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1.
Int J Cosmet Sci ; 40(6): 583-588, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30447108

RESUMO

OBJECTIVE: Sex-related differences in skin properties may be expected to impact dandruff formation and treatment. A meta-analysis approach was undertaken to investigate potential differences between males and females in response to zinc pyrithione (ZnPT) treatment vs. non-anti-dandruff (AD) shampoo. A separate pooled statistical analysis of ceramide and total protein loss endpoints was also undertaken to assess potential sex-related differences in stratum corneum properties that might influence response to ZnPT vs. non-AD shampoo in subjects with dandruff. METHODS: The meta-analysis approach included data from 17 half-head, double-blind, randomized studies (N = 2088) undertaken in Asia to assess the effectiveness of 1% ZnPT shampoo and/or non-AD shampoo in reducing dandruff severity, as assessed by Total Weighted Head Score Adherent Flake (TWHS-AF) methodology. Treatment duration was 4 weeks, with TWHS-AF measured at weekly intervals. Data from an additional three studies (N = 143) conducted in Asia were included in the pooled analysis of ceramide levels and protein loss from scalp skin of subjects with dandruff. RESULTS: Response to 1% ZnPT vs. non-AD shampoo was greater in males than in females at all time points; after 4 weeks, the between-treatment difference in TWHS-AF was -17.5 (95% confidence interval [CI] -19.5, -15.5) in males and -11.1 (-13.2, -8.9) in females. Sex-related differences were observed between males and females in response to both 1% ZnPT and non-AD shampoos. Males had a stronger response than females to treatment with 1% ZnPT shampoo, while dandruff decreased to a greater extent in females than in males when using non-AD shampoo. Statistically significant sex-related differences in ceramide levels and total protein loss were observed (both P < 0.01). Ceramide levels were 0.76 times lower (95% CI 0.60, 0.97) in males than in females, while total protein loss was 1.4 times greater (95% CI 1.1, 1.9) in males than in females. CONCLUSION: Males show a greater response than females to 1% ZnPT shampoo, while females show a greater response than males to non-AD shampoo. These findings may in part be explained by the sex-related differences observed in stratum corneum properties, which may make males more prone to dandruff than females.


Assuntos
Caspa/prevenção & controle , Preparações para Cabelo , Compostos Organometálicos/farmacologia , Piridinas/farmacologia , Fatores Sexuais , Adulto , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
2.
Int J Cosmet Sci ; 36(1): 46-53, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23992282

RESUMO

OBJECTIVE: In humans, the process of hair shedding, referred to as exogen, is believed to occur independently of the other hair cycle phases. Although the actual mechanisms involved in hair shedding are not fully known, it has been hypothesized that the processes leading to the final step of hair shedding may be driven by proteases and/or protease inhibitor activity. In this study, we investigated the presence of proteases and protease activity in naturally shed human hairs and assessed enzyme inhibition activity of test materials. METHODS: We measured enzyme activity using a fluorescence-based assay and protein localization by indirect immunohistochemistry (IHC). We also developed an ex vivo skin model for measuring the force required to pull hair fibres from skin. RESULTS: Our data demonstrate the presence of protease activity in the tissue material surrounding club roots. We also demonstrated the localization of specific serine protease protein expression in human hair follicle by IHC. These data provide evidence demonstrating the presence of proteases around the hair club roots, which may play a role during exogen. We further tested the hypothesis that a novel protease inhibitor system (combination of Trichogen) and climbazole) could inhibit protease activity in hair fibre club root extracts collected from a range of ethnic groups (U.K., Brazil, China, first-generation Mexicans in the U.S.A., Thailand and Turkey) in both males and females. Furthermore, we demonstrated that this combination is capable of increasing the force required to remove hair in an ex vivo skin model system. CONCLUSION: These studies indicate the presence of proteolytic activity in the tissue surrounding the human hair club root and show that it is possible to inhibit this activity with a combination of Trichogen and climbazole. This technology may have potential to reduce excessive hair shedding.


