Three advanced or recurrent thyroid carcinomas invading the adjacent surrounding organs such as trachea, great vessels or anterior mediastinum were reviewed. In one patient, resection of subtotal thyroid combined with trachea including a part of cricoid cartilage was performed, and followed with end to end anastomosis. In the other two patients with SVC syndrome, a trans-sternal surgical approach was applied in order to resect a large tumor extending into the anterior mediastinum.
View Article and Find Full Text PDFJuvenile hormone production by the corpora allata of the adult female cockroach, Diploptera punctata, can be modulated by treatment with the biogenic amine, octopamine. Endogenous octopamine has been identified within the CA, using HPLC and electrochemical detection. Treatment with octopamine results in a sinusoidal, dose-dependent inhibition of JH biosynthesis by CA from day 2 virgin females, with maximal inhibition occurring at 10(-10) M and 10(-4 M.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
August 1989
Four neuropeptides that inhibit juvenile hormone synthesis by the corpora allata have been isolated from brains of the virgin female cockroach Diploptera punctata. These allatostatins are 8-13 amino acids long, are amidated, and show sequence similarity, including a 3-amino acid sequence at the C-terminal end that is common to all four peptides. The peptide sequences are as follows: allatostatin 1, Ala-Pro-Ser-Gly-Ala-Gln-Arg-Leu-Tyr-Gly-Phe-Gly-Leu-NH2; allatostatin 2, Gly-Asp-Gly-Arg-Leu-Tyr-Ala-Phe-Gly-Leu-NH2; allatostatin 3, Gly-Gly-Ser-Leu-Tyr-Ser-Phe-Gly-Leu-NH2; and allatostatin 4, Asp-Arg-Leu-Tyr-Ser-Phe-Gly-Leu-NH2.
View Article and Find Full Text PDFParameters for the validation of a radiochemical assay to monitor the biosynthesis and release of methyl farnesoate (MF) by the mandibular organs (MO) of the mud crab, Scylla serrata, have been defined. On the basis of HPLC analysis, MF appeared to be the exclusive radiolabeled product of release, using [3H-methyl]methionine as precursor. HPLC of isooctane extracts of medium in which MO had been maintained similarly revealed that MF was the exclusive 3H-product and indicates that the isooctane partition assay can be employed to monitor MF release.
View Article and Find Full Text PDFSVC syndrome is occurred by the occlusion or stenosis of the superior vena cava secondary to malignant mediastinal tumor. Up to this report, surgical intervention has been thought to be difficult. Recently, extent of the tumor has been diagnosed exactly by CT scan, NMR, and angiography.
View Article and Find Full Text PDFIntracellular recording and dye injection were used to study the structure and electrophysiological properties of individual neurons that project to the corpora allata of the cockroach, Diploptera punctata. Neurons in the pars intercerebralis generate long-duration, tetrodotoxin-sensitive action potentials. Dye injection revealed two cell types.
View Article and Find Full Text PDFHigh levels of cyclic AMP were found in the corpora allata of adult female Diploptera punctata. The adenylate cyclase activator forskolin caused a rapid, reversible and dose-dependent accumulation of cAMP in the corpora allata in vitro. The sensitivity of the corpora allata to forskolin was low when juvenile hormone (JH) synthetic activity was high, and vice versa.
View Article and Find Full Text PDFTitres of juvenile hormone (JH) have been determined in both hemolymph and whole body extracts of female Diploptera punctata during the first gonotrophic cycle using a method employing gas chromatography/mass spectrometry for qualitative and quantitative analysis. JH III is the sole JH found in both adult and last instar D. punctata.
View Article and Find Full Text PDFGen Comp Endocrinol
December 1983
A direct radiochemical assay for juvenile hormone (JH) biosynthesis by the corpora allata (CA) showed that the cyclic changes in biosynthesis associated with the gonadotrophic cycle were abolished in the absence of ovaries whether or not the CA were innervated. In ovariectomized animals denervated CA synthesized JH at slightly higher rates than did innervated CA. However, the low rates of JH synthesis in ovariectomized females were sufficient to result in accumulation of vitellogenin in the hemolymph to levels twice those of normal females.
View Article and Find Full Text PDFJuvenile hormone (JH) degradation in vitro and in vivo was studied in the viviparous cockroach Diploptera punctata. In vitro studies with juvenile hormone esterase (JHE) and "general" or l-naphthyl acetate esterase (NAcE) revealed that diethyl-p-nitrophenylphosphate (paraoxon) inhibited both JHE and NAcE activity, but the latter was more sensitive and was completely inhibited at 0.1 mM.
View Article and Find Full Text PDFThe control of the decline in C16 juvenile hormone (C16JH) synthesis in the final larval stadium of the viviparous cockroach Diploptera punctata Eschscholtz was investigated to establish how nervous and humoral signals affect the activity of the corpora allata (CA) before metamorphosis. Denervation of the CA in young last instars caused an increase in the rate of JH biosynthesis as monitored by an in vitro radiochemical assay and resulted in a supernumerary larval form at the following ecdysis. However, when larval CA were transplanted into corpus allatectomized adults, they exhibited a further 5- to 10-fold stimulation in synthetic rate and supported host oocyte development at near normal rates.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
December 1981
Mating of the Teleogryllus commodus female causes increased oviposition mediated by PGE(2), which is synthesized in the female's spermatheca from the precursor, arachidonic acid, in the presence of a PG-synthesizing complex. The latter, together with sperm, is transferred from the male to the female via a spermatophore. Only nanogram quantities of PGE(2) injected into oviduct are necessary to simulate mating-induced egg release.
View Article and Find Full Text PDFInactive female corpora allata implanted into adult males become active and continue to synthesize juvenile hormone at high rates. However, when an ovary is implanted together with the corpora allata, rates of juvenile hormone synthesis decline as the oocytes complete maturation. Injections of ecdysterone mimic the effect of an implanted ovary.
View Article and Find Full Text PDFVitellogenins are yolk protein precursors that are synthesised in the liver of lower vertebrates in response to ovarian hormones, and in the fat body tissue of insects, under the influence, in most species, of juvenile hormone (JH) from the corpora allata (CA). Vitellogenins are normally restricted to females, although in male amphibians and roosters their synthesis can be induced artificially by the injection of oestrogens. Thus female specificity is maintained by hormonal differences between adult males and females.
View Article and Find Full Text PDFThe animo acids in the deproteinized haemolymph of Glossina austeni females, before and after hydrolysis, have been determined at 12 different times during the 1st 2 pregnancy cycles. Hydrolysis resulted in a large increase in the concentrations of tyrosine, phenylalanine, aspartate and lysine, indicating that these amino acids are present mainly as peptides in the haemolymph. The rate of transfer of the aromatic amino acids to the offspring, based upon the amino acid content of the larval gut, must be exceptionally high and has been estimated to be at least 7.
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