RESUMO
PURPOSE: The aim of the present study is to propose a new contrast agent that can be easily applied both to CT and dissection studies to replace lead oxide based formulas for comparative anatomical analyses of the vascularisation of cadaveric specimens. METHODS: The infusion material was an epoxy resin, especially modified by the addition of barium sulphate to enhance its radiopacity. The final copolymer was toxicologically safe. To test the properties of the new material, several cadaveric limb injections were performed. The injected specimens were both CT scanned to perform 3D vascular reconstructions and dissected by anatomical planes. RESULTS: There was a perfect correspondence between the image studies and the dissections: even the smallest arteries on CT scan can be identified on the specimen and vice versa. The properties of the epoxy allowed an easy dissection of the vessels. CONCLUSIONS: The new imaging techniques available today, such as CT scan, can evaluate the vascular anatomy in high detail and 3D. This new contrast agent may help realising detailed vascular studies comparing CT scan results with anatomical dissections. Moreover, it may be useful for teaching surgical skills in the field of plastic surgery.
Assuntos
Anatomia Comparada/métodos , Meios de Contraste , Resinas Epóxi , Dissecação , Pé/irrigação sanguínea , Humanos , Tomografia Computadorizada por Raios XRESUMO
We performed a genome-wide association study comparing a cohort of 144 human immunodeficiency virus (HIV type 1-infected, untreated white long-term nonprogressors (LTNPs) with a cohort of 605 HIV-1-infected white seroconverters. Forty-seven single-nucleotide polymorphisms (SNPs), located from class I to class III major histocompatibility complex (MHC) subregions, show statistical association (false discovery rate, <0.05) with the LTNP condition, among which 5 reached genome-wide significance after Bonferonni correction. The MHC LTNP-associated SNPs are ordered in ≥4 linkage disequilibrium blocks; interestingly, an MHC class III linkage disequilibrium block (defined by the rs9368699 SNP) seems specific to the LTNP phenotype.
Assuntos
Progressão da Doença , Genes MHC Classe I/genética , Infecções por HIV/genética , HIV-1 , Polimorfismo de Nucleotídeo Único , Proteínas de Ligação a DNA/genética , Frequência do Gene , Estudo de Associação Genômica Ampla , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Complexo Principal de Histocompatibilidade/genética , RNA Longo não Codificante , RNA não Traduzido , Fatores de Tempo , Fatores de Transcrição/genéticaRESUMO
The different phases of production of farmed and hunted wild game fresh meat are described. The importance of reducing the stress resulting from handling procedures (capture, restraint, transport) before the slaughtering of animals is highlighted, due to its adverse effects on meat quality. The hygienic and animal welfare criteria to be adopted in the slaughtering of wild game are described. The importance of carcass inspection immediately after slaughtering is stated, so that meat can be destined for human consumption. Possible alterations occurring in fresh and refrigerated meat, that are capable of compromising its consumability, are presented.
Assuntos
Cervos/crescimento & desenvolvimento , Manipulação de Alimentos/métodos , Carne/normas , Animais , Inspeção de Alimentos/métodos , HumanosRESUMO
The levels of adenosine deaminase (ADA) were determined in the erythrocytes of 10 patients with sexually transmitted HIV-1 infection [five cases with AIDS-related complex (ARC) and five with AIDS] before and after therapy with zidovudine (azidothymidine; AZT). A linear increase in ADA activity was observed during the second and third months of zidovudine treatment, with a final increase of about threefold after 3 months of drug administration. The concentration of adenosine triphosphate (ATP) was significantly lower in the erythrocytes of the same group of patients with respect to healthy controls, and a further decrease was noted after 3 months of zidovudine treatment. The results obtained indicate that treatment of ARC/AIDS subjects with zidovudine induces metabolic changes which could be responsible for the development of anaemia, an adverse effect frequently associated with zidovudine therapy.
