RESUMO
OBJECTIVE: Epidermal growth factor receptors (EGFR) mutation status is crucial for the prediction of a tumour response to treatment with EGFR tyrosine kinase (EGFR-TK) inhibitors. The aim of the study was to establish a protocol for the detection of EGFR-activating somatic mutations on cytological samples collected using a standard bronchoscopy procedure and to determine the frequency of EGFR mutations among pre-selected Croatian patients with non-small cell lung cancer (NSCLC) of an adenocarcinoma histological subtype. METHODS: A total of 177 cytological samples were collected from the patients diagnosed with NSCLC. DNA was isolated from the cytological material recovered from the fixed and stained slides. EGFR mutations were analysed using the polymerase chain reaction (PCR)- mediated Sanger sequencing method. RESULTS: Out of 177 collected samples, EGFR mutation analyses were successfully performed on 167 samples (94.4%); 77 (46.1%) of these were from male and 90 (53.9%) from female patients. EGFR mutations/deletions were found in 33 (19.8%) of the tested patients; exon 19 deletions in 17 (10.2%) and point mutations of exon 21 in 16 (9.6%) patients. CONCLUSION: The PCR-mediated Sanger sequencing method was found to be reproducible and reliable. Cytological samples can be used successfully to determine the EGFR mutation status in NSCLC patients providing information for targeted therapy at an early stage of the disease.
Assuntos
Adenocarcinoma/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Citodiagnóstico , Receptores ErbB/genética , Neoplasias Pulmonares/diagnóstico , Adenocarcinoma/genética , Adenocarcinoma/patologia , Adenocarcinoma de Pulmão , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha Fina , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , MutaçãoRESUMO
Renal cell carcinoma (RCC) is the most common solid kidney tumor representing 2-3% of all cancers, with the highest frequency occurring in Western countries. There was a worldwide and European annual increase in incidence of approximately 2% although incidence has been stabilized in last few years. One third of the patients already have metastases in the time of the diagnosis with poor prognosis because RCC are radio and chemoresistant. The prognostic value of EGFR over-expression in RCC is a controversial issue that could be explained by different histological types of study tumors and non-standardized criteria for evaluation of expression. Recent evidences points to a new mode of EGFR signaling pathway in which activated EGFR undergoes nuclear translocalization and then, as transcription factor, mediates gene expression and other cellular events required for highly proliferating activities. According to our observations, the membranous expression of EGFR associates with high nuclear grade and poor differentiated tumors. On the other hand, nuclear EGFR expression was high in low nuclear graded and well differentiated tumors with good prognosis. We hypothesize that this mode of EGFR signaling characterizes still controlled proliferation retained in well differentiated RCC with Furhman nuclear grade I or II.
Assuntos
Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Núcleo Celular/metabolismo , Receptores ErbB/metabolismo , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Biomarcadores Tumorais/metabolismo , Diferenciação Celular , Proliferação de Células , Simulação por Computador , Humanos , Modelos Biológicos , Invasividade NeoplásicaRESUMO
AIM AND BACKGROUND: Epidermal growth factor receptor (EGFR) is a receptor tyrosine kinase involved in many important aspects of cell biology that are related to tumorigenesis. There are opposite evidences of the role of EGFR in renal cancer and the outcome of EGFR-targeted therapies, suggesting the complexity of EGFR signaling pathways. In vitro, osteopontin (OPN) and nuclear factor kappa B (NF-κB) are thought to be involved in specific ligand-independent EGFR activation that could have a role in resistance to EGFR mAb therapy. Aim of this study was to analyze the relationship between EGFR and OPN at the protein and mRNA level, as well as their relation to NF-κB in clear cell renal cell carcinoma (CCRCC). MATERIALS AND METHODS: Expression of EGFR, OPN, and p65 NF-κB protein was analyzed using immunohistochemistry and compared mutually in 88 CCRCC samples. Expression of EGFR and OPN mRNAs was analyzed using quantitative Real-time PCR in 22 CCRCC samples and compared mutually and with NF-κB protein expression. RESULTS: Epidermal growth factor receptor mRNA level was higher in CCRCC samples in comparison with normal renal tissue (p = 0.012) and was associated with high OPN mRNA level, and with NF-κB activation (p < 0.001 and p = 0.045, respectively). Immunohistochemical staining showed the inverse association; high EGFR protein expression was related with low OPN and NF-κB protein expression (p < 0.001 and p = 0.047, respectively). CONCLUSION: Epidermal growth factor receptor gene is upregulated in CRCC and associated with OPN gene expression and NF-kB signaling. The inverse relation between OPN and EGFR at the protein level could probably reflect dynamic changes that EGFR undergoes following activation.
