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1.
Nutr Rev ; 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38684926

RESUMO

CONTEXT: Premenstrual syndrome (PMS) affects approximately 48% of women of reproductive age worldwide. It can lead to functional impairment, lower quality of life, and decreased work productivity. Despite the availability of medical treatment options, women are seeking alternative interventions because of concerns of harmful side effects and limited evidence of efficacy associated with pharmacological treatments. To date, high-quality research investigating the effects of dietary and nutrient intervention on PMS is limited. OBJECTIVE: This systematic review investigated the effect of nutritional interventions on the psychological symptoms of PMS. DATA SOURCES: Five electronic databases were searched for randomized controlled trials (RCTs) published in English from inception to October 2022. Trials eligible for inclusion were nutritional intervention studies involving women of reproductive age that measured PMS-associated psychological outcomes. DATA EXTRACTION: Articles were selected using prespecified inclusion criteria. Data screening and extraction and risk-of-bias assessments were conducted by 3 independent reviewers using article screening software and the Cochrane Risk of Bias 2 tool. DATA ANALYSIS: Thirty-two articles reporting on 31 RCTs involving 3254 participants, ranging in age from 15 to 50 years were included and narratively reviewed. Only 1 of the included studies had a low risk of bias. Treatment with vitamin B6, calcium, and zinc consistently had significant positive effects on the psychological symptoms of PMS. There was insufficient evidence to support the effects of vitamin B1, vitamin D, whole-grain carbohydrates, soy isoflavones, dietary fatty acids, magnesium, multivitamin supplementation, or PMS-specific diets. CONCLUSIONS: There is some evidence to support the use of nutritional interventions for improving psychological symptoms of PMS. However, more research using consistent protocols, procedures to minimize risk of bias, intention-to-treat analysis, and clearer reporting is required to provide conclusive nutritional recommendations for improving PMS-related psychological outcomes. PROSPERO REGISTRATION NO: CRD42022369999.

2.
Front Vet Sci ; 10: 1248024, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37781293

RESUMO

Introduction: Dogs presenting as paraplegic without nociception due to a thoracolumbar intervertebral disc extrusion provide a difficult decision to both the clinician and the owner. The prognosis when performing surgical decompression remains guarded. Aside from significant extradural compression, these dogs often have a significant secondary spinal cord injury, which has shown to be an important factor in determining both the likelihood of developing progressive myelomalacia and the return to ambulation. Materials and methods: This is a retrospective, observational, single centre study including 82 dogs presenting as paraplegic with absent nociception diagnosed with an intervertebral disc extrusion. Patients underwent MRI of the thoracolumbar spine, including a gradient echo sequence which was evaluated for the presence of intramedullary signal void artefacts. Decompressive surgery was performed, and patients were evaluated for the presence of nociception at short term follow up (at least four weeks post-surgery). Results: Overall, 59.8% of patients regained nociception within the study period. This number was significantly reduced to 33.3% when multiple gradient echo signal voids were present (compared to 67.3% of dogs without signal voids). There was no significant difference in the rate of developing progressive myelomalacia between groups. Conclusions: This paper adds to the existing literature and suggests that the gradient echo sequence may be of use when assessing acute spinal cord injury in the context of intervertebral disc extrusion and how it relates to prognosis.

3.
J Am Anim Hosp Assoc ; 59(5): 234-240, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37708478

RESUMO

A 4 yr old female neutered Labrador retriever was referred with a history of left hind-limb lameness and an acute, nonpainful, subcutaneous mass on the medial aspect of the left stifle. Stifle radiographs and fine needle aspirates of the soft tissue mass performed by the referring veterinarian confirmed the presence of predominantly highly granulated mast cells, consistent with a mast cell tumor. Computed tomography demonstrated a soft tissue mass centered on the left medial stifle, with associated joint effusion and polyostotic lytic lesions on the tibial plateau and distal patella. Ultrasound-guided aspirates of the liver, spleen, and popliteal lymph nodes were obtained to rule out further metastatic spread. Cytology of the joint fluid demonstrated a low number of well-differentiated mast cells. Surgical and oncological interventions were discussed, and full hind-limb amputation was elected. Histopathological analysis of the submitted tissues after amputation diagnosed a subcutaneous mast cell tumor with neoplastic cell infiltrate extending into sections of joint capsule and synovial membrane. Infiltration to the tibia and distal patella were suspected following the presence of mast cell clusters in both osteolytic lesions. No evidence of metastasis was identified in the popliteal lymph node. Postoperative monitoring of iliac lymph node size using ultrasound did not identify evidence of metastasis 12 mo postoperatively.


