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1.
J Neural Transm (Vienna) ; 129(4): 387-394, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35306617

RESUMO

Locus Coeruleus (LC) is the main noradrenergic nucleus of the brain, which is involved in many physiological functions including cognition; its impairment may be crucial in the neurobiology of a variety of brain diseases. Locus Coeruleus-Magnetic Resonance Imaging (LC-MRI) allows to identify in vivo LC in humans. Thus, a variety of research teams have been using LC-MRI to estimate LC integrity in normal aging and in patients affected by neurodegenerative disorders, where LC integrity my work as a biomarker. A number of variations between LC-MRI studies exist, concerning post-acquisition analysis and whether this had been performed within MRI native space or in ad hoc-built MRI template space. Moreover, the reproducibility and reliability of this tool is still to be explored. Therefore, in the present study, we analyzed a group of neurologically healthy, cognitively intact elderly subjects, using both a native space- and a template space-based LC-MRI analysis. We found a good inter-method agreement, particularly considering the LC Contrast Ratio. The template space-based approach provided a higher spatial resolution, lower operator-dependency, and allowed the analysis of LC topography. Our ad hoc-developed LC template showed LC morphological data that were in line with templates published very recently. Remarkably, present data significantly overlapped with a recently published LC "metaMask", that had been obtained by averaging the results of a variety of previous LC-MRI studies. Thus, such a template space-based approach may pave the way to a standardized LC-MRI analysis and to be used in future clinic-anatomical correlations.


Assuntos
Locus Cerúleo , Imageamento por Ressonância Magnética , Idoso , Envelhecimento , Humanos , Locus Cerúleo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Reprodutibilidade dos Testes
2.
Eur J Appl Physiol ; 121(1): 297-306, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33057877

RESUMO

PURPOSE: High altitude results in lower barometric pressure and hence partial pressure of O2 decrease can lead to several molecular and cellular changes, such as generation of reactive oxygen species (ROS). Electron Paramagnetic Resonance technique was adopted in the field, to evaluate the effects of acute and sub-acute hypobaric hypoxia (HH) on ROS production by micro-invasive method. Biological biomarkers, indicators of oxidative stress, renal function and inflammation were investigated too. METHODS: Fourteen lowlander subjects (mean age 27.3 ± 5.9 years) were exposed to HH at 3269 m s.l. ROS production, related oxidative damage to cellular components, systemic inflammatory response and renal function were determined through blood and urine profile performed at 1st, 2nd, 4th, 7th, and 14th days during sojourn. RESULTS: Kinetics of changes during HH exposition showed out significant (range p < 0.05-0.0001) increases that at max corresponds to 38% for ROS production rate, 140% for protein carbonyl, 44% for lipid peroxidation, 42% for DNA damage, 200% for inflammatory cytokines and modifications in renal function (assessed by neopterin concentration: 48%). Conversely, antioxidant capacity significantly (p < 0.0001) decreased - 17% at max. CONCLUSION: This 14 days in-field study describes changes of oxidative-stress biomarkers during HH exposure in lowlanders. The results show an overproduction of ROS and consequent oxidative damage to protein, lipids and DNA with a decrease in antioxidant capacity and the involvement of inflammatory status and a transient renal dysfunction. Exposure at high altitude induces a hypoxic condition during acute and sub-acute phases accompanied by molecular adaptation mechanism indicating acclimatization.


Assuntos
Doença da Altitude/metabolismo , Estresse Oxidativo , Adulto , Doença da Altitude/sangue , Doença da Altitude/urina , Citocinas/sangue , Dano ao DNA , Feminino , Hemoglobinas/metabolismo , Humanos , Masculino , Neopterina/urina , Carbonilação Proteica
5.
Sci Rep ; 8(1): 5716, 2018 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-29632391

RESUMO

Ethology has shown that animal groups or colonies can perform complex calculation distributing simple decision-making processes to the group members. For example ant colonies can optimize the trajectories towards the food by performing both a reinforcement (or a cancellation) of the pheromone traces and a switch from one path to another with stronger pheromone. Such ant's processes can be implemented in a photonic hardware to reproduce stigmergic signal processing. We present innovative, completely integrated X-junctions realized using solitonic waveguides which can provide both ant's decision-making processes. The proposed X-junctions can switch from symmetric (50/50) to asymmetric behaviors (80/20) using optical feedbacks, vanishing unused output channels or reinforcing the used ones.


