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1.
J Eur Acad Dermatol Venereol ; 31(3): 523-529, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27557471

RESUMO

BACKGROUND: Dysregulation of apoptosis has an important role in the induction of autoimmunity. OBJECTIVE: To evaluate the influence of keratinocyte apoptosis and deoxyribonuclease I (DNase I) activity on the clinical and immunoserological parameters of cutaneous lupus erythematosus (CLE). METHODS: We studied 69 CLE patients (39 with discoid LE (DLE), 12 with subacute CLE (SCLE), 12 with acute and 6 with intermittent CLE). Thirty of sixty-nine patients fulfilled criteria for systemic LE (SLE). Apoptotic index (AI) was evaluated immunohistochemically in lesional and non-lesional, photoprotected skin. Serum DNase I activity, antichromatin and anti-ENA antibodies were measured by ELISA. Disease activity was determined by SLEDAI-2K, SLICC/ACR, CLASI and RCLASI. RESULTS: AI in lesions was higher than in non-lesional skin (P < 0.001). There was no difference in AI between CLE and SLE patients. Patients with SCLE had higher lesional AI than patients with DLE (P < 0.05). We found a positive correlation between the lesional AI with CLASI A (P < 0.05) and RCLASI D (P < 0.05). CLE and SLE patients had significantly lower DNase I activity than healthy controls (P < 0.001). Patients with normal DNase I activity and low AI had significantly lower CLASI A than patients with decreased DNase I activity and/or elevated AI (P < 0.05). CONCLUSIONS: Increased keratinocyte apoptosis characterizes lesions of all CLE forms, especially of SCLE. AI correlates with CLE markers of acute and chronic inflammation. Normal level of apoptosis and DNase I activity simultaneously reduce the level of acute inflammation in CLE. Serum DNase I activity and AI might be important biomarkers in the evaluation of CLE patients.


Assuntos
Apoptose , Desoxirribonuclease I/sangue , Lúpus Eritematoso Cutâneo/enzimologia , Lúpus Eritematoso Cutâneo/fisiopatologia , Lúpus Eritematoso Sistêmico/enzimologia , Lúpus Eritematoso Sistêmico/fisiopatologia , Adolescente , Adulto , Idoso , Anticorpos Antinucleares/sangue , Antígenos Nucleares/sangue , Biomarcadores/sangue , Estudos Transversais , Feminino , Humanos , Queratinócitos/fisiologia , Lúpus Eritematoso Cutâneo/imunologia , Lúpus Eritematoso Sistêmico/imunologia , Masculino , Pessoa de Meia-Idade , Índice de Gravidade de Doença , Fenômenos Fisiológicos da Pele , Adulto Jovem
2.
Phys Rev Lett ; 117(17): 176602, 2016 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-27824472

RESUMO

Recent experiments reporting an unexpectedly large spin Hall effect (SHE) in graphene decorated with adatoms have raised a fierce controversy. We apply numerically exact Kubo and Landauer-Büttiker formulas to realistic models of gold-decorated disordered graphene (including adatom clustering) to obtain the spin Hall conductivity and spin Hall angle, as well as the nonlocal resistance as a quantity accessible to experiments. Large spin Hall angles of ∼0.1 are obtained at zero temperature, but their dependence on adatom clustering differs from the predictions of semiclassical transport theories. Furthermore, we find multiple background contributions to the nonlocal resistance, some of which are unrelated to the SHE or any other spin-dependent origin, as well as a strong suppression of the SHE at room temperature. This motivates us to design a multiterminal graphene geometry which suppresses these background contributions and could, therefore, quantify the upper limit for spin-current generation in two-dimensional materials.

3.
J Appl Microbiol ; 119(2): 389-99, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26033505

RESUMO

AIMS: In the present work, the Libyan wild-growing Thymus capitatus essential oil (EO) was evaluated for its biological properties. METHODS AND RESULTS: Carvacrol (68.19%) and thymol (12.29%) were found to be the main compounds of the oil. Antioxidant properties, determined by 2,2-diphenylpicrylhydrazyl (DPPH) assay, revealed that IC50 values were 119, 403 and 105 µg ml(-1) for oil, thymol and carvacrol respectively. Microdilution method showed strong antibacterial and especially antifungal potential. Tetrazolium (MTT) colorimetric assay indicated moderate cytotoxicity towards human cell lines MRC-5, HCT 116 and HT-29 (IC50 = 30-150 µg ml(-1)). In adhesion-inhibition assay oil and main compounds reduced adhesion of Escherichia coli and Listeria monocytogenes on colon cells HT-29 (51 and 39% of inhibition against L. monocytogenes and E. coli respectively). CONCLUSIONS: Essential oil of Th. capitatus showed moderate cytotoxic activity, together with excellent antimicrobial effect, in particular against fungi, and significant potential to reduce pathogen colonization in colon. SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first report that EO of Th. capitatus could protect against colonization of pathogens to colon epithelium. Thymus capitatus from Libya should be recognized as possible new source of natural antioxidants, antimicrobials as well as possible source of new chemotherapeutics.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Colo/microbiologia , Óleos Voláteis/farmacologia , Extratos Vegetais/farmacologia , Thymus (Planta)/química , Anti-Infecciosos/química , Antioxidantes/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/fisiologia , Fungos/efeitos dos fármacos , Fungos/crescimento & desenvolvimento , Humanos , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/crescimento & desenvolvimento , Listeria monocytogenes/fisiologia , Óleos Voláteis/química , Extratos Vegetais/química
4.
Int Endod J ; 48(10): 966-75, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25288256

