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1.
ChemSusChem ; 13(17): 4595-4604, 2020 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-32441817

RESUMO

Lignosulfonates are bulk-scale byproducts of industrial sulfite pulping. Their amphiphilic character plays a central role in their successful application in large-scale materials production. As an inherent feature of the chemical structure, this amphiphilic character poses a major analytical challenge. In this study, the amphiphilic behavior of an industrial lignosulfonate was investigated by hydrophobic interaction chromatography (HIC). This technique exploits hydrophobic regions present on the surface of lignosulfonates. Extensive characterization of the obtained fractions from preparative HIC, in terms of elemental composition, functional-group content, chemical structure, and molecular weight distribution, revealed a detailed picture of the chemical composition distribution. The charge-to-size ratio, that is, differences in the degree of sulfonation, was the dominant factor governing separation in HIC. A combination of HIC with size exclusion chromatography showed good orthogonality of separation and demonstrated the power of this 2 D liquid chromatography approach for an in-depth characterization, in general, and amphiphilicity, in particular.

2.
Cerebellum ; 19(3): 437-445, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32170655

RESUMO

Dysphagia is a common symptom in neurodegenerative disorders and is generally associated with increased mortality. In the clinical care setting of ataxia patients, no systematical and standardized assessment of dysphagia is employed. Its impact on patients' health-related quality of life is not well understood. To assess the impact of dysphagia in ataxia patients on diet, body weight, and health-related quality of life. We conducted a large survey using self-reported questionnaires for swallowing-related quality of life (Swal-QOL) and a food frequency list in combination with retrospective clinical data of 119 patients with cerebellar ataxia treated in the neurological outpatient clinic of a large German university hospital. Seventeen percent of ataxia patients suffered from dysphagia based on the Swal-QOL score. Less than 1% of all patients reported dysphagia as one of their most disabling symptoms. Dysphagia was associated with unintentional weight loss (p = 0.02) and reduced health-related quality of life (p = 0.01) but did not affect individual nutritional habits (p > 0.05; Chi-squared test). Dysphagia is a relevant symptom in cerebellar ataxia. A systematic screening for dysphagia in patients with cerebellar ataxia would be desirable to enable early diagnosis and treatment.


Assuntos
Ataxia Cerebelar/fisiopatologia , Ataxia Cerebelar/psicologia , Transtornos de Deglutição/fisiopatologia , Transtornos de Deglutição/psicologia , Qualidade de Vida/psicologia , Inquéritos e Questionários , Adulto , Idoso , Idoso de 80 Anos ou mais , Ataxia Cerebelar/diagnóstico , Estudos Transversais , Deglutição/fisiologia , Transtornos de Deglutição/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
3.
Nutr Metab Cardiovasc Dis ; 27(10): 858-864, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28958691

RESUMO

BACKGROUND & AIMS: 3-Hydroxyisobutyrate (3-HIB), a catabolic intermediate of the BCAA valine, which stimulates muscle fatty acid uptake, has been implicated in the pathogenesis of insulin resistance. We tested the hypothesis that circulating 3-HIB herald insulin resistance and that metabolic improvement with weight loss are related to changes in BCAAs and 3-HIB. METHODS AND RESULTS: We analyzed plasma and urine in 109 overweight to obese individuals before and after six months on hypocaloric diets reduced in either carbohydrates or fat. We calculated the homeostasis model assessment index (HOMA-IR) and whole body insulin sensitivity from oral glucose tolerance tests and measured intramyocellular fat by magnetic resonance spectroscopy. BCAAs and 3-HIB plasma concentrations were inversely related to insulin sensitivity but not to intramyocellular fat content at baseline. With 7.4 ± 4.5% weight loss mean BCAA and 3-HIB plasma concentrations did not change, irrespective of dietary macronutrient content. Individual changes in 3-HIB with 6-month diet but not BCAAs were correlated to the change in whole body insulin sensitivity and HOMA-IR independently of BMI changes. CONCLUSIONS: 3-HIB relates to insulin sensitivity but is not associated with intramyocellular fat content in overweight to obese individuals. Moreover, changes in 3-HIB rather than changes in BCAAs are associated with metabolic improvements with weight loss. Registration number for clinical trials: ClinicalTrials.gov Identifier: NCT00956566.