Assuntos
Folículo Piloso/enzimologia , Serina Proteases/metabolismo , Inibidores de Serina Proteinase/farmacologia , Animais , Feminino , Folículo Piloso/efeitos dos fármacos , Humanos , Masculino , Suínos
3.
Int J Cosmet Sci ; 35(1): 78-83, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22970742

RESUMO

Dandruff is a common complaint and is suffered by as much as half of the population at some time post puberty. The condition is characterized by the presence of flakes on the scalp and in the hair, and is often accompanied by itch. The most common treatment for dandruff is the use of shampoo formulations that contain fungistatic agents such as zinc pyrithione (ZPT) and octopirox. Whilst most antidandruff shampoos are effective in resolving the symptoms of dandruff these shampoos can often result in hair condition that is less than acceptable to consumers which can lead to a tendency for them to revert to use of a non-antidandruff shampoo. This can result in a rapid return of dandruff symptoms. The aim of this investigation was to study the impact of using a combination of antidandruff actives and silicones on the resolution of dandruff and to deliver superior sensory properties to the hair. We have demonstrated that shampoo containing the dual active system of ZPT/Climbazole deposits both active agents onto a model skin surface (VitroSkin) and reduces Malassezia furfur regrowth in vitro. Clinical evaluation of the dual active shampoo demonstrated superior efficacy and retained superiority during a regression phase where all subjects reverted to using a non-antidandruff shampoo. We have also demonstrated that it is possible to deposit silicone materials from antidandruff shampoo uniformly over both virgin and damaged hair fibres that results in smoother hair fibres (as evidenced by reduced dry friction). This combination of antidandruff agents and conditioning silicones delivered from a shampoo provides subjects with superior antidandruff efficacy and desired end sensory benefits ensuring compliance and longer term dandruff removal.


Assuntos
Preparações para Cabelo , Imidazóis/farmacologia , Compostos Organometálicos/farmacologia , Piridinas/farmacologia , Humanos , Espectrometria por Raios X
4.
Int J Cosmet Sci ; 34(4): 298-306, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22515370

RESUMO

Dandruff is characterized by a flaky, pruritic scalp and affects up to half the world's population post-puberty. The aetiology of dandruff is multifactorial, influenced by Malassezia, sebum production and individual susceptibility. The commensal yeast Malassezia is a strong contributory factor to dandruff formation, but the presence of Malassezia on healthy scalps indicates that Malassezia alone is not a sufficient cause. A healthy stratum corneum (SC) forms a protective barrier to prevent water loss and maintain hydration of the scalp. It also protects against external insults such as microorganisms, including Malassezia, and toxic materials. Severe or chronic barrier damage can impair proper hydration, leading to atypical epidermal proliferation, keratinocyte differentiation and SC maturation, which may underlie some dandruff symptoms. The depleted and disorganized structural lipids of the dandruff SC are consistent with the weakened barrier indicated by elevated transepidermal water loss. Further evidence of a weakened barrier in dandruff includes subclinical inflammation and higher susceptibility to topical irritants. We are proposing that disruption of the SC of the scalp may facilitate dandruff generation, in part by affecting susceptibility to metabolites from Malassezia. Treatment of dandruff with cosmetic products to directly improve SC integrity while providing effective antifungal activity may thus be beneficial.


Assuntos
Dermatite Seborreica/microbiologia , Epiderme/metabolismo , Malassezia/crescimento & desenvolvimento , Sebo/metabolismo , Dermatite Seborreica/metabolismo , Epiderme/microbiologia , Humanos , Perda Insensível de Água
5.
Int J Cosmet Sci ; 29(1): 31-8, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18489309