Assuntos
Complexo Relacionado com a AIDS/tratamento farmacológico , Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , Adenosina Desaminase/sangue , Eritrócitos/enzimologia , HIV-1/efeitos dos fármacos , Zidovudina/uso terapêutico , Complexo Relacionado com a AIDS/enzimologia , Síndrome da Imunodeficiência Adquirida/enzimologia , Adulto , Anemia/induzido quimicamente , Eritrócitos/efeitos dos fármacos , Humanos , Zidovudina/efeitos adversosRESUMO
In this review, the origin and evolution of the human T-cell lymphotropic virus type II (HTLV-II) are discussed, with particular emphasis on its high genomic stability. In particular, it appears that the virus originated in the African continent and has been infecting human populations for several thousands of years. The very low divergence accumulated on average between different viral strains during such a long period could be explained by considering that in infected individuals the viral amplification could be due mainly to the clonal expansion of the infected cells, via cellular mitosis, rather than to reverse transcription. HTLV-II was introduced into the American continent during one or more migrations of HTLV-II-infected Asian populations over the Bering land bridge, some 15,000-35,000 years ago. Finally, during the last few decades, HTLV-II has been transmitted from native Amerindians to injecting drug users (IDUs). It might be speculated that at least two separate introductions of HTLV-II in European IDUs from US IDUs have occurred, due to the practice of needle-sharing among IDUs.
Assuntos
Evolução Biológica , Vírus Linfotrópico T Tipo 2 Humano/genética , Replicação Viral/genética , Variação Genética , Genoma Viral , Infecções por HTLV-II/complicações , Infecções por HTLV-II/epidemiologia , Infecções por HTLV-II/transmissão , Vírus Linfotrópico T Tipo 2 Humano/fisiologia , Humanos , Abuso de Substâncias por Via Intravenosa/complicaçõesRESUMO
The reverse transcriptase of HIV-1 (AIDS virus) is characterized by the presence of two highly immunogenic proteins of 66 and 51 kD known to be enzymatically active as a complex p66/51. Using an activity gel procedure that allows identification of catalytic polypeptides in situ after PAGE in denaturing conditions, we visualized two major active bands of 66 and 51 kD of reverse transcriptase from highly purified preparations of HIV-1. We show that both p66 and p51 are enzymatically active. An additional active band was also associated with a 165 kD polypeptide, representing about 2-4% of total activity and possibly corresponding to the putative gag-pol precursor. In H9-infected cells the 66 kD active band became visible 70 hours after infection. These studies show that the two major forms of reverse transcriptase (66 and 51 kD) of HIV-1 are independently active and that a higher Mr form of 165 kD is also enzymatically active.
Assuntos
HIV-1/enzimologia , DNA Polimerase Dirigida por RNA/metabolismo , Linhagem Celular , Eletroforese em Gel de Poliacrilamida , Peso Molecular , Poli A , Poli T , Polinucleotídeos , DNA Polimerase Dirigida por RNA/isolamento & purificação , Especificidade por SubstratoRESUMO
We report the cellular and molecular characterization of two cases of Castleman's disease, plasma cell variant, that differed in their clinical presentation and course. Patient 1 had Castleman's disease in association with Kaposis's sarcoma unrelated to human immunodeficiency virus (HIV) infection and died while he was receiving an aggressive chemotherapeutic regimen for Kaposi's sarcoma. Patient 2 had an isolated retroperitoneal lymphoid mass with an adjacent enlarged limph nodes and his symptoms disappeared completely following the surgical removal of both. Pathologic and immunohistochemical analyses in both cases, revealed that there was a massive infiltration of polyclonal plasma cells in the interfollicular areas of the lymph nodes. Immunoglobulin gene rearrangement studies confirmed the polyclonal nature of B-lineage cells in the involved lymph nodes. Southern blot experiments failed to demonstrate the presence of EBV genome copies in the same lymph nodes. These paradigmatic cases lend further support to the notion that Castleman's disease is an extremely heterogeneous entity.
RESUMO
The authors have investigated terminal deoxynucleotidil transferase (TdT) activity in the spleen, liver and thymus of a human foetus of 23 weeks. TdT significant levels have been found and two different molecular forms were defined in each tissue.
