[A fixed cohort study of disability trajectory of the dying elderly in China].

Objective: To explore the trajectory of disability in the dying elderly in China. Methods: Based on the activity of daily living (ADL) data from the 2002-2018 Chinese Longitudinal Healthy Longevity Survey, the longitudinal item response theory (LIRT) model was fitted with the difficulty threshold parameters to analyze the ADL loss in the elderly in China. Then, a mixed-effects model was fitted to analyze the trajectory of the disability level of the dying elderly. Results: A total of 5 817 old adults who entered the cohort in 2002 were included, in whom 41.81% were males, with a baseline age of (86.80±12.40) years and a follow-up time of 4 (3,8) years. The results of LIRT showed that the lowest difficulty threshold parameter in the basic activity of daily living (BADL) was partially disability on bathing (0.41±0.05), and the highest was entirely disability on indoor movement (6.19±0.16). In comparison, the lowest difficulty threshold parameter in instrumental activity of daily living (IADL) was partially disability on using public transportation (-3.01±0.07), and the highest was entirely disability on visiting neighbors (1.51±0.07). In the trajectory of disability, the average dependency in ADL was lower in dying men than in dying women (P<0.001), in the elderly living alone than in the elderly living with family members (P<0.001) and in the non-illiterate elderly than in the illiterate elderly (P<0.001). The estimated value of both the linear change rate and quadratic coefficient of disability level development with time were 0.231 (P<0.001) and 0.002 (P<0.001). Conclusions: In China, the development of disability in the elderly in China has its characteristics, IADL disability might occurs earlier than BADL. Among the IADL/BADL items, the disability of lower limb-based items is more prone to occur compared with upper limb-based items, and the disability of complex items is more prone to occur compared with simple items, and the growth rate of the disability trajectory also accelerates over time. It is necessary to pay attention to old women, old people living with family members, old people with low education level and old people with poor cognitive function in the disability prevention.

Effect of angiotensin II on STAT3 mediated atrial structural remodeling.

OBJECTIVE: Atrial fibrillation (AF) has been identified to contribute significantly to the morbidity and mortality of cardiovascular disease patients. The atrial structural remodeling is a hallmark of AF and the molecular mechanisms underlying this remain unclear. Hence the objective of the present study is to determine the role of angiotensin II (Ang-II)/Ang-II type 1 (AT1) receptor--STAT3 signaling pathway on--atrial structural remodeling. MATERIALS AND METHODS: The method of this study involves incubation of atrial myocytes, with Ang-II, to increase the level of apoptosis expressions by Tunel assay and the expression of apoptosis related factors like caspase 3 and 8 release of cytochrome C from mitochondria to cytosol by western blot test after OGD pre-treatment. RESULTS: Atrial myocytes were shown to simulate the ischemia, hypoxia and atrial fibrillation. When incubated with Ang-II, (inhibited by losartan) the improvement was observed in the expression of caspase-3 and caspase-8. Ang-II also significantly promoted the transfer of cytochrome C levels from the mitochondria to the cytoplasm and this transfer was observed to be inhibited by losartan and WP1066. Ang-II incubation showed improved transcriptions of collagens and MMP expressions in atrial fibroblasts. In cultured atrial myocytes and fibroblasts, Ang-II induced tyrosine and serine phosphorylation of STAT3 showing interaction with MMP1 and MMP2 and DNA promoter sequences in atrial fibroblasts. The complete sequence was observed to have an affinity to be inhibited by losartan and WP1066. CONCLUSIONS: Ang-II/AT1 receptor/STAT3 is an important signaling pathway in the atrial structural remodeling, Ang-II enhances the apoptosis of atrial parenchyma and deposition of atrial ECM, which might contributes to atrial fibrillation.

Regional specificity of adaptation change in large elastic arteries of simulated microgravity rats.