Assuntos
Doenças do Cão , Neoplasias , Feminino , Animais , Cães , Joelho de Quadrúpedes/cirurgia , Tíbia , Mastócitos , Patela , Neoplasias/veterinária , Doenças do Cão/cirurgia
4.
Vet Rec ; 190(2): e780, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34352128

RESUMO

BACKGROUND: Computed tomography (CT) and ultrasonography (US) may be used to assist staging in dogs with lymphoma. The imaging features of splenic and hepatic infiltration have never been directly compared in the same population of dogs. METHODS: The aim of this retrospective study was to describe and compare the CT and US findings of the liver and spleen in dogs with confirmed hepatic and/or splenic lymphoma and compare imaging and cytological diagnoses. RESULTS: CT and US studies of 18 dogs with multicentric lymphoma involving the liver and/or the spleen were retrospectively evaluated. US detected abnormalities more frequently than CT in the spleen with lymphoma, whereas CT detected abnormalities more frequently in the liver with lymphoma. The two diagnostic imaging modalities often disagreed in the findings, including the imaging classification of the organ as normal or abnormal. CONCLUSION: US and CT often disagree in the imaging findings present in hepatic and splenic lymphoma. The results of this study suggest that cytologic evaluation of both the liver and spleen is advisable regardless of their US or CT appearance for detection of lymphoma.


Assuntos
Doenças do Cão , Linfoma , Neoplasias Esplênicas , Animais , Doenças do Cão/diagnóstico por imagem , Cães , Fígado/diagnóstico por imagem , Linfoma/diagnóstico por imagem , Linfoma/veterinária , Estudos Retrospectivos , Baço/diagnóstico por imagem , Neoplasias Esplênicas/diagnóstico por imagem , Neoplasias Esplênicas/veterinária , Tomografia Computadorizada por Raios X/veterinária , Ultrassonografia/veterinária
5.
Vet Rec ; 186(16): 533, 2020 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-31748423

RESUMO

OBJECTIVES: The medullary rim sign (MRS) is an ultrasonographic (US) feature identified in normal and diseased feline kidneys. The prevalence and potential clinical significance of the MRS in a referral hospital cat population was investigated. METHODS: Retrospective case-control study. US images from 661 cats were reviewed. Cats with an MRS were identified and compared with equal number of time-matched control cats. Medical data and MRS features, including thickness, intensity and symmetry, were collected. Associations between independent variables and the MRS were examined with conditional and unconditional logistic regression, with initial univariable, and subsequent multivariable analysis. RESULTS: Of the 661 reviewed cats, 243 (36.8 per cent) showed a variation of the MRS. A thin MRS (133 cats) was not associated with azotaemic renal disease (P=0.87). A thick MRS (110 cats) was associated with azotaemic renal disease (P=0.001). There was an association between the presence of MRS and a final diagnosis of feline infectious peritonitis (FIP) (P=0.028). CONCLUSIONS: The MRS is a common finding in cats. In this cat population, a thick MRS was associated with azotaemic renal disease, while a thin MRS was not. In cases with a clinical suspicion of FIP, the MRS may be related to the underlying disease process and not be an incidental finding.


Assuntos
Doenças do Gato/diagnóstico por imagem , Nefropatias/veterinária , Medula Renal/diagnóstico por imagem , Animais , Estudos de Casos e Controles , Doenças do Gato/epidemiologia , Gatos , Peritonite Infecciosa Felina/diagnóstico , Feminino , Nefropatias/diagnóstico por imagem , Nefropatias/epidemiologia , Masculino , Prevalência , Estudos Retrospectivos , Ultrassonografia/veterinária
6.
Am J Vet Res ; 80(1): 69-73, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30605037

RESUMO

OBJECTIVE To determine the mean diameter of the main portal vein (PV) in healthy dogs by use of CT angiography, identify any associations between PV diameter and certain dog characteristics, and validate a clinically valuable ratio for quantifying the size of the PV. ANIMALS 100 dogs with no hepatic, cardiac, or vascular anomalies that underwent abdominal CT angiography. PROCEDURES Diameters of the main PV, abdominal aorta (Ao), and caudal vena cava (CVC) were measured by 2 observers at a defined location on postcontrast CT angiographic images in axial, sagittal, and transverse planes. Dog characteristics were evaluated for associations with PV diameter, and a PV:Ao diameter ratio was calculated. Intraclass correlations were calculated to assess intra- and interobserver agreement in vessel diameter measurements. RESULTS Mean diameter values were 7.9 mm (range, 4.1 to 14.8 mm) for the PV, 8.9 mm (range, 3.7 to 13.7 mm) for the Ao, and 11.4 mm (range, 4.4 to 22.5 mm) for the CVC. The PV:Ao diameter ratio was 0.91 mm. The PV diameter was significantly associated with dog body weight but not with dog age, sex, or neuter status. Intra- and interobserver reliabilities for measurements of all 3 vessels were considered excellent (intraclass correlation coefficients > 0.85). CONCLUSIONS AND CLINICAL RELEVANCE Findings indicated that the PV:Ao diameter ratio was a repeatable measurement that may be useful for evaluating the size of the portal vasculature in dogs and possibly for distinguishing healthy PVs from abnormal PVs in dogs with hepatic vascular anomalies.


