Characterisation of an anti-ulcer pectic polysaccharide from leaves of Panax ginseng C.A. Meyer

Structural characterisation of an anti-ulcer polysaccharide (GL-BIII), purified from leaves of Panax ginseng C.A. Meyer, was studied. Methylation analysis indicated that GL-BIII consisted mainly of terminal Arap, 4- or 5-substituted Ara, 2,4-disubstituted Rha, 4- and 6-substituted Gal, and 3,6-disubstituted Gal. Single radial gel diffusion using beta-glucosyl-Yariv antigen indicated that GL-BIII contained a small proportion of a beta-(1-->3,6)-galactan moiety. GL-BIII also contained terminal, 4-substituted, and 3,4-disubstituted GalA, and terminal and 4-substituted GlcA. Base-catalysed beta-elimination suggested that some 2-substituted Rha in GL-BIII was attached to position 4 of a 4-substituted uronic acid. Both mild acid hydrolysis and endo-alpha-(1-->4)-polygalacturonase digestion of GL-BIII did not give fragments consisting mainly of GalA. Methylation analysis and GC-MS analysis of acidic oligosaccharides liberated by partial acid hydrolysis indicated that GL-BIII contained a GalA-(1-->4)-Rha unit in addition to longer acidic units consisting of 2-substituted Rha and 4-substituted GalA. Lithium-mediated degradation of GL-BIII followed by borohydride reduction gave small amounts of fractions containing long and intermediate neutral oligosaccharide-alditols and a large amount of a fraction containing short oligosaccharide-alditols. The long neutral oligosaccharide-alditol fraction mainly comprised 4- or 5-substituted Ara, terminal Galf, 6-substituted Glc, and 2-substituted Man, whereas the intermediate oligosaccharide-alditol fraction consisted mainly of terminal and 6-substituted Galp, 6-substituted Glc, and 2-substituted Man. Methylation analysis and GC-MS analysis of the short oligosaccharide-alditol fraction suggested that it contained at least 14 kinds of di- to tetra-saccharide-alditols such as Gal-(1-->2)-Rha-ol, Gal-(1-->4)-Rha-ol, Ara-->Ara-ol, and Ara-->Ara-->Ara-ol.

Existence of a rhamnogalacturonan II-like region in bioactive pectins from medicinal herbs

Unusual component sugars such as 2-methylfucose (2-Me-Fuc), 2-methylxylose (2-Me-Xyl), apiose (Api), and aceric acid (AceA) are contained in the bioactive pectins from Bupleurum falcatum, Glycyrrhiza uralensis, and Angelica acutiloba, but not in the other bioactive pectic heteroglycans and arabinogalactans from Chinese and Japanese herbs tested. Each pectin was digested with endo-alpha-(1-->4)-polygalacturonase, and gave two enzyme-resistant fractions, PG-1 (rhamnogalacturonan core with neutral sugar side-chains) and PG-2, and an oligogalacturonide fraction (PG-3) by gel filtration on Bio-gel P-30. The PG-2 fractions commonly consisted of unusual sugars such as 2-Me-Fuc, 2-Me-Xyl, Api, AceA, 3-deoxy-D-lyxo-heptulosaric acid (Dha), and 3-deoxy-D-manno-2-octulosonic acid (Kdo) in addition to Rha, Fuc, Ara, Xyl, Man, Gal, Glc, GalA, and GlcA. Lithium degradation of each PG-2 gave a pentosyl-->6-deoxyhexosyl-->6-deoxyhexosyl-->pentitol fragment as a major oligosaccharide in addition to some neutral di- to trisaccharide alditols. Methylation analysis of the lithium degradation products from each PG-2 also indicated that these oligosaccharide alditols mainly consisted of terminal Rha, Araf, Fuc, Xyl, and Gal, 4-linked Rha, 3-linked Fuc, and 3'-linked Api. HPLC analysis showed that PG-2 had molecular heterogeneity. These results indicate that the bioactive pectins from medicinal herbs commonly consist of the minor KDO-containing region which resembles the rhamnogalacturonan II in plant cell walls.

