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1.
Mol Cell Biochem ; 427(1-2): 103-109, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27995412

RESUMO

We have previously demonstrated that the E3 ligase Human Constitutive Photomorphogenic Protein (huCOP1) is expressed in human keratinocytes and negatively regulates p53. The MutS homolog 2 (MSH2) protein plays a central role in DNA MMR mechanism and is implicated in the cellular response to anticancer agents, such as cisplatin. Our aim was to clarify whether huCOP1 plays a role in DNA MMR by affecting MSH2 protein level in human keratinocytes. To define the role of huCOP1 in DNA mismatch repair, we determined whether huCOP1 affects MSH2 abundance. MSH2 protein level was detected by immunocytochemical staining using a keratinocyte cell line in which the expression level of huCOP1 was stably decreased (siCOP1). To investigate whether huCOP1 silencing influences cisplatin-induced cell death, control and siCOP1 keratinocyte cells were treated with increasing concentrations of cisplatin and cell viability was recorded after 48 and 96 h. Stable silencing of huCOP1 in human keratinocytes resulted in a reduced level of MSH2 protein. huCOP1 silencing also sensitized keratinocytes to the interstrand crosslinking inducer cisplatin. Our results indicate that decreased huCOP1 correlates with lower MSH2 levels. These protein level changes lead to increased sensitivity toward cisplatin treatment, implicating that huCOP1 plays a positive role in maintaining genome integrity in human keratinocytes.


Assuntos
Reparo do DNA , Instabilidade Genômica/fisiologia , Queratinócitos/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Linhagem Celular Transformada , Cisplatino/farmacologia , Instabilidade Genômica/efeitos dos fármacos , Humanos , Proteína 2 Homóloga a MutS/metabolismo , Proteína Supressora de Tumor p53/metabolismo
3.
J Eur Acad Dermatol Venereol ; 29(12): 2333-41, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26370610

RESUMO

BACKGROUND: Glycerol is known to possess anti-irritant and hydrating properties and previous studies suggested that xylitol may also have similar effects. OBJECTIVE: Our aim was to study whether different concentrations of these polyols restore skin barrier function and soothe inflammation in sodium lauryl sulphate (SLS)-induced acute irritation. METHODS: The experiments were performed on male SKH-1 hairless mice. The skin of the dorsal region was exposed to SLS (5%) for 3 h alone or together with 5% or 10% of glycerol respectively. Further two groups received xylitol solutions (8.26% and 16.52% respectively) using the same osmolarities, which were equivalent to those of the glycerol treatments. The control group was treated with purified water. Transepidermal water loss (TEWL) and skin hydration were determined. Microcirculatory parameters of inflammation were observed by means of intravital videomicroscopy (IVM). Furthermore, accumulation of neutrophil granulocytes and lymphocytes, the expression of inflammatory cytokines and SLS penetration were assessed, as well. RESULTS: Treatment with the 10% of glycerol and both concentrations of xylitol inhibited the SLS-induced elevation of TEWL and moderated the irritant-induced increase in dermal blood flow and in the number of leucocyte-endothelial interactions. All concentrations of the applied polyols improved hydration and prevented the accumulation of lymphocytes near the treatment site. At the mRNA level, neither glycerol nor xylitol influenced the expression of interleukin-1 alpha. However, expression of interleukin-1 beta was significantly decreased by the 10% glycerol treatment, while expression of tumour necrosis factor-alpha decreased upon the same treatment, as well as in response to xylitol. Higher polyol treatments decreased the SLS penetration to the deeper layers of the stratum corneum. CONCLUSION: Both of the analysed polyols exert considerable anti-irritant and anti-inflammatory properties, but the effective concentration of xylitol is lower than that of glycerol.


Assuntos
Dermatite Irritante/tratamento farmacológico , Emolientes/uso terapêutico , Glicerol/uso terapêutico , Fenômenos Fisiológicos da Pele/efeitos dos fármacos , Pele/metabolismo , Xilitol/uso terapêutico , Animais , Dermatite Irritante/etiologia , Dermatite Irritante/patologia , Emolientes/farmacologia , Expressão Gênica/efeitos dos fármacos , Glicerol/farmacologia , Interleucina-1alfa/genética , Interleucina-1beta/genética , Microscopia Intravital , Masculino , Camundongos , Camundongos Pelados , Permeabilidade/efeitos dos fármacos , Fluxo Sanguíneo Regional/efeitos dos fármacos , Pele/irrigação sanguínea , Pele/química , Dodecilsulfato de Sódio/farmacocinética , Fator de Necrose Tumoral alfa/genética , Água/análise , Perda Insensível de Água/efeitos dos fármacos , Xilitol/farmacologia
5.
Histochem Cell Biol ; 138(4): 653-67, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22688676

