The reproductive strategy of the gregarious parasitoid,Pteromalus puparum (Hymenoptera: Pteromalidae)

Summary Pteromalus puparum is a gregarious parasitoid of many butterfly pupae. Adult size, mortality, and sex ratio of P. puparum, as a parasitoid of Papilio xuthus, were unit weight of the host. Effects of female size on fecundity, wing load, and longevity were also examined.The highest total weight of progeny from the host was attained when the number of eggs per gram of the host was approximately 150. Positive correlations were observed between the size of the females and their fecundity and wing load. The maximum longevity of the female kept with honey but without hosts was attained when the initial number of parasitoids per g of the host was 150.Considering the total fecundity of all female progeny, the reproductively most efficient number of eggs to be deposited per g of the host was estimated to be approximately 300. However, as shortage of food for the adult females strongly affects their fecundity, the reproductively most efficient number of eggs to be deposited per g of the host was about 70 when the adult female progeny was not provided with food.The optimal number of eggs to be deposited when the emale oviposits in the host under field conditions is discussed.     

Hyperthermic treatment of chromomycosis with disposable chemical pocket warmers

A case of chromomycosis in which hyperthermia proved effective is reported. The patient was a 56-year-old male bean curd maker who, without any previous history of minor trauma, developed on the extensor side of the left upper arm an eczematous lesion that underwent gradual radial expansion. The lesion showed a well-defined, 7×10 cm infiltrated erythematous plaque with the central area healed and, at the upper and lower borders, adherent scales and crusts on the surface. Histological examination revealed granulomatous changes in the dermis, as well as sclerotic cells within giant cells and microabscesses. On culturing,Fonsecaea pedrosoi was isolated. The patient was treated with disposable chemical pocket warmers, which were secured over the lesion with a rather tight elastic bandage, so that they kept the affected area warm for 24 hours a day. After a month of such hyperthermic treatment, the erythema and infiltration had decreased considerably, and microscopic examination and culture of the crusts both yielded negative results. Examination of biopsy specimens of the lesion after the third month showed that it had cicatrized. The treatment was stopped after 4 months, and no relapse occurred. We also summarize the published results of local hyperthermic treatment of chromomycosis in Japan.     

The Amusic Brain: Lost in Music,but Not in Space

Congenital amusia is a neurogenetic disorder of music processing that is currently ascribed to a deficit in pitch processing. A recent study challenges this view and claims the disorder might arise as a consequence of a general spatial-processing deficit. Here, we assessed spatial processing abilities in two independent samples of individuals with congenital amusia by using line bisection tasks (Experiment 1) and a mental rotation task (Experiment 2). Both amusics and controls showed the classical spatial effects on bisection performance and on mental rotation performance, and amusics and controls did not differ from each other. These results indicate that the neurocognitive impairment of congenital amusia does not affect the processing of space.     

Involvement of phosphatidylinositol and insulin in the coordinate regulation of proteoheparan sulfate metabolism and hepatocyte growth

A rat hepatocyte cell line was cultured in Higuchi's medium with fetal calf serum and insulin and labeled with 35SO2/4-. The cells were treated with a number of ligands to displace the heparan 35SO4 proteoglycan (HSPG) from the pericellular matrix. Maximum release was obtained with D-mannose-6-PO4 (50 mM), D-glucose-6-PO4 (50 mM), myo-inositol-2-PO4 (2-5 mM), myo-inositol hexaphosphate (2-5 mM), and DL-myo-inositol-1-PO4 (1-2 mM). D-myo-Inositol-1,3,4-(PO4)3 (1 mM) and L-myo-inositol-1-PO4 (2 mM) were intermediate in their ability to release the cell surface HSPG, whereas heparin (2 mg/ml), yeast phosphomannan (4 mg/ml), D-xylose-1-PO4 (50 mM), D-glucose-6-SO4 (50 mM), and myo-inositol hexasulfate (5 mM) were ineffective. When 35SO2/4- was added to cell cultures, the total cell surface HSPG increased linearly, but the percentage of the total cell surface [35SO4]HSPG that was released by myo-inositol-PO4 increased with time during the labeling period, reaching a maximum of 65% after 5 h. When cells were labeled for 12 h without insulin in the medium, the maximum amount of cell surface HSPG that was released by myo-inositol-PO4 was reduced to 30%. However, when cells labeled in the absence of insulin were treated with phosphatidylinositol-specific phospholipase C and then myo-inositol-PO4, the release of the cell surface [35SO4]HSPG was increased to 73%. When the [35SO4]HSPG that was released from the cell surface by treatment with myo-inositol-PO4 was added to cultures of unlabeled hepatocytes, it was taken up very rapidly and a portion of the internalized HSPG was converted to free heparan SO4 chains which appeared in the nucleus. Uptake was Ca2+- and Mg2+-independent. The amount of [35SO4]HSPG taken up was markedly reduced when the myo-inositol-PO4-releasable [35SO4]HSPG was pretreated with trypsin, thermolysin, alkaline borohydride, or alkaline phosphatase. When the cells were grown in inositol-deficient medium or in the presence of myo-inositol-PO4, the amount of heparan SO4 found in the nucleus was markedly reduced, and the cells no longer exhibited contact inhibition. These effects of myo-inositol deficiency on the growth and nuclear heparan SO4 were accentuated by addition of LiCl to the cultures to prevent phosphatidylinositol synthesis from the endogenous myo-inositol-PO4.(ABSTRACT TRUNCATED AT 400 WORDS)     

Structural analysis of N-linked oligosaccharides by a combination of glycopeptidase, exoglycosidases, and high-performance liquid chromatography

A simple, sensitive, and rapid method for the analysis of structures of N-linked carbohydrates is reported. The method involves four steps: preparation of carbohydrate chains from glycopeptides by N-oligosaccharide glycopeptidase digestion; derivatization of the reducing ends of carbohydrate chains with a fluorescent reagent, 2-aminopyridine, by using sodium cyanoborohydride; separation of oligosaccharide derivatives by reverse-phase high-performance liquid chromatography; and structural analysis of oligosaccharides by sequential exoglycosidase digestion. The elution positions of 50 standard oligosaccharide derivatives were determined by HPLC. The structure of an unknown oligosaccharide can be characterized by comparison of its elution position with those of the standard compounds. The method was applied to elucidate the structures of oligosaccharides in the myeloma IgG protein, Yot.     

