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1.
Phys Rev Lett ; 124(6): 062501, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32109090

RESUMO

The low-lying energy spectrum of the extremely neutron-deficient self-conjugate (N=Z) nuclide _{44}^{88}Ru_{44} has been measured using the combination of the Advanced Gamma Tracking Array (AGATA) spectrometer, the NEDA and Neutron Wall neutron detector arrays, and the DIAMANT charged particle detector array. Excited states in ^{88}Ru were populated via the ^{54}Fe(^{36}Ar,2nγ)^{88}Ru^{*} fusion-evaporation reaction at the Grand Accélérateur National d'Ions Lourds (GANIL) accelerator complex. The observed γ-ray cascade is assigned to ^{88}Ru using clean prompt γ-γ-2-neutron coincidences in anticoincidence with the detection of charged particles, confirming and extending the previously assigned sequence of low-lying excited states. It is consistent with a moderately deformed rotating system exhibiting a band crossing at a rotational frequency that is significantly higher than standard theoretical predictions with isovector pairing, as well as observations in neighboring N>Z nuclides. The direct observation of such a "delayed" rotational alignment in a deformed N=Z nucleus is in agreement with theoretical predictions related to the presence of strong isoscalar neutron-proton pair correlations.

2.
BMC Cancer ; 19(1): 786, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31391014

RESUMO

BACKGROUND: Data indicate that primary cutaneous melanomas are characterized by clonal heterogeneity associated with oncogenic drivers. Less data are available on the clonal changes occurring during melanoma progression. We therefore wished to analyse these changes in skin melanomas in common sites of visceral metastases as compared to the primary tumor. METHODS: An autopsy cohort of 50 patients with BRAF- and NRAS-mutant cutaneous metastatic melanomas including 139 visceral metastases was analysed for mutant allele fractions (MAF), determined by pyrosequencing and corrected for tumor/normal ratio. MAF levels were also classified as high (> 40%), medium (15-40%) or low (< 15%). RESULTS: Contrary to NRAS mutant cases, in BRAF-mutant melanomas MAFs were found to be significantly increased in visceral metastases compared to the primary due to the significantly higher levels in lung-, adrenal gland-, intestinal- and kidney metastases. The incidence of the three MAF variants in BRAF-mutant primaries was similar, whereas the high MAF cases were found to be increased in metastases. On the other hand, medium MAF levels were more common in case of NRAS-mutant tumors. Only 31.3% of BRAF mutant- and 50% of NRAS mutant cases maintained the MAF profile of the primary in metastasis. In the majority of multiple metastatic tumors, (BRAF:71.8%, NRAS:75%) metastases were relatively homogeneous regarding MAF. However, in 6/32(18.7%) of BRAF mutant cases low MAF primaries switched to high MAF in metastases. In heterogeneous BRAF mutant metastatic cases low to high or high to low MAF conversions occurred in a further 4/32(12.5%) cases in individual metastases as compared to the primary tumors. At lower frequency, in NRAS mutant tumor such changes also observed (2/12,16.7%). CONCLUSION: We provided evidence for the selection of BRAF-mutant melanoma cells during metastatic progression to the lung, intestine, adrenal gland and kidney. Our findings suggest that in visceral metastases of malignant melanoma BRAF- or NRAS-MAFs are rather heterogeneous and cannot be predicted from data of the primary tumor. These data may have clinical significance when using targeted therapies.

3.
BMC Cancer ; 19(1): 853, 2019 Aug 29.
Artigo em Inglês | MEDLINE | ID: mdl-31464610

RESUMO

Following publication of the original article [1], the authors reported the family name of the second author was incorrectly published.

5.
Phys Rev Lett ; 122(6): 062501, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30822069

RESUMO

New rotational bands built on the ν(h_{11/2}) configuration have been identified in ^{105}Pd. Two bands built on this configuration show the characteristics of transverse wobbling: the ΔI=1 transitions between them have a predominant E2 component and the wobbling energy decreases with increasing spin. The properties of the observed wobbling bands are in good agreement with theoretical results obtained using constrained triaxial covariant density functional theory and quantum particle rotor model calculations. This provides the first experimental evidence for transverse wobbling bands based on a one-neutron configuration, and also represents the first observation of wobbling motion in the A∼100 mass region.

