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1.
J Clin Psychol ; 80(2): 391-405, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37866970

RESUMO

OBJECTIVES: Few studies have investigated the relationship between stress-related mental health problems and obsessive-compulsive personality disorder (OCPD). Similarly, little research has focused on the moderating effect of OCPD on recovery in clinical patients with stress-related mental health problems. The general aim of this study was to investigate the prevalence of OCPD and the associations between OCPD and level of burnout, anxiety, and depression symptoms, during a 7-years follow-up in a clinical longitudinal sample of female patients with stress-related exhaustion. METHOD: The included patients (n = 84) were referred to a specialist outpatient clinic for patients with stress-related exhaustion between 2006 and 2011. Data was collected at the initial examination and during a 7-year treatment follow-up. RESULTS: OCPD was the most common personality disorder in the present clinical sample, with 40% of patients fulfilling the criteria. There was a significant association between OCPD and the degree of burnout symptoms as well as the degree of depression, both at baseline and during the 7-year follow-up. No significant association between OCPD and levels of anxiety was observed. CONCLUSION: The results support the hypothesis that there might be an association between OCPD and stress-related exhaustion, including preservation of symptoms over time. OCPD and its related traits, such as perfectionism, may be important factors to consider when constructing effective treatment and rehabilitation plans for these patients.


Assuntos
Transtorno Obsessivo-Compulsivo , Perfeccionismo , Humanos , Feminino , Transtorno da Personalidade Compulsiva/epidemiologia , Transtorno da Personalidade Compulsiva/psicologia , Transtorno Obsessivo-Compulsivo/epidemiologia , Transtorno Obsessivo-Compulsivo/diagnóstico , Prevalência , Esgotamento Psicológico
2.
J Transl Med ; 20(1): 121, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35287672

RESUMO

BACKGROUND: Safety, tolerability and efficacy of granulocyte colony-stimulating factor (G-CSF) for mobilization of hematopoietic stem and progenitor cells (HSPCs) from healthy donors have been conclusively demonstrated. This explicitly includes, albeit for smaller cohorts and shorter observation periods, biosimilar G-CSFs. HSPC donation is non-remunerated, its sole reward being "warm glow", hence harm to donors must be avoided with maximal certitude. To ascertain, therefore, long-term physical and mental health effects of HSPC donation, a cohort of G-CSF mobilized donors was followed longitudinally. METHODS: We enrolled 245 healthy volunteers in this bi-centric long-term surveillance study. 244 healthy volunteers began mobilization with twice-daily Sandoz biosimilar filgrastim and 242 underwent apheresis after G-CSF mobilization. Physical and mental health were followed up over a period of 5-years using the validated SF-12 health questionnaire. RESULTS: Baseline physical and mental health of HSPC donors was markedly better than in a healthy reference population matched for ethnicity, sex and age. Physical, but not mental health was sharply diminished at the time of apheresis, likely due to side effects of biosimilar G-CSF, however had returned to pre-apheresis values by the next follow-up appointment after 6 months. Physical and mental health slightly deteriorated over time with kinetics reflecting the known effects of aging. Hence, superior physical and mental health compared to the general healthy non-donor population was maintained over time. CONCLUSIONS: HSPC donors are of better overall physical and mental health than the average healthy non-donor. Superior well-being is maintained over time, supporting the favorable risk-benefit assessment of volunteer HSPC donation. Trial registration National Clinical Trial NCT01766934.


Assuntos
Mobilização de Células-Tronco Hematopoéticas , Saúde Mental , Fator Estimulador de Colônias de Granulócitos/farmacologia , Voluntários Saudáveis , Células-Tronco Hematopoéticas , Humanos
3.
Neurobiol Dis ; 115: 167-181, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29630989