Assuntos
DNA Nucleotidilexotransferase/metabolismo , DNA Nucleotidiltransferases/metabolismo , Feto/enzimologia , DNA Nucleotidilexotransferase/isolamento & purificação , Feminino , Humanos , Fígado/enzimologia , Gravidez , Baço/enzimologia , Timo/enzimologiaRESUMO
To establish the in vivo cellular tropism of human T-cell leukemia virus type II (HTLV-II) in peripheral blood, subpopulations of mononuclear cells isolated from patients with a history of drug abuse and with high proviral load were analyzed by polymerase chain reaction for the presence of the proviral sequences. After purification of cellular subsets by immunomagnetic fractionation of blood cells of an infected patient, HTLV-II DNA was detected in CD4+ and CD8+ T-cells as well as in CD19+ B-cells. A positive PCR signal was obtained for purified B-cells also at limiting dilutions. This observation was confirmed by purifying the B-cell fraction by a two-step immunomagnetic procedure from the peripheral blood of another patient with very high HTLV-II copy number and quantifying the B-cell proviral load by means of competitive PCR. A proviral copy number of 90/100 B-cells was found, demonstrating that the great majority of these cells were infected by HTLV-II in this subject. The results indicate that HTLV-II has a broad host range in some infected individuals, showing an enlargement of cellular tropism to B lymphocytes and suggesting that this expression is associated with an increase in proviral load.
Assuntos
Linfócitos B/virologia , Infecções por HTLV-II/virologia , Vírus Linfotrópico T Tipo 2 Humano/fisiologia , Anticorpos Monoclonais , Antígenos CD/análise , Antígenos CD19 , Antígenos de Diferenciação de Linfócitos B/análise , Relação CD4-CD8 , Infecções por HTLV-II/imunologia , Vírus Linfotrópico T Tipo 2 Humano/isolamento & purificação , Humanos , Reação em Cadeia da PolimeraseRESUMO
The molecular characterization of two human T-cell lymphotropic virus type II (HTLV-II) isolates, Gu and Va, obtained from Italian injecting drug users (IDUs) has indicated that these isolates belong to the HTLV-IIb subtype. To establish whether Italian IDUs are also infected by the HTLV-IIa variant, sequencing of the gp21 env gene of proviral DNA from further patients was carried out. Two new isolates, Bo and Md, were found, which presented a divergence of 0.4-0.7% from the IIa prototype HTLV-II-Mo, thus indicating that they belong to the HTLV-IIa subtype. The results strongly support the existence of two distinct molecular subtypes of HTLV-II infecting Italian IDUs and demonstrate that, although the IIb subtype appears to be prevalent, there is the same variability for this virus in Europe as found in the United States. The Italian IIb isolates were also seen to encode an additional 25 amino acids at the C-terminal end of tax protein, as already shown for other IIb isolates. The identification of two HTLV-II molecular subtypes among Italian drug addicts will be useful in tracing the worldwide distribution of this virus and in further understanding its molecular structure and biology.
Assuntos
Infecções por HTLV-II/microbiologia , Vírus Linfotrópico T Tipo 2 Humano/genética , Abuso de Substâncias por Via Intravenosa/microbiologia , Sequência de Aminoácidos , Sequência de Bases , Produtos do Gene env/química , Produtos do Gene env/genética , Genes env , Infecções por HTLV-II/etiologia , Vírus Linfotrópico T Tipo 2 Humano/classificação , Humanos , Itália , Dados de Sequência Molecular , Proteínas Oncogênicas de Retroviridae/química , Proteínas Oncogênicas de Retroviridae/genética , Abuso de Substâncias por Via Intravenosa/complicações , Produtos do Gene env do Vírus da Imunodeficiência HumanaRESUMO
The liver, bone marrow and cord blood of 30 human foetuses between the 15th and 21st weeks of gestational age were examined. Liver suspensions were investigated both by immunofluorescent and biochemical assay; cord blood suspensions and bone marrow touches with immunofluorescent assay. The results indicate the existence of a few TdT+ cells in the liver, cord blood and bone marrow of human foetuses in the ages studied. The peaks for each organ were: 15 +/- 1.60 (mean +/- SD) TdT+ cells in the liver, 12 +/- 2 in the bone marrow and 18 +/- 2.83 in the cord blood. In all the organs TdT+ cells decrease in the later weeks. In the liver, the results of the immunofluorescent assay were confirmed by the biochemical activity.
Assuntos
Medula Óssea/enzimologia , DNA Nucleotidilexotransferase/sangue , DNA Nucleotidiltransferases/sangue , Sangue Fetal/enzimologia , Fígado/enzimologia , Feto , Imunofluorescência , HumanosRESUMO
The authors have determined TdT levels in a case of Ph1-positive AML. Peripheral blood cells and bone marrow cells taken during the various phases of the disease were examined. Liquor cells were analyzed when symptomatic central nervous system involvement occurred. High TdT levels were found in all of the phases of the disease including the liquor. TdT eluted at various isoelectric points indicating a shifting of the activity to greater molarity during progress of the disease. Two different forms of TdT were present in the liquor. The authors speculate about the existence of a relation between TdT levels and Ph1-positive leukemia. They point out the importance of TdT levels as functional criterion of remission in acute leukemia. Finally, the existence of different forms of TdT could be the expression of a clonal selection caused by therapy or of a spontaneous clonal competition.