6.
Phys Rev Lett ; 121(3): 032502, 2018 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-30085775

RESUMO

Energy differences between analogue states in the T=1/2 ^{23}Mg-^{23}Na mirror nuclei have been measured along the rotational yrast bands. This allows us to search for effects arising from isospin-symmetry-breaking interactions (ISB) and/or shape changes. Data are interpreted in the shell model framework following the method successfully applied to nuclei in the f_{7/2} shell. It is shown that the introduction of a schematic ISB interaction of the same type of that used in the f_{7/2} shell is needed to reproduce the data. An alternative novel description, applied here for the first time, relies on the use of an effective interaction deduced from a realistic charge-dependent chiral nucleon-nucleon potential. This analysis provides two important results: (i) The mirror energy differences give direct insight into the nuclear skin; (ii) the skin changes along the rotational bands are strongly correlated with the difference between the neutron and proton occupations of the s_{1/2} "halo" orbit.

7.
Ann Oncol ; 29(9): 1948-1954, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29917049

RESUMO

Background: Based on its mechanism of action, PARP inhibitor therapy is expected to benefit mainly tumor cases with homologous recombination deficiency (HRD). Therefore, identification of tumor types with increased HRD is important for the optimal use of this class of therapeutic agents. HRD levels can be estimated using various mutational signatures from next generation sequencing data and we used this approach to determine whether breast cancer brain metastases show altered levels of HRD scores relative to their corresponding primary tumor. Patients and methods: We used a previously published next generation sequencing dataset of 21 matched primary breast cancer/brain metastasis pairs to derive the various mutational signatures/HRD scores strongly associated with HRD. We also carried out the myChoice HRD analysis on an independent cohort of 17 breast cancer patients with matched primary/brain metastasis pairs. Results: All of the mutational signatures indicative of HRD showed a significant increase in the brain metastases relative to their matched primary tumor in the previously published whole exome sequencing dataset. In the independent validation cohort, the myChoice HRD assay showed an increased level in 87.5% of the brain metastases relative to the primary tumor, with 56% of brain metastases being HRD positive according to the myChoice criteria. Conclusions: The consistent observation that brain metastases of breast cancer tend to have higher HRD measures may raise the possibility that brain metastases may be more sensitive to PARP inhibitor treatment. This observation warrants further investigation to assess whether this increase is common to other metastatic sites as well, and whether clinical trials should adjust their strategy in the application of HRD measures for the prioritization of patients for PARP inhibitor therapy.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias Encefálicas/genética , Neoplasias da Mama/genética , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Reparo de DNA por Recombinação , Adulto , Idoso , Encéfalo/patologia , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/secundário , Mama/patologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Análise Mutacional de DNA , Conjuntos de Dados como Assunto , Resistencia a Medicamentos Antineoplásicos/genética , Feminino , Humanos , Pessoa de Meia-Idade , Mutação , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico
8.
Cancer Metastasis Rev ; 35(1): 93-107, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26970965

