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1.
Artigo em Inglês | MEDLINE | ID: mdl-32062367

RESUMO

Protein-arginine methyltransferases catalyze the methylation of the guanidine (NG) group of proteinic L-arginine (Arg) to produce monomethyl and dimethylarginine proteins. Their proteolysis releases the free amino acids monomethylarginine (MMA), symmetric dimethylarginine (SDMA) and asymmetric dimethylarginine (ADMA), respectively. MMA, SDMA and ADMA are inhibitors of the nitric oxide synthase (NOS) activity. High circulating and low urinary concentrations of ADMA and SDMA are considered risk factors in the cardiovascular and renal systems, mainly due to their inhibitory action on NOS activity. Identity, biological activity and concentration of NG-methylated proteins are largely unknown. The present study addressed these issues by using GC-MS and LC-MS/MS approaches. GC-MS was used to quantify free ADMA released by classical HCl-catalyzed hydrolysis of three synthetic Arg-vasopressin (V) peptides and of unknown endogenous NG-dimethylated proteins. The cyclic (c) disulfide forms of Arg-vasopressin analogs, i.e., Arg-vasopressin (cV-Arg-Gly-NH2), asymmetrically NG-dimethylated vasopressin (cV-ADMA-Gly-NH2) and symmetrically NG-dimethylated vasopressin (cV-SDMA-Gly-NH2) were used as model peptides in quantitative GC-MS analyses of ADMA, SDMA and other expected amino acids from the hydrolyzed Arg-vasopressin analogs. cV-ADMA-Gly-NH2 and cV-SDMA-Gly-NH2 were discriminated from cV-Arg-Gly-NH2 by LC-MS and LC-MS/MS, yet they were indistinguishable from each other. The same applies to the respective open (o) reduced and di-S-acetamide forms of oV-ADMA-Gly-NH2, oV-SDMA-Gly-NH2 and oV-Arg-Gly-NH2. Our LC-MS and LC-MS/MS studies suggest that the Arg-vasopressin analogs form [(M-H)]+ and [(M-H)+H]+ in the positive ESI mode and undergo in part conversion of their terminal Gly-NH2 (NH2, 16 Da) group to Gly-OH (OH, 17 Da). The product ion mass spectra of the di-S-acetamide forms are complex and contain several intense mass fragments differing by 1 Da. cV-ADMA-Gly-NH2 and cV-SDMA-Gly-NH2 induced platelet aggregation in platelet-rich human plasma with moderately different initial velocity and maximal aggregation rates compared to cV-Arg-Gly-NH2. Previous studies showed that human red blood cells are rich in large (>50 kDa) ADMA-containing proteins of unknown identity. Our LC-MS/MS proteomic study identified several membrane and cytosolic erythrocytic NG-dimethylated proteins, including spectrin-α (280 kDa), spectrin-ß (247 kDa) and protein 4.1 (80 kDa). Being responsible for the stability of the erythrocyte membrane, the newly identified main targets for NG-dimethylation in human erythrocytes should be given a closer look in erythrocytic diseases like hereditary spherocytosis.


Assuntos
Arginina Vasopressina , Cromatografia Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Guanidina/química , Espectrometria de Massas em Tandem/métodos , Arginina/análogos & derivados , Arginina/análise , Arginina/sangue , Arginina/química , Arginina Vasopressina/análise , Arginina Vasopressina/sangue , Arginina Vasopressina/química , Proteínas Sanguíneas/análise , Proteínas Sanguíneas/química , Humanos , Modelos Lineares , Masculino , Peptídeos/análise , Peptídeos/sangue , Peptídeos/química , Projetos Piloto , Processamento de Proteína Pós-Traducional
2.
PLoS One ; 15(1): e0228006, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31999745

RESUMO

A concerted action on the part of international agencies and national governments has resulted in the near-eradication of poliomyelitis. However, both the oral polio vaccine (OPV) and the inactivated polio vaccine (IPV) have deficiencies which make them suboptimal for use after global eradication. OPV is composed of attenuated Sabin strains and stimulates robust immunity, but may revert to neurovirulent forms in the intestine which can be shed and infect susceptible contacts. The majority of IPV products are manufactured using pathogenic strains inactivated with formalin. Upon eradication, the production of large quantities of pathogenic virus will present an increased biosecurity hazard. A logical ideal endgame vaccine would be an inactivated form of an attenuated strain that could afford protective immunity while safely producing larger numbers of doses per unit of virus stock than current vaccines. We report here the development of an ionizing radiation (IR)-inactivated Sabin-based vaccine using a reconstituted Mn-decapeptide (MDP) antioxidant complex derived from the radioresistant bacterium Deinococcus radiodurans. In bacteria, Mn2+-peptide antioxidants protect proteins from oxidative damage caused by extreme radiation exposure. Here we show for the first time, that MDP can protect immunogenic neutralizing epitopes in picornaviruses. MDP protects epitopes in Polio Virus 1 and 2 Sabin strains (PV1-S and PV2-S, respectively), but viral genomic RNA is not protected during supralethal irradiation. IR-inactivated Sabin viruses stimulated equivalent or improved neutralizing antibody responses in Wistar rats compared to the commercially used IPV products. Our approach reduces the biosecurity risk of the current PV vaccine production method by utilizing the Sabin strains instead of the wild type neurovirulent strains. Additionally, the IR-inactivation approach could provide a simpler, faster and less costly process for producing a more immunogenic IPV. Gamma-irradiation is a well-known method of virus inactivation and this vaccine approach could be adapted to any pathogen of interest.