Assuntos
Carcinoma de Células Renais/genética , Receptores ErbB/genética , Neoplasias Renais/genética , NF-kappa B/metabolismo , Osteopontina/genética , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Receptores ErbB/metabolismo , Humanos , Imuno-Histoquímica , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , NF-kappa B/genética , Osteopontina/metabolismo , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais , Regulação para CimaRESUMO
Alloimmune neonatal neutropenia (ANN) is a rare but potentially life-threatening disorder of neonates. Demonstration of alloantibodies against granulocyte-specific antigens shared by neonatal and paternal granulocytes in the maternal serum is essential in the diagnosis of ANN. In contrast to granulocyte-specific alloantibodies, the significance of human leucocyte antigen (HLA) class I antibodies for ANN is still a matter of debate. We report on a case of severe isolated and prolonged neutropenia due to anti-HLA B49 alloimmunization only. Immediately after birth, severe, isolated neutropenia was observed and lasted for up to 2 months. Results of serologic testing showed only anti-HLA B49 antibodies in the maternal and neonate's sera. HLA typing showed HLA class I (B49) incompatibility between the mother and the child. Granulocyte-specific antibodies were not detected. Adsorption of the maternal serum with HLA B49-bearing platelets removed serum reactivity with paternal neutrophils. Our results support the idea that certain HLA class I antibodies can induce ANN.
Assuntos
Granulócitos/imunologia , Antígenos HLA-B/imunologia , Isoanticorpos/imunologia , Neutropenia/congênito , Adulto , Feminino , Genótipo , Antígenos HLA-B/genética , Teste de Histocompatibilidade , Humanos , Imunização , Recém-Nascido , Isoanticorpos/sangue , Masculino , Troca Materno-Fetal , Neutropenia/imunologia , GravidezRESUMO
We report the case of serologically proven HPA-1a NATP. The child was born after uneventful 4th pregnancy. Immediately after birth generalized petechiae and signs of gastrointestinal bleeding were present. Isolated thrombocytopenia with the platelet number of 29 x 10(9)/L was observed. Serological investigation (PSIFT and MAIPA) showed high titre anti-HPA-1a antibody and low titre anti-HLA antibody in mother's sera. Mother's platelets were HPA-1a negative and she was HLA DR 52 positive. Father's platelets were HPA-1a positive. Cross-match between mother's sera and father's platelets was positive. 24 hours after the introduction of corticosteroid therapy platelet number increased to 73 x 10(9)/L and 48 hours later to 155 x 10(9)/L. The child was treated by corticosteroids because the NATP was severe and antigen negative platelets (mother or donor) or IVGG were not available. According to data from the literature the efficiency of corticosteroid therapy in NATP is questionable, but in this case it provided sufficient increase of platelet number with the stop of newborn bleeding.
