Immunohistochemical localization of Na+-dependent glucose transporter in rat jejunum

Summary Glucose is actively absorbed via a Na⁺-dependent active glucose transporter (Na-GT) in the small intestine. We raised a polyclonal antibody against the peptide corresponding to amino acids 564–575 of rabbit intestinal Na-GT, and localized it immunohistochemically in the rat jejunum. By means of immunofluorescence staining, Na-GT was located at the brush border of the absorptive epithelial cells of the intestinal villi. Electron-microscopic examination showed that Na-GT was localized at the plasma membrane of the apical microvilli of these cells. Little Na-GT was found at the basolateral plasma membrane. Along the crypt-villus axis, all of the absorptive epithelial cells in the villus were positive for Na-GT. In addition to the brush border staining, the supranuclear positive staining, which was shown to be the Golgi apparatus by use of electron microscopy, was seen in cells located between the base to the middle of the villus. Cells in crypts exhibited little or no staining for Na-GT. Goblet cells scattered in the intestinal epithelium were negative for Na-GT staining. These observations show that Na-GT is specific to the apical plasma membrane of the absorptive epithelial cells, and that the onset of Na-GT synthesis may occur near the crypt-villus junction.     

Light and electron microscopic studies on experimental nocardia-toxicosis in mice

An exotoxin (HS-6) produced by Nocardia otitidiscaviarum isolated from certain lesions of cutaneous nocardiosis of a male 82-year-old patient induced severe injuries in the pancreas, liver, stomach, small intestine, heart, thymus and kidney of male ICR mice. Mice given Nocardia-free preparation of HS-6 at a dose of 1 mg/kg of body weight developed several autophagic vacuoles in the pancreas and liver within 20 min after the i.p. injection. Thereafter, the autophagic vacuoles increased in number and size with time. About 24 hr after the administration of HS-6, the liver showed marked accumulation of fat droplets in the cytoplasm of the hepatocytes. Although they contained abundant autophagic vacuoles in the regions of RER, there were no lipomatoses in the acinar cells of the pancreas, those of the chief cells and smooth muscle cells of the stomach, Paneth cells, goblet cells, smooth muscle cells of the small intestine, and plasma cells in the digestive tract. Biochemical examinations revealed that HS-6 had no significant effect on the protein synthesis of reticulocytes. Inoculation of the Nocardia into the mouse peritoneal cavities caused marked granulomatoses in the pancreas, liver and regional lymph nodes, but did not develop autophagic vacuoles in RER regions of these organs.     

Immunocytochemical observation of paraquat-induced alveolitis with special reference to class II MHC antigens.

The expression of class II major histocompatibility complex (MHC) antigens on alveolar epithelial cells and macrophages was investigated immunocytochemically in paraquat-induced alveolitis in the rat lung. Until 2 days after paraquat injection, class II MHC antigens were expressed on the type II alveolar epithelium without any inflammatory cellular infiltration. From the 4th to the 7th day after paraquat injection, class II MHC antigen-positive macrophages increased in the alveolar spaces, whereas the expression on the type II alveolar epithelium became obscure. Over 10 days after the injection, interstitial fibrosis progressed and the intra-alveolar inflammatory infiltrates decreased. Epithelial cells lining the thickened fibrous septa no longer expressed class II MHC antigens. These results suggest that chemical stimuli can induce class II MHC antigen expression on the type II alveolar epithelium in the early stage of cellular injury, followed by inflammatory infiltration and interstitial fibrosis.     

Spawning tactics of paired males of the dark chub,Zacco temmincki,reflect potential fitness costs of satellites

Synopsis Paired males of the dark chub, Zacco temmincki, buried released eggs by vibrating their anal fin, but this behavior was prevented and eggs were cannibalized when many satellites (males and females) were present. A number of satellite males also caused a loss to paired males in sperm competition on spawning grounds far from shelters. Paired males followed repeating tactics, which were defined as successive spawning acts at the same redd, in most cases, but occasionally did shifting tactics which refer to spawning acts conducted successively at different redds. The proportion of the shifting tactic was not correlated with the dominance status of paired males. The shifting tactic was not advantageous in performing spawnings frequently. The calculation of the total advantage of both tactics indicated that the shifting tactic itself was not more beneficial than the repeating tactic at any density of satellites. Since a number of satellites stayed around the redd when no spawning pair was present, or pursued a pair or a single dominant male moving between spawning grounds, the occasional shifting tactics of paired males functioned to confuse and disperse satellites. The spawning tactics of paired males apparently reflected potential fitness costs of satellites. Paired males mainly spawned at the redds near shelters, despite the fact that more satellites were present to devour eggs, presumably because they could obtain many females and monopolize fertilizations.     

Phylogeny of gymnosperms inferred fromrbcL gene sequences

Partial nucleotide sequences of the large subunit of ribulose-1,5-bisphosphate carboxylase (rubisco) gene (1333 base pairs: about 90% of the gene) from several seed plants were determined. Phylogenetic trees based on amino acid sequences were inferred by using the neighbor joining and maximum likelihood methods. The results indicate (1) monophyly of gnetum group (Ephedra, Gnetum, Welwitschia), (2) monophyly of extant gymnosperms containing gnetum group, which contradicts the results of morphological data.     

Study on placental transmission of Pneumocystis carinii in mice using immunodeficient SCID mice as a new animal model.

Placental transmission of Pneumocystis carinii in mice was examined in 39 animals obtained by caesarean section from 17 pregnant SCID females experimentally infected with P. carinii. When examined with toluidine blue O, DAPI and immunofluorescent antibody stains, P. carinii was detected in the lungs of infected mothers but not in the lungs of caesarean section-derived neonates even after the neonates were treated with dexamethasone for 8 weeks. However, 13 neonates born to five infected females developed P. carinii pneumonia. These results indicate that P. carinii cannot be transmitted transplacentally in mice.     