Polyclonal antibody against a complement-activating pectin from the roots of Angelica acutiloba

Anti-sera against a complement-activating pectin (AR-2IIb), which was purified from the roots of Angelica acutiloba Kitagawa, were obtained by immunization of rabbits, and a polyclonal anti-AR-2IIb antibody of the IgG class was purified by affinity chromatography on AR-2IIb-immobilized Sepharose and Protein G-Sepharose. Periodate oxidation of AR-2IIb significantly reduced its inhibitory activity on the reactivity of AR-2IIb to anti-AR-2IIb-IgG, but pronase digestion of AR-2IIb did not affect its inhibitory activity. Other pharmacologically active pectins from A. autiloba, Bupleurum falcatum, and Glycyrrhiza uralensis and the complement-activating pectic arabinogalactan from A. autiloba also showed significant inhibitory activities on the reactivity of AR-2IIb to anti-AR-2IIb-IgG, but these inhibitory activities were lower than that of AR-2IIb. Other pectins, polygalacturonic acid, arabinogalactan, galactan, and araban tested had negligible inhibitory activity. Endo-a-(1-->4)-polygalacturonase digestion of AR-2IIb indicated that its "ramified" region (rhamnogalacturonan core possessing neutral oligosaccharide side-chains) contained epitopes for anti-AR-2IIb-IgG, but that 2-keto-3-deoxyoctulosonic acid (KDO)-containing regions and oligogalacturonides obtained from AR-2IIb were not recognized by anti-AR-2IIb-IgG. Although carboxyl-reduction of galacturonic acid in the "ramified" region decreased the inhibitory activity of the "ramified" on its reactivity to anti-AR-2IIb, an acidic tetrasaccharide unit in the rhamnogalacturonan core had negligible inhibitory activity.

Interference between normal vibrato and artificial stimulation of laryngeal muscles at near-vibrato rates

A stabilized tremor hypothesis for vocal vibrato is investigated. The stabilizer is assumed to be a mechanical oscillator that may contain reflex loops. Artificial stimulation of the cricothyroid muscle in one subject showed a well-defined resonance curve of this peripheral oscillator at approximately 5.0 Hz. Combined artificial stimulation with natural vibrato showed that the vibrato could be entrained by a peripheral stimulus, provided the two frequencies are separated by no more than approximately +/- 0.5 Hz. This suggests that vibrato frequencies are not "hard-wired" centrally, even though a collection of centrally generated tremors may serve as excitation to the peripheral oscillator.

Severe rhabdomyolysis as a complication of peripheral blood stem cell transplantation

We present a case of severe rhabdomyolysis developing after peripheral blood stem cell transplantation (PBSCT) in a 17-year-old woman with Ki-1 lymphoma. Severe muscle weakness, myoglobinemia and acute renal failure developed on day 23 following PBSCT associated with painful peripheral neuropathy. Cytomegalovirus infection may have been a contributory factor.

Cerebral hyperemia in MELAS

BACKGROUND

The pathophysiology of stroke-like episodes in MELAS (mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes) is uncertain.

CASE DESCRIPTION

We studied a 24-year-old man with MELAS who had fluent aphasia and right hemianopia. Magnetic resonance imaging and computed tomography showed a large infarction in the parietal, temporal, and occipital lobes. We performed serial planar 133Xe regional cerebral blood flow studies and single-photon emission computed tomography. Fifteen and 26 days after the stroke-like episode, there was generalized hyperperfusion, highest in infarcted areas. Four and 8 months after the stroke-like episode, the brain was still hyperemic, with highest flow in noninfarcted tissue. Reactivity to CO2 was less than normal within the infarct at 26 days but improved thereafter. In the noninfarcted region, vasomotor reactivity was impared at 4 months, when resting flows were at their peak.

CONCLUSIONS

We observed generalized cerebral hyperemia and fluctuating CO2 reactivity in MELAS, possibly a consequence of local lactic acid production. In addition, this case suggests that nonquantitative functional imaging may be misleading in MELAS.

