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1.
Anim Genet ; 49(6): 641-644, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30246406

RESUMO

Ehlers-Danlos syndrome (EDS) is a group of heritable connective tissue disorders caused by defective collagen synthesis or incorrect assembly of the collagen triple helical structure. EDS is characterised by joint hypermobility, skin hyperextensibility, abnormal scarring, poor wound healing and tissue friability. Human EDS may be caused by variants in several different genes including COL5A1, which encodes the collagen type V alpha 1 chain. For the present study we investigated a 1.5-year-old, spayed female, domestic shorthair cat with EDS. The affected cat showed multiple recurrent skin tears, hyperextensibility of the skin and joint abnormalities. We obtained whole genome sequencing data from the affected cat and searched for variants in candidate genes known to cause EDS. We detected a heterozygous single base-pair deletion in exon 43 of the COL5A1 gene, namely c.3420delG. The deletion was predicted to result in a frameshift and premature stop codon: p.(Leu1141SerfsTer134). Sanger sequencing confirmed that the variant was present in the affected cat and absent from 103 unaffected cats from different breeds. The variant was also absent from a Burmese cat with EDS. Based on knowledge about the functional impact of COL5A1 variants in other species, COL5A1:c.3420delG represents a compelling candidate causative variant for the observed EDS in the affected cat.


Assuntos
Doenças do Gato/genética , Gatos/genética , Colágeno Tipo V/genética , Síndrome de Ehlers-Danlos/veterinária , Mutação da Fase de Leitura , Animais , Códon sem Sentido , Síndrome de Ehlers-Danlos/genética , Éxons , Deleção de Sequência , Anormalidades da Pele
2.
Allergy ; 66(8): 1030-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21385183

RESUMO

BACKGROUND: Intravenous immunoglobulin (IVIG) preparations are increasingly used for the treatment of autoimmune and chronic inflammatory diseases. Naturally occurring autoantibodies against Siglec-9 and Fas are thought to contribute to the anti-inflammatory effects of IVIG via cell death regulation of leukocytes and tissue cells. Dimeric IVIG fractions are suspected to contain idiotypic (Id)-anti-idiotypic complexes of antibodies, which might also include anti-Siglec-9 and anti-Fas autoantibodies. METHODS: Dimeric IVIG fractions were separated from monomeric IVIG by size-exclusion chromatography and remonomerized by low pH treatment. Binding studies of total, monomeric, and dimeric IVIG were performed using surface plasmon resonance and flow cytometry on primary human neutrophils. RESULTS: Anti-Siglec-9 and anti-Fas autoantibodies were contained in both monomeric and dimeric IVIG fractions, but anti-Siglec-9 antibodies were highly enriched in dimeric IVIG. The propensity to engage in dimer formation was paratope dependent. IVIG binding to Siglec-9 was specific and sialylation independent. Interestingly, we detected anti-idiotypic antibodies (anti-Ids) against anti-Siglec-9 autoantibodies in dimeric, but not in monomeric fractions of IVIG. CONCLUSIONS: Our study supports the concept that idiotype-anti-idiotype (Id-anti-Id) interactions contribute to the dimer formation in IVIG preparations. To our knowledge, this is the first description of Id-anti-Id dimers of death receptor-specific antibodies in IVIG. Such Id-anti-Id interactions might determine the activity of immunomodulatory antibodies present both in IVIG and the patient.


Assuntos
Antígenos CD/imunologia , Autoanticorpos/análise , Idiótipos de Imunoglobulinas/análise , Imunoglobulinas Intravenosas/análise , Lectinas/imunologia , Humanos , Imunoglobulinas Intravenosas/imunologia , Neutrófilos , Multimerização Proteica , Lectinas Semelhantes a Imunoglobulina de Ligação ao Ácido Siálico , Receptor fas/imunologia
3.
Vox Sang ; 97(4): 348-54, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19656348