RESUMO

The 180 kDa transmembrane collagen XVII is known to anchor undifferentiated keratinocytes to the basement membrane in hemidesmosomes while constitutively shedding a 120 kDa ectodomain. Inherited mutations or auto-antibodies targeting collagen XVII cause blistering skin disease. Collagen XVII is down-regulated in mature keratinocytes but re-expressed in skin cancer. By recently detecting collagen XVII in melanocyte hyperplasia, here we tested its expression in benign and malignant melanocytic tumors using endodomain and ectodomain selective antibodies. We found the full-length collagen XVII protein in proliferating tissue melanocytes, basal keratinocytes and squamous cell carcinoma whereas resting melanocytes were negative. Furthermore, the cell-residual 60 kDa endodomain was exclusively detected in 62/79 primary and 15/18 metastatic melanomas, 8/9 melanoma cell lines, HT199 metastatic melanoma xenografts and atypical nests in 8/63 dysplastic nevi. The rest of 19 nevi including common, blue and Spitz subtypes were also negative. In line with the defective ectodomain, sequencing of COL17A1 gene revealed aberrations in the ectodomain coding region including point mutations. Collagen XVII immunoreaction-stained spindle cell melanomas, showed partly overlapping profiles with those of S100B, Melan A and HMB45. It was concentrated at vertical melanoma fronts and statistically associated with invasive phenotype. Antibody targeting the extracellular aa507-529 terminus of collagen XVII endodomain promoted apoptosis and cell adhesion, while inhibiting proliferation in HT199 cells. These results suggest that the accumulation of collagen XVII endodomain in melanocytic tumors is associated with malignant transformation to be a potential marker of malignancy and a target for antibody-induced melanoma apoptosis.


Assuntos
Apoptose/fisiologia , Autoantígenos/genética , Autoantígenos/metabolismo , Regulação Neoplásica da Expressão Gênica , Queratinócitos/patologia , Melanócitos/metabolismo , Melanoma/metabolismo , Colágenos não Fibrilares/genética , Colágenos não Fibrilares/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticorpos/metabolismo , Western Blotting , Linhagem Celular Tumoral , Feminino , Humanos , Hiperplasia/metabolismo , Imuno-Histoquímica , Masculino , Melanócitos/citologia , Melanócitos/patologia , Melanoma/patologia , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Colágeno Tipo XVII
6.
Dis Esophagus ; 25(5): 395-402, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22035281

RESUMO

Specialized intestinal metaplasia (SIM) is considered as a premalignant condition of the esophagus, but other types of esophageal metaplasia are commonly neglected. A standardized histopathological analysis was focused not only on SIM but also on the presence of metaplastic processes typical of additional glands. A morphological study using standardized histopathological tests was carried out between 2004 and 2007, with biopsies taken from esophageal mucosa of 826 consecutive patients. Mean age and male : female ratio of patients were 55.6 ± 14.7 and 1.1 : 1, respectively. Only 4.1% (n = 34) of all cases proved to have SIM. The remainder of the cases (n = 615; 74.4%) contained cardiac-fundic mucosa without SIM. Some samples exhibited superficial mucous glands, pancreatic acinar metaplasia (PAM), and ciliated metaplasia accounting for 24% (n = 198), 14.9% (n = 123), and 0.2% (n = 2), respectively. SIM was colocalized with superficial mucous glands (103/198 superficial mucous gland cases; P < 0.001). Low-grade dysplasia (n = 51; 6.2%) and high-grade dysplasia (n = 9; 1.1%) were found mainly in SIM (37/51; 9/9; P = 0.071) with male preponderance (3 : 1 at low-grade and 2 : 1 at high-grade dysplasia). PAM was found mainly in cases without dysplasia (103 of 123 pancreatic metaplasias; P < 0.001). SIM alone in the esophagus is rare, and its frequent association with cardiac mucosa-type metaplasia testifies to transition of mucinous-goblet cell through pseudogoblet cells. PAM rather indicates absence of dysplasia, but superficial mucous glands predicts that SIM follows dysplasia.