RESUMO

AIM: To evaluate in vitro cytotoxicity and in vivo inflammatory response to new nanostructural materials based on active calcium silicate systems (CS) and hydroxyapatite (HA-CS). METHODOLOGY: Cytotoxicity of eluates of new nanostructural noncommercial materials CS and HA-CS, and MTA (White MTA, Angelus(®) Soluções Odontológicas, Londrina, Brazil) as a control, were tested using the MTT assay on MRC-5 cells. Eluates of set materials were tested in 100% and 50% concentrations, 24 h, 7 days and 21 days post-elution. The pH values were determined for undiluted eluates of set materials. Polyethylene tubes containing the test materials (CS, HA-CS, MTA) were implanted in subcutaneous tissue of Wistar rats. Histopathological examinations were conducted at 7, 15, 30 and 60 days after the implantation. Data were statistically analyzed using three-way and one-way anova Tukey's post hoc test as well as Kruskall-Wallis test with Dunn's post hoc test at α = 0.05. RESULTS: All materials significantly reduced cell viability; especially when undiluted eluates were used (P < 0.001). After 24 h elution, cell viability was 10 ± 1.8%, 49.5 ± 4.2% and 61 ± 7.4%, for MTA, and HA-CS, respectively. However, CS and HA-CS were significantly less toxic than the control material MTA (P < 0.05). Cytotoxicity could be at least partially attributed to pH kinetics over time. Dilution of eluates of all tested materials resulted in better cell survival. Histopathological examination indicated similar inflammatory reaction, vascular congestion and connective tissue integrity associated with CS, HA-CS and MTA at each observation period (P > 0.05). The only significant difference was found for capsule thickness, that is thicker capsule was associated with HA-CS compared to MTA at 60 days (P = 0.0039). HA-CS induced moderately thick capsules (median score 3, score range 2-3), whereas MTA resulted in thin capsule formation (median score 2, score range 1-3). CONCLUSIONS: Evaluation of cytotoxicity and inflammatory response indicated better biocompatibility of CS and HA-CS, in comparison with MTA (White MTA, Angelus(®) Soluções Odontológicas, Londrina, Brazil).


Assuntos
Compostos de Alumínio/toxicidade , Materiais Biocompatíveis/toxicidade , Compostos de Cálcio/toxicidade , Durapatita/toxicidade , Fibroblastos/efeitos dos fármacos , Nanoestruturas/toxicidade , Óxidos/toxicidade , Materiais Restauradores do Canal Radicular/toxicidade , Silicatos/toxicidade , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Tecido Conjuntivo/efeitos dos fármacos , Combinação de Medicamentos , Humanos , Concentração de Íons de Hidrogênio , Teste de Materiais , Ratos , Ratos Wistar , Tela Subcutânea/efeitos dos fármacos
5.
Int Endod J ; 46(6): 506-16, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23173688

RESUMO

AIM: To characterize and investigate the genotoxic effect of a new endodontic cement based on dicalcium- and tricalcium-silicate (CS) with hydroxyapatite (HA) on human lymphocytes. METHODOLOGY: Hydrothermal treatment was applied for synthesis of CS and HA. The final mixture HA-CS, with potential to be used in endodontic practice, is composed of CS (34%) and HA (66%). Human lymphocytes were incubated with HA, HA-CS and CS for 1 h, at 37 °C and 5% CO2. Cell viability was determined using the trypan blue exclusion assay. To evaluate the level of DNA damage comet assay (single cell gel electrophoresis) was performed. For the statistical analysis anova and Duncan's Post Hoc Test were used. RESULTS: The SEM analysis indicated that CS consisted mostly of agglomerates of several micrometers in size, built up from smaller particles, with dimensions between 117 and 477 nm. This is promising because dimensions of agglomerates are not comparable with channels inside the cell membranes, whereas their nano-elements provide evident activity, important for faster setting of these mixtures compared to MTA. Values of DNA damage obtained in the comet assay indicated low genotoxic risk of the new endodontic materials. CONCLUSIONS: The significantly improved setting characteristics and low genotoxic risk of the new material support further research.