Assuntos
Angiografia por Tomografia Computadorizada/veterinária , Cães/anatomia & histologia , Veia Porta/anatomia & histologia , Animais , Pesos e Medidas Corporais/veterinária , Feminino , Masculino , Veia Porta/diagnóstico por imagem , Valores de Referência
7.
J Phys Chem B ; 120(26): 6215-24, 2016 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-27079171

RESUMO

Poly(fluorene-alt-thiophene) (PFT) is a conjugated polyelectrolyte that self-assembles into rod-like micelles in water, with the conjugated polymer backbone running along the length of the micelle. At modest concentrations (∼10 mg/mL in aqueous solutions), PFT forms hydrogels, and this work focuses on understanding the structure and intermolecular interactions in those gel networks. The network structure can be directly visualized using cryo electron microscopy. Oscillatory rheology studies further tell us about connectivity within the gel network, and the data are consistent with a picture where polymer chains bridge between micelles to hold the network together. Addition of tetrahydrofuran (THF) to the gels breaks those connections, but once the THF is removed, the gel becomes stronger than it was before, presumably due to the creation of a more interconnected nanoscale architecture. Small polymer oligomers can also passivate the bridging polymer chains, breaking connections between micelles and dramatically weakening the hydrogel network. Fits to solution-phase small-angle X-ray scattering data using a Dammin bead model support the hypothesis of a bridging connection between PFT micelles, even in dilute aqueous solutions. Finally, time-resolved microwave conductivity measurements on dried samples show an increase in carrier mobility after THF annealing of the PFT gel, likely due to increased connectivity within the polymer network.


Assuntos
Hidrogéis/química , Polieletrólitos/química , Microscopia Crioeletrônica , Eletricidade , Furanos/química , Cinética , Micelas , Micro-Ondas , Modelos Químicos , Reologia , Espalhamento a Baixo Ângulo , Soluções/química , Substâncias Viscoelásticas/química , Água/química , Difração de Raios X
8.
Adv Mater ; 27(31): 4578-84, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26134594

RESUMO

By controlling the polymer/polymer blend self-organization rate, all-polymer solar cells composed of a high-mobility, crystalline, naphthalene diimide-selenophene copolymer acceptor and a benzodithiophene-thieno[3,4-b]thiophene copolymer donor are achieved with a record 7.7% power conversion efficiency and a record short-circuit current density (18.8 mA cm(-2)).

9.
Science ; 348(6241): 1340-3, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-26089510

RESUMO

The efficiency of biological photosynthesis results from the exquisite organization of photoactive elements that promote rapid movement of charge carriers out of a critical recombination range. If synthetic organic photovoltaic materials could mimic this assembly, charge separation and collection could be markedly enhanced. We show that micelle-forming cationic semiconducting polymers can coassemble in water with cationic fullerene derivatives to create photoinduced electron-transfer cascades that lead to exceptionally long-lived polarons. The stability of the polarons depends on the organization of the polymer-fullerene assembly. Properly designed assemblies can produce separated polaronic charges that are stable for days or weeks in aqueous solution.


Assuntos
Fulerenos/química , Fotossíntese , Polímeros/química , Transporte de Elétrons , Semicondutores
10.
J Phys Chem B ; 115(30): 9473-90, 2011 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-21682315

RESUMO

Electrostatic properties of proteins are crucial for their functionality. Carboxyamides are small polar groups that, as peptide bonds, are principal structural components of proteins that govern their electrostatic properties. We investigated the medium dependence of the molar polarization and of the permanent dipole moments of amides with different state of alkylation. The experimentally measured and theoretically calculated dipole moments manifested a solvent dependence that increased with the increase in the media polarity. We ascribed the observed enhancement of the amide polarization to the reaction fields in the solvated cavities. Chloroform, for example, caused about a 25% increase in the amide dipole moments determined for vacuum, as the experimental and theoretical results demonstrated. Another chlorinated solvent, 1,1,2,2-tetrachloroethane, however, caused an "abnormal" increase in the experimentally measured amide dipoles, which the theoretical approaches we used could not readily quantify. We showed and discussed alternatives for addressing such discrepancies between theory and experiment.


