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51.
Colostrinin: a proline-rich polypeptide (PRP) from ovine colostrum and its nonapeptide active fragment (NP) induce maturation and differentiation of murine thymocytes, formation of helper cells from PNAhigh thymocytes and cytotoxic T cells from PNAlow thymocytes. These processes are accompanied by changes in expression of receptors for peanut agglutinin (PNA), PNAhigh thymocytes were transformed into PNAlow cells, and vice versa. It was shown, in various laboratories, that sialyltransferases are involved in the transformation of PNAhigh thymocytes into PNAlow cells. To find out whether the expression of receptors for PNA on murine thymocytes might also be influenced by other enzymes, we decided to study the effect of PRP and NP on sialidase and beta-galactosidase activities in these cells. The results obtained showed that the most of sialidase activity of murine thymocytes is present in the plasma membrane compartments. Both thymocyte subpopulations PNAhigh and PNAlow, showed similar sialidase activity, which was not affected either by PRP or NP. In contrast to sialidases, most of beta-galactosidase activity was present in the cytosol. PNAhigh, thymocytes showed a higher beta-galactosidase activity than PNAlow cells. Incubation of immature, PNAhigh, thymocytes with PRP or NP enhanced the beta-galactosidase activity in these cells. The presented results suggest that sialidases seem not to be involved in modulation of surface sialic acid content during murine thymocyte maturation. On the other hand, stimulation of activity of beta-galactosidase in PNAhigh, immature thymocytes by PRP and NP suggests that beta-galactosidase in murine thymocytes might be involved in transformation of PNAhigh into PNAlow cells. 相似文献
52.
J Zhang P Alfonso NR Thotakura J Su M Buergin D Parmelee AW Collins M Oelkuct S Gaffney S Gentz DP Radman GF Wagner R Gentz 《Canadian Metallurgical Quarterly》1998,12(3):390-398
Pustulosis palmoplantaris (PPP) is a common chronic skin disease, which is very resistant to treatment. It is not known why the lesions are located in the palms and soles. There are few studies of the disease and in particular studies of the histology. Fifty-nine patients with PPP answered a questionnaire concerning their medical history and 39 of them were clinically examined. Biopsy specimens were taken from involved skin in 22 of the 39 patients and studied immunohistologically for tryptase+ mast cells, EG2+ eosinophils, lipocalin+ neutrophils and CD3+ T lymphocytes. The sweat gland and sweat duct were visualized with AE1/AE3 antibody (cytokeratins 1-8, 10, 14/15, 16, 19). In addition to neutrophils in the pustule and lymphocytes in the upper dermis, there were also large numbers of mast cells and eosinophils in the subpustular area. Numerous eosinophils were present in the pustule. The epidermal part of the eccrine duct was not detectable in any of the specimens from patients with PPP but was present in all of the nine control persons (including two smokers). The results indicate that the acrosyringium is involved in the inflammation and also that mast cells and eosinophils participate in a hitherto unknown way. Of the 39 patients clinically examined, two had previously diagnosed thyroid disease and two had gluten hypersensitivity. Seventeen had one or several abnormal serum concentrations of thyroid-stimulating hormone, thyroxin, antibodies against thyroglobulin or thyroperoxidase and 10 had immunoglobulin (Ig) A antibodies to gliadin. The mean +/- SD for serum IgA and for eosinophil cationic protein was increased. From the questionnaire the most notable finding was that 56 of the 59 patients had been or still were smokers, all of whom had started smoking before the first signs of PPP. We hypothesize that the acrosyringium might be the target for the inflammation and that PPP is linked to autoimmune thyroid disease and smoking. 相似文献
53.
Metabolic bone disease was diagnosed in an 11-month-old female common marmoset (Callithrix jacchus). It was depressed, reluctant to move, and was cachectic and small for its age. Laboratory findings included anaemia, azotaemia and an inverse calcium to phosphorus ratio. The radiological findings showed simultaneous signs of osteomalacia and soft-tissue calcification. There was decreased bone density with lytic areas in the pelvis and femur, and severe bilateral nephrocalcinosis. Postmortem examination revealed marked focal dystrophic calcification of the epi- and myocardium. Calcium and vitamin D3 deficiency (nutritional secondary hyperparathyroidism) was the most likely cause of the osteomalacia. 相似文献
54.
The authors present a patient with complete laryngotracheoesophageal cleft and concurrent left lung agenesis and microgastria. Prenatal ultrasound scan showed polyhydramnios and a hypertrophic right lung. The authors propose that the combination of right lung hypertrophy, polyhydramnios, and microgastria in the absence of a competent laryngeal mechanism may suggest that the preferential path for swallowed amniotic fluid was into the lung, rather than the normal route through the stomach. This case illustrates the prenatal findings suggestive of complete laryngotracheoesophageal cleft and lung agenesis, and suggests a potential causal relationship between shunting of swallowed amniotic fluid into the bronchial tree and prenatal lung hypertrophy and microgastria. 相似文献
55.