Assuntos
Formigas/fisiologia , Comportamento Animal/fisiologia , Feromônios/metabolismo , Animais , Formigas/metabolismo , Tomada de Decisões , Retroalimentação Fisiológica , Reforço Psicológico , Aprendizagem Espacial
7.
Acta Otorhinolaryngol Ital ; 37(3): 201-206, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28516963

RESUMO

Oral FEES (O-FEES) is an endoscopic procedure conceived to directly visualise the oral phase of swallowing. In the perspective of clinical use, the feasibility, safety and acceptability of O-FEES has been evaluated. Subsequently, the procedure was compared with the radiological gold standard. The acceptability of O-FEES was compared to that of FEES using a 10 point questionnaire submitted to a sample of 52 outpatients complaining of swallowing disorders. Repeated measure analysis of variance (rm-ANOVA) models were used to test the mean difference of acceptability in the same subjects after FEES and O-FEES. Subsequently, another sample of 8 male outpatients underwent a simultaneous O-FEES and videofluoroscopic study (VFSS). The inter-rater reliability using 10 radiological landmarks, compared to O-FEES, was blindly determined between two raters. Inter-rater agreement between the two judges for O-FEES and VFSS scores was assessed with the single score intra-class correlation coefficient (ICC). Differences between FEES and O-FEES answers for each question and among all the items considered overall were statistically significant (rm-ANOVA; F-statistic p < 0.001). The inter-rater agreement concerning endoscopic and radiological evaluations between the two raters showed strong values of intra-class correlation coefficient (ICC) (95% confidence interval): 0.875 (0.373-0.979) and 0.921 (0.542-0.986), respectively. The Bland-Altman test showed a bias of -0.24 (95% limits of agreement; -1.77 to +1.19), which suggests that both methods produced almost identical results. In clinical practice and compared with FEES, O-FEES is a well tolerated and safe procedure. Compared with the radiological gold standard, O-FEES offers reliable information about oral preparation and oral propulsion of the bolus.


Assuntos
Transtornos de Deglutição/fisiopatologia , Deglutição , Endoscopia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Adulto Jovem
8.
Acta Otorhinolaryngol Ital ; 36(5): 395-402, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27958600

RESUMO

The purpose of this study was to compare videofluoroscopy (VFS), fiberoptic endoscopic evaluation of swallowing (FEES) and oro-pharyngo- oesophageal scintigraphy (OPES) with regards to premature spillage, post-swallowing residue and aspiration to assess the reliability of these tests for detection of oro-pharyngeal dysphagia. Sixty patients affected with dysphagia of various origin were enrolled in the study and submitted to VFS, FEES and OPES using a liquid and semi-solid bolus. As a reference, we used VFS. Both the FEES and the OPES showed good sensitivity with high overall values (≥ 80% and ≥ 90% respectively). The comparison between FEES vs VFS concerning drop before swallowing showed good specificity (84.4% for semi-solids and 86.7% for liquids). In the case of post-swallowing residue, FEES vs VFS revealed good overall validity (75% for semi-solids) with specificity and sensitivity well balanced for the semi-solids. OPES vs. VFS demonstrated good sensitivity (88.6%) and overall validity (76.7%) for liquids. The analysis of FEES vs. VFS for aspiration showed that the overall validity was low (≤ 65%). On the other hand, OPES demonstrated appreciable overall validity (71.7%). VFS, FEES and OPES are capable of detecting oro-pharyngeal dysphagia. FEES gave significant results in the evaluation of post-swallowing residues.


Assuntos
Transtornos de Deglutição/diagnóstico por imagem , Transtornos de Deglutição/fisiopatologia , Deglutição , Endoscopia , Feminino , Tecnologia de Fibra Óptica , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Cintilografia , Gravação em Vídeo
9.
Comput Biol Med ; 76: 238-49, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27504744

RESUMO

This paper proposes a method for an automatic extraction of geometric features, related to weight parameters, from 3D facial data acquired with low-cost depth scanners. The novelty of the method relies both on the processing of the 3D facial data and on the definition of the geometric features which are conceptually simple, robust against noise and pose estimation errors, computationally efficient, invariant with respect to rotation, translation, and scale changes. Experimental results show that these measurements are highly correlated with weight, BMI, and neck circumference, and well correlated with waist and hip circumference, which are markers of central obesity. Therefore the proposed method strongly supports the development of interactive, non obtrusive systems able to provide a support for the detection of weight-related problems.


