Heavy metal precipitation by polycation-polyanion complex of PEI and its phosphonomethylated derivative

The removal of various heavy metal ions such as Cu2+, Co2+, Zn2+, Ni2+ and Pb2+ from aqueous solutions by precipitation with polyelectrolyte complex of PPEI and PEI was conducted. Heavy metal binding with PPEI was initially allowed to occur and then upon equilibration, PEI was added to initiate precipitation of the polyelectrolyte complex together with the heavy metal ion. The PPEI-PEI system was found effective for heavy metal scavenging purposes even in the presence of high concentrations of non-transition metal ions like Na+. Heavy metal concentration may be reduced beyond emission standards for industrial wastewaters. The PPEI-PEI polyelectrolyte complex was found to be more effective than traditional precipitation methods for the treatment of a representative electroless Ni plating waste solution.     

Mechanisms responsible for resistance of sublines derived from leukemia cell lines to an antitumor agent 9-beta-D-arabinofuranosyl-2-fluoroadenine

An agent 9-beta-D-arabinofuranosyl-2-fluoroadenine (2-F-Ara-A) is a main metabolite of fludarabine, a fluorinated purine analogue with antitumor activity in lymphoproliferative malignancies. In this study, the mechanism responsible for the resistance of cancer cells to fludarabine was examined using the 2-F-Ara-A-resistant sublines JOK-1/F-Ara-A and L1210/F-Ara-A from a human hairy leukemic cell line (JOK-1) and a mouse leukemic cell line (L1210) respectively, which were established by continuous treatment of the parental cell lines with 2-F-AraA. JOK-1/F-Ara-A and L1210/F-Ara-A cells were more than 55 and 29 times more resistant to 2-F-Ara-A than were their parent cell lines, and showed a high cross-resistance to 1-beta-D-arabinofuranosylcytosine but not to doxorubicin or vincristine. These resistant sublines intracellularly accumulated almost the same amount of 2-F-Ara-A as did their parent cell lines. However, the amount of 2-F-Ara-ATP, a cytotoxic metabolite of 2-F-Ara-A, decreased by 2.6% (JOK-1/F-Ara-A C3), 6% (L1210/F-Ara-A C1) and 3.7% (L1210/F-Ara-A C7) relative to the levels in the parent cell lines. Enzymatically, these resistant cells hardly activated deoxycytidine (dCyd) and 2-F-Ara-A. In addition, the abilities to phosphorylate deoxyadenosine and deoxyguanosine were also decreased in the resistant cells in comparison with the parent cells. These findings suggest that the deficiency in activity of dCyd kinase may contribute to the resistance of 2-F-Ara-A.     

Deterioration of connectin/titin and nebulin filaments by an excess of protease inhibitors

OBJECTIVE: To investigate HLA class II allele associations with autoantibody responses to Ro/SS-A and La/SS-B among Japanese subjects. METHODS: Haplotype and allele distributions, along with molecular polymorphisms, of HLA class II genes were analyzed by polymerase chain reaction-restriction fragment length polymorphism in 41 Japanese women with precipitating autoantibodies to Ro/SS-A and/or La/SS-B. RESULTS: Among women with both Ro/SS-A and La/SS-B antibodies, the HLA class II haplotype DRB1*08032/DQA1*0103/DQB1*0601 and DRB1*08032 allele showed significantly increased frequencies compared with patients with anti-Ro/SS-A alone or with normal controls. All women with both anti-Ro/SS-A and anti-La/SS-B, but not those with anti-Ro/SS-A alone, carried DRB1 alleles that shared the same amino acid residues at positions 14-31 and 71 of the hypervariable regions of the DRB1 chain. All anti-Ro/SS-A positive women carried 1 or 2 alleles of DQB1*06 and DQB1*03 subtypes that shared the same amino acid residues at positions 71-77 of the DQB1 chain. HLA class II allele distributions did not differ among 3 anti-Ro/SS-A positive groups with different disease expressions, i.e., patients with systemic lupus erythematosus, patients with primary Sj?gren's syndrome, and women with no apparent symptoms of rheumatic disease. CONCLUSION: HLA class II allele distributions differ among anti-Ro/SS-A positive subjects according to the presence or absence of coexisting anti-La/SS-B antibodies, but not according to disease expression. Our findings suggest that different HLA class II molecules might control the development of anti-Ro/SS-A and/or anti-La/SS-B antibodies in the autoimmune response to the Ro/SS-A-La/SS-B complex.     

Reference values for bisphosphoglycerate mutase protein content and specific activity in human erythrocytes

Cytomegalovirus (CMV) gastritis has been reported in transplant patients. Symptoms are considered nonspecific, and gastroscopy with biopsy is usually performed to establish the diagnosis. Three patients are described here 1 to 3 months after solid organ transplantation, with primary CMV gastritis, confirmed by gastroscopy, histopathologic examination and cultures. The clinical presentation in all three cases was sharp epigastric pain that decreased in a supine position, increased while sitting and further increased when standing or walking. The epigastric pain completely resolved after treatment with ganciclovir. To the best of our knowledge, such postural epigastric pain has not been described as a specific symptom in any other clinical entity and may be a unique sign of primary CMV gastritis.     

