Possible relationship between poly(ADP-ribose)synthetase and formation of antibody against acetylcholine receptors in patients with myasthenia gravis

We examined the relationship of the serum levels of antibody against acetylcholine receptors to the serum levels of 13 enzymes, including various hydrolytic enzymes, poly(ADP-ribose)synthetase (Poly(ADP-ribose)Syn), and sialyltransferase (NANA-trans), in patients with myasthenia gravis. The patients were divided into two groups, depending on the presence or absence of thymoma. In spite of the absence of significant difference in the absolute levels of individual enzymatic activities between the two groups, the network relationships of such enzymes were quite different between the two groups. Of the 13 enzymes examined, only Poly(ADP-ribose)Syn showed a weak but significant correlation with the level of the antibody in the patients without thymoma. A multivariate study more clearly suggested the relationship between the antibody formation and Poly(ADP-ribose)Syn in the patients without thymoma. Such observations were not found in the patients with thymoma.     

Cloning and expression of a functional fucose-specific lectin from an orange peel mushroom, Aleuria aurantia

Aleuria aurantia lectin (AAL) shows sugar-binding specificity for L-fucose. A λgt11 expression library was constructed from A. aurantia poly(A) RNA and screened with a polyclonal antiserum directed against AAL. An immunopositive clone carrying 1.3-kb EcoRI fragment was obtained. The fragment encoded AAL, but lacked a nucleotide sequence corresponding to the two amino-terminal amino acids. The 5′-terminal part of the fragment was replaced with a chemically synthesized DNA fragment and inserted into an expression vector to yield a plasmid pKA-1. Escherichia coli carrying pKA-1 expressed functional AAL and the recombinant AAL showed the same immunological properties as those of natural AAL.     

Immunohistochemical localization of proteoglycans in interstitial elements of human pancreas and biliary system

Summary The immunohistochemical localization of large proteoglycan and small proteoglycan was observed, using antibodies 2B1 and 6B6 (Sobueet al., 1988, 1989a), in fetal and adult pancreas and biliary system as well as in tumour tissues, obtained from 11 autopsies and 74 biopsies. The distribution of chondroitin 4- and 6-sulphate side chains, type I and IV collagen and elastin were also studied. In adult pancreas and all the biliary tracts examined, periductal fibrous tissues consisted mainly of dermatan sulphate small proteoglycan with networks of fibrous elements, which were composed of large proteoglycan, elastin, type I collagen and type IV collagen. In the interstitial components of cystadenoma of pancreas and biliary duct carcinoma, similar small proteoglycan-rich components were relatively abundant, although large proteoglycan was present in much larger amounts than that in non-neoplastic adult tissues. In some cholangiomas, the extra-and intracellular hyaline globules formed by the carcinoma cells were found to contain chondroitin sulphate large proteoglycan, laminin and fibronectin.The distribution of proteoglycans was observed to be different in the arterial walls of the interlobular tissues of the adult and the fetal pancreas. The biological significance of large and small proteoglycans in the interstitial connective tissues was discussed.     

Three main components in plasma proteases and their relation to the renin-angiotensin system

The relation of plasma renin activity (PRA) and plasma levels of angiotensin I (AI) and II (AII) to those of various proteases, including eight endopeptidases and four aminopeptidases, was investigated in 51 normal control subjects. The multivariate study using factor analysis showed that the plasma proteases can be classified into three main components: the aminopeptidase, the plasmin, and the kinin-kallikrein. PRA and AI were related almost exclusively to the aminopeptidase component, while the AII level was related not only to the same component but also to the kallikrein-kinin component. This kind of multivariate study may help in the elucidation of the role of proteases and bioactive peptides, such as angiotensin derivatives, in essential hypertension through a comparison of multivariate relationships in controls and patients.     

Successful treatment for perinephric abscess with recombinant human granulocyte colony-stimulating factor following nephrectomy in a patient of myelodysplastic syndrome: A case report

The 35-year-old man with myelodysplastic syndrome (MDS) and granulocytopenia with dry cough and high fever was eventually found to have a left perinephric abscess ofStaphylococcus aureus. He underwent left nephrectomy and drainage of perinephric space in conjunction with appropriate antibiotics. However, because of persistent granulocytopenia,Staph. aureus never cleared up with formation of only poor granulation. Recombinant human granulocyte colony-stimulating factor (G-CSF) was added to the above treatment leading to prompt improvement in granulocytopenia and emergence of the good granulation tissue. G-CSF will probably become one of the important agents in treating MDS with granulocytopenia.     