Expression of P-glycoprotein in de novo acute myelogenous leukemia at initial diagnosis: results of molecular and functional assays, and correlation with treatment outcome

We investigated the expression of P-glycoprotein (P-gp) in 52 adults with de novo acute myelogenous leukemia (AML) at the initial diagnosis. We tested 52 patients by flow cytometry using the MRK16 monoclonal antibody (MoAb). To investigate the phenotype for multidrug resistance, 41 of the patients were analyzed using rhodamine 123 (Rh123). We found that 14 (27%) of the 52 patients were positive for P-gp expression by MRK16 MoAb using a cutoff of 5% positive cells. There was a significant correlation between the results of the two analyses (p < 0.01). We suggest that flow cytometry using MRK16 MoAb is acceptable for use in detecting P-gp expression in clinical samples. Among the 52 patients, 43 (83%) obtained a complete remission (CR) and 45% of remitters were predicted to be alive and in a CR after 8 years. Although the rate of CR on the MRK16-positive patients was comparable to that of the MRK16-negative patients, the MRK16-positive patients were prone to relapse. We conclude that determination of P-gp expression of de novo AML at initial presentation did not significantly influence the outcome of treatment.

Teleocidins and benzolactams inhibit cell killing by human immunodeficiency virus type 1 (HIV-1)

Teleocidin B-4 and structurally related synthetic benzolactams were found to be potent inhibitors of cell killing by HIV-1. One of the benzolactams, (-)-BL-V8-310, showed a high selectivity index.

[Imaging and clinical significance of hepatic portal venous gas seen in adult patients]

In 10 adult patients with hepatic portal venous gas (HPVG), the clinical significance of HPVG and the efficacy of X-ray computed tomography (CT) were evaluated. HPVG was associated with ischemic bowel disease (n = 3), trauma (n = 4), liver abscess (n = 1), sepsis (n = 1), and unknown etiology (n = 1). The diagnostic ability of CT for the detection of HPVG was far superior to that of plain abdominal radiograph. Of 9 patients who underwent CT, HPVG located in the left hepatic lobe in all patients, and also in right hepatic lobe in 7 patients. Gas could be recognized in the left lobe and the anterior segment of the right lobe more clearly than in the posterior segment of the right lobe because of its larger amount of intravenous collection. The mortality rate of our cases was 100%. Gas was demonstrated simultaneously in the portal vein radicles and hepatic veins on CT in 4 patients with no clinical evidence of sepsis, which suggested the possibility of intraparenchymal shift of gas from the portal vein into the hepatic vein. In a single case with sepsis, gas was noted in various vessels, including arteries, in addition to the portal venous system. The authors conclude that HPVG is still a grave sign in Japan and prompt appropriate treatment is required. CT may be of great value in the early detection of HPVG and may indicate its etiology.

A retrospective study of 66 esophageal reconstructions using microvascular anastomoses: problems and our methods for atypical cases

We have studied 66 patients who underwent esophageal reconstruction using microvascular anastomoses. This series comprises 28 patients with reconstruction using a free jejunal interposition between the pharynx and the cervical esophagus following pharyngolaryngoesophagectomy for hypopharyngeal carcinoma and 38 atypical patients in whom other methods of reconstruction were used. Successful transfer was achieved in 98.5 percent (65 of 66). Issues concerning atypical reconstruction and our procedures in these cases are discussed. In order to obtain adequate tension in the jejunum on the anal side, in particular, since the anastomosis is located in a deep or narrow space, autosuture instruments were used. The anastomotic leakage rate was 2.8 percent (1 of 36); the stenosis rate was 2.8 percent (1 of 36). To prevent necrosis in the trachea, a greater omentum flap was used in three patients, a mesenterium flap in two, and a pectoralis major musculocutaneous flap in one. There were no significant complications. In patients with a short gastric pedicle or in those in whom a double cancer occurred in the hypopharynx and thoracic esophagus, a gastric pedicle and a free jejunum flap were used together. As a result of this method, the incidence of any reflux of digestive juice was reduced to 0 percent (0 of 6). To reduce the possibility of an ischemic complication at the oral end of the colonic pedicle, we added a microvascular anastomosis of the colonic pedicle, thereby reducing both leakage [0 percent (0 of 9)] and necrosis [0 percent (0 of 9)]. These procedures involving microvascular anastomoses have reduced the incidence of complications in esophageal reconstructions.