Assuntos
Materiais Biocompatíveis/toxicidade , Compostos de Cálcio/toxicidade , Durapatita/toxicidade , Linfócitos/efeitos dos fármacos , Mutagênicos/toxicidade , Nanopartículas/toxicidade , Materiais Restauradores do Canal Radicular/toxicidade , Silicatos/toxicidade , Compostos de Cálcio/síntese química , Dióxido de Carbono/química , Técnicas de Cultura de Células , Sobrevivência Celular/efeitos dos fármacos , Ensaio Cometa , Dano ao DNA/genética , Durapatita/síntese química , Humanos , Masculino , Teste de Materiais , Microscopia Eletrônica de Varredura , Testes de Mutagenicidade , Materiais Restauradores do Canal Radicular/síntese química , Silicatos/síntese química , Espectrometria por Raios X , Temperatura , Fatores de Tempo , Difração de Raios X , Adulto Jovem
6.
Lupus ; 21(1): 100-2, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21976399

RESUMO

There is an increase in the number of patients with systemic lupus erythematosus (SLE) reported as developing progressive multifocal leukoencephalopathy (PML) while on intensive immunosuppressive therapy. A 39-year-old HIV-negative woman with a 10-year history of SLE presented with progressive left-side weakness while on maintenance therapy with oral prednisone and mycophenolate mofetil (MMF). On several occasions low CD4+ T-lymphocyte counts were found (68/µL). Brain magnetic resonance imaging (MRI) revealed a large lesion in the right subcortical fronto-parietal region and a smaller one in the left frontal subcortex, corresponding to the PML. In cerebrospinal fluid, polymerase chain reaction (PCR) for JC virus (JCV) was negative, but anti-JCV antibodies were highly positive. Diagnosis of probable PML was made and MMF was withdrawn. The patient's condition improved with marked reduction of left-side weakness and an increase in CD4(+) T-lymphocyte count (141/µL). Follow-up MRI showed regression of lesions and over the next 6 months the patient remained stable. In spite of the grave prognosis associated with PML, SLE patients can have an excellent outcome if immunosuppressants are discontinued as soon as the correct diagnosis is made. SLE patients with associated low CD4(+) T-lymphocyte counts should be monitored for the development of PML during immunosuppressive therapy in particular.


Assuntos
Contagem de Linfócito CD4 , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Imunossupressores/efeitos adversos , Leucoencefalopatia Multifocal Progressiva/induzido quimicamente , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Ácido Micofenólico/análogos & derivados , Adulto , Feminino , Humanos , Vírus JC/fisiologia , Leucoencefalopatia Multifocal Progressiva/patologia , Leucoencefalopatia Multifocal Progressiva/virologia , Lúpus Eritematoso Sistêmico/complicações , Imageamento por Ressonância Magnética , Ácido Micofenólico/efeitos adversos , Ativação Viral
7.
Eur J Gynaecol Oncol ; 33(5): 512-6, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23185799

RESUMO

INTRODUCTION: It is now believed that the majority of cervical cancer is preceded by long-term infection with high-risk types of the human papilloma virus (HPV). The presence of HPV high-risk types (HR-HPV) in the cells of intraepithelial change multiplies the possibility of its progressive development to high-grade cervical precancer and invasive disease. AIM: This study examined the correlation of HPV infection with cytology, colposcopy, and histopathological examination of the bioptic tissue in low- and high-grade cervical lesions. MATERIALS AND METHODS: This research was conducted as a study section. Data collection was performed during a ten-year period, at the University Clinic of Gynecology and Obstetrics - Narodni Front in Belgrade (Serbia). The basic set included 1,927 patients. Colposcopy, cytology, histopathology, and HPV test verification was made in all patients. Statistical analysis was performed using the SPSS program, version 17.0. Contingency tables were used to assess the degree of correlation of variables and chi-square test was used to determine the level of statistical significance in this study. A p value < 0.05 was considered statistically significant. RESULTS: Among 1,927 women studied, 635 (32.95 %) had abnormal cytological findings and among these, 272 (42.83%) were HR-HPV positive. There was a statistical difference between colposcopic and cytological findings in patients with HR-HPV (x2 = 35.33, p = 0.000). There was also a statistically significant difference between histophatological and colposcopical findings in patients with HR-HPV (x2 = 10,171, p = 0.001). Only HR-HPV types 16 and 18 showed a statistical significance compared to histopathological findings, unlike other HR-HPV. An important finding was that the authors found an abnormal colposcopy in 93.30% patients with low-grade intraepithelial neoplasia and 68.05% patients with low-grade squamous intraepithelial lesion (LSIL) had normal cytology and was 70.15 % HR-HPV negative. CONCLUSION: The findings imply that among high-grade intraepithelial neoplasias, the authors found a high presence of HPV type 16 and 18, and a statistical significant presence of HPV 16 in low-grade intraepithelial neoplasia, unlike other HR-HPV types in low-grade intraepithelial findings. The authors found a significant statistical correlation with abnormal cytology and presence of HPV type 16 in both groups (LSIL and high-grade squamous intraepithelial lesion (HSIL). The authors also found an abnormal colposcopy in 93.30% of patients with low-grade intraepithelial neoplasia, while 68.05% of patients with LSIL had normal cytology and were HR-HPV negative in 70.15% of the cases.