Assuntos
Raios gama , Vacina Antipólio de Vírus Inativado/imunologia , Vacina Antipólio Oral/imunologia , Animais , Anticorpos Neutralizantes/imunologia , Ensaio de Imunoadsorção Enzimática , Genoma Viral , Células HeLa , Humanos , Estresse Oxidativo , Peptídeos/sangue , Poliovirus/genética , Poliovirus/imunologia , Poliovirus/patogenicidade , Poliovirus/ultraestrutura , Ratos Wistar , Proteínas Virais/metabolismo
3.
Adv Clin Chem ; 94: 1-30, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31952570

RESUMO

Hypertensive disorders of pregnancy (HDP) is the most common and widely known as serious complication of pregnancy. As this syndrome is a major leading cause of maternal, fetal, and neonatal morbidity/mortality worldwide, many studies have sought to identify candidate molecules as potential disease biomarkers (DBMs) for use in clinical examinations. Accumulating evidence over the past 2 decades that the many proteolytic peptides appear in human humoral fluids, including peripheral blood, in association with an individual's health condition. This review provides the potential utility of peptidomic analysis for monitoring for pathophysiological status in HDP, and presents an overview of current status of peptide quantification technology. Especially, the technical limitations of the methods used for DBM discovery in the blood are discussed.


Assuntos
Hipertensão/sangue , Peptídeos/sangue , Complicações Cardiovasculares na Gravidez/sangue , Biomarcadores/sangue , Feminino , Humanos , Hipertensão/complicações , Gravidez , Complicações Cardiovasculares na Gravidez/fisiopatologia
4.
Maturitas ; 132: 24-29, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31883659

RESUMO

OBJECTIVE: To evaluate trabecular bone score (TBS) in Spanish postmenopausal women from our area. To analyze its relationship with bone mineral density (BMD), bone quantitative ultrasound (QUS) and serum concentrations of 25-hydroxyvitamin D (25(OH)D), intact parathyroid hormone (PTH) and bone turnover markers. STUDY DESIGN: A total of 1450 postmenopausal women aged 44-94 (62 ± 10) participated in this cross-sectional study nested in a population-based cohort. BMD and TBS were assessed by DXA. QUS measurements were performed using a Sahara Clinical Sonometer. Serum 25(OH)D, PTH, P1NP, ß-CTX were determined by electrochemiluminescence. RESULTS: Mean TBS of postmenopausal women in our region was 1.341 ± 0.111. Nearly 50 % of them had normal values. Only 11 % had scores compatible with a clearly degraded microarchitecture. TBS decreased with age, correlated negatively with BMI and was lower in current smokers than in non-smokers. An association was observed between TBS and QUS, although the association was weak and lower than that found between TBS and BMD or QUS and BMD. No association was found between TBS and 25(OH)D, PTH or bone turnover markers. CONCLUSIONS: Half of postmenopausal women in our region have TBS values that indicate a preserved microarchitecture. Only about 10 % have scores compatible with a clearly degraded microarchitecture. A weak association was observed between TBS and QUS, suggesting that the two techniques capture different aspects of bone microarchitecture. The absence of association with 25(OH)D, PTH, and bone turnover markers may be due to the fact that TBS assesses a specific (mostly trabecular) part of the skeleton, whilst the three serum factors are related to the whole skeleton.


Assuntos
Densidade Óssea , Osso Esponjoso/diagnóstico por imagem , Pós-Menopausa , Absorciometria de Fóton , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Colágeno Tipo I/sangue , Estudos Transversais , Feminino , Humanos , Pessoa de Meia-Idade , Hormônio Paratireóideo/sangue , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pós-Menopausa/sangue , Pró-Colágeno/sangue , Espanha , Ultrassonografia , Vitamina D/análogos & derivados , Vitamina D/sangue
5.
Adv Clin Exp Med ; 28(11): 1571-1575, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31756066

RESUMO

Despite great advances in medicine, the proper treatment of arterial hypertension (AH), diabetes mellitus (DM) and chronic kidney disease (CKD) remains a major challenge. Untreated, undiagnosed AH or DM may lead to the development of CKD and consequently to the occurrence of cardiovascular events. Adropin and irisin are newly discovered proteins which may play a role in the development and progression of the chronic diseases mentioned above. Endothelium dysfunction could be a bonding point. The following review paper focuses on adropin and irisin concentrations and their correlations in AH, DM and CKD. Lower adropin concentrations have been measured in patients with primary AH when compared to healthy volunteers. Irisin has reduced blood pressure on nitric oxide (NO)-dependent pathways in experimental studies; a negative correlation between irisin and blood pressure values has also been observed in preeclamptic women. Irisin also plays a role in insulin sensitivity and metabolic disorders. Lower irisin levels have been observed in patients with DM type 2 in comparison to a nondiabetic control group. It is also lower in the serum of pregnant women with gestational DM. A negative correlation between irisin and estimated glomerular filtration rate (EGFR) has also been noted. Adropin and irisin are newly described myokines measured in human plasma in healthy and disease status. Their exact function has not been specified yet and requires further studies.


