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1.
Br J Surg ; 105(6): 736-742, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29532908

RESUMO

BACKGROUND: Liver transplantation is considered the standard of care for patients with hepatocellular carcinoma (HCC) within the Milan criteria. Liver transplantation in patients with unresectable colorectal cancer with liver-only disease has been shown to be associated with a 5-year overall survival rate of 56 per cent, compared with 9 per cent in patients receiving standard palliative chemotherapy. The aim of the present study was to compare disease-free (DFS) and overall (OS) survival after liver transplantation in patients with HCC and those with colorectal metastases. METHODS: Data were collected from the SEcondary CAncer (SECA) study database and an institutional (national) database of patients undergoing liver transplantation for HCC; all liver-transplanted patients were included. Patients with colorectal metastases treated by liver transplantation were divided into high- and low-risk groups for mortality based on carcinoembryonic antigen levels, response to chemotherapy, largest lesion at time of transplantation and time from primary surgery to transplantation. RESULTS: Patients with colorectal metastases had a median of 8 lesions, compared with 1 in patients with HCC within the Milan criteria. DFS was shorter in both the high-risk and the low-risk colorectal cancer groups compared with that in patients with HCC. The 5-year OS rate in the low-risk colorectal cancer group was 75 per cent, compared with 76 per cent in patients with HCC within the Milan criteria. The 5-year OS rate in patients with HCC beyond the Milan criteria was 56 per cent. CONCLUSION: The low-risk group of patients with colorectal cancer and unresectable liver-only disease had a 5-year OS rate following liver transplantation similar to that of patients with HCC with lesions within the Milan criteria.


Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/cirurgia , Transplante de Fígado/mortalidade , Adolescente , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Criança , Neoplasias Colorretais/mortalidade , Neoplasias Colorretais/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/secundário , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Análise de Sobrevida , Adulto Jovem
2.
Osteoarthr Cartil Open ; 6(2): 100466, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38623306

RESUMO

Objective: A prototype infrared attenuated total reflection (IR-ATR) laser spectroscopic system designed for in vivo classification of human cartilage tissue according to its histological health status during arthroscopic surgery is presented. Prior to real-world in vivo applications, this so-called osteoarthritis (OA) scanner has been tested at in vitro conditions revealing the challenges associated with complex sample matrices and the accordingly obtained sparse spectral datasets. Methods: In vitro studies on human knee cartilage samples at different contact pressures (i.e., 0.2-0.5 â€‹MPa) allowed recording cartilage degeneration characteristic IR signatures comparable to in vivo conditions with high temporal resolution. Afterwards, the cartilage samples were assessed based on the clinically acknowledged osteoarthritis cartilage histopathology assessment (OARSI) system and correlated with the obtained sparse IR data. Results: Amide and carbohydrate signal behavior was observed to be almost identical between the obtained sparse IR data and previously measured FTIR data used for sparse partial least squares discriminant analysis (SPLSDA) to identify the spectral regions relevant to cartilage condition. Contact pressures between 0.3 and 0.4 â€‹MPa seem to provide the best sparse IR spectra for cylindrical (d â€‹= â€‹3 â€‹mm) probe tips. Conclusion: Laser-irradiating IR-ATR spectroscopy is a promising analytical technique for future arthroscopic applications to differentiate healthy and osteoarthritic cartilage tissue. However, this study also revealed that the flexible connection between the laser-based analyzer and the arthroscopic ATR-probe via IR-transparent fiberoptic cables may affect the robustness of the obtained IR data and requires further improvements.

