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1.
Echocardiography ; 41(10): e15941, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39367773

RESUMO

BACKGROUND: Patients with chronic kidney disease (CKD) possess a pronounced risk for cardiovascular events. A noninvasive left ventricular pressure-strain loop (LV-PSL) has recently been introduced to detect subtler changes in cardiac function. This study aims to investigate the value of LV-PSL for quantitative assessment of myocardial work (MW) in patients with CKD. METHODS: Seventy-five patients with CKD were enrolled retrospectively (37 patients with CKD Stages 2-3, and 38 patients with CKD Stages 4-5), and 35 healthy volunteers were included as controls. All subjects underwent transthoracic echocardiography. LV-PSL analysis was performed to estimate LV MW and efficiency. Global work index (GWI), global constructive work (GCW), global wasted work (GWW), and global work efficiency (GWE) were obtained by echocardiography, and the differences among the groups were compared. RESULTS: There was a significant increase in GWW and reduction in GWE in patients with CKD compared to normal controls (p < 0.05). No significant difference in GWI and GCW was observed among the three groups. Multiple linear regression revealed that increased GWW was significantly associated with age, serum creatinine, and systolic pressure, and decreased GWE was associated with age, serum creatinine, and GLS. CONCLUSION: LV-PSL can be used for noninvasive quantitative assessment of MW in patients with CKD, providing a new sensitive approach for the clinical assessment of myocardial function.


Assuntos
Ecocardiografia , Insuficiência Renal Crônica , Disfunção Ventricular Esquerda , Humanos , Masculino , Feminino , Insuficiência Renal Crônica/fisiopatologia , Insuficiência Renal Crônica/complicações , Disfunção Ventricular Esquerda/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/etiologia , Disfunção Ventricular Esquerda/complicações , Pessoa de Meia-Idade , Ecocardiografia/métodos , Estudos Retrospectivos , Reprodutibilidade dos Testes , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/fisiopatologia , Pressão Ventricular/fisiologia , Adulto
2.
J Int Med Res ; 48(10): 300060520966884, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33135534

RESUMO

OBJECTIVE: To assess the biomechanical properties that influence wrist fracture, so as to provide the theoretical basis for simulation experiments to aid the optimal design of wrist protectors. METHODS: Six cadaveric wrists were included as experimental specimens. Wrist specimens wearing wrist protectors formed the experimental group and unprotected wrist specimens formed the control group. The wrist specimens were axially loaded under physiological loads and the stress magnitude and distribution of the experimental and control groups were obtained. A three-dimensional wrist finite element model of a healthy volunteer was developed to verify the rationality and effectiveness of the cadaveric wrist models. RESULTS: Under normal physiological loads, the stress on the radioulnar palmar unit was high and manifested in the form of pressure, while the stress on the radioulnar dorsal unit was lower and manifested in the form of tension. The stresses on the radial distal palmar, ulnar distal palmar, radial distal dorsal, ulnar distal dorsal, radial proximal palmar and ulnar proximal palmar units in the experimental group were less than those in the control group. CONCLUSION: Under physiological loads, wearing a wrist protector can reduce the stress on the radioulnar distal palmar, radioulnar proximal palmar and radioulnar distal dorsal units, while having no obvious effect on the radioulnar proximal dorsal units.


Assuntos
Fraturas do Rádio , Punho , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Articulação do Punho
3.
Pest Manag Sci ; 2018 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-29528561

RESUMO

BACKGROUND: The autoparasitoid Encarsia sophia and the primary parasitoid Eretmocerus hayati are two important parasitoids used against the whitefly Bemisia tabaci, with different reproductive strategies. To incorporate these two parasitoids into a sustainable whitefly control program, it is necessary to evaluate and compare their fitness and biocontrol effectiveness under identical experimental conditions. The demographic characteristics, parasitism rate and host-feeding rate of En. sophia and Er. hayati were analyzed using an age-stage, two-sex life table and the CONSUME-MSChart computer program. RESULTS: The mean fecundity of Er. hayati (211.4 offspring per female) was significantly higher than that of En. sophia (101.6 offspring per female), although the oviposition days of En. sophia was longer than that of Er. hayati. No significant difference was found in the intrinsic rate of increase (r), finite rate of increase (λ) or net reproduction rate (R0 ) between the two parasitoid species, but the mean generation time (T) of En. sophia (18.8 days) was significantly shorter than that of Er. hayati (20.5 days). The net host feeding rate (C0 ) of En. sophia was 84.1 whiteflies per individual, significantly higher than the 17.6 whiteflies per individual consumed by Er. hayati. The finite killing rate (ν) of En. sophia (0.6713) for whitefly was significantly greater than that produced by Er. hayati (0.3652). CONCLUSION: The En. sophia population can increase faster and have a higher killing potential than the Er. hayati population. Taking both the demographic fitness and killing potential of the two parasitoids into consideration, En. sophia would be the preferred choice to release in a biological control program. © 2018 Society of Chemical Industry.

