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Biomedical subjects

I Rantala

Publications and source records attributed to I Rantala.

At least 55 records · Page 3Linked to original sources
PubMed1993

Lactobacillus casei strain GG reverses increased intestinal permeability induced by cow milk in suckling rats.

BACKGROUND: Lactobacilli constitute a major part of the microflora throughout the gastrointestinal tract. This study aimed to investigate the effect of lactobacilli on the gut mucosal barrier. METHODS: Rat pups were divided into three experimental feeding groups at the age of 14 days. In addition to normal maternal milk, group "milk" received a daily gavage of cow milk, group "milk-GG" received Lactobacillus casei strain GG with cow milk, and controls were gavaged with the same volume of water. At 21 days, the absorption of horseradish peroxidase across patch-free jejunal segments and segments containing Peyer's patches was studied in Ussing chambers. RESULTS: The mean absorption of intact horseradish peroxidase expressed in ng.h-1.cm-2, was significantly different in the study groups in both patch-free segments (controls, 9 [95% confidence interval, 7-12]; milk, 72 [60-87]; and milk-GG, 15 [4-52]) and in segments containing Peyer's patches (controls, 3 [1-17]; milk, 80 [43-151]; and milk-GG, 15 [4-56]). There was a significant increase in the frequency of cells secreting antibodies to beta-lactoglobulin (enzyme-linked immunospot assay) in the milk-GG group. CONCLUSIONS: Prolonged cow milk challenge in suckling rats increases gut permeability to intact proteins, whereas Lactobacillus GG counteracts this permeability disorder. The results suggest a link between the intensity of the antigen-specific immune response and stabilization of the mucosal barrier.

Animals↗
PubMed1993

Increased in vitro intestinal permeability in suckling rats exposed to cow milk during lactation.

Specific mucosal barrier functions of the gut develop in the newborn to combat the constant challenge of foreign antigens. To determine whether exposure to cow milk antigens interferes with this maturational process, jejunal permeability to macromolecules and the activation of immune mechanisms were studied in preweaning rats. At the age of 14 days, rat pups were divided into three feeding groups. Controls (n = 18) remained on normal maternal milk; group CM (n = 27) additionally received a daily gavage feed of cow milk; and in group D (n = 23), cow milk was given to dams. At 21 days, when "gut closure" normally occurs, intestinal in vitro absorption of horseradish peroxidase in its intact form was significantly higher in group CM and in group D than in controls (F = 5.6; p = 0.006): group CM: mean, 37.8 ng/h/cm2; 95% confidence interval (CI), 19.4-73.6; group D: mean, 26.9 ng/h/cm2; 95% CI, 8.2-88.2; controls: mean, 4.0 ng/h/cm2; 95% CI, 1.2-13.9. In association with increased jejunal permeability, there was enhanced jejunal eosinophilic infiltration in group CM. In group D, the number of specific antibody-secreting cells in peripheral blood against beta-lactoglobulin was significantly higher than in group CM and controls. These data indicate that there is a critical period in development when feeding cow milk antigens delays gut closure. They further suggest that mucosal barrier function is impaired due to a local hypersensitivity reaction to cow milk antigens, irrespective of the protection of maternal milk or maternal antigen processing.

Age Factors↗
PubMed1993

Depletion of Langerhans cells in cervical HPV infection is associated with replication of the virus.

We studied the quantity of Langerhans cells in 36 patients with cervical human papillomavirus (HPV) infection. Significantly fewer Langerhans cells (p < 0.05) were found in patients with compared to those without DNA tetraploidy. Similarly, patients positive for HPV 16/18 DNA by in situ hybridization or antipeptide IgA antibodies to HPV 18 tended to have fewer Langerhans cells than those negative for HPV 16/18 DNA or IgA antibodies. Our results suggest that depletion of Langerhans cells is associated with productive HPV 16/18 infection in the cervical epithelium.

Antibodies, Viral↗
PubMed1993

Immunoglobulin and complement deposition in glomeruli of 756 subjects who had committed suicide or met with a violent death.