RESUMO

Malignant melanoma of the skin is the most aggressive human cancer given that a primary tumor a few millimeters in diameter frequently has full metastatic competence. In view of that, revealing the genetic background of this potential may also help to better understand tumor dissemination in general. Genomic analyses have established the molecular classification of melanoma based on the most frequent driver oncogenic mutations (BRAF, NRAS, KIT) and have also revealed a long list of rare events, including mutations and amplifications as well as genetic microheterogeneity. At the moment, it is unclear whether any of these rare events have role in the metastasis initiation process since the major drivers do not have such a role. During lymphatic and hematogenous dissemination, the clonal selection process is evidently reflected by differences in oncogenic drivers in the metastases versus the primary tumor. Clonal selection is also evident during lymphatic progression, though the genetic background of this immunoselection is less clear. Genomic analyses of metastases identified further genetic alterations, some of which may correspond to metastasis maintenance genes. The natural genetic progression of melanoma can be modified by targeted (BRAF or MEK inhibitor) or immunotherapies. Some of the rare events in primary tumors may result in primary resistance, while further new genetic lesions develop during the acquired resistance to both targeted and immunotherapies. Only a few genetic lesions of the primary tumor are constant during natural or therapy-modulated progression. EGFR4 and NMDAR2 mutations, MITF and MET amplifications and PTEN loss can be considered as metastasis drivers. Furthermore, BRAF and MITF amplifications as well as PTEN loss are also responsible for resistance to targeted therapies, whereas NRAS mutation is the only founder genetic lesion showing any association with sensitivity to immunotherapies. Unfortunately, there are hardly any data on the possible organ-specific metastatic drivers in melanoma. These observations suggest that clinical management of melanoma patients must rely on the genetic analysis of the metastatic lesions to be able to monitor progression-associated changes and to personalize therapies.


Assuntos
Carcinogênese , Resistencia a Medicamentos Antineoplásicos/genética , Melanoma/genética , Receptores ErbB/genética , Humanos , Melanoma/patologia , Fator de Transcrição Associado à Microftalmia/genética , Mutação , PTEN Fosfo-Hidrolase/genética , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas c-met/genética , Receptores de N-Metil-D-Aspartato/genética
9.
Phys Rev Lett ; 116(4): 042501, 2016 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-26871324

RESUMO

Electron-positron angular correlations were measured for the isovector magnetic dipole 17.6 MeV (J^{π}=1^{+}, T=1) state→ground state (J^{π}=0^{+}, T=0) and the isoscalar magnetic dipole 18.15 MeV (J^{π}=1^{+}, T=0) state→ground state transitions in ^{8}Be. Significant enhancement relative to the internal pair creation was observed at large angles in the angular correlation for the isoscalar transition with a confidence level of >5σ. This observation could possibly be due to nuclear reaction interference effects or might indicate that, in an intermediate step, a neutral isoscalar particle with a mass of 16.70±0.35(stat)±0.5(syst) MeV/c^{2} and J^{π}=1^{+} was created.

10.
BMC Infect Dis ; 15: 530, 2015 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-26578348

RESUMO

BACKGROUND: The local immune responses to chronic echinococcal infections in various organs are largely unknown. Since the liver is the most frequently involved organ in such infections in human we aimed to characterize the inflammatory as well as immune cell infiltrate around hydatid cysts in the liver and compared to common inflammatory processes of the liver. METHOD: Surgical samples from the liver of 21 cystic echinococcosis (CE) patients were studied and the distribution of different types of inflammatory and immune cells were determined by immunohistochemistry. Furthermore, expression levels of costimulatory CTLA4, CD28, CD80 and CD86 molecules were measured at RNA level by PCR. Liver biopsy samples from patients with steatohepatitis (SH, n = 11) and chronic hepatitis (CH, n = 11) were used as non-inflammatory and chronic inflammatory controls, respectively. The composition and density of the inflammatory and immune cell infiltrates have been compared by using morphometry. RESULTS: CD3+ T cells predominated the inflammatory infiltrate in all pathological processes, while in CE samples CD20+ B cells, in CH samples CD68+ macrophages were also frequent. Both myeloperoxidase (MPO) + leukocytes and CD68+ macrophages were found to be significantly decreased in CE as compared to either SH or CH samples. Concerning T cell subtypes, only CD8+ T cells were found to be significantly decreased in SH samples. CD1a + dendritic cells were almost completely missing from CE biopsies unlike in any other sample types. There were no differences detected in the mRNA expression of costimulatory molecules except decreased expression of CD28 in CE samples. CONCLUSION: In the hydatid lesions of the liver of chronic echinococcal infections T cell-mediated immunity seems to be impaired as compared to other types of chronic inflammatory processes, suggesting an immunosuppressive role for Echinococcus granulosus, which deserve further attentions.


