Characterization of recombinant human acidic fibroblast growth factor: comparative studies with bovine acidic fibroblast growth factor

Recombinant human acidic fibroblast growth factor (haFGF) was purified from E. coli lysate by heparin-sepharose affinity chromatography. The purified haFGF exhibited potent mitogenic activity in stimulating DNA synthesis in 3T3 cells and this activity could be significantly increased by heparin. By analysis of mitogenic activity and immunological properties, a marked difference was found between haFGF and bovine aFGF (baFGF). The main difference was that the heparin-dependence of haFGF was stronger than that of baFGF.

Chronic tonsillitis and IgA nephropathy

The authors studied the effect of tonsillectomy for IgA nephropathy and the relationship between chronic tonsillitis and IgA nephropathy. Forty-five patients with IgA nephropathy were treated by tonsillectomy in our department. The effective rate of hematuria type IgA nephropathy was 86.2% and that of non-hematuria type 62.5%. We also determined the immunoglobulin composition of the tonsilla tissue in 18 IgA nephropathy patients and compared it with that of 18 chronic tonsillitis patients. The immunoglobin level of the IgA nephropathy group was higher than that of the contrast group, indicating that the disorder of tonsilla immunity may be one of the pathogenic factors for IgA nephropathy. Since no specific method has been available for the treatment of IgA nephropathy, we use tonsillectomy as an effective procedure.

Structural analysis of the zinc hydroxide-Thr-199-Glu-106 hydrogen-bond network in human carbonic anhydrase II

The significance of the zinc hydroxide-Thr-199-Glu-106 hydrogen-bond network in the active site of human carbonic anhydrase II has been examined by X-ray crystallographic analyses of site-specific mutants. Mutants with Ala-199 and Ala-106 or Gln-106 have low catalytic activities, while a mutant with Asp-106 has almost full CO2 hydration activity. The structures of these four mutants, as well as that of the bicarbonate complex of the mutant with Ala-199, have been determined at 1.7 to 2.2 A resolution. Removal of the gamma atoms of residue 199 leads to a distorted tetrahedral geometry at the zinc ion, and a catalytically important zinc-bound water molecule has moved towards Glu-106. In the bicarbonate complex of the mutant with Ala-199 one oxygen atom from bicarbonate binds to zinc without displacing this water molecule. Tetrahedral coordination geometries are retained in the mutants at position 106. The mutants with Ala-106 and Gln-106 have a zinc-bound sulfate ion, whereas this sulfate site is only partially occupied in the mutant with Asp-106. The hydrogen-bond network seems to be "reversed" in the mutants with Ala-106 and Gln-106. The network is preserved as in native enzyme in the mutant with Asp-106 but the side chain of Asp-106 is more extended than that of Glu-106 in the native enzyme. These results illustrate the importance of Glu-106 and Thr-199 for controlling the precise coordination geometry of the zinc ion and its ligand preferences which results in an optimal orientation of a zinc-bound hydroxide ion for an attack on the CO2 substrate.

Acquired amegakaryocytic thrombocytopenic purpura with a Philadelphia chromosome

A 30-year-old Chinese man with acquired amegakaryocytic thrombocytopenic purpura (AATP) and a Ph chromosome is reported. At presentation, he had severe thrombocytopenia resulting in epistaxis, gingival bleeding, and ecchymoses, while other hematologic values were within the normal range. Bone marrow aspiration showed no megakaryocytes, with a normal appearance of erythroblastic and granulopoietic series. He failed to respond to prednisone treatment, and underwent a progress from isolated thrombocytopenia to full pancytopenia. At last he died of spontaneous intracranial hemorrhage. An in vitro culture for granulocyte-macrophage precursors showed very few colonies. Karyotypic analysis revealed a standard Ph chromosome translocation, t(9;22)(q34;q11), in the majority of bone marrow cells. Southern blot analysis using a 3' bcr-HE probe didn't detect a rearrangement within the bcr DNA sequence. This patient, in fact, was a myelodysplastic disorder, initially presenting as AATP. The diagnosis of chronic myelogenous leukemia was excluded on the basis of clinical and hematologic findings. The heterogeneity of Ph chromosome in myelodysplastic syndrome is discussed.

