Old-age support system and policy reform in China

"With the on-going economic transition from the central planned system to a market-oriented system, the population aging process in China is also accelerating, and the support system for the elderly becomes an important issue demanding attention. With data from Chinese national statistics and a regional probability sampling survey in Wuhan Area, two supporting systems for the aged in China are examined in this paper. After a briefing of the population aging process in China, a detailed discussion of the two supporting systems, i.e. the formal and the informal support systems for the aged, including arrangement, operation and funding mechanisms of the systems, is made in terms of policy reform. Then follows an international comparison to highlight features and problems of the Chinese systems. Finally, solutions are proposed for the restructuring of China's pension systems."

[Detection of FMR-1 gene expression by RT-PCR]

Fragile X syndrome [FRA(X)] as the most common form of inherited mental retardation in man has an incidence of one per 1250 and is associated with a fragile site at Xq27.3. A gene was identified at the fragile X locus and was designated Fragile X Mental Retardation-1 (FMR-1). FRA(X) resulted from expansion of (CGG)n trinucleotide repeat in 5' untranslated region of the human FMR-1 gene, and was associated with abnormal methylation of a CpG island 250 bp proximal to this (CGG)n repeat. Males with typical FRA(X) showed repression of FMR-1 transcription and absence of FMR-1 protein, which was believed to contribute to the fragile X phenotype. FMR-1 mRNA extracted from leukocytes in normal and clinically suspected males were detected by RT-PCR. The methylation status and CGG expansion were also studied by PCR and Southern blot. Two of 10 clinically suspected males were found devoid of FMR-1 expression and accompanied with hypermethylation of the CpG island and CGG trinucleotide repeat expansion.

Synthesis and antimicrobial activity of 6,7-annulated pyrido[2,3-d]pyrimidines

Four new 6H-indeno[2',1':5,6]pyrido[2,3-d]pryimidines (10-13) were synthesized via cyclocondensation reactions involving chlorovinyl aldehyde 1 or ketoaldehyde 3 and appropriately substituted 6-aminopyrimidines. The regiochemistry of the compounds was established by 1H NMR and 13C NMR spectral data as well as X-ray crystal data. Compounds 10 and 11 and previously reported homologues 14 and 15 were screened for antimicrobial activity. Moderate antimicrobial activity was observed for some of these compounds. Compound 14 was especially active against Staphylococcus aureus. Crystal data for 13 (C14H7N3Cl2) follows: monoclinic space group, P21/n; Unit cell dimensions, a = 7.284(1) A, b = 12.800(1) A, c = 13.108(1) A, beta = 93.98(1) degree, V = 1219.2(2) A3, Z = 4.

Myocardial venous O2 saturation becomes more heterogeneous during hypoxic and carbon monoxide hypoxia

The hypothesis tested was that myocardial venous O2 saturation (SvO2) heterogeneity, a measure of microregional O2 supply/consumption balance, would increase under hypoxic and CO-hypoxia conditions. Since we are able to determine both O2 supply and the O2 supply/consumption ratio, we could also determine whether regional myocardial O2 consumption was heterogeneous. Twenty open-chest anesthetized dogs were studied under control and four hypoxic conditions, hypoxic hypoxia induced by ventilation with either an 8% O2 (SaO2 = 56%) or a 6% O2 (SaO2 = 40%) gas mixture for 20 min, or CO hypoxia induced by ventilation with a 1% CO gas mixture for either 7 min (SaO2 = 67%) or 20 min (SaO2 = 40%). Regional myocardial blood flow was measured using radioactive microspheres in 40 pieces (approximately 0.5 g) of the left ventricular free wall. Arterial and venous O2 saturations were determined with a four-wavelength microspectrophotometric method. A total of 28 veins (20-100 microns) were examined to determine SvO2 for each condition within each animal. The coefficient of variation (CV = SD/mean x 100), an index of heterogeneity, was calculated for both flow and SvO2 under each condition. Flow increased with increasing severity of hypoxia but its heterogeneity did not change with hypoxic or CO hypoxia. However, SvO2 heterogeneity significantly increased with increasing severity of hypoxia. A linear regression of SvO2 CV and mean SvO2 showed a significant correlation (CV = -0.84 (mean SvO2) + 51.1, R = 0.59). All possible myocardial O2 consumptions were calculated by multiplying all of the flows and O2 extractions. In 53 subepicardial and subendocardial measurements, only 10% of the flow and O2 supply/consumption heterogeneity observations could be explained by uniform O2 consumption if our acceptance criterion was 0.06-0.1 ml O2/min/100 g, and 50% could be explained with an acceptance criterion of 0.3-0.4 ml O2/min/100 g. Therefore, there must be some regional myocardial O2 consumption heterogeneity. The increase in venous O2 saturation heterogeneity during hypoxia may be due to increased variation in regional myocardial O2 consumption or variation in the control of O2 supply/consumption coupling.

