Immunocytochemical studies on the pituitary pars distalis of the Japanese long-fingered bat,Miniopterus schreibersii fuliginosus

Summary Immunocytochemical studies were performed to describe the characteristics of cell types and their distribution in the pars distalis of Japanese long-fingered bat, Miniopterus schreibersii fuliginosus, collected at various stages of the reproductive cycle. Six distinct cell types have been identified in the pars distalis by the unlabeled immunoperoxidase technique and by the ABC method. Growth hormone (GH) and prolactin (PRL) cells were immunostained with antisera against chicken GH and ovine PRL. The GH-immunoreactive cells were round or oval orangeophilic cells distributed throughout the pars distalis with prominent aggregation in the posterolateral region. The PRL cells were pleomorphic carminophilic cells that occurred in small groups within the central and dorsocaudal regions of the pars distalis. They were sparsely distributed in the central region of the pars distalis in the hibernating bats, but increased significantly in the pregnant and lactating bats. The adrenocorticotropic (ACTH) cells were large round or polygonal amphophilic cells in the rostroventral and ventrolateral regions of the pars distalis. The thyrotropic (TSH) cells were small rounded or polygonal and distributed mainly in the ventrolateral region of the pars distalis. Luteinizing hormone (LH) and follicle-stimulating hormone (FSH) cells were identified immunocytochemically with antisera against the specific beta subunits of ovine LH and rat FSH. There were two populations of LH and FSH cells, one aggregated in the zona tuberalis and the other scattered singly throughout the rest of the pars distalis. The aggregated cells were immunoreactive with both antisera directed to LH and FSH, while scattered cells were reactive solely with antiserum to either LH or FSH and exhibited seasonal variations. In females, the proportional volume of the pars distalis occupied by LH cells was significantly reduced during pregnancy and lactation. No evidence of involution was observed in pars distalis cells except for PRL cells in males or females during hibernation.     

Effects of two treatments on semen from different bulls on in vitro fertilization results of bovine oocytes

The semen of six different bulls was used to examine the effects of treatment with caffeine or caffeine plus Ca-ionophre on in vitro fertilization, cleavage and development into morulae of in vitro matured bovine oocytes. In vitro fertilization results (formation of both pronuclei, cleavage and development to >/= four-cell stage were significantly (P<0.01) higher using caffeine plus Ca-ionophre than those using only caffeine. The rates of fertilization and first cleavage were only slightly variable among the bulls. However, the present data showed significant variability in formation of both pronuclei (36 to 75%) of fertilized ova and development to the >/=4cell stage (39 to 71%) by different bulls. Development into morulae of ova recovered from the rabbit oviduct did not show any significant differences in relation to sperm treatments or individual bulls.     

Germination ecology of coastal plants in relation to salt environment

Responses of seed germination to salinity were examined using 37 species collected from salt marshes, cliffs, and fore (unstable) and hind (stable) sand dunes along Japanese coasts. For comparison, seed germination of nine inland species was also examined. The soil salinities in salt marshes ranged from 150 to 300 mmol/L NaCl, whereas those in fore and hind dunes ranged from 0 to 150 mmol/L NaCl, with a few exceptions. Cliff soils showed relatively high salinities up to 300 mmol/L NaCl. Ciff and foredune soils that encountered a typhoon and storm showed high salinities >300 mmol/L NaCl. Salt tolerance in seed germination of coastal plants was ordered by comparing the responses of percentage and rate of germination to salinity conditions up to 200 mmol/L NaCl, being in the order of salt marsh>cliff>foredune≅hind dune≅inland. Thse results indicate that salt tolerance in seed germination of coastal plants is closely related to the salinity conditions of their habitats. Germination experiments under favorable conditions showed that a high percentage of the seeds of salt marsh species germinate rapidly, those of diff species germinate slowly and those of foredune species exhibit a low percentage and low rate of germination. It seems that these germination characteristics contribute to the success of germination at the ‘safe site’ and the subsequent survivorship of emerged plants in their natural habitats.     

Induction of Cytoplasmic Streaming and Movement of Chloroplast Induced by L-Histidine and its Derivatives in Leaves of Egeria densa

Rotational cytoplasmic streaming in leaves of Egeria densa wasinduced by light as well as by L-histidine (L-His). During bothtreatement with light and with L-His chloroplasts on the periclinalface were dislodged and moved to the anticlinal face where rotationalcytoplasmic streaming occurred. The effective concentrationof L-His was about 0.01 mM and the effect was almost saturatedat 0.1 mM. A derivative of L-His, 3-methyl-L-histidine, wasslightly less effective than L-His. By contrast, 1-methyl-L-histidinewas almost ineffective for induction of streaming, not onlyin Egeria but also in Vallisneria. Our resutlts are in markedcontrast to Fitting's result (1936) that 1-M-L-His is more effectivethan L-His. In Egeria, 1-methyl-L-His counteracted the stimulativeeffect of L-His. 1-Methyl-L-His penetrated into leaf cells ofEgeria to the same extent as 3-methyl-L-His and to a greaterextent than L-His. This observation excludes the possibilitythat the impermeability of leaves to 1-M-L-His might be responsiblefor its ineffectiveness. 1-M-L-His did not interfere with photodinesis.Differences in the mechanism of induction of rotational streamingby L-His and by light are discussed. ⁴ Present address: Fukui Institute of Technology, Gakuen, Fukui,910 Japan (Received July 16, 1990; Accepted December 20, 1990)     

Cannibalistic feeding behavior of the brackish-water copepod Sinocalanus tenellus