Assuntos
Colposcopia/métodos , Infecções por Papillomavirus/patologia , Displasia do Colo do Útero/virologia , Neoplasias do Colo do Útero/virologia , Adolescente , Adulto , Idoso , Biópsia , Feminino , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias do Colo do Útero/patologia , Displasia do Colo do Útero/patologia
8.
Clin Exp Obstet Gynecol ; 39(4): 479-82, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23444748

RESUMO

PURPOSE OF INVESTIGATION: The objective of this study was to evaluate the electrolytic status of Na+, K+, Ca+, and Mg2+ in serum and red blood cells in idiopathic preterm and term deliveries. METHODS: The study included 105 pregnant women diagnosed with idiopathic premature delivery (study group) and 36 pregnant women with physiologically term delivery (controls). Samples of mother's blood were collected and analyzed for the level of electrolytes in the serum/plasma and red blood cells. RESULTS: Measured values of magnesium in red blood cells in the study group were far lower than physiological values, intracellular calcium levels were higher in the study group compared to levels measured in the controls. Sodium concentrations in cells were significantly lower in subjects with premature delivery. CONCLUSION: The magnesium intracellular level is the best representative value of magnesium in the body.


Assuntos
Eletrólitos/sangue , Parto/fisiologia , Nascimento Prematuro/sangue , Contração Uterina/fisiologia , Adulto , Eritrócitos/química , Feminino , Humanos , Hipercalciúria/fisiopatologia , Recém-Nascido , Magnésio/sangue , Nefrocalcinose/fisiopatologia , Gravidez , Erros Inatos do Transporte Tubular Renal/fisiopatologia , Sódio/sangue , Adulto Jovem
9.
Clin Exp Immunol ; 159(3): 327-37, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20015271

RESUMO

Wegener's granulomatosis (WG) is a life-threatening autoimmune vasculitis that affects lungs, kidneys and other organs. A hallmark of WG is the presence of classic anti-neutrophil cytoplasmic antibodies (c-ANCA) against self-proteinase 3 (PR3). Little is known about the role of these antibodies and PR3-specific immune responses in disease development. In this study, we demonstrate that PR3-specific autoimmune responses are pathogenic in non-obese diabetic (NOD) mice with an impaired regulatory arm of the immune response. Immunization of autoimmunity prone NOD mice with rmPR3 (recombinant mouse PR3) in complete Freund's adjuvant (CFA) resulted in high levels of c-ANCA, without detectable disease development. However, when splenocytes from these immunized mice were transferred into immunodeficient NOD-severe combined immunodeficiency (SCID) mice, the recipient mice developed vasculitis and severe segmental and necrotizing glomerulonephritis. No disease developed in NOD-SCID mice that received splenocytes from the CFA-alone-immunized donors (controls), indicating that disease development depends upon PR3-specific immune responses. In contrast to the pathology observed in NOD-SCID mice, no disease was observed when splenocytes from rmPR3-immunized C57BL/6 mice were transferred into immunodeficient C57BL/6-RAG-1(-/-) mice, suggesting that complex and probably multi-genetic factors play a role in the regulation of disease development.


