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1.
The abused child     
We compared the antigenic characteristics of two thermo-dependent dimorphic fungi isolated from soil in Botucatu, an endemic area of paracoccidioidomycosis (PCM) and Paracoccidioides brasiliensis. The soil isolates grew as cerebriform colonies at 37 degrees C (yeast form) and as cottonous colonies at 25 degrees C (mycelial form). No pathogenicity for ddY mice or hamsters were observed. In immunodiffusion test, there were precipitation bands between the 2 soil isolates and pooled PCM patient sera. There were also common precipitation bands at 21, 50 and 58 kDa between the soil isolates antigens and PCM patient sera by Western-blotting, but no gp43 kDa band. No gene for gp 43 kDa protein was detected in the soil isolates by PCR. The fact that these isolates were obtained from an endemic area of PCM and there were some antigenic similarities between the soil isolates and P. brasiliensis in immunodiffusion test and Western-blotting may have some importance in epidemiological surveys done with paracoccidioidin as well interfering with the immune response of the exposed population.  相似文献   

2.
To assess human cellular immune response to paracoccidioidomycosis (PCM), lymphocyte proliferative responses to purified antigens from Paracoccidioides brasiliensis were determined in healthy persons previously infected by the fungus (positive donors), in healthy noninfected persons (controls), and in PCM patients. Affinity-purified gp70 and gp43, the two major antigens in humoral immune responses, were used. Both induced lymphocyte proliferation (gp43 species-specific) in positive donors but not in controls; healthy persons previously infected by Histoplasma capsulatum reacted to gp70 and not to gp43. A similar cross-reactivity in antibody response to gp70 was previously reported; however, antibody response to gp43 has been considered specific. Lymphocytes from PCM patients, who, unlike positive donors, have high levels of anti-gp43 and anti-gp70 antibodies, proliferated poorly with gp70 and gp43 but better with other stimuli. This dichotomy between humoral and cellular antigen-specific responses suggests a Th2 immune response in PCM, which may be related to failure to control the infection.  相似文献   

3.
To examine the distribution of low molecular weight silicones in body organs, separate groups of female CD-1 mice were injected with either breast implant distillate composed primarily of hexamethylcyclotrisiloxane, octamethylcyclotetrasiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, and tetradecamethylcycloheptasiloxane or a polydimethylsiloxane oil containing low molecular weight linear siloxanes. Mice were injected subcutaneously in the suprascapular area and killed at different times. Levels of individual low molecular weight silicones were measured in 10 different organs (brain, heart, kidney, liver, lung, mesenteric lymph nodes, ovaries, spleen, skeletal muscle, and uterus). In mice treated with the cyclosiloxane mixture and killed at 3, 6, or 9 weeks, highest levels of cyclosiloxanes were found in the mesenteric lymph nodes, ovaries, and uterus, but all organs examined contained cyclosiloxanes. In a cohort killed at 1 year, most organs contained measurable cyclosiloxanes with highest levels in mesenteric lymph nodes, abdominal fat, and ovaries. Of the individual cyclosiloxanes measured, selective retention of decamethylcyclopentasiloxane and dodecamethylcyclohexasiloxane relative to octamethylcyclotetrasiloxane was seen in all organs at all time points studied. Organs from animals receiving the linear siloxane mixture were harvested at 9, 12, and 15 weeks. We found maximum levels in the brain, lungs, and mesenteric lymph nodes, but all other organs contained measurable levels. These data are, to the best of our knowledge, the first demonstration that after a single subcutaneous injection silicones are widely distributed throughout the body and can persist over an extended period.  相似文献   