Assuntos
Diabetes Mellitus/fisiopatologia , Fibronectinas/sangue , Hipertensão/fisiopatologia , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Peptídeos/sangue , Insuficiência Renal Crônica/fisiopatologia , Biomarcadores/sangue , Proteínas Sanguíneas , Diabetes Mellitus/sangue , Diabetes Mellitus/metabolismo , Fibronectinas/metabolismo , Humanos , Hipertensão/sangue , Hipertensão/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/metabolismo
6.
Arch Esp Urol ; 72(9): 948-954, 2019 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-31697256

RESUMO

OBJECTIVE: To examine the predictive value of osteocalcin (OC) and C-terminal telopeptide (CTX) levels for jaw osteonecrosis in high-risk prostate cancer (PCa) patients taking bisphosphonates (BPs). METHODS: Twenty-four patients were prospectively recruited in this study and followed from 2011 to 2015. All patients were diagnosed with metastatic PCa with secondary bone deposits and were on androgen deprivation therapy (ADT). All participants were started on 4mg of zoledronic acid intravenously every 4 weeks for two years. The patients were reviewed every three months with full blood count, blood biochemistry, PSA and measurement of OC and CTX. Patients also underwent dental/oral examination. OC and CTX levels in serum were calculated using the ELISA method. RESULTS: A significant decrease in PSA levels was found (ß=-0.06, SE=0.02, p=0.006). The levels of OC (ß=-0.46, SE=0.14, p=0.001) and CTX (ß=-0.01, SE=0.004, p=0.007) also decreased significantly during the two years of follow up. Osteonecrosis of the jaw was identified in three patients at two years. Patients with osteonecrosis also showed a decrease in OC and CTX levels. The mean OC reduction was 77.3% for patients with osteonecrosis and 12.6% for patients without osteonecrosis. The mean CTX reduction was 44.1% for patients with osteonecrosis and 9.62% for patients without osteonecrosis. CONCLUSION: Our study demonstrated no clear association between the levels of serum OC and CTX and bisphosphonate-related osteonecrosis of the jaw (BRONJ). To date, there is no clinically useful biomarker for the prediction of jaw osteonecrosis. More studies are needed using different bone turnover markers in order to identify patients at risk for BRONJ.


Assuntos
Osteonecrose da Arcada Osseodentária Associada a Difosfonatos , Conservadores da Densidade Óssea , Osteocalcina , Peptídeos , Neoplasias da Próstata , Antagonistas de Androgênios , Osteonecrose da Arcada Osseodentária Associada a Difosfonatos/diagnóstico , Conservadores da Densidade Óssea/uso terapêutico , Colágeno Tipo I , Difosfonatos , Humanos , Masculino , Osteocalcina/sangue , Peptídeos/sangue , Valor Preditivo dos Testes , Estudos Prospectivos , Neoplasias da Próstata/tratamento farmacológico
7.
Prague Med Rep ; 120(2-3): 84-94, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31586507

RESUMO

Ageing is associated with the accumulation of damage to all the macromolecules within and outside cells leading to progressively more cellular and tissue defects and resulting in age-related frailty, disability and disease. As a result of the aging process the bone deteriorates in composition, structure and function. Age-related musculoskeletal losses are a major public health burden because they can cause physical disability and increased mortality. We tried to find out on a small set of old women, without risk factors for osteoporosis, what caused them the loss of bone minerals. All 492 women had just only one risk factor - the old age. Laboratory findings have shown a decreased serum C telopeptide and low serum alkaline phosphatase circulating markers, used to quantify bone resorption and formation, and very low level of vitamin D. Very low level of vitamin D that disrupted calcium absorption through the intestine, and decreased calcemia increased parathyroid hormone levels with resulting bone effect. The manifestation of physiological aging is worsening eyesight, peripheral neuropathy, depression, worsening of physical condition, skin aging, sarcopenia and bone mineral loss. Senile osteoporosis, which is not caused by known risk factors for osteoporosis, does not appear to be a separate disease, but is part of the physiological process of aging. Treatment of senile osteoporosis should be focused on the control of secondary hyperparathyroidism by administration of vitamin D and calcium. The risk of fractures in the advanced age is determined by a large number of factors ranging from hazards in the home environment to frailty and poor balance.


