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1.
Clin Immunol ; 210: 108307, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31760095

RESUMO

An increasing healthcare challenge in the management of haematological malignancy (HM) is secondary immunodeficiency. From January 2019, the EMA included the evaluation of specific antibody (Ab) responses to better select patients for immunoglobulin replacement therapy (IgRT). We evaluated Ab responses to pneumococcal and Salmonella typhi pure polysaccharide immunization in a cohort of 42 HM patients and 24 healthy-controls. Pre-post specific Ab concentrations were measured by ELISA at 4 weeks. Globally, significantly lower Typhim Vi (TV) seroprevalence (9%) compared to 23-valent pneumococcal polysaccharide vaccine (PPV) (76%) (p <0.001) was observed. TV non responders (88%) were higher than PPV non responders (62%) (p <0.0001) and correlated better to infectious history. By ROC analysis, pre-post 5-fold TV increase was the best cut-off to discriminate HM with recurrent infections and controls (sensitivity 91%, specificity 100%). Despite the small sample cohort, our results suggest that specific anti-S typhi Ab response is a useful complementary assay in the diagnosis and management decision of SID to HM.


Assuntos
Neoplasias Hematológicas/diagnóstico , Síndromes de Imunodeficiência/diagnóstico , Polissacarídeos Bacterianos/imunologia , Salmonella typhi/fisiologia , Febre Tifoide/imunologia , Vacinas Tíficas-Paratíficas/imunologia , Adulto , Idoso , Anticorpos Antibacterianos/sangue , Formação de Anticorpos , Estudos de Coortes , Feminino , Neoplasias Hematológicas/epidemiologia , Neoplasias Hematológicas/imunologia , Humanos , Síndromes de Imunodeficiência/epidemiologia , Síndromes de Imunodeficiência/imunologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Estudos Soroepidemiológicos , Espanha/epidemiologia
2.
MethodsX ; 7: 100936, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32551240

RESUMO

Assessment of specific antibody (Ab) production to polysaccharide antigens is clinically relevant, identifying patients at risk for infection by encapsulated bacteria and thus enabling a more rigorous selection of patients that can benefit of immunoglobulin replacement therapy. Classically, the gold-standard test is the measurement of antibody production to pure polysaccharide pneumococcal (PPV) immunization. Several factors, including introduction of conjugate vaccination schedule, serotyping analysis, high baseline Ab levels, have hindered the evaluation of polysaccharide antigens. This is even more difficult in secondary immunodeficiencies (SID), where patients can show secondary responses despite lack of primary antibody responses and present with recurrent or severe infections. Assessment of specific Ab production to pure Salmonella typhi Vi polysaccharide (TV) immunization has been proposed as a complementary test to PPV, given its low seroprevalence. To set the optimal cut-off value for PPV and TV response in SID, we tested different biostatistical methodologies, including ROC analysis, Youden index, Union index and Closest-topleft in a cohort of 42 SID patients and 24 healthy controls. The statistically chosen cut-offs value pre-post TV Ab ratio was ≥5, (sensitivity of 90%, specificity of 100%) and a postvaccination TV concentration of 28.5 U/mL (sensitivity of 90%, specificity of 95%), showing relevant clinical correlate.

3.
J Chromatogr A ; 922(1-2): 359-63, 2001 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-11486883

RESUMO

We describe a reversed-phase HPLC method that uses gradient elution and diode array detection to determine four biologically active phenolic constituents of red wines: gallic acid, trans-resveratrol, quercetin and rutin. The method permits direct injection without sample pre-treatment. ODS Hypersil served as the stationary phase; the gradient was formed by acetic acid, methanol, and water. Each analysis required an equilibration period of 10 min and a run time of 50 min for completion. Previously, total phenols were analysed according to the Folin-Ciocalteu method, using gallic acid as the standard, and the results are given as gallic acid equivalent.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Fenóis/análise , Vinho/análise , Calibragem , Espectrofotometria Ultravioleta
4.
Anat Embryol (Berl) ; 199(1): 29-34, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9924932

