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Cell-mediated immunity to proteoglycan antigens was assessed by leucocyte migration inhibition and by lymphocyte stimulation tests in patients with rheumatoid arthritis or with ankylosing spondylarthritis, in patients with relapsing synovitis after a single trauma to their knee joints, and in healthy donors. Both tests revealed a sensitization in most of the patients examined with various proteoglycan antigens derived from human cartilaginous tissues, rheumatoid synovial fluid, and species-common antigen of bovine nasal cartilage. Anybodies against proteoglycan antigens of human articular cartilage were detected by solid-phase radioimmunoassay in eleven out of twenty-nine sera from patients with rheumatoid arthritis and in four out of six rheumatoid synovial fluids. The results suggest that the cartilage antigenic components released by an inflammatory process or trauma may trigger a vicious circle of chronic inflammation and joint destruction. 相似文献
14.
G. SZÜCS M. KÁVAI P. SURÁNYI E. KISS I. CSIPÖ G. SZEGEDI 《Scandinavian journal of immunology》1994,40(5):481-484
The expression of FcγRI, FcγRII, and FcγRIII (the IgG receptors CD64, CD32, CD16) as well as CR3 (the C3bi receptor, CD11b) on monocytes in the blood of patients with systemic lupus erythematosus (SLE) was investigated. The relationship between the receptor expression and the serum immune complex (IC) concentration was analysed. The decrease in mean fluorescence intensity (FI) of the FcγRII of patients' monocytes stained by specific monoclonal antibodies (MoAb IV3) was very close to statistical significance ( P = 0.052). The expression (FI) of CR3 (using MoAb OKM1) on monocytes of patients was also decreased, but not significantly. The detected decrease of FcγRII and CR3 was inversely correlated with the high circulating immune complex level in patients' sera. At the same time, FcγRI expression on SLE monocytes (using MoAb 32) was significantly elevated and this change was in parallel with the serum IC concentration. 相似文献
15.
Rao VM; Dalinka MK; Mitchell DG; Spritzer CE; Kaplan F; August CS; Axel L; Kressel HY 《Radiology》1986,161(1):217-220
Four patients with proved osteopetrosis (three with the infantile malignant form and one with the benign form) were examined with magnetic resonance imaging at 1.5 T. All patients were studied in the coronal and sagittal planes using both short and long repetition time/echo time sequences. The infantile malignant form was characterized by a complete lack of signal from the marrow alternating with a signal intensity equivalent to that of the intervertebral disks, resulting in a "stepladder" appearance. In the benign form or after successful marrow transplantation in the infantile malignant form, intermediate or high signal intensity in the vertebrae was noted, suggesting the presence of some marrow elements. 相似文献
16.
Dimitrios Moris Brian I. Shaw Cecilia Ong Ashton Connor Mariya L. Samoylova Samuel J. Kesseli Nader Abraham Jared Gloria Robin Schmitz Zachary W. Fitch Bryan M. Clary Andrew S. Barbas 《肝胆外科与营养》2021,10(3):315
BackgroundSelection of the optimal treatment modality for primary liver cancers remains complex, balancing patient condition, liver function, and extent of disease. In individuals with preserved liver function, liver resection remains the primary approach for treatment with curative intent but may be associated with significant mortality. The purpose of this study was to establish a simple scoring system based on Model for End-stage Liver Disease (MELD) and extent of resection to guide risk assessment for liver resections.MethodsThe 2005–2015 NSQIP database was queried for patients undergoing liver resection for primary liver malignancy. We first developed a model that incorporated the extent of resection (1 point for major hepatectomy) and a MELD-Na score category of low (MELD-Na =6, 1 point), medium (MELD-Na =7–10, 2 points) or high (MELD-Na >10, 3 points) with a score range of 1–4, called the Hepatic Resection Risk Score (HeRS). We tested the predictive value of this model on the dataset using logistic regression. We next developed an optimal multivariable model using backwards sequential selection of variables under logistic regression. We performed K-fold cross validation on both models. Receiver operating characteristics were plotted and the optimal sensitivity and specificity for each model were calculated to obtain positive and negative predictive values.ResultsA total of 4,510 patients were included. HeRS was associated with increased odds of 30-day mortality [HeRS =2: OR =3.23 (1.16–8.99), P=0.025; HeRS =3: OR =6.54 (2.39–17.90), P<0.001; HeRS =4: OR =13.69 (4.90–38.22), P<0.001]. The AUC for this model was 0.66. The AUC for the optimal multivariable model was higher at 0.76. Under K-fold cross validation, the positive predictive value (PPV) and negative predictive value (NPV) of these two models were similar at PPV =6.4% and NPV =97.7% for the HeRS only model and PPV =8.4% and NPV =98.1% for the optimal multivariable model.ConclusionsThe HeRS offers a simple heuristic for estimating 30-day mortality after resection of primary liver malignancy. More complicated models offer better performance but at the expense of being more difficult to integrate into clinical practice. 相似文献
17.