Assuntos
Aminoácidos de Cadeia Ramificada/sangue , Restrição Calórica , Dieta com Restrição de Carboidratos , Dieta com Restrição de Gorduras , Hidroxibutiratos/sangue , Resistência à Insulina , Obesidade/dietoterapia , Redução de Peso , Tecido Adiposo/metabolismo , Adulto , Biomarcadores/sangue , Glicemia/metabolismo , Feminino , Teste de Tolerância a Glucose , Humanos , Insulina/sangue , Espectroscopia de Ressonância Magnética , Masculino , Metabolômica/métodos , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Obesidade/sangue , Obesidade/diagnóstico , Estudos Prospectivos , Fatores de Tempo , Resultado do Tratamento
4.
J Thromb Haemost ; 14(7): 1353-63, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27090446

RESUMO

UNLABELLED: Essentials Activated protein C (APC) resistance is a prevalent risk factor for venous thrombosis. A novel missense mutation (Ala512Val - FVBonn ) was characterized in vitro and in silico. FVBonn is a new cause of APC resistance and venous thrombosis. FVBonn expresses additionally enhanced procoagulant activity in the absence of APC. SUMMARY: Background Activated protein C (APC) resistance is a prevalent risk factor for venous thrombosis. This phenotype is most commonly associated with the factor V Arg506Gln mutation (FV Leiden), which impairs the APC-mediated inactivation of both activated FV (FVa) and activated FVIII (FVIIIa). Objectives Here, we report the identification and characterization of a novel FV mutation (Ala512Val, FVBonn ) in six patients with APC resistance and venous thrombosis or recurrent abortions. Methods FVBonn was expressed in a recombinant system and compared with recombinant wild-type (WT) FV and FV Leiden in several functional assays. Results FVBonn conferred APC resistance to FV-depleted plasma, both in the activated partial thromboplastin time (APTT)-based test (APC sensitivity ratio [APCsr] of 1.98 for FVBonn versus 4.31 for WT FV and 1.59 for FV Leiden) and in the thrombin generation-based test (normalized APCsr of 5.41 for FVBonn versus 1.00 for WT FV and 8.99 for FV Leiden). The APC-mediated inactivation of FVaBonn was slower than that of WT FVa (mainly because of delayed cleavage at Arg506), but was greatly stimulated by protein S. The APC cofactor activity of FVBonn in FVIIIa inactivation was ~ 24% lower than that of WT FV. In line with these findings, an in silico analysis showed that the Ala512Val mutation is located in the same loop as the Arg506 APC cleavage site and might hamper its interaction with APC. Moreover, FVBonn was more procoagulant than WT FV and FV Leiden in the absence of APC, because of an increased activation rate and, possibly, an enhanced interaction with activated FX. Conclusions FVBonn induces hypercoagulability via a combination of increased activation/procoagulant activity, decreased susceptibility to APC-mediated inactivation, and slightly reduced APC cofactor activity.


Assuntos
Resistência à Proteína C Ativada/genética , Fator V/genética , Mutação de Sentido Incorreto , Proteína C/genética , Aborto Habitual , Resistência à Proteína C Ativada/metabolismo , Adulto , Idoso , Coagulação Sanguínea/fisiologia , Testes de Coagulação Sanguínea , Catálise , Coagulantes/química , Estudos de Coortes , Fator V/metabolismo , Fator VIIIa/química , Fator Va/química , Feminino , Humanos , Masculino , Mutação , Tempo de Tromboplastina Parcial , Gravidez , Proteína C/metabolismo , Trombina/química , Tromboplastina/metabolismo , Trombose Venosa/genética , Trombose Venosa/metabolismo , Adulto Jovem
5.
Nervenarzt ; 84(5): 603-7, 2013 May.
Artigo em Alemão | MEDLINE | ID: mdl-23052889

RESUMO

BACKGROUND: Untreated psychiatric disorders of long-term unemployed persons represent a medical problem and a placement barrier to the labor market that can be eliminated. The objective of the study was to assess the spectrum of diagnoses and the treatment rates in a group of unemployed persons (≥ 50 years) referred by the employment exchange of the job center in Munich to a center for psychosocial coaching. METHODS: Out of 105 participants 44 (42%) showing signs of psychiatric disorders according to the patient health questionnaire (PHQ) screening were included in the evaluation. The psychiatric diagnoses were assessed by means of a fully structured diagnostic interview, the Munich composite international diagnostic interview (M-CIDI). A semi-structured interview was conducted to investigate the treatment rates and treatment compliance with guidelines. RESULTS: Affective disorders (70%) were in the foreground followed by anxiety disorders (55%, specific phobias, other and unspecified phobic anxiety disorders were excluded) and disorders due to abuse of alcohol (32%). Of the participants 61 % received no disorder-specific treatment or no treatment at all and treatment compliant with guidelines was received by 9%. CONCLUSIONS: Untreated psychiatric disorders (especially depression) or those that are not treated in compliance with guidelines represent a medical problem and a placement barrier to the labor market that can be eliminated.