Assuntos
Esôfago de Barrett/patologia , Esôfago/patologia , Mucosa/patologia , Lesões Pré-Cancerosas/patologia , Adulto , Idoso , Biópsia , Esofagoscopia , Feminino , Células Caliciformes/patologia , Humanos , Masculino , Metaplasia , Pessoa de Meia-Idade
7.
Dis Esophagus ; 25(6): 498-504, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22107367

RESUMO

Although the pathogenesis of cervical inlet patch (CIP) is not fully understood, most authors consider it as a congenital abnormality, whereas others surmise it to be related to gastroesophageal reflux disease (GERD). We aimed to evaluate esophageal function and the prevalence of GERD and Barrett's esophagus in patients with CIP. GERD is defined by the presence of erosive esophagitis or an abnormal pH monitoring. Seventy-one consecutive patients with endoscopic and histological evidence of CIP were prospectively evaluated. Esophageal symptom analysis, 24-hour simultaneous biliary reflux and double-channel pH-monitoring, and esophageal manometry were carried out in 65/71 (92%) patients and in 25 matched controls. Six patients were not suitable for testing and were, therefore, excluded. The histological evaluation of the heterotopic islands showed cardia and/or oxyntic mucosa in 64/65 (98%) patients and specialized intestinal metaplasia (SIM) in one patient (2%). The cardia and/or oxyntic mucosa was accompanied by focally appearing pancreatic acinar metaplasia and pancreatic ductal metaplasia in 7/64 (11%) and in 1/64 (2%), superficial mucous glands in 6/64 (9%), and SIM in 2/64 (3%) cases. In total, SIM was present in three patients (5%), and one of them had low-grade dysplasia. At the gastroesophageal junction, 28 (43%) patients had columnar metaplasia, including nine (14%) patients with SIM. Erosive esophagitis was present in 37 (57%) cases. Thirty-two patients (49%) had abnormal acid reflux in the distal and 25 (38%) in the proximal esophagus. Abnormal biliary reflux was present in 25 (38%) cases. On the basis of endoscopic and pH studies, GERD was established in 44/65 (68%) patients. Typical reflux symptoms were common (33/65, 51%). The combined 24-hour biliary and double-channel pH-monitoring detected significantly more significant acidic reflux at both measurement points and significantly longer bile exposure time in the distal esophagus in patients with CIP. Acid secretion in the CIP was detected in three (5%) cases. Esophageal manometry revealed decreased LES pressure and prolonged relaxation with decreased peristaltic wave amplitude, and an increased number of simultaneous contractions in the esophageal body. The detailed evaluation of the esophageal morphology and function in subjects with CIP showed a high prevalence of GERD and Barrett's esophagus. Further studies are needed to evaluate whether combined acidic and biliary reflux is able to promote similar histomorphological changes in the CIP, as it is shown distally in patients with Barrett's esophagus.


Assuntos
Esôfago de Barrett/epidemiologia , Coristoma/epidemiologia , Doenças do Esôfago/epidemiologia , Mucosa Gástrica , Refluxo Gastroesofágico/epidemiologia , Adulto , Idoso , Esôfago de Barrett/patologia , Refluxo Biliar/epidemiologia , Refluxo Biliar/patologia , Estudos de Casos e Controles , Coristoma/patologia , Comorbidade , Doenças do Esôfago/patologia , Esfíncter Esofágico Inferior/fisiopatologia , Monitoramento do pH Esofágico , Junção Esofagogástrica/patologia , Esofagoscopia , Feminino , Refluxo Gastroesofágico/patologia , Humanos , Masculino , Manometria , Metaplasia/patologia , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos
8.
G Ital Dermatol Venereol ; 146(1): 53-6, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21317857

RESUMO

AIM: In order to map the frequency of contact hypersensitivity (CH) to epoxy resin, methyldibromoglutaronitrile (MDBGN), tixocortol pivalate (TP) and budesonide patch tests were carried out. METHODS: The tests were performed in 1448 patients. Most patients belong to the allergic and irritative contact dermatitis groups. The tests were administered with the allergens epoxy resin 1%, MDBGN 0.3%, TP 1% and budesonide 0.1%, applied on the back. Reactions were evaluated at 40 min, on day 2 (D2), day 3 (D3) and day 4 (D4). In the patients of the Dept. of Dermatology, Venerology and Dermatooncology of Semmelweis University (patients number =1073) reactions were evaluated on day 7 as well. RESULTS: Epoxy resin elicited immediate reactions in 1 patient at 40 min. Further evaluations showed no difference on D3, D4 and D7 with a frequency of CH of 1.03%. Patch testing for MDBGN did not provoke immediate reactions, evaluations showed an increasing hypersensitivity rate (D2: 0.93%; D7:1.77%). Patch tests with TP yielded no immediate reactions, the frequency of CH increased from 0.47% (D2) to 2.01% (D7). No immediate reactions were observed by budesonide; an increase was seen in frequency of CH (D2:0.93% to D7:3.84%). CH to the studied allergens was observed mostly in allergic contact dermatitis group, to budesonide in irritative contact dermatitis and in atopic dermatitis groups as well. CONCLUSION: The data of the present study are the first results about this four allergens in Hungary and to our knowledge from our region as well.