(-)-Norcocaine

The title compound, [2R,3S-(2 beta,3 beta)]-methyl 3-(benzoyloxy)-8-azabicyclo[3.2.1]octane-2-carboxylate, C16H19NO4, is a metabolite of the tropane alkaloid cocaine. The molecule crystallized as the free base with the piperidine ring in a chair conformation. The tropane ring system and its methoxycarbonyl and benzoyl groups are rigid; only rotational flexibility is allowed in the conformation of the substituents.

Effect of hypoxic and carbon monoxide-induced hypoxia on regional myocardial segment work and O2 consumption

The purpose of this study was to investigate the potentially greater responses of regional myocardial work and O2 consumption to hypoxic hypoxia than to CO-induced hypoxia. Twenty open-chest anesthetized dogs were studied under control and four hypoxic conditions, hypoxic hypoxia induced with either 8% O2 (SaO2 = 56%) or 6% O2 (SaO2 = 40%) gas mixtures, or CO-induced hypoxia produced by a 1% CO gas mixture for either 7 min (SaO2 = 67%; SaCO = 30%) or 20 min (SaO2 = 40%; SaCO = 56%). Ultrasonic crystals and a force gauge were utilized to measure myocardial shortening and force. Regional myocardial segment work was calculated by integrating myocardial segment shortening multiplied by its corresponding force. Radioactive microspheres were used to measure regional coronary blood flow during each condition. Transmural biopsies were utilized to measure arterial and venous O2 saturation with a four-wavelength microspectrophotometric method. Regional O2 extraction and consumption were calculated. Regional coronary blood flow (77 +/- 38 ml/min per 100 g, control) increased with severe hypoxic hypoxia (293 +/- 206) and CO-induced hypoxia (150 +/- 128). Regional myocardial O2 extraction was decreased with both hypoxic and CO hypoxia. Regional myocardial O2 consumption was maintained even with severe hypoxic and CO hypoxia. Regional myocardial segment work/min increased from 343 +/- 205 g* mm/min with increasing levels of hypoxic hypoxia (564 +/- 677) and decreased with increasing levels of CO hypoxia (169 +/- 111). Regional segment work increased with increasing levels of hypoxic hypoxia and decreased with increasing CO hypoxia. The differential effects on segment work caused by the two types of hypoxia may be due to direct metabolic or autonomic differences.

The lipids of slugs and snails: evolution, diet and biosynthesis

There is a considerable gap in current knowledge of the lipid composition of snails and slugs, both of which belong to the phylum Mollusca. We have therefore analyzed the sterol and fatty acid compositions of three species of slugs and three species of snails. The sterols of slugs included eight different sterols: cholesterol contributed 76-85% of the total sterols, brassicasterol accounted for 4-13%; other sterols we identified were lathosterol, 24-methylene cholesterol, campesterol, stigmasterol, sitosterol and sitostanol. In contrast, snails contained two additional sterols, desmosterol and cholestanol. Of the polyunsaturated fatty acids in slugs, linoleic (18:2n-6) and arachidonic acids (20:4n-6) were the major n-6 fatty acids, while linoleic (18:3n-3) and eicosapentaenoic acids (20:5n-3) were the predominant n-3 fatty acids. Docosahexaenoic acid (22:6n-3), the end product in the n-3 fatty acid synthetic pathway and an important membrane fatty acid of mammals, fish and birds, was absent in both slugs and snails. However, the analogous product of n-6 fatty acid synthesis, 22:5n-6, was found in both snails and slugs. This raises speculation about preference for n-6 fatty acid synthesis in these species. Our data show the unique sterol and fatty acid compositions of slugs and snails, as well as similarities and differences in sterol composition between the two. The results between the two land mollusks are contrasted with those of marine mollusks, such as oysters, clams and scallops.