4.
The number involved in and the rate of migration of donor leucocytes into the following recipient organs (spleen, thymus, bone marrow, lung and mesenteric lymph nodes) were measured in two rat models of orthotopic liver transplantation (OLT) using donor-specific MHC class I antibodies. The first OLT model is one that does not require immunosuppression in order to achieve tolerance and involved the transplantation of DA (MHC haplotype, RT1a) livers into PVG (RT1c) recipients. The second model was one that required a 7-day (10 mg/kg) treatment with cyclosporin A (CsA) to achieve tolerance and used DA donors into Lewis (RT1(1)) recipients. Recipient organs were biopsied on days 3, 20 and 87 following OLT and donor leucocyte migration was quantified by immunohistochemistry and computer densitometry of immunoblots of detergent-solublized tissues in order to resolve both membrane-bound and soluble donor MHC class I antigen. In a separate experiment, spleen biopsies were taken following OLT on days 3 and 15 from the naturally tolerizing OLT model (DA into PVG), treated with and without CsA for 7 days and compared with the (DA into Lewis) model. The initial rate of leucocyte migration between days 3 and 21 following OLT was found to be the most rapid into the spleen, followed by the bone marrow and mesenteric lymph nodes in the naturally tolerant (DA into PVG) model when compared with the (DA into Lewis) model. The number of donor leucocytes in the spleen and mesenteric lymph nodes in both models was, however, approximately the same by 87 days. No real difference in the rate of leucocyte migration was seen in the thymus or the lung for both transplant models over the time course assayed. CsA was found to lower the rate of donor leucocyte migration only over the period it was administered. The rate of donor leucocyte migration into the spleen was still much lower 15 days after OLT in the (DA into Lewis) model compared with the (DA into PVG) model treated with and without CsA. Thus the differences in the rate of donor leucocyte migration into the spleen, bone marrow and mesenteric lymph nodes immediately following OLT may offer an explanation as to why the (DA into PVG) combination is able to accept a transplanted liver without immunosuppressive therapy.  相似文献   

5.
For the diagnosis and follow-up of paracoccidioidomycosis patients undergoing therapy, we evaluated two methods (immunoblotting and competition enzyme immunoassay) for the detection of circulating antigen in urine samples. A complex pattern of reactivity was observed in the immunoblot test. Bands of 70 and 43 kDa were detected more often in urine samples from patients before treatment. The immunoblot method detected gp43 and gp70 separately or concurrently in 11 (91.7%) of 12 patients, whereas the competition enzyme immunoassay detected antigenuria in 9 (75%) of 12 patients. Both tests appeared to be highly specific (100%), considering that neither fraction detectable by immunoblotting was present in urine samples from the control group. gp43 remained present in the urine samples collected during the treatment period, with a significant decrease in reactivity in samples collected during clinical recovery and increased reactivity in samples collected during relapses. Reactivity of some bands was also detected in urine specimens from patients with "apparent cure." The detection of Paracoccidioides brasiliensis antigens in urine appears to be a promising method for diagnosing infection, for evaluating the efficacy of treatment, and for detecting relapse.  相似文献   

6.
We cloned and sequenced a species-specific 110-bp DNA fragment from Paracoccidioides brasiliensis. The DNA fragment was generated by PCR with primers complementary to the rat beta-actin gene under a low annealing temperature. Comparison of the nucleotide sequence, after excluding the primers, with those in the GenBank database identified approximately 60% homology with an exon of a major surface glycoprotein gene from Pneumocystis carinii and a fragment of unknown function in Saccharomyces cerevisiae chromosome VIII. By Southern hybridization analysis, the 32P-labelled fragment detected 1.0- and 1.9-kb restriction fragments within whole-cell genomic DNA of P. brasiliensis digested with HindIII and PstI, respectively, but failed to hybridize to genomic DNAs from Candida albicans, Blastomyces dermatitidis, Cryptococcus neoformans, Aspergillus fumigatus, Saccharomyces cerevisiae, Pneumocystis carinii, rat tissue, or humans under low-stringency hybridization conditions. Additionally, the specific DNA fragment from three different P. brasiliensis isolates (Pb18, RP18, RP17) was amplified by PCR with primers mostly complementary to nonactin sequences of the 110-bp DNA fragment. In contrast, there were no amplified products from other fungus genomic DNAs previously tested, including Histoplasma capsulatum. To date, this is the first species-specific DNA fragment cloned from P. brasiliensis which might be useful as a diagnostic marker for the identification and classification of different P. brasiliensis isolates.  相似文献   