AIMS: To study immune deposits in renal glomeruli. METHODS: Tissue was obtained from 756 necropsy cases from people who had committed suicide or met with a violent death. Glomerular immune deposits were examined by immunofluorescence microscopy and a light microscopy. The clinical histories of all the decreased were studied to ascertain reasons for the deposits. RESULTS: Immune deposits were found in glomeruli in 91 (12%) cases. In 52 (6.8%) cases mesangial IgA was observed as a solitary finding in 34 (4.5%), and was accompanied by other immunoglobulins in 18 (2.4%). Mesangial IgM was present in 19 (2.5%) and IgG in 11 cases (1.5%). Two cases had capillary IgG (0.3%). Light microscopic examination showed mesangial enlargement in eight of the cases with mesangial IgA. These included one with IgA glomerulonephritis diagnosed before death. Two cases with normal glomerular morphology and mesangial IgA deposits had clinical laboratory evidence of renal disease. In two subjects with normal glomerular morphology, mesangial IgM and microscopic haematuria were present. In one case with capillary IgG membranous glomerulonephritis was detected. CONCLUSIONS: Ten cases had mesangial IgA together with morphological or clinical laboratory findings suggestive of renal disease. If all these are regarded as IgA glomerulonephritis, then its prevalence can be estimated at 1.3%. For IgM glomerulonephritis, a prevalence of 0.3% was deduced.

Adolescent↗
PubMed1993

Diet during rotavirus enteritis affects jejunal permeability to macromolecules in suckling rats.

We studied the influence of diet during diarrhea on gut mucosal barrier in a suckling rat model. Rat pups were inoculated with IDIR virus (a group B rotavirus) at 10 d of age. Beginning 2 d postinfection, in addition to maternal milk, group CM received a daily gavage of cow milk and group GG received Lactobacillus casei strain GG, a human strain previously shown to survive the passage through the gastrointestinal tract and temporarily colonize the gut. Group CMGG received a combination of these, and control animals were gavaged with tap water. At 21 d of age, jejunal absorption of intact and degraded horseradish peroxidase (HRP) in Ussing chamber was markedly higher in IDIR virus-infected than in noninfected controls. In the two groups gavaged with cow milk, group CM and group CMGG, the numbers of specific antibody-secreting cells (enumerated by the solid-phase enzyme-linked immunospot assay) against beta-lactoglobulin were significantly higher than in the groups that had not received cow milk. In parallel with immune system activation, a statistically significant increase in the absorption of intact HRP (mean and 95% confidence interval, ng x h-1 x cm-2) was detected: group CM, 302 (155, 586); group CMGG, 174 (56, 545); infected controls, 121 (57, 257); and group GG, 44 (8, 254). A decrease in the uptake of intact HRP (F = 3.64, p = 0.06) and degraded HRP (F = 9.50, p = 0.004) was associated with the introduction of L. casei GG to the diet, irrespective of coexposure to cow milk.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Aberrant p53 expression in astrocytic neoplasms of the brain: association with proliferation.

Aberrant expression of the p53 suppressor gene was evaluated in 102 cases of astrocytic neoplasms. Immunohistochemical staining with a monoclonal antibody (DO-7) and a polyclonal antibody (CM-1) to p53 protein (both wild type and mutant) on formalin-fixed paraffin sections showed a strong correlation with malignancy grade. The staining was positive in 49% of malignant neoplasms (grades III and IV) and in 19 to 29% of grade II astrocytomas, whereas none of the grade I tumors were positive. p53 expression was significantly associated with proliferation rate determined by immunohistochemical proliferating cell nuclear antigen (PCNA)-staining (median PCNA-labeling index (%): 4.22 (DO-7-positive) versus 1.18 (DO-7-negative), P < 0.0001; 4.02 (CM-1-positive) versus 1.18 (CM-1-negative), P < 0.001). Interestingly, in the glioblastoma group (n = 44), p53-positive tumors had higher proliferation indices, suggesting that histologically similar tumors could be divided into prognostically different subgroups by immunohistochemical demonstration of aberrant p53 expression.

Analysis of Variance↗
PubMed1992

Evidence for a structural abnormality of collagen VII in a patient with dystrophic epidermolysis bullosa inversa.