Assuntos
Alcoolismo/epidemiologia , Alcoolismo/terapia , Transtornos Mentais/epidemiologia , Transtornos Mentais/terapia , Desemprego/estatística & dados numéricos , Adulto , Idoso , Comorbidade , Feminino , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco
6.
Clin Res Cardiol ; 100(4): 343-50, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21088843

RESUMO

AIM: To evaluate changes of right ventricular (RV) parameters in follow-up examinations after corrected tetralogy of Fallot (TOF) by cardiac magnetic resonance (CMR). METHODS: CMR was performed twice within 4 years in 45 patients using a 1.5 T scanner. RV-volumes and pulmonary-regurgitant-fractions (PRF) were calculated from standard cine-sequences and flow-sensitive gradient-echo images, respectively. Patients were divided into two groups depending on the post-operative (po) interval (group 1 ≤5 years po; group 2 >5 years po) and subgroups depending on type of surgery (transannular vs. non-transannular). Patient groups were compared among each other and differences between 1st and 2nd CMR were assessed. Furthermore, patients were compared with 25 healthy volunteers. RESULTS: Compared with controls RV-size was increased (group 1: p = 0.007; group 2: p < 0.001) and RV function decreased (group 1: p = 0.02; group 2: p < 0.001) in po TOF-patients. PRF was higher in group 2 compared with group 1 (p = 0.04) and significant changes of PRF between 1st and 2nd CMR were found in group 2 (p < 0.01), but not in group 1 (p = 0.29). Compared with the non-transannular subgroup, PRF (p < 0.001) and RV end-diastolic-volume index (RV-EDVI) (p = 0.03) were significantly higher in patients with a transannular patch, EDVI increased between 1st and 2nd CMR. After correction, no significant changes of RV myocardial mass index (RV-MMI) were found. CONCLUSION: After correction of TOF, RV-size, RV-muscle mass (RV-MM) was increased and ejection fraction decreased in "early" follow-up already. Whereas these parameters can remain stable over a long time period, the PRF significantly increased in "late" follow-up dependent on the po interval. Overall, transannular patching went along with higher PRF and bigger RV-size as well as a greater dynamic of these parameters in the time course, which makes this subgroup highly in need of regular follow-up examinations for the optimal timing of re-interventions. In contrast, the increased RV-MM demonstrated no regression po.


Assuntos
Tetralogia de Fallot/fisiopatologia , Tetralogia de Fallot/cirurgia , Função Ventricular Direita/fisiologia , Volume Cardíaco , Estudos de Casos e Controles , Criança , Feminino , Seguimentos , Ventrículos do Coração/fisiopatologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Insuficiência da Valva Pulmonar , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
7.
Arch Physiol Biochem ; 109(2): 180-90, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11780780

RESUMO

Isolation of glycosylated 26 kDa rat prolactin and subsequent proper carbohydrate characterization has so far not been reported. In the present work the hormone isoform was isolated to 95% homogeneity by preparative electrophoretic separation on Mini Prep Cell of rat pituitary homogenate. The isoform was then investigated by 2-mercaptoethanol gradient electrophoresis, Cleveland's sequential SDS-PAGE, digestion with endoproteinase Asp-N and N-glycanase. The glycosidic part of the isoform was examined in O-profiling and its monosaccharide composition obtained by FACE and HPAE-PAD analysis. The outcome of the experimental data is: 1) in contrast to unglycosylated 23 kDa rat prolactin, intra-chain S-S bridging is not affected in 26kDa rat prolactin, neither by transiting through a thiol gradient nor in sequential nonreducing/reducing SDS-PAGE; 2) the conformational availability of Asp residues involved in the endoproteinase Asp-N attack is the same in 23- and 26 kDa rat prolactin; the glycan moiety apparently does not cause steric hindrance at this level; 3) no glycosidic N-linkage could be detected, only O-linkage(s); 4) 26 kDa rat prolactin is no glycosyl-phosphaditylinositol-anchored protein; 5) in O-profiling an oligosaccharide chain of Mr +/- 1.4 kDa was recorded; 6) the monosaccharide composition obtained in FACE is peculiar in the sense that next to Fuc, Man, GalNac, GlcNac and NeuAc also Rib was determined; 7) HPAE-PAD analysis identified NeuAc subtypes; 8) in vitro, glycosylation of rat prolactin modulates immune recognition through steric hindrance of the access to the epitope sites.