3.
Nature ; 449(7159): 189-91, 2007 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-17851517

RESUMO

After the initial discoveries fifteen years ago, over 200 extrasolar planets have now been detected. Most of them orbit main-sequence stars similar to our Sun, although a few planets orbiting red giant stars have been recently found. When the hydrogen in their cores runs out, main-sequence stars undergo an expansion into red-giant stars. This expansion can modify the orbits of planets and can easily reach and engulf the inner planets. The same will happen to the planets of our Solar System in about five billion years and the fate of the Earth is matter of debate. Here we report the discovery of a planetary-mass body (Msini = 3.2M(Jupiter)) orbiting the star V 391 Pegasi at a distance of about 1.7 astronomical units (au), with a period of 3.2 years. This star is on the extreme horizontal branch of the Hertzsprung-Russell diagram, burning helium in its core and pulsating. The maximum radius of the red-giant precursor of V 391 Pegasi may have reached 0.7 au, while the orbital distance of the planet during the stellar main-sequence phase is estimated to be about 1 au. This detection of a planet orbiting a post-red-giant star demonstrates that planets with orbital distances of less than 2 au can survive the red-giant expansion of their parent stars.

4.
Fungal Biol Biotechnol ; 10(1): 2, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36647105

RESUMO

BACKGROUND: Oleaginous fungi have versatile metabolism and able to transform a wide range of substrates into lipids, accounting up to 20-70% of their total cell mass. Therefore, oleaginous fungi are considered as an alternative source of lipids. Oleaginous fungi can accumulate mainly acyl glycerides and free fatty acids which are localized in lipid droplets. Some of the oleaginous fungi possessing promising lipid productivity are dimorphic and can exhibit three cell forms, flat hyphae, swollen hyphae and yeast-like cells. To develop sustainable targeted fungal lipid production, deep understanding of lipogenesis and lipid droplet chemistry in these cell forms is needed at multiscale level. In this study, we explored the potential of infrared spectroscopy techniques for examining lipid droplet formation and accumulation in different cell forms of the dimorphic and oleaginous fungus Mucor circinelloides. RESULTS: Both transmission- and reflectance-based spectroscopy techniques are shown to be well suited for studying bulk fungal biomass. Exploring single cells with infrared microspectroscopy reveals differences in chemical profiles and, consequently, lipogenesis process, for different cell forms. Yeast-like cells of M. circinelloides exhibited the highest absorbance intensities for lipid-associated peaks in comparison to hyphae-like cell forms. Lipid-to-protein ratio, which is commonly used in IR spectroscopy to estimate lipid yield was the lowest in flat hyphae. Swollen hyphae are mainly composed of lipids and characterized by more uniform distribution of lipid-to-protein concentration. Yeast-like cells seem to be comprised mostly of lipids having the largest lipid-to-protein ratio among all studied cell forms. With infrared nanospectroscopy, variations in the ratios between lipid fractions triglycerides and free fatty acids and clear evidence of heterogeneity within and between lipid droplets are illustrated for the first time. CONCLUSIONS: Vibrational spectroscopy techniques can provide comprehensive information on lipogenesis in dimorphic and oleaginous fungi at the levels of the bulk of cells, single cells and single lipid droplets. Unicellular spectra showed that various cell forms of M. circinelloides differs in the total lipid content and profile of the accumulated lipids, where yeast-like cells are the fatty ones and, therefore, could be considered as preferable cell form for producing lipid-rich biomass. Spectra of single lipid droplets showed an indication of possible droplet-to-droplet and within-droplet heterogeneity.

