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691.
A simple co-culture bioassay system was used to investigate whether or not the anatomical origin affected the ability of epithelial cells from the human uterine (Fallopian) tube to 'bind' spermatozoa. This study was also used to identify some of the factors which may be involved in the regulation of sperm-epithelial interactions in vitro by comparing different tissue culture models and assessing the effect of oestradiol concentration. Epithelial explants harvested from different regions of human uterine tubes were co-incubated with a known concentration of motile donor spermatozoa. All results were adjusted to reflect a standard sperm concentration of 5 x 10(6)/ml. More spermatozoa associated per field of isthmic compared to ampullary epithelium [isthmus 9.5 +/- 0.9, ampulla 7.1 +/- 0.7 (mean +/- SEM); n = 36, P < 0.05, ANOVA] and cells from post-menopausal patients had an apparently reduced ability to bind spermatozoa [isthmus 5.5 +/- 2.0, ampulla 4.3 +/- 1.4 (mean +/- SEM); n = 4]. Neither menstrual cycle stage nor addition of mid-cycle concentrations of 17beta-oestradiol (750 pmol/l) affected the number of spermatozoa which bound to epithelium from either tubal region. In addition, the number of spermatozoa which bound per field of polarized explants was greater (P < 0.05) than that bound to dissociated primary and passaged epithelial cell monolayers. This report is the first to provide evidence suggestive of a role for sperm- epithelial binding in the formation of an isthmic sperm reservoir in the human uterine tube. Results also indicate that oestrogen is not involved in the regulation of these interactions, and that cell polarity is an important factor for such associations in vitro.   相似文献   
692.
Coffin–Lowry Syndrome (CLS) is an X-linked syndromic form of mental retardation associated with skeletal abnormalities. It is caused by mutations of the Rsk2 gene, which encodes a growth factor regulated kinase. Gene deletion studies in mice have shown an essential role for the Rsk2 gene in osteoblast differentiation and function, establishing a causal link between Rsk2 deficiency and skeletal abnormalities of CLS. Although analyses in mice have revealed prominent expression of Rsk2 in brain structures that are essential for learning and memory, evidence at the behavioral level for an involvement of Rsk2 in cognitive function is still lacking. Here, we have examined Rsk2-deficient mice in two extensive batteries of behavioral tests, which were conducted independently in two laboratories in Zurich (Switzerland) and Orsay (France). Despite the known reduction of bone mass, all parameters of motor function were normal, confirming the suitability of Rsk2-deficient mice for behavioral testing. Rsk2-deficient mice showed a mild impairment of spatial working memory, delayed acquisition of a spatial reference memory task and long-term spatial memory deficits. In contrast, associative and recognition memory, as well as the habituation of exploratory activity were normal. Our studies also revealed mild signs of disinhibition in exploratory activity, as well as a difficulty to adapt to new test environments, which likely contributed to the learning impairments displayed by Rsk2-deficient mice. The observed behavioral changes are in line with observations made in other mouse models of human mental retardation and support a role of Rsk2 in cognitive functions. Edited by Andrew Holmes  相似文献   
693.

Background

Perception of midline diastema differs among individuals and cultures. To some, it is a feature of beauty, while to others it is aesthetically appalling. From a scientific point of view, midline diastema is a deviation from normal adult dentition. It is not uncommon among some African natives to find individuals demanding for artificially created midline diastema from dental practitioners.

Objective

To present a rare case of pulpal necrosis involving maxillary and mandibular central incisors as a result of poorly executed teeth modification in a bid to create upper and lower midline diastemata.

Result

A 23-year old lady presented with history of spontaneous, sharp, persistent pain associated with palatal swelling and discharging sinus of two weeks duration in relation to maxillary central incisors (11, 21). The complaint was preceded by a history of recurrent pain in relation to 11, 21, 31 and 41 which started soon after obtaining artificially created maxillary and mandibular midline diastemata from a dental quack. Periapical x-ray revealed periapical radiolucency in relation to 21 and 41. Vitality test confirmed necrotic pulp in the lower central incisors. The affected teeth were scheduled for root canal therapy (RCT) and porcelain fused to metal crown. The RCT of 11 and 21 had been completed but further treatment stalled due to financial constraint.

Conclusion

This is a case of obsession for midline diastema, poor dental health education, and illegal dental practice.  相似文献   
694.
BACKGROUND: The study aimed to determine whether allergic conditions accompany analgesic intolerance. METHODS: A total of 132 analgesic-intolerant patients with bronchial asthma admitted to the adult allergy unit from January 1991 to October 1997 and 103 patients with bronchial asthma randomly selected from among the asthmatics referred to our department between January and October 1997 were enrolled in the study. Those having analgesic intolerance and bronchial asthma were accepted as group I; patients having only asthma were accepted as group II. A standard questionnaire was completed for all the patients. Physical examination, routine skin prick tests, determination of total IgE levels and blood type, and oral analgesic provocation tests were also performed. RESULTS: The results showed that some allergic conditions were significantly more common in group I (22.7% and 7.8% for food allergy/intolerance [P<0.05], 16.7% and 7.8% for antibiotic allergy, 16.7% and 2.9% for dermographism, 9.8% and 1.0% for metal allergy, and 9.1% and 1.0% for chronic urticaria for groups I and II, respectively [P<0.001]). In addition, the mean of the total IgE level in the serum was higher in group I than group II (77.6 and 53.7 IU/ml; P<0.05), and the cumulative analgesic consumption was more in group I (14.2+/-17.1 and 9.1+/-12.5 boxes; P<0.05). CONCLUSIONS: Dermographism; chronic urticaria; antibiotic, metal, and food allergy; high levels of total IgE; and a high amount of cumulative analgesic consumption may be the conditions accompanying analgesic intolerance in asthmatics.  相似文献   
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