RESUMO

BACKGROUND AND OBJECTIVES: Complement inhibition is considered important in the mechanism of action of intravenous immunoglobulin (IVIG) in a number of inflammatory and autoimmune disorders. The capacity of different IVIG preparations to 'scavenge' activated C3 and thereby inhibit complement activation was assessed by a new in vitro assay. MATERIALS AND METHODS: Diluted human serum as a complement source, with or without addition of different concentrations of IVIG, was incubated in microtitre plates coated with heat-aggregated human IgG. Complement scavenging was measured by detecting reduced C3 binding and determining fluid phase C3b-IgG complex formation. Complement activation induced by the IVIG preparations was measured as C5a formation. RESULTS: All IVIG preparations exhibited a dose-dependent inhibition of C3b deposition, correlating strongly with binding of C3b to fluid-phase IgG, but the extent of complement scavenging varied considerably between different IVIG preparations. At an IVIG concentration of 0.9 mg/ml, the inhibition of C3b deposition ranged from 72 +/- 16% to 22 +/- 4.1%. The reduction of C3b deposition on the complement-activating surface was not due to IVIG-induced complement activation in the fluid phase, as shown by the low C5a formation in the presence of serum. CONCLUSION: In vitro analysis allows comparison of the complement-inhibitory properties of IVIG preparations. The extent of complement scavenging varies between the products.


Assuntos
Ativação do Complemento , Complemento C3a/química , Complemento C5a/análise , Imunoglobulinas Intravenosas/análise , Complemento C3a/imunologia , Complemento C5a/imunologia , Testes de Fixação de Complemento/métodos , Relação Dose-Resposta Imunológica , Humanos , Imunoglobulinas Intravenosas/imunologia
4.
Transfus Med ; 14(2): 165-71, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15113381

RESUMO

In this first-in-man study, we assessed the pharmacokinetics, safety and tolerability of MonoRho, a human recombinant monoclonal anti-RhD immunoglobulin G1 (IgG1) antibody. Eighteen RhD-negative healthy male volunteers were randomized in two groups to receive a single administration of 300 micro g of MonoRho either intravenously or intramuscularly. There were no symptoms of allergic or anaphylactic type reaction in any subject, and there was no evidence of any MonoRho-related changes in laboratory safety parameters. None of the subjects mounted a detectable immune response to MonoRho. Serum samples were obtained up to 91 days after injection to measure anti-D IgG concentrations by flow cytometry. After intramuscular administration of MonoRho, anti-D IgG concentrations gradually increased reaching peak levels after a mean of 3.4 days. After 3 weeks, the mean anti-D IgG concentrations after intravenous and intramuscular administration became virtually equal to each other and remained so thereafter. In both the treatment groups, the mean elimination half-life was about 18 days and thus similar to that described for plasma-derived anti-D IgG. The bioavailability of MonoRho after intramuscular administration was estimated as 46%. The excellent tolerability and safety of MonoRho as well as its expected elimination half-life supports the continued clinical development of this compound.


Assuntos
Anticorpos Monoclonais/farmacocinética , Fragmentos de Imunoglobulinas/administração & dosagem , Isoanticorpos/sangue , Sistema do Grupo Sanguíneo Rh-Hr/imunologia , Adulto , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Disponibilidade Biológica , Meia-Vida , Humanos , Fragmentos de Imunoglobulinas/efeitos adversos , Imunoglobulina G , Masculino , Farmacocinética , Proteínas Recombinantes/administração & dosagem , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/farmacocinética
5.
Dermatology ; 203(1): 60-2, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11549803

RESUMO

Pili anulati are defined by characteristic alternating light and dark banding in the hair shaft, due to air-filled spaces between the macrofibrillar units of the hair cortex, and are regarded as a congenital hair shaft disorder without increased hair fragility. Two cases of pili anulati are presented, in which fragility of hair developed in a causal relationship with the onset of androgenetic alopecia. Accordingly, trichorrhexis-nodosa-like hair fracturing was exclusively limited to the androgenetic region. In general, secondary trichorrhexis nodosa is an unspecific finding related to excess stress of hair in relation to its fragility. With onset of hair thinning due to androgenetic alopecia, progressive reduction of hair shaft diameter may cause increased fragility in pili anulati. In this case, hair shaft fracturing occurs within the area of androgenetic alopecia and colocalizes with the air-filled cavities of pili anulati.