Assuntos
Antígenos de Plaquetas Humanas/imunologia , Isoanticorpos/análise , Púrpura Trombocitopênica Idiopática/congênito , Feminino , Humanos , Recém-Nascido , Integrina beta3 , Masculino , Gravidez , Púrpura Trombocitopênica Idiopática/imunologia , Púrpura Trombocitopênica Idiopática/terapiaRESUMO
AIM: To detect the expression of genes encoding tyrosinase, gp100, MART-1/Melan A, and tyrosinase-related protein-2 (TRP-2) in peripheral blood of melanoma patients by reverse transcription-polymerase chain reaction (RT-PCR). METHODS: Nineteen peripheral blood samples were obtained from 17 melanoma patients. When tested, 15 of them presented with clinically detectable metastatic disease. Samples of peripheral blood (7 mL) were collected from each patient into vacutainer cell preparation tubes. Mononuclear cells were isolated, total cellular RNA extracted, and then used as a template for reverse transcription to complementary DNA (cDNA). The cDNA was thereafter assayed by PCR for the expression of melanocyte-associated transcripts of tyrosinase, gp100, MART1/Melan-A, and TRP-2 genes. RESULTS: Gp100 gene expression was detected in 13 out of 19 samples. In 4 of them, TRP-2 gene expression was also detectable. Expression of tyrosinase and Melan-A/MART-1 genes could not be observed. Interestingly, gp100 and TRP-2 gene transcripts were detected in patients having recurrent and/or metastatic disease at the time of testing. CONCLUSION: The results we obtained support the use of RT-PCR assay for indirect detection of melanoma cells in peripheral blood of melanoma patients. As the transcripts for the tyrosinase gene and MART-1/Melan A gene were not detected, additional optimization experiments of RT-PCR assay are required.
Assuntos
Melanoma/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Neoplasias Cutâneas/genética , Adulto , Idoso , Epitopos/sangue , Epitopos/genética , Feminino , Expressão Gênica , Humanos , Oxirredutases Intramoleculares/sangue , Oxirredutases Intramoleculares/genética , Masculino , Glicoproteínas de Membrana/sangue , Glicoproteínas de Membrana/genética , Pessoa de Meia-Idade , Proteínas de Neoplasias/sangue , Proteínas de Neoplasias/genética , Sensibilidade e Especificidade , Antígeno gp100 de MelanomaRESUMO
BACKGROUND: Hepatitis C virus (HCV) infection is a dynamic process during which viral genetic variants continuously develop as a result of the virus adaptation to the host's immune system. The level of viremia and the complexity of the hypervariable region 1 (HVR 1) quasispecies of hepatitis C virus during antiviral therapy reflect the dynamic balance between the viral and host components in response to therapy. OBJECTIVE: The aim of the study was to evaluate the dynamics of HCV viremia and the complexity of the HVR 1 quasispecies during the induction phase of a triple combination therapy regimen in nonresponders to earlier anti-HCV treatment. STUDY DESIGN: Ten patients with chronic hepatitis C undergoing antiviral combination therapy with interferon-alpha, ribavirin, and amantadine were studied. The serum HCV RNA level was monitored by a quantitative RT-PCR assay up to 3 months after start of treatment. The HVR 1 quasispecies complexity was analysed by an "in house" nested RT-PCR mediated single-strand conformation polymorphism (SSCP) assay. RESULTS: Baseline serum HCV RNA levels ranged from 1.94x10(6) to 5.53x10(6) copies/ml. In all patients, HCV subtype 1b was found. At the start of therapy, the SSCP assay revealed a high complexity pattern (at least six SSCP bands) in all patients. None of the patients responded within 4 weeks of treatment, however, the serum HCV RNA level decreased by one to two logs in eight patients. At week 4 after start of treatment, there was a decrease of SSCP bands in five patients. In four patients, SSCP bands remained unchanged and in one patient SSCP bands increased. At month 3 after start of treatment, serum HCV RNA was not detectable in one patient. CONCLUSION: Because of the low number of patients involved in this study, prediction of therapeutical success based on the quasispecies complexity was not possible. Larger studies are urgently needed.
