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21.
J K Sakurada A Maury W M Tamashiro P M Araújo I J Camargo H A Rangel 《Research in immunology》1992,143(2):157-164
To verify whether anti-Trypanosoma-cruzi-proteinase antibodies are able to play a role in the development of Chagas' disease, CBA/J and C57BL/6 mice were immunized with purified proteinase fractions: antibody production was studied and passive immunization experiments were carried out. No significant differences were observed in the titre, isotype composition and specificity of the antibodies produced by the mouse strains. Immune sera produced in one strain was able to protect mice of both strains, provided that the challenge did not exceed the number of parasites corresponding to 30-fold the LD50. The data presented suggest that anti-proteinase antibodies may play a role in immunoprotection. 相似文献
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Magnetic resonance (MR) imaging has been used in the temporomandibular joint (TMJ) primarily to define the disk position. This report examines altered morphology and signal intensity characteristics of the TMJ disk as they relate to the severity of internal derangement. Two hundred sixteen joints in 133 patients with a history of such derangement. were imaged with MR. Disk position, signal intensity, morphology, and the presence of osteoarthritis were determined for each joint. The normal disk was not anteriorly displaced and had a normal "bow-tie" shape. A grade 1 disk was anteriorly displaced and had a normal shape; a grade 2 disk was anteriorly displaced and had an abnormal shape. Forty (19%) joints were considered normal; none of these exhibited osteoarthritis. One hundred thirty-nine (64%) joints were grade 1; osteoarthritis was found in 17%. Thirty-seven (17%) were grade 2; osteoarthritis was found in 95%. All forty normal joints had high or intermediate signal intensity in the disk. Osteoarthritic joints had a higher percentage of disks with diminished intensity (P less than .0001). Severe or untreated osteoarthritis is known to be a complication of TMJ internal derangements; hence this grading system seems to correlate with the severity of internal derangement. 相似文献
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A study of the degree of progesterone support required for the maintenance
of various stages of pregnancy was undertaken in mice. Mated females were
ovariectomized at various stages of pregnancy and progesterone and
oestradiol support provided by s.c. Silastic implants with known release
characteristics. In the earliest stages of pregnancy (days 1-5), very low
concentrations of progesterone (<25% of normal physiological values)
were sufficient to maintain pre-implantation stages and allow implantation.
In the immediate post-implantation period (days 5-9), the development of
implantation sites and decidualization required considerably higher
progesterone support. In mid-pregnancy (days 11-14), progesterone alone
could not maintain pregnancy unless present in very high amounts; however,
the presence of oestradiol during this period lowered the progesterone
requirements to well within the physiological range. This effect of
oestradiol started on day 11 but required the level of oestradiol support
to be kept within strictly defined limits, with high concentrations
inducing abortion. Progesterone alone was able to maintain pregnancy from
day 15. These results indicate that the minimal progesterone support
required for pregnancy in mice varies considerably at different stages of
pregnancy and is at least partly modulated by oestradiol.
相似文献
28.
Immunoglobulin M (IgM)-glycoinositolphospholipid enzyme-linked immunosorbent assay: an immunoenzymatic assay for discrimination between patients with acute toxoplasmosis and those with persistent parasite-specific IgM antibodies 总被引:2,自引:0,他引:2
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Giraldo M Portela RW Snege M Leser PG Camargo ME Mineo JR Gazzinelli RT 《Journal of clinical microbiology》2002,40(4):1400-1405
In the present study we developed an enzyme-linked immunosorbent assay (ELISA) to measure immunoglobulin M (IgM) specific for glycoinositolphospholipids (GIPL) derived from tachyzoite membrane (IgM-GIPL ELISA). The sensitivity and specificity of the assay were compared with those of commercially available Toxoplasma-specific IgM serological tests, namely, immunofluorescence assay (IFA) with fixed tachyzoites and capture ELISA employing tachyzoite extracts. Our results show that all patients with acute toxoplasmosis, as determined by clinical data and conventional serological tests, were also positive by the IgM-GIPL ELISA. Interestingly, many patients that were classified as indeterminate, who had IgG with high avidity but positive results in the IgM-specific IFA and capture ELISA, were negative by the IgM-GIPL ELISA. Finally, we tested the sera from patients with rheumatoid arthritis and various parasitic infections and found no evidence of false positives in the IgM-GIPL ELISA. 相似文献
29.
D S Colombari E Colombari W A Saad L A Camargo A Renzi L A De Luca Júnior J V Menani 《Neuroscience letters》1992,143(1-2):255-258
The present study was performed to investigate the effect of treatment with furosemide on the pressor response induced by intracerebroventricular (i.c.v.) injections of cholinergic (carbachol) and adrenergic (norepinephrine) agonists, angiotensin II (ANGII) and hypertonic saline (HS, 2 M NaCl). The changes induced by furosemide treatment on the pressor response to intravenous (i.v.) norepinephrine, ANGII and arginine vasopressin (AVP) were also studied. Rats with a stainless-steel cannula implanted into the lateral ventricle (LV) were used. Two injections of furosemide (30 mg/kg b.wt. each) were performed 12 and 1 h before the experiments. Treatment with furosemide reduced the pressor response induced by carbachol, norepinephrine and ANGII i.c.v., but no change was observed in the pressor response to i.c.v. 2 M NaCl. The pressor response to i.v. ANGII and norepinephrine, but not AVP, was also reduced after treatment with furosemide. These results show that the treatment with furosemide impairs the pressor responses induced by central or peripheral administration of adrenergic agonist or ANGII, as well as those induced by central cholinergic activation. The results suggest that the treatment with furosemide impairs central and peripheral pressor responses mediated by sympathetic activation and ANGII, but not those produced by AVP. 相似文献
30.
Expression in Escherichia coli of a dominant immunogen of Trypanosoma cruzi recognized by human chagasic sera.
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P C Cotrim G S Paranhos R A Mortara J Wanderley A Rassi M E Camargo J F da Silveira 《Journal of clinical microbiology》1990,28(3):519-524
A genomic clone expressing a Trypanosoma cruzi antigen in Escherichia coli was identified using human chagasic sera. Chagasic antibodies affinity purified on extracts of this clone recognized a high-molecular-weight protein expressed in all developmental stages of the parasite life cycle, as well as in various T. cruzi strains. The antigen is associated with the cytoskeleton of the parasite and localizes along the attachment region between the flagellum and the cell body. Antibodies to the recombinant antigen were detected in the sera of 115 chagasic patients from different endemic regions, but not in sera of patients with leishmaniasis, T. rangeli infection, or other parasitic diseases. Our data suggest that the presence of antibodies to this antigen may be specifically associated with Chagas' disease. 相似文献