Prenatal ethanol exposure reduces phosphoinositide hydrolysis stimulated by quisqualate in rat cerebellar granule cell cultures

Prenatal ethanol exposure-induced alteration in poly-phosphoinositide (PPI) hydrolysis stimulated by excitatory amino acids (EAA) was studied in rat cerebellar granule cells previously labeled with [3H]myoinositol. The prenatal exposure to ethanol was achieved via maternal consumption of a Sustacal (chocolate flavored) liquid diet containing either 5% ethanol (w/v, 35% of calories) or isocaloric sucrose (pair-fed) substituted for ethanol from gestation d 11 until the day of parturition. The ionotropic glutamate receptor agonists, N-methyl-D-aspartate, kainate or (+/-)-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) (100 microM each) induced a two- to four-fold increase in PPI hydrolysis over the basal level, regardless of the liquid dietary treatment. Stimulation with quisqualate (QA), an agonist activating both metabotropic and ionotropic glutamate receptors, resulted in a much stronger and dose-dependent response in PPI hydrolysis and exposure in utero to ethanol significantly reduced this response. Tetrodotoxin, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), or (+/-)-3-(2-carboxypiperazine-4-yl)-propyl-1-phosphonic acid (CPP) had no effect on QA-stimulated PPI hydrolysis nor on the suppression of this hydrolysis by ethanol. Exposure in utero to ethanol did not affect PPI hydrolysis stimulated by a selective metabotropic glutamate receptor agonist, trans-(+/-)-l-amino-1,3-cyclopentanedicarboxylic acid (t-ACPD). Although the PPI hydrolysis stimulated by t-ACPD could be blocked by (RS)-alpha-methyl-4-carboxyphenylglycine (MCPG), an antagonist of the metabotropic glutamate receptor, MCPG was incapable of affecting QA-induced PPI hydrolysis and the suppressive effects of prenatal ethanol exposure on this hydrolysis. Taken together, the data suggest that the long-lasting suppressive effects of prenatal ethanol exposure on QA-stimulated PPI hydrolysis in cerebellar granule cell cultures is through a metabotropic QA receptor pathway that may be different from the one activated by t-ACPD.

Molecular analysis of HLA-DR beta and DQ beta polymorphism in Chinese with rheumatoid arthritis

OBJECTIVES

Several studies have suggested that genetic predisposition to rheumatoid arthritis may be related to the presence of specific polymorphic HLA sequences that are often associated with HLA-DR4 haplotypes. This study was performed to determine if an association exists between Chinese with rheumatoid arthritis and a particular HLA-DR beta or DQ beta subtype.

METHODS

This study used the polymerase chain reaction to amplify HLA-DR beta and DQ beta genes, and oligonucleotide probe hybridisation to examine the association of certain polymorphic sequences with rheumatoid arthritis in 23 Chinese patients from Shanghai.

RESULTS

An HLA-DR4 associated sequence was significantly increased in the Chinese patients (43%) compared with healthy controls (14%) from the same location (relative risk = 4.6, 95% confidence limits 1.1 to 19.3). Analysis of the third hyperpolymorphic region of DR4 positive samples was performed to detect polymorphic sequences associated with Dw4, Dw10, Dw13, Dw14, Dw15, and KT2 cellular specificities. Examination of this region showed that 91% of patients had sequences encoding amino acids QRRAA (associated with Dw14 and Dw15) or QKRAA (associated with Dw4) compared with 64% of the DR4 positive controls.

CONCLUSIONS

Rheumatoid arthritis in the Chinese is associated with HLA-DR4. There is a possible relationship between sequences within the third hyperpolymorphic region of the DRB allele and rheumatoid arthritis in the Chinese.