Assuntos
Alopecia/etiologia , Cabelo/anormalidades , Adulto , Alopecia/patologia , Feminino , Cabelo/diagnóstico por imagem , Humanos , Ultrassonografia
6.
Am J Med Genet ; 100(2): 122-9, 2001 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-11298373

RESUMO

A boy presented at age 3.5 months with joint contractures, restlessness, and pain on handling. His skin was thickened and there were livid-red macular lesions over bony prominences. Infantile systemic hyalinosis (ISH) was diagnosed, a presumably autosomal recessive, progressive, and painful disorder of as yet unknown pathogenesis. Observation over three years confirmed the diagnosis as typical changes, such as nodules on both ears, pearly papules in the perinasal folds and on the neck, fleshy nodules in the perianal region, and gingival hypertrophy, developed. Skin lesions and painful joint contractures progressed in spite of intense physiotherapy, and at age 3, the child had marked motor disability. The central nervous system (CNS) appeared to be intact and the infant showed normal mental development. Radiologic findings included marked generalized osteopenia, osteolytic erosions in the metaphyses of the long bones, and cortical thinning. Electron microscopy of two skin biopsies demonstrated deposition of floccular amorphous substance that was abundant around, and appeared to originate from, small blood vessels in the dermis, partially interfering with collagen fiber formation. Lysosomal inclusions were not seen. Serum acid hyaluronidase activity was within the normal range, and the synthesis of hyaluronic acid and proteoglycans in cultured skin fibroblasts was similar to that of control cells. A younger sister presented at age two months with painful joint contractures and discrete livid-red macules over both malleoli, and showed a similar progression of the disorder over the first year of life. The diagnosis of ISH should be considered in infants and children presenting with painful joint contractures and skin lesions. The pathogenesis of this disabling and disfiguring disorder remains unclear. Our data confirm probable autosomal recessive inheritance, and do not support lysosomal storage, hyaluronidase deficiency, or a primary collagen disorder, but indicate that the amorphous material accumulating in the skin and articular soft tissues may originate from the blood circulation.


Assuntos
Hialuronoglucosaminidase/sangue , Artropatias/congênito , Dermatopatias/congênito , Células Cultivadas , Pré-Escolar , Contratura/patologia , Fibroblastos/metabolismo , Humanos , Ácido Hialurônico/metabolismo , Artropatias/sangue , Artropatias/diagnóstico por imagem , Masculino , Osteólise/congênito , Proteoglicanas/metabolismo , Radiografia , Dermatopatias/sangue , Dermatopatias/diagnóstico por imagem
7.
Hautarzt ; 52(1): 51-5, 2001 Jan.
Artigo em Alemão | MEDLINE | ID: mdl-11220240

RESUMO

In 1956 Klingmüller first described the trichorhinophalangeal syndrome (TRPS), which was named by Giedion ten years later. The syndrome includes a combination of typical hair, facial and bone abnormalities with variable expression allowing the further distinction of three subtypes. In a 37-year old patient with TRPS type I who reportedly had reduced hair growth length, clinically fine and brittle hair were found. Scanning electron microscopy revealed widely spaced cuticular scales. Quantitative measurement of the biomechanical properties of the hair showed a significant increase in the viscous parameter. This could be a result of decreased disulfide bridges and increased halogen bonds in the keratin matrix of the hair. In dermatological practice patients with TRPS often present because of hair abnormalities. Because of premature arthrosis due to skeletal abnormalities, occupational counseling is advised.Congenital heart problems, kidney abnormalities and endocrinological problems are rare, but should be sought in the symptomatic individual. Apart from mild hair care and avoidance of additional physical or chemical injuries due to hair cosmetic procedures,there is no treatment for the hair defects.


Assuntos
Cabelo/anormalidades , Síndrome de Langer-Giedion/diagnóstico , Osteocondrodisplasias/diagnóstico , Adulto , Fenômenos Biomecânicos , Diagnóstico Diferencial , Elasticidade , Feminino , Cabelo/fisiologia , Cabelo/ultraestrutura , Mãos/diagnóstico por imagem , Humanos , Síndrome de Langer-Giedion/diagnóstico por imagem , Microscopia Eletrônica de Varredura , Osteocondrodisplasias/diagnóstico por imagem , Radiografia , Viscosidade
8.
Anticancer Res ; 21(5): 3253-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11848480

RESUMO

BACKGROUND: The aim of this study was to develop and characterize a mouse xenograft model for the hypercalcemic-type of small cell carcinoma of the ovary (HTSCCO). PATIENTS AND METHODS: Tumor fragments were removed from a patient and cultured in six subsequent generations of nude mice. Histology, comparative genomic hybridization (CGH), electron microscopy and serum calcium levels were investigated. RESULTS: Morphology remained the same from the primary tumor of the patient through the 6th passage in the mouse. Serum calcium levels were significantly higher in the tumor-bearing mice compared to controls. CGH of the HTSCCO did not show evidence of a close relationship to either a germ cell tumor or an epithelial ovarian cancer. CONCLUSION: Some evidence was provided that the HTSCCO is an inhomogeneous tumor that is neither related to a germ cell tumor nor to an epithelial ovarian cancer, but is a distinct tumor entity.