7.
Paracoccidioidomycosis (PARA) affects only a minority of individuals, who have presumably been exposed to the causative fungus (Paracoccidioides brasiliensis). Neutrophils (PMNs) from patients with PARA show a significant and specific digestive deficiency phagocytosed P. brasiliensis in vitro. It is not known whether the defect is acquired after contact with the fungus, or precedes it. We studied the spouses and offspring of three patients with PARA. Individuals studied stayed in the same house as their husband or father. None of the relatives had evidence of PARA, and their PMNs showed no defect in their ability to digest or kill the fungus. Relatives showed no indication of sensitization against P. brasiliensis. These results are compatible with the view that effective contact with P. brasiliensis may occur only under restricted conditions and that the defect in digestive ability is an infrequent and specific occurrence.  相似文献   

8.
Twenty-seven mycologically proven cases of paracoccidioidomycosis (PCM) were treated with itraconazole (100-200 mg/day in month 1 and 100 mg/day until month 6-8) and evaluated clinically and serologically, up to 3.5 years post-therapy, using Dot-blot and ELISA for measuring the titers of IgG, IgA and IgM anti-P.brasiliensis antibodies and Western-blot for determining IgG, IgA and IgM antibodies against the antigen components of the fungus. Before treatment, 81.5% (Dot-blot) and 84% (ELISA) of the patients presented elevated IgG anti-P.brasiliensis antibody titers which dropped slightly with treatment. On the other hand, the percentages of pre-treatment high-titered sera for IgA and IgM anti-P.brasiliensis were lower (51.9% and 51.8%: Dot-blot; 16.5 and 36%: ELISA, respectively) but the titers tended to become negative more frequently with treatment. Prior to treatment, the percentages of positivity for IgG, IgA and IgM anti-P.brasiliensis antibodies in Western-blot were 96%, 20.8% and 41.6%, respectively. Antigens with molecular weights varying from 16-78 kDa, from 21-76 kDa and from 27-78 kDa were reactive for IgG, IgA and IgM antibodies, respectively. The most frequently reactive antigenic components had molecular weights of 27, 33 and 43 kDa for IgG, and 70 for IgA and IgM antibodies. During the period of study, the patients responded well to treatment. The present data confirm the diversity and complexity of the humoral response in PCM, and the importance of utilizing different serological tests to detect IgG, IgA and IgM anti-P. brasiliensis antibodies.  相似文献   

9.
The membrane expression of low-affinity Fc receptors for IgG (Fc gamma RII/III) on cells and the number of Fc gamma RII/III(+) cells were studied by flow cytometry, using the 2.4G2 MoAb, in mice infected by Trypanosoma cruzi. Cells from spleen, mesenteric lymph nodes and peritoneum were collected on days 10, 20, 30 and 40 post infection (p.i.). The in vivo serum level of soluble Fc gamma RII/III, as well as its in vitro release by cells from infected mice were studied. Parasitaemia and IgG1, IgG2a and IgG2b T. cruzi-specific antibody titres were also recorded. Both the expression of Fc gamma R on cell membrane and the absolute number of Fc gamma R(+) cells increased in spleen and in mesenteric lymph nodes, but not in peritoneum. The modifications in spleen occurred in the early and late parasitaemic phase of infection, i.e., before and after detection of T. cruzi-specific antibodies (from day 10 to 40 p.i.). In mesenteric lymph nodes, the variations were observed only in the early acute infection, when antibodies were not yet detectable at significant levels (on days 10 and 20 p.i.). Higher levels of soluble Fc gamma R were detected in sera and in culture supernatants of spleen and lymph node cells from day 20 to 40 p.i. These results show that T. cruzi infection in mice upregulates the expression and the release of Fc gamma RII/III, in the acute phase of infection, before as well as after the rise of antibody response.  相似文献   