WJ King CJ Brooks R Holder P Hughes D Adu CO Savage 《Canadian Metallurgical Quarterly》1998,112(3):539-546
The cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channel has been identified in the cardiac muscle of a number of mammalian species, including humans. The goal of this study was to begin quantifying the structural requirements necessary for arylaminobenzoate block of the CFTR channel. The cardiac cAMP-dependent Cl- current (ICl) was measured using the whole-cell arrangement of the patch-clamp technique in guinea pig ventricular myocytes during stimulation of protein kinase A with forskolin. At drug concentrations below the IC50 value for channel block, reduction of ICl by the arylaminobenzoates occurred in a strongly voltage-dependent manner with preferential inhibition of the inward currents. At higher drug concentrations, block of both the inward and outward ICl was observed. Increasing the length of the carbon chain between the benzoate and phenyl rings of the arylaminobenzoates resulted in a marked increase in drug block of the channel, with IC50 values of 47, 17, and 4 microM for 2-benzylamino-5-nitro-benzoic acid, 5-nitro-2-(2-phenylethylamino)-benzoic acid, and 5-nitro-2-(3-phenylpropylamino)-benzoic acid (NPPB), respectively. Increasing the carbon chain length further with the compound 5-nitro-2-(4-phenylbutylamino)-benzoic acid, caused no additional increase in the potency of drug block (IC50 = 4 microM). Inhibition of ICl by the arylaminobenzoates was modulated by the pH of the external solution; increasing the pH from 7.4 to 10.0 greatly weakened NPPB block, whereas decreasing the pH to 6.4 enhanced block. In addition, block of ICl was observed during intracellular dialysis of NPPB, and this action was not affected by raising the external pH. 相似文献
56.
MA Antonysamy RJ Steptoe A Khanna WA Rudert VM Subbotin AW Thomson 《Canadian Metallurgical Quarterly》1998,160(8):4106-4113
C3H (H2k) mice received 50 x 10(6) B10 (H2b) bone marrow (BM) cells either alone or with flt-3 ligand (FL) (10 microg/day), tacrolimus (2 mg/kg/day), or both agents for 7 days. Donor MHC class II+ (IAb+) cells were quantitated in spleens by immunohistochemical analysis, and donor class II DNA detected in BM by PCR. Donor cells were rare in the BM alone and BM + FL groups, whereas there was a substantial increase in chimerism in the BM + tacrolimus group. Addition of FL to BM + tacrolimus led to a further eightfold increase in donor cells and enhanced donor DNA compared with the BM + tacrolimus group. This increase in donor cells was almost 500-fold compared with BM alone. C3H recipients of B10 heart allografts given perioperative B10 BM and tacrolimus (days 0-13) exhibited a markedly extended median graft survival time (MST, 42 days) compared with those given tacrolimus alone (MST, 22 days). Addition of FL (10 microg/day; 7 days) to BM + tacrolimus prevented the beneficial effect of donor BM (MST, 18 days). BM alone or BM + FL resulted in uniform early heart graft failure (MST < 8 days). Functional studies revealed maximal antidonor MLR and CTL activities in the BM- and BM + FL-treated groups, with minimal activity in the tacrolimus-treated groups. Thus, dramatic growth factor-induced increases in chimerism achieved under cover of immunosuppression may result in augmented antidonor T cell reactivity and reduced graft survival after immunosuppressive drug withdrawal. With FL, this may reflect striking augmentation of immunostimulatory dendritic cells. 相似文献
57.
We report an iatrogenic corneal ectasia that developed after laser in situ keratomileusis (LASIK) in a case of forme fruste keratoconus. One month postoperatively, corneal topography revealed a central steep area that showed rapid progression. Visual acuity in the eye decreased from 20/20 to 20/80. Corneas with forme fruste keratoconus may have altered biomechanical properties compared with normal corneas. Forme fruste keratoconus may be a contraindication for LASIK. 相似文献
58.
WR Kirkpatrick RK McAtee SG Revankar AW Fothergill DI McCarthy MG Rinaldi TF Patterson 《Canadian Metallurgical Quarterly》1998,36(5):1330-1332
A simple screening method for fluconazole susceptibility of Cryptococcus neoformans using 2% dextrose Sabouraud dextrose agar (SabDex) with fluconazole was compared to the National Committee for Clinical Laboratory Standards (NCCLS) broth macrodilution method. By this method, fluconazole-susceptible C. neoformans isolates are significantly smaller on medium with fluconazole than on fluconazole-free medium. Isolates with decreased susceptibility have normal-size colonies on medium containing fluconazole. The 48-h NCCLS broth macrodilution MICs (NCCLS MICs) for isolates with normal-size colonies on 8- or 16-microg/ml fluconazole plates were predicted to be > or =8 or > or =16 microg/ml, respectively. On medium with 16 microg of fluconazole per ml, all strains (84 of 84) for which the NCCLS MICs were <16 microg/ml were correctly predicted, as were all isolates (7 of 7) for which the MICs were > or =16 microg/ml. Agar dilution appears to be an effective screening method for fluconazole resistance in C. neoformans. 相似文献
59.
IK Temple RJ Gardner DO Robinson MS Kibirige AW Ferguson JD Baum JC Barber RS James JP Shield 《Canadian Metallurgical Quarterly》1996,5(8):1117-1121
Transient neonatal diabetes mellitus (TNDM) is a rare form of childhood diabetes which usually resolves in the first 6 months of life but which predisposes to type 2 diabetes of adult onset. We recently reported paternal uniparental isodisomy of chromosome 6 (UPD6) in two children with TNDM and proposed that there may be an imprinted gene important in the aetiology of diabetes on chromosome 6. We now describe two unrelated families which independently suggest that the gene is imprinted, is paternally expressed and maps to 6q22-q23. One family has a duplication while the other, with familial TNDM, shows linkage to a marker in this region. 相似文献
60.