Assuntos
Antígenos CD/metabolismo , Equinococose Hepática/patologia , Echinococcus granulosus/patogenicidade , Adolescente , Adulto , Idoso , Animais , Antígenos CD/genética , Antígenos CD/imunologia , Antígeno B7-2/metabolismo , Antígeno CTLA-4 , Criança , Pré-Escolar , Células Dendríticas/imunologia , Células Dendríticas/patologia , Equinococose Hepática/genética , Equinococose Hepática/metabolismo , Feminino , Humanos , Imunidade Celular/imunologia , Imuno-Histoquímica , Macrófagos/imunologia , Macrófagos/patologia , Masculino , Pessoa de Meia-Idade , Linfócitos T/imunologia , Linfócitos T/patologia , Adulto Jovem
11.
Magy Onkol ; 59(3): 259-66, 2015 Sep.
Artigo em Húngaro | MEDLINE | ID: mdl-26339915

RESUMO

Development of the target therapies of lung cancer was a rapid process which fundamentally changed the pathological diagnosis as well. Furthermore, molecular pathology became essential part of the routine diagnostics of lung cancer. These changes generated several practical problems and in underdeveloped countries or in those with reimbursement problems have been combined with further challenges. The central and eastern region of Europe are characterized by similar problems in this respect which promoted the foundation of NSCLC Working Group to provide up to date protocols or guidelines. This present paper is a summary of the molecular pathology and target therapy guidelines written with the notion that it has to be upgraded continuously according to the development of the field.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Quinase do Linfoma Anaplásico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Consenso , Receptores ErbB/genética , Europa (Continente) , Rearranjo Gênico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Terapia de Alvo Molecular/métodos , Mutação , Patologia Molecular/métodos , Equipe de Assistência ao Paciente , Guias de Prática Clínica como Assunto , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Receptores Proteína Tirosina Quinases/genética , Proteínas ras/genética
12.
Phys Rev Lett ; 113(3): 032501, 2014 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-25083635

RESUMO

Three sets of chiral doublet band structures have been identified in the ^{103}Rh nucleus. The properties of the observed chiral doublet bands are in good agreement with theoretical results obtained using constrained covariant density functional theory and particle rotor model calculations. Two of them belong to an identical configuration and provide the first experimental evidence for a novel type of multiple chiral doublets, where an "excited" chiral doublet of a configuration is seen together with the "yrast" one. This observation shows that the chiral geometry in nuclei can be robust against the increase of the intrinsic excitation energy.

13.
Am J Transplant ; 14(4): 966-71, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24712333

RESUMO

Lung transplantation through controlled donation after circulatory death (cDCD) has slowly gained universal acceptance with reports of equivalent outcomes to those through donation after brain death. In contrast, uncontrolled DCD (uDCD) lung use is controversial and requires ethical, legal and medical complexities to be addressed in a limited time. Consequently, uDCD lung use has not previously been reported in the United States. Despite these potential barriers, we present a case of a patient with multiple gunshot wounds to the head and the body who was unsuccessfully resuscitated and ultimately became an uDCD donor. A cytomegalovirus positive recipient who had previously consented for CDC high-risk, DCD and participation in the NOVEL trial was transplanted from this uDCD donor, following 3 h of ex vivo lung perfusion. The postoperative course was uneventful, and the recipient was discharged home on day 9. While this case represents a "best-case scenario," it illustrates a method for potential expansion of the lung allograft pool through uDCD after unsuccessful resuscitation in hospitalized patients.