RESUMO

Shaving the axilla is a regular part of the personal care regime for many women in Europe, North and South America. To assess the impact of shaving on underarm skin, a series of investigations were carried out, in which the thickness of the axillary vault and fossa were measured using optical coherence tomography (OCT), and underarm shaving debris was collected for study. The response of the axilla to histamine iontophoresis was also investigated. Additionally, a study was carried out to investigate the impact of a novel anti-perspirant roll-on formulation on irritation and self-perceived sensory properties of the axilla. The results clearly demonstrate that shaving the underarm consistently removes skin (stratum corneum) as well as axillary hair (with a mean value of 36.1% of the debris being skin). OCT measurements demonstrated that in shaved areas of the axilla, epidermal thickness is higher than in unshaved areas. In response to histamine, wheal and flare were both found to be greater in the shaved axilla, when compared with an unshaved control, but flare in the fossa was greater than that in the vault. On the basis of these results, we propose that the axillary vault has adapted to frequent shaving, notably by the development of a thickened epidermis. However, this adaptation is often not sufficient to fully protect the axilla from damage and irritation resulting from hair removal (shaving). In these instances, we have demonstrated that use of a novel anti-perspirant roll-on formulation containing glycerol and sunflower seed oil was able to reduce the impact of shaving-induced irritation and improve self-assessment of axillary condition.

7.
Anaesth Intensive Care ; 28(3): 293-9, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10853212

RESUMO

Quality assurance procedures are essential in the maintenance of clinical standards in medicine. Conventional analysis techniques have difficulty in detecting gradual changes over time. Cumulative sum techniques monitor the frequency with which an event occurs and can detect changes in its frequency as soon as they become statistically significant. This study explores the use of cumulative sum techniques to monitor the performance of an acute pain team in a teaching hospital. It shows that periods of suboptimal performance can be readily identified. The prospective use of these techniques in clinical audit may allow the earlier identification and correction of technical or organisational problems. These should lead to improvements in patient care and satisfaction.


Assuntos
Clínicas de Dor/normas , Garantia da Qualidade dos Cuidados de Saúde/métodos , Analgesia Epidural/efeitos adversos , Analgesia Epidural/normas , Analgesia Controlada pelo Paciente/efeitos adversos , Analgesia Controlada pelo Paciente/normas , Analgésicos Opioides/administração & dosagem , Analgésicos Opioides/efeitos adversos , Analgésicos Opioides/uso terapêutico , Bases de Dados como Assunto , Hospitais de Ensino/organização & administração , Hospitais de Ensino/normas , Humanos , Injeções Intravenosas , Auditoria Médica , Dor/prevenção & controle , Clínicas de Dor/organização & administração , Satisfação do Paciente , Estudos Prospectivos , Qualidade da Assistência à Saúde , Gestão da Qualidade Total , Resultado do Tratamento
8.
Clin Exp Metastasis ; 17(3): 183-92, 1999 May.
Artigo em Inglês | MEDLINE | ID: mdl-10432003

RESUMO

The selectins are a family of intercellular adhesion molecules that mediate the attachment of leukocytes to the endothelial lining of blood vessels. Another biological process that may involve selectins is the adhesion of circulating tumour cells to endothelium in cancer metastasis. This review discusses the evidence for the involvement of E-, P- and L-selectin in the metastasis of different tumour types. It is concluded that, with certain reservations and qualifications, selectins can play a role in metastasis. For example, the evidence for the involvement of E-selectin in breast and colon cancer metastasis is very strong. For the other selectins and tumour types the evidence is less convincing and further investigations are required to clarify the situation. Certainly, selectins are not the only mechanism available for tumours to metastasise. In the future, measurement of selectins could be useful prognostically and manipulation of their levels could lead to new cancer therapies.


Assuntos
Metástase Neoplásica/fisiopatologia , Selectinas/fisiologia , Animais , Biomarcadores Tumorais/fisiologia , Carcinoma/metabolismo , Carcinoma/patologia , Carcinoma/fisiopatologia , Bovinos , Adesão Celular/fisiologia , Humanos , Leucemia Experimental/metabolismo , Leucemia Experimental/patologia , Leucemia Experimental/fisiopatologia , Ligantes , Camundongos , Metástase Neoplásica/patologia , Selectinas/metabolismo , Células Tumorais Cultivadas
9.
Clin Exp Metastasis ; 17(7): 583-91, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10845557