Assuntos
Carcinoma de Células Pequenas/patologia , Hipercalcemia/patologia , Neoplasias Ovarianas/patologia , Células Tumorais Cultivadas , Adulto , Animais , Cálcio/sangue , Carcinoma de Células Pequenas/sangue , Carcinoma de Células Pequenas/genética , Divisão Celular/fisiologia , Aberrações Cromossômicas , Feminino , Humanos , Hipercalcemia/sangue , Hipercalcemia/genética , Camundongos , Camundongos Nus , Microscopia Eletrônica , Transplante de Neoplasias , Hibridização de Ácido Nucleico , Neoplasias Ovarianas/sangue , Neoplasias Ovarianas/genética , Transplante Heterólogo
9.
J Clin Pharmacol ; 40(7): 722-30, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10883413

RESUMO

In this randomized, double-blind, parallel-group study, a commercially available human immunoglobulin-G product, IVIG, was compared with two test formulations: (1) IVIG-N, which is a nanofiltered formulation of IVIG, and (2) IVIG-L, which is a nanofiltered, liquid, ready-for-use IgG formulation containing nicotinamide, L-proline, and L-isoleucine as stabilizers. Three groups of 10 healthy subjects each received a single 0.6 g/kg dose of one of the formulations infused over 3.5 to 6.8 hours, depending on the total volume to be infused. Blood samples were obtained over a 6-week period to assess pharmacokinetics, immunogenicity, and the pharmacodynamic effects on leukocytes and TNF-alpha. A blood sample was taken at 6 months for a viral safety check. Administrations were generally well tolerated with only one reference IVIG infusion stopped prematurely due to headache. The IgG Cmax and AUC over the 6-week blood sampling period from both test formulations satisfied equivalence criteria compared with the reference formulation. In subjects receiving IVIG-L, peak concentrations of the stabilizer nicotinamide ranged from 0.34 to 0.47 mmol/L and of nicotinamide-N-oxide from 0.03 to 0.04 mmol/L, which are below those reported to cause adverse events. During the infusion of IVIG, leukocyte counts initially declined from a baseline of 5.7 +/- 1.1 x 10(9)/L to 3.7 +/- 0.8 x 10(9)/L at 2 to 4 hours and returned to baseline by 24 hours. TNF-alpha levels, reflecting activation of the monocyte-macrophage system by the infused IVIG, rose from a baseline of 13 +/- 4 pg/mL to a peak of 272 +/- 324 pg/mL at 2 to 4 hours and returned to baseline by 24 hours. These patterns were generally similar for the test formulations, with the exception that the increase in TNF-alpha levels was dampened for IVIG-N, although this was not statistically significant. There was no evidence of immunogenicity or viral transmission from any of the formulations. Hence, these three formulations were generally well tolerated, yielded similar systemic exposure to IgG over a 6-week period after administration, and did not give rise to immunogenicity or viral safety concerns.


Assuntos
Imunoglobulina G/farmacologia , Imunoglobulinas Intravenosas/farmacologia , Adolescente , Adulto , Química Farmacêutica , Método Duplo-Cego , Excipientes/análise , Feminino , Anticorpos Anti-Hepatite B/administração & dosagem , Anticorpos Anti-Hepatite B/farmacologia , Humanos , Imunidade/efeitos dos fármacos , Imunoglobulina G/administração & dosagem , Imunoglobulina G/efeitos adversos , Imunoglobulina G/metabolismo , Imunoglobulinas Intravenosas/administração & dosagem , Imunoglobulinas Intravenosas/efeitos adversos , Imunoglobulinas Intravenosas/metabolismo , Infusões Intravenosas , Isoleucina/sangue , Isoleucina/urina , Contagem de Leucócitos/efeitos dos fármacos , Masculino , Niacinamida/sangue , Niacinamida/urina , Prolina/sangue , Prolina/urina , Fator de Necrose Tumoral alfa/metabolismo
10.
Appl Environ Microbiol ; 65(11): 4734-40, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10543779