Assuntos
Antivirais/uso terapêutico , DNA Viral/sangue , Hepacivirus/genética , Hepatite C Crônica/virologia , Carga Viral , Adulto , Amantadina/farmacologia , Amantadina/uso terapêutico , Antivirais/farmacologia , Quimioterapia Combinada , Feminino , Hepacivirus/classificação , Hepacivirus/efeitos dos fármacos , Hepatite C Crônica/tratamento farmacológico , Humanos , Interferon-alfa/farmacologia , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Filogenia , Polimorfismo Conformacional de Fita Simples , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ribavirina/farmacologia , Ribavirina/uso terapêuticoRESUMO
The relationship between the complexity of the hypervariable region 1 (HVR1) quasispecies of hepatitis C virus (HCV) and responsiveness to interferon-alpha (IFN) therapy was studied in patients with chronic hepatitis C. Twelve HCV-RNA-positive patients were treated daily with high dose IFN and ribavirin for 4 weeks, and then with IFN 3 MIU (Million International Units) TIW (three times per week) and ribavirin for 6 months. The HVR1 quasispecies complexity was analyzed by nested polymerase chain reaction-mediated single-strand conformation polymorphism (SSCP). The baseline HCV-RNA levels in the study group ranged from 10(6) to 10(7) copies/ml. All patients exhibited HCV genotype 1 b. Initial SSCP analysis revealed four (33.3%) patients with a low complexity pattern (SSCP bands < or =4) and eight (66.6%) patients with high complexity pattern (SSCP bands >4). After 4 weeks of IFN therapy, one patient became HCV negative, and among those remaining positive, the HCV-RNA levels decreased by 2 to 3 logs and the number of SSCP decreased by 2 to 3 bands per sample. After 6 months of IFN therapy, five (41.7%) patients became HCV-RNA-negative. Seven (58.3%) patients did not respond to IFN therapy with sustained viral load from 10(3) to 10(5) copies/ml, and high complexity SSCP patterns. Our data support the HVR quasispecies complexity to be an independent predictive factor for IFN responsiveness in patients infected with HCV.
Assuntos
Antivirais/uso terapêutico , Variação Genética , Hepacivirus/genética , Hepatite C/tratamento farmacológico , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Quimioterapia Combinada , Feminino , Genoma Viral , Hepacivirus/classificação , Hepacivirus/isolamento & purificação , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Polimorfismo Conformacional de Fita Simples , RNA Viral/sangue , RNA Viral/genética , Proteínas Recombinantes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Carga ViralRESUMO
AIM: To isolate and genotype Borrelia burgdorferi genospecies in serum samples of Croatian patients with erythema migrans. METHODS: DNA isolates from sera of patients with erythema migrans were analyzed by nested polymerase chain reaction (PCR), amplifying a segment of flagellin gene with primers encompassing the conserved region of the gene. To screen PCR products for heterogeneity, we performed single-stranded conformation polymorphism (SSCP) analysis. The samples showing differences in SSCP patterns were sequenced, and the sequence compared in the GeneBank for sequence homology with known Borrelia burgdorferi genospecies. We also constructed phylogenetic tree of all known borrelial sequences. RESULTS: The nested PCR method using specially designed flagellin gene primers, achieved the sensitivity of 10 genome copies (0.01 pg of purified Borrelia burgdorferi DNA from culture) by dilution analysis. The assay specificity was confirmed by amplification of a part of the flagellin gene from different bacterial species. The primer pairs successfully amplified only Borrelia burgdorferi flagellin gene. The genome of Borrelia burgdorferi sensu lato was detected in the sera of all 10 tested patients with erythema migrans. Sequence data and phylogenetic analysis confirmed that all amplified samples belonged to Borrelia afzelii genospecies. CONCLUSION: Phylogenetic tree analysis placed the borrelial isolates together with Borrelia afzelii sequences into a single group. This finding was additionally supported by sequence homology analysis, which produced a homology score of 99%. In patients with erythema migrans who come from the northwest Croatia, an endemic area for Lyme borreliosis, Borrelia afzelii was the cause of skin manifestations of Lyme borreliosis.