This study was designed to test the hypothesis that a medium-term simulated microgravity by tail-suspension (SUS) induces hypertrophic and atrophic changes in the common carotid artery and abdominal aorta with their innermost smooth muscle (SM) layers being most profoundly affected. The second purpose was to elucidate whether vascular local renin-angiotensin system (L-RAS) plays an important role in the differential remodeling of the two kinds of large arteries by examining the gene and protein expression of angiotensinogen (AO) and angiotensin II receptor type 1 (AT1R) and their localization in the vessel wall. The results showed that SUS induced an increase in the media thickness of the common carotid artery due to hypertrophy of the four SM layers and a decrease in the total cross-sectional area of the nine SM layers of the abdominal aorta without significant change in its media thickness. Irrespective of the nature of remodeling, the most prominent changes were in the innermost layers. Immunohistochemistry, in situ hybridization, Western blot, and real time quantitative PCR analysis revealed that SUS induced an up- and down-regulation in AO and AT1R expression in the common carotid artery and abdominal aorta, respectively. In conclusion, our findings have demonstrated some special features in the structural adaptation of large elastic arteries due to a medium-term simulated microgravity.

Immunization against inhibin enhances both embryo quantity and quality in Holstein heifers after superovulation and insemination with sex-sorted semen.

The objective was to investigate the feasibility of improving embryo yield in superovulated cows following insemination with sex-sorted semen by prior immunization against inhibin. Twenty-eight heifers were allocated into three groups: High (n=10), Low (n=10), and Control (n=8). The High group received one primary (1mg) and two booster (0.5mg) vaccinations (28-d intervals) with a recombinant inhibin alpha-subunit in 1 mL of white oil adjuvant, whereas the Low group received half that dose, and the Control group received only adjuvant. After the last immunization, all heifers underwent a standard superovulation treatment (decreasing doses of pFSH for 4d), followed by two AI with 2 x 10(6) sex-sorted semen after the onset of estrus. Inhibin-immunized heifers had higher (P<0.01) plasma antibody titres, and an earlier onset of estrus (P<0.05) than Control heifers. The total number of embryo/ova, transferable, and grade 1 embryos in the High group (15.4+/-1.9, 5.7+/-0.7, and 3.8+/-1.0, respectively) was significantly greater than that of the Control group (9.1+/-1.2, 3.1+/-0.5, and 0.6+/-0.2), but was intermediate (P>0.05) in the Low group (13.0+/-2.3, 4.4+/-0.7, and 1.2+/-0.3). There were no significant differences among groups in number of unfertilized ova and degenerated embryos. The High group also had higher (P>0.05) plasma progesterone concentrations on the day of embryo collection. In conclusion, immunization against inhibin improved both embryo quantity and quality following superovulation and insemination with sex-sorted semen.

Broad-spectrum and selective serine protease inhibitors prevent expression of platelet-derived growth factor-BB and cerebral vasospasm after subarachnoid hemorrhage: vasospasm caused by cisternal injection of recombinant platelet-derived growth factor-BB.