4.
Neurosci Lett ; 614: 89-94, 2016 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-26779676

RESUMO

Clinical studies have demonstrated that a single dose of ketamine produces complete remission within 24h in some depression patients. The ability of ketamine to produce fast-acting antidepressant-like effects in animal models depends on rapid synthesis of brain-derived neurotrophic factor (BDNF). Here we examined effects of a single dose dizocilpine, a non-competitive NMDA receptor antagonist, on the behavioral and neurobiological changes in rats treated with a single high dose reserpine, which is a monoamine re-uptake blocker and depletes monoamines in the brain with the outcome of depression-like symptoms in animals. A single high dose reserpine (4.0mg/kg) was given to rats intraperitoneally. Forty-eight hours later, the rats showed depressive symptoms as evidenced by decreased locomotor activity in the open field and increased immobility time in the forced swim test. Meanwhile, the treatment decreased BDNF levels and neurogenesis in the hippocampus. Pretreatment of a single dose dizocilpine (0.30mg/kg), however, prevented all the reserpine-induced changes, except for GluN1 subunit. These results are suggestive of the involvement of neurogenesis and BDNF in the rapid-acting antidepressant-like behavioral effects of the NMDA receptor antagonists in the reserpinized rats.


Assuntos
Antidepressivos/farmacologia , Depressão/tratamento farmacológico , Maleato de Dizocilpina/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Reserpina , Animais , Antidepressivos/uso terapêutico , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Giro Denteado/efeitos dos fármacos , Giro Denteado/metabolismo , Giro Denteado/patologia , Depressão/induzido quimicamente , Depressão/psicologia , Maleato de Dizocilpina/uso terapêutico , Injeções Intraperitoneais , Masculino , Atividade Motora/efeitos dos fármacos , Neurogênese , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/metabolismo
5.
Insect Sci ; 23(1): 134-44, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25393924

RESUMO

The functional responses of two parasitoids, Eretmocerus hayati Zolnerowich & Rose and Encarsia sophia Girault & Dodd, of whitefly Bemisia tabaci Gennadius Middle East-Asia Minor 1 were studied under laboratory conditions. In addition, the influence of host density and host stage on the competitive interactions between the two parasitoids, and biological control effect on whitefly were evaluated. In the functional response study, adult parasitoids were tested individually, with a conspecific or heterospecific competitor. Both Er. hayati and En. sophia exhibited a type II response to increasing host density, whether a conspecific or heterospecific competitor was present or not. Difference of searching rates and handling times between treatments suggested interference interactions existed between two parasitoid species. In the host stage preference study, two parasitoid species were jointly tested. Er. hayati had a competitive advantage over En. sophia when provided young host instars (first and second instar), whereas no advantage was found on old host instars (third and fourth instar). The biological control effect of Er. hayati and En. sophia in different introductions varied with host density. However, the effect of host instar on host mortality was not significant. These findings provide information for the practice of biological control and give better insight into how parasitoid species may coexist in diverse environments.


Assuntos
Hemípteros/parasitologia , Interações Hospedeiro-Parasita , Himenópteros/fisiologia , Controle Biológico de Vetores , Animais , Feminino , Gossypium , Hemípteros/crescimento & desenvolvimento , Hemípteros/fisiologia , Ninfa/parasitologia
6.
PLoS One ; 8(11): e82003, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24312394

RESUMO

Understanding the dynamics of potential inter- and intraspecific competition in parasitoid communities is crucial in the screening of efficient parasitoid species and for utilization of the best parasitoid species combinations. In this respect, the host-parasitoid systems, Bemisia tabaci and two parasitoids, Eretmocerus hayati (exotic) and Encarsia sophia (existing) were studied under laboratory conditions to investigate whether interference competition between the exotic and existing species occurs as well as the influence of potential interference competition on the suppression of the host B. tabaci. Studies on interspecific-, intraspecific- and self-interference competition in two parasitoid species were conducted under both rich and limited host resource conditions. Results showed that (1) both parasitoid species negatively affect the progeny production of the other under both rich and limited host resource conditions; (2) both parasitoid species interfered intraspecifically on conspecific parasitized hosts when the available hosts are scarce and; 3) the mortality of B. tabaci induced by parasitoids via parasitism, host-feeding or both parasitism and host-feeding together varied among treatments under different host resource conditions, but showed promise for optimizing control strategies. As a result of our current findings, we suggest a need to investigate the interactions between the two parasitoids on continuous generations.


