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11.
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A cribriform plate, a perpendicular plate, and two lateral masses are major components of the ethmoid bone of mammals. Notwithstanding the noticeable bone, virtually sitting in the center of the skull, extensive modifications of the skull of modern cetaceans, especially odontocetes (toothed whales), and the lack of clarity as to what characteristics delimit each element of the ethmoid has made the problem of the nature of the cetacean ethmoid more complicated and elusive than in other, less modified mammals. Furthermore, contention as to whether a perpendicular plate of the ethmoid, or the mesethmoid, exists in all mammals including cetaceans has remained unsettled. In odontocetes, the mesethmoid has been variably identified not only as the osseous nasal septum but also as the mediodorsal region of the posterior wall of the nasal passage below the nasals, as a mass of bone encased by the vomer in front of the osseous nasal cavity at the base of the rostrum, and as a combination of some portions mentioned above. The presence or absence of the mesethmoid in various groups of mammals has attracted the attention of some biologists, and here, I demonstrate that cetaceans have no mesethmoid. The close inspection of the ontogenetic changes of the basicranial elements in cetaceans reveals that a mass of bone ensheathed by the vomer in front, or at the level of the osseous nasal cavity is actually the presphenoid. It is highly likely that in odontocetes the posterior wall of the nasal passages below the nasals consists of the combination of the frontal, the imperforated cribriform plate, the paired ectethmoids, and the vomer, the latter three of which partially concealing the presphenoid dorsally and laterally as the ontogeny proceeds. In contrast, mysticetes clearly display ethmoturbinates and a cribriform plate, which are morphologically similar to those in terrestrial mammals. J. Morphol. 277:1661–1674, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
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BACKGROUND: Aspiration biopsy cytology of thyroid tumors has been used more frequently in recent times to differentiate between malignant and benign lesions. Chromatin patterns of the tumor cell nuclei are one of most important factors for cytologic diagnosis. The interpretation of nuclear chromatin patterns is subjective and more difficult than that of nuclear size or shape. In the present report, we investigated how to detect underlying chromatin characteristics of benign and malignant thyroid tumor cells by means of texture and factor analyses. METHODS: We employed a computer-aided system in which light microscopy was combined with an image processor and monochrome camera. Using this system, 100 randomly selected cells in a Papanicolaou stained, aspiration biopsy cytologic smear in each case of 39 benign and malignant thyroid tumor cases were digitized. We applied two-dimensional and higher texture analyses with the use of co-occurrence and run-length matrices to analyze the chromatin patterns. Factor analysis was used to determine whether a large number of independent variables actually measured one or more underlying common variables. RESULTS: According to parameters with high factor-loading values, the morphologic chromatin characters were classified into three categories according to heterogeneity, contrast, and homogeneity of chromatin patterns. On the basis of analyses with these morphologic categories, nuclei of papillary carcinoma showed higher contrast of chromatin patterns than did those of the benign group. Moreover, there was a variety of contrasting chromatin patterns among cells in each papillary carcinoma case in comparison with the benign group. In contrast, follicular carcinomas showed a significant difference in the standard deviation of factor 3, which indicated more monotonous chromatin patterns among cells in each follicular carcinoma case than in each benign case. CONCLUSION: We believe that this technique, using texture and factor analyses, is useful in the detection of underlying characteristics of nuclear chromatin patterns in aspiration biopsy cytology.  相似文献   
15.
Mg(2+) buffering mechanisms in PC12 cells were demonstrated with particular focus on the role of the Na(+)/Mg(2+) transporter by using a newly developed Mg(2+) indicator, KMG-20, and also a Na(+) indicator, Sodium Green. Carbonyl cyanide p-(trifluoromethoxy) phenylhydrazone (FCCP), a protonophore, induced a transient increase in the intracellular Mg(2+) concentration ([Mg(2+)](i)). The rate of decrease of [Mg(2+)](i) was slower in a Na(+)-free extracellular medium, suggesting the coupling of Na(+) influx and Mg(2+) efflux. Na(+) influxes were different for normal and imipramine- (a putative inhibitor of the Na(+)/Mg(2+) transporter) containing solutions. FCCP induced a rapid increase in [Na(+)](i) in the normal solution, while the increase was gradual in the imipramine-containing solution. The rate of decrease of [Mg(2+)](i) in the imipramine-containing solution was also slower than that in the normal solution. From these results, we show that the main buffering mechanism for excess Mg(2+) depends on the Na(+)/Mg(2+) transporter in PC12 cells.  相似文献   
16.

Background

Irritable bowel syndrome with constipation (IBS-C) is a representative psychosomatic disorder. Several pathophysiological factors have been linked to IBS symptoms such as the modulation of gastrointestinal motility, visceral hypersensitivity, dysregulation of the gut-brain axis, genetic and environmental factors, sequelae of infection, and psychosocial disorders. It is likely that biopsychosocial aspects of IBS-C underlie its gender and age effects. However, the influence of each symptom of IBS-C by gender and age is not well understood. We hypothesized that the expression rate of each IBS-C symptom in females and in subjects aged 20–49 years was higher than that of subjects who were male and aged 50–79 years.

Methods

We conducted an internet survey of 30,000 adults from the general Japanese population. IBS-C subjects were asked to answer a questionnaire on the degree of anxiety, thoughts about bowel habits, and their dominant gastrointestinal symptoms together with exacerbation factors. The correlation between gender and age and IBS-C symptoms was analyzed.