Assuntos
Tecido Adiposo/fisiologia , Peso Corporal/fisiologia , Face/anatomia & histologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Fotogrametria , Adulto Jovem
11.
Eur Heart J Cardiovasc Imaging ; 17(suppl_2): ii45-ii48, 2016 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28415084

RESUMO

BACKGROUND: Strenuous and chronic exercise training can have detrimental effects on cardiac morphology and function. Our aim was to evaluate the cardiac adaptation between 2 different specialties' endurance athletes: marathon runners (M) and ultra-trailers (UT). METHODS: 47 M (age 45±7, men 32; training: 18 (9-53) years*days/week), 41 UT (age 42±9, men 38, training: 30 (15-66) years*days/week) were submitted in rest condition to conventional 2D echocardiography and Speckle-Tracking echo (STE) (Beyond Diogenes 2.0, AMID) during agonistic season and compared with 15 age matched sedentary individuals (S) (age 43±6, men 10). RESULTS: Left ventricle (LV) global longitudinal strain (GLS) and global radial strain (GRS) were increased in M and UT compared to S (see table) without differences in LV anatomy and function. Right ventricle (RV) end-diastolic area (p=0.026), fractional area changing (p=0.008) and RV GLS were increased in UT compared to M. Moreover UT showed larger right atrium (RA) volume compared to M (p=0.03) and S (p=0.003). RA GLS was reduced in UT compared to M while the RA Global Circumferential Strain was significantly increased in UT. After adjusted for age, sex and HR as covariates, UT showed a reduced RA GLS (OR 0.907; CI 0.856-0.961) and increased RV FAC (OR 1.172; CI: 1.044-1.317) compared to M; while when compared to S subjects, UT showed increased RA volume (OR 1.048; CI 1.002-1.096) and RV GLS (OR 0.667; CI 0.490-0.907). CONCLUSION: UT showed higher RV and RA morphological and functional remodeling in comparison with M. 2D-STE is a useful tool to investigate the deformation dynamic in different sport specialties. Further studies will be necessary to clarify the long-term consequences for cardiac health due to myocardial perturbations.MUTSpLV GLS-28.59±3.43*-27.64±4.18*-24.82±4.53<0.05LV GRS69.85±8.94*66.59±11.19*56.27±16.25<0.001RV GLS-25.60±10.54-30.41±4.38*-27.10±4.64<0.05RA GLS37.15±13.4931.65±9.60*35.37±9.99<0.05RA GCS17.46±6.4222.28±8.97*23.37±6.47<0.01.


Assuntos
Ecocardiografia/métodos , Tolerância ao Exercício/fisiologia , Interpretação de Imagem Assistida por Computador , Corrida , Disfunção Ventricular Esquerda/diagnóstico por imagem , Remodelação Ventricular/fisiologia , Adaptação Fisiológica , Adulto , Fatores Etários , Atletas , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valores de Referência , Medição de Risco , Fatores Sexuais , Função Ventricular Direita/fisiologia
12.
Insights Imaging ; 7(2): 233-42, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26596570

RESUMO

OBJECTIVES: To evaluate radiation protection basic knowledge and dose assessment for radiological procedures among Italian radiographers METHODS: A validated questionnaire was distributed to 780 participants with balanced demographic characteristics and geographic distribution. RESULTS: Only 12.1 % of participants attended radiation protection courses on a regular basis. Despite 90 % of radiographers stating to have sufficient awareness of radiation protection issues, most of them underestimated the radiation dose of almost all radiological procedures. About 5 % and 4 % of the participants, respectively, claimed that pelvis magnetic resonance imaging and abdominal ultrasound exposed patients to radiation. On the contrary, 7.0 % of the radiographers stated that mammography does not use ionising radiation. About half of participants believed that radiation-induced cancer is not dependent on age or gender and were not able to differentiate between deterministic and stochastic effects. Young radiographers (with less than 3 years of experience) showed a higher level of knowledge compared with the more experienced radiographers. CONCLUSIONS: There is a substantial need for radiographers to improve their awareness of radiation protection issues and their knowledge of radiological procedures. Specific actions such as regular training courses for both undergraduate and postgraduate students as well as for working radiographers must be considered in order to assure patient safety during radiological examinations. MAIN MESSAGES: • Radiographers should improve their knowledge on radiation protection issues. • Only 12.1 % of participants attended radiation protection courses on a regular basis. • Specific actions must be considered in order to increase knowledge and awareness.