Assuntos
Envelhecimento/sangue , Envelhecimento/patologia , Fosfatase Alcalina/sangue , Densidade Óssea , Cálcio/metabolismo , Colágeno Tipo I/sangue , Feminino , Humanos , Osteogênese , Osteoporose/sangue , Hormônio Paratireóideo/sangue , Peptídeos/sangue , Vitamina D/sangue
8.
Se Pu ; 37(8): 853-862, 2019 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-31642256

RESUMO

Diabetes is a systemic metabolic disorder syndrome, mainly characterized by hyperglycemia, and is associated with the dysfunction of various organs, such as liver, pancreas, intestine, adipose muscle tissue, kidney and brain. It has become a global epidemic disease that seriously threatens human health. Therefore, mapping the global molecular signatures of diabetes-related disease spectrum can provide more comprehensive data to understand early clinical diagnosis, molecular typing, and pathological processes involved in diabetes mellitus. In this study, we performed a quantitative differential analysis on the endogenous peptidome of the serum samples obtained from healthy, prediabetes and type 2 diabetes groups to explore the peptidomics evolution in the development of diabetes. Partial least squares-discriminant analysis (PLS-DA) was used for pattern recognition. A nonparametric test was examined to find out the significantly changed endogenous peptides. As a result, 690 serum endogenous peptides were identified totally, among which 163 endogenous peptides were statistically different among the three groups. This could be promising quantitative peptidomics data for early screening, diagnosis and molecular typing of type 2 diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Peptídeos/sangue , Proteoma/análise , Humanos
9.
Maturitas ; 129: 12-22, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31547908

RESUMO

OBJECTIVE: To systematically evaluate the effects of bone anabolic therapies (BATs) - specifically, drug therapy with teriparatide, abaloparatide or romosozumab - on fractures, bone mineral density (BMD), and bone metabolites in postmenopausal osteoporosis. METHODS: Six computerized engines were searched through to November 2018. We selected randomized controlled trials (RCTs) evaluating the effect of BATs on postmenopausal osteoporosis and with at least 6 months of follow-up. Controls were placebo, no treatment, or bisphosphonates. Primary outcomes were vertebral and non-vertebral fractures. Secondary outcomes were: BMD determined by dual energy X-ray absorptiometry at total hip, lumbar spine, and femoral neck; N-terminal propeptide of type I procollagen (PINP); C-terminal telopeptide of type I collagen (CTX); and severe adverse events (SAE). We followed the PRISMA guidelines for reporting, and used version 2 of the Cochrane risk-of-bias tool. Frequentist network meta-analyses were performed per outcome. Effects for dichotomous and continuous outcomes were expressed as relative risks and mean differences and their 95% confidence intervals. We used p-scores to rank best treatments per outcome. RESULTS: Sixteen RCTs (n = 18,940) were evaluated. Mean ages ranged between 61 and 74 years, and follow-up times between 6 and 30 months. Four RCTs (n = 971) excluded patients with previous fractures. In contrast to placebo/no treatment, all BATs significantly reduced the risk of vertebral fractures, but no intervention significantly reduced the risk of non-vertebral fractures; abaloparatide ranked better than other interventions for both fracture types (p-scores: 0.95, and 0.89, respectively). All BATs significantly increased BMD at all locations in comparison with placebo/no treatment; romosozumab consistently ranked better than other interventions at all BMD locations (p-scores >0.86). Teriparatide ranked better than other interventions for increasing PINP. No differences in SAE were observed among treatments. CONCLUSIONS: Abaloparatide, romosozumab, and teriparatide are the best treatments, respectively, to reduce vertebral/non-vertebral fractures, increase BMD, and increase bone formation.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Conservadores da Densidade Óssea/uso terapêutico , Osteoporose Pós-Menopausa/tratamento farmacológico , Fraturas por Osteoporose/prevenção & controle , Proteína Relacionada ao Hormônio Paratireóideo/uso terapêutico , Teriparatida/uso terapêutico , Anticorpos Monoclonais/farmacologia , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/farmacologia , Colágeno Tipo I/sangue , Feminino , Humanos , Metanálise em Rede , Osteoporose Pós-Menopausa/sangue , Proteína Relacionada ao Hormônio Paratireóideo/farmacologia , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pró-Colágeno/sangue , Ensaios Clínicos Controlados Aleatórios como Assunto , Teriparatida/farmacologia
10.
Lett Appl Microbiol ; 69(5): 312-317, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31529504

RESUMO

Andrias davidianus is widely recognized in traditional medicine as a cure-all to treat a plethora of ailments. In a previous study, a novel antibacterial peptide named andricin B was isolated from A. davidianus blood. In this study, we investigated andricin B structure and its mode of action. Circular dichroism spectra suggested that andricin B adopts a random coil state in aqueous solution and a more rigid conformation in the presence of bacteria. Moreover propidium iodide/fluorescein diacetate double staining indicated that bacteria treated with andricin B were not immediately eliminated. Rather, there is a gradual bacterial death, followed by a sublethal stage. Scanning electronic microscope imaging indicates that andricin B might form pores on cell membranes, leading to the release of cytoplasmic contents. These results were consistent with flow cytometry analysis. Furthermore, Fourier transform infrared spectroscopy suggests that andricin B induces changes in the chemical properties in the areas surrounding these "pores" on the cell membranes. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study suggested the new perspectives about the mode of action of antimicrobial peptide (AMP) active against sensitive bacteria. The AMP was able to be in a random coiled state in aqueous solution but to change to a more rigid one in the presence of sensitive bacteria. Exposure to AMP might not lead to immediate death of treated bacteria, rather bacteria concentration decreased gradually flattening at a sublethal stage. These findings will help people to understand better how the AMPs activate against sensitive bacteria.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Peptídeos/química , Peptídeos/farmacologia , Urodelos/sangue , Animais , Antibacterianos/sangue , Bactérias/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Dicroísmo Circular , Testes de Sensibilidade Microbiana , Peptídeos/sangue
11.
Anticancer Res ; 39(9): 5171-5177, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31519630