Systemic gene expression after intravenous DNA delivery into adult mice

Direct gene transfer into adult animals resulting in generalized or tissue-specific expression would facilitate rapid analysis of transgene effects and allow precise in vivo manipulation of biologic processes at the molecular level. A single intravenous injection of expression plasmid:cationic liposome complexes into adult mice efficiently transfected virtually all tissues. In addition to vascular endothelial cells, most of the extravascular parenchymal cells present in many tissues including the lung, spleen, lymph nodes, and bone marrow expressed the transgene without any apparent treatment-related toxicity. The transgene was still expressed in large numbers of cells in multiple tissues for at least 9 weeks after a single injection. Expression could be targeted to specific tissues and cell types, depending on the promoter element used.

Recombination of 4p16 DNA markers in an unusual family with Huntington disease

The Huntington disease (HD) mutation has been localized to human chromosome 4p16, in a 6-Mb region between the D4S10 locus and the 4p telomere. In a report by Robbins et al., a family was identified in which an affected individual failed to inherit three alleles within the 6-Mb region originating from the parental HD chromosome. To explain these results, it was suggested that the HD locus (HD) lies close to the telomere and that a recombination event took place between HD and the most telomeric marker examined, D4S90. As a test of this telomere hypothesis, we examined six members of this family, five of whom are affected with HD, for the segregation of 12 polymorphic markers from 4p16, including D4S169, which lies within 80 kb of the 4p telomere. We separated, in somatic cell hybrids, the chromosomes 4 from each family member, to determine the phase of marker alleles on each chromosome. We excluded nonpaternity by performing DNA fingerprint analyses on all six family members, and we found no evidence for chromosomal rearrangements when we used high-resolution karyotype analysis. We found that two affected siblings, including one of the patients originally described by Robbins et al., inherited alleles from the non-HD chromosome 4 of their affected parents, throughout the 6-Mb region. We found that a third affected sibling, also studied by Robbins et al., inherited alleles from the HD chromosome 4 of the affected parent, throughout the 6-Mb region. Finally, we found that a fourth sibling, who is likely affected with HD, has both a recombination event within the 6-Mb region and an additional recombination event in a more centromeric region of the short arm of chromosome 4. Our results argue against a telomeric location for HD and suggest that the HD mutation in this family is either associated with DNA predisposed to double recombination and/or gene conversion within the 6-Mb region or is in a gene that is outside this region and that is different from that mutated in most other families with HD.

Genetic characterization of the pnuC gene, which encodes a component of the nicotinamide mononucleotide transport system in Salmonella typhimurium

The pnuC gene, which encodes a component of the nicotinamide mononucleotide transport system, has been mapped and oriented. The gene order of the pnuC region, which is at min 17 of the Salmonella chromosome, is nadA-pnuC-aroG-gal. Polarity tests, with pnuC::Mu d-lac operon fusions, reveal that the pnuC gene is the promoter distal gene in an operon with the nadA gene, which encodes the second enzyme of the pyridine biosynthetic pathway. The nadA pnuC operon is regulated by the NadI repressor. The pnuC gene also has its own promoter, since strains with a nadA::Tn10d(Tc) insertion still express the pnuC gene at a low, unregulated level.

Identification of a repressor gene involved in the regulation of NAD de novo biosynthesis in Salmonella typhimurium

Mutations at the nadI locus affect expression of the first two genes of NAD synthesis, nadA and nadB, which are unlinked. Genetic data imply that the regulatory effects of nadI mutations are not due to indirect consequences of physiological alterations. Two types of mutations map in the nadI region. Common null mutations (nadI) show constitutive high-level expression of the nadB and nadA genes. Rare nadIs mutations cause constitutive low-level expression of nadB and nadA. Some nadIs mutations shut off the expression of the biosynthetic genes sufficiently to cause a nicotinic acid auxotrophy. Spontaneous revertants of auxotrophic nadIs mutants have a NadI- phenotype, including some with deletions of the nadI locus. The nadI locus encodes a repressor protein acting on the unlinked nadA and nadB genes.