RESUMO

The effect of selenite on growth kinetics, the ability of cultures to reduce selenite, and the mechanism of detoxification of selenium were investigated by using Rhodospirillum rubrum. Anoxic photosynthetic cultures were able to completely reduce as much as 1. 5 mM selenite, whereas in aerobic cultures a 0.5 mM selenite concentration was only reduced to about 0.375 mM. The presence of selenite in the culture medium strongly affected cell division. In the presence of a selenite concentration of 1.5 mM cultures reached final cell densities that were only about 15% of the control final cell density. The cell density remained nearly constant during the stationary phase for all of the selenite concentrations tested, showing that the cells were not severely damaged by the presence of selenite or elemental selenium. Particles containing elemental selenium were observed in the cytoplasm, which led to an increase in the buoyant density of the cells. Interestingly, the change in the buoyant density was reversed after selenite reduction was complete; the buoyant density of the cells returned to the buoyant density of the control cells. This demonstrated that R. rubrum expels elemental selenium across the plasma membrane and the cell wall. Accordingly, electron-dense particles were more numerous in the cells during the reduction phase than after the reduction phase.


Assuntos
Rhodospirillum rubrum/fisiologia , Selênio/metabolismo , Selenito de Sódio/metabolismo , Inativação Metabólica , Cinética , Luz , Fotossíntese , Rhodospirillum rubrum/efeitos dos fármacos , Rhodospirillum rubrum/ultraestrutura , Selênio/farmacologia , Selenito de Sódio/farmacologia
12.
Arch Intern Med ; 159(13): 1473-80, 1999 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-10399899

RESUMO

BACKGROUND: Persons infected with human immunodeficiency virus (HIV) are at increased risk for diarrhea and enteric infections. We studied (1) the epidemiology of enteric pathogens associated with diarrhea, (2) the diagnostic yield of stool examination and endoscopic evaluation, (3) risks to develop diarrhea, and (4) the impact of diarrhea on patients' survival. METHODS: A total of 1933 participants in the Swiss HIV Cohort Study were prospectively followed up for a median of 25.5 months. A total of 560 diarrheal episodes were evaluated by standardized stool examination. Endoscopic evaluation was performed in 25% of patients with chronic diarrhea. RESULTS: The incidence of diarrhea was 14.2 per 100 person-years (95% confidence interval, 13.0-15.4). Among patients with CD4 cell counts below 0.05 x 10(9)/L, the probability to develop diarrhea within 1, 2, and 3 years was 48.5%, 74.3%, and 95.6%, respectively. The risk to develop diarrhea was increased among patients with severe immunodeficiency, homosexual men, and patients taking antiretroviral therapy. Pneumocystis carinii chemoprophylaxis did not reduce the risk of diarrhea. Diarrhea was an independent negative predictor of survival. Enteric pathogens were detected in 16.5% of 212 acute diarrheal episodes and in 46% of 348 chronic diarrheal episodes. The sensitivity of histological and stool examination was similar except for the diagnosis of intestinal cytomegalovirus infection and leishmaniasis, which required invasive evaluation. CONCLUSIONS: Intestinal infections were diagnosed in less than 50% of chronic diarrheal episodes. The prevalence of enteric pathogens tended to decrease during the observation period, possibly because of improved antiretroviral therapy. Endoscopic evaluation did not improve the diagnostic yield compared with stool examination except for the diagnosis of cytomegalovirus enteritis and leishmaniasis.


Assuntos
Infecções Oportunistas Relacionadas com a AIDS/microbiologia , Diarreia/microbiologia , Enterite/microbiologia , Infecções Oportunistas Relacionadas com a AIDS/complicações , Infecções Oportunistas Relacionadas com a AIDS/diagnóstico , Infecções Oportunistas Relacionadas com a AIDS/parasitologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Diarreia/parasitologia , Diarreia/virologia , Endoscopia Gastrointestinal , Enterite/complicações , Enterite/diagnóstico , Enterite/parasitologia , Enterite/virologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Risco , Fatores de Risco
13.
Ann Chir Main Memb Super ; 18(1): 66-72, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10941397