RESUMO

BACKGROUND/AIM: The aim of this study was to analyze the pretreatment cytokeratin serum levels in head and neck squamous cell carcinoma (HNSCC) by three assays in relation to selected clinicopathological characteristics in an effort to find diagnostic/prognostic biomarkers for HNSCC and determine the best assay. PATIENTS AND METHODS: In total, 46 patients with HNSCC with different subsite (oropharyngeal-21 cases, hypopharyngeal-4 and laryngeal-21) were included in this prospective study. MonoTotal, Cyfra 21-1, and TPS radioimmunoassay kits were used to analyze cytokeratin fragments serum levels. RESULTS: Statistically significant differences in serum levels of TPS and Cyfra 21-1 were found between low (stage I-II)- and high-stage (stage III-IV) tumors (p=0.0057; p=0.0138 respectively). Cyfra21-1 assay showed significant differences between tumors of different sites with prominent elevation being found in oropharyngeal carcinomas and between patients with p16 positive and p16 negative HNSCC (p=0.0242), being elevated in p16 positive tumors. CONCLUSION: The present study is the first to compare cytokeratin serum levels between various subgroups of HNSCC using three different assays. Cyfra 21-1 seems to be the most useful for clinical practice. The relation between elevated Cyfra 21-1 serum levels and p16 expression requires further investigation.


Assuntos
Antígenos de Neoplasias/sangue , Biomarcadores Tumorais , Queratina-19/sangue , Peptídeos/sangue , Carcinoma de Células Escamosas de Cabeça e Pescoço/sangue , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Prognóstico , Carcinoma de Células Escamosas de Cabeça e Pescoço/mortalidade , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia
12.
BMC Bioinformatics ; 20(1): 387, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296178

RESUMO

BACKGROUND: Bioinformatics methods are helpful to identify new molecules for diagnostic or therapeutic applications. For example, the use of peptides capable of mimicking binding sites has several benefits in replacing a protein which is difficult to produce, or toxic. Using peptides is less expensive. Peptides are easier to manipulate, and can be used as drugs. Continuous epitopes predicted by bioinformatics tools are commonly used and these sequential epitopes are used as is in further experiments. Numerous discontinuous epitope predictors have been developed but only two bioinformatics tools have been proposed so far to predict peptide sequences: Superficial and PEPOP 2.0. PEPOP 2.0 can generate series of peptide sequences that can replace continuous or discontinuous epitopes in their interaction with their cognate antibody. RESULTS: We have developed an improved version of PEPOP (PEPOP 2.0) dedicated to answer to experimentalists' need for a tool able to handle proteins and to turn them into peptides. The PEPOP 2.0 web site has been reorganized by peptide prediction category and is therefore better formulated to experimental designs. Since the first version of PEPOP, 32 new methods of peptide design were developed. In total, PEPOP 2.0 proposes 35 methods in which 34 deal specifically with discontinuous epitopes, the most represented epitope type in nature. CONCLUSION: Through the presentation of its user-friendly, well-structured new web site conceived in close proximity to experimentalists, we report original methods that show how PEPOP 2.0 can assist biologists in dealing with discontinuous epitopes.


Assuntos
Biologia Computacional/métodos , Epitopos/metabolismo , Software , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/imunologia , Epitopos/química , Soros Imunes , Internet , Camundongos , Peptídeos/sangue , Peptídeos/química , Peptídeos/imunologia , Domínios Proteicos , Proteínas/química
13.
Nutrients ; 11(7)2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31261978

RESUMO

Type 2 diabetes increases bone fracture risk in postmenopausal women. Usual treatment with anti-resorptive bisphosphonate drugs has some undesirable side effects, which justified our interest in the osteogenic potential of nutrition and exercise. Since meal eating reduces bone resorption, downhill locomotion increases mechanical stress, and brief osteogenic responsiveness to mechanical stress is followed by several hours of refractoriness, we designed a study where 40-min of mechanical stress was manipulated by treadmill walking uphill or downhill. Exercise preceded or followed two daily meals by one hour, and the meals and exercise bouts were 7 hours apart. Fifteen subjects each performed two of five trials: No exercise (SED), uphill exercise before (UBM) or after meals (UAM), and downhill exercise before (DBM) or after meals (DAM). Relative to SED trial, osteogenic response, defined as the ratio of osteogenic C-terminal propeptide of type I collagen (CICP) over bone-resorptive C-terminal telopeptide of type-I collagen (CTX) markers, increased in exercise-after-meal trials, but not in exercise-before-meal trials. CICP/CTX response rose significantly after the first exercise-after-meal bout in DAM, and after the second one in UAM, due to a greater CICP rise, and not a decline in CTX. Post-meal exercise, but not the pre-meal exercise, also significantly lowered serum insulin response and homeostatic model (HOMA-IR) assessment of insulin resistance.