Recent studies indicate that in skin of patients with dystrophic epidermolysis bullosa (EB) inversa, anchoring fibrils have an abnormal ultrastructure, but the major protein of these fibrils, collagen VII, is expressed and detectable with antibodies at the dermo-epidermal junction. For molecular characterization of this rare EB phenotype, skin biopsies from a patient with dystrophic EB inversa were investigated with indirect immunofluorescence, immunoelectron microscopy, and immunoblotting. Ultrastructural analysis of clinically uninvolved skin showed sublamina densa splitting. In unblistered areas, focal groups of anchoring fibrils that appeared loosely polymerized and without a distinct crossbanding pattern were observed. Indirect immunofluorescence staining with antibodies to collagen VII exhibited a linear fluorescence at the dermo-epidermal junction and at the roof of a spontaneous blister. Immunoelectron microscopy demonstrated staining of the poorly assembled anchoring fibrils, but no significant reaction in areas where no fibrillar structures could be discerned. In contrast to normal control skin, immunoblotting showed immunoreactive collagen VII in both epidermal and dermal extracts. Moreover, the dermis-associated collagen VII appeared as a distinct doubleband that contained the tissue form of collagen VII (250-300 kD) and an additional band with a slightly smaller molecular weight. In epidermal extracts one band, of the size of the tissue form, was detected. The studies on the present patient suggest that a structural abnormality of collagen VII that prevents its aggregation to stable dimers or polymerization to distinct anchoring fibrils may contribute to the etiopathogenesis of dystrophic EB inversa.

Adult↗
PubMed1992

Proliferative activity of human uterine leiomyoma cells as measured by automatic image analysis.

Proliferative activity of uterine leiomyomas from premenopausal (n = 44) and postmenopausal (n = 12) women was investigated by automatic image analysis on frozen tissue sections using immunohistochemistry with anti-proliferating cell nuclear antigen antibody. The quantitative proliferation index (QPI) in premenopausal leiomyoma cells was significantly (p < 0.025) higher than that in leiomyomas in postmenopausal women. Leiomyomas proliferated most actively during the secretory phase. After the climacterium, leiomyomas showed no proliferative activity in the absence of hormone supply, while combined substitution with estrogen and progestagen considerably increased QPI.

Antibodies, Anti-Idiotypic↗
PubMed1992

Early dietary antigens delay the development of gut mucosal barrier in preweaning rats.

To determine the effects of early antigen exposure on the maturation of the gastrointestinal mucosal barrier, rat pups were divided into three groups at the age of 14 d. In addition to normal maternal milk, group CM (n = 24) received daily a gavage feed of cow's milk and group PH (n = 20) a whey protein hydrolysate during the experimental feeding period (14-20 d). Controls (n = 15) remained on maternal milk only. At 21 d, when "gut closure" normally occurs, intestinal absorption of horseradish peroxidase (HRP), was examined in vitro in Ussing chambers. The absorption of intact HRP [geometric mean (95% confidence interval)] was significantly higher in group CM [35.3 (16.7, 74.7) ng.h-1.cm-2] than in group PH [5.2 (1.4, 19.5) ng.h-1.cm-2] and in controls [3.4 (0.8, 15.1) ng.h-1.cm-2; F = 5.54, p = 0.006]. The absorption of degraded HRP was comparable in all groups. There were no modifications in electrical parameters in association with increased mucosal permeability to HRP. Furthermore, in group CM electron-microscopic studies disclosed accumulation of HRP in the cytoplasm of the epithelial cells and in the intercellular spaces where cell junctions remained unaltered. These results indicate that early administration of antigens delays the process of gut closure. They further suggest that continuously enhanced endocytosis of macro-molecules is induced by an insult to the mucosa as part of the host response to these antigens, irrespective of the protection afforded by maternal milk.

Animals↗
PubMed1991

Human papillomavirus types 16 and 18 in adenocarcinoma of the uterine cervix.

