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971.
L M Fabbri M V Alessandri N De Marzo E Zocca D Paleari M Pozzan C E Mapp 《Annals of allergy》1986,56(2):171-176
We investigated the intensity and duration of the effect of a single dose of slow-release theophylline on bronchial hyperresponsiveness to ultrasonically nebulized distilled water in asthma. In six subjects with a history of mild asthma, we measured airway responsiveness to ultrasonically nebulized distilled water and serum theophylline at 4, 8, and 12 hours after treatment with placebo or slow-release theophylline (10 +/- 1 mg/kg, orally). To assess bronchial responsiveness, dose-response curves were established by plotting the baseline value of FEV1 and the largest FEV1 after each doubling dose of nebulized distilled water against the dose of nebulized water. The degree of bronchoconstriction induced by ultrasonically nebulized distilled water was significantly inhibited at 4, 8, and 12 hours after treatment with theophylline, at serum levels of 14.8 +/- 4.6, 14.4 +/- 2.8, and 12.0 +/- 2.5 micrograms/mL theophylline (mean +/- SD). Tremor occurred in three patients and was associated with nausea, epigastric pain, and tachycardia in one of them. We conclude that a single dose of slow-release theophylline has a prolonged protective effect on bronchoconstriction induced by ultrasonically nebulized distilled water, but in some subjects is associated with side effects that limit its clinical usefulness. 相似文献
972.
Vincenzo Arena Fabio De Giorgio Antonio Abbate Arnaldo Capelli Domenico De Mercurio Arnaldo Carbone 《Cardiovascular pathology》2004,13(4):230-232
We report a rare case of sudden death due to cardiac tamponade following intrapericardial rupture of a main pulmonary artery dissecting aneurysm. On pathology examination, the pulmonary artery showed an intimal tear in an arterial wall area with reduced thickness. However, no degenerative, inflammatory or necrotic processes were evident within the vessel wall. Hypertrophy of the wall of vasa vasorum in the adventitia of the pulmonary artery was found, as well as bilaterally diffuse myointimal arterial hyperplasia of the lung vasculature. According to these findings, we conclude that pulmonary artery rupture occurred in a patient with chronic unrecognized primary pulmonary hypertension. 相似文献
973.
Pignatti P Ciapponi L Galle P Hansen MB Massa M Meazza C Paonessa G Novick D Ciliberto G Martini A De Benedetti F 《Clinical and experimental immunology》2003,131(2):355-363
We previously demonstrated that high levels of IL-6/sIL-6R complexes are present in sera of patients with systemic juvenile idiopathic arthritis (s-JIA) and that the amount of IL-6 estimated in the IL-6/sIL-6R complexes is markedly higher than that measured by the B9 assay. Here, we show that two additional bioassays, employing human myeloma XG-1 cells and human hepatoma Hep3B cells, detected serum IL-6 levels similar to those measured by the B9 assay and approximately 10-fold lower than the IL-6 levels estimated to be present in the IL-6/sIL-6R complex. Using an assay for the measurement of the amount of circulating IL-6 complexed with the sIL-6R and available for binding to gp130 (gp130 binding activity), we show that the IL-6/gp130 binding activity is similar to that detected by the bioassays and again significantly lower than that estimated to be present in the IL-6/sIL-6R complex. Addition of recombinant human IL-6 (rhIL-6) to sera of patients or controls results in a markedly lower increase in the gp130 binding activity in patients than in controls. Moreover, sera from s-JIA patients inhibited in a dose dependent manner the gp130 binding activity assay. These results show that sera from patients with s-JIA contain a factor, or factors, that inhibit(s) the binding of the IL-6/sIL-6R complex to gp130. This inhibitory activity does not appear to be due to soluble gp130, C-reactive protein or autoantibodies to IL-6. 相似文献
974.
Minelli A Maserati E Giudici G Tosi S Olivieri C Bonvini L De Filippi P Biondi A Lo Curto F Pasquali F Danesino C 《Cancer Genetics and Cytogenetics》2001,124(2):147-151
Two sisters are reported, both with a myelodysplastic syndrome (MDS) associated with partial monosomy 7. A trisomy 8 was also present in one of them, who later developed an acute myeloid leukemia (AML) of the M0 FAB-type and died, whereas the other died with no evolution into AML. Besides FISH studies, microsatellite analysis was performed on both sisters to gather information on the parental origin of the chromosome 7 involved in partial monosomy and of the extra chromosome 8. The chromosomes 7 involved were of different parental origin in the two sisters, thus confirming that familial monosomy 7 is not explained by a germ-line mutation of a putative tumor-suppressor gene. Similar results were obtained in two other families out of the 12 reported in the literature. Noteworthy is the association with a mendelian disease in 3 out of 12 monosomy 7 families, which suggest that a mutator gene, capable of inducing both karyotype instability and a mendelian disorder, might act to induce chromosome 7 anomalies in the marrow. We postulate that, in fact, an inherited mutation in any of a group of mutator genes causes familial monosomy 7 also in the absence of a recognized mendelian disease, and that marrow chromosome 7 anomalies, in turn, lead to MDS/AML. 相似文献
975.