The mechanism of low susceptibility to stress in gastric lesions of spontaneously hypertensive rats.

The mechanism of low susceptibility to stress in gastric lesion formation in spontaneously hypertensive rats (SHR) was investigated focusing on the sympathetic and parasympathetic nervous systems. In the gastric tissues of SHR, norepinephrine (NE) and dopamine (DA) contents were higher, while acetylcholine content and choline acetyltransferase activity were lower than those of Wistar-Kyoto rats (WKY). Water-immersion restraint induced gastric lesions frequently in WKY (ulcer indices : 52 +/- 7mm2) but less frequently in SHR (ulcer indices : 3 +/- 1mm2). Although NE content decreased in both SHR and WKY as a result of water-immersion restraint, it remained higher in SHR than in WKY. ACh content decreased by the procedure in WKY but not in SHR. DA content was increased by the procedure in all gastric regions of SHR. The gastric lesions induced in SHR were aggravated by pretreatment with 6-hydroxydopamine, an agent for chemical sympathectomy, following decreases of NE and DA contents. These results indicate that the relative sympathetic hyperfunction, parasympathetic hypofunction and dopaminergic mechanism in the stomach contribute to the prevention of gastric lesion formation in SHR.     

Characterization and Intracellular Distribution of Pea Phytochrome I Polypeptides Expressed in E. coli

The pea phytochrome I (PI) cDNA clone, pPP1001, was expressedin E. coli. The plasmid pPP1001 contains pea PI cDNA which coversthe entire coding region with the Shine-Dalgarno consensus sequencejoined upstream of the cDNA in an expression vector pNUT6. ThepPP1001 transformants formed typical inclusion bodies when culturedat 32?C. However, when cultured at 37?C or in the presence ofisopropyl-ß-D-thiogalactopyranoside (IPTG) at 32?C,the bacteria lysed before inclusion body formation. Immuno-stainingwith anti-PI monoclonal antibody, mAP5, of transformants fixedby cold methanol showed that stainable materials were distributedin whole cytoplasmic region. When the inclusion bodies wereobserved clearly, the regions corresponding to the inclusionbodies became difficult to stain. Western blot analysis, however,showed that a ca. 100 kDa PI polypeptide was detected in thefraction from inclusion bodies and a ca. 90 kDa PI polypeptidefrom the soluble fraction. The amino acid sequence analysisof purified 100 kDa PI sample indicated that its amino terminusis blocked. However, minor signals in one experiment yieldeda sequence corresponding to the expected amino terminus of peaPI except for the initiation methionine. One of the anti-peaPI monoclonal antibodies, mAP9, that recognizes the near N-terminusof pea phytochrome was reactive to the 100 kDa polypeptide. (Received June 22, 1990; Accepted November 18, 1990)     

Distribution and characterization of diglycosyldiacylglycerol isomers with different anomeric configuration in higher plants.

The novel diglycosyldiacylglycerol (DGDG), galactosyl(beta 1----6)-galactosyl(beta 1----3')-diacylglycerol (B isomer), present in Adzuki beans was found to be distributed together with the well-known galactosyl(alpha 1----6)-galactosyl(beta 1----3')-diacylglycerol (A isomer), in all (10) of the higher plants examined. The highest levels were found in leguminous seeds were the amounts were always less than 33% of the total DGDG of mature seeds. The highest proportion of the B isomer was found in Adzuki bean seed DGDG (26-33%), with the lowest in pea seed DGDG (2%). The amounts of the B isomer in DGDG of Adzuki and kidney beans cotyledons were almost equal to those in mature seeds. Immature seeds and hypocotyls of three kinds of beans also contained the B isomer in small amounts compared with the mature beans, while only trace amounts of the isomer was found in other organs such as leaves, stems, pods, roots and generative organs of plants, except for root from kidney beans. The molecular species composition of the principal diacylglycerol moieties in the A and B isomers of DGDG were found to be significantly different among several plant seeds, although the component diacylglycerol species were qualitatively similar to each other.     

Augmentation rhinoplasty: observations on 1200 cases

Over the past 14 years, from January of 1975 to December of 1988, we have done 1263 aesthetic rhinoplasties using ear cartilage. In the field of augmentation rhinoplasty, many kinds of materials, such as bone, septal cartilage, ear cartilage, and prostheses, were used. In this paper, we limit discussion to our experience with the technique for the augmentation of the nasal dorsum using the ear cartilage and compare this with other materials. Patient ages ranged from 15 to 72 years, with an average of 24 years. Some 95 percent of patients (1199) were female, and only 5 percent (64) were male. Patients were followed for a minimum of 6 months and a maximum of 20 months, with average follow-up only 8 months. Of course, we know that this is a very short follow-up period, but we could not follow patients longer because if they had no complaint about the results at the 6-month visit, they never returned, despite our efforts. Five-hundred and ten of the 1263 patients (40 percent) had been augmented elsewhere, and the silicone prosthesis was already in place. However, 753 patients (60 percent) had no previous operation. For the 510 patients (secondary rhinoplasty patients), too-high or too-large a prosthesis was the largest complaint in number, totaling 378 cases (74 percent), and psychological dissatisfaction, such as pain or an uncomfortable sensation, was the second largest in number, totaling 104 cases (20 percent). For the 753 patients (primary rhinoplasty patients), the main complaint was too-short or too-flat a nose (100 percent).(ABSTRACT TRUNCATED AT 250 WORDS)