Assuntos
Budesonida/efeitos adversos , Dermatite de Contato/epidemiologia , Resinas Epóxi/efeitos adversos , Hidrocortisona/análogos & derivados , Nitrilas/efeitos adversos , Alérgenos , Dermatite Alérgica de Contato/diagnóstico , Dermatite Alérgica de Contato/epidemiologia , Dermatite Alérgica de Contato/etiologia , Dermatite de Contato/diagnóstico , Dermatite de Contato/etiologia , Dermatite Irritante/diagnóstico , Dermatite Irritante/epidemiologia , Dermatite Irritante/etiologia , Humanos , Hungria/epidemiologia , Hidrocortisona/efeitos adversos , Hipersensibilidade Imediata/diagnóstico , Hipersensibilidade Imediata/epidemiologia , Hipersensibilidade Imediata/etiologia , Testes do Emplastro , Conservantes Farmacêuticos/efeitos adversos , Urticária/diagnóstico , Urticária/epidemiologia , Urticária/etiologia
9.
Pathol Oncol Res ; 26(3): 1861-1868, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31792874

RESUMO

Sentinel lymph node biopsy (SLNB) is a standard procedure for regional lymph node staging and still has the most important prognostic value for the outcome of patients with thin melanoma. In addition to ulceration, SLNB had to be considered even for a single mitotic figure in thin (<1 mm) melanoma according to AJCC7th guideline, therefore, a retrospective review was conducted involving 403 pT1 melanoma patients. Among them, 152 patients suffered from pT1b ulcerated or mitotic rate ≥ 1/ mm2 melanomas according to the AJCC7th staging system. SLNB was performed in 78 cases, of which nine (11.5%) showed SLN positivity. From them, interestingly, we found a relatively high positive sentinel rate (6/78-8%) in the case of thin primary melanomas ˂0.8 mm. Moreover, the presence of regression increased the probability of sentinel positivity by 5.796 fold. After reassessing pT stage based on the new AJCC8th, 37 pT1b cases were reordered into pT1a category. There was no significant relation between other characteristics examined (age, gender, Breslow, Clark level, and mitosis index) and sentinel node positivity. Based on our data, we suggest that mitotic rate alone is not a sufficiently powerful predictor of SLN status in thin melanomas. If strict histopathological definition criteria are applied, regression might be an additional adverse feature that aids in identifying T1 patients most likely to be SLN-positive. After reassessing of pT1b cases according to AJCC8th regression proved to be independent prognostic factor on sentinel lymph node positivity. Our results propose that sentinel lymph node biopsy might also be considered at patients with regressive thin (˂0.8 mm) melanomas.


Assuntos
Melanoma/diagnóstico , Melanoma/patologia , Biópsia de Linfonodo Sentinela/métodos , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/patologia , Adulto , Idoso , Feminino , Humanos , Metástase Linfática/diagnóstico , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Índice Mitótico , Estadiamento de Neoplasias/métodos , Estudos Retrospectivos , Adulto Jovem , Melanoma Maligno Cutâneo
10.
J Eur Acad Dermatol Venereol ; 23(2): 124-8, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18761544

RESUMO

BACKGROUND: Periocular contact dermatitis may appear as contact conjunctivitis, contact allergic and/or irritative eyelid and periorbital dermatitis, or a combination of these symptoms. The clinical symptoms may be induced by several environmental and therapeutic contact allergens. OBJECTIVES: The aim of the present study was to map the eliciting contact allergens in 401 patients with periocular dermatitis (PD) by patch testing with environmental and ophthalmic contact allergens. METHODS: Following the methodics of international requirements, 401 patients were tested with contact allergens of the standard environmental series, 133 of 401 patients with the Brial ophthalmic basic and supplementary series as well. RESULTS: Contact hypersensitivity was detected in 34.4% of the patients. Highest prevalence was seen in cases of PD without other symptoms (51.18%), in patients of PD associated with ophthalmic complaints (OC; 30.4%), and PD associated with atopic dermatitis (AD; 27.9%). In the subgroup of PD associated with seborrhoea (S) and rosacea (R), contact hypersensitivity was confirmed in 17.6%. Most frequent sensitisers were nickel sulphate (in 8.9% of the tested 401 patients), fragrance mix I (4.5%), balsam of Peru (4.0%), paraphenylendiamine (PPD) (3.7%), and thiomersal (3.5%). By testing ophthalmic allergens, contact hypersensitivity was observed in nine patients (6.7% of the tested 133 patients). The most common confirmed ophthalmic allergens were cocamidopropyl betaine, idoxuridine, phenylephrine hydrochloride, Na chromoglycinate, and papaine. LIMITATIONS: Patients with symptoms of PD were tested from 1996 to 2006. CONCLUSIONS: The occurence of contact hypersensitivity in PD patients was in present study 34.4%. A relatively high occurrence was seen in cases of PD without other symptoms, in PD + OC and in PD + AD patients. The predominance of environmental contact allergens was remarkable: most frequent sensitizers were nickel sulphate, fragrance mix I, balsam of Peru, thiomersal, and PPD. The prevalence of contact hypersensitivity to ophthalmic allergens did not exceed l.5%.