RESUMO

TAR DNA-binding protein 43 (TDP43) plays a significant role in familiar and sporadic amyotrophic lateral sclerosis (ALS). The diverse postulated mechanisms by which TDP43 mutations cause the disease are not fully understood. Human wildtype and TDP43 S393L and G294V mutant spinal motor neuron cultures were differentiated from patient-derived iPSCs. Mutant hTDP43 and wildtype motor neuron cultures did not differ in neuron differentiation capacity during early maturation stage. During aging we detected a dramatic neurodegeneration including neuron loss and pathological neurofilament abnormalities only in TDP43 mutant cultures. Additionally mitochondria and lysosomes of aging spinal motor neurons revealed robust TDP43 mutation dependent abnormal phenotypes in size, shape, speed and motility which all appeared without TDP43 mislocalization or aggregation formation. Furthermore, D-sorbitol - known to induce stress granules and cytoplasmic mislocalization of TDP43 - rescued axonal trafficking phenotypes without signs of TDP43 mislocalization or aggregation formation. Our data indicate TDP43 mutation-dependent but cytosolic aggregation-independent mechanisms of motor neuron degeneration in TDP43 ALS.


Assuntos
Envelhecimento/patologia , Proteínas de Ligação a DNA , Neurônios Motores/patologia , Mutação , Doenças Neurodegenerativas/patologia , Organelas/patologia , Agregados Proteicos , Envelhecimento/genética , Transporte Biológico/fisiologia , Células Cultivadas , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Feminino , Células HEK293 , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Masculino , Pessoa de Meia-Idade , Neurônios Motores/metabolismo , Mutação/genética , Doenças Neurodegenerativas/genética , Organelas/genética , Organelas/metabolismo , Agregados Proteicos/genética
4.
J Phys Chem A ; 118(3): 561-72, 2014 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-24383464

RESUMO

The reactivity of diatomic titanium with nitrous oxide has been studied in solid neon. Two molecules with the same Ti2-N2O stoichiometry are identified from concentration, temperature, and irradiation effects. The more stable one is characterized by five fundamental vibrational transitions located below 1000 cm(-1), the high frequency one at 946 cm(-1) corresponding to a pure TiO stretching mode. Its structure, a rhombus OTiNTiN with the extra O atom fixed on one Ti, is confirmed by quantum chemical calculations, at the CCSD(T) level, which predict a Cs structure in the singlet state with a Ti-O bond length close to 1.66 Å, two nonequivalent Ti-N distances close to 1.94 and 1.75 Å, and a OTiTi angle of 119.2°. The second Ti2-N2O molecule, only observed after annealing, is easily converted into the first one upon irradiation above 12 000 cm(-1) and its kinetics of photoconversion allows vibrational transitions to be identified. The strongest one located at 2123.4 cm(-1) characterizes an N-N stretching mode. Corresponding ab initio calculations complete this picture with details on the electronic structure and allow us to identify a most adequate density functional to describe the spectroscopic properties of the studied species in a simpler broken-symmetry open-shell DFT context. The theoretical results predict the existence of a metastable product OTi2N2 and correctly account for the observed spectra of the various isotopic varieties.

6.
J Chem Phys ; 129(16): 164106, 2008 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-19045246

RESUMO

Starting from localized bond or lone-pair Hartree-Fock molecular orbitals, one may define contracted doubly excited functions for each pair of bond molecular orbitals. These functions are obtained from local single- and double-configuration interaction (CISD) of moderate size. Then one may build a contracted CISD matrix for the whole molecule, spanned by the Hartree-Fock determinant and these contracted doubly excited functions, the number of which is indeed moderate, as scaling at most as the square of the number of bonds. The calculation of the off-diagonal elements of this matrix is straightforward. Its diagonalization provides an upper bound to the lowest CISD eigenvalue. The well-known size-consistency error may be overcome through self-consistent dressings such as coupled-electron pair approximations, and cutoff criteria will lead to linear scaling. Numerical tests on a series of covalent and ionic systems show that the results are very close to that of coupled-cluster calculations. Possible improvements of this already efficient algorithm are suggested.