Assuntos
Grupo Borrelia Burgdorferi/genética , Grupo Borrelia Burgdorferi/isolamento & purificação , Reação em Cadeia da Polimerase , Croácia/epidemiologia , DNA Bacteriano/análise , Eritema Migrans Crônico/epidemiologia , Eritema Migrans Crônico/microbiologia , Genótipo , Humanos , Filogenia , Polimorfismo Conformacional de Fita Simples , Sensibilidade e Especificidade , Homologia de Sequência do Ácido NucleicoRESUMO
The populations that colonized Siberia diverged from one another in the Paleolithic and evolved in isolation until today. These populations are therefore a rich source of information about the conditions under which the initial divergence of modern humans occurred. In the present study we used the HLA system, first, to investigate the evolution of the human major histocompatibility complex (MHC) itself, and second, to reveal the relationships among Siberian populations. We determined allelic frequencies at five HLA class II loci (DRB1, DQA1, DQB1, DPA1, and DPB1) in seven Siberian populations (Ket, Evenk, Koryak, Chukchi, Nivkh, Udege, and Siberian Eskimo) by the combination of single-stranded conformational polymorphism and DNA sequencing analysis. We then used the gene frequency data to deduce the HLA class II haplotypes and their frequencies. Despite high polymorphism at four of the five loci, no new alleles could be detected. This finding is consistent with a conserved evolution of human class II MHC genes. We found a high number of HLA class II haplotypes in Siberian populations. More haplotypes have been found in Siberia than in any other population. Some of the haplotypes are shared with non-Siberian populations, but most of them are new, and some represent "forbidden" combinations of DQA1 and DQB1 alleles. We suggest that a set of "public" haplotypes was brought to Siberia with the colonizers but that most of the new haplotypes were generated in Siberia by recombination and are part of a haplotype pool that is turning over rapidly. The allelic frequencies at the DRB1 locus divide the Siberian populations into eastern and central Siberian branches; only the former shows a clear genealogical relationship to Amerinds.
Assuntos
Genes MHC da Classe II , Polimorfismo Genético/genética , Alelos , Feminino , Frequência do Gene , Antígenos HLA-D/genética , Homozigoto , Humanos , Masculino , Filogenia , Análise de Sequência de DNA , Sibéria/etnologiaRESUMO
Between 2 May 1991 and 2 November 1992, 4425 wounded people were treated at the Clinical Hospital of Osijek, Croatia. A hundred and fifteen (2.6 per cent) had a urogenital injury, 64 (56 per cent) of whom had penetrating kidney injuries. Sixteen (25 per cent) of this 64 were caused by gunshot wounds and 48 (75 per cent) by fragments of mines, mortars or grenades. The majority of the 64 kidney injuries had also associated injuries of some other major organ system, particularly in the abdomen, with only three cases of isolated kidney injury. In 53 patients (82.8 per cent) surgical access was by transabdominal incision, in nine (14 per cent) by extraperitoneal flank incision and in two cases thoracophrenolaparotomy was also performed. Nephrectomy was performed in 16 patients (25 per cent). In 46 (75 per cent) an organ-sparing procedure was done: kidney sutures in 28 (43.8 per cent), kidney resection in five (7.8 per cent) and exploration only in 15 (23.4 per cent). Intrahospital deaths occurred in 11 (18 per cent), seven in the operating theatre. An evaluation of the 6-month follow up for 90 per cent of the surviving patients is presented. It seems that the frequency of renal war injuries was lower than usually reported. Associated abdominal injuries justified surgical access by transabdominal incision. The high mortality rate is explained by a large number of associated injuries and by the proximity of the battlefield with resulting rapid transport of patients (average 52 min), which excluded the possibility of separating out the moribund patients. Long-term follow up confirmed the benefits of the conserving surgical approach.
Assuntos
Traumatismos por Explosões/cirurgia , Rim/lesões , Guerra , Ferimentos por Arma de Fogo/cirurgia , Adolescente , Adulto , Idoso , Traumatismos por Explosões/mortalidade , Criança , Croácia , Humanos , Rim/cirurgia , Pessoa de Meia-Idade , Nefrectomia , Resultado do Tratamento , Ferimentos por Arma de Fogo/mortalidadeRESUMO
Five acute promyelocytic leukemia (APL) patients who achieved a complete remission (CR) with all-trans retinoic acid (ATRA) underwent residual disease monitoring through reverse transcription polymerase chain reaction (PCR) for PML/retinoic acid receptor-alpha (PML/RAR alpha) fusion transcript. All received consolidation chemotherapy in CR, one in the form of autologous bone marrow transplantation (ABMT). In four of the patients PCR was positive for the PML/RAR alpha transcript immediately after ATRA treatment and/or after the first consolidation chemotherapy course. In the patient treated with ABMT, positivity was still detected six months after ABMT. One patient given five repeated courses of chemotherapy was PCR negative for PML/RAR alpha after 14 months in CR. Our pilot study confirmed that ATRA is a highly efficient induction therapy for APL in various stages of the disease, but ATRA alone cannot cure the disease. PCR should be considered a fundamental assay for assessing minimal residual disease in CR that will influence further treatment strategies and permit evaluation of treatment results.