Assuntos
Dermatite de Contato/diagnóstico , Dermatite Perioral/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alérgenos/efeitos adversos , Criança , Cosméticos/efeitos adversos , Dermatite de Contato/etiologia , Dermatite Perioral/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes do Emplastro
11.
J Eur Acad Dermatol Venereol ; 22(11): 1346-55, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18680530

RESUMO

BACKGROUND: Atopic dermatitis (AD) is a clinically well-defined, chronic-intermittant, genetically predisposed skin disease. The increasing number of adult cases observed in the last years has turned the attention to ascertaining factors eliciting skin symptoms. Studies have revealed numerous environmental components (e.g. contact and aeroallergens) that may play an important role in sustaining the symptoms. The aim of the study was to search for contact allergens and aeroallergens triggering the skin disease in adult AD patients. METHODS: Patients over 18 years from our Atopy Outpatient Department were included in the study. Diagnosis of AD was based on the clinical criteria of Hanifin and Rajka. The distribution of skin symptoms was characteristic for adult AD: hands, shoulders, neck, flexures, face and eyelids. The extremities and the trunk were less involved. The potentially provoking contact and aeroallergens were examined in symptom and drug-free period with atopy patch and epicutaneous tests (APT, ET), which were supplemented by in vitro allergy and Prick tests. The relevance of sensibilization was evaluated by the comparison of in vivo and in vitro test results, medical history and skin symptoms. RESULTS: A total number of 34 cases of adult AD (23 women and 11 men) were studied. Four of them were classified into the intrinsic group (IG; 12%), and 30 were classified into the extrinsic group (EG; 88%). The incidence of contact sensitization to environmental allergens was remarkable: 13 of the EG, 1 of the IG (14 of 34, 41%). In the IG, a late thiomersal positivity was detected without clinical relevance. In the EG, epicutaneous standard series late positivity was seen in 13 patients, in four of them with multiple sensitivity. The allergens causing positivity were nickel (6 of 13), thiomersal (3 of 13), mercury-amidochlorate (3 of 13), mercury-chloride (2 of 13), iodine chlorhyrdoxyquin (1 of 13), lanalcolum (1 of 13) and fragrance mix (1 of 13). Among the detected allergens, the following were relevant: lanalcolum (1 of 13: cosmetics), fragrance mix (1 of 13: cosmetics), nickel (1 of 13: metal objects), thiomersal (1 of 13: eyedrops). No immediate response was seen with APT. Relevant late positivity was shown with APT test in one patient in the IG (1 of 4) to Dermatophagoides pteronyssinus. We observed late positivity in 18 patients in the EG (18 of 30). Among the detected allergens, the following were clinically relevant: D. pteronyssinus and/or Dermatophagoides farinae (15 of 18), cat epithel (4 of 18), timothy pollen (1 of 18) and dog epithel (1 of 18). Furthermore, we examined the relevance of APT, specific immunoglobulin E (IgE) tests and Prick tests. We observed multiplex positivity by specific IgE tests, APT and Prick tests in 14 patients in EG. Sensitization to D. pteronyssinus and/or D. farinae (11 of 14) cat epithel (4 of 14), dog epithel (1 of 14) and timothy pollen (1 of 14) proved to be clinically relevant with the atopic skin symptoms and medical history. CONCLUSION: The proportion of contact sensitization to environmental allergens in the 34 adult atopic patients was remarkable (14 of 34, 41%). Out of the verified contact allergens, nickel, fragrance mix, thiomersal and lanalcolum proved to be relevant. House dust mite and cat epithel proved to be the most common relevant aeroallergens. D. pteronyssinus and D. farinae sensibilization was high, particularly in patients with severe skin symptoms on the face, eyelids and hands. Pollens should be considered in patients with seasonal relapse of AD. Sensitization to animal epithel was usually indicated by the flare-up of skin symptoms upon contact with animals. The relevance of the eliciting effects of sensitization could easily be supported in most cases by the medical history and the distribution of skin symptoms. In some adult AD patients with long-lasting AD, the relevance of triggering factors is hard to determine.