BACKGROUND AND PURPOSE: Plasma serine protease cascade, including the complement system and thrombin, is activated in the subarachnoid space during the acute phase after subarachnoid hemorrhage (SAH). To examine the effect of protease cascade-based inflammation and subsequent vascular repair in the development of cerebral vasospasm, we examined the effect of 2 synthetic serine protease inhibitors-FUT-175, an inhibitor of thrombin and the complement system, and argatroban, a selective inhibitor of thrombin-on the development of cerebral vasospasm in a rabbit SAH model. METHODS: One hundred Japanese White male rabbits were used in the study. The SAH was simulated by a single injection of autologous arterial blood into the cisterna magna. To evaluate the development of cerebral vasospasm, the caliber of the basilar artery was measured on x-ray film before and at 2 days after SAH. Nine groups of rabbits (n=6 each) were treated with continuous intravenous injection of FUT-175 (2.5, 5, 10, or 20 mg/d), argatroban (1.25, 2.5, or 5 mg/d), or the same amount of saline (vehicle) for 48 hours, starting 40 minutes after SAH. Two days after SAH, the expression of homodimer of platelet-derived growth factor-BB (PDGF-BB) in the basilar artery was examined with immunohistochemical techniques. In 20 normal rabbits, 5 microg of recombinant PDGF-BB or vehicle was injected into the cisterna magna, and the basilar arteries were examined on angiograms for 48 hours. RESULTS: Significant differences were observed in the caliber of the basilar arteries between the vehicle group and the groups with the 3 larger doses of FUT-175 (vehicle, 52+/-5.0%; 5 mg, 79+/-5.7%; 10 mg, 80+/-2.5%; 20 mg, 80+/-3.7%) and between the vehicle group and the groups with the 2 larger doses of argatroban (vehicle, 52+/-6.4%; 2.5 mg, 81+/-9.0%; 5 mg, 85+/-4.1%) (P<0.05). In the histological examination, administration of effective doses of FUT-175 or argatroban suppressed the expression of PDGF-BB in the endothelial and medial smooth muscle cell layers. Exogenous PDGF-BB caused delayed and prolonged vasoconstriction on normal basilar arteries. CONCLUSIONS: Activation of the serine protease cascade and/or thrombin after SAH was demonstrated to play an essential role in the development of cerebral vasospasm. The expression of PDGF-BB-like protein in the arterial walls correlated with the development of cerebral vasospasm. Elevated PDGF-BB level in the subarachnoid space was found to induce delayed and chronic vasoconstriction.

Prolonged mild hypothermia therapy protects the brain against permanent focal ischemia.

BACKGROUND AND PURPOSE: The efficacy of hypothermic intervention for permanent focal ischemia has yet to be clarified. This study investigated the effect of a prolonged moderate or mild hypothermia on permanent focal ischemia in rats. METHODS: Two permanent focal ischemia models in male Sprague-Dawley rats were used. Moderate (30 degrees C, in experiment 1) or mild (33 degrees C, in experiment 2) hypothermia was achieved at the time of the induction of focal ischemia and was maintained for 2 hours under general anesthesia. Thereafter, the hypothermic condition was maintained by means of a cold room for a total of 24 hours. The infarct volume and neurological function were analyzed for a maximum of 21 days and compared with that of the normothermia group. Regional cerebral blood flow was monitored for 6 hours in the ischemic core and penumbra region. RESULTS: In experiment 1, the total infarct volume in the normothermic group was 368+/-59 mm(3); in contrast, it was significantly smaller in the hypothermia group: 169+/-33 mm(3) at 48 hours (mean+/-SEM, P:<0.05). In experiment 2, the infarct volume was 211+/-19 mm(3) in the normothermia group and 88+/-15 mm(3) in the hypothermia group at 21 days (P:<0.05). There were significant differences in neurological function from days 2 through 21 between the two groups. Mean regional cerebral blood flow in the penumbra region increased to a level >50% of baseline. CONCLUSIONS: Prolonged mild hypothermia suppressed the development of cerebral infarct and neurological deficit chronically after the induction of permanent focal ischemia.

Stimulatory effect of regucalcin on mitochondrial ATP-dependent calcium uptake activity in rat kidney cortex.

The effect of regucalcin, which is a regulatory protein of Ca(2+) signaling, on Ca(2+)-ATPase activity in isolated rat renal cortex mitochondria was investigated. The presence of regucalcin (50, 100, and 250 nM) in the enzyme reaction mixture led to a significant increase in Ca(2+)-ATPase activity. Regucalcin significantly stimulated ATP-dependent (45)Ca(2+) uptake by the mitochondria. Ruthenium red (10(-6) M) or lanthunum chloride (10(-6) M), an inhibitor of mitochondrial Ca(2+) uptake, markedly inhibited regucalcin (100 nM)-increased mitochondrial Ca(2+)-ATPase activity and (45)Ca(2+) uptake. The effect of regucalcin (100 nM) in elevating Ca(2+)-ATPase activity was completely prevented by the presence of digitonin (10(-2)%), a solubilizing reagent of membranous lipids, vanadate, an inhibitor of phosphorylation of ATPase, or dithiothreitol (50 mM), a protecting reagent of the sulfhydryl (SH) group of the enzyme. The activating effect of regucalcin (100 nM) on Ca(2+)-ATPase activity was not further enhanced by calmodulin (0.30 microM) or dibutyryl cyclic AMP (10(-4) M), which could increase Ca(2+)-ATPase activity. Trifluoperazine (TFP; 50 microM), an antagonist of calmodulin, significantly decreased Ca(2+)-ATPase activity. The activating effect of regucalcin on the enzyme was also seen in the presence of TFP, indicating that regucalcin's effect is not involved in mitochondrial calmodulin. The present study demonstrates that regucalcin can stimulate Ca(2+)-pump activity in rat renal cortex mitochondria, and that the protein may act on an active site (SH group) related to phosphorylation of mitochondrial Ca(2+)-ATPase.