Assuntos
Remodelação Óssea , Diabetes Mellitus Tipo 2/terapia , Terapia por Exercício , Fraturas Ósseas/prevenção & controle , Refeições , Osteogênese , Idoso , Biomarcadores/sangue , Colágeno Tipo I/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/complicações , Feminino , Fraturas Ósseas/sangue , Fraturas Ósseas/etiologia , Fraturas Ósseas/fisiopatologia , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/sangue , Resistência à Insulina , Pessoa de Meia-Idade , Valor Nutritivo , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pós-Menopausa/sangue , Período Pós-Prandial , Pró-Colágeno/sangue , Fatores de Tempo , Resultado do Tratamento
14.
J Vet Intern Med ; 33(4): 1571-1584, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31254308

RESUMO

BACKGROUND: Angiotensin-converting enzyme 2 (ACE2) is a homologue of angiotensin-converting enzyme (ACE) and produces angiotensin peptides (APs), such as angiotensin 1-9 and 1-7 that are vasodilatory and natriuretic, and act to counterbalance angiotensin II. HYPOTHESIS: Evidence of ACE2 can be found in tissues and plasma of dogs. Equilibrium concentrations of renin angiotensin aldosterone system (RAAS) APs differ in dogs with heart disease compared to healthy dogs and recombinant human ACE2 (rhACE2) alters relative concentrations of APs. ANIMALS: Forty-nine dogs with and 34 dogs without heart disease. METHODS: Immunohistochemistry and assays for tissue and plasma ACE2 activity and equilibrium concentrations of plasma RAAS APs were performed. RESULTS: Immunolabeling for ACE2 was present in kidney and myocardial tissue. Median plasma ACE2 activity was significantly increased in dogs with congestive heart failure (CHF; 6.9 mU/mg; interquartile range [IQR], 5.1-12.1) as compared to control (2.2 mU/mg; IQR, 1.8-3.0; P = .0003). Plasma equilibrium analysis of RAAS APs identified significant increases in the median concentrations of beneficial APs, such as angiotensin 1-7, in dogs with CHF (486.7 pg/mL; IQR, 214.2-1168) as compared to those with preclinical disease (41.0 pg/mL; IQR, 27.4-45.1; P < .0001) or control (11.4 pg/mL; IQR, 7.1-25.3; P = .01). Incubation of plasma samples from dogs with CHF with rhACE2 increased beneficial APs, such as angiotensin 1-9 (preincubation, 10.3 pg/mL; IQR, 4.4-37.2; postincubation, 2431 pg/mL; IQR, 1355-3037; P = .02), while simultaneously decreasing maladaptive APs, such as angiotensin II (preincubation, 53.4 pg/mL; IQR, 28.6-226.4; postincubation, 2.4 pg/mL; IQR, 0.50-5.8; P = .02). CONCLUSIONS AND CLINICAL IMPORTANCE: Recognition of the ACE2 system expands the conventional view of the RAAS in the dog and represents an important potential therapeutic target.


Assuntos
Angiotensinas/sangue , Cardiopatias/veterinária , Peptidil Dipeptidase A/sangue , Animais , Estudos de Casos e Controles , Cães , Feminino , Cardiopatias/sangue , Cardiopatias/enzimologia , Insuficiência Cardíaca/sangue , Insuficiência Cardíaca/enzimologia , Insuficiência Cardíaca/veterinária , Imuno-Histoquímica , Rim/enzimologia , Masculino , Miocárdio/enzimologia , Peptídeos/sangue , Peptidil Dipeptidase A/análise , Sistema Renina-Angiotensina
15.
Mol Cell Proteomics ; 18(6): 1255-1268, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31154438

RESUMO

Glioblastoma multiforme (GBM) is the most aggressive brain tumor with poor prognosis to most patients. Immunotherapy of GBM is a potentially beneficial treatment option, whose optimal implementation may depend on familiarity with tumor specific antigens, presented as HLA peptides by the GBM cells. Further, early detection of GBM, such as by a routine blood test, may improve survival, even with the current treatment modalities. This study includes large-scale analyses of the HLA peptidome (immunopeptidome) of the plasma-soluble HLA molecules (sHLA) of 142 plasma samples, and the membranal HLA of GBM tumors of 10 of these patients' tumor samples. Tumor samples were fresh-frozen immediately after surgery and the plasma samples were collected before, and at multiple visits after surgery. In total, this HLA peptidome analysis involved 52 different HLA allotypes and resulted in the identification of more than 35,000 different HLA peptides. Strong correlations were observed in the signal intensities and in the repertoires of identified peptides between the tumors and plasma-soluble HLA peptidomes of the individual patients, whereas low correlations were observed between these HLA peptidomes and the tumors' proteomes. HLA peptides derived from Cancer/Testis Antigens (CTAs) were selected based on their presence among the HLA peptidomes of the patients and absence of expression of their source genes from any healthy and essential human tissues, except from immune-privileged sites. Additionally, peptides were selected as potential biomarkers if their levels in the plasma-sHLA peptidome were significantly reduced after the removal of tumor mass. The CTAs identified among the analyzed HLA peptidomes provide new opportunities for personalized immunotherapy and for early diagnosis of GBM.