Assuntos
Oligossacarídeos/química , Prolactina/química , Prolactina/isolamento & purificação , Animais , Cromatografia Líquida de Alta Pressão , Eletroforese em Gel de Poliacrilamida , Feminino , Glicosilação , Immunoblotting , Isoformas de Proteínas/química , Isoformas de Proteínas/isolamento & purificação , Ratos , Ratos Wistar
8.
Arch Physiol Biochem ; 107(4): 312-22, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10779827

RESUMO

To gain an insight in the routing, processing and export of rat prolactin, rat pituitary cells were cultured in serum-free medium in the presence of cycloheximide, carbonyl cyanide m-chlorophenylhydrazone, Brefeldin A and monensin. The potential influence of these perturbants, whose well documented effects are the altering of protein synthesis and transport, was studied on rat prolactin molecular size isoforms appearing in cellular extracts and in culture medium. The outcome of the culture experiments as recorded in vertical SDS-PAGE, thiol gradient electrophoresis and sequential SDS-PAGE followed by prolactin specific immunoblotting and densitometry, was as follows: (1) at the cellular level we were able to characterize a novel 36 kDa protein as a disulphide-bridged oligomeric precursor prolactin, which is presumably rapidly transformed in the cis/medial Golgi; to designate monomeric rat prolactin as an early Golgi protein and t o advance evidence that the main processing of the glycosylated rat prolactin is a cis/medial Golgi event; (2) in release none of the perturbants disturbed the relative distribution of monomeric and glycosylated rat prolactin, the main molecular size isoforms currently secreted by untreated pituitary cells, or induced the appearance of transformed molecular size isoforms; (3) the secretion mode indicates that rat prolactin is released via the regulated pathway in the presence of the perturbants used.


Assuntos
Hipófise/metabolismo , Prolactina/biossíntese , Prolactina/metabolismo , Precursores de Proteínas/biossíntese , Precursores de Proteínas/metabolismo , Animais , Brefeldina A/farmacologia , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Células Cultivadas , Meios de Cultura Livres de Soro , Cicloeximida/farmacologia , Eletroforese em Gel de Poliacrilamida , Feminino , Complexo de Golgi/metabolismo , Ionóforos/farmacologia , Monensin/farmacologia , Hipófise/efeitos dos fármacos , Inibidores da Síntese de Proteínas/farmacologia , Ratos , Ratos Wistar , Desacopladores/farmacologia
9.
J Neuroendocrinol ; 8(9): 721-30, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8877821

RESUMO

The modulation of both the molecular size heterogeneity and the relative distribution of rat prolactin variants, synthesized and secreted in vitro by rat pituitary cells in the course of postnatal ontogeny and in gestation, lactation and weaning was investigated by SDS-PAGE, immunoblotting, radioimmunological techniques and O-sialoendopeptidase digestion. The outcome of the experiments is as follows: 1) from day 1 of postnatal life 20-, 23-, 26-, 40-44 kDa and oligomeric rat prolactin isoforms were stored and secreted; 2) perinatal life is characterized by a high degree of variability of prolactin size isoforms and their respective repartition in storage and release; in addition to the major variants, transient ones of M, 25-, 28-, 33- and 36 kDa were secreted and/or stored; 3) O-sialoglycoprotease digestion of pituitary cell lysate gave good evidence for 25 kDa prolactin being a glycoform; 4) at 1 month of age 16 kDa rat prolactin appeared and persisted over the whole postnatal span (1 day-->1 year) but only in stored form; 5) the physiology of gestation was essentially characterized by the M(r)-modulation of the glycoform (26 kDa-->26.3 kDa) and the virtual absence of stored 26 kDa rat prolactin at week 1 of pregnancy; 6) in lactation and weaning uncommon multiple banding was observed in secreted oligomeric prolactin; 7) in pregnancy, lactation and weaning the differential distribution of released and stored prolactin isoforms displayed a considerable intra- and intervariability; 8) in the vast array of size isoforms observed in all our experiments monomeric 23 kDa prolactin was always the dominating variant. In conclusion, the molecular size heterogeneity and the differential distribution of secreted and stored rat pituitary prolactin is considerably influenced by age and physiological stimuli. The nature of polymeric prolactin and of the transient variants is presently unclear, and the exact physiological role of molecular heterogeneity modulation is unknown, both in humans and rat, but the patterns of change we observed in definite stages of life, suggest that this phenomenon is important in the maturation of the hypothalamus-pituitary axis and in the metabolic and hormonal changes accompanying gestation.