Results

When analyzed by gender, the expression rate of abdominal discomfort, abdominal distention, and abdominal fullness was significantly higher in female than male IBS-C subjects (66.5% vs. 58.7%, p?<?0.05; 54.7% vs. 43.6%, p?<?0.01; 18.9% vs. 9.6%, p?<?0.01, respectively). When analyzed by age, the expression rate of abdominal distention and abdominal pain was significantly higher among IBS-C subjects aged 20–49 years than those aged 50–79 years (55.7% vs. 46.8%, p?<?0.05; 36.6% vs. 20.6%, p?<?0.001, respectively). In contrast, there was no gender or age differences with regard to the most common and bothersome symptom (abdominal bloating) among IBS-C subjects.

Conclusions

The expression rate of some IBS-C symptoms was higher among females and those aged 20–49 years than males and those aged 50–79 years, respectively. It is important to understand the impact of symptoms by gender and age to evaluate the pathology of IBS-C from a biopsychosocial perspective.

Trial registration

Although this survey was an anonymous internet survey, we obtained informed consent for the study as an online response. The disclosure of this study was approved by the Ethics Committee of Tohoku University Graduate School of Medicine (approval number: 2015–1-405).
  相似文献   
17.
Highly branched α-glucan molecules exhibit low digestibility for α-amylase and glucoamylase, and abundant in α-(1→3)-, α-(1→6)-glucosidic linkages and α-(1→6)-linked branch points where another glucosyl chain is initiated through an α-(1→3)-linkage. From a culture supernatant of Paenibacillus sp. PP710, we purified α-glucosidase (AGL) and α-amylase (AMY), which were involved in the production of highly branched α-glucan from maltodextrin. AGL catalyzed the transglucosylation reaction of a glucosyl residue to a nonreducing-end glucosyl residue by α-1,6-, α-1,4-, and α-1,3-linkages. AMY catalyzed the hydrolysis of the α-1,4-linkage and the intermolecular or intramolecular transfer of maltooligosaccharide like cyclodextrin glucanotransferase (CGTase). It also catalyzed the transfer of an α-1,4-glucosyl chain to a C3- or C4-hydroxyl group in the α-1,4- or α-1,6-linked nonreducing-end residue or the α-1,6-linked residue located in the other chains. Hence AMY was regarded as a novel enzyme. We think that the mechanism of formation of highly branched α-glucan from maltodextrin is as follows: α-1,6- and α-1,3-linked residues are generated by the transglucosylation of AGL at the nonreducing ends of glucosyl chains. Then AMY catalyzes the transfer of α-1,4-chains to C3- or C4-hydroxyl groups in the α-1,4- or α-1,6-linked residues generated by AGL. Thus the concerted reactions of both AGL and AMY are necessary to produce the highly branched α-glucan from maltodextrin.  相似文献   
18.
Detailed structure of the male genitalia of Anevrina is described. Hitherto unknown morphological characters of the internal sclerites relating to the epandrium and hypandrium are illustrated and elucidated. The subepandrial sclerite + bacilliform sclerites are distinctly modified, and the typical subepandrial sclerite is not recognizable. The right base of the medially shifted right surstylus is not connected to the posterior margin of the epandrium, and is directly supported by a robust bacilliform sclerite. The robust bacilliform sclerites are greatly developed inside the epandrium, and extended to three clasping components, the left surstylus, the medially shifted right surstylus and a pair of clasping lobes on the posteroventral margin of the right side of the epandrium. The upper lobe of a pair of clasping lobes on the right side of the epandrium is considered to originally have been situated on the left side and subsequently shifted to the right side. The plesiomorphic state of the clasping components relative to Anevrina is thought to be symmetrically four, comprising both the left and right surstyli and the posterior edge of both sides of the epandrium, indicating that the amazing phenomenon of cross-shifting of the clasping components has occurred in Anevrina. A cladogram generated based on the genitalic characters observed in this study shows sister groups within Anevrina, namely an Anevrina urbana-group comprised of A. urbana, A. setigera, A. olympiae, A. variabilis, A. thoracica, and an Anevrina unispinosa-group comprised of A. unispinosa, A. curvinervis, A. luggeri and A. macateei.  相似文献   
19.
The assembly of spliceosomal U snRNPs in metazoans requires nuclear export of U snRNA precursors. Four factors, nuclear cap-binding complex (CBC), phosphorylated adaptor for RNA export (PHAX), the export receptor CRM1 and RanGTP, gather at the m7G-cap-proximal region and form the U snRNA export complex. Here we show that the multifunctional RNA-binding proteins p54nrb/NonO and PSF are U snRNA export stimulatory factors. These proteins, likely as a heterodimer, accelerate the recruitment of PHAX, and subsequently CRM1 and Ran onto the RNA substrates in vitro, which mediates efficient U snRNA export in vivo. Our results reveal a new layer of regulation for U snRNA export and, hence, spliceosomal U snRNP biogenesis.  相似文献   
20.
The high expression of CD98 was reported in some normal tissues, including blood brain barrier, activated lymphocytes, the basal layer of skin, proximal tubles of kidney, placenta, testis and a wide variety of tumors. The CD98 complex consists of an 80-85kD heavy chain (4F2hc/FRP-1) and a 40-45kD light chain. CD98hc, 4F2hc, and FRP-1 are the same glycosylated protein each other and define antigenicity of CD98. LAT1, the sodium-independent L-type amino acid transporter 1, has been identified as a light chain of the CD98 heterodimer from C6 glioma cells. LAT1 also corresponds to TA1, an oncofetal antigen that is expressed primarily in fetal tissues and cancer cells such as glioma cells. Increased LAT1 expression was found in various malignancies including human gliomas. Several studies implicated the important role of LAT1 and 4F2hc in malignant transformation and carcinogenesis. The LAT1-CD98 pathway may represent a unique therapeutic target for cancer intervention.  相似文献   
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