Assuntos
Morte , Seleção do Doador , Transplante de Pulmão , Doadores de Tecidos , Obtenção de Tecidos e Órgãos/métodos , Adulto , Sobrevivência de Enxerto , Humanos , Masculino , Prognóstico , Obtenção de Tecidos e Órgãos/ética , Obtenção de Tecidos e Órgãos/legislação & jurisprudência
14.
Cancer Metastasis Rev ; 32(3-4): 493-9, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23636347

RESUMO

Metastasis of human cancer is an organ-selective process that is determined by anatomical and biological factors as well as by specific microenvironmental properties. Dissemination of visceral malignancies to the skin is rather rare and usually occurs in a later stage of the disease. Using statistical approaches, both positive (renal and lung cancers) and negative (pancreatic and liver cancers) organ preferences can be identified in a variety of cancers. While certain cancer types are characterized by random distribution for skin metastasis (liver cancer), a number of cancers demonstrate a colonization preference to the region of origin: lung cancer to the supradiaphragmatic (mostly chest) and colorectal cancers to the infradiaphragmatic (abdominal) skin regions. In certain cases, however, skin metastasis develops more frequently at specific distant locations, as evidenced by the dissemination of renal cancer at the head and neck region. These findings are clinically relevant and useful especially in patients where skin metastasis is the first indication of a malignancy. Nevertheless, it is a strong argument for the predominant role of microenvironmental factors in cancer dissemination. On the other hand, skin metastases of visceral cancers provide a unique model to analyze the pathomechanisms determining organ selectivity, including the organ-specific vascularization, the dermatome-specific innervation, or immunological and developmental factors.


Assuntos
Neoplasias/patologia , Neoplasias Cutâneas/diagnóstico , Neoplasias Cutâneas/secundário , Humanos , Neoplasias/diagnóstico , Neovascularização Patológica , Especificidade de Órgãos , Prevalência , Neoplasias Cutâneas/epidemiologia
15.
Cancer Lett ; 335(2): 495-501, 2013 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-23523613

RESUMO

Nearly 30% of prostate cancer (PCa) patients treated with potentially curative doses relapse at the sites of irradiation. How some tumor cells acquire radioresistance is poorly understood. The platelet-type 12-lipoxygenases (12-LOX)-mediated arachidonic acid metabolism is important in PCa progression. Here we show that 12-LOX confers radioresistance upon PCa cells. Treatment with 12-LOX inhibitors baicalein or BMD122 sensitizes PCa cells to radiation, without radiosensitizing normal cells. 12-LOX inhibitors and radiation, when combined, have super additive or synergistic inhibitory effects on the colony formation of both androgen-dependent LNCaP and androgen-independent PC-3 PCa cells. In vivo, the combination therapy significantly reduced tumor growth.


Assuntos
Araquidonato 12-Lipoxigenase/metabolismo , Ácido Araquidônico/metabolismo , Flavanonas/farmacologia , Inibidores de Lipoxigenase/farmacologia , Neoplasias da Próstata/radioterapia , Animais , Apoptose/efeitos da radiação , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Camundongos , Camundongos SCID , Tolerância a Radiação
16.
Pathol Oncol Res ; 19(3): 515-20, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23468362

RESUMO

Skin metastatization of internal cancers are rare and a few studies are available analyzing its clinicopathological features. The reported incidence of skin metastasis is influenced by two factors: the relative proportion of cancers covered by skin in the various cohorts and the large differences in the prevalences of various cancer types. Futhermore, the anatomical distribution of skin metastases of various cancer types is aslo not well known. Therefore we have collected a skin metastasis cohort of biopsy and authopsy cases (n = 80) from the archive of our department and analysed its clinicopathologic features. The adjusted skin metastasis prevalence data of various inner cancers indicated that kidney-, lung- and colorectal cancers have a strong positive preference for skin metastatisation while pancreatic cancer has a negative one. We have provided evidences that lower gastrointestinal- and genitourinary cancers preferred infradiaphragmatic skin regions unlike upper gastrointestinal cancers while lung- and kidney cancers preferred supradiaphragmatic regions. We have also detected that ventral skin regional metastasis is slightly more prevalent irrespective of the cancer type. Our study provide the first statistical data for the variations in skin preference of metastatisation among various cancer types as well as for the significant variations in their regional distributions.