Objective To detect new mutations among 29 glucose-6-phosphate dehydrogenase (G6PD) deficient individuals from Yunnan province. Methods The nitroblue tetrazolium (NBT) method was used to screen G6PD deficient individuals. Mutation was identified by single strand conformation polymorphism (SSCP), amplification created restriction site (ACRS), amplification refractory mutation system (ARMS) and DNA sequencing. Results Among 29 cases, 18 cases of G1388A, 1 case of C1004A, and 1 case of G1381A were identified. Nine cases remained to be defined. The G1381A mutation is a novel mis-sense mutation, with a substitution of threonine for alanine (A461T). The resultant G6PD had reduced enzymatic activity. In addition, G1381A caused a restriction site of Stu I to disappear, providing a rapid method for the detection of this mutation. Conclusion A novel mis-sense mutation G1381A was found. This mutation results in a substitution of threonine for alanine, producing enzyme with reduced activity. The loss of the Stu I restriction site offers a rapid method for the detection of this mutation. 相似文献
18.
Minority status within any larger group is often difficult. Lesbian nurses face a dilemma of choice—whether or not to come out of the closet to their colleagues and patients. This essay describes the professional reflections of one lesbian nurse. 相似文献
19.
Inhibition of growth and induction of apoptosis in human cancer cell lines by tea polyphenols 总被引:47,自引:7,他引:47
In order to study the biological activities of tea preparations and
purified tea polyphenols, their growth inhibitory effects were investigated
using four human cancer cell lines. Growth inhibition was measured by
[3H]thymidine incorporation after 48 h of treatment. The green tea
catechins (-)-epigallocatechin-3-gallate (EGCG) and (-)- epigallocatechin
(EGC) displayed strong growth inhibitory effects against lung tumor cell
lines H661 and H1299, with estimated IC50 values of 22 microM, but were
less effective against lung cancer cell line H441 and colon cancer cell
line HT-29 with IC50 values 2- to 3- fold higher.
(-)-Epicatechin-3-gallate, had lower activities, and (-)- epicatechin was
even less effective. Preparations of green tea polyphenols and theaflavins
had higher activities than extracts of green tea and decaffeinated green
tea. The results suggest that the growth inhibitory activity of tea
extracts is caused by the activities of different tea polyphenols. Exposure
of H661 cells to 30 microM EGCG, EGC or theaflavins for 24 h led to the
induction of apoptosis as determined by an annexin V apoptosis assay,
showing apoptosis indices of 23, 26 and 8%, respectively; with 100 microM
of these compounds, the apoptosis indices were 82, 76 and 78%,
respectively. Incubation of H661 cells with EGCG also induced a
dose-dependent formation of H2O2. Addition of H2O2 to H661 cells caused
apoptosis in a manner similar to that caused by EGCG. The EGCG-induced
apoptosis in H661 cells was completely inhibited by exogenously added
catalase (50 units/ml). These results suggest that tea polyphenol-induced
production of H2O2 may mediate apoptosis and that this may contribute to
the growth inhibitory activities of tea polyphenols in vitro.
相似文献
20.
Characterization of xenobiotic-metabolizing enzymes and nitrosamine metabolism in the human esophagus 总被引:5,自引:2,他引:5
Smith TJ; Liao A; Wang LD; Yang GY; Starcic S; Philbert MA; Yang CS 《Carcinogenesis》1998,19(4):667-672
Esophageal cancer has been associated with tobacco smoking, and
nitrosamines are possible causative agents for this cancer. The present
study investigated the metabolism of the tobacco carcinogens N'-
nitrosonornicotine (NNN), 4-(methylnitrosamino)-1-(3-pyridyl)-1- butanone
(NNK), and N-nitrosodimethylamine (NDMA), as well as the presence of
xenobiotic-metabolizing enzymes in human esophageal tissues from
individuals in the United States and Huixian, Henan Province, China (a
high-risk area for esophageal cancer). All esophageal microsomal samples
activated NNN and the metabolic rate was 2-fold higher in the esophageal
samples from China than the USA. All microsomal samples activated NDMA.
However, most of the microsomal samples did not activate NNK.
Troleandomycin (an inhibitor of cytochrome P450 3A) decreased the formation
of NNN-derived keto acid by 20-26% in the esophageal microsomes. The
activities for NADPH: cytochrome c reductase, ethoxycoumarin O-deethylase,
NAD(P)H: quinone oxidoreductase and glutathione S-transferase were present
in the esophageal samples. Coumarin 7-hydroxylase (a representative
activity for P450 2A6) activity was not detected in the esophageal
microsomal samples. The activities for nitrosamine metabolism and
xenobiotic- metabolizing enzymes were decreased (by 30-50%) in the squamous
cell carcinomas compared with their corresponding non-cancerous mucosa. The
presence of activation and detoxification enzymes in the esophagus may play
an important role in determining the susceptibility of the esophagus to the
carcinogenic effect of nitrosamines. Our results suggest that P450s 3A4 and
2E1 are involved in the activation of NNN and NDMA, respectively, in the
human esophagus.
相似文献