Assuntos
Alérgenos/imunologia , Dermatite Atópica/imunologia , Adolescente , Adulto , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Cutâneos
13.
Free Radic Biol Med ; 16(3): 347-53, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-8063198

RESUMO

Oxygen toxicity is thought to play an important pathogenic role in several neonatal diseases, including idiopathic respiratory distress syndrome (IRDS). Therefore, the development of a reliable measure of the actual oxidative stress status of patients would be of great clinical significance. In order to obtain information about the oxidative stress during the first week of life in premature infants with IRDS, the blood concentrations of oxidized and reduced glutathione, as well as their molar ratios, were determined by a highly sensitive, specific enzymic assay. The fractional inspired oxygen concentrations needed to maintain adequate arterial oxygen tension and the arterio-alveolar oxygen ratios were chosen as parameters indicating the severity of illness in premature infants at a given time. There was a highly significant positive correlation between the glutathione redox ratios and the fractional inspired oxygen concentrations. A maturity-related difference was also found; the oxidized glutathione concentrations were the highest in the least mature infants, accompanied by a pronounced compensatory rise in the reduced glutathione concentrations as well. A significant negative correlation was found between the arterio-alveolar oxygen ratio and the glutathione redox ratio: i.e., an improvement in oxygenation was accompanied by a decrease in the glutathione redox ratio. The efficient recycling of reduced glutathione in erythrocytes providing antioxidant protection for premature infants, permits the use of the blood glutathione redox ratio as a noninvasive measure of in vivo oxidative stress.


Assuntos
Glutationa/sangue , Síndrome do Desconforto Respiratório do Recém-Nascido/sangue , Antioxidantes/metabolismo , Radicais Livres , Glutationa/análogos & derivados , Dissulfeto de Glutationa , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Oxirredução , Oxigênio/sangue , Espécies Reativas de Oxigênio/metabolismo , Estresse Fisiológico/sangue
14.
Free Radic Biol Med ; 30(7): 715-21, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11275471

RESUMO

Gestational hypertension during the third trimester reflects an exaggerated maternal inflammatory response to pregnancy. We hypothesized that oxidative stress present even in normal pregnancy becomes uncompensated in hypertensive patients. A glucose-6-phosphate dehydrogenase (G6PD) activity sufficient to meet the increased reductive equivalent need of the cells is indispensable for defense against oxidative stress. The erythrocyte glutathione redox system was studied, where G6PD is the only NADPH source. The glutathione (GSH) redox status was measured both in vivo and after an in vitro oxidative challenge in pregnant women with gestational hypertension (n = 19) vs. normotensive pregnant subjects (n = 18) and controls (n = 20). An erythrocyte GSH depletion with an increase in the oxidized form (GSSG) resulted in an elevated ratio GSSG/GSH (0.305 +/- 0.057; mean +/- SD) in hypertensive pregnant women vs. normotensive pregnant or control subjects (0.154 +/- 0.025; 0.168 +/- 0.073; p <.001). In hypertensive pregnant patients, a "GSH stability" decrease after an in vitro oxidative challenge suggested a reduced GSH recycling capacity resulting from an insufficient NADPH supply. The erythrocyte GSSG/GSH ratio may serve as an early and sensitive parameter of the oxidative imbalance and a relevant target for future clinical trials to control the effects of antioxidant treatment in women at increased risk of the pre-eclampsia syndrome.


Assuntos
Glutationa/sangue , Hipertensão/sangue , Complicações Cardiovasculares na Gravidez/sangue , Adulto , Ceruloplasmina/metabolismo , Eritrócitos/metabolismo , Feminino , Glucosefosfato Desidrogenase/sangue , Humanos , NADP/metabolismo , Oxirredução , Estresse Oxidativo , Gravidez
15.
Free Radic Biol Med ; 27(7-8): 738-43, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10515577

RESUMO

This study examines the glutathione status of red blood cells in patients with retinopathy of prematurity (ROP) both in vivo and after an in vitro oxidative challenge. Fifty ROP patients of different ages (between 6 weeks and 6 years), born prematurely (gestational age: 28.7 +/- 1.3 weeks; birth weight: 1210 +/- 313 g; mean +/- SD) suffering either from active ROP (<3 months old; n = 12) or from a visual handicap due to preceding ROP (3 months-6 years; n = 38) as well as control patients of similar age and maturity (n = 56) were included. Infants with active disease have the lowest levels of reduced glutathione (GSH), the highest levels of oxidized form (GSSG), the highest GSSG/GSH ratios and the greatest fall in GSH after an in vitro oxidative challenge. After an in vitro oxidative stress, defective glutathione recycling was found in patients with preceding ROP and was suggested as a factor predisposing to oxidative hemolysis. The glutathione redox ratio was warranted as a biochemical screen for active ROP in premature infants.