Assuntos
Comportamento Animal , Vespas/fisiologia , Animais , Especificidade da Espécie
7.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 4): o1131, 2012 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-22589986

RESUMO

In the title compound, C(13)H(12)O(2), the dihedral angle between the pyran-one and phenyl rings is 57.55 (9)°. In the crystal, the mol-ecules are linked by π-π stacking inter-actions between the parallel pyran-one rings of neighboring mol-ecules with distances of 3.5778 (11) Šand 3.3871 (11) Šbetween the planes. C-H⋯O interactions also occur.

8.
World J Gastroenterol ; 16(29): 3674-9, 2010 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-20677339

RESUMO

AIM: To evaluate tracking of magnetically labeled mesenchymal stem cells (MSCs) after intraportal transplantation. METHODS: Mononuclear cells were isolated from bone marrow aspirates of pigs by density gradient centrifugation, cultured and expanded, after which, they were incubated with super paramagnetic iron oxide (SPIO). Prussian blue staining was performed to highlight intracellular iron. To establish swine models of acute liver injury, 0.5 g/kg D-galactosamine was administrated to 10 pigs, six of which were injected via their portal veins with SPIO-labeled MSCs, while the remaining four were injected with unlabeled cells. Magnetic resonance imaging (MRI) was performed with a clinical 1.5T MR scanner immediately before transplantation and 6 h, 3 d, 7 d and 14 d after transplantation. Prussian blue staining was again performed with the tissue slices at the endpoint. RESULTS: Prussian blue staining of SPIO-labeled MSCs had a labeling efficiency of almost 100%. Signal intensity loss in the liver by SPIO labeling on the FFE (T2*WI) sequence persisted until 14 d after transplantation. Histological analysis by Prussian blue staining confirmed homing of labeled MSCs in the liver after 14 d; primarily distributed in hepatic sinusoids and liver parenchyma. CONCLUSION: MSCs were successfully labeled with SPIO in vitro. MRI can monitor magnetically labeled MSCs transplanted into the liver.


Assuntos
Fígado/lesões , Fígado/cirurgia , Magnetismo , Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/fisiologia , Transplante Autólogo , Animais , Células Cultivadas , Compostos Férricos/química , Compostos Férricos/metabolismo , Fígado/citologia , Células-Tronco Mesenquimais/citologia , Nanopartículas Metálicas/química , Distribuição Aleatória , Suínos
9.
Biomaterials ; 30(27): 4533-8, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19500837

RESUMO

Clinical use of bioartificial livers (BAL) strongly relies on the development of bioreactors. In this study, we developed a multi-layer radial-flow bioreactor based on galactosylated chitosan nanofiber scaffolds and evaluated its efficacy in vitro. The bioreactor contains 65 layers of stacked flat plates, on which the nanofiber scaffolds were electrospinned for hepatocyte immobilization and aggregation. Culture medium containing pig red blood cells (RBCs) was perfused from the center to periphery, so that exchange materials are sufficient to afford enough oxygen. We determined the parameters for hepatocyte-specific function and general metabolism and also measured the oxygen consumption rate (OCR). Microscope and scanned electron microscopy observation showed a tight adhesion between cells and scaffolds. Compared with the control (bioreactors without nanofiber scaffolds), the number of adhered cells in our bioreactor was 1.59-fold; the protein-synthesis capacity of hepatocytes was 1.73-fold and urea was 2.86-fold. Moreover, the OCR of bioreactors with RBCs was about 1.91-fold that of bioreactors without RBCs. The galactosylated chitosan nanofiber scaffolds introduced into our new bioreactor greatly enhanced cell adhesion and function, and the RBCs added into the culture medium were able to afford enough oxygen for hepatocytes. Importantly, our new bioreactor showed an exciting efficiency, and it may afford the short-term support of patients with hepatic failure.


Assuntos
Reatores Biológicos , Quitosana/metabolismo , Galactose/metabolismo , Nanoestruturas/química , Alicerces Teciduais/química , Animais , Contagem de Células , Sobrevivência Celular , Glicosilação , Hepatócitos/metabolismo , Hepatócitos/patologia , Hepatócitos/ultraestrutura , Especificidade de Órgãos , Oxigênio , Consumo de Oxigênio , Reologia , Sus scrofa
10.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 2): m413, 2008 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-21201359

RESUMO

In the crystal structure of the title compound, {[Fe(2)(C(7)H(3)NO(4))(2)(H(2)O)(6)]·4H(2)O}(n), there are two types of coordination for the Fe(II) atoms. One Fe(II) atom is in a distorted octa-hedral N(2)O(4) environment, with two chelating rings from the pyridine-dicarboxyl-ate ligands and two O atoms from the water mol-ecules, while the other is in a distorted octa-hedral O(6) environment with two O atoms from the pyridine-dicarboxyl-ate ligands and four O atoms from the water mol-ecules. Both Fe(II) atoms lie on crystallographic centers of symmetry. The complex possesses an infinite chain structure running along the [101] direction. These chains are inter-connected by the uncoordinated water mol-ecules through O-H⋯O hydrogen bonds.

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