Assuntos
Leucemia Promielocítica Aguda/tratamento farmacológico , Receptores do Ácido Retinoico/genética , Transcrição Gênica , Tretinoína/uso terapêutico , Leucemia Promielocítica Aguda/genética , Monitorização Fisiológica , Neoplasia Residual , Reação em Cadeia da Polimerase , Receptor alfa de Ácido Retinoico , EstereoisomerismoRESUMO
The consensus motifs of HLA-Cw3, -Cw4, -Cw6, and -Cw7 ligands were determined by pool sequencing. Together with information obtained by sequencing of some prominent individual peptides, the results indicate the following: (i) all four HLA-C molecules are associated with peptides. (ii) These peptides adhere to allele-specific motifs that are similar to those of to HLA-A or -B molecules; they have a preferred length of nine amino acids and an anchor residue at the C terminus. (iii) All four HLA-C molecules analyzed exhibit related peptide motifs, although each allelic product shows individual characteristics in fine specificity. (iv) Processing and origin of peptides appear not to be different from that of other class I molecules. (v) No obvious difference at C-terminal position 9 was present in the peptides isolated from the two dimorphic variants of HLA-C that determine dominant resistance to natural killer NK1-specific cells (HLA-Cw4, -Cw6) or to NK2-specific cells (HLA-Cw3, -Cw7) and that differ in two residues in or near the pocket at position 9.
Assuntos
Antígenos HLA-C/metabolismo , Peptídeos/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Linhagem Celular , Sequência Consenso , Antígenos HLA-A/química , Antígenos HLA-A/metabolismo , Antígenos HLA-B/química , Antígenos HLA-B/metabolismo , Antígenos HLA-C/biossíntese , Antígenos HLA-C/química , Humanos , Ligantes , Camundongos , Dados de Sequência Molecular , Peptídeos/química , Homologia de Sequência de Aminoácidos , TransfecçãoRESUMO
To determine the organization of the DP region in the Mbc of anthropoid primates, we constructed contig maps from cosmid clones of the chimpanzee and orangutan, representatives of the infraorder Catarrhini, as well as of the cotton-top tamarin, a representative of the infraorder Platyrrhini. We found the maps to be remarkably similar to each other and to the previously published map of the human DP region. In each of the four species, the DP region consists of four loci arranged in the same order (DPB2 . . . DPA2 . . . DPB1 . . . DPA1) and in the same transcriptional orientation (tail-to-tail). The regions in the four species are of approximately the same length and many of the restriction sites are shared between species. The inserts of most Alu elements, of a ribosomal protein pseudogene, and of an IgC epsilon-like pseudogene are found in corresponding positions in all four species. The data indicate that the human-type organization of the DP region was established before the divergence of the Catarrhini and Platyrrhini lines more than 37 million years ago and that it has remained principally intact since that time. This conservation of the DP region is in striking contrast to the evolutionary instability of certain other Mbc regions, in particular those occupied by the DRB or C4 and CYP21 loci. We interpret the stability of the DP region as an indication that the region is being phased out functionally.
Assuntos
Genes MHC da Classe II , Primatas/genética , Animais , Sequência de Bases , Evolução Biológica , Southern Blotting , Feminino , Biblioteca Genômica , Antígenos HLA-DP/genética , Dados de Sequência Molecular , Pan troglodytes/genética , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Pongo pygmaeus/genética , Saguinus , Homologia de Sequência do Ácido NucleicoRESUMO
Class I molecules of the major histocompatibility complex (MHC) transport peptides to the cell surface for surveillance by T cells. Ligand specificity is stringent and differs from allele to allele. Here we report analysis of natural ligands of 'unconventional' glycophosphatidyl-anchored mouse class I molecules, Qa-2. The function of these molecules is unclear; they can serve as recognition structures for 'unrestricted' cytotoxic T cells but have not been found to present peptides to T cells, although the DNA sequence suggests a similar peptide binding groove to that of 'conventional' class I molecules, and other unconventional class I molecules can present antigens in a few cases. Pool sequencing of natural Qa-2 ligands shows that Qa-2 molecules are indeed peptide receptors, having ligand specificity similar to that of conventional class I molecules, that is, a predominant length of nine amino acids, anchor positions, and hydrophobic termination of peptides. But ligand specificity is much more stringent than with other class I molecules: of the nine positions, two are anchors and four have rather limited occupancy.