Deng L Yang M Fründ S Wessel T De Abreu RA Tischfield JA Sahota A 《Molecular genetics and metabolism》2001,72(3):260-264
We have examined the mutational basis of adenine phosphoribosyltransferase (APRT, EC 2.4.2.7) deficiency (MIM 102600) in a patient of Polish origin who has been passing 2,8-dihydroxyadenine (DHA) stones since birth, but has considerable residual enzyme activity in lymphocyte extracts. The five exons and flanking regions of APRT were amplified by PCR and then sequenced. A single T insertion was identified at the intron 4 splice donor site (TGgtaa to TGgttaa:IVS4+2insT) in one allele from the proband, his mother, and brother. A G-to-T transversion in exon 5 (GTC-to-TTC:c.448G>T, V150F) was identified in the other allele, and this mutation was also present in one allele from the father and the paternal grandmother. Tru91 and AvaII digestions of PCR products spanning exons 4 and 5, respectively, confirmed the mutations. The mother was heterozygous for an intragenic TaqI site, but all other family members were homozygous for the presence of this site. IVS4+2insT, located on the allele containing the TaqI site, has been identified previously in several families from Europe, suggesting a founder effect, but the substitution in exon 5 is a novel mutation. IVS4+2insT is known to result in complete loss of enzyme activity, and our results suggest that V150F produces an enzyme that is nonfunctional in vivo but has considerable residual activity in vitro. 相似文献
976.
Apoptosis and expression of Bax, Bcl-x, and Bcl-2 apoptotic regulatory proteins in colorectal carcinomas, and association with p53 genotype/phenotype. 下载免费PDF全文
P M De Angelis T Stokke L Thorstensen R A Lothe O P Clausen 《Journal of clinical pathology》1998,51(5):254-261
AIMS: Spontaneous apoptosis and expression of the apoptotic regulatory proteins Bax, Bcl-x, and Bcl-2 were investigated in 50 colorectal carcinomas. The p53 genotypes/phenotypes and BAX genotypes were also determined, and possible associations of these with apoptosis and/or with expression of the different apoptotic regulatory proteins were studied. METHODS: Terminal deoxynucleotidyl transferase (TdT) mediated dUTP labelling of DNA fragments was used to detect apoptotic tumour cells in sections and peroxidase immunohistochemistry was used to assess protein expression. p53 genotype/phenotype was determined using constant denaturant gel electrophoresis/immunoblotting and bax genotype was determined using polymerase chain reaction based methods. RESULTS: The distribution of tumour apoptotic indices was bimodal with a natural cut off at 1.0% (range, 0.0-5.4%); the median fraction of apoptotic tumour cells was 0.8%. Tumour apoptosis was not associated significantly with tumour DNA ploidy status. Normal mucosal tissue had less than 0.1% apoptotic cells. Staining intensities for Bax, Bcl-x, and Bcl-2 were strong; that is, equivalent to or greater than positive normal mucosal cells, in 11 of 50, 20 of 49, and 20 of 48 carcinomas. Frameshift mutations in the bax gene were detected in three of 42 tumours analysed, all of which were DNA diploid, and Bax protein expression in these tumours was absent or very low. Bax, Bcl-x, and Bcl-2 protein expression were not correlated with tumour apoptosis or tumour DNA ploidy status. p53 was expressed in 34 of 50 tumours and p53 gene mutations were detected in 22 of 29 p53 positive tumours analysed. Apoptosis was significantly lower in a greater number of p53 positive tumours than p53 negative tumours. In addition, Bcl-2 protein expression was significantly higher in a greater number of p53 positive tumours compared with p53 negative tumours. Bax and Bcl-x protein expression were not significantly associated with p53 phenotype/genotype. CONCLUSIONS: The results indicate that acquisition of a p53 phenotype is associated with lower spontaneous apoptosis and higher expression of Bcl-2. The results also suggest that p53 is not a major determinant for Bax expression in colorectal carcinomas in vivo. 相似文献
977.
C. F. Pauwels C. Van den Broecke J. M. Demeyer C. R. De Potter 《Virchows Archiv : an international journal of pathology》1998,432(3):299-300
This case report describes a chondroma of the bladder in a 63-year-old woman with clinical complaints of pain in the left
fossa iliaca. The lesion was a tumour with a lobulated growth pattern composed of chondrocytes embedded in a chondroid matrix.