[Effect of ascorbic acid on chemiluminescence of cells cultivated in various concentration of oxygen].

OBJECTIVE: To investigate the effect of Vitamin C (Vit. C) on the stimulated chemiluminescence of rabbit's pulmonary alveolus macrophage (AM) cultivated in various concentration of oxygen. METHOD: The AMs from rabbits were cultured in a thermostat in which luminescence from cells can be examined, then air with various concentrations of oxygen were continuously led in the device and the AM's stimulated chemiluminescence by PMA (phorbol myristate acetate) was measured with a chemiluminometer. RESULT: In the air with 0.5% O2, AM's survival rate and luminescence level were only 50% or 45% of the values before the exposure, and were reducing progressively with increasing dose of Vit. C in the culture medium. To increase the concentration of oxygen in the air was advantageous in enhancing cell's vitality and it can partly counteract the decrease of AM's stimulated chemiluminescence level by adding Vit. C into the culture medium. CONCLUSION: Oxygen in the air is important for cultivated cell's luminescence and survival, and it could lead to grave damage to the cultivated AMs when there is high concentration of Vit. C in the culture medium.

Expression of protein tyrosine phosphatase PTP-RL10 and its isoform in the mouse testis.

BACKGROUND: The cytoplasmic-type protein tyrosine phosphatase PTP-RL10/PTPD1/PTP2E contains an ezrin-like domain and associates with the c-Src protein tyrosine kinase. Because tyrosine phosphorylation regulated by protein tyrosine kinases and phosphatases is involved in activation, migration, differentiation and proliferation of various cell types, the expression of PTP-RL10 and c-src in the mouse testis was investigated. METHODS: Testes of wild-type mice and W/W(v) mutant mice that lack germ cells were analyzed by northern blotting, in situ hybridization histochemistry and reverse transcriptase-polymerase chain reaction for the expression of PTP-RL10, its isoform PTP-RL10b and c-src. Expression in the Sertoli cell lines, TM4 and TAMA26 was also analyzed. RESULTS: PTP-RL10 transcripts of 5.7kb and 2.9kb in size were detected in the testis. In situ hybridization histochemistry demonstrated that the 5.7kb transcripts were expressed in pachytene spermatocytes and somatic cells including Sertoli cells, in which c-src transcripts were detected. The 2.9kb transcript encoded a novel isoform, PTP-RL10b, that has the catalytic domain but not the domains that associate with c-Src. PTP-RL10b was expressed mainly in the testicular somatic cells. TM4 and TAMA26 cells were found to co-express PTP-RL10, PTP-RL10b and c-src transcripts. CONCLUSION: PTP-RL10 and its isoform are expressed in the Sertoli cells and are suggested to play roles in spermatogenesis by interacting with c-Src and/or other protein(s).

Cloning of human cDNAs for Apg-1 and Apg-2, members of the Hsp110 family, and chromosomal assignment of their genes.

