Comparison of Photosynthetic and Photorespiratory Enzyme Activities between Green Leaves and Colorless Parts of Variegated Leaves of a C4 Plant, Stenotaphrum secundatum (Walt.) Kuntze

The activities of enzymes involved in C⁴ photosynthesis andphotorespiration in colorless parts of variegated leaves ofStenotaphrum secundatum (Walt.) Kuntze were compared with thosein green leaves. Chlorophyll content of the colorless part wasonly about 0.3–3% of that of the green leaves. The activities of chloroplastic enzymes, pyruvate, P_i dikinase,NADP⁺-malic enzyme and NADP⁺-glyceraldehyde 3-phosphate dehydrogenasewere considerably lower in colorless tissue on a fresh weightor protein basis (the ratios of the activities in the green/colorlesstissues ranging from 5 to 20). A cytoplasmic enzyme, UDP-glucosepyrophosphorylase as well as aspartate and alanine aminotransferasesshowed comparable activities in the two types of tissue, whereasPEP carboxylase in the colorless tissue had only the one-thirdactivity of that in green tissue. Differences in activitieswere also observed for the glycolate pathway enzymes (the ratiosranging from 2 to 7 for glycolate oxidase, hydroxypyruvate reductaseand serine hydroxymethyltransferase, and 7 to 15 for catalase),while cytochrome c oxidase showed comparable activity in thetwo types of tissue. The results suggest that the deficiency of thylakoid developmentin the colorless tissue influences enzyme activities not onlyin plastids but also in other cellular compartments. ¹Present address: Institute of Applied Microbiology, Universityof Tokyo, Tokyo 113, Japan. (Received March 26, 1986; Accepted June 17, 1986)     

Evaluation of intestinal microbiota,short-chain fatty acids,and immunoglobulin a in diversion colitis

It is reported that an increase in aerobic bacteria, a lack of short-chain fatty acids (SCFAs), and immune disorders in the diverted colon are major causes of diversion colitis. However, the precise pathogenesis of this condition remains unclear. The aim of the present study was to examine the microbiota, intestinal SCFAs, and immunoglobulin A (IgA) in the diverted colon. Eight patients underwent operative procedures for colostomies. We assessed the diverted colon using endoscopy and obtained intestinal samples from the diverted colon and oral colon in these patients. We analyzed the microbiota and SCFAs of the intestinal samples. The bacterial communities were investigated using a 16S rRNA gene sequencing method. The microbiota demonstrated a change in the proportion of some species, especially Lactobacillus, which significantly decreased in the diverted colon at the genus level. We also showed that intestinal SCFA values were significantly decreased in the diverted colon. Furthermore, intestinal IgA levels were significantly increased in the diverted colon. This study was the first to show that intestinal SCFAs were significantly decreased and intestinal IgA was significantly increased in the diverted colon. Our data suggest that SCFAs affect the microbiota and may play an immunological role in diversion colitis.     

Regulation by 1alpha,25-dihydroxyvitamin D(3) of expression of stanniocalcin messages in the rat kidney and ovary.

Regulation by vitamin D(3) of expression of the genes for stanniocalcins 1 and 2 (STC-1 and STC-2) was studied and their levels were shown to be oppositely regulated in the kidney and to remain unaffected in the ovary. Female rats were treated with calcitriol, the active form of vitamin D(3), and alterations in the levels of STC-1 and STC-2 mRNA were determined by Northern blot analysis in the kidney and ovary where the STC-1-expressing cells have previously been identified by in situ hybridization histochemistry. In the kidney, calcitriol treatment increased the STC-1 mRNA levels more than 3-fold, but decreased the STC-2 message to trace levels. In the ovary, however, both STC-1 and STC-2 mRNA levels were not significantly affected by the calcitriol treatment. These results support the hypotheses that (1) STC-1 and STC-2 have opposite effects on calcium and phosphate homeostasis, namely anti-hypercalcemic and anti-hypocalcemic actions, respectively, and (2) the mammalian stanniocalcin system acquired, in addition to the role in the systemic mineral metabolism, a role in the reproduction system that operates independently of the systemic condition.     

Control of the nitrile-hydrolyzing enzyme activity in Rhodococcus rhodochrous IFO 15564: preferential action of nitrile hydratase and amidase depending on the reaction condition factors and its application to the one-pot preparation of amides from aldehydes

The reaction conditions towards the preferential action of either nitrile hydratase or amidase in the harvested whole cells of Rhodococcus rhodochrous IFO 15564 were elaborated. The amidase showed higher heat tolerance than the nitrile hydratase and, at 45 °C the amidase worked exclusively. DMSO assisted the preferential action of nitrile hydratase, however, at more than 30% (v/v) addition of DMF, the nitrile hydratase activity was completely lost and only amidase worked. A one-pot chemo-enzymatic conversion of aldehydes to amides [(1) aq. NH₃, I₂, DMSO; (2) Na₂S₂O₃; (3) harvested cells of R. rhodochrous] was established. Under these reaction conditions, most of the amidase was lost, and the incubation of the firstly formed intermediates, nitriles in aq. NH₃ was responsible for the selective inhibition of amidase. The freezing of harvested cells in an exhaustively deionized environment provided a long-term preservable “ready to use” for the organic chemist.     