RESUMO

The adhesion of tumour cells to the hyaluronan (HA) pericellular coat of mesothelial cells is an important step in the peritoneal spread of ovarian cancer. Previously, we have shown that the cell surface molecule CD44 is involved in this process. Paradoxically, the degree of adhesion does not appear to be related to the amount of CD44 expressed. In order to explain this observation we have examined the in vitro adhesion to HA of four high CD44-expressing ovarian cancer lines in relation to their CD44 spliced variant content and the CD44 glycosylation. Adhesion was measured in multiwell plates coated with different concentrations of HA in order to determine both the avidity and the maximum adhesion. Two lines had high adhesion and two lines had low adhesion. The avidity for HA was different for each line, but in all cases this could be totally blocked by treatment with an anti-CD44 antibody. The standard form of CD44 was the major species detected by RT/PCR in all lines and spliced variants were present in low amounts. Neuraminidase treatment increased the adhesion of the 'low-adhesion' lines at all HA coating concentrations; but only substantially increased the adhesion of the 'high-adhesion' lines at the lower HA coating concentrations. Tunicamycin treatment decreased the adhesion of the 'high-adhesion lines' at all HA coating concentrations and only substantially decreased the adhesion of one of the 'low-adhesion' lines when the plates were coated with a low concentration of HA. The adhesion of the remaining 'low-adhesion' line was slightly increased after tunicamycin treatment. It is concluded that glycosylation and not spliced variant content of CD44 affects the adhesive properties of ovarian tumour cells. This conclusion may have important consequences for developing new therapies in ovarian cancer.


Assuntos
Carcinoma Endometrioide/patologia , Moléculas de Adesão Celular/fisiologia , Adesão Celular , Cistadenocarcinoma Papilar/patologia , Receptores de Hialuronatos/fisiologia , Ácido Hialurônico/fisiologia , Glicoproteínas de Membrana/fisiologia , Metástase Neoplásica/fisiopatologia , Proteínas de Neoplasias/fisiologia , Neoplasias Ovarianas/patologia , Processamento de Proteína Pós-Traducional , Carcinoma Endometrioide/metabolismo , Moléculas de Adesão Celular/biossíntese , Cistadenocarcinoma Papilar/metabolismo , Feminino , Glicosilação/efeitos dos fármacos , Humanos , Receptores de Hialuronatos/biossíntese , Glicoproteínas de Membrana/biossíntese , Ácido N-Acetilneuramínico/química , Proteínas de Neoplasias/biossíntese , Neuraminidase/farmacologia , Neoplasias Ovarianas/metabolismo , Neoplasias Peritoneais/secundário , Ligação Proteica , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Células Tumorais Cultivadas , Tunicamicina/farmacologia
10.
Anaesth Intensive Care ; 27(6): 632-5, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10631419

RESUMO

Forty-three Acute Pain Service units in Australia and New Zealand were surveyed regarding data they collected on their daily rounds. The survey sought to determine what data each unit actually collected and what they considered to be a set of data that would be an acceptable minimal standard for the purpose of audit. The scoring or scaling mechanisms that were used in auditing the various parameters were also ascertained in an attempt to derive a consistent means of comparing data from the various Acute Pain Service groups. The Acute Pain Special Interest Group is currently developing suggestions for a standard data set and associated scoring mechanisms in line with the results of this survey.


Assuntos
Clínicas de Dor/estatística & dados numéricos , Manejo da Dor , Doença Aguda , Analgesia/efeitos adversos , Analgésicos/efeitos adversos , Austrália , Coleta de Dados , Humanos , Nova Zelândia
11.
Clin Cancer Res ; 4(9): 2095-102, 1998 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9748125