RESUMO

Pial microvessels have several important blood-brain barrier (BBB) characteristics in common with cerebral microvessels, despite lacking their astrocytic ensheathment. We have therefore determined whether they have the same distribution of two enzymes, gamma-glutamyl transpeptidase (GGTP) and alkaline phosphatase, both of which are known to be astrocyte-dependent. GGTP was absent from all rat pial microvessels but strongly present in brain cortical capillaries. Alkaline phosphatase was heterogeneously expressed in pial microvessels, including capillaries, but strongly positive in brain cortical capillaries. Diffusible, inductive factors produced by astrocytes could account for these differences in enzyme distribution between the two vessel types. Furthermore, differences in expression between the two markers may reflect their differing sensitivities to the astrocytic factors. Caution is urged in the common usage of the pial microvessel as a model system in BBB studies.


Assuntos
Fosfatase Alcalina/biossíntese , Capilares/enzimologia , Córtex Cerebral/irrigação sanguínea , Pia-Máter/irrigação sanguínea , gama-Glutamiltransferase/biossíntese , Animais , Arteríolas/enzimologia , Córtex Cerebral/enzimologia , Endotélio Vascular/enzimologia , Endotélio Vascular/ultraestrutura , Histocitoquímica , Microscopia Eletrônica , Pericitos/enzimologia , Pericitos/ultraestrutura , Pia-Máter/enzimologia , Ratos , Ratos Sprague-Dawley , Vênulas/enzimologia
5.
Anat Embryol (Berl) ; 199(6): 509-17, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10350131

RESUMO

A number of major properties of endothelial cells (EC) at the blood-brain barrier (BBB) have been shown to be astrocyte-dependent. Whether analogous properties at the blood-nerve barrier (BNB) are induced and maintained by Schwann cells has not been investigated. As a preliminary investigation we have undertaken a comparative study of six EC membrane markers at the BBB and BNB and perineurium. Employing immunoblotting and immunocytochemistry the relative distribution between rat brain cortex and sciatic nerve was determined for the glucose transporter (GLUT-1), the transferin receptor (OX-26), the endothelial barrier antigen (EBA) and the OX-47 antigen. Using enzyme cytochemistry the same comparison was made for gamma-glutamyl transpeptidase (GGTP) and alkaline phosphatase. By immunocytochemistry GLUT-1 was uniformly strongly represented in brain EC, nerve EC and perineurium. OX-26 was strongly positive in brain EC but present only in trace quantities in nerve EC and perineurium. EBA similarly showed strong positivity in brain EC and trace amounts in nerve EC but was absent from perineurium. OX-47 was present moderately in brain EC and perineurium but absent from nerve EC. Quantitative immunoblotting of brain and sciatic nerve homogenates showed statistically significant differences in the level of expression of EBA and OX-26 between the two tissues. Enzyme cytochemistry showed that GGTP was strongly positive in brain EC but absent from nerve EC and perineurium. Alkaline phosphatase stained strongly in brain and nerve EC and was absent from perineurium. In summary the six membrane markers were heterogeneously represented in nerve compared with brain. This pattern of distribution in the nerve cannot simply be accounted for by the absence of astrocytes and their inductive influences. Any inductive influences of Schwann cells require investigation.


Assuntos
Antígenos CD , Antígenos de Neoplasias , Antígenos de Superfície , Proteínas Aviárias , Biomarcadores/análise , Proteínas Sanguíneas , Barreira Hematoencefálica , Córtex Cerebral/irrigação sanguínea , Endotélio Vascular/metabolismo , Nervo Isquiático/irrigação sanguínea , Fosfatase Alcalina/metabolismo , Animais , Basigina , Western Blotting , Membrana Celular/metabolismo , Endotélio Vascular/citologia , Transportador de Glucose Tipo 1 , Técnicas Imunoenzimáticas , Glicoproteínas de Membrana/metabolismo , Microcirculação , Proteínas de Transporte de Monossacarídeos/metabolismo , Mucina-1/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores da Transferrina/metabolismo , gama-Glutamiltransferase/metabolismo
6.
J Pathol ; 192(3): 379-84, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11054722