Lipopolysaccharide-independent limulus amebocyte lysate activating, mitogenic and anti-complementary activities of pectic polysaccharides from chinese herbs

Bioactive pectic polysaccharides from Chinese herbs were tested for the presence of lipopolysaccharide (LPS) or LPS-like substances by chromogenic Limulus amebocyte lysate (LAL)-assay. Pectic polysaccharides from BUPLEURUM FALCATUM, GLYCYRRIZA URALENSIS, and ANGELICA ACUTILOBA were LAL-positive at different rates. The fractions GR-2IIc/PG-1 (ramified region; rhamnogalacturonan core with neutral sugar side chains) from G. URALENSIS and AGIIb-1 (acidic arabinogalactan) from A. ACUTILOBA activated the endotoxin-mediated coagulation factor (factor C). When the pectin-like polysaccharide bupleuran 2IIc from B. FALCATUM was digested with ENDO-polygalacturonase or degraded with lithium, the resulting oligosaccharides still showed LAL-reactivity. Carboxyl-reduction of acidic polysaccharides increased the reactivity to the beta(1-->3)-glucan-mediated coagulation factor (factor G) but not the factor C. Bupleuran 2IIc and its PG-1 and PG-2 (rhamnogalacturonan II-like region, which contains 2-keto-3-deoxyocuturosonic acid) showed significant mitogenic activities even by using C3H/HeJ mice which are low responder mice to LPS. When the LAL-positive substance was removed from bupleuran 2IIc and its fraction PG-1 by phase separation using Triton X-114, the mitogenic and anti-complementary activities did not change. These results indicated that mitogenic and anti-complementary activity of bioactive pectic polysaccharides from B. FALCATUM were due to the action of pectic polysaccharides but not LPS.

Mitochondrial encephalomyopathies: clinical and molecular analysis

The classification of mitochondrial encephalomyopathies relied upon clinical, biochemical, and histological features until the discovery of mitochondrial DNA defects in 1988. Since then, an outburst of molecular genetic information has aided our understanding of the pathogenesis and the classification of these heterogeneous disorders. Novel concepts of maternal inheritance, mitochondrial DNA (mtDNA) heteroplasmy, tissue distribution, and threshold have explained many of the clinical characteristics. The discovery of point mutations, large-scale mtDNA deletions, duplications, and autosomally inherited disorders with multiple mtDNA deletions have revealed new genetic phenomena. Despite our rapidly expanding understanding of the molecular genetic defects, many questions remain to be explored to fill the gap in our knowledge of the relationship between genotype and clinical phenotype.

Translocation (3;21)(q26;q22) in treatment-related acute leukemia secondary to acute promyelocytic leukemia

We performed cytogenetic studies in a patient with treatment-related acute leukemia (t-AL) to identify the associated chromosomal changes. Metaphase analysis revealed a t(3;21)(q26;q22) translocation. Acute promyelocytic leukemia (APL) had been diagnosed 4 years earlier and the patient had received intensive induction chemotherapy and sequential post-induction therapy that included agents that targeted DNA-topoisomerase II (topo II). This case suggests an association between previous therapy with topo II inhibitors and development of t-AL associated with a balanced aberration involving the 3q26 and 21q22 bands.

Acoustic analysis of functional dysphonia: before and after voice therapy (accent method)

Ten patients who were referred to a speech pathologist for functional voice disorders were treated with voice therapy using the accent method. The vocal folds were normal except in three females who had moderate bilateral nodules. The voices were analyzed acoustically before and after treatment. Of the parameters tested, pitch perturbation quotient, amplitude perturbation quotient, normalized noise energy for 1-4 kHz, and fundamental frequency showed significant improvement.