5.
Tissue Antigens ; 79(4): 249-62, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22329842

RESUMO

Folding around a peptide ligand is integral to the antigen presentation function of major histocompatibility complex (MHC) class I molecules. Several lines of evidence indicate that the broadly cross-reactive 34-1-2 antibody is sensitive to folding of the MHC class I peptide-binding groove. Here, we show that peptide-loading complex proteins associated with the murine MHC class I molecule K(d) are found primarily in association with the 34-1-2(+) form. This led us to hypothesize that the 34-1-2 antibody may recognize intermediately, as well as fully, folded MHC class I molecules. To further characterize the form(s) of MHC class I molecules recognized by 34-1-2, we took advantage of its cross-reactivity with L(d) . Recognition of the open and folded forms of L(d) by the 64-3-7 and 30-5-7 antibodies, respectively, has been extensively characterized, providing us with parameters against which to compare 34-1-2 reactivity. We found that the 34-1-2(+) L(d) molecules displayed characteristics indicative of incomplete folding, including increased tapasin association, endoplasmic reticulum retention, and instability at the cell surface. Moreover, we show that an L(d) -specific peptide induced folding of the 34-1-2(+) L(d) intermediate. Altogether, these results yield novel insights into the nature of MHC class I molecules recognized by the 34-1-2 antibody.


Assuntos
Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/metabolismo , Complexo Principal de Histocompatibilidade/fisiologia , Animais , Anticorpos Monoclonais/metabolismo , Western Blotting , Cristalografia por Raios X , Citometria de Fluxo , Glicosilação , Células HeLa , Humanos , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Peptídeos/química , Peptídeos/fisiologia , Dobramento de Proteína , Estabilidade Proteica
6.
Osteoarthr Cartil Open ; 4(2): 100250, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36475284

RESUMO

Objective: To evaluate the feasibility of Fourier transform infrared attenuated total reflectance (FTIR-ATR) spectroscopy to detect cartilage degradation due to osteoarthritis and to validate the methodology with osteochondral human cartilage samples for future development towards clinical use. Design: Cylindrical (d â€‹= â€‹4 â€‹mm) osteochondral samples (n â€‹= â€‹349) were prepared from nine human cadavers and measured with FTIR-ATR spectroscopy. Afterwards, the samples were assessed with Osteoarthritis Research Society International (OARSI) osteoarthritis cartilage histopathology assessment system and divided into two groups: 1) healthy (OARSI 0-2) and 2) osteoarthritic (OARSI 2.5-6). The classification was done with partial least squares discriminant analysis model utilizing cross-model validation. Receiver operating characteristics curve analysis was performed and the area under curve (AUC) was calculated. Results: For all samples combined, classification accuracy was 73% with AUC of 0.79. Femoral samples had accuracy of 74% and AUC of 0.77, while tibial samples had accuracy of 66%, and AUC of 0.74. Patellar samples had accuracy of 84% and AUC of 0.91. Conclusions: The results indicate that FTIR-ATR spectroscopy can differentiate between healthy and osteoarthritic femoral, tibial and patellar human tissue. If combined with a fiber optic probe, FTIR-ATR spectroscopy could provide additional objective intraoperative information during arthroscopic surgeries, which could improve clinical outcomes.

7.
Int J Immunogenet ; 36(3): 183-7, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19490214

RESUMO

Tapasin is a key molecule in the major histocompatibility complex (MHC) class I peptide-loading complex, interacting with several other proteins in the complex. An amino acid substitution at a free cysteine position in tapasin has been shown to disrupt the covalent association of tapasin with ERp57. In this study, we mutated the free cysteine in mouse tapasin, and analysed the effects on the cell surface expression of the mouse MHC class I molecules K(d) and K(b). The C95S substitution in mouse tapasin increased the proportion of open forms relative to folded forms for both types of MHC class I molecules at the cell surface. Furthermore, the C95S substitution resulted in increased association of tapasin with folded K(d). Overall, our studies with these mouse MHC class I allotypes have revealed that the free cysteine 95 in mouse tapasin influences stable expression at the plasma membrane for both MHC class I allotypes, and have shown that tapasin's interaction with folded K(d) is elevated by the C95S substitution in tapasin.