Assuntos
Anticorpos Anticitoplasma de Neutrófilos/imunologia , Especificidade de Anticorpos/imunologia , Doenças Autoimunes/imunologia , Glomerulosclerose Segmentar e Focal/imunologia , Granulomatose com Poliangiite/imunologia , Mieloblastina/imunologia , Animais , Doenças Autoimunes/induzido quimicamente , Doenças Autoimunes/patologia , Glomerulosclerose Segmentar e Focal/induzido quimicamente , Glomerulosclerose Segmentar e Focal/patologia , Granulomatose com Poliangiite/induzido quimicamente , Granulomatose com Poliangiite/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos Knockout , Camundongos SCID , Especificidade da Espécie
10.
J Cell Biol ; 134(6): 1455-67, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8830774

RESUMO

We have generated a series of plectin deletion and mutagenized cDNA constructs to dissect the functional sequences that mediate plectin's interaction with intermediate filament (IF) networks, and scored their ability to coalign or disrupt intermediate filaments when ectopically expressed in rat kangaroo PtK2 cells. We show that a stretch of approximately 50 amino acid residues within plectin's carboxy-terminal repeat 5 domain serves as a unique binding site for both vimentin and cytokeratin IF networks of PtK2 cells. Part of the IF-binding domain was found to constitute a functional nuclear localization signal (NLS) motif, as demonstrated by nuclear import of cytoplasmic proteins linked to this sequence. Site directed mutagenesis revealed a specific cluster of four basic amino acid residues (arg4277-arg4280) residing within the NLS sequence motif to be essential for IF binding. When mutant proteins corresponding to those expressed in PtK2 cells were expressed in bacteria and purified proteins subjected to a sensitive quantitative overlay binding assay using Eu3+-labeled vimentin, the relative binding capacities of mutant proteins measured were fully consistent with the mutant's phenotypes observed in living cells. Using recombinant proteins we also show by negative staining and rotary shadowing electron microscopy that in vitro assembled vimentin intermediate filaments become packed into dense aggregates upon incubation with plectin repeat 5 domain, in contrast to repeat 4 domain or a mutated repeat 5 domain.


Assuntos
Aminoácidos/química , Núcleo Celular/metabolismo , Proteínas de Filamentos Intermediários/química , Vimentina/química , Sequência de Aminoácidos , Animais , Fenômenos Fisiológicos Bacterianos , Sequência de Bases , Sítios de Ligação/fisiologia , Transporte Biológico/fisiologia , Linhagem Celular/fisiologia , Citoplasma/química , Citoplasma/fisiologia , Citoesqueleto/química , Expressão Gênica/fisiologia , Proteínas de Filamentos Intermediários/metabolismo , Proteínas de Filamentos Intermediários/ultraestrutura , Queratinócitos/fisiologia , Queratinas/metabolismo , Macropodidae , Camundongos , Microscopia Eletrônica , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Plectina , Estrutura Terciária de Proteína , Proteínas Recombinantes/metabolismo , Vimentina/metabolismo , Vimentina/ultraestrutura
11.
J Clin Invest ; 105(9): 1289-98, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10792004

RESUMO

STAT4 and STAT6 are transcription factors that play crucial roles in responding to IL-12 and IL-4, respectively. STAT4 gene knockout (STAT4(-/-)) mice have markedly reduced Th1 responses and enhanced Th2 responses. STAT6(-/-) mice show the inverse phenotype. We compared the ability of bone marrow transplantation (BMT) with the inclusion of spleen cells from STAT6(-/-), STAT4(-/-), and wild-type (WT) mice to produce graft-versus-host disease (GVHD) in lethally irradiated MHC-mismatched recipients. Acute GVHD mortality was more rapid when induced by cells from STAT6(-/-) mice than when induced by STAT4(-/-) cells. However, cells from STAT4(-/-) and STAT6(-/-) donors both induced delayed GVHD mortality compared with WT controls, or compared with combined STAT4(-/-) and STAT6(-/-) cells, indicating a contribution of both Th1 cells and Th2 cells to acute GVHD. Recipients of STAT6(-/-) BMT showed evidence of acute GVHD with severe diarrhea and marked weight loss. Recipients of STAT4(-/-) BMT showed signs of GVHD with only initial transient weight loss and later development of severe skin GVHD. Histopathology showed that Th2 responses were required for the induction of both hepatic and severe skin GVHD. In contrast, both Th1 cells and Th2 cells were capable of causing intestinal pathology of GVHD. Our studies demonstrate an additive role for Th1 and Th2 cells in producing acute GVHD, and suggest a cytokine-directed approach to treating end-organ manifestations of GVHD.