Assuntos
Cromossomos Humanos 21-22 e Y , DNA Nucleotidilexotransferase/metabolismo , DNA Nucleotidiltransferases/metabolismo , Leucemia Mieloide Aguda/enzimologia , Adolescente , Antineoplásicos/uso terapêutico , Medula Óssea/enzimologia , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Pré-Leucemia/enzimologiaRESUMO
The inotropic effect of endothelin-2 was investigated on isolated preparations of human atrium taken from patients undergoing cardiac surgery. Pectinate muscle fragments were set up in isolated organ chambers under isometric conditions and electrically stimulated through two ring platinum electrodes. Endothelin-2 (10(-11)-10(-8) M) increased both the force and velocity of contraction in a concentration-dependent manner, giving a maximum response of about 70% of that attainable with histamine or epinephrine. The putative endothelin B receptor agonist, the C-terminal hexapeptide endothelin-(16-21), did not affect inotropic activity. The action of endothelin-2 was not modified by indomethacin and propranolol, thus excluding an involvement of endogenous prostaglandins or catecholamines. The adenylate-cyclase activator, forskolin, and the calcium agonist, Bay K 8644, at concentrations able to enhance the inotropic effect induced by histamine and epinephrine, did not modify the action of endothelin-2. The data show that endothelin-2 has a strong positive inotropic effect on the isolated human myocardium. The effect seems to be independent of the sympathetic system and is unlikely to involve slow channel conductance or cyclic AMP. The lack of activity of endothelin fragment suggests that an endothelin receptor subtype, similar to that found in rat aorta, is present on human atrium.
Assuntos
Endotelinas/farmacologia , Átrios do Coração/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Átrios do Coração/química , Humanos , Técnicas In Vitro , Masculino , Receptores de Superfície Celular/efeitos dos fármacos , Receptores de Endotelina , Estimulação QuímicaRESUMO
The contractile effect of endothelin-2 was investigated in isolated human saphenous vein preparations. Spare segments taken from revascularized patients were set up in isolated organ chambers and mechanical activity was recorded under isometric conditions. Endothelin-2 (10(-11)-10(-7) M) evoked a dose-dependent contractile response, having the same efficacy as noradrenaline and 100 times its potency. Conversely, the "selective" ETB agonist, C-terminal hexapeptide endothelin (16-21), was completely ineffective. The activity of endothelin-2 was not modified by phentolamine, saralasin and indomethacin, thus excluding a direct or indirect activation of alpha-adrenoceptors and angiotensin receptors as well as the synthesis of cyclooxygenase products. Calcium removal from nutrient fluid depressed, but not fully abolished, the contractile effect of endothelin-2; furthermore, calcium channel blockers, verapamil and nifedipine, produced only a partial inhibition of the endothelin-2-induced contractions. These observations suggest that endothelin-2 induces a direct activation of specific receptors in the saphenous vein muscle and that both intracellular and extracellular calcium pools may be involved in the contractile effect of the peptide.
Assuntos
Endotelinas/farmacologia , Vasoconstrição/efeitos dos fármacos , Cálcio/fisiologia , Bloqueadores dos Canais de Cálcio/farmacologia , Humanos , Técnicas In Vitro , Indometacina/farmacologia , Masculino , Fentolamina/farmacologia , Veia Safena/efeitos dos fármacos , Saralasina/farmacologiaRESUMO
An activity gel method was used to analyze the catalytic polypeptides of polymerases alpha and beta in human acute myeloblastic and lymphoblastic leukemia. A 175 kDa alpha-polymerase was found in 85% of bone marrow and in 57% of peripheral blood samples. At variance, a 40 kDa beta-polymerase was found in 94% of peripheral blood and only in 12% of bone marrow samples. No difference in the pattern of polymerase expression was found according to the type of leukemia and the disease status. The role of these enzymes in leukemia and their implications in drug sensitivity are discussed.