Many reports have shown a link between human papillomavirus (HPV) and cervical squamous neoplasia. However, the association of HPV with cervical adenocarcinoma has been studied less extensively. The authors evaluated the presence of HPV-DNA in 106 patients with adenocarcinoma of the uterine cervix by in situ hybridization, using 35S-labeled probes for HPV 16 DNA and HPV 18 DNA. The overall prevalence of HPV-DNA was 18% (19 of 106). HPV 16 was present in 2 (2%) cases, HPV 18 was observed in 15 (14%) cases, and both HPV 16 and HPV 18 were found in 2 (2%) cases. There was a correlation between HPV-DNA positivity and tumor stage (P less than 0.01) and tumor size (P less than 0.05), but there was no relationship between HPV-DNA positivity and tumor differentiation, proliferation (S-phase fraction), ploidy, lymph node metastases, or five-year survival rate. These results suggest that HPV 18 DNA is associated with cervical adenocarcinoma but the presence of HPV 18 has no influence on overall survival.

Adenocarcinoma↗
PubMed1991

Gastric parietal, chief, and G-cell densities in chronic renal failure.

We calculated morphometrically the amount of antral gastrin-producing (G) cells and body parietal and chief cells in gastric biopsy specimens from 30 undialysed patients with chronic renal failure (CRF) and from sex- and age-matched controls. The CRF patients had raised fasting serum gastrin levels, whereas these were normal in the controls (mean, 290 +/- 283 (+/- SD) ng/l (n = 27) versus 33 +/- 36 (n = 30)). Serum gastrin values of the patients and controls correlated positively with G-cell density (r = 0.501, n = 36, p = 0.002), as did the maximal acid output of the CRF patients with parietal cell density (r = 0.617, n = 14, p = 0.019). In CRF patients the densities of G, parietal, and chief cells were higher than those in the controls (G cells, 351 +/- 151 (+/- SD) cells/mm2, n = 21 versus 211 +/- 90, n = 16, p = 0.002; parietal cells, 299 +/- 94, n = 15 versus 224 +/- 72, n = 14, p = 0.025; chief cells, 886 +/- 346, n = 15 versus 743 +/- 182, n = 14, p = 0.181). The results agree with previous findings indicating that hyposecretion of gastric acid in CRF does not derive from decreased capacity for acid secretion but rather from the inhibition of acid output. Increased parietal cell density in CRF patients gives cause to suspect that the maximum acid output might even in raised, possibly depending on the permanent hypergastrinaemic state with its trophic influence on the gastric body mucosa.

Adult↗
PubMed1991

In vivo attachment of group A streptococci to tonsillar epithelium during acute tonsillitis.

The attachment of group A beta-hemolytic streptococci (GABHS) to the tonsillar epithelium during current acute tonsillitis (AT) was studied by means of fluorescence microscopy and electron microscopy in 5 patients. Conventional cultures from the tonsils showed massive growth of GABHS and tonsillar epithelial cells were heavily infested with GABHS, which proved positive for FITC-labelled antibodies against beta-hemolytic streptococci. The bacteria were firmly attached to the epithelial cell membranes by cell projections, which grasped the microorganisms from various directions. A 24 h course of oral treatment with phenoxymethylpenicillin radically affected bacterial adherence to the epithelial cells.

Acute Disease↗
PubMed1990

Glomerular IgA deposits in patients with celiac disease.

Glomerular immunopathology was studied in 25 patients with newly diagnosed celiac disease. None had clinical signs of renal disease. Glomeruli were obtained by fine-needle aspiration biopsy. The specimens were processed and studied by indirect immunofluorescence for immunoglobulins and complement. Mesangial IgA was found in 8 of the patients. It occurred occasionally together with slight IgG or IgM, but C3 was not seen in these patients. IgA-class circulating immune complexes (CIC), antireticulin antibodies (ARA), antigliadin antibodies (AGA), and rheumatoid factor (RF) occurred significantly more often in the patients with mesangial IgA than in the 17 patients having no mesangial IgA. The patients with mesangial IgA also had significantly higher mean levels of serum IgA, IgA-ARA and IgA-AGA than those without. The results suggest that glomerular mesangial deposits of IgA occur frequently in untreated celiac disease and that they are in some way associated with circulating IgA-class antibodies and immune complexes. In this situation IgA seems to be deposited without being able to induce clinically overt glomerulonephritis, a circumstance that may be related to the lack of complement in the deposits.