7.
J Chem Phys ; 128(24): 244301, 2008 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-18601326

RESUMO

For the first time the coexistence of a sigma- and a pi-complex in the C(4)H(4)O:HCl system has been observed, in the same supersonic expansion of a molecular jet seeded with argon (or helium) or in a flow-cooled cell at 240 K. This is an exception to the third of the Legon-Miller rules which claims the sigma-structure to be the only one to exist. On the grounds of energetic considerations and band contour simulations, two observed bands at 2787.7 and 2795.5 cm(-1) of the nu(s) HCl stretching frequency are assigned to the two complexes, recorded as Fourier transform infrared spectra with a resolution between 0.2 and 0.5 cm(-1). Complementary calculations show that the use of the standard second-order Moller-Plesset perturbation theory may be erroneous for such a complex, due of the overestimation of the dispersion contribution with respect to the electrostatic term. It is finally established that only a balanced version of the second-order Moller-Plesset perturbation method, spin-component scaled-MP2, or a higher level of theory like a coupled-cluster approach, can provide a reliable energetic analysis for this complex.

8.
Int J Hematol ; 87(3): 289-97, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18317881

RESUMO

We present a case report of a successful high-dose melphalan therapy and autologous stem cell transplantation without the use of allogeneic blood product support in a 70-year-old patient suffering from multiple myeloma. Based on the experience in this case and thorough evaluation of the literature, we consider pre-transplant Hb level of 11-12 g/dl, platelet count higher than 70/nl, good WHO performance status of two and lower and informed consent as important eligibility criteria. During cytopenia recommended supportive measures include growth factor support with erythropoietin and G-CSF, p.o. iron treatment as well as prophylactic use of anti-fibrinloytic agents. Furthermore we discuss additional options that might be considered depending on the individual factors as e.g. pre-transplant collection and cryoconservation of autologous platelet concentrates. Moreover, an analysis of socio-economic issues regarding this procedure is presented. We conclude that allogeneic blood product free transplantation is a feasible procedure that can be offered to the patients belonging to distinct religious groups refusing allogeneic blood products as Jehovás Witnesses and patients presenting other contraindications for transfusions.


Assuntos
Testemunhas de Jeová , Mieloma Múltiplo/terapia , Transplante de Células-Tronco de Sangue Periférico , Condicionamento Pré-Transplante , Idoso , Criopreservação , Humanos , Masculino , Mieloma Múltiplo/tratamento farmacológico , Plaquetoferese , Indução de Remissão , Transplante Autólogo
9.
Can J Physiol Pharmacol ; 84(2): 221-6, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16900948

RESUMO

The combination of phototoxic drugs and ultraviolet (UV) radiation can trigger the release of proinflammatory cytokines. The present study measured the ability of sunscreens to prevent cytokine secretion in human keratinocytes following cotreatment of these cells with a known photoreactive drug and UVA. Keratinocytes were treated for 1 h with increasing concentrations of lomefloxacin (LOM) or norfloxacin (NOR), exposed to 15 J/cm2 UVA, and incubated for 24 h. NOR, owing to the absence of a fluorine atom in position 8, was non-phototoxic and used as a negative control. Cell viability and the release of 3 cytokines were assessed, namely interleukin-1alpha (IL-1alpha), interleukin-6 (IL-6), and tumour necrosis factor-alpha (TNF-alpha). The measurement of these cytokines may be a useful tool for detecting photoreactive compounds. To measure their ability to prevent cytokine secretion, various sunscreens were inserted between the UVA source and the cells. Treatment with NOR, NOR plus UVA, or LOM had no effect on the cells. LOM plus UVA, however, had an effect on cell viability and on cytokine secretion. IL-1alpha levels increased with LOM concentration. The release of TNF-alpha and IL-6 followed the same pattern at lower concentrations of LOM but peaked at 15 micromol/L and decreased at higher concentrations. Sunscreens protected the cells from the effects of LOM plus UVA, as cell viability and levels of cytokines remained the same as in the control cells. In conclusion, the application of broad-spectrum sunscreen by individuals exposed to UVA radiation may prevent phototoxic reactions initiated by drugs such as LOM.