RESUMO

The mammalian pulmonary toxin 4-ipomeanol (IPO) is activated by the cytochrome P450 system in bronchial Clara cells in animals. The resulting metabolites bind rapidly to macromolecules, producing localized cytotoxicity. IPO has in vitro and in vivo antitumor activity in non-small cell lung cancer (NSCLC) and thus was proposed as a lung cancer-specific antitumor agent. We have completed a directed Phase I trial in patients with NSCLC. Forty-four patients (34 men and 10 women) with NSCLC were treated with IPO. All but two patients had an Eastern Cooperative Oncology Group performance status of 0 or 1. They received 91 courses of therapy with i.v. IPO; 82 courses were administered daily for five days, and 9 were single bolus doses. The dose-limiting toxicity of elevated serum transaminases was observed in three of seven patients at 922 mg/m2/day. The maximum tolerated dose was 693 mg/m2/day on 5 consecutive days every 3 weeks. One patient developed grade 4 pulmonary toxicity at 167 mg/m2/day. There was no significant hematological or renal toxicity. No objective antitumor responses were observed. Pharmacokinetic analysis of 39 patients from day 1 of IPO administration showed biexponential elimination with mean half-lives of 8.6 (alpha half-life) and 76 min (beta half-life). There was a linear relationship between the area under the plasma drug concentration-time curve and the dose of IPO. There was no significant difference between the pharmacokinetic parameters measured on day 1 and day 5. Using a 4-day in vitro cytotoxicity assay, two tumor cell lines established from patients treated at 693 mg/m2/day had IC50s of approximately 6 mM, a concentration more than 75-fold higher than the plasma levels measured in these patients. Thus, although the total amount of drug administered per cycle on a daily times five dose schedule is more than 2.5-fold higher than the recommended single daily dose, IPO is unlikely to be a useful drug for patients with lung cancer.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Terpenos/administração & dosagem , Adulto , Idoso , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Esquema de Medicação , Feminino , Humanos , Pneumopatias/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Tempo de Tromboplastina Parcial , Terpenos/efeitos adversos , Terpenos/farmacocinética
12.
J Immunol Methods ; 213(1): 19-30, 1998 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-9671122

RESUMO

Adherence may be an important virulence factor for Helicobacter pylori. Current methods available for quantitation of adherence are time consuming and liable to observer error. A new direct technique for fluorescent labelling of bacteria has been developed to quantitate adherence of H. pylori to epithelial cells by fluorescence activated cell sorting (FACS). Type strains of H. pylori, H. mustelae, H. cinaedi and H. fennelliae were grown microaerobically in broth culture for 24 h and fluorescently labelled by incubation with carboxyfluorescein diacetate succinimidyl ester (CFDA-SE) at 37 degrees C. After washing to remove excess CFDA-SE, bacteria were co-incubated (ratio 10:1) with gastric epithelial cells at 37 degrees C for up to 24 h. After washing to remove non-adherent bacteria, epithelial cells were detached with EDTA (2 mM) and fixed with formaldehyde for flow cytometry. Adherence was quantitated both in terms of the proportion of cells with adherent H. pylori and as the mean number of adherent bacteria per cell. All H. pylori strains adhered to gastric-type epithelial cells. The proportion of cells with bound bacteria varied from 40-99% and the number of bacteria per cell from 1-50, both of which correlated with microscopy (r = 0.6, and r = 0.8 respectively, n = 35). Time course studies demonstrated saturation of binding by H. pylori within 90 min. For H. mustelae, H. cinaedi and H. fennelliae the proportion of cells with bound bacteria varied from 5-15% and the mean number of bacteria per cell was < 4. Binding of H. pylori to epithelial cells could be partly blocked by pre-incubation with polyclonal anti-sera or using oligosaccharides against potential binding epitopes of gastric mucus. Fluorescent labelling of H. pylori with CFDA-SE in combination with flow cytometry provides a quick, specific, and sensitive method to quantitate in vitro the adherence of H. pylori.


Assuntos
Aderência Bacteriana , Citometria de Fluxo/métodos , Helicobacter pylori/metabolismo , Estômago/microbiologia , Anticorpos Antibacterianos/imunologia , Linhagem Celular , Células Epiteliais/microbiologia , Fluoresceínas , Corantes Fluorescentes , Helicobacter pylori/imunologia , Humanos , Reprodutibilidade dos Testes , Estômago/citologia , Succinimidas
14.
Glycoconj J ; 15(5): 469-75, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9881748