[A study of biological characteristics of large bowel adenocarcinomas showing mucin production; examination of histological differentiation and cell kinetics]

In order to clarify the biological behavior of mucin producing cancers of colon, we analyzed 32 cases showing histological heterogeneity in the tumors, by mucin histochemistry. 28 cases were mucinous adenocarcinoma, forming with tubular structures, and the remaining 4 cases were signet-ring cell carcinomas. HID-AB stain demonstrated that the mucin component was almost similar to that of normal mucosa around the cancer. In the tubular forming portions, in which polyploid or aneuploid cells were often detected, the growth fraction of cancers was significantly higher than in that of the other portions.

Mitochondrial DNA mutations in an outbreak of optic neuropathy in Cuba

Since October 1991, nearly 51,000 Cubans have been afflicted in an outbreak of optic and peripheral neuropathies. To begin an investigation of the possible role of mitochondrial DNA (mtDNA) mutations in the outbreak, we studied mtDNA from 14 affected and two unaffected Cubans for the 12 mutations associated with Leber's hereditary optic neuropathy. Eleven probands (12 patients) had optic neuropathy and two had peripheral neuropathy only. We also studied two unaffected relatives of one proband. We identified two mtDNA mutations, at nucleotides 11778 and 3460, in two of the 11 probands with optic neuropathy. Although this data set is too small to reach statistically valid conclusions, it does suggest that mtDNA mutations might be contributing to the outbreak of optic neuropathy in Cuba.

Some aspects of vocal fold bowing

Bowing of the vocal fold frequently occurs in patients with vocal fold paralysis (VFP), those with sulcus vocalis, and those who have had laser surgery. Additionally, there are vocal folds that present bowing with no noticeable organic lesion. For the purpose of investigating the causes and mechanisms of vocal fold bowing, consecutive fiberscopic videorecordings of 127 patients with VFP, 33 with sulcus vocalis, 33 with laser surgery, and 33 with dysphonia having no clinically noticeable organic lesion were reviewed. Sixty-nine percent of the paralyzed vocal folds had bowing, and the occurrence of bowing was significantly related to the activity of the thyroarytenoid muscle as measured by electromyography. The cricothyroid activity had no significant relationship to vocal fold bowing. All vocal folds with sulcus presented with bowing. Thirty-five percent of the vocal folds that had had laser surgery had bowing. The extent of tissue removal was closely related to the occurrence of bowing. Twelve cases with no organic lesion had vocal fold bowing. Of these 12 patients, 8 were male and 9 were older than 60 years. Some aging process in the mucosa was presumed to be the cause of the bowing in this age group of patients without clinically noticeable organic lesions. Causes of vocal fold bowing in the younger group of patients without organic lesions were not determined in this study.

[The influence of subclinical level of graft versus host reaction on reconstitution of host lymphoid tissues]

In this study reconstitution of lymphoid tissues under the influence of subclinical graft versus host reaction (GVHR) was investigated. Lethally irradiated recipient mice (AKR: H-2k, Mls-1a) were reconstituted with donor (B10: H-2b, Mls-1b) bone marrow (BM) cells treated with anti-Thy 1 antibody alone without complement (GVHR chimeras). When their immunological reconstitution was analysed and compared with that of AKR recipients which had been reconstituted with B10 BM treated with anti-Thy 1 and complement (Control chimera), both of these chimeras all survived more than 100 days without showing clinical signs of GVHD. Full donor chimerism was accomplished at an early stage after BM transplantation (BMT) in GVHR chimeras, whereas substantial number of recipient T cells persisted in Control chimeras during the entire observation period. No significant difference was observed in the reconstitution of the thymus and spleen between the Control and GVHR chimeras. By contrast, the reconstitution of lymph nodes (LN) in GVHR chimeras was inhibited. The apparent failure of LN reconstitution was attributed to damage of LN structure involved in homing of lymphocytes, but not attributable to damage of lymphocytes themselves. Since donor CD8+ T cells caused the damage, target antigens of this damage appeared to be H-2 class I molecules in the present system. Furthermore, clonal deletion of V beta 6+T cells that are reactive to recipient Mls-1a antigen was induced in Control chimeras but abrogated in the GVHR chimeras. The latter abrogation of clonal deletion of V beta 6+T cells appeared to result from the early disappearance of recipient T cells in these GVHR chimeras.