RESUMO

The non-cemented Ledoux trapeziometacarpal prosthesis has a high failure rate. In order to better understand the mechanism responsible for pain and loosening, we thoroughly analysed the membranes surrounding the prosthesis and the bone-prosthesis interface in two trapezia, each containing a Ledoux cup, which were resected after unsuccessful implantation. Serial sections, perpendicular to the longitudinal axis of the implanted cup, allowed histological examination of the interface and were used to quantify bone apposition. The tissues surrounding the prosthesis showed a foreign-body reaction to particles identified as titanium. The interface showed bony integration of the cup, mainly on the radial side and on the proximal part of the cup, with an appositional index of 28%. Our findings suggest that bony apposition might not be sufficient to ensure successful anchoring of the Ledoux cup in the trapezium in the presence of an intense foreign body reaction to titanium. Moreover, the presence of metal might be secondary to micromotion of the wings of the metallic part of the cup, induced by axial movement of the underlying polyethylene during pinch grip. The combination of polyethylene as an expander and titanium may need to be reviewed.


Assuntos
Prótese Articular , Metacarpo/cirurgia , Humanos , Metacarpo/anatomia & histologia
14.
Pathol Int ; 48(11): 912-6, 1998 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-9832063

RESUMO

A case of lipid-rich mammary carcinoma identified in a lumpectomy specimen from a 56-year-old female is presented. The tumor showed features of poorly differentiated invasive ductal carcinoma of clear-cell phenotype. Cytoplasmic lucency was mainly accounted for by the accumulation of neutral fat and, to a lesser degree, glycogen. Tinctorial properties included positivity of tumor cells with Sudan III dye and diastase-sensitive periodic acid-Schiff staining. Ultrastructural examination confirmed the presence of abundant cytoplasmic lipid droplets and some glycogen rosettes. On immunohistochemistry, most tumor cells reacted for cytokeratin, vimentin and S-100 protein, and there was focal expression of carcinoembryogenic antigen. A minority of tumor cell nuclei expressed progesterone receptors. As an additional feature, part of the lesion exhibited chondroid metaplasia. Lipid-rich carcinoma of the breast is exceedingly rare and, to our knowledge, no such example harboring metaplastic elements has been described previously.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Lipídeos/análise , Biópsia por Agulha , Neoplasias da Mama/química , Neoplasias da Mama/ultraestrutura , Carcinoma Ductal de Mama/química , Carcinoma Ductal de Mama/ultraestrutura , Feminino , Humanos , Metaplasia/patologia , Microscopia Eletrônica , Pessoa de Meia-Idade
15.
Thromb Haemost ; 80(2): 316-20, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9716159

RESUMO

A reconstituted high density lipoprotein (rHDL) prepared for clinical use was tested for its influence on platelet activity modulated by various stimuli. In a first series of in vitro experiments, rHDL was added to blood in a concentration series, and platelet rich plasma (PRP) was isolated. Platelets were stimulated with arachidonic acid, collagen, epinephrine or ADP, and platelet aggregation was assessed. rHDL mediated a dose dependent inhibition of the platelet activity. With purified platelets rHDL inhibited the release reaction induced by collagen, but not by thrombin, as measured by CD62P (P-Selectin) expression on the plasma membrane. Ex vivo experiments were performed with PRP from volunteers, previously infused with 25 mg rHDL/kg body weight and 40 mg rHDL/kg body weight, respectively. Platelet activity in PRP was assessed before, and up to 30 h after the end of the rHDL infusion. A transient inhibition of the platelet aggregation induced by arachidonic acid and collagen was observed which was more pronounced in the group receiving 40 mg rHDL/kg body weight. In both groups of experiments, in vitro and ex vivo, the inhibition of the platelet activity was also dependent on the stimulus used.


Assuntos
Lipoproteínas HDL/farmacologia , Inibidores da Agregação Plaquetária/farmacologia , Humanos , Infusões Intravenosas , Lipídeos/sangue , Masculino , Valores de Referência
16.
J Cutan Pathol ; 25(5): 275-8, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9696294

RESUMO

The histopathology of the lupus-like skin lesions associated with Bloom syndrome has been sporadically described. Skin biopsies from a 2-year-old boy with the classical features of Bloom syndrome, including lupus-like skin lesions, demonstrated marked interface changes with basal liquefaction degeneration, a moderate superficial mononuclear infiltrate, pigmentary incontinence, and capillary dilation in the papillary dermis. Immunophenotyping of the dermal infiltrate revealed predominance of T-cells. Basement membrane thickening on periodic acid-Schiff examination was not seen. Direct immunofluorescence failed to demonstrate deposits of immunoglobulin other than nonspecific IgM deposition along the basement membrane zone of lesional skin. Ultrastructurally, the most striking findings were disintegration of basal cell cytoplasm and tubuloreticular inclusions in vascular endothelia. Taken together, the histologic and ultrastructural features of lupus-like lesions associated with Bloom syndrome mimic those of cutaneous lupus erythematosus, with the exception of paucity of immune deposits at the dermoepidermal junction.


