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Donor-specific transfusion (DST) is one of the methods to prevent allograft rejection, presumably through induction of donor-specific nonresponsiveness in humans and animal models. In this study, we used a skin graft model in fully allogeneic (AKR into B6), H-2 class I-disparate (bm1 into B6), class II-disparate (bm12 into B6), minor-H-disparate (C3H/SW into B6) and whole MHC-disparate (B10.BR into B10) combinations to analyze the mechanisms of DST-induced immunomodulation from the view point of antigen disparity. Skin graft survival was prolonged by DST only in the combination of bm1 and B6 as already confirmed by many reports. In other combinations, skin graft survivals were not prolonged at all by DST but rather shortened. In a fully allogeneic combination between AKR and B6 in which I-E antigens or Mls-1 antigens are recognized by T-cell subsets with TCR Vbeta11 or Vbeta6, respectively, responses to stimulation by anti-Vbeta11 and Vbeta6 monoclonal antibodies were decreased by DST. Furthermore, the number of Vbeta6+ T cells was decreased in the periphery probably due to peripheral clonal deletion. In such a condition, the mixed lymphocyte reactions of B6 to AKR were reduced to some extent, but were clearly detected. In addition, skin allografts from AKR were more rapidly rejected in B6 mice given AKR spleen cells. From these results, DST seems to induce nonresponsiveness to some antigens (I-E antigens, Mls antigens and bm1 antigens in this study), but not to others. Our study also indicated that DST alone, at least in the absence of other treatments, does not contribute to allograft tolerance in fully allogeneic combinations.

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Dermoid cysts are benign cystic teratomas lined by skin and epidermal appendages. We report a dermoid cyst occurring in a 26-year-old female whose chief complaint was irregular vaginal bleeding. Abdominal magnetic resonance image demonstrated a space-occupying lesion in the right lower abdomen. The mass showed hyperintensity on the T2 image and the signal was homogeneous for the interior. During abdominal surgery we made the diagnosis of subserous tumor of the colon and resected the ileocecal portion of the colon. The tumor measured 5.4 x 4.8 x 3.5 cm and was soft and elastic. On cross section, a unilocular cyst filled with atheromatous material was found. Pathological examination revealed a dermoid cyst. In the view of this diagnosis, a simple excision would have been an adequate treatment.

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A precancerous change has been identified incidentally in resected specimens from patients who have undergone cholecystectomy. We focused on chronic cholecystitis, showing a thick and sclerotic wall caused by recurrent inflammation, e.g. contracted cholecystitis, and examined the malignant potential of these lesions. We studied 88 patients who had undergone cholecystectomy. Contracted cholecystitis was diagnosed, using our criteria, in 28 of these cases. Ordinary chronic cholecystitis was diagnosed in 50 cases and gallbladder carcinoma in ten cases. We examined the expression of p53, Ki-67, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) immunohistochemically. Severe dysplasia or carcinoma in situ in a very small portion of the specimen was identified with hematoxylin-eosin staining in four cases (14.3%) of contracted cholecystitis. These specimens revealed a positive expression of not only p53, but also Ki-67, iNOS, and COX-2. Statistical significance was shown among the three disease groups in terms of the incidence of p53 overexpression, respectively (P<0.05). The results of this study suggest that contracted cholecystitis could be an early change leading to carcinogenesis.

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More than 60% of species examined from a total of 421 strains of heterotrophic marine bacteria which were isolated from marine sponges and seawater were observed to have no detectable siderophore production even when Fe(III) was present in the culture medium at a concentration of 1.0 pM. The growth of one such non-siderophore-producing strain, alpha proteobacterium V0210, was stimulated under iron-limited conditions with the addition of an isolated exogenous siderophore, N,N'-bis (2,3-dihydroxybenzoyl)-O-serylserine from a Vibrio sp. Growth was also stimulated by the addition of three exogenous siderophore extracts from siderophore-producing bacteria. Radioisotope studies using (59)Fe showed that the iron uptake ability of V0210 increased only with the addition of exogenous siderophores. Biosynthesis of a hydroxamate siderophore by V0210 was shown by paper electrophoresis and chemical assays for the detection of hydroxamates and catechols. An 85-kDa iron-regulated outer membrane protein was induced only under iron-limited conditions in the presence of exogenous siderophores. This is the first report of bacterial iron uptake through an induced siderophore in response to exogenous siderophores. Our results suggest that siderophores are necessary signaling compounds for growth and for iron uptake by some non-siderophore-producing marine bacteria under iron-limited conditions.