Assuntos
Citocinas/metabolismo , Fluoroquinolonas/toxicidade , Mediadores da Inflamação/antagonistas & inibidores , Queratinócitos/efeitos dos fármacos , Quinolonas/toxicidade , Protetores Solares/farmacologia , Raios Ultravioleta/efeitos adversos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Sobrevivência Celular/efeitos da radiação , Células Cultivadas , Citocinas/antagonistas & inibidores , Citocinas/efeitos da radiação , Dermatite Fototóxica/prevenção & controle , Relação Dose-Resposta a Droga , Relação Dose-Resposta à Radiação , Humanos , Mediadores da Inflamação/metabolismo , Mediadores da Inflamação/efeitos da radiação , Queratinócitos/metabolismo , Queratinócitos/efeitos da radiação
10.
Laryngorhinootologie ; 84(11): 822-8, 2005 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-16358189

RESUMO

BACKGROUND: The trifunctional bi-specific antibody Removab bridges and activates CD3 positive T cells to EpCAM on carcinoma cells and simultaneously binds to an accessory immune cell, thus inducing tumor cell lysis. Following intravenous application, Removab may induce cytokine-related side effects resulting in a sepsis like syndrom. It was questioned, if peripheral mononuclear blood cells (PBMN) already opsonized with Removab could retain antitumor activity and induce less cytokine release than the mere antibody. METHODS: PBMN of patients with head and neck cancer were incubated with Removab and the released cytokines were washed out. Then the Removab-opsonized PBMN were coincubated with genuine tumor cells of the same patient on a chorioallantois membrane for 24 h (T 24) and 48 h (T 48). Tumor cells coincubated with Cisplatin or solely cell culture medium served as control. RESULTS: Coincubation of tumor cells with opsonized PBMN resulted in a 32 % decrease of viable cells at T 24 and a 37 % decrease at T 48, whereas viable cells increased by 10 % at T 24 or 3 % at T 48 when incubated with medium alone (p < 0.05). This tumor cytotoxicity was similar to that of Cisplatin (35 % at T 24/37 % at T 48). CONCLUSION: In an autologous human ex vivo tumor system, Removab-opsonized PBMN induce tumor cell lysis with significantly reduced cytokine release after i. v. application.


Assuntos
Anticorpos Biespecíficos/farmacologia , Anticorpos Monoclonais/farmacologia , Antineoplásicos/farmacologia , Complexo CD3/imunologia , Carcinoma de Células Escamosas/imunologia , Citocinas/sangue , Fatores Imunológicos/farmacologia , Ativação Linfocitária/efeitos dos fármacos , Neoplasias Otorrinolaringológicas/imunologia , Linfócitos T/efeitos dos fármacos , Células Tumorais Cultivadas/efeitos dos fármacos , Adulto , Idoso , Animais , Antígenos de Neoplasias/imunologia , Complexo CD3/efeitos dos fármacos , Moléculas de Adesão Celular/imunologia , Sobrevivência Celular/efeitos dos fármacos , Embrião de Galinha , Testes Imunológicos de Citotoxicidade , Molécula de Adesão da Célula Epitelial , Feminino , Humanos , Infusões Intravenosas , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Neutrófilos/efeitos dos fármacos , Neutrófilos/imunologia , Receptores Imunológicos/efeitos dos fármacos , Receptores Imunológicos/imunologia , Técnica de Janela Cutânea , Linfócitos T/imunologia , Células Tumorais Cultivadas/imunologia
11.
Int J Oncol ; 25(4): 841-8, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15375531

RESUMO

Removab is a trifunctional bispecific antibody which can bridge CD3+ T cells and epithelial cell adhesion molecule positive (EpCAM+) tumor cells, and binds with its Fc fragment to antigen presenting cells. To explore a new approach for the treatment of patients with carcinoma of the upper aerodigestive tract, we investigated whether Removab can induce specific cellular responses to the EpCAM+ carcinoma cell line BHY. Particular emphasis was put on the opsonization of peripheral blood mononuclear cells (PBMN) with respect to clinical application. Tumor cells and allogeneic PBMN of healthy volunteers were incubated with or without Removab. In a third group, PBMN were opsonized with Removab and washed before incubation with tumor cells. Inverse microscopy, ELISPOT, flow cytometry analysis and cytotoxicity assays on the chorioallantois membrane (CAM) were performed. In comparison with PBMN alone, opsonization with Removab resulted in: a) activation of CD83+ antigen presenting cells, b) secretion of interferon gamma, and c) granzyme B mediated lysis of targeted BHY cells by EpCAM specific CD8+ T cells. The secretion of tumor necrosis factor alpha, interferon gamma and interleukin-2 by opsonized PBMN was significantly reduced after 24 h. Washed opsonized PBMN maintained their lytic activity against tumor cells as tested on the CAM. Removab is an appropriate agent for the therapeutic amplification of T cell responses against EpCAM+ tumor cells by opsonization of PBMN without putting patients at risk for severe adverse events caused by a cytokine storm.