Assuntos
Síndrome de Bloom/patologia , Lúpus Eritematoso Cutâneo/patologia , Pele/patologia , Membrana Basal/metabolismo , Membrana Basal/ultraestrutura , Síndrome de Bloom/metabolismo , Pré-Escolar , Endotélio Vascular/ultraestrutura , Epiderme/ultraestrutura , Técnica Direta de Fluorescência para Anticorpo , Humanos , Imunoglobulina M/metabolismo , Lúpus Eritematoso Cutâneo/metabolismo , Masculino , Microscopia Eletrônica , Pele/irrigação sanguínea , Pele/metabolismo , Células-Tronco/ultraestrutura
17.
Vox Sang ; 75(4): 278-87, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9873263

RESUMO

BACKGROUND AND OBJECTIVES: Hyperimmune anti-Rh D serum is worldwide in short supply. As a first step to develop an alternative source of Rh D antibodies, we describe in this study the isolation and characterization of recombinant anti-Rh D Fab fragments. MATERIALS AND METHODS: Peripheral blood mononuclear cells harvested from a hyperimmunized donor were used to construct two combinatorial Fab libraries. Phages expressing these Fab fragments were selected on whole red blood cells followed by testing of positive clones in an indirect hemagglutination assay. RESULTS: Individual Fab clones are of high affinity and competitively inhibit the binding of a registered anti-D immunoglobulin. The Fab clones are also specific against the partial D phenotypes, Rh33, DIII, DIVa, DIVb, DVa, and DVII. The 13 different but highly homologous clones express preferentially VH3 segments. CONCLUSION: These Fab fragments show potential for the development of a new generation of therapeutic anti-Rh D reagents.


Assuntos
Bacteriófagos/genética , Testes de Hemaglutinação , Fragmentos Fab das Imunoglobulinas , Biblioteca de Peptídeos , Imunoglobulina rho(D)/imunologia , Sequência de Aminoácidos , Clonagem Molecular , Humanos , Masculino , Dados de Sequência Molecular , Proteínas Recombinantes/imunologia , Sensibilidade e Especificidade
18.
Shock ; 7(3): 175-81, 1997 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9068082

RESUMO

A reconstituted high density lipoprotein (rHDL) containing human apolipoprotein A-I and phosphatidylcholine was tested for its ability to modify polymorphonuclear leukocyte (PMN) adherence to endothelial cells (EC) in vitro. EC stimulation for 4 h with lipopolysaccharide (LPS) or tumor necrosis factor-alpha (TNF alpha) resulted in a four- to sixfold increase in PMN adherence. Concomitant stimulation of EC with LPS and rHDL virtually prevented the LPS-stimulated increase in PMN adherence. Changes in adherence were paralleled by alterations in adhesion molecule expression of EC. Concomitant EC stimulation with LPS and rHDL resulted in complete inhibition of the LPS-stimulated increase in expression of E-selectin and intercellular adhesion molecule 1 (ICAM-1). In contrast, rHDL reduced the TNF alpha-induced expression of adhesion molecules as well as the PMN adherence to TNF alpha-stimulated EC by approximately 10%. The CD11/CD18-mediated PMN adherence to EC as a consequence of PMN stimulation with calcium ionophore (A23187) was diminished in the presence of rHDL after 7 min incubation by 36.1 +/- 11.4% and after 15 min incubation by 45.1 +/- 7.4%. In addition, the A23187-stimulated increase in PMN adherence to fibrinogen-coated surfaces, mediated by CD11b/CD18, was virtually eliminated in the presence of rHDL and HDL, but not in the presence of apolipoprotein A-I or natural low density lipoprotein. FACS analysis showed that PMN treated with rHDL and subsequently washed were resistant to FMLP-induced CD11b/ CD18 up-regulation. In conclusion, these data indicate that rHDL decreases cell adhesion via two mechanisms: blocking LPS activity and modifying CD11b/CD18 up-regulation on PMN.