Assuntos
Doença Enxerto-Hospedeiro/imunologia , Subpopulações de Linfócitos T/imunologia , Células Th1/imunologia , Células Th2/imunologia , Doença Aguda , Animais , Transplante de Medula Óssea , Proteínas de Ligação a DNA/genética , Doença Enxerto-Hospedeiro/mortalidade , Antígenos H-2 , Intestino Grosso/patologia , Fígado/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Especificidade de Órgãos , Quimera por Radiação , Fator de Transcrição STAT4 , Fator de Transcrição STAT6 , Pele/patologia , Baço/citologia , Baço/transplante , Síndrome , Transativadores/genética , Redução de Peso
12.
Curr Opin Immunol ; 9(5): 634-40, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9368771

RESUMO

Engraftment of allogeneic or xenogeneic pluripotent hematopoietic stem cells into nonmyeloablated but immunodepleted (preconditioned) recipients can produce a state of immunological tolerance to donor and host. Host and donor hematopoietic cells entering the thymus ensure deletion of both donor- and host-reactive thymocytes. Additional mechanisms are involved in tolerance induced in recipients that are not immunodepleted. Grafting of donor thymic tissue to thymectomized recipients is an alternative approach for inducing central T cell tolerance without the requirement for engraftment of donor hematopoietic stem cells. During the past year, advances have been made in understanding both the requirements for preconditioning and the mechanisms of tolerance induction in the above transplantation models.


Assuntos
Transplante de Medula Óssea , Quimeras de Transplante , Imunologia de Transplantes , Humanos
13.
Clin Exp Rheumatol ; 25(3): 361-6, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17631730

RESUMO

OBJECTIVE: The link between specific antibodies and atherogenesis in primary antiphospholipid syndrome (PAPS) is less strong than for thrombosis, although clearly the two processes are related and thrombosis is the main complication of atherosclerosis, a process known as atherothrombosis. The aim of this study was to investigate the influence of serum lipid levels and anti-oxidized LDL (oxLDL) antibodies on the clinical features of 42 patients with PAPS (mean age 40.45+/-13.37; 32 women and 10 men), and to compare them with 47 control subjects (mean age 39.68+/-13.93; 33 women and 14 men). METHODS: Total cholesterol, HDL and triglyceride concentrations were determined by enzymatic methods. LDL was calculated according to the Friedwald formula. Anticardiolipin, anti-oxidized LDL and anti-Beta2glycoprotein I antibodies were detected by ELISA. RESULTS: A significant association was found between arterial events and triglyceride, LDL and cholesterol concentrations, but multivariate analysis showed that cholesterol concentrations were the most important predictor of arterial events (p=0.012). Cerebrovascular insults were the most significantly associated with cholesterol concentrations (p=0.011). Myocardial infarctions were more frequently present in patients more than 40 years of age (p=0.032). No significant association of the investigated parameters with venous thromboses was found. Recurrent abortions were not associated with the presence or concentrations of the investigated parameters. Although patients had increased concentrations of anti-oxLDL antibodies, no significant association was found between the titres of anti-oxLDL antibodies and clinical features of APS. CONCLUSION: In patients with PAPS, lipid concentrations are a better predictor for arterial events than anti-oxLDL antibodies.


Assuntos
Anticorpos Anti-Idiotípicos/sangue , Síndrome Antifosfolipídica/sangue , Lipídeos/sangue , Lipoproteínas LDL/imunologia , Adulto , Idoso , Anticorpos Anticardiolipina/sangue , Síndrome Antifosfolipídica/imunologia , Aterosclerose/etiologia , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Fatores de Risco , Trombose/etiologia , beta 2-Glicoproteína I/imunologia
14.
Clin Nephrol ; 67(1): 58-60, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17269602

RESUMO

We report a case of a male teenager with severe heart and acute renal failure as the dominant clinical manifestations of renovascular hypertension (RVH) caused by atypical giant cell arteritis (GCA). Unrecognized RVH and treatment of the consequent heart failure by angiotensin-converting enzyme inhibitors (ACEI) probably contributed to progression of renovascular disease to bilateral renal artery occlusion. Recurrent "flash" pulmonary edemas could not be prevented until surgical revascularization of the only functioning right kidney was achieved by an aortorenal bypass. Prompt post-operative normalization of heart function and arterial hypertension occurred despite the histopathological finding of the resected renal artery compatible with GCA and 4-year duration of significant renovascular disease. At the last check-up, the patient was asymptomatic, with normal arterial pressure on the prescribed treatment: carvedilol, hydrochlorothiazide, prednisolone 20 mg daily and aspirin. Subsequent follow-up is necessary to observe the evolution of GCA as an exceptionally rare cause of RVH.


Assuntos
Injúria Renal Aguda/etiologia , Arterite de Células Gigantes/complicações , Insuficiência Cardíaca/etiologia , Hipertensão Renovascular/etiologia , Adolescente , Arterite de Células Gigantes/diagnóstico , Humanos , Masculino , Edema Pulmonar/etiologia
15.
Immunol Res ; 16(3): 217-28, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9379073

RESUMO

Durable transplantation tolerance can be reliably achieved by inducing engraftment of hematopoietic cells in recipients initially depleted of T-lymphocytes. Engraftment of donor pluripotent hematopoietic stem cells (PPHSC) produces mixed hematopoietic chimeras in which both host and donor cells coexist and are tolerant of each other. The major mechanism of tolerance in these chimeras is central, intrathymic clonal deletion, which is induced and maintained by immigration of both host and donor marrow-derived cells to the host thymus, ensuring the ongoing central deletion of donor- and host-reactive cells. In this article, approaches developed in our laboratory to induce stable mixed hematopoietic chimerism and specific central deletional allogeneic and xenogeneic tolerance without toxic or myeloablative host conditioning are reviewed.