Assuntos
Substituição de Aminoácidos/genética , Antígenos de Histocompatibilidade Classe I/metabolismo , Proteínas de Membrana Transportadoras/genética , Proteínas Mutantes/genética , Substituição de Aminoácidos/fisiologia , Animais , Linhagem Celular , Fibroblastos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Camundongos , Camundongos Knockout , Proteínas Mutantes/metabolismo
8.
Cancer Gene Ther ; 14(4): 364-71, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17235356

RESUMO

Dendritic cell (DC) expansion is regulated by the hematopoietic growth factor fms-like tyrosine kinase 3 ligand (Flt3L). DCs are critical to the control of tumor growth and metastasis, and there is a positive correlation between intratumoral DC infiltration and clinical outcome. In this report, we first demonstrate that single intravenous (i.v.) injections of adenovirus (Adv)-Flt3L significantly increased splenic dendritic, B, T and natural killer (NK) cell numbers in both normal and mammary tumor-bearing mice. In contrast, the numbers of DCs and T cells infiltrating the tumors were not increased. Consistent with the minimal effect on immune cell infiltration, i.v. Adv-Flt3L injections had no therapeutic activity against orthotopic mammary tumors. In addition, we noted tumor and Adv-Flt3L expansion of Gr1(+)CD11b(+) immature myeloid suppressor cells (IMSCs), which may inhibit the therapeutic efficacy of Adv-Flt3L-expanded DCs.


Assuntos
Terapia Genética , Neoplasias Mamárias Animais/terapia , Proteínas de Membrana/genética , Baço/imunologia , Linfócitos T/imunologia , Adenoviridae/genética , Animais , Células Dendríticas/imunologia , Feminino , Vetores Genéticos/administração & dosagem , Vetores Genéticos/genética , Injeções Intravenosas , Contagem de Linfócitos , Linfócitos do Interstício Tumoral/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Falha de Tratamento
9.
Biochim Biophys Acta ; 1402(1): 17-28, 1998 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-9551082

RESUMO

Proteasomes generate peptides from intracellular endogenous and viral proteins for presentation by MHC class I molecules. During viral infection, interferon-gamma (IFN-gamma) acts as a cytokine altering the catalytic specificity of proteasomes by inducing the synthesis of the three proteasome subunits, low molecular weight protein (LMP) 2, LMP7 and multicatalytic endopeptidase complex-like 1 (MECL1). LMP2 and LMP7 have been shown to favour the presentation of certain antigenic peptides. These subunits are constitutively expressed in cell lines related to the immune system and IFN-gamma-inducible in other cell lines. Less is known about MECL1. To reveal the extent of constitutive and IFN-gamma-induced expression of MECL1, we studied MECL1 in different cell lines by Northern and Western blotting. The two B cell lines IM9 and Reh showed high constitutive expression of MECL1, only slightly induced by IFN-gamma stimulation. The B cell line Daudi and the monocyte cell line THP-1 expressed MECL1 constitutively at an intermediate level. The MECL1 protein level in the THP-1 cells increased markedly in response to IFN-gamma. In cells unrelated to the immune system, a very low constitutive expression of MECL1 was detected, highly inducible by IFN-gamma. These results indicate that, similar to LMP2 and LMP7, MECL1 is constitutively expressed at high levels only in certain cell lines and can be induced by IFN-gamma in other cell lines. The differential expression of MECL1 may be of importance for which antigenic peptides are presented by different cells as well as by the same cells at different IFN-gamma levels.


Assuntos
Cisteína Endopeptidases/biossíntese , Cisteína Endopeptidases/genética , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Interferon gama/farmacologia , Complexos Multienzimáticos/biossíntese , Regiões Promotoras Genéticas , Adenocarcinoma , Sequência de Aminoácidos , Linfócitos B/enzimologia , Linfócitos B/imunologia , Sequência de Bases , Neoplasias da Mama , Neoplasias do Colo , Cisteína Endopeptidases/química , DNA/sangue , Éxons , Feminino , Biblioteca Gênica , Células HeLa , Humanos , Íntrons , Leucócitos/metabolismo , Substâncias Macromoleculares , Dados de Sequência Molecular , Complexo de Endopeptidases do Proteassoma , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Mapeamento por Restrição , Transcrição Gênica , Transfecção , Células Tumorais Cultivadas
10.
Mol Immunol ; 24(2): 197-200, 1987 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3614211