Assuntos
Anticorpos Biespecíficos/uso terapêutico , Antígenos de Neoplasias/imunologia , Complexo CD3/imunologia , Moléculas de Adesão Celular/imunologia , Neoplasias Orofaríngeas/terapia , Fagocitose , Linfócitos T Citotóxicos/imunologia , Linhagem Celular Tumoral , Células Dendríticas/fisiologia , Molécula de Adesão da Célula Epitelial , Humanos , Interferon gama/biossíntese , Ativação Linfocitária , Neoplasias Orofaríngeas/patologia
12.
Blood ; 95(9): 2954-9, 2000 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-10779445

RESUMO

The objective of this study was to investigate whether leukocytes could be recruited by rolling leukocytes in a human whole blood model system. In all experiments, either neutrophils, whole blood, or diluted blood was perfused over immobilized E-selectin. With isolated neutrophils (2 x 10(5)/mL), the free-flowing neutrophils were captured by attached neutrophils to form secondary interactions that resulted in lines of rolling leukocytes. These secondary tethers accounted for 50% to 60% of all interactions and were eliminated by an L-selectin antibody, which also eliminated the lines of rolling leukocytes. Perfusion of whole blood or diluted blood revealed no lines of rolling leukocytes. The addition of red blood cells to isolated neutrophils either in a 1000:1 or a 10:1 ratio also inhibited lines of rolling leukocytes. Leukocytes were fluorescently labeled with rhodamine-6G so that leukocyte-leukocyte interactions could be studied in whole blood. A small number of secondary tethers (less than 20%) occurred and could be reduced by more than 80% with an L-selectin antibody. However, the overall impact on leukocyte recruitment was negligible. Similar experiments were performed using murine whole blood or isolated murine leukocytes. In the absence of red blood cells, murine leukocytes also formed lines of rolling leukocytes on E-selectin, and secondary tethers accounted for 50% of total interactions. However, when murine blood (diluted 1:5 with buffer) was perfused over E-selectin, secondary tethers accounted for only 13% of total interactions. These interactions were completely absent when blood was used from L-selectin-deficient mice. These data demonstrate for the first time that the importance of L-selectin-dependent leukocyte-leukocyte interactions is greatly reduced in whole blood and does not enhance overall recruitment of leukocytes in this physiologic milieu. (Blood. 2000;95:2954-2959)


Assuntos
Adesão Celular/fisiologia , Selectina L/fisiologia , Leucócitos/fisiologia , Neutrófilos/fisiologia , Animais , Comunicação Celular , Humanos , Técnicas In Vitro , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
15.
Circ Res ; 83(11): 1124-31, 1998 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-9831707