Importance of the conserved active-site residues Tyr7, Glu106 and Thr199 for the catalytic function of human carbonic anhydrase II

The catalytic mechanism of carbonic anhydrase includes the reaction of a zinc-bound hydroxide ion with the CO2 substrate. This hydroxide ion is part of a hydrogen-bonded network involving the conserved amino acid residues Thr199, Glu106 and Tyr7. To investigate the functional importance of these residues, a number of site-specific mutants have been made. Thus, Thr199 has been changed to Ala, Glu106 to Ala, Gln and Asp, and Tyr7 to Phe. The effects of these mutations on catalyzed CO2 hydration and ester hydrolysis have been measured, as well as the binding of some inhibitors. The results show that the CO2 hydration activity of the mutant with Phe7 is only marginally reduced, whereas the esterase activity is larger than that of unmodified enzyme. It is concluded that Tyr7 is not a functionally required element of the hydrogen-bonded network. The CO2 hydration activity (kcat as well as kcat/Km) and the esterase activity of the mutant with Ala199 are reduced about 100-fold. The affinity for the sulfonamide inhibitor, dansylamide, is only slightly reduced while the mutant has an enhanced affinity for bicarbonate and the anionic inhibitor, SCN-. The activities of the mutants with Ala106 and Gln106 are also reduced. The reduction of the esterase activity is about 100-fold, while kcat for CO2 hydration has decreased by a factor of 1000. The parameter kcat/Km is only about one order of magnitude smaller for these mutants than for the unmodified enzyme. The binding of dansylamide and another sulfonamide inhibitor, acetazolamide, are about 20-times weaker to the mutant with Gln106 than to unmodified enzyme. These results suggest important roles for Thr199 and Glu106 in carbonic anhydrase catalysis. The mutant with Asp106 is almost fully active suggesting that the structure has undergone a compensatory change to maintain the interaction between residue 106 and Thr199.

Complex karyotypic abnormalities including t(8;22) in a patient with chronic lymphocytic leukemia

The case of a 49-year-old Chinese man with B-cell chronic lymphocytic leukemia (B-CLL) is presented. Complex karyotypic abnormalities comprising t(8;22)(q24;q11), trisomy 7, a deletion of 11q, and two small marker chromosomes were observed in PWM-stimulated cultures of his peripheral blood cells. To our knowledge, this is the first report of a t(8;22) in CLL.

Crystallographic analysis of Thr-200-->His human carbonic anhydrase II and its complex with the substrate, HCO3-

A complex of carbonic anhydrase (CA) with one of its substrates, bicarbonate, has been studied crystallographically. Human isoenzyme II was mutated at position 200 from threonine to histidine, which results in higher affinity for bicarbonate. The HCO3- ion binds in the active site to the zinc ion as a pseudo-bidentate ligand which gives the metal a coordination geometry between tetrahedral and trigonal bipyramide. The water/hydroxide normally bound with tetrahedral coordination to the zinc is probably replaced by the OH group of the bicarbonate ion. The importance of residues Thr-199 and Glu-106 in controlling the binding orientation of HCO3- is discussed as well as the catalytic mechanism. Both the complex as well as the uncomplexed mutant were studied at 1.9 A resolution.

Specific chromosomal translocations and therapy-related leukemia induced by bimolane therapy for psoriasis

This paper reports for the first time results of cytogenetic studies on 14 consecutive secondary acute non-lymphocytic leukemia (S-ANLL) induced by bimolane therapy. They included 10 males and 4 females with ages ranging from 17 to 54 years. They had all suffered from psoriasis and received bimolane treatment before the occurrence of their leukemia. The total dose of bimolane ranged from 40 to 400 g (mean dose 194 g). The interval between the initiation of bimolane therapy and the diagnosis of leukemia was 12-96 months (median 30 months). A preleukemic phase was only found in one case. No dysplastic features in the hemopoietic series were seen in any patient. Chromosome analysis of bone marrow cells using banding techniques revealed clonal karyotypic abnormalities in all cases: t(15;17) in 8 cases of M3, of which 75% had extra abnormalities, t(8;21) in 4 cases of M2, del(7q) only in one case of M4 and one case of M5. After antileukemic therapy, complete remission was obtained in 10 out of 12 cases with specific translocations and one out of 2 cases with 7q-anomaly, respectively. The former survived 4-58 months (median 12 months), while the latter 1 and 9 months, respectively. This study indicates that: (1) bimolane is a causative factor of leukemia in this series; (2) the leukemia in our series is therapy-related leukemia (TRL) rather than de novo ANLL; (3) there exists, in fact, a new subgroup of TRL characterized by specific rearrangements, whose clinical, hematological and prognostic features and pathogenetic mechanism may be different from classical TRL characterized by chromosome abnormalities involving absence or deletion of parts of chromosome 5 and/or 7.

