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61.
Immunotherapy by adoptive transfer of autologous tumour-infiltrating lymphocytes (TIL) shows promising clinical results for stage III (lymph nodes metastasis) melanoma patients, but some of them remain unresponsive. Here we analysed retrospectively the impact of resistance of melanoma cells to anti-proliferative cytokines on the clinical outcome of 24 TIL-treated metastatic melanoma patients. Patient relapse-free survival correlated significantly with Oncostatin M (OSM) and/or IL-6 sensitivity of melanoma cells, but not with interferon (IFN) gamma or tumour necrosis factor (TNF) alpha sensitivity. However, OSM/IL-6 sensitivity did not correlate with other known prognostic factors. Moreover, OSM and IL-6 were produced by TIL just before their injection to patients. In immunodeficient mice, OSM reduced human melanoma xenograft tumour growth, this effect being directly through inhibition of tumour cell proliferation rather than induction of apoptosis or necrosis. Thus, OSM/IL-6 resistance of melanoma cells appears to be a new escape mechanism to TIL treatment that could be added to the existing prognostic factors for early stage melanoma patients. This mechanism of action could be also relevant in other immunotherapy protocols, and could lead to better prognosis and anti-cancer treatments.  相似文献   
62.
BACKGROUND: The elucidation of the molecular mechanisms by which the embryo contributes to its implantation is an area of extensive research. The main objective of this study was to investigate the pattern of leukemia inhibitory factor (LIF) and interleukin-6 (IL-6) secretion by human endometrial epithelium, and their regulation by human chorionic gonadotropin (hCG) and other growth factors present at the embryonic-endometrial interface. METHODS: Endometrial epithelial cells (EEC) were isolated from biopsies collected at both proliferative and secretory phases of fertile women. RESULTS: HCG (1-50 IU/ml) increased LIF secretion by EEC cultures derived from follicular phase (up to 285+/-75%) or from secretory phase (up to 212+/-16%). In contrast, hCG reduced IL-6 secretion by EEC in both phases. The hCG/LH receptor gene was transcribed by EEC as evidenced by RT-PCR. Insulin-like growth factors 1 and 2 increased LIF secretion by EEC. Transforming growth factor beta1 stimulated LIF and reduced IL-6 secretion. CONCLUSIONS: Through hCG, the blastocyst may be involved in the control of its implantation (via an increase of proimplantatory LIF) and tolerance (via an inhibition of proinflammatory IL-6). Other growth factors present at the embryonic-endometrial interface are also involved in the control of LIF and IL-6 endometrial secretion.  相似文献   
63.
64.
BACKGROUND: Naevus of Ota manifests various colours ranging from light brown to blue. Naevus colours have been claimed to reflect the depth of melanin pigments but the claim has rarely been substantiated by quantitative studies. OBJECTIVES: We attempted both quantitative and qualitative analyses of the naevus of Ota to find out relations between histological patterns or parameters of melanin/melanocytes and lesion colours. METHODS: Lesion colours were determined by one of the authors and were confirmed by a separate panel of dermatologists. Forty biopsy specimens of naevus of Ota were evaluated by both computer-assisted quantitative image analysis and a previously proposed conventional pattern analysis. RESULTS: The mean area fraction (AFmean) of melanin, the depth of the maximum area fraction of melanin (level of AFmax) and the depth of the deepest infiltrating melanocyte were significantly greater or deeper for bluish lesions than brownish lesions. Based on the qualitative pattern analysis we found that all the brownish lesions demonstrated superficial dermal melanin pigments, whereas bluish lesions tended to show more heterogeneous histological patterns. Eyelid lesions, all of which were bluish, revealed greater AF(mean) value than cheek lesions, presenting as either brownish or bluish colours. CONCLUSIONS: Quantitative analysis indicated that pigment density measures such as AFmean could be as important as the depth of melanocytes in the explanation of the lesion colours in naevus of Ota. However, qualitative pattern analysis failed to link specific patterns with lesion colours, especially in bluish lesions, probably due to the lack of consideration of the pigment density.  相似文献   
65.
BACKGROUND: Peripheral neuropathies (PN) associated with monoclonal gammopathy (MG) are widely considered as autoimmune disorders, but the putative role of incriminated antigens is still not understood. OBJECTIVE: Fifty five patients with PN associated with MG were studied to investigate whether new antigens could be found, and to evaluate their relation to clinical manifestations. METHODS: An immunological study was conducted on patient sera to identify autoreactivities against nerve proteins by western blotting. Antigen proteins were purified and analysed by proteomic tools. Correlation with ultrastrucural and clinical features was then studied. RESULTS: Of the 55 patients suffering from PN associated with MG, 17 exhibited IgG autoantibodies directed against peripheral nerve proteins of 35, 58, and 60 kDa. N-terminal microsequencing and mass spectrometry analyses of the 35 kDa protein revealed perfect peptidic matching with 47% of the amino acid sequence of P0, whereas the 58 and 60 kDa proteins were identified as the reduced and non-reduced forms of a P0 dimer. Deglycosylation did not affect IgG binding to the 35 kDa P0 related protein, suggesting a peptidic epitope. In contrast, deglycosylation abolished IgG recognition of the P0 dimer protein, so that a carbohydrate moiety may be implicated in the epitope formation. This confirmed the existence of two different types of IgG, one recognising the 58 and 60 kDa proteins and one directed against the 35 kDa protein. CONCLUSIONS: This is the first report of antibody activity directed against the dimeric association of P0. Although P0 oligomerisation and adhesion properties play a crucial part in the myelin sheath compaction, the pathogenic significance of these autoantibodies needs further investigations to be elucidated.  相似文献   
66.
In this study, we compared the effects of chronic ultramild stress (CUMS) exposure on decision-making behavior in a validated test, and on the stress responsive serotoninergic and dopaminergic systems in four age groups of B6D2F1 female mice (5-6, 11-12, 17-18 and 23-24 months old). The levels of serotonin (5-HT) and its metabolite 5-hydroxyindolacetic acid (5-HIAA) were measured in the brain stem, the cortex, the striatum and the hippocampus; the levels of dopamine (DA) and its metabolite dihydroxyphenylacetic acid (DOPAC) were measured in the brain stem and the striatum. The influence of a long-term treatment with the extract of Ginkgo biloba leaves EGb 761 (Tanakan) on age- and stress-related changes was also investigated in the two oldest age groups. In the absence of drug treatment, middle-age mice were the least efficient in making a decision, and senescent mice exhibited reduced levels of both 5-HT and DA and their metabolites in all the brain areas examined. CUMS facilitated evaluation and choice behavior in all age groups, but induced age-dependent reduction of hesitation, acceleration of information processing and reduction in serotoninergic neurotransmission. In senescent mice, EGb 761 reduced the impact of stress on evaluation and hesitation, and restored some stress-related neurobehavioral changes that were only seen in young mice, i.e. acceleration of information processing and reduction in brain 5-HIAA levels. Restoration of some plasticity of the serotoninergic systems might contribute to the stress alleviating influence of EGb 761 in old age.  相似文献   
67.
Aims: To identify a DNA methylation signature of endometrioid carcinoma of the endometrium (EEC) in the early stages of endometrial carcinogenesis. Methods and results: Archival biopsy specimens of 39 EECs, 14 cases of atypical hyperplasia (AH), 11 histologically normal endometrial tissues adjacent to EECs and 24 normal control endometrial samples were retrieved. The cases were tested by quantitative methylation‐specific polymerase chain reaction with primers hybridizing in the promoter regions of five genes frequently methylated in human cancer (RASSF1A, RARb2, P16, MGMT and GSTPi). Twenty‐nine of 39 (74%) EECs and 7/14 (50%) AHs were methylated for the RASSF1A gene, whereas 17/39 (44%) EECs and 6/14 (43%) AHs were positive for the methylation of the RARb2 gene. No significant results were obtained for the other genes (P16, MGMT and GSTPi). Interestingly, 4/11 (36%) and 6/11 (55%) histologically normal endometrial tissues adjacent to EEC showed, respectively, RASSF1A and RARb2 gene methylation. Furthermore, these 11 specimens were microsatellite stable and showed similar proliferative, cell cycle and apoptotic mean labelling indices as the normal endometrial control tissues. Conclusions: Promoter region methylation of RASSF1A and RARb2 genes is an early event in endometrial carcinogenesis.  相似文献   
68.