RESUMO

The objective of this study was to determine whether endogenous IL-10 is capable of regulating hemodynamic parameters, leukocyte recruitment, and microvascular permeability in response to endotoxin. Intravital microscopy was used to examine hemodynamic parameters, leukocyte rolling and adhesion, and microvascular permeability in cremasteric postcapillary venules in wild-type mice and in IL-10-deficient (IL-10(-/-)) mice exposed to lipopolysaccharide (LPS). Doses of LPS (3 or 30 microg/kg, IV), which did not reduce blood pressure and minimally altered microvascular hemodynamic factors in wild-type mice, caused significant reductions in these parameters in IL-10(-/-) mice, demonstrating at least a 10-fold increased sensitivity in IL-10(-/-) mice to LPS-induced hemodynamic alterations. Furthermore, in response to LPS (30 microg/kg, IV), leukocyte rolling, adhesion, and fluorescein isothiocyanate-albumin extravasation were increased in the IL-10(-/-) mice. Antibody blockade experiments showed that in both types of mice, leukocyte rolling was mediated by E-selectin and P-selectin. Leukocyte accumulation into other tissues, such as lung, also was enhanced greatly in IL-10(-/-) mice. This was specific to endotoxin, because acute chemotactic stimuli including N-formyl-methionyl-leucyl-phenylalanine elicited similar responses in IL-10(-/-) and wild-type mice. These results suggest that endogenous IL-10 may be a homeostatic regulator of hemodynamic parameters, leukocyte-endothelial cell interactions, and microvascular dysfunction in response to endotoxin and provide potential mechanisms to explain the protective effect of IL-10 against LPS-induced mortality.


Assuntos
Endotélio Vascular/citologia , Endotoxemia/fisiopatologia , Hemodinâmica/fisiologia , Interleucina-10/fisiologia , Leucócitos/citologia , Animais , Anticorpos/farmacologia , Pressão Sanguínea , Permeabilidade Capilar/fisiologia , Adesão Celular/efeitos dos fármacos , Comunicação Celular/fisiologia , Movimento Celular/efeitos dos fármacos , Selectina E/imunologia , Lipopolissacarídeos/farmacologia , Pulmão/efeitos dos fármacos , Camundongos , Camundongos Mutantes , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Selectina-P/imunologia , Proteínas/farmacocinética , Estresse Mecânico
16.
J Exp Med ; 188(11): 2181-6, 1998 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-9841931

RESUMO

Although there is considerable evidence implicating a role for CD43 (leukosialin) in leukocyte cell-cell interactions, its precise function remains uncertain. Using CD43-deficient mice (CD43(-/-)) and intravital microscopy to directly visualize leukocyte interactions in vivo, we investigated the role of CD43 in leukocyte-endothelial cell interactions within the cremasteric microcirculation under flow conditions. Our studies demonstrated significantly enhanced leukocyte rolling and adhesion after chemotactic stimuli in CD43(-/-) mice compared with wild type mice. Using an in vitro flow chamber, we established that the enhanced rolling interactions of CD43(-/-) leukocytes, primarily neutrophils, were also observed using immobilized E-selectin as a substrate, suggesting that passive processes related to steric hindrance or charge repulsion were likely mechanisms. Despite increased adhesion and rolling interactions by CD43(-/-) leukocytes, we uncovered a previously unrecognized impairment of CD43(-/-) leukocytes to infiltrate tissues. Oyster glycogen-induced neutrophil and monocyte infiltration into the peritoneum was significantly reduced in CD43(-/-) mice. In response to platelet activating factor, CD43(-/-) leukocytes were impaired in their ability to emigrate out of the vasculature. These results suggest that leukocyte CD43 has a dual function in leukocyte-endothelial interactions. In addition to its role as a passive nonspecific functional barrier, CD43 also facilitates emigration of leukocytes into tissues.


Assuntos
Antígenos CD , Movimento Celular/imunologia , Endotélio Vascular/imunologia , Leucócitos/imunologia , Sialoglicoproteínas/fisiologia , Animais , Adesão Celular/imunologia , Comunicação Celular/imunologia , Endotélio Vascular/patologia , Leucócitos/patologia , Leucossialina , Camundongos
17.
Blood ; 92(12): 4691-9, 1998 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-9845535