Further study of effects of synthetic peptides on identifiable giant neurones of an African giant snail (Achatina fulica Férussac)

1. Effects of the following peptides at 10(-4) M on identifiable giant neurones of Achatina fulica Férussac were examined: physalaemin, eledoisin, bradykinin, neurokinin A, neurokinin B, neuromedin B, gastrin releasing peptide decapeptide (neuromedin C), gastrin releasing peptide (14-27), cholecystokinin tetrapeptide, cholecystokinin octapeptide, thyrotropin releasing hormone, Arg-vasotocin, gamma-melanocyte stimulating hormone. 2. The six neurones tested were as follows: PON (periodically oscillating neurone), TAN (tonically autoactive neurone), RAPN (right anterior pallial neurone), d-RPLN (dorsal-right parietal large neurone), VIN (visceral intermittently firing neurone) and d-VLN (dorsal-visceral large neurone). 3. Of the peptides examined, only Arg-vasotocin at 10(-4) M produced the excitatory effects on PON, VIN and d-VLN. Physalaemin showed slight inhibitory effects on TAN; this substance was sometimes almost ineffective on the neurone. 4. The other peptides examined were completely ineffective on all of the neurones tested.     

Somatomedin-C in the kidney of streptozotocin diabetic rats

To evaluate the possible role of somatomedin-C, insulin-like growth factor I, in renal hypertrophy in early diabetes, kidney tissue SmC concentrations were measured in streptozotocin-induced (80 mg/kg ip) diabetic rats. Body weight, liver weight, plasma SmC concentration, and SmC concentration in the liver of diabetic rats were significantly lower than those of controls. Seven days after induction of diabetes, the kidney weight (898 +/- 95 mg) in diabetic rats was significantly greater than that in controls (755 +/- 69 mg), while SmC concentration in the kidney of diabetic rats (1.7 +/- 0.3 U/g kidney) was significantly lower than that of control rats (5.4 +/- 0.6 U/g kidney). These results suggest that renal SmC may not have an important role in renal hypertrophy in early stages of diabetes and that renal production of SmC may be impaired by insulin deficiency in rats.     

Host range mutant of human immunodeficiency virus type 1: modification of cell tropism by a single point mutation at the neutralization epitope in the env gene.

We have isolated a variant of human immunodeficiency virus type 1 (HIV-1) which is highly infectious to fibroblastlike cells (BT cells) derived from human brain as well as CD4-positive T cells. This variant HIV-1, named HIV[GUN-1V], was obtained by infecting BT cells with a prototype HIV-1 isolate, named HIV[GUN-1WT], which is highly infectious to T cells but barely infectious to BT cells. HIV[GUN-1V] infects BT cells productively and this infection appeared to be mediated by CD4. To elucidate the viral gene responsible for the host range difference between the variant and prototype HIV-1s, we cloned and analyzed the provirus genomes of the two viruses. Examination of the infectivities of BT cells by various recombinant viruses and analyses of the nucleotide sequences of HIV[GUN-1V] and HIV[GUN-1WT] showed that a single nucleotide exchange was responsible for their difference in infectivity of BT cells: HIV[GUN-1V] contains a thymine residue instead of the cytosine residue in HIV[GUN-1WT] at position 931 of the env coding sequence. Replacement of cytosine by thymine at this position of the env coding sequence of the HIV[GUN-1WT] genome induced the ability to infect BT cells. The base exchange at this position was expected to change amino acid 311 of the envelope glycoprotein, gp120, from proline to serine, which is located in a variable region containing type-specific immunodominant epitopes. Thus, HIV[GUN-1V] acquired a wider host range than HIV[GUN-1WT] by a single point mutation in the env gene.     

Determination of octopine by pre-column fluorescence derivatization using benzoin

A sensitive fluorimetric method for the determination of octopine, a member of opine family, is presented. The method is based on the formation of a fluorescent derivative of octopine with benzoin and the separation by high performance liquid chromatography using a reversed-phase column (Kaseisorb LC ODS-300) within 20 min. The octopine derivative is completely separated from other guanidino compounds including arginine which is generally very high in marine invertebrates. This method gives higher sensitivity, 5 pmol minimum detection, and better reproducibility than the electrophoresis method and colorimetric method.