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Cell surface modification during mesenchyme ingression was examined using a monoclonal antibody (mAb), anti-Epith-1 mAb, raised against a protein (Epith-1) that was confined to the lateral surface of the epithelial cells in embryo of the sea urchin, Temnopleurus hardwicki. The mAb epitope was N-glycosylated oligosaccharides of 160 kDa monomeric Epith-1 protein. The glycoprotein was negatively charged, and its isoelectric point (IP) was 4.98. The mAb, however, is not immunologically cross-reactive with other sea urchin embryos including Hemicentrotus pulcherrimus, Strongylocentrotus nudus, and Scaphechinus mirabilis. Epith-1 is present initially in the cytoplasm of unfertilized eggs. Cytoplasmic Epith-1 shifted to the cell surface to be integrated in plasma membrane during the first cleavage, and remained there during early embryogenesis by retaining the same relative molecular mass (Mr). During primary and secondary mesenchyme ingression periods, however, Epith-1 disappears from the presumptive mesenchyme cell surface that was associated with internalization of the protein. In plutei, an additional anti-Epith-1 mAb-positive protein appears at the 142 kDa region, which was not associated with any visible alteration of the histologic localization of the protein in larvae. Anti-Epith-1 mAb IgG did not inhibit the reaggregation of epithelial cells in vitro, which suggests that either the protein is not involved in cell-cell adhesion or that the mAb is not recognizing the active site of the protein.

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We report an extremely rare case of a splenic epidermoid cyst of the pancreas in a 51-year-old Japanese male with no clinical symptoms. A cystic tumor of the pancreatic tail was detected incidentally by abdominal ultrasonography. The patient was referred to the Gunma University Hospital for further examination of the pancreatic tumor. Upon diagnosis of a benign cystic tumor, a distal pancreatectomy with splenectomy was performed. Microscopically, the multicystic tumor, which was surrounded by the splenic tissue, was located within the pancreatic tissue. The cysts were lined by non-keratinizing squamous epithelium. The diagnosis of an epidermoid cyst occurring in an intrapancreatic accessory spleen was confirmed. To our knowledge, this is the 4th case ever reported in the English literature.

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In the present study it was found that serotonergic apical ganglion (SAG)-forming cells in plutei of the sea urchin, Hemicentrotus pulcherrimus, possessed a characteristic pear shape with broad apical sides and a pointed basal side in the acron epithelium. The basal side extended axons through the space between the epithelium and the basal lamina toward the midline of the embryo that aligned parallel to the embryonic anteroposterior axis. Serotonergic apical ganglion-forming cells had epithelial cell surface-specific proteins on their entire surface. The SAG in 4-arm plutei was composed of a 4-cell trunk region that aligned at right angles to the embryonic anteroposterior axis, and forked into two branches of one to two cells at both ends. Two branches extended toward the oral and the other two toward the aboral region, respectively. Double-stained immunohistochemistry using antiserotonin antibodies and oral ectoderm-specific anti-Ecto V monoclonal antibody or aboral ectoderm-specific anti-Ars antibodies indicated that SAG was in the aboral ectoderm region. Serotonergic apical ganglion cells were first detected in late gastrulae and increased in number rapidly between 36 and 48 h after fertilization, and then slowly afterwards. A 5-bromo-2-deoxyuridine incorporation study indicated that none of the increased SAG cells were in the S phase during the aforementioned period, suggesting that SAG cells do not proliferate by cell division, but acquire the property in particular cells by transdifferentiation using a mechanism that has yet to be elucidated.

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X-ray crystallographic analysis was performed and several phenylahistin derivatives were synthesized to elucidate the structural components necessary for the anti-microtubule activity of phenylahistin. We primarily focused on the unique isoprenylated dehydrohistidine structure. Our results showed that a uniplanar pseudo-three-ring structure formed by the hydrogen bonding of diketopiperazine and imidazole rings is important for the anti-microtubule activity of phenylahistin.