13.
Addict Behav ; 38(4): 2060-7, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23396173

RESUMO

PURPOSE: Psychometric and screening properties of the Cannabis Abuse Screening Test (CAST) and of the Severity Dependence Scale (SDS) were investigated using DSM-IV diagnoses of cannabis dependence (CD) as external criteria. Performance of the SDS and of the CAST were compared. METHODS: Cross-sectional European School Survey Project on Alcohol and Other Drugs (ESPAD) was carried out in Italy in 2009. The sample consisted of 5787 Italian adolescents aged 15-19 who reported cannabis last year use. Uni-dimensionality, internal reliability, external validity, and optimal scaling of the 6 items for CAST and 5 items for SDS were performed. The Munich Composite International Diagnostic Interview (M-CIDI) was used as a gold standard for DSM-IV diagnoses, and all outputs were assessed by 10-fold cross validation procedure. RESULTS: Both scales were uni-dimensional and Cronbach's α was 0.74 for SDS and 0.78 for CAST. High and comparable area under curve (AUC) values indicate a good ability of both scales to discriminate between individuals with and without dependence diagnosis. Based on balanced sensitivity and specificity, the optimal cut-off scores for problematic use disorders were 7 for CAST MCA and 4 for SDS MCA. Both CAST and SDS overestimated CD prevalence. CONCLUSIONS: The CAST and SDS are equally useful for screening for problematic cannabis use disorders. Both clinical and research applications of the scales are possible.


Assuntos
Abuso de Maconha/diagnóstico , Adolescente , Estudos Transversais , Manual Diagnóstico e Estatístico de Transtornos Mentais , Feminino , Humanos , Masculino , Psicometria/instrumentação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Inquéritos e Questionários , Adulto Jovem
14.
J Immunol Methods ; 253(1-2): 253-62, 2001 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-11384686

RESUMO

This protocol describes a simple assay that can be used to study the nature of exposure of antigenic epitopes and antigenic relatedness of different intact, native HIV-1 strains. The assay is based on the principle that mAbs coated on microtiter wells bind to epitopes on the surface of intact, native virions. The bound virion is then lysed to release p24, which is then quantitated (pg/ml) to give a measure of the amount of virion bound to the mAb. High p24 levels released after lysis correlate with high level capture of virions by mAbs, and as such, reflect good exposure of the epitope on the virion. Likewise, binding patterns of a specific mAb with different virus strains reveal information on their antigenic relatedness. In establishing this assay, the nature of exposure of antigenic epitopes and the antigenic relatedness of six intact, native HIV-1 virions of clades A, B, C, D, F and G were examined using anti-HIV-1 mAbs directed at epitopes in the V2, V3, CD4bd and C5 of gp120, and in clusters I and II of the gp41 region. Analysis of the binding data shows that mAbs directed at epitopes in the V3, C5 and gp41 Cluster I region bound best to the viruses examined, suggesting that these are the regions most exposed and conserved on intact, native HIV-1 virions of different clades. Epitopes in the V2 and CD4bd of gp120, and in gp41 cluster II, are not exposed on intact, native virions.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Proteína do Núcleo p24 do HIV/imunologia , HIV-1/imunologia , Anticorpos Monoclonais/imunologia , Células Cultivadas , Sequência Conservada , Epitopos/imunologia , Anticorpos Anti-HIV/imunologia , Proteína gp120 do Envelope de HIV/imunologia , Proteína gp41 do Envelope de HIV/imunologia , Humanos , Especificidade da Espécie , Vírion/imunologia
15.
AIDS Res Hum Retroviruses ; 14 Suppl 3: S247-54, 1998 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9814951

RESUMO

While CD4 and several chemokine receptors are the principal receptors for human immunodeficiency virus type 1 (HIV-1) viruses, other cell membrane proteins also play a role in HIV-1 infection. A large array of host cell-derived membrane proteins, including adhesion molecules, are incorporated into the envelope of HIV-1 virions, and the profile of host cell proteins acquired by the virus depends on the cells used to propagate the virus. The major leukocyte adhesion molecules, such as leukocyte-function associated antigen-1 (LFA-1), intercellular adhesion molecule-1 (ICAM-1), and CD44, retain their biological functions when expressed on the virion surface, and have been shown to increase virus-cell interaction, enhance virus infectivity, and extend the host cell range of the virus. LFA-1 and its ICAM ligands are also necessary for syncytium formation and cell-to-cell transmission of HIV-1. Furthermore, several studies demonstrate that the presence and level of cell-derived adhesion molecules on the surface of HIV-1 virions affect the process by which antibody-mediated virus neutralization occurs and is measured: the level of virus neutralization is influenced by the host cell-derived adhesion molecules present on the virus, and thus, by the type of host cells in which the virus was produced. Adhesion molecules expressed on the target cells used in neutralization assays similarly affect HIV-1 neutralization by virus-specific antibodies. Consistent with these observations is the finding that neutralizing activities of both HIV+ plasma and human anti-gp120 monoclonal antibodies (Mabs) are enhanced by an anti-LFA-1 Mab capable of blocking LFA-1 functions. Hence, LFA-1, ICAM-1, and other cellular adhesion molecules are involved in different stages of HIV-1 infection and profoundly affect HIV-1 neutralization by virus-specific antibodies. These findings illuminate the biology of virus-cell interactions and have significant implications for evaluating candidate HIV vaccines.