Assuntos
Hipófise/fisiologia , Prolactina/metabolismo , Animais , Feminino , Glicosilação , Isomerismo , Lactação/fisiologia , Hipófise/embriologia , Hipófise/crescimento & desenvolvimento , Gravidez , Prolactina/biossíntese , Ratos , Ratos Wistar , Desmame
10.
Endocrine ; 3(1): 61-8, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21153238

RESUMO

The secretion of 23 kDa prolactin by rat pituitary cells has been thoroughly investigated, but secretion of glycosylated rat prolactin is not currently known. This is mainly due to the lack of an antiserum which is solely specific for glycosylated rat prolactin and therefore we studied the basal secretion of this variant by an indirect method. Rat pituitary cells were cultured in total culture medium and three different serum-free media (DMEM, keratinocyte-serum-free medium, protein-free hybridoma medium) and secretion of 23 kDa and glycosylated rat prolactin was recorded by radioactive techniques and immunoblotting. The pituitary cell quality was monitored by electron microscopy, cell activation-and cell death assessment. In short-range culture (2 days) the pituitary cell quality and behaviour was very good and comparable in total culture medium, DMEM and keratinocyteserum-free medium, i.e. numerous secretory granules, moderate amount of ER, cristae well in place in the mitochondriae. In medium-range culture (8 days) only cells cultured in total culture medium and DMEM presented a parallel behaviour: migration of cells toward each other, marked degranulation, massive array of ER. The inner membrane of the mitochondria was no longer folded into cristae leaving an unoccupied central space. At day 2 of the culture span secretion of 23 kDa rat prolactin was very comparable in all media used; hereafter, secretion of 23 kDa rat prolactin in total culture medium and DMEM assumed the well known pattern of peaking and slowing down, whereas in the other serumfree media it steadily decreased over the culture span. Pertaining to the important novel point of glycosylated rat prolactin secretion, it was low in comparison to the one of 23 kDa rat prolactin and it assumed a near steady pattern in all media used. 26 kDa rat prolactin was identified as the preferentially secreted glycoform, and the 23 kDa isoform as the major secretory product of rat pituitary lactotroph cells.

11.
J Neuroendocrinol ; 5(6): 669-76, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8680440

RESUMO

Rat pituitary homogenates were submitted to differential and density gradient centrifugation. Subcellular fractions as well as the purified secretory granules were examined in electron microscopy, radioimmunological techniques, protease digestion, alkaline treatment and immunoblotting. The global outcome of these experiments was that: 1) the glycosylated rPRL was foremost recorded in the crude secretory granular fraction, also in the microsomal fraction and the cytosol, but virtually not in the plasma membrane fraction; 2) in purified secretory granules glycosylated rPRL appeared as an array of near Mr, such as was formerly obtained by enzymatic deglycosylation; 3) protease digestion and ice-cold alkaline treatment of the secretory granules showed that 23,000 rPRL appears in three different physicochemical states in these organelles: unsequestered within a closed system, membrane-bounded and bound state; 4) likewise treatment of microsomal vesicles showed that 23,000 and glycosylated rPRL are sequestered in these bodies, but apparently 23,000 rPRL appears as both integral membrane-bound and released from the lumen, whereas glycosylated rPRL is chiefly retained as an integral membrane protein. 5) dopamine alters the pattern of glycosylation as well in Mr as in relative percentages of the molecular variants. The systematical occurrence of the array of near Mr glycosylated rPRL is biosynthesized as a pool of proteins with a different degree of glycosylation. On the basis of our data, we speculate that selection of definite molecular variants from this pool could play an important role in the biological function of 23,000 rPRL and that oligosaccharides could perhaps target the glycosylated forms of rPRL to specific sites of action.


Assuntos
Grânulos Citoplasmáticos/metabolismo , Adeno-Hipófise/metabolismo , Prolactina/metabolismo , Frações Subcelulares/metabolismo , Animais , Autorradiografia , Centrifugação com Gradiente de Concentração , Grânulos Citoplasmáticos/ultraestrutura , Dopamina/metabolismo , Eletroforese em Gel de Poliacrilamida , Feminino , Glucose/metabolismo , Hidrólise , Immunoblotting , Microscopia Eletrônica , Adeno-Hipófise/ultraestrutura , Radioimunoensaio , Ratos , Ratos Wistar , Frações Subcelulares/ultraestrutura
12.
Artigo em Inglês | MEDLINE | ID: mdl-7684281

RESUMO

In this report the structure of the novel polypeptide h3, isolated from subsets of tissues of a single species, and the structural similarity between interspecies h3 were investigated by peptide mapping of enzymatic and chemical cleavage fragments of h3 in one-dimensional SDS-PAGE; the peptide maps were commented on in comparison with the known sequence of 21 kDa protein, a h3-like ox brain protein. The following results were obtained: peptides generated by chymotrypsin, protease XX, BNPS-skatole and CNBr cleavage of different tissues in a single species were strikingly identical, whereas peptide maps obtained from analogue tissues in different species revealed slight structural differences. Possible ligand-h3 binding was studied by comparing the c.d. spectra of native h3, and h3 incubated with several phospholipids. Given the presence of h3 or h3-like protein in rat and human platelets, h3 was also assessed in platelet aggregation in the presence of h3 and specific anti-h3 antiserum. So far, the results emphasize the unique intra- and interspecies molecular form of h3, allow us to assign to known amino acid sequence of 21 kDa to a large extent to human h3, but do not identify h3 as a phospholipid binding protein.


