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121.
Kinetics of the phenotype and function of murine peritoneal macrophages following acute inflammation 总被引:2,自引:0,他引:2
Wu Q Feng Y Yang Y Jingliu Zhou W He P Zhou R Li X Zou J 《Cellular & molecular immunology》2004,1(1):57-62
This study was undertaken to have a better understand for the process and the underlying mechanisms to limitmacrophage activation and population of activated macrophages.A comprehensive kinetics of cytokineproduction was performed in murine peritoneal macrophages recovered from Balb/c mice at various timeduring the course of an intraperitoneal injection with thioglycollate (TG).The expression of cell surfacemolecules such as MHC-Ⅰ,MHC-Ⅱ,B7-1 and B7-2 of these macrophages were also determined by flowcytometry.The present findings of our research suggested that the population of activated macrophages and theactivation of macrophages (including cytokines production and expression of cell surface functional molecules)were strictly controlled during inflammation process.This is one of the important mechanisms to retain the hosthomeostasis.Cellular & Molecular Immunology.2004;1(1):57-62. 相似文献
122.
Monoclonal antibodies recognizing EVETPIRN epitope of influenza A virus M2 protein could protect mice from lethal influenza A virus challenge 总被引:8,自引:0,他引:8
Based on the fact that the 24 amino acid extracellular domain of M2 protein (M2e) is nearly invariant in all influenza A strains, several different M2e vaccine constructs and vaccination modalities have been developed by others and us. Although most of these vaccines could induce efficient and broad-spectrum immunity inhibiting influenza A virus infection in mice model, information of the refined protective epitope on M2e was scarce. In this paper, two M2e specific monoclonal antibodies (mAbs) conferring protective immunity in vivo were reported, which in passive administration could protect 75% mice from five LD(50) (50% lethal dose) challenge of influenza virus A/PR/8/34. In addition, higher M2e specific antibody titer (over 1:1600) could be detected after 12h of intraperitoneal passive administration in mice sera. Peptide mapping assay indicated that both mAbs strongly interacted with N-terminus and middle part peptides of M2e (NM2, aa2-12; MM2, aa8-18), but not with the C-terminus peptide (CM2, aa13-24). More importantly, M2e specific mAbs could recognize EVETPIRN (aa6-13) peptide, which were the overlapping region of NM2 and MM2 peptide and the neighboring amino acid residues. In contrast, M2e domain that was deleted EVETPIR sequence could not be recognized by either mAb in immunoblotting assay. All these results indicated that the epitope EVETPIRN (aa6-13) on M2e could be responsible for the induction of the protective immunity. 相似文献
123.
严重急性呼吸综合征患者尸解肺标本的病理改变和致病机制研究 总被引:4,自引:0,他引:4
Pei F Zheng J Gao ZF Zhong YF Fang WG Gong EC Zou WZ Wang SL Gao DX Xie ZG Lu M Shi XY Liu CR Yang JP Wang YP Han ZH Shi XH Dao WB Gu J 《中华病理学杂志》2005,34(10):656-660
目的研究严重急性呼吸综合征(SARS)患者尸解肺标本的病理改变和致病机制。方法观察了2003年4-7月期间死于SARS的6例患者的肺标本,并采用光镜、电镜、Masson三色染色和免疫组织化学染色方法(EnVision法)进行研究。结果肺标本的病理形态改变:(1)6例的双肺均可见到弥漫性实变病灶,肺重量明显增加;(2)6例均可见到弥漫性肺泡损伤,包括透明膜形成、肺泡腔内水肿/出血、纤维素沉积和肺泡上皮细胞脱屑,AE1/AE3免疫组织化学染色显示肺泡上皮细胞的完整性明显破坏;(3)Ⅱ型肺泡上皮细胞轻度增生,有一定异型性,细胞体积增大,胞质呈双染性和颗粒状,胞质内可见小脂肪空泡聚集(5/6);(4)6例中有5例可见巨细胞在肺泡内浸润,巨细胞大多AEl/AE3阳性(5/6),少数CD68阳性(2/6);(5)组织学形态和免疫组织化学染色证实肺泡腔内和肺泡间隔内有多量巨噬细胞浸润(6/6);(6)6例中有5例可见巨噬细胞噬红细胞象;(7)6例中有5例可见肺纤维化,包括肺泡间隔和肺间质增宽(5/6)、肺泡腔内渗出物机化(6/6)和胸膜增厚(4/6)。Masson三色染色证实胶原纤维明显增生,免疫组织化学染色显示大多数为Ⅲ型胶原。光镜和免疫组织化学染色显示5例有明显的成纤维细胞/肌纤维母细胞增生灶;(8)5例可见支气管黏膜鳞状上皮化生;(9)6例患者均可见血栓;(10)2例同时合并其他感染,1例合并细菌感染,另1例合并真菌感染。此外,电镜发现在肺泡上皮细胞和肺血管内皮细胞的胞质内有冠状病毒样颗粒。结论SARS冠状病毒直接损伤肺泡上皮细胞、巨噬细胞明显浸润和成纤维细胞/肌纤维母细胞显著增生在SARS的致病机制中起重要作用。 相似文献
124.