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Phenylahistin is a new cell cycle inhibitor produced by Aspergillus ustus. Since phenylahistin was produced as a scalemic mixture of (-)-phenylahistin and its enantiomer, we separated each enantiomer and evaluated their antitumor activity in vitro. (-)-Phenylahistin exhibited antitumor activity against 8 tumor cell lines with IC50 values ranging from 1.8 x 10(-7) to 3.7 x 10(-6), while (+)-phenylahistin exhibited 33-100-fold less potent activity than (-)-phenylahistin did. (-)-Phenylahistin also showed antitumor activity against P388 leukemia and Lewis lung carcinoma cells in vivo.

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(-)-Phenylahistin, a fungal diketopiperazine metabolite composed of phenylalanine and isoprenylated dehydrohistidine, arrested cells in mitosis and inhibited the proliferation of A549 cells. The microtubule network in A549 cells was disrupted by (-)-phenylahistin, which also inhibited the polymerization of both microtubule protein from bovine brain and phosphocellulose-purified tubulin in vitro. Competitive binding studies indicated that (-)-phenylahistin interacted with the colchicine binding site on tubulin but not with the vinblastine binding site.

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To study the effect of inserted peptides on the secretion and processing of exported proteins in Bacillus subtilis and Escherichia coli, pBR322-derived DNA fragments coding for small peptides were inserted between the DNA coding for the 31 amino acid B. subtilis alpha-amylase signal peptide and that coding for the mature part of the extracellular thermostable alpha-amylase of B. stearothermophilus. Most of the inserted peptides (21 to 65 amino acids) decreased the production of the enzyme in B. subtilis and E. coli, the effect of each peptide being similar in the two strains. In contrast, with one peptide (a 21 amino acid sequence encoded by the extra DNA in pTUBE638), the production of alpha-amylase was enhanced more than 1.7-fold in B. subtilis in comparison with that of the parent strain. The molecular masses of the thermostable alpha-amylases in the periplasm of the E. coli transformants varied for each peptide insert, whereas those in the culture supernatants of the B. subtilis transformants had molecular masses similar to that of the mature enzyme. Based on the NH2-terminal amino acid sequence of the hybrid protein from pTUBE638, it was shown that in E. coli, the NH2-terminally extended thermostable alpha-amylase was translocated and remained in the periplasm after the 31 amino acid signal sequence was removed. In the case of B. subtilis, after the removal of a 34-amino acid signal sequence, the hybrid protein was secreted and processed to the mature form.

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Lung studies with N-Isopropyl-I-123-p-Iodoamphetamine (IMP) were performed on patients with lung cancer or inflammatory disease. In the present study, we evaluated the usefulness of the delayed scintigraphy. The subjects consisted of 27 patients with lung cancer (34 lesions), 3 with radiation pneumonitis, 2 with interstitial pneumonitis, 2 with old tuberculous lesion (tuberculomas), 1 with diffuse panbronchiolitis, 1 with pneumonia and 1 with lung abscess. The delayed scintigraphy was performed 24 hr after intravenous injection of 3 mCi IMP, in sitting position. In 10 patients, SPECT images were obtained following the delayed scintigraphy. Delayed scintigraphic appearances of lung cancer were classified into 5 types, high IMP uptake in the area congruent with the lesion of atelectasis and/or obstructive pneumonia (Type I), high IMP uptake in the area surrounded the tumor (Type II), a defect in the area consistent with the tumor and no high IMP uptake in the area surrounded the tumor (Type III), high IMP uptake in the area almost congruent with the tumor (Type IV) and no significant change (Type V). Excluding 10 lesions with Type IV or V, no IMP uptake was seen in the areas congruent with the tumors. Type II was the most frequently observed pattern. Normal scintigrams (Type V) were observed in 8 lesions, whose sizes were fairly small. There was no definite trend caused by difference in histological types of cancers. In 8 patients with viable inflammatory disease of the lung, the delayed scintigrams showed high IMP uptake in the areas congruent with the abnormalities on chest roentgenograms.(ABSTRACT TRUNCATED AT 250 WORDS)

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