Assuntos
Antígenos de Neoplasias/sangue , Neoplasias Encefálicas/sangue , Glioblastoma/sangue , Antígenos de Histocompatibilidade Classe I/sangue , Peptídeos/sangue , Proteoma/metabolismo , Alelos , Biomarcadores Tumorais/sangue , Neoplasias Encefálicas/cirurgia , Glioblastoma/cirurgia , Humanos
16.
J Med Food ; 22(10): 982-992, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31194598

RESUMO

Osteoporosis and cardiovascular disease are global health burdens, with postmenopausal women being at great risk. Dried plums/prunes (DPs) have been reported to provide bone health benefits in animal models, which is consistent with in vitro models. Data from human studies suggest that DP intake can enhance lipid metabolism, anti-inflammatory, and oxidant defense systems, which can impact cardiovascular health. We tested the hypothesis that short-term consumption of low and reasonable levels of DPs augments bone resorption and vascular function. Twenty-seven healthy, postmenopausal women were randomly assigned to consume six DPs (∼42 g) or two DPs (∼14 g) per day for 2 weeks, then a 2-week washout period and then crossed over. Serum C-telopeptide, beta-crosslinked (CTX) was used as a measure of bone resorption. Peripheral artery tonometry (PAT) was used to assess microvascular function. The pattern of changes in CTX in the second 2-week period (no change or decline) differed significantly from the pattern in the first 2 weeks (increases in both groups; F = 9.26, P = .006), suggesting a trend in CTX reduction (i.e., a decrease in bone resorption) in those consuming six DPs per day in the second phase. No effects on vascular function were noted. A significant interaction was observed for the augmentation index, a measure of arterial stiffness, between treatment and years after menopause (P = .045). The results suggest a potentially favorable impact of DPs on bone health when assessed with a short-term, crossover study design in postmenopausal women. Given the novel assessments used in this study, follow-up studies are warranted.


Assuntos
Reabsorção Óssea , Colágeno Tipo I/sangue , Frutas , Peptídeos/sangue , Prunus domestica , Rigidez Vascular , Idoso , Glicemia/análise , Pressão Sanguínea , Estudos Cross-Over , Feminino , Humanos , Lipídeos/sangue , Manometria , Pessoa de Meia-Idade , Pós-Menopausa
17.
Iran J Immunol ; 16(2): 182-189, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31182692

RESUMO

BACKGROUND: Brucella spp. are facultative intracellular pathogens that can cause chronic infections in many tissues and organs. OBJECTIVES: To investigate serum dermcidin, salusin-alpha, salusin-beta and TNF-alpha levels and their correlation with each other in patients with acute brucellosis. METHODS: From 50 patients hospitalized upon diagnosis of acute brucellosis, blood samples were collected and dermcidin, salusin-alpha, salusin-beta and TNF-alpha levels in serum samples were measured using an ELISA assay. The control group included 40 volunteers. RESULTS: Brucellosis group had significantly lower plasma dermcidin, salusin- alpha, salusin-beta levels compared to the healthy control group (respectively p=0.008, p<0.001, p<0.001). Moreover, Brucellosis group had significantly higher plasma TNF-alpha levels comparisons with the controls (p=0.002). In the examination of the correlation between TNF-alpha and dermcidin, salusin-alpha and salusin-beta in the brucellosis group, only a negative correlation was found between salusin-beta and TNF-alpha. In the control group, there was a positive and statistically significant correlation between salusin-beta and TNF-alpha. CONCLUSION: Dermcidin, salusin-alpha, and particularly salusin-beta levels are important in Brucella pathogenesis. The paradoxical correlation between TNF-alpha and salusin-beta in patients with brucellosis and control group is remarkable. However, there is a need for extensive studies conducted with more patients to further elucidate this topic.


Assuntos
Brucella/fisiologia , Brucelose/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/sangue , Peptídeos/sangue , Fator de Necrose Tumoral alfa/sangue , Doença Aguda , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transdução de Sinais
18.
Parasite ; 26: 33, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31166908

RESUMO

Cases of newly developed advanced schistosomiasis (NDAS) have occurred in areas where schistosomiasis transmission has been blocked for more than 25 years. The causes and pathogenesis of NDAS are still unknown. Diagnosis of NDAS relies on historical investigation and clinical symptoms, such as liver fibrosis, hepatic ascites and abnormal biochemical indexes in serum. It is important but difficult at this stage to develop a new tool for early screening and rapid diagnosis. In this study, serum peptides from thirty patients with NDAS and thirty healthy controls were captured with weak cation exchange magnetic beads, and subjected to MALDI-TOF mass spectrometry and ClinProTools analysis. Eleven peaks with m/z 924, 2661, 2953, 2991, 3241, 3884, 5337, 5905, 5943, 7766 and 9289 were decreased and three peaks with m/z 1945, 2082 and 4282 were increased in the NDAS group. The proteomic detection pattern (PDP) was established with 14 different peptide peaks, and its sensitivity and specificity were investigated with a blind test. The peptide mass fingerprints of sera from 50 NDAS patients and 100 healthy controls were double-blind subjected to the PDP method, and 50 patients and 92 healthy controls were classified as NDAS and healthy separately, which showed 100% sensitivity and 92% specificity. Our results showed that the PDP could be a new and useful method to detect NDAS.