Immobilization of cellulolytic and hemicellulolytic enzymes on inorganic supports

Commercial cellulase preparations from Trichoderma viride and Aspergillus niger were immobilized on porous silica glass and ceramics such as alumina and titania with titanium tetrachloride (TiCl(4)) and on their silanized derivatives with glutaraldehyde (GLUT). The amounts of the immobilized enzymes were in the range 10-50 mg/g carrier (dry) depending on the kind of carrier and immobilization method. Their activities toward carboxymethyl cellulose (CMC), xylan, aryl-beta-glucoside, and aryl-beta-xyloside were 3-53% of those of the native enzymes. The optimum pH of the enzymes shifted to the acidic side in most cases, whereas the optimum temperatures were nearly the same as those of native ones. The activity of immobilized enzyme preparations towards CMC did not change significantly during continuous operation over a periods of 60 days. Finally, xylan was hydrolyzed with the immobilized enzymes, and the sugars formed were investigated.     

The different effects of recombinant human tumor necrosis factor on rat fibrosarcoma sublines

Summary The antitumor effect of recombinant human tumor necrosis factor (rH-TNF) on two clones of rat fibrosarcoma with different metastatic potential to lymph nodes was examined. The colony formation of clone A, which has high metastatic potential, was completely inhibited by continuous exposure to rH-TNF at 50 U/ml. In contrast, colony formation of clone G, which has low metastatic potential, was not inhibited by high concentrations of rH-TNF (10,000 U/ml). The inhibitory effect of rH-TNF on colony formation by clone A was also observed with a 1-h exposure to rH-TNF. This effect was time and concentration dependent, as determined by the colony assay, ³H-thymidine uptake assay, and ⁵¹Cr-release assay. ³H-thymidine and ³H-uridine uptake per cell of clone A exposed to rH-TNF was not decreased. This suggests that the mechanisms of the antitumor effect of rH-TNF were not due to inhibition of DNA and RNA synthesis of tumor cells. In vivo growth and lymph node metastases of clone A inoculated i.p. to Donryu strain rats were completely suppressed by 14 consecutive i.p. injections of 10⁵ or 10⁶ U/kg per day of rH-TNF. On the other hand the growth of clone G was not influenced by rH-TNF administration.     

Regulation of prolactin gene expression during early pregnancy in rats

We have shown that administration of estrogen which increases prolactin (PRL) synthesis in the rat may be mediated by an increase in poly [adenosine diphosphate ribose (ADP-ribose)] synthesis. Present investigation was attempted to study whether poly (ADP-ribose) synthesis is involved in rat PRL gene expression during early pregnancy. Anterior pituitaries were obtained on days 0, 2, 4, 6, 8, 10 and 12 of pregnancy (group C). Another group of pregnant rats was given nicotinamide, an inhibitor of poly (ADP-ribose) synthesis twice a day intra-peritoneally from day 0 to the day of sacrifice (group N). Serum estradiol (E2) concentration was determined by radioimmunoassay. PRL mRNA was measured by cytoplasmic dot hybridization using 32P-labeled cDNA. Poly (ADP-ribose) synthesis was assessed by incubating purified nuclei with 14C-nicotinamide adenine dinucleotide. The serum concentration of E2 increased between days 2 and 4, and on day 6 it decreased to the level of day 0. It remained low until day 12. No difference in the serum E2 level was observed in groups C and N. In group C, PRL mRNA increased from day 2 and remained high until day 8. In group C, poly (ADP-ribose) synthesis increased between days 2 and 4, decreased on day 6 to the level of day 0, and thereafter gradually increased until day 10. Administration of nicotinamide abolished the increase in poly (ADP-ribose) synthesis observed in group C during early pregnancy. In group N, the increase in PRL mRNA was completely suppressed. It is suggested that the increase in PRL mRNA in early pregnancy may be mediated by increased poly (ADP-ribose) synthesis.(ABSTRACT TRUNCATED AT 250 WORDS)     

Calyculin A and okadaic acid: inhibitors of protein phosphatase activity

Calyculin A and okadaic acid induce contraction in smooth muscle fibers. Okadaic acid is an inhibitor of phosphatase activity and the aims of this study were to determine if calyculin A also inhibits phosphatase and to screen effects of both compounds on various phosphatases. Neither compound inhibited acid or alkaline phosphatases, nor the phosphotyrosine protein phosphatase. Both compounds were potent inhibitors of the catalytic subunit of type-2A phosphatase, with IC50 values of 0.5 to 1 nM. With the catalytic subunit of protein phosphatase type-1, calyculin A was a more effective inhibitor than okadaic acid, IC50 values for calyculin A were about 2 nM and for okadaic acid between 60 and 500 nM. The endogenous phosphatase of smooth muscle myosin B was inhibited by both compounds with IC50 values of 0.3 to 0.7 nM and 15 to 70 nM, for calyculin A and okadaic acid, respectively. The partially purified catalytic subunit from myosin B had IC50 values of 0.7 and 200 nM for calyculin A and okadaic acid, respectively. The pattern of inhibition for the phosphatase in myosin B therefore is similar to that of the type-1 enzyme.