R3: Invasive salivary duct carcinoma ex pleomorphic adenoma of the parotid gland: a teaching case giving rise to the genuine diagnostic difficulty on an inadequate cytology specimen

ABSTRACT: A history of a recent rapid increase in long-standing swelling mass was presented in the right parotid gland of an 85-year-old male. The inadequate cytologic specimens contained few small clusters of three-dimensional malignant epithelial cells having hyperchromatic pleomorphic nuclei and prominent nucleoli, adjacent to a cluster of benign monomorphic myoepithelial cells. We first interpreted it merely as an adenocarcinoma, not otherwise specified. A radical parotidectomy was performed, and gross examination revealed an encapsulated and firm tumor lesion, looking grayish-blue to yellowish-white, focally associated with extracapsular invasion. On microscopic examination, the tumor was predominantly composed of a proliferation of highly atypical epithelial cells having abundant eosinophilic cytoplasm, often arranged in a Roman-bridge appearance with foci of comedo necrosis, alternating with extensive infiltration to adjacent stroma in a trabecular or alveolar fashion with severe vessel permeation. Within the background of pleomorphic adenoma, the carcinoma cells sometimes replaced ductal luminal cells while retaining an intact-like myoepithelial layer. Therefore, we finally made a diagnosis of invasive salivary duct carcinoma ex pleomorphic adenoma. We should be aware that owing to its characteristic features, cytopathologists might be able to determine correct diagnosis, based on multiple and adequate samplings. Virtual slides The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/2126158270695815.     

Locus prl5 improves lodging resistance of rice by delaying senescence and increasing carbohydrate reaccumulation.

We investigated the reason for carbohydrate retention in the stem of rice (Oryza sativa L.) at full-ripe stage in a near-isogenic line (NIL63) carrying prl5, which confers lodging resistance without yield loss. NIL63 showed higher lodging resistance than Nipponbare (control) without reduced yield. At heading, the carbohydrate content in the NIL63 stem (culm and leaf sheathes) was the same as in Nipponbare. At 2 weeks after heading, the carbohydrate content in NIL63 was significantly higher than in Nipponbare. At 4 weeks after heading, the carbohydrate content in NIL63 had decreased to near the level in Nipponbare. At 6 weeks after heading, NIL63 showed higher carbohydrate reaccumulation. Chlorophyll degradation in the leaf blades of NIL63 was slower, and the chlorophyll content at 6 weeks after heading was higher than in Nipponbare. These results suggest that the delay in leaf senescence by prl5 results in carbohydrate reaccumulation in the stem after grain filling, increasing lodging resistance.     

Sex- and age-specific prevalences of HBeAg and anti-HBe among HBsAg carriers with or without liver function abnormalities in Okinawa, Japan

We investigated sex- and age-specific prevalences of hepatitis B e antigen (HBeAg) and antibody to HBeAg (anti-HBe) in 1,163 carriers of hepatitis B surface antigen (HBsAg) in Okinawa, Japan, and followed them up for longer than one year in correlation with liver function abnormalities. Elevated serum transaminase levels were found in 160 (13.8%) of them. The prevalence of liver function abnormalities was significantly higher in male carriers (127/690, 18.4%) than in female carriers (33/473, 7.0%) at a P value of 0.001. In asymptomatic carriers, the prevalence of HBeAg was 13.2% and that of anti-HBe 80.0%, significantly different from 41.9% and 54.4%, respectively, in carriers with elevated transaminase levels (P less than 0.001). In asymptomatic carriers, the mean age of HBeAg-positive carriers was 16.7 years which was much lower than the 22.8 years in carriers with liver function abnormalities. The prevalence of elevated transaminase levels was significantly higher in carriers with HBeAg than in those with anti-HBe (33.8% vs. 9.7%, P less than 0.001). Based on these results, the prolonged positivity for serum HBeAg would qualify as a predictor for deteriorating liver function among HBsAg carriers.     

Marked Alteration at Midblastula Transition in the Effect of Lithium on Formation of the Larval Body Pattern of Xenopus laevis

Embryos of Xenopus laevis were exposed to 0.4 M LiCl for 5 min at various stages of development. The effect of lithium on the larval body pattern could be detected from the 2-cell to the late gastrula stage, but changed from reduction of posterior structures ("anteriorization") to reduction of anterior structures ("posteriorization") just after the 12th cleavage, the time of midblastula transition (MBT). Temporal coincidence of MBT with alteration of the effect of lithium was observed even with embryos derived from half-egg fragment, in which MBT occurs just after the 11th cleavage. These results suggest the existence of a mechanism for formation of the basic plan of the larval body whose function changes at MBT. Combinations of the pre- and post-MBT exposures to lithium induced marked posteriorization in most larvae, indicating that the basic plan is not irreversibly determined until MBT, but is fixed during post-MBT stages.     

Isolation of a novel antibody, which precipitates ribonucleoprotein complex containing threonine tRNA from a patient with polymyositis

We have isolated and characterized a novel antibody from a patient with polymyositis, which precipitates threonine tRNA and an unknown small RNA molecule from 32P-labeled HeLa extract. Fingerprint analysis showed that the human threonine tRNA precipitated was nearly identical to the murine tRNA described by Harada [(1978) Seikagaku 50, 397-411]. Nucleotide analysis suggested that the other small RNA molecule might be transfer RNA. Since phenol extraction resulted in the loss of immunoprecipitability, the protein portion was presumed to be involved in the recognition of the antigen. Immunofluorescence staining of HeLa cells with the antibody clearly demonstrated that the antigen was located predominantly in the cytoplasm.