Assuntos
Neoplasias/patologia , Neoplasias Cutâneas/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica
17.
Brain Res Bull ; 90: 66-71, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22995282

RESUMO

Since the discovery of opioid receptor dimers their possible roles in opioid actions were intensively investigated. Here we suggest a mechanism that may involve the µ-δ opioid heterodimers. The exact role of δ opioid receptors in antinociception and in the development of opioid tolerance is still unclear. While receptor up-regulation can be observed during the development of opioid tolerance no µ receptor down-regulation could be detected within five days. In our present work we investigated how the selective δ opioid receptor agonists and antagonists influence the antinociceptive effect of the selective µ receptor agonist DAMGO in naïve and morphine-tolerant mice. We treated male NMRI mice with 200 µmol/kg subcutaneous (s.c.) morphine twice daily for three days. On the fourth day we measured the antinociceptive effect of DAMGO alone and combined with delta ligands: DPDPE, deltorphin II (agonists), TIPP and TICPψ (antagonists), respectively, administered intrathecally (i.t.) in mouse tail-flick test. In naive control mice none of the δ ligands caused significant changes in the antinociceptive action of DAMGO. The treatment with s.c. morphine resulted in approximately four-fold tolerance to i.t. DAMGO, i.e. the ED50 value of DAMGO was four times as high as in naive mice. 500 and 1000 pmol/mouse of the δ1 selective agonist DPDPE enhanced the tolerance to DAMGO while 1000 pmol/mouse of the δ2 selective agonist deltorphin II did not influence the degree of tolerance. However, both δ antagonists TIPP and TICPψ potentiated the antinociceptive effect of i.t. DAMGO, thus they restored the potency of DAMGO to the control level. The inhibitory action of DPDPE against the antinociceptive effect of DAMGO could be antagonized by TIPP and TICPψ. We hypothesize that during the development of morphine tolerance the formation of µÎ´ heterodimers may contribute to the spinal opioid tolerance. δ ligands may affect the dimer formation differently. Those, like DPDPE may facilitate the dimer formation hence inhibit the antinociceptive effect of DAMGO by causing virtual µ receptor down-regulation. Ligands that do not affect the dimer formation do not influence antinociception either but ligands with the presumed capability of disconnecting the dimers may decrease the spinal tolerance to DAMGO.


Assuntos
Analgésicos Opioides/farmacologia , Tolerância a Medicamentos/fisiologia , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Morfina/farmacologia , Receptores Opioides delta/metabolismo , Medula Espinal/metabolismo , Animais , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Vias de Administração de Medicamentos , Esquema de Medicação , Interações Medicamentosas , Ligantes , Masculino , Camundongos , Medição da Dor/efeitos dos fármacos , Somatostatina/análogos & derivados , Somatostatina/farmacologia , Medula Espinal/efeitos dos fármacos , Ducto Deferente/efeitos dos fármacos , Ducto Deferente/patologia
18.
Curr Med Chem ; 19(27): 4699-707, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22934777

RESUMO

The aims of this study were to synthesize 14-O-Methylmorphine-6-O-sulfate (14-O-MeM6SU) and examine its opioid properties (potency, affinity, efficacy) in receptor ligand binding and isolated tissues (mouse vas deferens, MVD and rat vas deferens, RVD bioassays). The results were then compared to the parent compounds morphine-6-O-sulfate (M6SU) and morphine, as well as the �- opioid receptor (MOR) selective agonist peptide [D-Ala2,N-Me-Phe4,Gly-ol5]enkephalin (DAMGO). An additional objective was to compare the effect of subcutaneously (s.c.) or intracerebroventricularly (i.c.v.) administered 14-O-MeM6SU, M6SU and morphine in thermal nociception, rat tail-flick (RTF) test. In MVD, the EC50 (nM) value was 4.38 for 14-O-MeM6SU, 102.81 for M6SU, 346.63 for morphine and 238.47 for DAMGO. The effect of 14-O-MeM6SU and DAMGO was antagonized by naloxone (NAL) with Ke value 1-2.00 nM. The Emax values (%) were 99.10, 36.87, 42.51 and 96.99 for 14-O-MeM6SU, M6SU, morphine and DAMGO, respectively. In RVD 14-O-MeM6SU and DAMGO but not M6SU or morphine showed agonist activity. In binding experiments the affinity of 14-OMeM6SU, M6SU, morphine and DAMGO for MOR was 1.12, 11.48, 4.37 and 3.24 nM, respectively. The selectivity of 14-O-MeM6SU was κ/µ= 269 and δ/µ= 9. In G-protein activation experiments, 14-O-MeM6SU and DAMGO showed higher Emax values than M6SU or morphine. S.c. or i.c.v-injected 14-O-MeM6SU, M6SU and morphine produced a dose and time-dependent increase in RTF response latency. 14-O-MeM6SU was the most potent. Our results showed that introduction of 14-O-Me in M6SU increased the binding affinity, agonist potency, and most importantly, the intrinsic efficacy (Emax).