Assuntos
Fígado/química , Proteínas Musculares/química , Proteínas do Tecido Nervoso/química , Mapeamento de Peptídeos , Proteínas/química , Proteína de Ligação a Androgênios , Animais , Especificidade de Anticorpos , Bovinos , Dicroísmo Circular , Humanos , Ligantes , Proteínas do Tecido Nervoso/fisiologia , Proteína de Ligação a Fosfatidiletanolamina , Agregação Plaquetária/fisiologia , Prostateína , Ligação Proteica , Proteínas/fisiologia , Secretoglobinas , Especificidade da Espécie , Uteroglobina
13.
J Neuroendocrinol ; 3(4): 375-81, 1991 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19215479

RESUMO

Abstract In the rat two major molecular variants of prolactin are recorded i.e. 23,000 M(r) and glycosylated 26,000 M(r). In order to further characterize the glycosylated 26,000 rat prolactin molecular variant, rat pituitary cell lysates were digested with several glycoen-zymes and the digestion products submitted to sodium dodecyl sulphate polyacrylamide gel electrophoresis and subsequent immunoblotting. The results were as follows: treatment with 1) neuraminidase, specific for sialic acid, yielded an M(r) decrease of the glycosidic variant from 26,000 to 24,500, 23,800, 23,000 and 22,000; 2) endo-alpha-N-acetylgalactosaminidase, which releases the disaccharide Gal (beta 1-3) GalNac from O-glycans, split 26,000 rat prolactin into a doublet of M(r) 26,000 to 25,500; and 3) mixed exoglycosidases from Turbo cornutus caused a gradual M(r) shift from 26,000 to 23,000. Affinity chromatography on wheat germ agglutinin Sepharose 6MB and soybean agglutinin agarose of rat pituitary homogenates and competitive inhibition tests showed that glycosylated rat prolactin has distinct affinity for these lectins. From the experimental data it is proposed that glycosylated rat prolactin is O-linked through threonine by the disaccharide Gal (beta 1-3) GalNac and possesses at least GalNac, and/or Gal and sialyl residues.

14.
J Neurochem ; 52(4): 1123-6, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2926393

RESUMO

Recently we reported the isolation and partial biochemical characterization of the novel polypeptide h3 from human brain and liver. In this report, the physicochemical characterization is further established by the use of several analytical methods. The following results were obtained: the ultraviolet absorption spectrum is not influenced by pH, and the circular dichroism (CD) spectrum reveals that this protein has no alpha-helices, whereas approximately 25% of the polypeptide chain is found to be folded as a beta-pleated sheet structure. Neither the conformation of h3 as assessed by CD nor the titration kinetics of sulfhydryl groups with Ellman's reagent are affected by the presence of the ions K+, Na+, Ca2+, and Mg2+. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) in a beta-mercaptoethanol gradient and Cleveland sequential SDS-PAGE showed that the frequent formation of h3 polymers and doublets, as observed earlier, is almost exclusively due to disulfide bonding.


Assuntos
Proteínas do Tecido Nervoso , Peptídeos , Proteínas , Proteína de Ligação a Androgênios , Fenômenos Químicos , Físico-Química , Dicroísmo Circular , Eletroforese em Gel de Poliacrilamida , Humanos , Peso Molecular , Proteína de Ligação a Fosfatidiletanolamina , Conformação Proteica , Raios Ultravioleta
15.
Eur J Cancer Clin Oncol ; 25(3): 513-25, 1989 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2703006

RESUMO

A total of 254 patients with stages T1-3a/N0-1/M0 operable breast cancer were randomized to either surgery alone or surgery plus adjuvant chemoimmunotherapy (LMF + BCG). Ten-year results are presented for RFS (relapse-free survival) and OAS (overall survival) in the whole patient population as well as in the most important menopausal and nodal subgroups. LMF + BCG significantly increased RFS in the whole patient population as well as in node-positive women. The earlier impressive RFS and OAS gains for node-negative patients were fading after 5 and 8 years respectively, leaving marginal trends in favour of the LMF + BCG treated women. Node-positive patients treated with LMF + BCG continue to demonstrate a marginal gain in RFS up to 10 years. This gain is nearly exclusively expressed in postmenopausal node-positive women, an observation which can be made in the node-negative patient group as well. Despite the still continuing increase in RFS,' no OAS benefit was observed for node-positive women with LMF + BCG at any time of the study. Dose still remains a critical factor in cancer therapy. However, at 10 years of follow-up, a full dose of LMF (greater than or equal to 90%) during the six cycles no longer affects OAS favourably. There was no indication of any adverse long-term toxicity of LMF + BCG in our study after a median follow-up of 10 years, especially no increase of second tumours. In the node-negative patient population, the presence or absence of intramammary lymphatic infiltration seems to be a significant prognostic factor within this nodal subgroup.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Vacina BCG/uso terapêutico , Neoplasias da Mama/terapia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/cirurgia , Clorambucila/administração & dosagem , Terapia Combinada , Feminino , Fluoruracila/administração & dosagem , Seguimentos , Humanos , Metástase Linfática/terapia , Mastectomia Radical Modificada , Metotrexato/administração & dosagem , Pessoa de Meia-Idade
16.
J Endocrinol ; 120(2): 201-6, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2926296

