 SD greater variability, 1.29; 95% CI, 1.14-1.45) but not CVD events (HR, 1.05; 95% CI, 0.95-1.16) after adjusting for albuminuria, eGFR, and other CVD risk factors. Associations were similar when stratified by treatment arm and by baseline CKD status, when accounting for concurrent systolic blood pressure changes, use of angiotensin-converting enzyme inhibitors or angiotensin receptor blockers, and diuretic medications during follow up. LIMITATIONS: Persons with diabetes and proteinuria > 1 g/d were excluded. CONCLUSIONS: In trial participants at high risk for CVD, greater eGFR variability was independently associated with all-cause mortality but not CVD events.


Assuntos
Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/fisiopatologia , Taxa de Filtração Glomerular , Idoso , Pressão Sanguínea , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Medição de Risco
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