Injury in the aging: recovery and rehabilitation

Interest in how victims of traumatic injuries recover is increasing and a number of observational studies have now been done. There are very few intervention studies aimed at enhancing recovery, but there will be more as our knowledge base grows. Older recipients of traumatic injuries differ from the young in the types of injuries they sustain, in the way they respond to their injuries and in the consequences of even relatively minor injuries on their future independence. In this paper, we summarise our understanding of recovery after injury and consider this in more depth for older people with specific injuries.     

Exposure to nicotine enhances acquisition of ethanol drinking by laboratory rats in a limited access paradigm

 Observations in humans suggest that the initial use of tobacco occurs in close temporal proximity to experimentation with alcohol. There have been relatively few research reports, however, examining possible interactions between these two agents. The present experiments examined the effect of nicotine exposure on the acquisition of ethanol drinking behavior in a limited access procedure. In experiment 1, rats were presented with 1-h access to ethanol solutions of increasing concentration for a period of 20 days. Subcutaneous injections of nicotine (0.6 or 1.2 mg/kg salt) or vehicle were administered 30 min prior to each ethanol presentation. Experiment 2 used a similar method, but rats were presented with water along with ethanol during the 1-h test session. Mecamylamine, a nicotinic receptor antagonist, was administered 30 min prior to the nicotine treatment. Nicotine was seen to produce a dose-dependent increase in ethanol drinking behavior which commenced at the 5% ethanol concentration and continued at 8% and again at 10%. In the second experiment, mecamylamine was observed to block completely the nicotine-induced increase in ethanol drinking behavior. The findings suggest that exposure to nicotine can facilitate the acquisition of ethanol drinking behavior in naive rats and that this effect is mediated by nicotine’s interaction at the nicotinic-cholinergic receptor. Received: 11 June 1998 / Final version: 1 October 1998     

Hemin enhances the in vitro growth of primitive erythroid progenitor cells

Since exogenous hemin has been shown to exert a variety of stimulatory effects on erythroid cells, including the augmentation of hemoglobin synthesis, we determined its effect on early stages of erythroid development by employing clonal cells assays. The addition of hemin at a concentration of 2 X 10(-4) M to cultures of normal murine marrow substantially increased the observed number of primitive BFU-E, which was in contrast to its lack of an effect on more mature erythroid colony-forming cells. This cell-specific enhancement of primitive BFU-E resulted in marrow frequencies equivalent to or exceeding those reported in the presence of "burst-promoting activity." In the presence of hemin, the number of BFU-E was also observed to be linearly related to the number of cells plated at very low plating densities, and the cell titration curve was observed to extrapolate to the origin. The evidence suggests that hemin may be a primary growth regulator of early developmental stages of erythroid progenitor cells.     

National study of the impact of managed care on osteopathic physicians

The study reported here was designed to provide insight into the impact managed care has had on osteopathic physicians' ability to practice medicine, as well as data to substantiate the prevalence of the specific problems encountered by the 40,000 osteopathic physicians in the United States. New data on the extent to which osteopathic physicians use osteopathic manipulative treatment was also obtained, as a review of the literature revealed only two previous surveys on the use of osteopathic manipulative treatment. The American Osteopathic Association hired an independent research company to conduct the survey.     

Assessment of the mutagenicity of dichloroacetic acid in lacI transgenic B6C3F1 mouse liver

Dichloroacetic acid (DCA) is a chlorination byproduct found in finished drinking water. When administered in drinking water this chemical has been shown to produce hepatocellular adenomas and carcinomas in B6C3F1 mice over the animal's lifetime. In this study, we investigated whether mutant frequencies were increased in mouse liver using treatment protocols that yielded significant tumor induction. DCA was administered continuously at either 1.0 or 3.5 g/l in drinking water to male transgenic B6C3F1 mice harboring the bacterial lacI gene. Groups of five or six animals were killed at 4, 10 or 60 weeks and livers removed. At both 4 and 10 weeks of treatment, there was no significant difference in mutant frequency between the treated and control animals at either dose level. At 60 weeks, mice treated with 1.0 g/l DCA showed a 1.3-fold increase in mutant frequency over concurrent controls (P = 0.05). Mice treated with 3.5 g/l DCA for 60 weeks had a 2.3-fold increase in mutant frequency over the concurrent controls (P = 0.002). The mutation spectrum recovered from mice treated with 3.5 g/l DCA for 60 weeks contained G:C-->A:T transitions (32.79%) and G:C-->T:A transversions (21.31%). In contrast, G:C-->A:T transitions comprised 53.19% of the recovered mutants among control animals. Although only 19.15% of mutations among the controls were at T:A sites, 32.79% of the mutations from DCA-treated animals were at T:A sites. This is consistent with the previous observation that the proportion of mutations at T:A sites in codon 61 of the H-ras gene was increased in DCA-induced liver tumors in B6C3F1 mice. The present study demonstrates DCA-associated mutagenicity in the mouse liver under conditions in which DCA produces hepatic tumors.      