Assuntos
Moléculas de Adesão Celular/imunologia , Infecções por HIV/imunologia , Apoptose , Fusão Celular , Células Gigantes , Infecções por HIV/virologia , HIV-1 , Humanos , Testes de Neutralização , Vírion
16.
J Virol ; 72(11): 9384-91, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9765494

RESUMO

To study the antigenic conservation of epitopes of human immunodeficiency virus type 1 (HIV-1) isolates of different clades, the abilities of human anti-HIV-1 gp120 and gp41 monoclonal antibodies (MAbs) to bind to intact HIV-1 virions were determined by a newly developed virus-binding assay. Eighteen human anti-HIV MAbs, which were directed at the V2, V3 loop, CD4-binding domain (CD4bd), C5, or gp41 regions, were used. Nine HIV-1 isolates from clades A, B, D, F, G, and H were used. Microtiter wells were coated with the MAbs, after which virus was added. Bound virus was detected after lysis by testing for p24 antigen with a noncommercial p24 enzyme-linked immunosorbent assay. The anti-V3 MAbs strongly bound the four clade B viruses and viruses from the non-B clades, although binding was weaker and more sporadic with the latter. The degrees of binding by the anti-V3 MAbs to CXCR4- and CCR5-tropic viruses were similar, suggesting that the V3 loops of these two categories of viruses are similarly exposed. The anti-C5 MAbs bound isolates of clades A, B, and D. Only weak and sporadic binding of all the viruses tested with anti-CD4bd, anti-V2, and anti-gp41 MAbs was detected. These results suggest that V3 and C5 structures are shared and well exposed on intact virions of different clades compared to the CD4bd, V2, and gp41 regions.


Assuntos
Mapeamento de Epitopos , Antígenos HIV , HIV-1/imunologia , Anticorpos Monoclonais , Sequência Conservada , Ensaio de Imunoadsorção Enzimática , Anticorpos Anti-HIV , Antígenos HIV/genética , Proteína gp120 do Envelope de HIV/imunologia , Proteína gp41 do Envelope de HIV/imunologia , HIV-1/classificação , HIV-1/genética , Humanos , Técnicas In Vitro , Fragmentos de Peptídeos/imunologia
17.
J Virol ; 71(9): 6296-304, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9261346

RESUMO

Several members of the chemokine receptor family have recently been identified as coreceptors, with CD4, for entry of human immunodeficiency virus type 1 (HIV-1) into target cells. In this report, we show that the envelope glycoproteins of several strains of HIV-2 and simian immunodeficiency virus (SIV) employ the same chemokine receptors for infection. Envelope glycoproteins from HIV-2 use CCR5 or CXCR4, while those from several strains of SIV use CCR5. Our data indicate also that some viral envelopes can use more than one coreceptor for entry and suggest that some of these coreceptors remain to be identified. To further understand how different envelope molecules use CCR5 as an entry cofactor, we show that soluble purified envelope glycoproteins (SU component) from CCR5-tropic HIV-1, HIV-2, and SIV can compete for binding of iodinated chemokine to CCR5. The competition is dependent on binding of the SU glycoprotein to cell surface CD4 and implies a direct interaction between envelope glycoproteins and CCR5. This interaction is specific since it is not observed with SU glycoprotein from a CXCR4-tropic virus or with a chemokine receptor that is not competent for viral entry (CCR1). For HIV-1, the interaction can be inhibited by antibodies specific for the V3 loop of SU. Soluble CD4 was found to potentiate binding of the HIV-2 ST and SIVmac239 envelope glycoproteins to CCR5, suggesting that a CD4-induced conformational change in SU is required for subsequent binding to CCR5. These data suggest a common fundamental mechanism by which structurally diverse HIV-1, HIV-2, and SIV envelope glycoproteins interact with CD4 and CCR5 to mediate viral entry.


