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71.
Cholecystokinin-decreased food intake in rhesus monkeys 总被引:1,自引:0,他引:1
72.
Cation channels,cell volume and the death of an erythrocyte 总被引:8,自引:0,他引:8
Lang F Lang KS Wieder T Myssina S Birka C Lang PA Kaiser S Kempe D Duranton C Huber SM 《Pflügers Archiv : European journal of physiology》2003,447(2):121-125
Similar to a variety of nucleated cells, human erythrocytes activate a non-selective cation channel upon osmotic cell shrinkage. Further stimuli of channel activation include oxidative stress, energy depletion and extracellular removal of Cl–. The channel is permeable to Ca2+ and opening of the channel increases cytosolic [Ca2+]. Intriguing evidence points to a role of this channel in the elimination of erythrocytes by apoptosis. Ca2+ entering through the cation channel stimulates a scramblase, leading to breakdown of cell membrane phosphatidylserine asymmetry, and stimulates Ca2+-sensitive K+ channels, thus leading to KCl loss and (further) cell shrinkage. The breakdown of phosphatidylserine asymmetry is evidenced by annexin binding, a typical feature of apoptotic cells. The effects of osmotic shock, oxidative stress and energy depletion on annexin binding are mimicked by the Ca2+ ionophore ionomycin (1 µM) and blunted in the nominal absence of extracellular Ca2+. Nevertheless, the residual annexin binding points to additional mechanisms involved in the triggering of the scramblase. The exposure of phosphatidylserine at the extracellular face of the cell membrane stimulates phagocytes to engulf the apoptotic erythrocytes. Thus, sustained activation of the cation channels eventually leads to clearance of affected erythrocytes from peripheral blood. Susceptibility to annexin binding is enhanced in several genetic disorders affecting erythrocyte function, such as thalassaemia, sickle-cell disease and glucose-6-phosphate dehydrogenase deficiency. The enhanced vulnerability presumably contributes to the shortened life span of the affected erythrocytes. Beyond their role in the limitation of erythrocyte survival, cation channels may contribute to the triggering of apoptosis in nucleated cells exposed to osmotic shock and/or oxidative stress. 相似文献
73.
Fugger EF; Black SH; Keyvanfar K; Schulman JD 《Human reproduction (Oxford, England)》1998,13(9):2367-2370
The world's first deliveries of normal babies after use of flow cytometric
separated human sperm cells (MicroSort) for preconception gender selection
are reported. Offspring were of the desired female gender in 92.9% of the
pregnancies. Most of these pregnancies and births were achieved after
simple intrauterine insemination.
相似文献
74.
Horne G; Jamaludin A; Critchlow JD; Falconer DA; Newman MC; Oghoetuoma J; Pease EH; Lieberman BA 《Human reproduction (Oxford, England)》1998,13(11):3045-3048
Insemination with donor spermatozoa is an integral part of infertility
treatment. For the last 3 years in our unit, intrauterine insemination with
donor spermatozoa (IUID) has been used in preference to vaginal
insemination. In this retrospective study, patients were offered an initial
course of five single intrauterine inseminations with cryopreserved donor
spermatozoa and treatment was then reviewed. A total of 389 patients
received 1465 inseminations. In all, 1119 cycles were monitored using
luteinizing hormone serum analyses and 346 cycles using the urine home test
kits. The clinical pregnancy rate per insemination for the cycles monitored
by the serum assay was 18.0% (202/1119) compared with the urine cycles
(13.7%, 46/346) (P <05). The pregnancy loss rate was not significantly
different (14.4%, 29/202 and 21.7%, 10/46) (serum and urine cycles
respectively). The viable clinical pregnancy rate was significantly higher
(P <03) for the serum cycles than for the cycles using the urinary
monitoring (15.5%, 173/1119 and 10.4%, 36/346 respectively). The cycles
monitored by serum assay had a significantly higher cumulative viable
clinical pregnancy rate (P <0001) of 70.2% after nine inseminations
compared with the urine monitored cycles of 54.8%. The majority of patients
opted for the serum cycles, with a minority self-selecting the urine cycles
mainly for travelling convenience. The explanation for the significant
differences between the viable clinical pregnancy rates per insemination
and the cumulative viable clinical pregnancy rates may be due to the
sensitivity of the urine home test kit or the patients' interpretation of
the result.
相似文献
75.
Recessively inherited L-DOPA-responsive parkinsonism in infancy caused by a point mutation (L205P) in the tyrosine hydroxylase gene 总被引:4,自引:0,他引:4
76.
Connexins are homologous four-transmembrane-domain proteins and major components of gap junctions. We recently identified mutations in either GJB3 or GJB4 genes, encoding respectively connexin 31 (Cx31) or 30.3 (Cx30.3), as causally involved in erythrokeratodermia variabilis (EKV), a mostly autosomal dominant disorder of keratinization. Despite slight differences, phenotypes of EKV Mendes Da Costa (Cx31) and EKV Cram-Mevorah (Cx30.3) show major clinical overlap and both Cx30.3 and Cx31 are expressed in the upper epidermal layers. These similarities suggested to us that Cx30.3 and Cx31 may interact at a molecular level. Indeed, expression of wild-type Cx30.3 in HeLa cell resulted only in minor amounts of protein addressed to the plasma membrane. Mutant Cx30.3 was hardly detectable and disturbed intercellular coupling. In sharp contrast, co-expression of both wild-type proteins led to a gigantic increase of stabilized heteromeric gap junctions. Furthermore, co-expressed wild-type Cx30.3 and Cx31 coprecipitate, which demonstrates a physical interaction. Inhibitor experiments revealed that this interaction begins in the endoplasmic reticulum. These results not only provide new insights into epidermal connexin synthesis and polymerization, but also allow a novel molecular explanation for the similarity of EKV phenotypes. 相似文献
77.