目的 建立检测EBV感染的新方法并观察EBV与鼻咽癌的关系。方法 鼻咽部活检组织和石蜡包埋标本6 6例 ,采用荧光定量聚合酶链反应 (FQ -PCR)和原位杂交 (ISH)两种方法检测EBV ,其检测结果与病理诊断对照。结果 :FQ-PCR检测EBV -DNA阴性 5 2例 ,其中 5 1例为炎性病变 ,另 1例为腺癌 ;EBV -DNA阳性 14例 ,其中 13例为鳞状细胞癌 ,另 1例虽为炎症。但部分上皮细胞呈不典型增生。ISH检测EBV阳性 4 9例 ,其中 4 7例为炎性病变 2例为癌。EBV阳性 17例 ,其中 12例为癌 ,5例为炎性病变。FQ -PCR和ISH检测EBV结果 ,经卡方检测差异无显著性 (P >0 .0 5 )。结论 EBV感染与鼻咽癌有高度相关性。FQ -PCR检测EBV具有方法简单、快速、定量准确等优点。 相似文献
125.
Zou Jian-Ping; Yamamoto Norihiko; Fujii Tetsuya; Takenaka Hiroshi; Kobayashi Michiko; Herrmann Steven H.; Wolf Stanley F.; Fujiwara Hiromi; Hamaoka Toshiyuki 《International immunology》1995,7(7):1135-1145
Unfractionated spleen cells taken from tumor-bearing mice 2weeks after tumor implantation contained tumor-primed T cellswhich produced cytokines including IL-2 and IFN- when culturedin vitro. With progressive tumor growth this initial lymphokine-producingcapacity decreased. Here, we investigated the ability of IL-12to (I) restore suppressed IFN- production, (II) cause tumorregression and (II) induce anti-tumor protective immunity. Additionof rIL-12 to spleen cell cultures from 4- to 10-week-old tumor-bearingmice resulted in a striking enhancement in the production ofIFN- compared with cultures of these cells in the absence ofrIL-12 or of normal spleen cells in the presence of rIL-12.Five I.p. injections of rIL-12 into mice bearing s.c. tumorsinduced complete tumor regression. This was found when rIL-12was given at early (1–2 weeks), intermediate (4–5weeks) or even late (7 weeks) stages of tumor growth. Furthermore,IL-12-treated mice which rejected the primary tumor exhibitedcomplete resistance to a rechallenge with the same tumor butdid not reject a second syngenetic tumor. Immunohistochemicalanalyses following IL-12 treatment revealed that CD4+ and CD8+T cells infiltrate the tumor. More importantly, IFN- mRNA expressionwas observed in fresh tumor masses from tumor-bearing mice receivingIL-12 treatment The importance of IFN- was further demonstratedby the observation that the systemic administration of anti-IFN-mAb prior to IL-12 treatment completely abrogated the anti-tumoreffect of IL-12. Thus, these results indicate that administrationof modest levels of rIL-12 to tumor-bearing mice results intumor regression through mechanisms involving reversal of suppressedIFN- production by anti-tumor T cells and the establishmentof a tumor-specific protective immune response. 相似文献
126.