Histological and microradiographic evaluation of hydrated and hardened alpha-tricalcium phosphate/calcium phosphate dibasic mixtures

Bone tissue response to pre-hardened alpha-tricalcium phosphate (alpha-TCP) and calcium phosphate dibasic (DCPD) mixture by hydration was studied histologically and microradiographically after implanting on the inferior aspect of the mandible in rabbits. In 1-month implants, new bone formation was observed along the surface of the material near the host bone, and connection of new and host bone through thin bone bridges was seen in some places. In 3-month implants, newly formed bone filled the greater part of the gap between material and host bone, and in 6-month implants, it surrounded almost all the surface of the material. New bone was in direct contact with the material in all implant periods. The bone response was essentially consistent with that to hydroxyapatite (HA). Resorption of the material was noticed in 3- and 6-month implants. It was concluded that pre-hardened alpha-TCP/DCPD mixture has good biocompatibility with bone tissue equal to HA and that it resorbs when implanted in rabbit. Further research should be performed to evaluate the material changes of resorption and formation of the white zone.

Mitochondrial neurogastrointestinal encephalomyopathy (MNGIE): clinical, biochemical, and genetic features of an autosomal recessive mitochondrial disorder

We studied the clinical, biochemical, and genetic features of eight patients with the autosomal recessive mitochondrial syndrome mitochondrial neurogastrointestinal encephalomyopathy (MNGIE). MNGIE is clinically characterized by ophthalmoparesis, peripheral neuropathy, leukoencephalopathy, gastrointestinal symptoms (recurrent nausea, vomiting, or diarrhea) with intestinal dysmotility, and histologically abnormal mitochondria in muscle. Brain MRI scans were consistent with leukodystrophy in seven patients examined. Nerve conduction and EMG studies were compatible with a sensorimotor neuropathy; quantitative EMG of two patients suggested a myogenic process. Muscle mitochondrial enzyme analysis revealed a partial defect of cytochrome c oxidase activity in five patients; three had additional respiratory chain enzyme defects. Two patients had isolated complex I defects, and one had normal respiratory chain function. Southern blot analysis revealed multiple deletions of mitochondrial DNA in four of eight patients.

The interaction of small domains between the subunits of phosphatidylinositol 3-kinase determines enzyme activity

Previous studies have suggested that the two subunits of phosphatidylinositol (PI) 3-kinase, p85 and p110, function as localizing and catalytic subunits, respectively. Using recombinant p85 and p110 molecules, we have reconstituted the specific interaction between the two subunits of mouse PI 3-kinase in cells and in vitro. We have previously shown that the region between the two Src homology 2 (SH2) domains of p85 is able to form a functional complex with the 110-kDa subunit in vivo. In this report, we identify the corresponding domain in p110 which directs the binding to p85. We demonstrate that the interactive domains in p85 and p110 are less than 103 and 124 amino acids, respectively, in size. We also show that the association of p85 and p110 mediated by these domains is critical for PI 3-kinase activity. Surprisingly, a complex between a 102-amino-acid segment of p85 and the full-length p110 molecule is catalytically active, whereas p110 alone has no activity. In addition to the catalytic domain in the carboxy-terminal region, 123 amino acids at the amino terminus of p110 were required for catalytic activity and were sufficient for the interaction with p85. These results indicate that the 85-kDa subunit, previously thought to have only a linking role in localizing the p110 catalytic subunit, is an important component of the catalytic complex.