RESUMO

Many studies have reported changes in the carbohydrate structure of serum glycoproteins in disease, but this information is often of limited value for understanding disease mechanisms because it is obtained with simple and/or indirect methodologies that determine only one structural feature. On the other hand, more detailed carbohydrate methodologies are time-consuming and require a lot of purified material. Using haptoglobin (Hp) as a model protein, a new procedure was devised that determined the oligosaccharide composition of very small amounts of Hp in a relatively short time. The Hp was purified by batch affinity-chromatography, oligosaccharides were removed with PNGase F, and the oligosaccharide composition of charged species was determined using HPAEC/PAD (Dionex carbohydrate analyser). The method was applied to the analysis of Hp from eight healthy individuals and 37 patients with different inflammatory diseases or cancers. Twenty-seven oligosaccharides were consistently detected, but the majority could not be identified. However, by calculating retention times relative to the sialylated biantennary peak (Neu5Ac(alpha)2-3/6Gal(beta)1-4GlcNAc(beta)1-2Man(alpha)1-6(Neu 5Ac(alpha)2-3/6Gal(beta)1-4GlcNAc(beta)1-2Man(alpha)1-3)Man(beta)1-4G lcNAc(beta)1-4GlcNAc) it was possible to compare profiles quantitatively. Although no peak was identified as disease-specific, characteristic and reproducible profiles were obtained. Particularly striking were reductions in the major peaks in Crohn's disease, rheumatoid arthritis, stomach cancer, accompanied by increases in unidentified peaks. Previous studies suggested that many of the unknown peaks were due to increased sialylation and fucosylation. Only small changes in patterns were observed for breast and ovarian cancer. The new procedure will be very useful in the characterization of oligosaccharide composition of glycoproteins in clinical specimens.


Assuntos
Amidoidrolases/metabolismo , Haptoglobinas/metabolismo , Oligossacarídeos/metabolismo , Polissacarídeos/metabolismo , Adulto , Idoso , Artrite Reumatoide/sangue , Cromatografia Líquida de Alta Pressão , Cromatografia por Troca Iônica , Doença de Crohn/sangue , Glicosilação , Haptoglobinas/química , Humanos , Pessoa de Meia-Idade , Neoplasias/sangue , Peptídeo-N4-(N-acetil-beta-glucosaminil) Asparagina Amidase , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
15.
Glycoconj J ; 15(12): 1149-54, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10372970

RESUMO

Both infiltrating leukocytes and soluble immunoglobulin form aggregates in synovial fluid during the inflammatory process in rheumatoid arthritis (RA). Some of these changes are probably mediated by the adhesion molecule, E-selectin, which increases its expression with disease activity. As glycosylation changes in IgG in RA are well established, the current study was undertaken to measure the expression of the carbohydrate antigen sialyl Lewis x (sLe(x)), on IgG in RA. sLe(x) is a major ligand for E-selectin. Using a recently developed ELISA, sLe(x) expression was determined in IgG isolated from 8 healthy individuals, 20 RA sufferers (10 early and 10 with more long-standing disease) and 20 patients with other rheumatic conditions (osteoarthritis, ankylosing spondylitis, systemic lupus erythematosus). S Le(x) expression on IgG was elevated above the reference range in all but one of the RA patients and this change was highly significant (P < 0.0006). Expression of this antigen on IgG was also significantly different from normal in the other arthritic groups (P < 0.02), but the changes were much less than that observed for RA. In early RA, sLe(x) was inversely correlated with parameters used to measure disease activity. This was not observed with the established RA, where there was weak positive association. These preliminary results indicate that a change in sLe(x) expression on IgG is an early finding in the development of RA, which may be important in the development of the disease or for predicting its outcome.


Assuntos
Artrite Reumatoide/imunologia , Imunoglobulina G/imunologia , Oligossacarídeos/imunologia , Doenças Reumáticas/imunologia , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Glicosilação , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/metabolismo , Masculino , Pessoa de Meia-Idade , Antígeno Sialil Lewis X
16.
Glycoconj J ; 14(5): 611-22, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9298694