Assuntos
Hematopoese/imunologia , Transplante de Células-Tronco Hematopoéticas , Quimeras de Transplante , Animais , Hematopoese/genética , Humanos , Tolerância Imunológica
16.
Transplantation ; 65(9): 1216-24, 1998 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-9603171

RESUMO

BACKGROUND: Mixed xenogeneic bone marrow chimerism and tolerance can be induced in mice conditioned with a nonmyeloablative regimen followed by injection of T cell-depleted rat bone marrow cells. We hypothesized that, despite a gradual decline in rat hematopoiesis observed in these chimeras, as long as rat class II+ antigen-presenting cells remain in their thymi, tolerance will persist as a result of deletion of donor-reactive thymocytes. METHODS: The level of chimerism and of mouse Vbeta5 and Vbeta11 T-cell deletion was followed over time. These results were correlated with the presence of rat class II+ cells in the thymus by immunohistochemistry and the presence of tolerance in long-term chimeras by in vivo and in vitro assays. RESULTS: (1) Proliferation and cytotoxicity assays, as well as skin graft survival, demonstrated the presence of specific tolerance to host and to donor rat, with normal reactivity to third-party rat and mouse stimulators, even as late as 85 weeks after bone marrow transplantation. (2) The absence of mature Vbeta5+ and Vbeta11+ host T cells in the thymus and periphery was always associated with the presence of rat class II+ cells in the thymus, and incomplete deletion of T cells expressing these Vbeta families was observed in thymi in which rat class II+ cells were not detectable. CONCLUSIONS: Donor-specific T-cell tolerance is maintained during the period when donor-type reconstitution declines, and is most likely mediated by intrathymic clonal deletion of T cells that recognize antigens expressed on class II+ rat cells.


Assuntos
Transplante de Medula Óssea , Medula Óssea/fisiologia , Quimera/genética , Deleção Clonal/fisiologia , Antígenos de Histocompatibilidade Classe II/análise , Tolerância Imunológica/genética , Timo/imunologia , Timo/fisiologia , Transplante Heterólogo , Animais , Quimera/fisiologia , Feminino , Camundongos , Camundongos Endogâmicos , Ratos , Ratos Endogâmicos , Receptores de Antígenos de Linfócitos T alfa-beta/metabolismo , Linfócitos T/metabolismo , Timo/citologia
17.
Brain Res ; 814(1-2): 13-25, 1998 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-9838024

RESUMO

The development of microglia and macrophages was studied in 14 human embryos and fetuses ranging in age from 4.5-13.5 gestational weeks (g.w.), using lectins, Ricinus communis agglutinin-1 [RCA-1], and Lycopersicon esculentum, tomato lectin (TL), which recognize macrophages and microglia, and antibodies for the macrophage antigen CD68. Lectin-positive (+) cells were observed at 4.5 g.w., the youngest age examined. They were detected in the leptomeninges around the neural tube, and only rarely were observed in the CNS parenchyma. At 5.5 g.w., lectin+ cells were present throughout the CNS parenchyma, and a portion of these cells could also be labeled with antibody to CD68. In subsequent weeks, both types of cells, lectin+ and CD68+/lectin+ cells co-existed and progressively developed typical microglial morphology. In addition, in double label experiments, an antibody that labels CD14 antigen present on monocytes, hematogenous precursors of tissue macrophages, did not label either lectin+ or CD68+/lectin+ cells in CNS parenchyma. Additional immunocytochemical studies with appropriate markers excluded the possibility that any of the cells described here were either astrocytes, oligodendrocytes, endothelial cells or neurons. Our finding that one class of cells can be labeled early only with lectins, while another can be labeled with both lectins and CD68 macrophage antibody, may reflect a different origin of microglia in the early embryonic CNS compared to the fetal stages. This subdivision appears to be maintained in the adult brains as well.