Assuntos
Proteômica/métodos , Esquistossomose/diagnóstico , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Idoso , Método Duplo-Cego , Feminino , Humanos , Ácido Hialurônico/sangue , Masculino , Pessoa de Meia-Idade , Peptídeos/sangue , Reprodutibilidade dos Testes , Esquistossomose/sangue , Sensibilidade e Especificidade , gama-Glutamiltransferase/sangue
19.
Fertil Steril ; 112(2): 362-370, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31227287

RESUMO

OBJECTIVE: To study the effects of metformin treatment on bone turnover in women with polycystic ovary syndrome (PCOS), as measured by serum concentrations of bone turnover markers. DESIGN: Post hoc study of a previously conducted prospective multicenter, placebo-controlled, randomized study. SETTING: University clinic. PATIENT(S): The study cohort consisted of 74 non-obese women (body mass index < 27 kg/m2) and 44 obese women (body mass index ≥ 27 kg/m2) diagnosed with PCOS, with a mean age of 27.6 ± 4.0 (SD) years. INTERVENTION(S): Randomization to receive metformin or placebo for 3 months. MAIN OUTCOME MEASURE(S): Serum levels of bone formation marker procollagen type I amino-terminal propeptide (PINP) and bone resorption marker carboxy-terminal cross-linking telopeptide of type I collagen (CTX) at baseline and after metformin/placebo treatment. RESULT(S): Serum levels of PINP and CTX were similar between the metformin and placebo groups at baseline in the whole study population. Obese women, when compared with non-obese, had lower baseline levels of PINP and CTX. Levels of PINP and CTX were significantly reduced in the whole study population, as well as in both non-obese and obese women after 3 months of metformin treatment, whereas no significant changes were observed in the placebo group. CONCLUSION(S): Metformin treatment, when compared with placebo, was associated with reduced bone turnover, as suggested by reductions in markers of bone formation and resorption, leading to slower bone remodeling in premenopausal women with PCOS. CLINICAL TRIAL REGISTRATION NUMBER: NCT00994812.


Assuntos
Biomarcadores/sangue , Remodelação Óssea/efeitos dos fármacos , Metformina/uso terapêutico , Síndrome do Ovário Policístico/tratamento farmacológico , Adulto , Densidade Óssea/efeitos dos fármacos , Colágeno Tipo I/sangue , Feminino , Humanos , Metformina/farmacologia , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Placebos , Síndrome do Ovário Policístico/sangue , Pró-Colágeno/sangue , Estudos Retrospectivos , Adulto Jovem
20.
Osteoporos Int ; 30(9): 1755-1765, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31227885

RESUMO

The relationships of osteocalcin (OC) and C-telopeptide of type I collagen (CTX) with long-term incidence of hip fracture were examined in 1680 post-menopausal women from a population-based study. CTX, but not OC, levels were associated with incident hip fracture in these participants, a relationship characterized by an inverted U-shape. INTRODUCTION: We sought to investigate the relationships of OC, a marker of bone formation, and CTX, a marker of bone resorption, with long-term incidence of hip fracture in older women. METHODS: We included 1680 women from the population-based Cardiovascular Health Study (mean [SD] age 74.5 [5.0] years). The longitudinal association of both markers with incidence of hip fracture was examined using multivariable Cox models. RESULTS: During a median follow-up of 12.3 years, 288 incident hip fractures occurred. Linear spline analysis did not demonstrate an association between OC levels and incident hip fracture. By contrast, increasing levels of CTX up to the middle-upper range were associated with a significantly greater risk of hip fracture (HR = 1.52 per SD increment, 95% CI = 1.10-2.09), while further increases were associated with a marginally non-significant lower risk (HR = 0.80 per SD increment, 95% CI = 0.63-1.01), after full adjustment for potential confounders. In analyses of quartiles, CTX exhibited a similar inverted U-shaped relationship with incident fracture after adjustment, with a significant association observed only for the comparison of quartile 3 to quartile 1 (HR = 1.63, 95% CI = 1.10-2.43). In a subset with available measures, both OC and CTX were inversely associated with bone mineral density of the hip. CONCLUSION: CTX, but not OC, levels were associated with incident hip fracture in post-menopausal women, a relationship characterized by an inverted U-shape. These findings highlight the complex relationship of bone turnover markers with hip fracture risk.


Assuntos
Remodelação Óssea/fisiologia , Fraturas do Quadril/fisiopatologia , Osteoporose Pós-Menopausa/fisiopatologia , Fraturas por Osteoporose/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Densidade Óssea/fisiologia , Colágeno Tipo I/sangue , Feminino , Seguimentos , Fraturas do Quadril/sangue , Fraturas do Quadril/epidemiologia , Humanos , Incidência , Estilo de Vida , Osteocalcina/sangue , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/epidemiologia , Fraturas por Osteoporose/sangue , Fraturas por Osteoporose/epidemiologia , Peptídeos/sangue , Desempenho Físico Funcional , Medição de Risco/métodos , Estados Unidos/epidemiologia
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