In mice, the Hsp110/SSE family is composed of the heat shock protein (Hsp)110/105, Apg-1 and Apg-2. In humans, however, only the Hsp110/105 homolog has been identified as a member, and two cDNAs, Hsp70RY and HS24/p52, potentially encoding proteins structurally similar to, but smaller than, mouse Apg-2 have been reported. To clarify the membership of Hsp110 family in humans, we isolated Apg-1 and Apg-2 cDNAs from a human testis cDNA library. The human Apg-1 was 100% and 91.8% identical in length and amino acid (aa) sequence, respectively, to mouse Apg-1. Human Apg-2 was one aa shorter than and 95.5% identical in sequence to mouse Apg-2. In ECV304, human endothelial cells Apg-1 but not Apg-2 transcripts were induced in 2 h by a temperature shift from 32 degrees C to 39 degrees C. As found in mice, the response was stronger than that to a 37-42 degrees C shift. The human Apg-1 and Apg-2 genes were mapped to the chromosomal loci 4q28 and 5q23.3-q31.1, respectively, by fluorescence in-situ hybridization. We isolated cDNA and genomic clones encompassing the region critical for the difference between Apg-2 and HS24/p52. Although the primer sets used were derived from the sequences common to both cDNAs, all cDNA and genomic clones corresponded to Apg-2. Using a similar approach, the relationship between Apg-2 and Hsp70RY was assessed, and no clone corresponding to Hsp70RY was obtained. These results demonstrated that the Hsp110 family consists of at least three members, Apg-1, Apg-2 and Hsp110 in humans as well as in mice. The significance of HS24/p52 and Hsp70RY cDNAs previously reported remains to be determined.

Effects of ischemia and H2O2 on the cold stress protein CIRP expression in rat neuronal cells.

Expression of CIRP (cold-inducible RNA-binding protein) is inducible at 32 degrees C in cultured fibroblasts. Because ischemia is known to induce expression of heat shock proteins, its effect on the CIRP expression was examined using the rat transient forebrain ischemia model. The isolated rat CIRP cDNA encoded amino acids 100% identical in its sequence to mouse CIRP. Northern blot analysis revealed that the CIRP transcripts were ubiquitously expressed in various tissues. In situ hybridization histochemistry of normal rat brain revealed the expression of CIRP in neurons in the hippocampus and the cerebral cortex among others. In the hippocampus of postischemic rats, CIRP mRNA level decreased from 3-6 h after the onset of reperfusion, while it did not change in the cerebral cortex. When PC12 pheochromocytoma cells were cultured at 32 degrees C, the CIRP mRNA level was increased. The presence of H2O2 in the culture media inhibited dose dependently this induction as well as constitutive expression, suggesting that the effect of brain ischemia on CIRP expression is related to generation of reactive oxygen species. Further studies are necessary to clarify the roles played by cold shock proteins in the hypothermic therapy of brain damages.

Induction of Apg-1, a member of the heat shock protein 110 family, following transient forebrain ischemia in the rat brain.

Apg-1 (Osp94) and apg-2 belong to the heat shock protein (hsp) 110 family. In mouse somatic cells the apg-1 and hsp105/110 transcripts are inducible by a 32 degrees C to 39 degrees C heat shock, while apg-2 is not heat-inducible. Since ischemia is known to induce expression of hsp70, its effect on expression of apg-1 was assessed by using the 20-min forebrain ischemia model of the rat. In the cerebral cortex, Northern blot analysis and in situ hybridization histochemistry demonstrated an increased expression in neuronal cells of apg-1 transcripts 3 h after the onset of reperfusion, with a peak at 12 h, followed by a decline. In the hippocampus, the level was increased at 3 h, remained constant until 24 h, and then declined. Transcript levels of apg-2 as well as hsp 105 were also increased under the present conditions, indicating that the expression of apg-2 was differentially regulated in response to heat and ischemic stresses. The induction kinetics of hsp 105, but neither apg-2 nor hsp 70, were identical to those of apg-1. These results demonstrated that brain ischemia/reperfusion induced expression of each member of the hsp 110 family, although the regulatory mechanisms may not be the same. They also suggest a significant role of apg-1 in both the ischemic- and heat-stress responses and in the normal functioning of the non-stressed neuronal cells.

Diurnal change of the cold-inducible RNA-binding protein (Cirp) expression in mouse brain.