Assuntos
Endotélio Vascular/citologia , Lipoproteínas HDL/fisiologia , Neutrófilos/citologia , Apolipoproteína A-I/farmacologia , Antígenos CD11/metabolismo , Antígenos CD18/metabolismo , Calcimicina/farmacologia , Adesão Celular/fisiologia , Células Cultivadas , Selectina E/metabolismo , Fibrinogênio/farmacologia , Humanos , Integrinas/metabolismo , Molécula 1 de Adesão Intercelular/biossíntese , Lipopolissacarídeos/farmacologia , Antígeno de Macrófago 1/metabolismo , N-Formilmetionina Leucil-Fenilalanina/farmacologia , Neutrófilos/imunologia , Fator de Necrose Tumoral alfa/farmacologia
19.
Dermatology ; 194(2): 191-4, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-9094476

RESUMO

Several clinical syndromes are characterized by ectodermal dysplasia (ED) in association with clefting of the lip and/or palate. In these syndromes, alopecia is primarily due to abnormalities of the hair shaft associated with increased hair fragility. Scalp dermatitis is yet another peculiar finding, primarily seen in the ankyloblepharon-ED-clefting (AEC) syndrome. We report on a 16-year-old patient with ectrodactyly-ED-clefting (EEC) syndrome, who exhibited a scarring alopecia due to deep folliculitis. On scanning electron microscopy, irregular torsion and longitudinal grooving of the hair shaft (pili torti et canaliculi) were observed. Quantitative determinations of the elastic and viscous parameters of hair demonstrated a normal viscosity but a significantly reduced hair elasticity, indicating either an abnormal composition or a disordered arrangement of microfibrils within the apparently normal keratin matrix. In contrast to the erosive scalp dermatitis of early onset in the AEC syndrome, alopecia in this case of EEC syndrome demonstrated follicular scarring with onset during puberty. We question a possible role of the anatomical hair abnormality in the pathogenesis of chronic deep folliculitis in this and clinically related syndromes.


Assuntos
Alopecia/patologia , Cicatriz/patologia , Fenda Labial/patologia , Fissura Palatina/patologia , Displasia Ectodérmica/patologia , Dedos/anormalidades , Foliculite/patologia , Cabelo/anormalidades , Adolescente , Fenômenos Biofísicos , Biofísica , Dermatomicoses/patologia , Elasticidade , Humanos , Queratinas/análise , Malassezia/isolamento & purificação , Masculino , Microscopia Eletrônica de Varredura , Puberdade , Dermatoses do Couro Cabeludo/microbiologia , Dermatoses do Couro Cabeludo/patologia , Infecções Cutâneas Estafilocócicas/patologia , Síndrome , Viscosidade
20.
Pneumologie ; 51(12): 1127-32, 1997 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-9487775

RESUMO

BACKGROUND: In adults suffering from Kartagener's syndrome-which is found in 50% of patients with primary ciliary dyskinesia (PCD)-bronchiectasis is still one of three typical clinical features. In this condition it is caused by chronic bacterial inflammation as a result of impaired mucociliary clearance in congenital ciliary dysfunction. Little information is available on the incidence, age-related development and prophylactic therapy of bronchiectasis in children suffering from PCD. CASE REPORT/RESULTS: We describe the case of a 2-year old boy with clinical features of Kartagener's syndrome who showed impaired ciliary motility and typical ultrastructural defects of PCD. Bronchiectasis was excluded by bronchography. CONCLUSIONS: The diagnosis of PCD implies disturbed ciliary motility and abnormal ultrastructure of the cilia. In 50% of cases PCD is associated with situs inversus and is then referred to as kartagener's syndrome, whereas situs inversus itself does not define Kartagener's syndrome. Bronchiectasis is not necessarily present in children with PCD. Physiotherapy, inhalations, vaccinations and early antibiotic treatment may be of prophylactic value in preventing bronchiectasis. Early start of the life-long treatment depends on early diagnosis which should be based on well-defined criteria.


Assuntos
Transtornos da Motilidade Ciliar/complicações , Síndrome de Kartagener/diagnóstico , Situs Inversus/complicações , Envelhecimento , Pré-Escolar , Humanos , Masculino , Fatores de Tempo
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