[Chemical constituents of the roots of Ostericum grosseserratum (Maxim.) Kitag]

This paper reports the isolation of eleven compounds from the roots of Ostericum grosseserratum, of which nine compounds were elucidated as myristic acid, palmitic acid, stearic acid, octacosanoic acid, succinic acid, beta-sitosterol, sitosterol-beta-D-glucoside, isoscopletin and sucrose. The results are helpful in the study of plant taxonomy.

[Serum levels of 25-hydroxyvitamin D in normal Beijing subjects]

This report describes the changes of serum Ca, P, ALP and 25-OH D3 (using protein binding assay) with age in 592 normal Beijing subjects, aged 0-87 years old. The results were: (1) There was highly negative correlation between age and 25-OH D3 (r = -0.380, P less than 0.01), especially after 41 years old, less between age and ALP and least with P and Ca. (2) There was a significant sex difference of 25-OH D3 and ALP (P less than 0.05). Their serum levels were higher in the male than in the female, indicating that the female is easier to suffer from metabolic bone disease than the male after 41 years of age. (3) There was a distinct seasonal variation in serum 25-OH D3 levels, which were lower in winter and Spring than in Summer and Autumn (P less than 0.001), indicating that there is a greater possibility of Vitamin D deficiency in Winter and Spring.

Green tea extract inhibits nucleoside transport and potentiates the antitumor effect of antimetabolites

The present study provides evidence that green tea extract (GTE), consisting of polyphenol components, is a highly active nucleoside transport inhibitor. GTE markedly inhibited radiolabeled thymidine and uridine transport in mouse leukemia L1210 cells, with IC50 values of 3.2 and 8.0 mumol/L, respectively. GTE blocked the rescue effect of exogenous nucleosides and enhanced the cytotoxicity of AraC and MTX to L1210 cells and human hepatoma BEL-7402 cells. GTE markedly potentiated the inhibitory effect of AraC on leukemia L1210 and P388 in mice. These results indicate that GTE is potentially useful when combined with antimetabolites in cancer chemotherapy.

[Proteoglycan and glycosaminoglycan from human femoral head cartilage]

The composition and the size of proteoglycans (PGs) and glycosaminoglycans (GAGs) from femoral head cartilage of different age were determined by caesium chloride density gradient centrifugation, sepharose chromatography and chemical analysis. The results showed that the size of PG subunits from articular cartilage decreases with increasing age. In PGs and GAGs from cartilage, uronic acid and galactosamine content decreased; the ratio of in keratin sulphate to chondroitin sulphate increased; glucosamine and hydroxyproline content decreased with age The cause of degenerative changes and the measures to prevent and treat them are discussed.

Treatment of functional headache with Chinese herbal inhalant--a report of 496 cases

Headaches of the neurofunctional type, blood vascular type, neuro-vascular type, and musculotonic type are commonly encountered clinically. The authors report a nasal inhalant of Chinese herbal drugs which has been effective in the treatment of these varieties of headache.

[Postburn changes in serum levels of calcitonin, parathyroid hormone and 25-hydroxycholecalciferol]

Postburn changes in serum levels of Alterations in serum Calcium (Ca), Phosphates (Pi), alkaline-phosphatase (ALP), calcitonin (CT), parathyroid hormone (PTH) and 25-hydroxy Vitamin D (25 OHD) levels in 14 burn patients were studied. The results indicated: (1) Hypocalcemia and hypophosphatemia occurred during burn shock. Hypocalcemia was closely associated with the degree of burn and patient's condition. (2) Serum CT and PTH levels were significantly increased in severe burn patients compared with controls on day 1. Then the parameters tended to decrease to normal levels. (3) CT/Ca ratio or CT/Pi ratio might be a sensitive index to indicate the degree of burn and patient's condition.

Plasmid deoxyribonucleic acid replication in Streptomyces griseus

A series of electron micrographs showing the presence of different molecular forms representing various replication stages of plasmid deoxyribonucleic acid from Streptomyces griseus was obtained. Based upon an analysis of these electron micrographs, a tentative model for plasmid deoxyribonucleic acid replication in S. griseus is proposed.