10.
Although extensive research has been carried out on the respiratory and renal effects of intra-abdominal pressure increase, there is limited research with regard to its effects on bacterial translocation. The objective of this study was to discuss whether the high intra-abdominal pressure due to carbon dioxide (CO2) insufflation during laparoscopy leads to bacterial translocation. Eighteen male dogs, 7 of which constituted the control group, were used in the study. Two study groups, in which the intra-abdominal pressure was raised to 15 mm Hg and kept at that level for 30 and 120 minutes, respectively, were set. Blood gases and blood pressure values were observed throughout the experiments. Samples of peritoneal smear, portal vein blood, mesenteric lymph node, liver, spleen, and cecum were examined to detect bacterial translocation. Histopathological examinations of all samples were also carried out. No translocation was detected in the samples of peritoneal smear, portal blood, mesenteric lymph node, liver, or spleen, but in the samples of cecum, bacterial colonization for the second group (p<0.05) and for the third group (p<0.05) was significantly higher compared with the control group. There was a considerable difference between the second and third groups (p<0.05). The changes in the mesenteric lymph nodes were interpreted to be a result of bacterial drainage. Histopathological examination disclosed active changes in the mesenteric lymph nodes in all groups, but there was considerable sinus histiocytosis only in the third group. We conclude that the intraabdominal pressure of 15 mm Hg created by carbon dioxide insufflation does not lead to bacterial translocation but causes intraluminal bacterial colonization in the cecum after 30 minutes and after 2 hours.  相似文献   

11.
PURPOSE: To clarify the contrast enhanced CT features and anatomic distribution of the disseminated vs non-disseminated tuberculosis (TB) involving abdominal lymph nodes. MATERIALS AND METHODS: The contrast enhanced CT findings of abdominal lymphadenopathy in 25 patients, including disseminated TB associated with miliary TB of the lung (n = 5) and non-disseminated TB (n = 20), were retrospectively evaluated in a blind review to assess our criteria of morphology, density and location of the involved lymphadenopathy. RESULTS: The enhancement patterns of disseminated TB were not different from those of non-disseminated TB. Ninety-six percent of the patients had peripheral rim enhancement, and 60% showed a multilocular appearance. The enlarged lymph nodes of TB were less than 4 cm in diameter. Lymphadenopathy caused by hematogenous dissemination often accompanied splenic involvement showing multiple low-density foci in the spleen. The predominant sites of lymphadenopathy of disseminated TB were hepatoduodenal ligamentous, hepatogastric ligamentous, mesenteric, and both upper and lower portions of the retroperitoneal lymph nodes, whereas non-disseminated TB mainly involved hepatoduodenal ligamentous, hepatogastric ligamentous, mesenteric and upper retroperitoneal lymph nodes, excluding the lower retroperitoneal lymph nodes. By combining contrast enhancement patterns and the anatomic distribution of lymphadenopathy shown on the contrast enhanced CT images, reviewers made a correct diagnoses of tuberculosis in 94%, of cases, with a specificity of 95% and sensitivity of 92%. CONCLUSION: Contrast enhanced CT patterns correlate well with the pathologic features of tuberculous lymphadenopathy. A different anatomic distribution between disseminated and non-disseminated TB involving the lower retropentoneal lymph nodes was recognized in this study.  相似文献   

12.
One male of a group of seven Pacific white-sided dolphins (Lagenorhynchus obliquidens) died after a brief period of nonspecific clinical signs. Four beluga whales (Delphinapterus leucas) and four harbor seals (Phoca vitulina) were managed in the same water system. Gross examination of the dolphin revealed only moderately enlarged mesenteric lymph nodes. Histopathology revealed small to massive numbers of gram-positive bacilli, usually intravascular, in all tissues. Bacteria were both extracellular and present in macrophages, monocytes, and neutrophils. Aerobic bacterial culture of lung, liver, kidney, and spleen yielded pure cultures of Erysipelothrix rhusiopathiae. Based on clinical course, histopathology, and bacteriology, a diagnosis of acute erysipelas septicemia was made. None of the other cetaceans or pinnipeds exhibited clinical signs.  相似文献   