Identification of three isoforms for the Na+-dependent phosphate cotransporter (NaPi-2) in rat kidney

We have isolated three unique NaPi-2-related protein cDNAs (NaPi-2alpha, NaPi-2beta, and NaPi-2gamma) from a rat kidney library. NaPi-2alpha cDNA encodes 337 amino acids which have high homology to the N-terminal half of NaPi-2 containing 3 transmembrane domains. NaPi-2beta encodes 327 amino acids which are identical to the N-terminal region of NaPi-2 containing 4 transmembrane domains, whereas the 146 amino acids in the C-terminal region are completely different. In contrast, NaPi-2gamma encodes 268 amino acids which are identical to the C-terminal half of NaPi-2. An analysis of phage and cosmid clones indicated that the three related proteins were produced by alternative splicing in the NaPi-2 gene. In a rabbit reticulocyte lysate system, NaPi-2 alpha, beta, and gamma were found to be 36, 36, and 29 kDa amino acid polypeptides, respectively. NaPi-2alpha and NaPi-2gamma were glycosylated and revealed to be 45- and 35-kDa proteins, respectively. In isolated brush-border membrane vesicles, an N-terminal antibody was reacted with 45- and 40-kDa, and a C-terminal antibody was reacted with 37-kDa protein. The sizes of these proteins corresponded to those in glycosylated forms. A functional analysis demonstrated that NaPi-2gamma and -2alpha markedly inhibited NaPi-2 activity in Xenopus oocytes. The results suggest that these short isoforms may function as a dominant negative inhibitor of the full-length transporter.     

A novel anionic surfactant templating route for synthesizing mesoporous silica with unique structure

Anionic surfactants are used in greater volume than any other surfactants because of their highly potent detergency and low cost of manufacture. However, they have not been used as templates for synthesizing mesoporous silica. Here we show a templating route for preparing mesoporous silicas based on self-assembly of anionic surfactants and inorganic precursors. We use aminosilane or quaternized aminosilane as co-structure-directing agent (CSDA), which is different from previous pathways. The alkoxysilane site of CSDA is co-condensed with inorganic precursors; the ammonium site of CSDA, attached to silicon atoms incorporated into the wall, electrostatically interacts with the anionic surfactants to produce well-ordered anionic-surfactant-templated mesoporous silicas (AMS). These have new structures with periodic modulations as well as two-dimensional hexagonal and lamellar phases. The periodic modulations may be caused by the coexistence of micelles that differ in size or curvature, possibly owing to local chirality. These mesoporous silicas provide a new family of mesoporous materials as well as shedding light on the structural behaviour of anionic surfactants.     

Isolation of mRNAs induced by a hazardous chemical in white-rot fungus, Coriolus versicolor, by differential display

During January through December 1993, twelve symptomatic infants and children (6 females, 6 males) with human immunodeficiency virus infection were prospectively evaluated for their cardiovascular clinical manifestations and ventricular functions, using two-dimensional, M-mode and Doppler echocardiographic examination. From auscultation, the pulmonic component of the second heart sound was accentuated in 8 cases and the murmur of atrioventricula valve regurgitation and pericardial friction rub were audible in 7 and 6 patients, respectively. Cardiomegaly and venous congestion were present on chest roentgenogram in 6 cases and electrocardiogram was abnormal in 5. The echocardiogram demonstrated elevated pulmonary arterial pressure in 9 patients. There were 5 cases of non-tamponade pericardial effusion. Five patients had mitral and pulmonary insufficiency while six had tricuspid insufficiency. The ejection fraction and shortening fraction were increased in all. The incidence of pulmonary hypertension was more frequent than previously reported.     

Sialon formation by Si+ and N2 + ion implantation into sapphire

Single-crystal alumina was implanted firstly with 400 keV Si⁺ and subsequently with N₂ ⁺ ions and then annealed at 1673 K in an No atmosphre. The implanted layers were characterized by means of X-ray diffraction, Rutherford backscattering-channelling of 2 MeV He⁺ ions, and the resonance nuclear reaction¹⁵N(p,)¹²C. The annealing of sapphire implanted at ambient temperature resulted in the formation of-sialon, a solid solution of-silicon nitride and alumina in the subsurface layer, while implantation at 100 K resulted in the formation of aluminium oxynitride in the surface layer. In the latter case, the implanted silicon atoms were believed not to react vxi1h the implanted nitrogen atoms but with the substrate oxygen atoms. These crystalline precipitates were found to have epitaxial relations with the sapphire substrate.     

In vivo studies on chiral inversion and amino acid conjugation of 2-[4-(3-methyl-2-thienyl)phenyl]propionic acid in rats and dogs

The relationship between chiral inversion and stereoselective amino acid conjugation of a new nonsteroidal anti-inflammatory agent, R, S-2-[4-(3-methyl-2-thienyl)phenyl]propionic acid (R,S-MTPPA) was investigated in rats and dogs. Only the S-enantiomer was found in plasma after oral administration of S-MTPPA to both species. In contrast, the R- and S-enantiomers were both detected after the dosing of R-MTPPA. In rats, the area under the curve of S-MTPPA in plasma was only 9% of that of R-MTPPA when R-MTPPA was dosed, whereas in dogs it was 2.5 times larger than that of the R-enantiomer. After administration of R-MTPPA, both enantiomers appeared in the urine. In rats, a small amount of S-enantiomer was found in the urine, whereas in the case of dogs the amount of the S-enantiomer was larger than that of the R-enantiomer. It appears that R-MTPPA is chirally inverted to S-MTPPA in both rats and dogs, although the extent of chiral inversion is greater in dogs than in rats. In dogs, the taurine conjugate was detected in plasma, urine and feces as a major metabolite after oral administration of either R- or S-MTPPA. In this case, only S-MTPPA-taurine was detected in the urine after the administration of S-MTPPA, and it was also the main component after administration of R-MTPPA.