RESUMO

The hypothesis for this study was that increased local expression of vascular angiotensin-converting enzyme (ACE) may contribute to the arterial remodelling which accompanies pulmonary hypertension, since angiotensin II (ANG II) is an important mediator of pulmonary vascular cell growth. The expression of ACE was studied by immunohistochemistry in paraffin-embedded lung sections from adults undergoing heart-lung transplantation for severe primary (n=6) and secondary (n=7) pulmonary arterial hypertension (PH), compared with age-matched controls (n=11). An antigen retrieval technique was used prior to incubating sections with the anti-ACE monoclonal antibody, CG2, or the endothelial marker, monoclonal anti-CD31. In control lungs, the highest level of ACE immunostaining was seen in the alveolar capillary endothelium, with less intense staining in small intra-acinar pulmonary arteries and relatively little staining in larger preacinar arteries. ACE immunostaining was virtually absent in lymphatics and veins. In both primary and secondary PH, there was an increase in ACE immunostaining in the endothelium of intra-acinar peripheral pulmonary arteries compared with control lungs, extending to the level of alveolar ducts, as confirmed by semi-quantitative analysis. The increase in endothelial ACE expression in the intra-acinar arteries of patients with primary and secondary PH is consistent with the hypothesis that locally increased production of ANG II may contribute to the process of pulmonary vascular remodelling.


Assuntos
Hipertensão Pulmonar/enzimologia , Peptidil Dipeptidase A/fisiologia , Adulto , Anticorpos Monoclonais , Estudos de Casos e Controles , Humanos , Hipertensão Pulmonar/patologia , Pulmão/irrigação sanguínea , Pulmão/enzimologia , Pessoa de Meia-Idade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/imunologia , Artéria Pulmonar/enzimologia , Artéria Pulmonar/patologia
7.
J Neurocytol ; 30(1): 35-44, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11577244

RESUMO

Evidence from a variety of sources suggests that pericytes have contractile properties and may therefore function in the regulation of capillary blood flow. However, it has been suggested that contractility is not a ubiquitous function of pericytes, and that pericytes surrounding true capillaries apparently lack the machinery for contraction. The present study used a variety of techniques to investigate the expression of contractile proteins in the pericytes of the CNS. The results of immunocytochemistry on cryosections of brain and retina, retinal whole-mounts and immunoblotting of isolated brain capillaries indicate strong expression of the smooth muscle isoform of actin (alpha-SM actin) in a significant number of mid-capillary pericytes. Immunogold labelling at the ultrastructural level showed that alpha-SM actin expression in capillaries was exclusive to pericytes, and endothelial cells were negative. Compared to alpha-SM actin, non-muscle myosin was present in lower concentrations. By contrast, smooth muscle myosin isoforms, were absent. Pericytes were strongly positive for the intermediate filament protein vimentin, but lacked desmin which was consistently found in vascular smooth muscle cells. These results add support for a contractile role in pericytes of the CNS microvasculature, similar to that of vascular smooth muscle cells.


Assuntos
Barreira Hematoencefálica/fisiologia , Proteínas Contráteis/análise , Pericitos/química , Actinas/análise , Animais , Proteínas de Ligação ao Cálcio/análise , Citoesqueleto , Desmina/análise , Técnicas Imunoenzimáticas , Masculino , Microcirculação , Proteínas dos Microfilamentos , Microscopia Imunoeletrônica , Pericitos/ultraestrutura , Molécula-1 de Adesão Celular Endotelial a Plaquetas/análise , Ratos , Ratos Sprague-Dawley , Vasos Retinianos/química , Vasos Retinianos/citologia , Miosinas de Músculo Liso/análise , Vimentina/análise , Calponinas
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