RNA-binding proteins are believed to play important roles in regulation of neural functions. Recently, a mouse cDNA encoding the cold-inducible RNA-binding protein, Cirp, has been isolated, the amino acid sequence of which showed similarity to plant circadian rhythm proteins. In the present study, diurnal expression of Cirp in the mouse nervous system was examined. Northern blot analysis showed that the level of Cirp mRNA was diurnally regulated in the brain but not in the testis and liver. The level increased during the daytime and decreased during the nighttime. Immunohistochemistry using an anti-Cirp antibody showed that Cirp was expressed in the nucleus of neurons and that the level of Cirp was diurnally regulated in the suprachiasmatic nucleus and the cerebral cortex. The diurnal regulation was not observed in the brain of adult mice kept in constant darkness nor that of 3-day-old mice. These findings suggest that Cirp plays a role in biological rhythms as known for plant proteins and that expression of Cirp is regulated differentially in discrete brain regions.

Increased transcript level of RBM3, a member of the glycine-rich RNA-binding protein family, in human cells in response to cold stress.

Although the cold-shock responses of microorganisms have been extensively investigated, those of mammalian cells are just beginning to be understood. Recently, CIRP, a member of the glycine-rich RNA-binding protein (GRP) family, has been identified as the first cold-shock protein in mammalian cells. Here, we report that RBM3, another member of the GRP family, is induced in human cells in response to cold stress (32 degrees C). RBM3 transcripts were constitutively expressed in all cell lines examined including K562, HepG2, NC65, HeLa, and T24 cells. In all of them, the transcript levels of RBM3 were increased at 24 h after the 37 to 32 degrees C temperature down-shift. In NC65 cells, the kinetics of RBM3 induction was different from that of CIRP. Protein synthesis inhibitors cycloheximide and puromycin induced RBM3 transcripts, but cadmium chloride, H2O2, ethanol, and osmotic shock had no effect. Combined with the different tissue distribution of expression, these results suggest that RBM3 and CIRP play distinct roles in cold responses of human cells.

PRL-1, a protein tyrosine phosphatase, is expressed in neurons and oligodendrocytes in the brain and induced in the cerebral cortex following transient forebrain ischemia.

Protein tyrosine phosphorylation is thought to play an important role in the regulation of neural function. We reported previously that CL100, a cytoplasmic type protein tyrosine phosphatase (PTP), was induced after transient forebrain ischemia. In the present study, changes in the mRNA levels after ischemia of PRL-1, a cytoplasmic type PTP and immediate-early gene similar to CL100, was examined. In situ hybridization histochemistry showed that PRL-1 mRNA was expressed in normal adult rats in neurons and oligodendrocytes in widespread regions including the cerebral cortex, hippocampus and cerebellum. PRL-1 mRNA was expressed in the developing brains on embryonic days 15 and 19 and postnatal day 1. Northern blot analysis showed that PRL-1 mRNA was induced from 6 h to 9 h after reperfusion in the cerebral cortex of postischemic rats. These findings suggest that PRL-1 plays a role in neurons and oliogodendrocytes, and that expression of PRL-1 mRNA is regulated by a mechanism different from those of other immediate-early genes such as c-fos and c-jun.

[Effects of chloroform, chlorobenzene and polychlorinated biphenyls on erythrocyte lipid peroxidation and membrane fluidity in poisoned rabbits].

Effects of three chlorinated compounds, i.e., chloroform, chlorobenzene and Aroclor 1254 (PCBs), on lipid peroxidation and membrane fluidity of erythrocytes in poisoned rabbits were studied. Results revealed daily intraperitoneal injection of peanut oil containing chlorinated compounds into rabbits showed nonenzymic promotion effects on its erythrocyte lipid peroxidation in varying degrees, but different effects on erythrocyte membrane fluidity, promoting by chloroform and inhibiting by Aroclor 1254. It suggested the constitutional characteristics of toxicant molecules also had effects on membrane fluidity. In addition, it was found there existed potential relationship between maintenance of cell morphology and membrane fluidity.