RESUMO

CD44 is a major cell surface receptor for the glycosaminoglycan, hyaluronan (HA). CD44 binds HA specifically, although certain chondroitin-sulfate containing proteoglycans may also be recognized. CD44 binding of HA is regulated by the cells in which it is expressed. Thus, CD44 expression alone does not correlate with HA binding activity. CD44 is subject to a wide array of post-translational carbohydrate modifications, including N-linked, O-linked and glycosaminoglycan side chain additions. These modifications, which differ in different cell types and cell activation states, can have profound effects on HA binding function and are the main mechanism of regulating CD44 function that has been described to date. Some glycosaminoglycan modifications also affect ligand binding specificity, allowing CD44 to interact with proteins of the extracellular matrix, such as fibronectin and collagen, and to sequester heparin binding growth factors. It is not yet established whether the HA binding function of CD44 is responsible for its proposed involvement in inflammation. It has been shown, however, that CD44/HA interactions can mediate leukocyte rolling on endothelial and tissue substrates and that CD44-mediated recognition of HA can contribute to leukocyte activation. Changes in CD44 expression (mainly up-regulation, occasionally down-regulation, and frequently alteration in the pattern of isoforms expressed) are associated with a wide variety of cancers and the degree to which they spread; however, in other cancers, the CD44 pattern remains unchanged. Increased expression of CD44 is associated with increased binding to HA and increased metastatic potential in some experimental tumor systems; however, in other systems increased HA binding and metastatic potential are not correlated. CD44 may contribute to malignancy through changes in the regulation of HA recognition, the recognition of new ligands and/or other new biological functions of CD44 that remain to be discovered.


Assuntos
Receptores de Hialuronatos/fisiologia , Inflamação/fisiopatologia , Metástase Neoplásica/fisiopatologia , Neoplasias/fisiopatologia , Animais , Antígenos CD/fisiologia , Sulfatos de Condroitina/metabolismo , Variação Genética , Humanos , Ácido Hialurônico/metabolismo , Neoplasias/patologia , Proteoglicanas/química , Proteoglicanas/metabolismo
17.
Glycoconj J ; 14(5): 647-9, 1997 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9298699

RESUMO

Ovarian cancer has the highest mortality rate of any gynaecological malignancy. This is caused by metastatic deposits obstructing the intestinal tract. Very little is known about the molecules involved in the initial attachment of the metastatic tumour cells to the peritoneal mesothelial lining. Previously, we showed that many ovarian tumour lines express the adhesion molecule, CD44, on their cell surface. The major ligand for CD44 is the extracellular matrix glycosaminoglycan, hyaluronic acid (HA). Because mesothelial cells have a pericellular cost that contains large amounts of HA, it was postulated that the CD44/HA interaction is an important stage in ovarian cancer spread. However, it was difficult to demonstrate this interaction in an in vitro adhesion assay with mesothelial cells as most of the HA, and presumably the bound tumour cells, were lost from the mesothelial cells during the washing steps of the assay. In order to try and clarify the situation, the adhesion of six ovarian tumour lines to immobilized HA was measured. Four lines expressed high levels of CD44 and two lines expressed negligible amounts. Preliminary experiments were carried out with one of the CD44-expressing lines. After coating a plate overnight with 3 mg ml(-1) HA, the 5 min adhesion of this line varied between 2% and 73% according to the type of plate that was used. Falcon Micro Test III flexible plates gave the highest adhesion and was used for further experiments. Plates were coated with concentrations of HA between 0.001 mg ml(-1) and 3 mg ml(-1). All CD44 expressing lines adhered to HA, but the maximum adhesion and the adhesion strength varied with the line studied and was not closely related to the total CD44 expression. These results suggest that CD44 on ovarian tumour cells binds to HA on mesothelial cells. As much of the HA can be very easily lost from the mesothelial cell surface, additional factors such as the strength of the CD44/HA interaction, and the formation of bonds by the tumour cells with other membrane adhesion molecules, such as integrins, are also important in promoting tumour spread.