RESUMO

Nucleotide sequence analysis of mRNA from the class I murine MHC mutant H-2Kkml has established a site of mutation to be at the codon for amino acid position 152. Complete sequence information for the nucleotides coding for amino acids 136-163 demonstrates an A----C alteration at the codon for amino acid 152, changing Asp (GAT) in Kk to Ala (GCT) in Kkml. Several other murine and human class I MHC variants have similar alterations at amino acid position 152, resulting in altered biological activity. Finally, the pH-2III pseudogene of the H-2k haplotype has a GCT codon at amino acid position 152, suggesting that the GCT codon occurring in Kkml is the result of a gene conversion event.


Assuntos
Antígenos H-2/genética , RNA Mensageiro/genética , Animais , Sequência de Bases , Eletroforese em Gel de Poliacrilamida , Camundongos , Camundongos Endogâmicos CBA , Mutação
11.
Mol Immunol ; 25(3): 267-74, 1988 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-3374494

RESUMO

Nucleotide sequence analysis of mRNA from the H-2K locus of the CBA.M523 mouse, which has the class I murine MHC mutation H-2Kkml, has established the only alteration to be at the codon for amino acid position 152 as compared to the sequence of standard Kk from both the AKR and CBA inbred mouse lines. Complete sequence information for the nucleotides coding for amino acids 1-292, which includes all of the extracellular protein domains, demonstrated an A----C alteration in the codon for amino acid 152 as compared to the standard Kk sequence, changing Asp (GAT) in Kkml. The GCT codon occurring in Kkml may be the result of a gene conversion in Kkml. The GCT codon occurring in Kkml may be the result of a gene conversion event because a potential donor gene, the pH-2III pseudogene of H-2k, is transcribed in the CBA.M523 mouse and has a GCT codon at amino acid position 152. This sequence information obtained for Kkml also demonstrates that Kk gene transcripts from two genetically distinct inbred mouse lines, CBA and AKR, are completely identical. Finally, several other murine and human class I MHC variants have similar alterations at amino acid position 152 which result in altered biological functions. This information suggests that amino acid 152 is an important part of a T-cell-recognized antigenic determinant on MHC class I antigens.


Assuntos
Genes MHC Classe I , Mutação , RNA Mensageiro/genética , Animais , Sequência de Bases , Eletroforese em Gel de Poliacrilamida , Camundongos , Camundongos Endogâmicos CBA , Dados de Sequência Molecular
12.
Mol Immunol ; 32(7): 531-40, 1995 May.
Artigo em Inglês | MEDLINE | ID: mdl-7783756

RESUMO

Newly synthesized class I heavy chains achieve domain structure using disulfide bonds, assemble with beta-2 microglobulin (beta 2m), and bind peptide ligand to complete the trimeric complex. Although each of these initial events is thought to be critical for class I folding, their sequential order and effect on class I structure are unknown. Using mAb specific for distinct conformations of H-2Ld and Lq, we have defined folding intermediates of class I molecules. We show here that non-peptide-associated forms of Ld or Lq, detected by mAb 64-3-7 and designated L alt, lack numerous conformational epitopes surrounding their ligand binding sites. These results support the notion that L alt molecules have an open conformation. Interestingly, a significant proportion of L alt molecules were detected in association with beta 2m and these L alt/beta 2m heterodimers were preferentially folded by peptide in cell lysates. These findings indicate that class I heavy chain/beta 2m association can precede ligand binding and that peptide is probably the limiting factor for completion of the Ld/beta 2m/peptide trimeric complex in vivo. The characteristics of L alt molecules were investigated further by ascertaining the disulfide bond status of these molecules and their association with beta 2m and peptide. Treatment of cells with dithiothreitol (DTT), a membrane-permeable reducing agent, demonstrated that L alt molecules constitute a heterogeneous population including reduced, partially reduced and native class I molecules. Furthermore, partially reduced Ld alt molecules, in a cell line expressing a mutant Ld molecule lacking the alpha 2 domain disulfide bond, accumulated intracellularly, were not beta 2m-associated and displayed marginal peptide-induced folding in vitro. In accordance with this latter finding, peptide was found to preferentially convert fully disulfide-bonded forms of Ld alt to conformed Ld. Thus, we propose that intrachain disulfide bond formation precedes the association of class I heavy chain with beta 2m and peptide, and that disulfide bond formation is required for efficient assembly, ligand binding and folding of the class I heavy chain.