RESUMO

The objective of this study was to determine if vascular cell adhesion molecule (VCAM-1), E-selectin, and P-selectin could selectively recruit leukocyte subpopulations, and whether this was affected by shear force or adhesion molecule concentration. Cover slips coated with purified adhesion molecules were incorporated into laminar flow chambers. Whole human blood was perfused for 5 minutes over these cover slips at relative shear forces of 2 to 40 dynes/cm2. Chasing the whole blood with buffer permitted visualization of leukocyte-substratum interactions. Leukocytes were observed to roll on and adhere to VCAM-1 at shears between 2 and 15 dynes/cm2. As assessed by cover slip staining, the majority of these cells were lymphocytes, but eosinophils, monocytes, and, surprisingly, neutrophils were also recruited, events inhibitable by anti-4-integrin antibody (HP1/2). Neutrophils were effectively recruited onto the selectins, with interactions occurring at shears as high as 30 and 40 dynes/cm2 for E- and P-selectin respectively. Eosinophils had high affinity for P- but not E-selectin. Mononuclear cells did not have high affinity for either selectin, but interacted avidly with VCAM-1. Antibodies against P-selectin (G1) and E-selectin (ES-1) completely blocked interactions on these substrates. Reducing the concentration of adhesion molecules did not appreciably change recruitment patterns except for VCAM-1, where neutrophils were no longer recruited. The novel use of whole blood in flow chambers shows a partial selectivity of selectins and VCAM-1 for certain subpopulations of leukocytes under varying physiologic shear conditions.


Assuntos
Fenômenos Fisiológicos Sanguíneos , Moléculas de Adesão Celular/fisiologia , Endotélio Vascular/fisiologia , Leucócitos/fisiologia , Soluções Tampão , Adesão Celular/fisiologia , Selectina E/metabolismo , Selectina E/fisiologia , Eosinófilos/fisiologia , Gravitação , Humanos , Subpopulações de Linfócitos/fisiologia , Monócitos/fisiologia , Neutrófilos/fisiologia , Selectina-P/metabolismo , Selectina-P/fisiologia , Perfusão , Estresse Mecânico , Molécula 1 de Adesão de Célula Vascular/metabolismo , Molécula 1 de Adesão de Célula Vascular/fisiologia
18.
AIDS Res Hum Retroviruses ; 14(13): 1199-203, 1998 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-9737591

RESUMO

In most parts of Europe only a limited number of sporadic cases of HTLV-I infections have been identified. So far, the few cases found in Germany have always been linked to individuals with relations to endemic areas. Here we report the first HTLV-I infection from a German ATL patient without any known risk for HTLV-I infection and with no relations to known endemic areas. The DNA sequence of the provirus was determined, and a phylogenetic analysis based on the LTR sequence established a close relationship with HTLV-I sequences previously found in two Romanian patients. Our data suggest the existence of a previously unrecognized cluster of HTLV-I infections in southeastern or central Europe.


Assuntos
Infecções por HTLV-I/virologia , Vírus Linfotrópico T Tipo 1 Humano/genética , Vírus Linfotrópico T Tipo 1 Humano/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Adulto , DNA Viral/análise , Feminino , Alemanha/epidemiologia , Infecções por HTLV-I/epidemiologia , Humanos , Leucemia-Linfoma de Células T do Adulto/virologia , Filogenia , Análise de Sequência de DNA
19.
J Clin Invest ; 101(11): 2497-505, 1998 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-9616221

RESUMO

Inhaled nitric oxide (NO) is being used more and more in intensive care units as a modality to improve the outcome of patients with pulmonary complications. Our objective was to demonstrate that inhaled NO could impact upon a distally inflamed microvasculature-improving perfusion, leukocyte adhesive interactions, and endothelial dysfunction. Using intravital microscopy to visualize ischemia/reperfusion of postcapillary venules, we were able to demonstrate that the reduction in perfusion, the dramatic increase in leukocyte rolling, adhesion, and emigration, and the endothelial dysfunction could all be significantly abrogated with 80 ppm, but not 20 ppm inhaled NO. Perfusing whole blood directly over an inert P-selectin and CD18 ligand substratum incorporated in a flow chamber recruited the same number of rolling and adhering leukocytes from NO-ventilated and non-NO-ventilated animals, suggesting that inhaled NO was not directly affecting leukocytes. To demonstrate that inhaled NO was actually reaching the peripheral microvasculature in vivo, we applied a NO synthase inhibitor locally to the feline mesentery and demonstrated that the vasoconstriction, as well as leukocyte recruitment, were essentially abolished by inhaled NO, suggesting that a NO-depleted peripheral microvasculature could be replenished with inhaled NO in vivo. Finally, inhaled NO at the same concentration that was effective in ischemia/reperfusion did not affect vascular alterations, leukocyte recruitment, and endothelial dysfunction associated with endotoxemia in the feline mesentery. In conclusion, our data for the first time demonstrate a role for inhaled NO as a therapeutic delivery system to the peripheral microvasculature, showing tremendous efficacy as an antiadhesive, antivasoconstrictive, and antipermeabilizing molecule in NO-depleted tissues, but not normal microvessels or vessels that have an abundance of NO (LPS-treated). The notion that blood borne molecules have NO carrying capacity is conceptually consistent with our observations.