Adolescent↗
PubMed1989

The relation between serum sex steroid levels and plasma cell infiltrates in endometritis.

We measured serum levels of progesterone and estradiol among 35 patients with endometritis confirmed by endometrial biopsy. The onset of symptoms took place predominantly in the proliferative phase of the cycle. A negative correlation was found between the serum progesterone levels and the histopathologic severity of plasma cell endometritis. Our results suggest that the hormonal status contributes to the immune response and susceptibility to endometrial infection.

Cell Count↗
PubMed1989

Immediate decrease in antigen-presenting function and delayed enhancement of interleukin-1 production in human epidermal cells after in vivo UVB irradiation.

Human skin was irradiated in vivo with a single UVB dose (100 mJ/cm2 or 200 mJ/cm2) to examine simultaneously the antigen-presenting function and interleukin-1 (IL-1) production capacity of irradiated epidermal cells (EC). Suction blisters were produced on irradiated areas on days 0, 3 and 7 after UVB. Irradiated EC were harvested and co-cultured with autologous T lymphocytes in the presence of antigens (PPD, HSV) or mitogen (ConA). Culture supernatants were tested for IL-1 activity using the thymocyte comitogenity assay. We found that a single 200 mJ/cm2 dose of UVB caused an immediate suppression of the antigen-presenting function of EC, but no alteration in their IL-1 production capacity or surface marker expression (ATPase, CDI). PPD- and HSV-induced lymphocyte proliferation was decreased 70-80% and ConA-driven proliferation 30% when compared to non-irradiated EC. However, this suppression was restored on days 3 and 7 after UVB irradiation, this being coexistent with an increased capacity of EC to produce IL-1. It remains to be elucidated whether the immediate UVB-induced photoimmunosuppression observed in the present study is due to inhibitory mediators or impaired membrane function of EC or both.

Adult↗
PubMed1989

Immunofluorescence of immunoglobulins and complement in kidneys taken at necropsy.

The immunofluorescence of immunoglobulins and complement components in kidney specimens taken at necropsy was investigated to determine the persistence of antigenicity of immune reactants. Of 74 consecutive necropsies, 12 cases had positive glomerular fluorescence. The pattern and intensity were followed up for up to 15 days. Along with necropsy specimens, tissue samples of normal looking kidney from 14 nephrectomies were also studied. Two of these specimens turned out to be positive in the immediate immunofluorescence study. To rule out possible false positive staining after death immunofluorescence findings in all nephrectomy specimens were followed up for up to 19 days. The presence of immunoglobulins and complement could be shown for between 12 and 15 days after death; no changes in immunofluorescence findings occurred during this period. It is concluded that immunofluorescence provides valuable information when immunologically mediated reactions need to be clarified in necropsy kidneys.

Autopsy↗
PubMed1988

Characterization of the phenotype of smooth muscle cells in human fetal aorta on the basis of ultrastructure, immunofluorescence, and the composition of cytoskeletal and cytocontractile proteins.

The phenotype of smooth muscle cells (SMCs) in the aortic media of 7 human fetuses (14-20 weeks of gestation) was examined with transmission electron microscopy, immunofluorescence microscopy, and gel electrophoresis of the cytoskeletal and cytocontractile proteins. Ultrastructurally, virtually all medial cells were identified as SMCs having a poorly differentiated phenotype with a cytoplasm rich in rough endoplasmic reticulum and organelles, and with only a few myofilaments. All medial cells stained intensely with antibodies to vimentin, but only in a 20-week-old fetus could we find a few SMCs staining with antibodies to desmin. Nor was desmin detectable with SDS gel electrophoresis followed by immunoblotting, while clear bands corresponding to vimentin, myosin, and actin were present. In isoelectric focusing and two-dimensional gel electrophoresis beta-actin was the most prominent of the 3 actin isoforms in all cases. The present results show that SMCs in the media of fetal human aorta have a poorly differentiated phenotype, which morphologically and biochemically resembles that previously described in the aorta of fetal and newborn rat, in the arterial intima after endothelial injury, in atherosclerotic lesions, and after spontaneous modulation of medial SMCs in culture.

Actins↗