Assuntos
Amidas/química , Modelos Teóricos , Proteínas/química , Etano/análogos & derivados , Etano/química , Hidrocarbonetos Clorados/química , Eletricidade Estática
11.
J Phys Chem A ; 113(13): 3096-107, 2009 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-19267468

RESUMO

Photoinduced processes, leading to charge-transfer states with extended lifetimes, are of key importance for solar-energy-conversion applications. Utilizing external heavy-atom effect allowed us to photogenerate long-lived transients of electron donor-acceptor dyads. For an electron acceptor and a principal chromophore of the dyads, we selected N-methylacridinium, and for electron donors thiophene, bithiophene, and terthiophene were selected. While the photoinduced charge transfer, mediated by the investigated dyads, occurred in the picosecond time domain, the lifetime of the transients extended to the microsecond time domain. We ascribed the relatively long lifetimes to the triplet character of the observed transients. An increase in the size of the donor lowered the energy of the charge-transfer states of the dyads. When the energy level of the acridinium triplet lies below the energy level of the charge-transfer state, the locally excited triplet accounted for the long-lived transient. For the conjugates with charge-transfer states lying below all other excited states, the long-lived transients were, indeed, the charge-transfer species.


Assuntos
Acridinas/química , Processos Fotoquímicos , Tiofenos/química , Adsorção , Estrutura Molecular , Espectrofotometria
12.
J Phys Chem A ; 113(7): 1259-67, 2009 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-19199684

RESUMO

The estimation of the driving force for photoinduced charge-transfer processes, using the Rehm-Weller equation, requires the employment of redox and spectroscopic quantities describing the participating electron donor and acceptor. Although the spectroscopic data are usually obtained from diluted solutions, the redox potentials are most frequently obtained from electrochemical measurements conducted in concentrated electrolyte solutions. To correct for the differences in the media, in which the various types of measurements are conducted, a term, based on the Born equation for solvation energy of ions, is introduced in the Rehm-Weller equation. The Born correction term, however, requires a prior knowledge of the dielectric constants of the electrolyte solutions used for the redox measurements. Because of limited information for such dielectrics, the values for the dielectric constants of electrolyte solutions are approximated to the values of the dielectric constants of the corresponding neat solvents. We examined the validity of this approximation. Using cyclic voltammetry, we recorded the first one-electron oxidation potential of ferrocene for three different solvents in the presence of 1-500 mM supporting electrolyte. The dielectric constants for some of the electrolyte solutions were extracted from fluorescence measurements of a dimethylaminonaphthalimide chromophore that exhibits pronounced solvatochromism. The dielectric constants of the concentrated electrolyte solutions correlated well with the corresponding oxidation potentials. The dependence of the oxidation potential of ferrocene on the electrolyte concentration for different solvents revealed that the abovementioned approximation in the Born correction term indeed introduces a significant error in the estimation of the charge-transfer driving force from redox data collected using relatively nonpolar solvents.


Assuntos
Eletrólitos/química , Compostos Ferrosos/química , Impedância Elétrica , Eletroquímica , Metalocenos , Cloreto de Metileno/química , Naftalimidas/química , Oxirredução , Solventes/química
13.
Langmuir ; 24(22): 13218-24, 2008 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-18950212

RESUMO

Treatment with oxygen-containing plasma is an essential step for the fabrication of devices containing components of polydimethylsiloxane (PDMS). Such oxidative treatment chemically modifies the surface of PDMS allowing it to permanently adhere to glass, quartz, PDMS and other silica-based substrates. Overexposure of PDMS to oxidative gas plasma, however, compromises its adhesiveness. Therefore, regulation of the duration and the conditions of the plasma treatment is crucial for achieving sufficient surface activation without overoxidation. Using a semiquantitative ternary approach, we evaluated the quality of adhesion ( QA) between flat PDMS and glass substrates pretreated with oxygen plasma under a range of different conditions. The quality of adhesion manifested good correlation trends with the surface properties of the pretreated PDMS. Examination of the QA dependence on the treatment duration and on the pressure and the RF power of the plasma revealed a range of oxidative conditions that allowed for permanent adhesion with quantitative yields.


Assuntos
Dimetilpolisiloxanos/química , Oxigênio/química , Adesividade , Vidro , Microscopia de Força Atômica , Polímeros , Pressão , Dióxido de Silício/química , Solventes , Propriedades de Superfície , Resistência à Tração , Fatores de Tempo
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