A new type of polysaccharide host, carboxymethyl-histaminocarbonylmethylamylose ( 2b ), containing carboxylic, imidazolyl and hydroxyl groups in the backbone, was used as a mimetic system for chymotrypsin in the catalytic hydrolysis of 3-acetoxy-N-dodecylpyridinium iodide ( 1 ). The substrate is located in the hydrophobic cavity of the amylose helix. The apparent saturation, the entropy-favored kinetics and the pronounced catalytic efficiency (9 times higher than that of a system consisting of the same concentration of carboxymethylamylose and histamine) show that 2b is a good enzyme model in which the definite binding site, active center and self-organization characteristics are present. Most distinctly, the pH-rate constant profile of the hydrolysis of 1 and 2b is of bell-type and has an optimum at pH 7,98, which is very close to 7,90 for chymotrypsin. In conclusion, the charge relay mechanism is also involved in the catalytic effect of 2b . 相似文献
127.
认知疗法治疗强迫症的对照研究 总被引:2,自引:0,他引:2
目的 探讨认知疗法治疗强迫症的疗效。方法 对 6 0例符合 CCMD-2 -R诊断标准 ,且 Y-BOCS量表评分≥ 1 6分的强迫症病人 ,随机分到认知治疗组 ( 30例 )和氯丙咪嗪组 ( 30例 ) ,两组在氯丙咪嗪常规治疗的同时 ,其中一组加用认知治疗 ,共治疗 8周。在治疗前、后两组均进行临床疗效评估和 Y-BOCS量表评分。结果 认知治疗组痊愈 1 1例、显效 1 6例、有效 3例。氯丙咪嗪组痊愈 6例、显效 1 4例、有效 1 0例。两组痊愈和显效比较有显著差异 ( P<0 .0 5 )。 Y-BOCS量表减分率 :认知治疗组 5 4 .90 % ,氯丙咪嗪组 4 2 .33% ,两组比较有显著差异 ( P<0 .0 5 )。结论 认知疗法配合药物治疗强迫症比单用氯丙咪嗪治疗强迫症疗效更好 相似文献
128.
Mutation spectrum and genotype-phenotype analyses in Cowden disease and Bannayan-Zonana syndrome, two hamartoma syndromes with germline PTEN mutation 总被引:22,自引:1,他引:22
Marsh DJ; Coulon V; Lunetta KL; Rocca-Serra P; Dahia PL; Zheng Z; Liaw D; Caron S; Duboue B; Lin AY; Richardson AL; Bonnetblanc JM; Bressieux JM; Cabarrot-Moreau A; Chompret A; Demange L; Eeles RA; Yahanda AM; Fearon ER; Fricker JP; Gorlin RJ; Hodgson SV; Huson S; Lacombe D; Eng C 《Human molecular genetics》1998,7(3):507-515
The tumour suppressor gene PTEN , which maps to 10q23.3 and encodes a 403
amino acid dual specificity phosphatase (protein tyrosine phosphatase;
PTPase), was shown recently to play a broad role in human malignancy.
Somatic PTEN deletions and mutations were observed in sporadic breast,
brain, prostate and kidney cancer cell lines and in several primary tumours
such as endometrial carcinomas, malignant melanoma and thyroid tumours. In
addition, PTEN was identified as the susceptibility gene for two hamartoma
syndromes: Cowden disease (CD; MIM 158350) and Bannayan-Zonana (BZS) or
Ruvalcaba-Riley-Smith syndrome (MIM 153480). Constitutive DNA from 37 CD
families and seven BZS families was screened for germline PTEN mutations.
PTEN mutations were identified in 30 of 37 (81%) CD families, including
missense and nonsense point mutations, deletions, insertions, a
deletion/insertion and splice site mutations. These mutations were
scattered over the entire length of PTEN , with the exception of the first,
fourth and last exons. A 'hot spot' for PTEN mutation in CD was identified
in exon 5 that contains the PTPase core motif, with 13 of 30 (43%) CD
mutations identified in this exon. Seven of 30 (23%) were within the core
motif, the majority (five of seven) of which were missense mutations,
possibly pointing to the functional significance of this region. Germline
PTEN mutations were identified in four of seven (57%) BZS families studied.
Interestingly, none of these mutations was observed in the PTPase core
motif. It is also worthy of note that a single nonsense point mutation,
R233X, was observed in the germline DNA from two unrelated CD families and
one BZS family. Genotype-phenotype studies were not performed on this small
group of BZS families. However, genotype-phenotype analysis inthe group of
CD families revealed two possible associations worthy of follow-up in
independent analyses. The first was an association noted in the group of CD
families with breast disease. A correlation was observed between the
presence/absence of a PTEN mutation and the type of breast involvement
(unaffected versus benign versus malignant). Specifically and more
directly, an association was also observed between the presence of a PTEN
mutation and malignant breast disease. Secondly, there appeared to be an
interdependent association between mutations upstream and within the PTPase
core motif, the core motif containing the majority of missense mutations,
and the involvement of all major organ systems (central nervous system,
thyroid, breast, skin and gastrointestinal tract). However, these
observations would need to be confirmed by studying a larger number of CD
families.