Assuntos
Antígenos CD/fisiologia , Células Imobilizadas/fisiologia , Receptores de Hialuronatos/fisiologia , Ácido Hialurônico/metabolismo , Neoplasias Ovarianas/fisiopatologia , Adesão Celular , Epitélio/fisiologia , Feminino , Humanos , Metástase Neoplásica , Neoplasias Ovarianas/patologia , Células Tumorais Cultivadas
19.
Glycoconj J ; 14(4): 457-65, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9249143

RESUMO

This study was performed in order to gain insight into the occurrence, glycosylation and the possible origin of the acute-phase proteins alpha1-acid glycoprotein (AGP) and alpha1-protease inhibitor (PI) in sera and synovial fluid from patients with rheumatoid arthritis (RA). Therefore paired sera and synovial fluid samples from patients with RA, and paired synovial fluid samples from right and left knees of patients with varying degrees of arthritis were studied. Crossed affinity immunoelectrophoresis (CAIE) was used with concanavalin A and Aleuria aurantia lectin for the detection of the degree of branching and fucosylation, respectively, and the monoclonal CSLEX-1 for the detection of Sialyl Lewis(X) (SLe(X)) groups on AGP. For PI, not only CAIE, but also high-pressure-anion-exchange chromatography with pulsed amperometric detection was used to study the glycosylation. It was established that the concentrations of AGP and PI were increased in the serum of RA patients compared to normal healthy controls, but that the concentration of both proteins, as well as albumin, was significantly lower in synovial fluid than in serum. Furthermore, the type of glycosylation of both AGP and PI found in RA was significantly different from that found in normals, with increased fucosylation, but there were no major differences in the degree of branching of AGP- or PI-glycans in RA, compared to normals. No differences in glycosylation could be established between serum and synovial fluid in RA. For PI an increased fucosylation was found, both in serum and synovial fluid, using both methods of detection, and it could be established that only the alpha1-->3- and not the alpha1-->6-fucosylation of PI was affected by RA. The increased fucosylation of AGP resulted in an increased expression of SLe(X) on AGP-glycans. Since the alpha1-->3-fucosylation of AGP was significantly increased in both serum and synovial fluid from RA patients, and this correlated with systemic but not with local disease parameters, it can be suggested that acute phase proteins in synovial fluid are most probably of hepatic origin.


Assuntos
Artrite Reumatoide/metabolismo , Orosomucoide/metabolismo , Líquido Sinovial/metabolismo , alfa 1-Antitripsina/metabolismo , Adulto , Idoso , Artrite Reumatoide/sangue , Artrite Reumatoide/tratamento farmacológico , Feminino , Glicosilação , Humanos , Masculino , Pessoa de Meia-Idade , Oligossacarídeos/metabolismo , Orosomucoide/imunologia , Antígeno Sialil Lewis X
20.
Glycoconj J ; 14(4): 493-6, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-9249148

RESUMO

To unravel the complexities of the glycosylation of a protein is a substantial task, which requires considerable effort and resources. However, in many situations this is unnecessary, because only a limited amount of information is required. A new lectin-binding assay is described which is rapid, cheap and versatile. A purified glycoprotein is absorbed on to the plastic surface of a microtitre plate. After removing unbound protein by washing, uncoated sites on the plate are blocked and digoxigenin or biotin-labelled lectin is added. The degree of lectin binding is measured using either an anti-DIG antibody or streptavidin conjugated enzyme, which is subsequently used to develop a colour reaction. Using this method it is possible to screen multiple specimens with high sensitivity and excellent precision. In addition, very small amounts of lectin are used, background absorbances are low, and the procedure does not require a high degree of technical skill. Because very small amounts of glycoprotein are needed, a glycoprotein can often be rapidly purified by batch affinity chromatography. The method has been successfully applied to several purified proteins using the lectins, Con A, LCA, LTA, MAA, and SNA, and the information obtained agrees with that produced by more sophisticated approaches, eg Dionex Carbohydrate Analyser. Using a panel of lectins, a carbohydrate structural profile is quickly built-up, and subtle differences in glycosylation identified. This method should be particularly useful for screening glycosylation in multiple clinical specimens; in specimens where very small amounts of material are available, such as membrane molecules; and in the screening of recombinant proteins produced commercially.


Assuntos
Ensaio de Imunoadsorção Enzimática/métodos , Glicoproteínas/análise , Cromatografia de Afinidade , Glicoproteínas/isolamento & purificação , Glicosilação , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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