RESUMO

Prolactin and GH cells from rat pituitary glands were separated into three main fractions on discontinuous Percoll gradient layers. SDS-PAGE and subsequent immunoblotting of these fractions revealed that: (1) multiple rat prolactin (rPRL) molecular variants were present in total culture, Percoll layer 1 and 2; four variants were clear-cut: Mr approximately 23,000, Mr doublet approximately 25,000-26,000, Mr approximately 40,000 and Mr approximately 42,000; (2) cell cytosol from Percoll gradient layer 1 was particularly enriched in prolactin; (3) cells from gradient layer 1 secreted into the culture medium only prolactin in detectable amounts; (4) three distinct molecular forms of rat growth hormone (rGH) were recorded in layer 3: Mr approximately 36,000, 24,000 and 20,000; the 20,000 variant was paramount; and (5) cells from layer 3 secreted both rPRL and rGH into the culture medium. Reduction experiments showed that, on the one hand, 42,000 and 40,000 rPRL variants and, on the other hand, 36,000 rGH variants are disulphide-bridged dimers. An important finding was the presence of glycosylated rPRL and rGH: indeed Concanavalin A-Sepharose 4B affinity chromatography indicated that 26,000 rPRL and 24,000 rGH display a very strong affinity for lectin. Competitive inhibition tests showed that this affinity is specific and not due to hydrophobic binding. When rPRL was submitted to deglycosylation in conditions specific for O-linked glycoproteins, the 26,000 rPRL variant disappeared. The biological role of glycosylated rPRL is as yet unknown.


Assuntos
Hormônio do Crescimento/isolamento & purificação , Adeno-Hipófise/metabolismo , Prolactina/isolamento & purificação , Animais , Separação Celular , Células Cultivadas , Dissulfetos , Feminino , Hormônio do Crescimento/análogos & derivados , Isomerismo , Peso Molecular , Prolactina/análogos & derivados , Conformação Proteica , Ratos
17.
J Neuroendocrinol ; 1(6): 427-31, 1989 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-19210412

RESUMO

Abstract Prolactin cells derived from the anterior pituitaries of female rats were cultured in the presence of tunicamycin, swainsonine, castanospermine, beta-hydroxynorvaline and monensin in order to study their effect on the post-translational processing of the M(r) 17,000, 23,000 and 26,000 prolactin molecular forms. Sodium-dodecyl-sulphate polyacrylamide electrophoresis and subsequent immunoblotting revealed that: 1) tunicamycin, swainsonine and castanospermine, compounds that are essentially known as inhibitors of the N-glycosylation processus, had no effect on M(r) 17,000, 23,000 and 26,000 rat prolactin; 2) betahydroxynorvaline, which has been assumed to inhibit processing of pre-prolactin to mature 23,000 prolactin, did not increase the synthesis of 26,000 rat prolactin. In case of inhibition of the processing of a pre-prolactin to mature prolactin, one would expect an increase of the pre-prolactin; consequently, we could not establish the 26,000 rat prolactin, we revealed in immunoblotting, as a pre-prolactin; 3) monensin affected the post-translational processing of 17,000 and 26,000 rat prolactin, but left the 23,000 mature form intact. This is an important finding for the following reasons: monensin blocks the transport of secretory and membrane proteins, and this blockade prevents the cleavage of these molecules; indeed, production of 17,000 rat prolactin, a form of cleaved prolactin, was inhibited. Monensin also affects glycosylation and 26,000 rat prolactin has been identified as a presumably O-iinked glycosylated variant. The fact that its synthesis is inhibited by monensin treatment, but not by inhibitors of the N-linked process, particularly tunicamycin, and that 26,000 rat prolactin is susceptible to mild alkali and decomposition via beta-elimination are decisive arguments in favour of the O-linked glycosidic linkage.