Objectives

An amendment to the French bioethics law allowing children conceived by gamete donation to know the identity of donors is proposed, while no study can assess the proportion of parents in France that disclose the nature of conception to their donor conceived offspring. The aim of our study was to know whether couples who wish to inform their offspring actually did it.

Patients and methods

We sent a questionnaire to parents who had expressed an intention to disclose the nature of conception to their future offspring conceived by sperm donation. This allowed us to evaluate the number of couples who inform their offspring, and the couple and offspring feelings when information was given.

Results

Among 38 questionnaires sent, 20 couples answered. Fourteen informed their offspring about the nature of conception, most having lived serenely this moment. 47% of offspring have reacted with indifference. While 19 couples informed their friends or family, six couples did not inform their offspring, and two of them no longer want to disclose anymore.

Conclusion

Careful thought before the beginning of assisted reproductive technology and support after birth are needed to help couples communicate information to their offspring. Without this communication, any policy of openness to know donor related data seems vain.  相似文献   
69.
A case of uterine torsion in a 37-years-old woman during twin pregnancy is described. Diagnosis was made during caesarean section and the torsion successfully reduced through a standing laparotomy. Detorsion was accomplished by rotating the uterus to the left. A severe post-partum haemorrhage occurred and hysterectomy was required. The patient recovered and was discharged home with her baby. Uterine torsion at term is a rare obstetric event that occurs mainly in the third trimester with adverse maternal and neonatal consequences and raises several critical management considerations. We review possible diagnostic signs and management of this rare complication from literature.  相似文献   
70.

Objective

Animal models of asthma mimic major features of human disease. Since the genetic background of experimental animals might affect hyperresponsiveness and inflammation, we studied its potential influence and the mechanisms leading to differences in strains.

Methods

We applied a mouse model of allergic asthma to BALB/c and C57BL/6 mice.

Results

BALB/c mice displayed greater levels of airway reactivity to methacholine than C57BL/6 mice. Moreover, BALB/c mice exhibited higher numbers of mast cells in lung tissue when compared to C57BL/6. On the contrary, eosinophil and neutrophil counts in bronchoalveolar lavage fluid (BALF) as well as peribronchial eosinophilia were greater in C57BL/6. IL (Interleukin)-4, IL-5, IL-13, and CCL11 levels measured in whole-lung extracts were higher in BALB/c, while, in sharp contrast, CCL11 and CCL5 levels were higher in BALF of C57BL/6 mice.

Conclusions

We observed phenotypic differences between C57BL/6 and BALB/c mice in an asthma model with different distributions of pro-inflammatory cytokines and inflammatory cells.  相似文献   
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