相似文献
129.
Gonadotrophin-releasing hormone agonist dose-dependency of pituitary desensitization during controlled ovarian hyperstimulation in IVF 总被引:2,自引:2,他引:2
Janssens RM; Vermeiden JP; Lambalk CB; Schats R; Schoemaker J 《Human reproduction (Oxford, England)》1998,13(9):2386-2391
The aim of this study was to find the minimal effective daily s.c. dose of
the gonadotrophin-releasing hormone (GnRH) agonist, triptorelin acetate,
that suppresses the GnRH-induced release of luteinizing hormone (LH) at
time of human chorionic gonadotrophin (HCG) injection and thereby prevents
spontaneous LH surges during in-vitro fertilization (IVF) stimulation
cycles. Therefore, a double-blind, prospective and randomized titration
study was performed. A total of 48 IVF patients were divided into four
groups of 12 patients. Each group received a different dose of triptorelin
acetate, namely 5, 15, 50 or 100 microg s.c. daily. Standard ovarian
stimulation was carried out using urinary follicle stimulating hormone
(FSH) preparations. A 500 microg GnRH test was performed 90 min before the
HCG injection in order to measure the degree of pituitary desensitization.
Spontaneous LH surges were not detected in any of the groups, although
three patients in the 5 microg group had ovulated at the time of ovum
retrieval. The pituitary LH response to the GnRH test at time of HCG,
expressed as area under the curve (AUC), appeared to be dose-dependent.
Thus, a daily s.c. dose of 100 microg triptorelin acetate appears to be too
high, since adequate desensitization of the pituitary (i.e. no spontaneous
LH surge) can be achieved with doses as low as 15 and 50 microg.
相似文献
130.
Bals-Pratsch M; De Geyter C; Muller T; Frieling U; Lerchl A; Pirke KM; Hanker JP; Becker-Carus C; Nieschlag E 《Human reproduction (Oxford, England)》1997,12(5):896-904
Preliminary data have suggested that female infertility due to corpus
luteum insufficiency may be caused by subclinical hypothyroidism
[exaggerated thyroid-stimulating hormone (TSH) response to thyrotrophin-
releasing hormone (TRH) stimulation]. L-Thyroxine supplementation has been
recommended to achieve pregnancies in subclinical hypothyroid women. This
controlled study was carried out in order to investigate the biochemical
diagnosis of subclinical hypothyroidism as a possible infertility factor.
Five infertile patients (aged 25-36 years) with subclinical hypothyroidism
(n = 4, stimulated TSH >20 microU/ml) or primary hypothyroidism (n = 1)
and five healthy controls (aged 22-39 years) with normal thyroid function
(stimulated TSH <15 microU/ml), regular cycles and no history of
infertility were studied in the early follicular phase. In the pre-study
evaluation, eight of 23 volunteers (34.8%) had to be excluded because of
subclinical hypothyroidism with stimulated TSH values (TSHs) >15
microU/ml. Cycle function of patients and controls was compared by the
method of LH pulse pattern analysis. Therefore blood samples were drawn
every 10 min during a 24 h period. Sleep was recorded from midnight to 7
a.m. Repetition of the TRH tests at the end of the 24 h blood sampling
period confirmed the difference in stimulated TSH values of the two study
groups. Pulse analysis for luteinizing hormone (LH), TSH and prolactin
showed no differences between patients and controls for pulse frequency,
amplitude, height, length, area under curve (AUC) and the 24 h mean. Even
the hypothyroid patient had a normal LH pulse pattern. Additional
measurement of melatonin in pooled sera every 30 min gave the
well-documented diurnal profiles during day and night for both groups.
Patients had significantly higher melatonin values at seven time points
during the night. Peaks for LH, TSH, prolactin and cortisol were correlated
with the sleep stages wake, rapid eye movement, 1 + 2 and 3 + 4. We
concluded that corpus luteum insufficiency in female infertility cannot be
explained by subclinical hypothyroidism and thus should not be treated with
L-thyroxine for fertility reasons.
相似文献