Assuntos
Antígenos de Histocompatibilidade Classe I/metabolismo , Sequência de Aminoácidos , Animais , Sítios de Ligação , Camundongos , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , Peptídeos/química , Peptídeos/metabolismoRESUMO
We investigated values of uric acid and lipids in serum of 168 men, workers at a printing-house. The average uricemia found is significant higher in testees who have values of triglycerides more than 2.00 mmol/l, than in those ones who had lower values of triglycerides, P < 0.05. We could not find a notable difference of uricemia in testees who had higher values of cholesterol, but normal values of triglycerides related to those testees who had normal values of cholesterol in serum, P > 0.05.
Assuntos
Hiperlipidemias/sangue , Ácido Úrico/sangue , Adulto , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
The two infraorders of anthropoid primates, Platyrrhini (New World monkeys) and Catarrhini (Old World monkeys and the hominoids) are estimated to have diverged from a common ancestor 37 million years ago. The major histocompatibility complex class II DRB gene and haplotype polymorphism of the Catarrhini has been characterized in several recent studies. The present study was undertaken to obtain information on the DRB polymorphism of the Platyrrhini. Fifty-five complete exon 2 DRB sequences were obtained from six species of Platyrrhini representing both the Callitrichidae and the Cebidae families. Combined with the results of a parallel contig mapping study, our data indicate that at least three loci (DRB1*03, DRB3, and DRB5) are shared by the Catarrhini and the Platyrrhini. However, the three loci are occupied by functional genes in the former infraorder and mostly by pseudogenes in the latter. Instead of the pseudogenes, the Platyrrhini have evolved a new set of apparently functional genes-DRB11 and DRB*W12 through DRB*W19, which have thus far not been found in the Catarrhini. The DRB*W13, *W14, *W15, *W17, *W18, and *W19 genes seem to be restricted to the Cebidae family, whereas the DRB*W16 locus has so far been documented in the Callitrichidae family only. The DRB alleles of the cotton-top tamarin, and perhaps also those of the common marmoset (both members of the family Callitrichidae), are characterized by low nucleotide diversity, possibly indicating that they diverged from a common ancestral gene relatively recently.
Assuntos
Cebidae/genética , Complexo Principal de Histocompatibilidade/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Códon , DNA , Dados de Sequência Molecular , Polimorfismo Genético , Alinhamento de SequênciaRESUMO
The DRB region of the human and great-ape major histocompatibility complex displays not only gene but also haplotype polymorphism. The number of genes in the human DRB region can vary from one to four, and even greater variability exists among the DRB haplotypes of chimpanzees, gorillas, and orangutans. Accumulating evidence indicates that, like gene polymorphism, part of the haplotype polymorphism predates speciation. In an effort to determine when the gene haplotype polymorphisms emerged in the primate lineage, we sequenced three cDNA clones of the New-World monkey, the cottontop tamarin (Saguinus oedipus). We could identify two DRB loci in this species, one (Saoe-DRB1) occupied by apparently functional alleles (*0101 and *0102) which differ by only two nucleotide substitutions and the other (Saoe-DRB2) occupied by an apparent pseudogene. The Saoe-DRB2 gene contains an extra sequence derived from the 3' portion of exon 2 and placed 5' to this exon. This sequence contains a stop codon which makes the translation of the bulk of the Saoe-DRB2 gene unlikely. Preliminary Southern blot hybridization analysis with probes derived from these two genes suggests that both the DRB gene polymorphism and the haplotype polymorphism in the cottontop tamarin may be low. In most individuals the DRB region of this species probably consists of three genes. Comparisons of the Saoe-DRB sequences with those of other primates suggest that probably all of the DRB genes found until now in the Catarrhini were derived from a common ancestor after the separation of the Catarrhini and Platyrrhini lineages. The extant DRB gene and haplotype polymorphism may therefore have been founded in the mid-Oligocene some 33 Mya.