13.
Subchronic 90-day feeding studies were conducted on four highly refined white mineral oils to determine any potential for toxicity in Long-Evans rats (20 per sex per dose level) and beagle dogs (4 per sex per dose level). Each oil was fed at dietary dose levels of 300 ppm and 1500 ppm (w/w). No treatment-related effects of toxicological importance were detected in daily observations of general health or in periodic assessments of food consumption and body weight, hematology, serum clinical chemistry, and urinalysis. Observations in dogs suggested that the white oils produced mild laxative effects. Gross and histopathologic examinations, as well as measurements of organ weights, did not reveal any macroscopic or microscopic changes which could be due to treatment. In addition, special staining by Oil Red O of liver, mesenteric lymph nodes, spleen, gastrointestinal tract, stomach, and kidneys indicated no evidence of oil or lipid deposition. A special re-examination of tissues from female and male rats, in response to more recent conflicting data from the Fischer 344 strain, found no histopathologic signs of macrophage accumulation and/or microgranuloma formation in liver, spleen, or mesenteric lymph nodes. These data indicate that repeated exposure to relatively high levels of white mineral oils in the diets does not produce significant subchronic toxicity in Long-Evans rats or beagle dogs.  相似文献   

14.
The primary structures of the interferon-gamma-inducible mouse 20S proteasome subunit MECL-1 and its alternate homolog MC14 were determined. Northern analysis of mouse tissues revealed that MECL-1 mRNA predominantly occurred in thymus, lymph nodes, and spleen, whereas small amounts were detected in non-lymphoid tissues such as kidney, muscle, and testis. Unexpectedly, probing RNA blots with MC14 showed that tissues with high MECL-1 expression contained little MC14 and vice versa. A very similar reciprocal tissue expression was subsequently found for the homologous subunit pairs LMP2 and delta as well as LMP7 and MB1. The subunit protein composition of 20S proteasomes purified from liver, thymus, and lung reflected RNA expression. The impact of a regulated reciprocal tissue expression is discussed with respect to thymic selection and the induction of tolerance in potentially autoreactive T cells.  相似文献   

15.
Campylobacter jejuni infection of mice initiated by intranasal administration was investigated as a potential model for studies of pathogenesis and immunity. By using a standard challenge (5 x 10(9) CFU), C. jejuni 81-176 was more virulent for BALB/c (72% mortality) than for C3H/Hej (50%), CBA/CAJ (30%), or C58/J (0%). Intranasal challenge of BALB/c was used to compare the relative virulence of three reference strains; C.jejuni 81-176 was more virulent (killing 83% of challenged mice) than C. jejuni HC (0%) or C. coli VC-167 (0%). The course of intranasally initiated C. jejuni 81-176 infection in BALB/c was determined. C. jejuni was recovered from the lungs, intestinal tract, liver, and spleen at 4 h after challenge, the first interval evaluated. After this initial interval, three distinct patterns of infection were recognized: (i) a progressive decline in number of C. jejuni CFU (stomach, blood, lungs), (ii) decline followed by a second peak in the number of organisms recovered at 2 or 3 days postchallenge (intestine, liver, mesenteric lymph nodes), and (iii) persistence of approximately the same number of C.jejuni CFU during the course of the experiment (spleen). Intranasally induced infection initiated with a sublethal number of bacteria or intranasal immunization with killed Campylobacter preparations resulted in both the generation of Campylobacter antigen-specific immune responses and an acquired resistance to homologous rechallenge. The model was used to evaluate the relative virulence of nine low-in vitro-passage (no more than five passages) isolates of C. jejuni species from patients with diarrhea. The patient isolates were differentially virulent for mice; one killed all exposed mice, three were avirulent (no deaths) and the remainder showed an intermediate virulence, killing 17 to 33%. Mouse virulence of Campylobacter strains showed a trend toward isolates originating from individuals with watery diarrhea; however, no association was found between mouse virulence and other signs or symptoms. There were no observed relationships between mouse virulence and bacterial Lior serotype or Fla polymorphic group. Intranasal challenge of BALB/c with C. jejuni is a useful model for the study of infection and vaccination-acquired immunity to this agent.  相似文献   