Assuntos
Antígenos H-2/química , Peptídeos/imunologia , Microglobulina beta-2/imunologia , Animais , Anticorpos Monoclonais , Sequência de Bases , Linhagem Celular , DNA Complementar/genética , Dissulfetos/química , Antígenos H-2/genética , Antígenos H-2/metabolismo , Antígeno de Histocompatibilidade H-2D , Camundongos , Modelos Moleculares , Dados de Sequência Molecular , Estrutura Molecular , Mutagênese Sítio-Dirigida , Peptídeos/metabolismo , Ligação Proteica , Conformação Proteica , Dobramento de Proteína , Microglobulina beta-2/metabolismo
13.
FEBS Lett ; 309(3): 307-10, 1992 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-1516702

RESUMO

Three of the original Norwegian lecithin:cholesterol acyltransferase (LCAT) deficiency families have been investigated for mutations in the gene for lecithin:cholesterol acyltransferase by DNA sequencing of the exons amplified by the polymerase chain reaction. A single T----A transversion in codon 252 in exon 6 converting Met(ATG) to Lys(AAG) was observed in all homozygotes. In spite of the identical mutation, the disease phenotypes differed in severity. This was not reflected in the expression of LCAT in the heterozygotes.


Assuntos
Deficiência da Lecitina Colesterol Aciltransferase/genética , Feminino , Humanos , Masculino , Mutação , Noruega , Fosfatidilcolina-Esterol O-Aciltransferase/metabolismo , Reação em Cadeia da Polimerase
14.
Immunol Res ; 14(3): 200-17, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8778210

RESUMO

Assembly of the class I MHC molecule is inextricably linked to the antigen presentation function of the class I molecule. Association of the class I MHC molecule with beta 2-microglobulin (beta 2m) is a prerequisite for association with the heterodimeric protein TAP, and once peptide is acquired, the class I molecule folds and begins its sojourn to the cell surface. To maintain its folded conformation, class I MHC requires peptide but not beta 2m, and the sequence of the peptide bound exercises a subtle influence on the structure of the class I molecule that is likely to be a factor in T cell receptor discrimination of MHC/peptide complexes.


Assuntos
Antígenos de Histocompatibilidade Classe I/biossíntese , Antígenos de Histocompatibilidade Classe I/química , Microglobulina beta-2/imunologia , Animais , Apresentação de Antígeno , Proteínas de Ligação ao Cálcio/metabolismo , Calnexina , Camundongos , Modelos Imunológicos , Modelos Moleculares , Peptídeos/imunologia , Conformação Proteica , Dobramento de Proteína
15.
Artigo em Inglês | MEDLINE | ID: mdl-15180455

