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31.
27 patients with Cushing's disease were treated over a period of 18 years at the Departments of Medicine and Surgery, Nagoya University School of Medicine and the following results were obtained. 1) Adrenalectomy. 21 of 27 patients with Cushing's disease underwent adrenalectomy. 19 patients had total bilateral adrenalectomy and 2 patients unilateral adrenalectomy. 4 patients died, the cause of death not being related directly to adrenalectomy. 9 of 15 bilaterally adrenalectomized patients had hyperpigmentation even though they had been given substitution therapy with cortisol 20-30 mg daily. They had elevated plasma ACTH levels, which were not completely suppressed by 2 mg of dexamethasone or 2.5 mg of bromocriptine per day. 2) Adenomectomy, 5 patients had adenomectomy via the transsphenoidal approach. 3 patients were cured but one of them has required postoperative substitution therapy with cortisol for hypopituitarism for one year until today. 2 of 5 adenomectomized patients had a recurrence of Cushing's syndrome after remission for 6-8 months. One of these recurrent cases has been subsequently treated successfully with bromocriptine, a dopaminergic drug. 3) Medical treatment. 2.5 mg per day of bromocriptine has been effective in 2 patients without a pituitary adenoma and ineffective in the other 4 patients with a pituitary adenoma. 24 mg per day of cyproheptadine, an antiserotoninergic drug was not effective in any of the 4 patients with a pituitary adenoma.  相似文献   
32.
Photosensitizers produce cytotoxic reactive oxygen species (ROS) upon light illumination, but it is difficult to ablate cells of a specific type (e.g., tumor cells) in the presence of other cell populations, because of the limited precision with which light illumination can be directed to small areas. Here, we report a strategy to achieve cell type-specific ablation by using an enzyme-activated off/on switch for oxidative stress induction. In the unactivated photosensitizer, induction of oxidative stress is quenched by intramolecular electron transfer. However, the target cells express an enzyme that hydrolyzes a substrate moiety of the photosensitizer and the activated photosensitizer induces oxidative stress. As proof of concept, we designed and synthesized a xanthene-based photosensitizer, TGI-βGal, whose oxidative stress induction ability is switched on following hydrolysis reaction with β-galactosidase, a widely used gene marker. TGI-βGal could selectively ablate lacZ-positive cells, whereas it showed no toxicity to lacZ-negative cells, upon light illumination.  相似文献   
33.
A series of novel tetra-peptide motilin agonists, having the general structure H-Phe-Val-X-Ile-NH(2), were designed, on the basis of structure-activity relationship studies of motilin. Peptides, in which X is a side chain substituted tryptophan residue, have agonistic activity. H-Phe-Val-Trp(2'-CH(2)CH(2)OH)-Ile-NH(2)(7), H-Phe-Val-Trp(2'-SCH(3))-Ile-NH(2)(8), and H-Phe-Val-Trp(2'-SCH(2)CH(2)CH(3))-Ile-NH(2)(9), showed an EC(50) for contractile activity in the rabbit smooth muscle of 14.1+/-3.2, 12.9+/-4.1, and 4.6+/-1.6 microM, respectively. Interaction of the tryptophan aliphatic side chain with motilin receptor appears to influence the signal transduction via motilin receptor.  相似文献   
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Synopsis We confirmed both-ways sex change in the coral-dwelling gobies Gobiodon micropus, G. oculolineatus, G. quinquestrigatus and G. rivulatus rivulatus by mate-removal experiment in the field and by the aquarium experiment of keeping two consexual fish in a coral. Eight species of Gobiodon were found in Acropora corals on the reef flat of Sesoko Island, Okinawa, southern Japan. The 4 species mentioned above bred in monogamous pairs composed of a male and a female matched by size, and the male took care of eggs deposited on the coral branch. In G. quinquestrigatus and G. rivulatus rivulatus males were larger than females in newly formed pairs, and females grew faster than their mates until breeding. The growth-rate advantage in females seems to be the major factor in the evolution of female to male sex change. The gobies strongly depended on host corals, but they moved between the corals after mate loss or coral death to form new pairs. This provides opportunities for the evolution of male to female sex change; the ability to change sex in both directions reduces the frequency of risky movement between host corals to form new pairs. These conditions are very similar to those reported in the both-ways sex change of another coral-dwelling goby Paragobiodon echinocephalus.  相似文献   
36.
We molecularly cloned JC polyomavirus DNAs from urine samples of eight nonimmunosuppressed patients and two healthy individuals. The cloned viral DNAs all contained an archetypal regulatory sequence from which various regulatory sequences of JC polyomavirus isolates derived from patients with progressive multifocal leukoencephalopathy could have evolved by deletion and amplification.  相似文献   
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The human polyomavirus BK virus (BKV) is ubiquitous in humans, infecting children asymptomatically. BKV is the only primate polyomavirus that has subtypes (I–IV) distinguishable by immunological reactivity. Nucleotide (nt) variations in a major capsid protein (VP1) gene region (designated the epitope region), probably responsible for antigenic diversity, have been used to classify BKV isolates into subtypes. Here, with all the protein-encoding gene sequences, we attempted to elucidate the evolutionary relationships among 28 BKV isolates belonging to subtypes I, III, and IV (no isolate belonging to subtype II, a minor one, was included). First, using the GTR + Γ + I model, maximum likelihood trees were reconstructed for individual viral genes as well as for concatenated viral genes. On the resultant trees, the 28 BKV isolates were consistently divided into three clades corresponding to subtypes I, III, and IV, although bootstrap probabilities are not always high. Then we used more sophisticated likelihood models, one of which takes account of codon structure, to elucidate the phylogenetic relationships among BKV subtypes, but the phylogeny of the deep branchings remained ambiguous. Furthermore, the possibility of positive selection in the evolution of BKV was examined using the nonsynonymous/synonymous rate ratio as a measure of selection. An analysis based on entire genes could not detect any strong evidence for positive selection, but that based on the epitope region identified a few sites potentially under positive selection (these sites were among those showing subtype linked polymorphisms). These author Yuriko Nishimoto and Tomokazu Takasaka contributed equally to this article. [Reviewing Editor: Dr. Rasmus Nielsen]  相似文献   
39.
JC polyomavirus (JCV), the causative agent of progressive multifocal leukoencephalopathy (PML), is ubiquitous in humans, infecting children asymptomatically and then persisting in the kidney. Renal JCV is not latent but replicates to excrete progeny in the urine. The renal-urinary JCV DNAs carry the archetype regulatory region that generates various rearranged regulatory regions occurring in JCVs derived from the brains of PML patients. Tissue cultures that support the efficient growth of archetype JCV have not been reported. We studied whether archetype JCV could replicate in COS-7 cells, simian cells transformed with an origin-defective mutant of simian virus 40 (SV40). Efficient JCV replication, as detected by a hemagglutination assay, was observed in cultures transfected with five of the six archetype DNAs. The progeny JCVs could be passaged to fresh COS-7 cells. However, when the parental cells of COS-7 not expressing T antigen were transfected with archetype JCV DNAs, no viral replication was detected, indicating that SV40 T antigen is essential for the growth of JCV in COS-7 cells. The archetype regulatory region was conserved during viral growth in COS-7 cells, although a small proportion of JCV DNAs underwent rearrangements outside the regulatory region. We then attempted to recover archetype JCV from urine by viral culture in COS-7 cells. Efficient JCV production was observed in COS-7 cells infected with five of the six JCV-positive urine samples examined. Thus, COS-7 cells should be of use not only for the production of archetype JCV on a large scale but also for the isolation of archetype JCV from urine.  相似文献   
40.
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