Fatty acid balance studies in term infants fed formula milk containing long-chain polyunsaturated fatty acids

Long-chain polyunsaturated fatty acids (LCP) are thought to be required for optimal nervous system development in the newborn. A commercial milk formula containing LCP (Aptamil-LCP) with a fatty acid profile closely resembling breast milk, has recently been introduced for term infants. The absorption of fatty acids in term infants was examined in a double-blind randomized controlled trial comparing Aptamil-LCP ( n = 20) and standard Aptamil ( n = 20). Formula-fed newborn infants were studied from birth for 14 d. Fat balances (3 d) were performed from d 10. A 3-d stool collection was performed from d 10 in a parallel breastfed group ( n = 21). Plasma samples were taken on d 6. Median fat excretion (mg kg⁻¹) was 897.1, 615.0 and 355.2 with Aptamil, Aptamil-LCP and breastfeeding, respectively. The median total fat absorption coefficient in Aptamil-LCP-fed infants was higher than in those fed standard Aptamil ( p < 0:01). These findings were accounted for by differences in the excretion and absorption of long-chain saturated fatty acids (C14:0, C16:0 and C18:0). Higher fat excretion was associated with bulkier and firmer stools. Only trace amounts of LCP were detected in the stools of all groups. This accounted for less than 4% of dietary intake in Aptamil-LCP-fed infants. No differences in the utilization of LCP from Aptamil-LCP and breast milk feeding were apparent. Plasma phospholipid fatty acid composition data reflected differences in dietary LCP intake. Thus, PL LCP levels were highest in the breastfed infants and lowest in the Aptamil-fed infants, with values for the Aptamil-LCP-fed group falling in between.     

Improved contractility of obstructed bladders after Tadenan treatment is associated with reversal of altered myosin isoform expression

PURPOSE: Tadenan is a plant extract from Pygeum africanum used in the treatment of benign prostatic hyperplasia, to protect the bladder from contractile dysfunction induced by partial bladder outlet obstruction (BOO). The aim of the present study was to determine whether the Tadenan-induced return of detrusor contractility affects the expression of myosin isoforms, which differ at the C-terminal (SM1 and SM2) and the N-terminal regions (SM-A and SM-B). MATERIALS AND METHODS: Four groups of New Zealand White rabbits (3 to 5 kg., 4 to 6 rabbits per group) were either partially obstructed by ligation of the urethra (groups 1 and 2) or not obstructed (groups 3 and 4). After 2 weeks, rabbits from groups 2 and 4 received Tadenan in peanut oil (vehicle) orally at 100 mg. /kg./day for 3 weeks and rabbits in groups 1 and 3 received vehicle only. Rabbits were sacrificed and bladders were removed and weighed. Contractility studies were performed on isolated strips of detrusor and the remaining muscular layer from the bladder body was used to study the expression of myosin heavy chain (MHC) isoforms at mRNA (SM1, SM2, SM-A, and SM-B) and the protein (SM1 and SM2) levels by RT-PCR and SDS-PAGE analyses, respectively. RESULTS: Tadenan significantly reduced the effect of BOO on bladder mass. The diminished contractile response to field stimulation and carbachol secondary to urethral obstruction was significantly reversed by Tadenan treatment. The relative ratios for MHC isoforms were altered at the mRNA (SM2:SM1 and SM-A:SM-B) and protein (SM2:SM1) levels in obstruction. Upon treatment with Tadenan, the ratio of these isoforms returned to normal, as shown at the mRNA levels. In addition, the altered relative ratio of SM2:SM1 at the protein level also returned to nearly normal values after treatment. CONCLUSIONS: Improvement of obstruction-induced contractile dysfunction of the detrusor following treatment with Tadenan is associated with changes in the expression of myosin isoforms. The alteration in the expression of myosin isoforms associated with obstruction-induced hypertrophy is reversed close to normal in the detrusor smooth muscle from Tadenan-treated obstructed rabbits.     

代谢综合症基线调查

目的：通过对豫宛市30岁以上人群代谢综合症（MS）发病率的词查、统计和分析，旨在唤起人们对此病的重视和预防。方法：利用年度体检之机采用三级分组法对30岁以上人群进行有关MS指标的检测和统计，依据亚洲及我国体重指数标准及2004年中华医学会糖尿病分会诊断代谢综合症标准。共计调查人数3987人（男1981人，女2006人）。结果：30岁以上MS患病率，青年有10％～13％，中老年后可渐增至20％～30％。结论：MS是中老年多见的代谢异常疾病。已严重威胁着人们的生命健康。