18.
J Neurochem ; 50(4): 1210-4, 1988 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-3279164

RESUMO

Recently we reported the isolation and partial biochemical characterization of a novel polypeptide, h3, from the human brain and liver. Thin-layer isoelectric focusing showed that the polypeptide was ubiquitously distributed throughout the human brain. Immunophosphatase transfer electrophoresis showed that this protein was localized in several mammalian species and different tissues. In addition, h3 or h3-like protein was demonstrated in subsets of tissues from one avian species. Protein h3 was present in epithelial and muscular tissue, as well as in nervous tissue; however, for all species investigated, it was most abundant in CNS and muscle.


Assuntos
Proteínas do Tecido Nervoso/análise , Proteínas/análise , Proteína de Ligação a Androgênios , Animais , Química Encefálica , Bovinos , Galinhas , Sistema Digestório/análise , Eletroforese em Gel de Poliacrilamida , Humanos , Técnicas Imunoenzimáticas , Rim/análise , Fígado/análise , Miocárdio/análise , Proteína de Ligação a Fosfatidiletanolamina , Prostateína , Ratos , Ratos Endogâmicos , Secretoglobinas , Ovinos , Especificidade da Espécie , Baço/análise , Distribuição Tecidual , Uteroglobina
19.
J Clin Immunol ; 6(4): 319-25, 1986 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-3091630

RESUMO

A patient affected with multiple myeloma displayed in the serum, urine, and cerebrospinal fluid a paraprotein with identical electrophoretic mobility. The paraprotein, which was polymeric, appeared in the serum and cerebrospinal fluid mainly as the dimer and tetramer, whereas in the urine the tetramer was predominant. The myeloma protein, identified as an IgA1 kappa, was isolated from the serum and urine and submitted to structural analysis. For reasons of scarcity of material, it was decided to approach the structure of the cerebrospinal fluid paraprotein by means of antiidiotypic antiserum. Complete idiotypic identity between, on the one hand, cerebrospinal fluid and, on the other hand, IgA1 isolated from serum and urine and F(ab)2 alpha derived from serum IgA1 was observed. Adsorption experiments confirmed the idiotypic identity among the three biological fluids. Although the blood-brain barrier of the patient was only slightly disturbed, IgA polymers of MW varying from approximately 280,000 to approximately 840,000 appeared in the cerebrospinal fluid. Consequently the results are good evidence for synthesis within the central nervous system by subsequent generations of a malignant B-cell line which invaded the central nervous system.


Assuntos
Imunoglobulina A/líquido cefalorraquidiano , Cadeias kappa de Imunoglobulina/líquido cefalorraquidiano , Mieloma Múltiplo/líquido cefalorraquidiano , Proteínas do Mieloma/líquido cefalorraquidiano , Adulto , Barreira Hematoencefálica , Sistema Nervoso Central/metabolismo , Humanos , Imunoglobulina A/análise , Idiótipos de Imunoglobulinas/análise , Cadeias kappa de Imunoglobulina/análise , Masculino , Mieloma Múltiplo/análise , Proteínas do Mieloma/análise
20.
J Clin Chem Clin Biochem ; 22(10): 653-9, 1984 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-6210342

RESUMO

Total protein content, alpha 1-antitrypsin, alpha 2-macroglobulin and plasminogen levels and measles antibody titers were determined in serum and plasma from patients affected with multiple sclerosis and patients affected with non-neurological diseases. The results were compared with those from a control group of healthy donors. Both multiple sclerosis patients and patients affected with non-neurological diseases differed from controls for the following parameters: total protein, plasminogen and measles antibody activity. However, when studied longitudinally the different parameters were not altered to the same degree in multiple sclerosis and non-neurological diseases, a fact which is translated in the difference of significance levels. Individual plasminogen values were very often higher in non-neurological diseases than in multiple sclerosis, whereas for increased measles antibody titers it was the reverse. Also, there were no notable changes in alpha 1-antitrypsin and alpha 2-macroglobulin values in multiple sclerosis, whereas in some non-neurological disease patients particularly high alpha 1-antitrypsin and alpha 2-macroglobulin values were observed. In the multiple sclerosis patients, no correlations existed between the duration of the disease and disturbed biochemical parameters, or between the disturbed parameters themselves.


Assuntos
Anticorpos Antivirais/análise , Vírus do Sarampo/imunologia , Esclerose Múltipla/imunologia , Plasminogênio/análise , Inibidores de Proteases/sangue , Adulto , Proteínas Sanguíneas/análise , Humanos , Pessoa de Meia-Idade , Esclerose Múltipla/sangue , Controle de Qualidade , Fatores de Tempo , alfa 1-Antitripsina/análise , alfa-Macroglobulinas/análise
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