RESUMO

Fms-like tyrosine kinase 3 ligand (Flt3L) has multiple effects on the hematopoietic and immune systems. Further, preclinical studies have suggested potential therapeutic activity against cancer. Flt3L is a potent hematopoietic cytokine, capable of stimulating the expansion and differentiation of hematopoietic progenitor and stem cells. Administration of Flt3L mobilizes hematopoietic cells from the bone marrow (BM) into the blood, lymphoid organs, and parenchymal tissues. This mobilization activity, especially effective in combination with granulocyte colony stimulating factor (G-CSF), has stimulated studies of Flt3L in hematopoietic stem cell (HSC) transplantation. In addition to its effects on hematopoietic stem and progenitor cells, Flt3L has been shown to increase the frequency and number of dendritic cells (DCs) within the circulatory system and solid organs. DC expansion by Flt3L has been the focus of preclinical and clinical studies on antigen (Ag) specific T-cell mediated immunity. The mechanism for the augmentation of T-cell mediated immunity has yet to be completely identified, although Flt3L's ability to expand DCs in lymphoid and non-lymphoid tissues is involved. This expansion occurs primarily with DCs, which secrete interleukin (IL) 12. Consistent with the expansion of this DC population, treatment with Flt3L enhances T-cell mitogenesis and preferentially induces type 1 T-cell responses. However, the DCs resulting from Flt3L administration are immature, leading in some studies to the induction of tolerance. This review focuses on the effects of Flt3L on DCs and other effector populations, and on its potential activity as a therapeutic agent for cancer, alone and in combination with vaccines.


Assuntos
Vacinas Anticâncer/metabolismo , Vacinas Anticâncer/uso terapêutico , Proteínas de Membrana/metabolismo , Proteínas de Membrana/uso terapêutico , Proteínas Proto-Oncogênicas/fisiologia , Receptores Proteína Tirosina Quinases/fisiologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/fisiologia , Adjuvantes Imunológicos/uso terapêutico , Animais , Vacinas Anticâncer/administração & dosagem , Ligantes , Proteínas de Membrana/administração & dosagem , Proteínas de Membrana/fisiologia , Tirosina Quinase 3 Semelhante a fms
16.
Intensive Care Med ; 16(1): 69-72, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2312909

RESUMO

A 51-year-old male remained immersed in sea water (6 degrees C) for 40 min. Brought ashore, the ECG showed asystole. Advanced life support was immediately commenced. On arrival in hospital his rectal temperature was 27 degrees C, but continued to fall to 24 degrees C. The ECG remained isoelectric. Cardiopulmonary resuscitation was continued until extracorporeal circulation was established 190 min after rescue. Upon rewarming ventricular fibrillation occurred which was converted to sinus rhythm with a bolus of lignocaine followed by D.C. conversion at 31.5 degrees C. When rewarming was complete after 60 min, signs of severe heart failure became evident. Sternotomy and pericardiotomy were performed to exclude cardiac tamponade. After 60 min of re-perfusion the patient was be weaned from bypass supported by a high-dose vasopressor infusion and nitroglycerine. He was discharged after 13 days with no evidence of any permanent organ damage. Given the advantage of providing circulatory support, extracorporeal circulation may be useful when rewarming hypothermic victims with cardiac arrest.


Assuntos
Circulação Extracorpórea , Parada Cardíaca/complicações , Hipotermia/terapia , Imersão/efeitos adversos , Parada Cardíaca/etiologia , Parada Cardíaca/terapia , Humanos , Hipotermia/sangue , Hipotermia/etiologia , Masculino , Pessoa de Meia-Idade
17.
DNA Seq ; 1(4): 227-32, 1991.
Artigo em Inglês | MEDLINE | ID: mdl-1806039

RESUMO

Plasmid DNA released from bacteria by boiling in the presence of lysozyme and Triton x-100 and without further purification can be sequenced by the dideoxy method using T7 DNA polymerase, when conditions during alkali denaturation and subsequent ethanol precipitation are adjusted to remove contaminants. The samples remain in the same microcentrifuge tubes from the harvesting of the bacteria until the splitting of the sample into four aliquots for the termination reactions. Less background label is observed with end-labelled primers (radioactivity or fluorescence), but even when radioactive nucleotides are incorporated during the sequencing reactions, 250 bases or more can be read from template prepared from 1.5 ml bacterial culture. The DNA can also be cut by restriction enzymes; the purification procedure described thus provides the rapid preparation of plasmids for a variety of purposes.