Huber M Wierrani F Böhm G Hauck H Lintner F Grünberger W 《Pathology, research and practice》1999,195(1):59-64
We report an unusual case of a nodular variation of pulmonary endometriosis. To our knowledge, there is no previous report on a morphological investigation of this entity. The etiology of this rare condition is still a matter of discussion. The well-circumscribed nodular mass is composed of cells identical to, or closely resembling, those of endometrial stroma containing sparse cysts and glands. Immunohistochemically, the cells showed an extensive co-expression of cytokeratin AE1/AE3 and vimentin and were highly positive for progesterone receptor (PRICA) and estrogen receptor (ERICA). Cells lining the cysts and glands as a monolayer were reactive for Ber-Ep4, cytokeratin Pan and cytokeratin AE1/AE3 and negative to all other markers used including PRICA and ERICA. The differential diagnosis of this entity included fibrous tumor of the pleura and metastatic low-grade-endometrial-stromal-sarcoma. The morphological findings are correlated with immunohistochemical studies and results of cell image analysis. This study details the clinicopathological features of the nodular variation of pulmonary endometriosis. 相似文献
78.
An experimental verification of the recently developed XVMC code, a fast Monte Carlo algorithm to calculate dose distributions of photon beams in treatment planning, is presented. The treatment head is modelled by a point source with energy distribution (primary photons) and an additional head scatter contribution. Utility software is presented, allowing the determination of the parameters for this model using a single measured depth dose curve in water. The simple beam model is considered to be a starting point for more complex models being planned for future versions of the code. This paper is mainly focused on the influence of the different techniques on variance reduction and material property determination for dose distributions. It is demonstrated that XVMC and the simple beam model reproduce measured (by a diamond detector) relative dose distributions with an accuracy of better than +/-2% in various homogeneous and inhomogeneous phantoms. Furthermore, relative dose distributions in solid state phantoms have been measured by film. Also for these cases, measured and calculated dose distributions agree within experimental uncertainty. The short calculation time (depending on voxel resolution, statistical accuracy, field size and energy, a span of 1 min to 1 h using a present-day personal computer) and an interface to a commercial planning system will allow the implementation of the code for routine treatment planning of clinical electron and photon beams. 相似文献
79.
Treatment of keratoconjunctivitis sicca with topical androgen 总被引:6,自引:0,他引:6
Objective: Androgens have been reported to influence lipid production of sebaceous glands and even many ocular tissues. The effect of topical androgen therapy on a 54-year-old patient with keratoconjunctivitis sicca (KCS) and decreased lipid phase of the tear film is reported. Methods: For assessment of the lipid phase of the tear film, break up time (BUT) and lipid layer thickness (LLT) were monitored during 6 months before treatment as well as 3 months while using a daily topical androgen therapy. Results: During the topical androgen therapy the pathological lipid phase of the tear film was completely restored indicated by the normalisation of the values of BUT and LLT. Conclusion: These findings are consistent with animal experiments indicating that topical administered androgen can restore the decreased lipid phase of the tear film. This may open up new therapeutic strategies for KCS. 相似文献
80.
Endothelial nitric oxide synthase gene polymorphism in women with idiopathic recurrent miscarriage 总被引:7,自引:0,他引:7
Tempfer C Unfried G Zeillinger R Hefler L Nagele F Huber JC 《Human reproduction (Oxford, England)》2001,16(8):1644-1647
BACKGROUND: Lack of endothelium-derived nitric oxide is associated with vasospasm and vascular infarction. We investigated the relationship between idiopathic recurrent miscarriage and a polymorphism of the gene encoding endothelial nitric oxide synthase (NOS3). METHOD: In a prospective case-control study, 105 women with idiopathic recurrent miscarriage and 91 healthy controls were investigated. We used the polymerase chain reaction to identify the different alleles of a 27 base pair tandem repeat polymorphism in intron 4 of the NOS3 gene. RESULTS: The wild type B allele was identified on 329 out of 392 chromosomes (frequency 0.84). The polymorphic A allele was present on 63 chromosomes (frequency 0.16). The genotype frequencies were as follows: 68% (B/B), 31% (A/B) and.5% (A/A). The distribution of genotype frequencies was significantly different between the study and control groups for allele A/B heterozygotes (NOS3(A/B)) (36.7 versus 23.8%, P = 0.03, OR 1.6, 95% CI 1.1--3.8). Only one individual was homozygous for the A allele (NOS3(A/A)). She was in the study group. Between women with primary and secondary recurrent miscarriages, no statistically significant difference between the distribution of NOS3(A/B) genotypes (28 versus 34%) was observed. CONCLUSIONS: These data support a role for the NOS3 gene as a genetic determinant of the risk of idiopathic recurrent miscarriage. 相似文献