Assuntos
Antígenos CD4/metabolismo , Produtos do Gene env/metabolismo , Proteína gp120 do Envelope de HIV/metabolismo , HIV-1/metabolismo , HIV-2/metabolismo , Receptores de Citocinas/metabolismo , Receptores de HIV/metabolismo , Vírus da Imunodeficiência Símia/metabolismo , Células 3T3 , Animais , Anticorpos/imunologia , Linhagem Celular Transformada , Quimiocina CCL4 , Drosophila melanogaster , Produtos do Gene env/genética , Proteína gp120 do Envelope de HIV/genética , Proteína gp120 do Envelope de HIV/imunologia , Humanos , Proteínas Inflamatórias de Macrófagos/metabolismo , Camundongos , Fragmentos de Peptídeos/imunologia , Receptores CCR5 , Receptores de Citocinas/genética , Receptores de HIV/genética , Células Tumorais Cultivadas
18.
J Virol ; 71(5): 3444-50, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9094615

RESUMO

In addition to gp41 and gp120, an array of cell adhesion molecules is present on the envelope of human immunodeficiency virus type 1 (HIV-1). To examine the role of the host cell in the acquisition of these molecules by virions, both laboratory-adapted and primary isolates were sequentially passaged into different host cells. Viruses obtained from the various host cells were examined for the presence of 10 different cell-derived molecules by a virus binding enzyme-linked immunosorbent assay. Virus progeny raised in peripheral blood mononuclear cells expressed most of the adhesion molecules tested, with the level of LFA-1 being the highest. When viruses were passaged into CEM-SS or SupT1 cells, the expression of most of the adhesion molecules on the virus envelope was lost. In contrast, when viruses were passaged into MT2 cells, the virus progeny bore high levels of LFA-3, ICAM-1, and major histocompatibility complex classes I and II. These studies demonstrate for the first time the host cell dependence of the adhesion molecule profile present on the envelope of primary isolates of HIV-1. The presence of several adhesion molecules that have not previously been identified as components of the envelope of either laboratory or primary isolates is also described. In addition, we show that the adhesion molecule profile of the virions is acquired, or lost, within one passage and is maintained with subsequent passages in the same cell type.


Assuntos
Moléculas de Adesão Celular/análise , HIV-1/química , Vírion/química , Linhagem Celular , Membrana Celular/química , Antígenos HLA-DR/análise , Humanos
19.
J Immunol ; 149(6): 1889-95, 1992 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-1355502

RESUMO

Previous studies have demonstrated that murine CD4 Th1 cells lack perforin and use a pathway distinctive from CD8 CTL to express cytotoxicity. Whether the cytotoxic process of Th1 cells can be separated into identifiable stages and how these differences affect this process were determined in this study. We have resolved the cytotoxic process of Th1 clones into three stages identical with those of CD8 CTL, namely, conjugate formation/activation, lethal hit, and effector-independent programming for target DNA fragmentation. By comparing the cytotoxic processes between Th1 clones on Ag-pulsed targets and (PMA+A23187)-activated Th1 clones on unpulsed targets, we have also demonstrated that 1) the requirement of CD4 Th1 cells for de novo synthesis of cytotoxic machinery was partly responsible for the lag time in the induction of target DNA fragmentation by Th1 clones; 2) lethal hit was delivered rapidly; 3) lethal hit under forced contact by centrifugation did not need extracellular Ca2+ and Mg2+; 4) without centrifugation, lethal hit required extracellular Mg2+, but not Ca2+; 5) the average functional half life of the cytotoxic machinery was 54 +/- 24 (n = 4) min. The data demonstrate that the cytotoxic process of Th1 clones uses an activation-dependent cytotoxic machinery to deliver a short-lived, short-ranged, and quick-acting lethal hit to target, which induces a program in target for DNA fragmentation.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Citotoxicidade Imunológica , Subpopulações de Linfócitos T/imunologia , Linfócitos T Citotóxicos/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Animais , Calcimicina/farmacologia , Cátions Bivalentes , Cicloeximida/farmacologia , Citotoxicidade Imunológica/efeitos dos fármacos , Dano ao DNA , Dactinomicina/farmacologia , Camundongos , Acetato de Tetradecanoilforbol/farmacologia , Fatores de Tempo
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