Assuntos
Eritrócitos/metabolismo , Glutationa/sangue , Retinopatia da Prematuridade/sangue , Criança , Pré-Escolar , Feminino , Idade Gestacional , Dissulfeto de Glutationa/sangue , Hemólise , Humanos , Lactente , Recém-Nascido , Masculino , Metemoglobina/metabolismo , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Retinopatia da Prematuridade/diagnóstico
16.
Free Radic Biol Med ; 22(1-2): 161-8, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-8958140

RESUMO

The changes in red blood cell (RBC) lipid peroxidation [measured via the malonyl dialdehyde (MDA) concentration], reduced (GSH), and oxidized glutathione (GSSG) levels, hemoglobin (Hb) oxidation and antioxidant enzyme [catalase (Cat), glutathione peroxidase, and superoxide dismutase (SOD)] activities were studied in 45 pediatric patients with various glomerular diseases [minimal change nephrotic syndrome (MCNS) in relapse or in remission, lupus nephropathy (SLE), poststreptococcal glomerulonephritis (APSGN), IgA nephropathy (IGA gn)], and in 20 adult patients with IGA gn and also in 15 pediatric and 14 adult controls. The in vitro effects of hydrogen peroxide [acetyl phenylhydrazine (APH) test] on the GSH and Hb metabolisms were likewise investigated. There was an increased oxidative stress in MCNS with relapse, IGA gn, SLE gn, and APSGN, which could be detected in the GSH and Hb oxidation and in the lipid peroxidation on the peripheral RBC-s. The RBC SOD and Cat activities were significantly lower in all patients than in the controls. The RBC GSSG level was significantly elevated in all patients, with the exception of MCNS in remission. This stimulated a compensatory GSH production in MCNS with relapse and in IGA gn, but not in SLE or APSGN. The regeneration of GSH from GSSG was reduced in MCNS with relapse, SLE, and IGA gn, but not in APSGN. In remission, the GSH-GSSG redox system normalizes, but in vitro the APH test stimulates an intensive Hb oxidation. In conclusion, there is a correlation between the presence of active glomerular disease and the evidence of oxidative changes in the various parameters measured in peripheral RBCs.


Assuntos
Antioxidantes/metabolismo , Eritrócitos/metabolismo , Glomerulonefrite/fisiopatologia , Peroxidação de Lipídeos/fisiologia , Nefrose Lipoide/fisiopatologia , Estresse Oxidativo/fisiologia , Adolescente , Adulto , Estudos de Casos e Controles , Catalase/sangue , Criança , Pré-Escolar , Eritrócitos/enzimologia , Feminino , Glomerulonefrite/sangue , Glutationa/análogos & derivados , Glutationa/sangue , Dissulfeto de Glutationa , Glutationa Peroxidase/sangue , Hemoglobinas/metabolismo , Humanos , Masculino , Malondialdeído/sangue , Pessoa de Meia-Idade , Nefrose Lipoide/sangue , Superóxido Dismutase/sangue
17.
Intensive Care Med ; 27(1): 216-21, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11280638

RESUMO

OBJECTIVES: The possible role of xanthine oxidase (XO) activation in the signal transduction process during the septic shock syndrome was examined. The XO activity index after caffeine intake was assessed simultaneously with the blood glutathione redox ratio, a known parameter of oxidative stress. DESIGN AND SETTING: An investigational clinical study in a nine-bed pediatric intensive care unit. PATIENTS: Critically ill infants and children (n = 34) with systemic inflammatory response syndrome following infection, trauma or major surgery. Biochemical investigations (n = 54) were performed at various stages of the shock syndrome, characterized by pediatric risk of mortality and organ dysmetabolic scores. Controls consisted of 30 healthy children. MEASUREMENTS AND RESULTS: The in vivo XO activity index was measured as the urinary ratio of two metabolites of caffeine: 1-methyluric acid and 1-methylxanthine. The blood concentrations of oxidized (GSSG) and reduced glutathione (GSH) were determined. The XO activity index and redox ratio GSSG/GSH were highly increased in patients in shock dominated by the clinical symptoms of a proinflammatory response. A significantly lower XO activity index was found with an increased GSSG/ GSH in patients whose stage of shock was characteristic of an excessive anti-inflammatory response. The XO activity index and GSSG/ GSH were correlated closely with each other (r = 0.624, n = 54; p < 0.001), and were also related to the daily severity scores. CONCLUSION: Potent and simultaneous activation of the two redox systems strongly indicates a definite role of free radicals from XO in the overspill of the acute proinflammatory reaction of the shock syndrome, followed by a significant downregulation.