Cannibalistic feeding behavior of the brackish-water copepodSinocalanus tenellus was examined in the laboratory using CI-II,CIII-IV and CVI female as predators and NI-II, NIII-IV, NV-VIand CI-II as prey. In each prey-predator combination, the ingestionrate increased with increasing prey density to an asymptoticvalue. Cannibalism took place even when phytoplankton was availableas an alternative food supply. Based on a daily ration, theoptimal prey stages for CVI females, CIII-IV and CI-II are NI-VI,NI-IV and NI-II respectively. Under average, natural prey density(10 nauplii l^–1), S tenellus can achieve only a smallfraction (max 9%) of the daily minimum food requirement by cannibalisticfeeding. However, the impact of cannibalism on naupliar survivorshipcan be significant. When adult females occur at a density of10 l^–1, the mortality due to cannibalism attains 99.2%during the naupliar stages.     

Cloning and sequence analyses of cDNAs encoding vasotocin and isotocin precursors of chum salmon,Oncorhynchus keta: evolutionary relationships of neurohypophysial hormone precursors

Summary The nucleotide sequences of cloned cDNAs were used to determine the primary structures of the precursors of vasotocin (sVT) and isotocin (sIT) from the hypothalamus of the chum salmon,Oncorhynchus keta. Two different cDNAs were obtained for each of sVT and sIT precursors (sVT-I and sVT-II; sIT-I and sIT-II). Both sVT and sIT precursors were found to contain a signal peptide and hormone that is connected to a neurophysin by a Gly-Lys-Arg sequence. Northern and Southern blot analyses showed that the sVT and sIT genes are expressed by the same chum salmon hypothalamus, but not by the liver and kidney. Microheterogeneity was found in the nucleotide and amino acid sequences of sVT precursors between our results and the previously reported data (Heierhorst et al. 1990). The conspicuous difference is the occurrence of a stop codon in the middle of sVT-II cDNA. The carboxyl termini of both sVT and sIT neurophysins are about 30 amino acids longer than neurophysins of toad and mammalian neurohypophysial hormone precursors. Although these extended regions do not contain a glycosylation site, they show striking similarity with the glycopeptide moiety (copeptin) of toad vasotocin and mammalian vasopressin precursors. The central portion of the neurophysins shows highest homology among corresponding regions of sVT and sIT precursors. Moreover, calculation of nucleotide substitution rates suggests that a recent gene conversion may have occurred which encompasses the exon that encodes the central segment of the sVT and sIT precursors. A possible pathway for the evolution of precursor molecules of neurohypophysial hormones is discussed.Abbreviations AVP vasopressin - C carboxyl - h human - IT isotocin - MT mesotocin - N amino - OXT oxytocin - S chum salmon - SDS sodium dodecyl sulfate - t toad - VT vasotocin     

Association of Lps gene with natural resistance of mouse macrophages against Legionella pneumophila

We have cloned a 1.6-kb region of chromosomal DNA from Thermoplasma acidophilum into Escherichia coli using as a probe part of the Methanococcus vannielii fus-gene. The sequence of the clone was highly homologous to part of the corresponding Methanococcus vannielii gene. By chromosome walking, a 4.7-kb EcoRI fragment containing the complete gene was isolated. Nucleotide sequencing revealed an open reading frame of 2196 nucleotides. The deduced amino acid sequence contains the known peptide sequence around the ADP-ribosylation site of T. acidophilum elongation factor 2, which unequivocally confirms that the fus-gene has been cloned. The amino acid sequence was compared to that of hamster and E. coli, as well as to known archaebacterial EF-2 sequences.     

Cervicovaginal and endometrial cytology in ovarian cancer

The clinical significance of cytologic examination was studied in 114 patients with ovarian cancer who had received preoperative cytologic examinations. The overall positive rate of the cytologic examinations was 26.3% (30 of 114): 22 (19.3%) of the 114 cases had positive cervicovaginal smears while 13 of 31 endometrial aspiration smears (41.9%) were positive. The positive rate was not related to the volume of ascites but rather to its presence or absence. Thus, if ascites was observed, the positive rate was about 2.1 times higher than if it was absent. In two of four cases of ovarian cancer with no endometrial invasion but a positive cytologic examination of ascitic fluid, fallopian tube specimens contained cancer cells; this suggests that ovarian cancer cells may reach the cervix and/or vagina by passing through the fallopian tube, particularly if ascites is present. Since cytologic examination, especially of endometrial aspiration smears, shows a high positive rate if ovarian cancer cells are observed in the abdominal cavity, cytology should be used as an important ancillary method for the assessment of ovarian cancer.     

Analysis of strongly acidic amino acids by the conventional amino acid analyzer: application to determination of protein-bound cysteine and glutathione

A rapid analysis method of strongly acidic amino acids and related compounds by a simple modification of an existing amino acid analyzer is presented. In this method, an anion-exchanger column (2.6 X 150 mm) packed with Hitachi 3013-N resin was developed with 0.2 M citric acid. Complete separation of phosphothreonine, phosphoserine, phosphotyrosine, cysteic acid, homocysteic acid, and glutathionesulfonic acid was achieved within 35 min, with no regeneration of the column being required. Tyrosine-O-sulfate was analyzed by the same column using 2 M sodium acetate buffer, pH 5.5. Performic acid oxidation of a variety of proteins and direct analysis of the products by this system successfully detected cysteine, homocysteine, and/or glutathione bound to proteins through disulfide bonds. This suggest the potential use of the method for analysis of the states of protein thiol groups, especially those of clinically significant mutant proteins where mutation of arginine to cysteine is rather frequently recognized.