Assuntos
Sequência de Bases , DNA , Plasmídeos , DNA/genética , Fluorescência , Técnicas Genéticas , Humanos , Desnaturação de Ácido Nucleico , Fosfatidilcolina-Esterol O-Aciltransferase/genética
18.
Child Abuse Negl ; 6(2): 147-54, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6892295

RESUMO

It appears that Sweden and the United States may be a study in contrasts regarding the sanction and use of corporal punishment on children. A 1979 study of American parents noted that 81% of them employed corporal punishment with children. A different study done in Sweden in 1978 noted that only 26% of parents used corporal punishment with children. What points to the differences in these parenting patterns within the two countries? In addition, a 1977 U.S. Supreme Court case entitled Ingraham vs. Wright ruled that "schools are empowered to carry out corporal punishment." This court case involved two high school boys in Florida who had been repeatedly struck with wooden paddles. In contrast, Sweden had statutes which prohibited corporal punishment of children in their secondary schools as early as the 1920s. In 1957, the country passed a law which defined corporal punishment as unacceptable for small children in the schools. Then, in 1979, the Swedish government passed a statute prohibiting corporal punishment by parents. Are there differences in the way the two countries view law and its uses? Or, do the cultures sanction violence in general or just violence against children in different ways? This article examines some of the similarities and differences found in American and Swedish treatment of children and proposes what appear to be extreme differences in the way the countries and their people approach corporal punishment.


Assuntos
Educação Infantil , Comparação Transcultural , Pais , Punição , Criança , Maus-Tratos Infantis , Humanos , Suécia , Estados Unidos
20.
Immunol Rev ; 172: 11-9, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10631933

RESUMO

Several years ago, the only factor known to be necessary for the assembly and surface expression of class I MHC was beta 2m; even for beta 2m, it was unclear at what point in class I maturation its role was played. Recent experiments that employed attachment of an endoplasmic reticulum (ER) retention signal to beta 2m have shown that the point of time at which beta 2m is required is while the class I heavy chain is in the ER. Later association between beta 2m and class I is not vital in order for properly folded class I to be expressed at the cell surface. After crystallization of the first class I MHC molecule, it was realized that not only is antigen presented by class I, but that antigen is presented in the form of a peptide that stabilizes the class I structure and allows its transit to the cell surface. Class I allelic differences influence interactions with both peptide and beta 2m, with likely consequences for the ability of the class I heavy chains to present antigen through alternative pathways. Furthermore, it is now also clear that formation of appropriate disulfide bonds in the class I heavy chain is needed before class I can bind peptide antigen securely, a process that may be assisted by an ER chaperone. Many different proteins that are resident in the ER, such as calnexin, transporter associated with antigen processing (TAP), calreticulin, and tapasin, have been found to be integral to class I assembly. TAP, tapasin, and calreticulin bind preferentially to the open form of class I, which can be distinguished with the use of a monoclonal antibody specific for this form. Calreticulin and calnexin contrast in their interactions with class I, despite other similarities between these two chaperones. Overall, class I MHC assembly is now understood to involve the interplay of multiple intra- and intermolecular events in a defined chronological order which ensure continual reporting of cellular contents to cytotoxic T lymphocytes.


Assuntos
Apresentação de Antígeno , Antígenos de Histocompatibilidade Classe I/química , Antígenos de Histocompatibilidade Classe I/metabolismo , Alelos , Animais , Antiporters/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Calnexina , Calreticulina , Retículo Endoplasmático/imunologia , Retículo Endoplasmático/metabolismo , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Imunoglobulinas/metabolismo , Substâncias Macromoleculares , Proteínas de Membrana Transportadoras , Modelos Moleculares , Conformação Proteica , Ribonucleoproteínas/metabolismo , Microglobulina beta-2/metabolismo
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