Assuntos
Endotélio Vascular/efeitos dos fármacos , Isquemia/tratamento farmacológico , Leucócitos/efeitos dos fármacos , Microcirculação/efeitos dos fármacos , Óxido Nítrico/administração & dosagem , Traumatismo por Reperfusão/tratamento farmacológico , Administração por Inalação , Animais , Gatos , Adesão Celular/efeitos dos fármacos , Comunicação Celular/efeitos dos fármacos , Endotélio Vascular/citologia , Hemodinâmica/efeitos dos fármacos
20.
FASEB J ; 11(12): 955-64, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9337148

RESUMO

Nitric oxide (NO) from constitutive NO synthase (NOS) has been postulated to be a homeostatic regulator of leukocyte-endothelial cell interactions. By contrast, the inducible NO synthase (iNOS) isoform has been invoked as a potential pathogenic enzyme in numerous inflammatory diseases. The objective of this study was to determine whether the iNOS isoform is also capable of functioning as a regulator of leukocyte recruitment. Mice received endotoxin (LPS, 30 microg/kg, i.v.); 2-4 h later, intravital microscopy was used to examine leukocyte rolling and adhesion in postcapillary venules of the cremaster muscle and the sinusoids and postsinusoidal venules of the hepatic microcirculation. Leukocyte recruitment into the lung was also examined. RT-PCR confirmed that this treatment induced iNOS mRNA expression in wild-type mice as early as 2 h after LPS treatment. Between 2 and 4 h after LPS administration, the number of rolling and adherent leukocytes in cremasteric postcapillary venules and of adherent cells in liver postsinusoidal venules of iNOS-deficient mice were significantly higher than in wild-type mice. Leukocyte accumulation in the lung (measured by myeloperoxidase assay) was also significantly elevated in iNOS-deficient animals. These effects could not be attributed to differences in systemic blood pressure, shear rates, circulating leukocyte numbers, or baseline levels of rolling and adhesion because these parameters were not different between the two groups. To establish whether the differences in leukocyte recruitment were related to the leukocytes per se, perfusion of iNOS+/+ or iNOS-/- septic blood over purified E-selectin (using parallel plate flow chambers) revealed much larger recruitment of iNOS-/- leukocytes. These results suggest that iNOS induced in response to LPS releases NO that is capable of reducing leukocyte accumulation by affecting leukocytes directly and raises the possibility that induction of iNOS is a homeostatic regulator for leukocyte recruitment.


Assuntos
Quimiotaxia de Leucócito , Endotélio Vascular/fisiopatologia , Endotoxemia/fisiopatologia , Leucócitos/fisiologia , Microcirculação/fisiopatologia , Óxido Nítrico Sintase/biossíntese , Óxido Nítrico Sintase/deficiência , Transcrição Gênica , Análise de Variância , Animais , Pressão Sanguínea , Endotélio Vascular/fisiologia , Endotoxemia/enzimologia , Endotoxinas , Indução Enzimática , Selectina L/biossíntese , Selectina L/sangue , Lipopolissacarídeos/toxicidade , Fígado/enzimologia , Pulmão/enzimologia , Camundongos , Camundongos Knockout , Microcirculação/fisiologia , Músculo Esquelético/enzimologia , Óxido Nítrico Sintase/genética , Peroxidase/metabolismo , Reação em Cadeia da Polimerase , RNA Mensageiro/biossíntese
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