Assuntos
Encéfalo/metabolismo , Lectinas/análise , Macrófagos/química , Microglia/química , Encéfalo/citologia , Encéfalo/embriologia , Desenvolvimento Embrionário e Fetal/fisiologia , Idade Gestacional , Histocitoquímica , Humanos , Imuno-Histoquímica
18.
Neurosci Lett ; 131(1): 121-4, 1991 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-1686476

RESUMO

Catecholaminergic systems were visualized in the CNS of human embryos from stage 15-16 (5 gestational week, g.w.) to 18 (6 g.w.) using tyrosine hydroxylase (TH) and dopamine-beta-hydroxylase (DBH) as immunocytochemical markers. At 5 g.w., several TH-like immunoreactive (TH-IR) cell groups were identified in the medulla oblongata, pons, mesencephalon and the anlage of the hypothalamic area. DBH immunoreactivity was restricted to the locus coeruleus and to rare neurons in the medulla oblongata. At 6 g.w., the density of TH-IR neurons was strikingly increased in these different areas--especially in the prospective substantia nigra and ventral tegmental area--and two main bundles of catecholaminergic axons extended from the medulla oblongata until the basal forebrain and from the mesencephalic tegmentum to the anlage of the striatum. These pathways were mainly TH-IR but DBH-IR was also observed in the former. No TH-IR fibers reached the telencephalon at 6 g.w.


Assuntos
Encéfalo/embriologia , Dopamina beta-Hidroxilase/análise , Neurônios/enzimologia , Tirosina 3-Mono-Oxigenase/análise , Encéfalo/citologia , Encéfalo/enzimologia , Catecolaminas/fisiologia , Embrião de Mamíferos , Desenvolvimento Embrionário e Fetal , Humanos , Imuno-Histoquímica , Neurônios/citologia
19.
Clin Chim Acta ; 101(1): 151-4, 1980 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-7357735

RESUMO

Using sulfonated polysaccharides to precipitate beta-lipoprotein in serum, we obtained high values in certain cases with normal serum lipids. Therefore, we examined whether there are proteins in such sera which precipitate under conditions optimal for beta-lipoprotein insolubilization. The results show that certain IgG paraproteins are precipitable by sulfonated polysaccharides giving erroneously high values for beta-lipoprotein.


Assuntos
Imunoglobulina G/análise , Lipoproteínas LDL/sangue , Paraproteínas/análise , Precipitação Química , Eletroforese em Gel de Ágar , Reações Falso-Positivas , Humanos , Imunoeletroforese
20.
Clin Exp Rheumatol ; 20(4): 499-504, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12175105

RESUMO

OBJECTIVE: Epidermal in vivo nuclear staining is occasionally noted in the lupus band test (LBT) in patients with connective tissue diseases (CTD). The exact clinical significance of this finding remains unelucidated, especially in association with a positive LBT We have reviewed the clinical and serological characteristics of patients with in vivo-bound antinuclear antibodies (ANA) in keratinocytes. METHODS: Between 1990-1999 speckled IgG staining in keratinocyte nuclei was observed in 31 LBT specimens. We had detailed clinical and laboratory data for 22/31 patients. The present study comprises 22 patients with in vivo-bound ANA (8 cases with mixed CTD (MCTD), 10 with systemic lupus erythematosus (SLE), 2 with Sjögren's syndrome (SS), one with undefined CTD and one clinically healthy mother of a child with neonatal lupus erythematosus), and 22 consecutive CTD patients (2 MCTD, 15 SLE, 5 SS) without in vivo-bound ANA. Antinuclear, anti-dsDNA and anti-extractable nuclear antigens (ENA) antibodies were determined using indirect immunofluorescence and ELISA methods. RESULTS: A significant difference (p < 0.01) in anti-RNP antibodies between patients with and without in vivo-bound ANA was observed. Consequently, there was a strong association of in vivo-bound ANA and anti-RNP antibodies (p < 0.01). In SLE patients with in vivo-bound ANA the incidence of nephropathy was significantly lower (p < 0.01), regardless of LBT positivity. In SLE patients there were no differences in LBT positivity, anti-dsDNA antibodies and complement consumption between groups. CONCLUSION: Our study implies that the presence of speckled ANA in keratinocytes in LBT may be useful in the diagnosis of MCTD and in the prognosis of renal involvement, especially in SLE patients.


Assuntos
Anticorpos Antinucleares/metabolismo , Queratinócitos/metabolismo , Lúpus Eritematoso Cutâneo/metabolismo , Adulto , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Humanos , Imunoglobulina G/análise , Queratinócitos/imunologia , Queratinócitos/patologia , Lúpus Eritematoso Cutâneo/imunologia , Lúpus Eritematoso Cutâneo/patologia , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/metabolismo , Masculino , Doença Mista do Tecido Conjuntivo/imunologia , Doença Mista do Tecido Conjuntivo/metabolismo , Prognóstico , Síndrome de Sjogren/imunologia , Síndrome de Sjogren/metabolismo , Coloração e Rotulagem
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