Assuntos
Glutationa/sangue , Estresse Oxidativo , Síndrome de Resposta Inflamatória Sistêmica/metabolismo , Xantina Oxidase/urina , Biomarcadores , Estudos de Casos e Controles , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Insuficiência de Múltiplos Órgãos/metabolismo , Oxirredução , Estatísticas não Paramétricas
18.
Artigo em Inglês | MEDLINE | ID: mdl-10883060

RESUMO

The roles of platelet function, plasma lipids and nitric oxide (NO) were studied in adolescent patients with essential hypertension (JEHT group), with chronic renal failure (CRF) associated with hypertension (CRFH group), and CRF patients with normal blood pressure (CRF group), as compared with normal controls (cont. group). Platelet aggregation and the thromboxane B(2)(TxB(2)) level were significantly higher in the JEHT and CRFH groups as compared with the cont. group, whereas they were significantly lower in the CRF group. On the other hand, the platelet cAMP level was significantly lower in the JEHT and CRFH groups than in the cont. group. The plasma NO level was significantly higher only in the JEHT as compared with the cont. group (120 +/- 39 and 89 +/- 21 microM, respectively). The plasma total cholesterol, triglyceride and LDL cholesterol concentrations were normal in the JEHT group, but high in the CRF and CRFH group, the HDL cholesterol level was lower in the CRF and CRFH groups as compared with the cont. and JEHT groups. There was a positive correlation between the platelet aggregation and the TxB(2)level and between the BP and the platelet aggregation. In conclusion, hyperlipidaemia is commonly present in uraemia with haemodialysis, but is not specific for hypertension in children, while an increased platelet function is frequently associated with hypertension. The increased NO level might play a compensatory role in JEHT.


Assuntos
Hipertensão/sangue , Lipídeos/fisiologia , Óxido Nítrico/fisiologia , Agregação Plaquetária/fisiologia , Tromboxano B2/fisiologia , Adolescente , Pressão Sanguínea , Criança , AMP Cíclico/sangue , Diálise , Feminino , Humanos , Hiperlipidemias/complicações , Hiperlipidemias/fisiopatologia , Hipertensão/etiologia , Lipídeos/sangue , Lipoproteínas/sangue , Masculino , Óxido Nítrico/sangue , Insuficiência Renal/sangue , Tromboxano B2/sangue
19.
J Neurol ; 246(7): 533-9, 1999 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10463352

RESUMO

Free radical action has been suggested as a causal factor in multiple sclerosis. We investigated the plasma level of lipid peroxides expressed in terms of malone dialdehyde and changes in blood nonenzymatic antioxidants (glutathione, alpha-tocopherol, retinol, plasma sulfhydryl groups, and uric acid) in multiple sclerosis patients with exacerbation or in remission, including a group treated with beta-interferon. The malone dialdehyde level was increased by 38% (n.s.) during exacerbations. The blood concentration of oxidized glutathione was likewise elevated (P<0.05), while the ratio of plasma alpha-tocopherol to cholesterol plus triglyceride was decreased (P<0.001). These changes suggest increased free radical production and consumption of the scavenger molecules during the active phase of the disease. Blood reduced glutathione level was increased (P<0.01) during exacerbation and remission as well. The rise in this thiol is likely to be a compensatory mechanism defending the cells from further oxidant injuries. Beta-interferon increased plasma alpha-tocopherol levels (P<0.001) but not the lipid corrected alpha-tocopherol value. Other parameters were not influenced by the drug.


Assuntos
Antioxidantes/análise , Malondialdeído/sangue , Esclerose Múltipla/sangue , Adulto , Antioxidantes/farmacologia , Feminino , Radicais Livres , Glutationa/sangue , Humanos , Interferon beta/uso terapêutico , Peróxidos Lipídicos/sangue , Masculino , Pessoa de Meia-Idade
20.
Free Radic Res ; 35(5): 555-61, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11767413

RESUMO

In the neonatal period, there is a high iron load, while both the level and molar oxidase activity of ceruloplasmin are low. On the other hand, the neonatal xanthine oxidase (XO) activity is higher than later in life and XO has a significant iron-oxidizing capacity. We therefore studied the physiological contribution of XO to the ferroxidase activity of the plasma in 20 full-term newborn infants. Ferroxidase activity was measured spectrophotometrically, with Fe++ as substrate. The uric acid formed by XO was assayed by means of HPLC, with electrochemical detection. The total ferroxidase activity in the plasma was about one-fourth of the adult level and rapidly increased doubling within 3 days after birth. About 90% of the plasma ferroxidase activity was due to ceruloplasmin, the remainder being accounted for by ferroxidase II. The XO activity underwent a 30% (statistically non-significant) elevation at 24 h, though ferroxidase activity attributable to XO was not detected at any time. Accordingly, XO does not seem to add substantially to the total iron-oxidizing capacity of the plasma in the neonatal period. The high molar ferroxidase activity is probably of importance at the endothelial cell surface.


Assuntos
Ceruloplasmina/análise , Recém-Nascido/sangue , Xantina Oxidase/sangue , Adulto , Fatores Etários , Humanos , Pessoa de Meia-Idade , Oxirredutases/sangue , Valores de Referência
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