16.
Fresh and cryopreserved autologous or allogeneic mononuclear blood cells (MBCs) intravenously injected in 1200 R total-body x-irradiated dogs repopulated lymph nodes within 10 days after tranfusion. Several parameters of the lymphopoietic regeneration were correlated with the number of cells transfused and with the number of colony-forming units contained in the cell suspension when they were cultured in agar (CFUc). Values within the normal or close to normal range were reached in the mesenteric nodes of most of the animals transfused with 10 X 10(9) MBC or more. These values were obtained when 5 X 10(5) CFUc or more were transfused. Axillary nodes showed lower values than mesenteric nodes. They were mostly under the normal range but well over those of the irradiated controls. Frozen and thawed MBCs seem to be as effective as fresh cells for lymphopoietic restoration. The mesenteric nodes of dogs transfused with allogeneic MBCs showed higher cellularity and larger cortical-paracortical areas than those of dogs tranfused with approximately the same number of autologous cells. The repopulation of lymph nodes parallels that of the marrow.  相似文献   

17.
Histochemical studies were performed on tissues from piglets of different ages treated orally with iron dextran soon after birth. The mucosal cells in the distal region of the small intestine were heavily laden with stainable iron granules during the first three days after the iron administration. The absorptive epithelial cells are desquamated within seven to ten days after birth. Consequently, the number of iron granules gradually diminishes during the first seven days after treatment and no iron granules are demonstrated 12 days after the administration of iron. The iron dextran complex is pinocytosed in newborn piglets and then transported via the lymphatic system. Thus the sinusoidal lining cells of the body and mesenteric lymph nodes are already heavily laden with iron granules 24 hours after oral treatment. This iron store is released only slowing during the first weeks of life. Great amounts of iron granules are demonstrated in the liver and spleen macrophages during the first week after the administration of iron. Due to the rapid utilization of iron in growing piglets these iron stores diminish sharply during the weeks following birth. The distribution of stainable iron in the lymph nodes, liver and spleen seven days after intramuscular injection of iron dextran in newborn piglets was comparable to that for oral administration at that stage of the experiment.  相似文献   

18.
The necropsy records of 78 patients with histologically proved germ cell tumors of the testis, who died as a direct result of their malignant disease, were reviewed to determine the usual modes of spread, distribution of metastasis, the histologic characteristics of the metastatic foci as compared with the morphology of the primary tumor and the specific cause of death. The sites of metastases in order of decreasing frequency for all cases were lung, retroperitoneal lymph nodes, liver, mediastinal lymph nodes, brain, kidney, gastrointestinal tract, bones, adrenals, peritoneum and spleen. The absence of metastases solely in the anterior mediastinum without involvement of other mediastinal nodes (middle/posterior) strongly supports the premise for a primary extragonadal origin whenever the anterior mediastinum alone is involved with malignant disease having the histologic appearance of a primary germ cell tumor. The histologic features of the metastatic lesions were usually similar in nature to those of the primary tumor except for seminoma in which the metastatic lesions proved to be of a different histologic pattern in almost one third of the patients dying from the disease. It should be axiomatic that whenever a patient with seminoma fails to respond appropriately to radiotherapy that his treatment be immediately discontinued and that appropriate biopsies be obtained to substantiate the histologic pattern present.  相似文献   

19.
The morphology of lymph node tissue from normal hamsters and from hamsters experimentally infected with Treponema pertenue Gauthier was compared by means of light and electron microscopy. The capsules of the lymph nodes from infected hamsters showed an increased thickness in comparison with those of the non-infected animals. The infected lymph nodes differed from normal lymph nodes by small accumulations of neutrophilic leucocytes in the cortical areas. In addition, the amount of intercellular collagenous matrix present between large elongated cells was greatly increased in lymph nodes from infected animals. Electron microscopy of thin sections of infected lymph nodes showed intercellularly located treponemes in the leucocyte infiltration areas. These regions also showed the increased amounts of the collagenous matrix. Treponemes were occasionally found intracellularly in macrophages. These treponemes did not show their typically helical shape, but were present as spherical forms or cysts.  相似文献   

20.
A specific antigen of Paracoccidioides brasiliensis was isolated from a metabolic extract of the fungus. The extraction was made by specific adsorption to and subsequent elution from a column containing a cross linked polymer to which the antibodies of a monospecific rabbit serum had been covalently attached. The purity of the final product was demonstrated by immunodiffusion analysis of the eluate using immune serum produced in a sensitized rabbit. The purified antigen was shown to have cationic electrophoretic mobility and alkaline phosphatase activity.  相似文献   

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