Neither mitotic figures nor increased cellularity were present. Nuclei were inconspicuous. Immunohistochemical examination
showed reactivity for S100 and vimentin.
Received: 22 April 1997 / Accepted: 25 August 1997 相似文献
978.
Identification of the multiple endocrine neoplasia type 1 (MEN1) gene. The European Consortium on MEN1 总被引:10,自引:0,他引:10
Lemmens I; Van de Ven WJ; Kas K; Zhang CX; Giraud S; Wautot V; Buisson N; De Witte K; Salandre J; Lenoir G; Pugeat M; Calender A; Parente F; Quincey D; Gaudray P; De Wit MJ; Lips CJ; Hoppener JW; Khodaei S; Grant AL; Weber G; Kytola S; Teh BT; Farnebo F; Thakker RV 《Human molecular genetics》1997,6(7):1177-1183
979.
Bals-Pratsch M; De Geyter C; Muller T; Frieling U; Lerchl A; Pirke KM; Hanker JP; Becker-Carus C; Nieschlag E 《Human reproduction (Oxford, England)》1997,12(5):896-904
Preliminary data have suggested that female infertility due to corpus
luteum insufficiency may be caused by subclinical hypothyroidism
[exaggerated thyroid-stimulating hormone (TSH) response to thyrotrophin-
releasing hormone (TRH) stimulation]. L-Thyroxine supplementation has been
recommended to achieve pregnancies in subclinical hypothyroid women. This
controlled study was carried out in order to investigate the biochemical
diagnosis of subclinical hypothyroidism as a possible infertility factor.
Five infertile patients (aged 25-36 years) with subclinical hypothyroidism
(n = 4, stimulated TSH >20 microU/ml) or primary hypothyroidism (n = 1)
and five healthy controls (aged 22-39 years) with normal thyroid function
(stimulated TSH <15 microU/ml), regular cycles and no history of
infertility were studied in the early follicular phase. In the pre-study
evaluation, eight of 23 volunteers (34.8%) had to be excluded because of
subclinical hypothyroidism with stimulated TSH values (TSHs) >15
microU/ml. Cycle function of patients and controls was compared by the
method of LH pulse pattern analysis. Therefore blood samples were drawn
every 10 min during a 24 h period. Sleep was recorded from midnight to 7
a.m. Repetition of the TRH tests at the end of the 24 h blood sampling
period confirmed the difference in stimulated TSH values of the two study
groups. Pulse analysis for luteinizing hormone (LH), TSH and prolactin
showed no differences between patients and controls for pulse frequency,
amplitude, height, length, area under curve (AUC) and the 24 h mean. Even
the hypothyroid patient had a normal LH pulse pattern. Additional
measurement of melatonin in pooled sera every 30 min gave the
well-documented diurnal profiles during day and night for both groups.
Patients had significantly higher melatonin values at seven time points
during the night. Peaks for LH, TSH, prolactin and cortisol were correlated
with the sleep stages wake, rapid eye movement, 1 + 2 and 3 + 4. We
concluded that corpus luteum insufficiency in female infertility cannot be
explained by subclinical hypothyroidism and thus should not be treated with
L-thyroxine for fertility reasons.
相似文献
980.
Regulation of the density of spermatogonia in the seminiferous epithelium of the Chinese hamster: I. Undifferentiated spermatogonia 总被引:1,自引:0,他引:1
The topographical arrangement of the clones of A single, A paired, and A aligned (As, Apr, and Aal) spermatogonia on the basement membrane of seminiferous tubules of the Chinese hamster was studied. It was found that at least some of these clones are not distributed at random as clones of similar cell number were often seen in clusters. Areas were found with few or many As spermatogonia. Also, clusters of Apr spermatogonia were found, indicating that in such an area many As spermatogonia more or less synchronously formed Apr spermatogonia. Since clusters of clones of 16 Aal spermatogonia were observed, it can be concluded that these clusters of Apr spermatogonia may proliferate in at least a roughly synchronous way. It was found that over large areas the densities of undifferentiated spermatogonia may be very low or high in comparison to the mean density in the animal. Whether the ratio of self-renewal and differentiation of the stem cells changed locally in response to the high or low density of undifferentiated spermatogonia in particular areas was investigated. No indications for a regulatory mechanism to keep the density of stem cells and/or the density of undifferentiated spermatogonial clones at a certain level could be detected in the normal Chinese hamster. This lack of regulation was at least partly responsible for the widely different numbers of A1 spermatogonia that were formed in the various areas studied in stage IX. 相似文献