Assuntos
Codeína/análogos & derivados , Ligantes , Receptores Opioides mu/agonistas , Analgésicos/química , Analgésicos/farmacologia , Animais , Codeína/síntese química , Codeína/química , Codeína/farmacologia , Ala(2)-MePhe(4)-Gly(5)-Encefalina/farmacologia , Cobaias , Técnicas In Vitro , Cinética , Masculino , Camundongos , Morfina/farmacologia , Derivados da Morfina/farmacologia , Contração Muscular/efeitos dos fármacos , Ligação Proteica , Ratos , Ratos Wistar , Receptores Opioides mu/metabolismo , Ducto Deferente/efeitos dos fármacos , Ducto Deferente/fisiologia
19.
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
20.
Acta Physiol Hung ; 99(1): 1-17, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22425803

RESUMO

Glycine is a mandatory positive allosteric modulator of N-methyl-D-aspartate (NMDA)-type ionotropic glutamate receptors in the central nervous system. Elevation of glycine concentrations by inhibition of its reuptake in the vicinity of NMDA receptors may positively influence receptor functions as glycine B binding site on NR1 receptor subunit is not saturated in physiological conditions. Synaptic and extrasynaptic concentrations of glycine are regulated by its type-1 glycine transporter, which is primarily expressed in astroglial and glutamatergic cell membranes. Alteration of synaptic glycine levels may have importance in the treatment of various forms of endogenous psychosis characterized by hypofunctional NMDA receptors. Several lines of evidence indicate that impaired NMDA receptor-mediated glutamatergic neurotransmission is involved in development of the negative (and partly the positive) symptoms and the cognitive deficit in schizophrenia. Inhibitors of glycine transporter type-1 may represent a newly developed therapeutic intervention in treatment of this mental illness. We have synthesized a novel series of N-substituted sarcosines, analogues of the glycine transporter-1 inhibitor NFPS (N-[3-(4'-fluorophenyl)-3-(4'-phenylphenoxy)-propyl]sarcosine). Of the pyridazinone-containing compounds, SzV-1997 was found to be a potent glycine transporter-1 inhibitor in rat brain synaptosomes and it markedly increased extracellular glycine concentrations in conscious rat striatum. SzV-1997 did not exhibit toxic symptoms such as hyperlocomotion, restless movements, respiratory depression, and lethality, characteristic for NFPS. Besides pyridazinone-based, sarcosine-containing glycine transporter-1 inhibitors, a series of substrate-type amino acid inhibitors was investigated in order to obtain better insight into the ligand-binding characteristics of the substrate binding cavity of the transporter.


Assuntos
Química Encefálica/fisiologia , Proteínas da Membrana Plasmática de Transporte de Glicina/antagonistas & inibidores , Proteínas da Membrana Plasmática de Transporte de Glicina/fisiologia , Glicina/fisiologia , Receptores de N-Metil-D-Aspartato/fisiologia , Animais , Proteínas da Membrana Plasmática de Transporte de Glicina/química , Humanos , Sarcosina/farmacologia
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