Diet and phenylketonuria: time for change?

This article is a report of a meeting of dietitians held on 15 September 1992 in Birmingham to discuss the recommendations of a 'Medical Research Council Working Party on the Dietary Management of Phenylketonuria'. (Contributions on the day of the meeting came from Judith Houghton, Eleanor Weetch, Isabel Smith, Sheena Laing, Ruth Watling, John Walter, Rodney Pollitt.)     

The Effects of Na~+/Ca~(2+) exchange (NCX) on the Repolarization of Canine Ventricular Myocyte-Potential Arrhythmogenic Effect of NCX during a Mis-matched Repolarization and Relaxation Xiamen Zhongshan Hospital, Xiamen Medical College, Xiamen University

The Effects of Na~+/Ca~(2+) exchange (NCX) on the Repolarization of Canine Ventricular Myocyte-Potential Arrhythmogenic Effect of NCX during a Mis-matched Repolarization and Relaxation Xiamen Zhongshan Hospital, Xiamen Medical College, Xiamen University@巩燕$Visiting scholar of cardiac arrhythmia research institute,university hospital of Oklahoma!U.S.A @王焱 @BELA Szabo$Basic cardiac research laboratory,cardiac arrhythmia research institute,university hospital of Oklahoma!…     

两种剂量氟碳部分液体通气治疗犬吸入伤的比较研究

目的：对比研究两种剂量氟碳（PFC）部分液体通气（PLV）对蒸气吸入性损伤犬的血气和血流动力学的影响，方法：将健康犬15条随机分面两组，即PFC6ml/kg组（PFC－6）和PFC 12ml/kg(PFC-12)组，采用蒸气吸入造成吸入性损伤模型后经气管内注入PFC实施部分液体通气（PLV）治疗，观察治疗后30min,60min,90min血气，血流动力学参数的变化，结果：PFC－6组PaO2在PLV治疗30min后明显升高（P＜0．05），在治疗60min,90min生的PaO2与致伤值比较无统计学意义，而PFC－12组的PaO2在PLV治疗后30min,60min,90min均明显升高（P＜0．05），与PFC－6组相比，PFC－12组的PaO2,PvO2均呈上升趋势，但未达显著水平（P＞0．05），在PLV治疗后各时间点的PaCO2HR,MAP,CVP 致伤值相比均无明显变化（P＞0．05），两组之间比较，各对应时间点的PaCO2,HR,MAP,CVP也均无明显变化（P＞0．05），结论：氟碳部分液体通气是一种新的通气技术，它能明显改善蒸气入伤犬的氧合作用，对血液动力学参数无不良影响，两种剂量氟碳部分液体通气治疗蒸气吸入性损伤未呈现明显剂量一效应关系。     

经面罩机械通气治疗急性肺水肿的疗效观察

目的 研究经面罩机械通气(FMMV)对急性肺水肿的治疗效果。方法 34例肺水肿患者,分为对照组12例,采用常规治疗;治疗组22例,在常规治疗的基础上或常规治疗效果不佳的情况下给予FMMV,观察临床表现、胸部X线片和动脉血气的变化。结果 FMMV后30min内,91％的患者能较好耐受,所有患者呼吸困难皆明显改善,呼吸频率由(37±7)次/min降至(26±5)次/min(P<0.05),心率由(122±21)次/min降至(94±27)次/min(P<0.05),4例(18％)低血压患者血压迅速回升。77％的患者24h内咳嗽、咳痰和肺部湿啰音基本缓解。临床症状的总体好转速度治疗组明显高于对照组。吸氧流量相同的情况下,治疗组1h后PaO_2由(62±10)mm Hg升至(78±18)mm Hg(P<0.05),2～6h后升至(96±22)mm Hg(P<0.05),PaO_2升高的速度和幅度皆较对照组显著;脱机时,治疗组在吸空气条件下PaO_2维持在(79±8)mm Hg(P<0.05),PaCO_2和pH也逐渐恢复正常。95％的患者在24～48h内脱离呼吸机。结论 与常规治疗相比,FMMV可迅速改善心功能,并更快改善肺水肿和低氧血症。     

人参茎叶总皂甙对实验性小鼠生殖细胞遗传物质损伤的影响

本文采用小鼠精原细胞姐妹染色单体互换（ＳＣＥ）实验方法，研究了人参茎叶总皂甙（ＧＮＳ）对丝裂霉素Ｃ（ＭＭＣ）引起的小鼠精原细胞遗传物质损伤的影响。结果表明，ＧＮＳ不能诱发小鼠精原细胞ＳＣＥ，而且在腹腔注射ＭＭＣ的同时给予ＧＮＳ，可使ＭＭＣ诱发的小鼠精原细胞ＳＣＥ频率明显降低。为此，我们认为ＧＮＳ对小鼠生殖细胞遗传物质具有保护作用。     

Transfer of clonidine and dexmedetomidine across the isolated perfused human placenta

Background: The placental transfer of the a₂ receptor agonist clonidine, earlier used as an adjuvant in obstetric epidural analgesia, was compared with the transfer of the newer and more %-selective agonist dexmedetomidine.
Methods: Term placentas were obtained immediately after delivery with maternal consent and a 2-hour recycling perfusion of a single placental cotyledon was performed. Disappearance from the maternal circulation, accumulation in placental tissue and appearance in the fetal circulation of clonidine or dexmedetomidine with the reference compound antipyrine were followed in 4 experiments for both drugs.
Results: At 2 hours the percent dexmedetomidine found in the fetal circulation was 12.5 (SD 5.1)%, while 48.1 (SD 20.3)% was found in the perfused placental cotyledon. A higher mean clonidine than dexmedetomidine concentration was achieved in the fetal circulation (1.90 vs. 0.56 nmol/l, P <0.05). At 2 hours the percent clonidine found in the fetal circulation was 22.1 (SD 2.4)% ( P <0.05), while 11.3 (SD 3.3)% ( P <0.05) was re tained in the perfused placental cotyledon. The transfer indexes, describing maternal-to-fetal transfer of dexmedetomidine and clonidine normalized with the transfer of antipyrine, were 0.88 (SD 0.07) and 1.04 (SD 0.08) respectively ( P <0.05).
Conclusions: Dexmedetomidine disappeared faster than clonidine from the maternal circulation, while even less dexmedetomidine was transported into the fetal circulation. This was due to its greater placental tissue retention, the basis for which probably is the higher lipophilicity of dexmedetomidine.     

Differential Stimulation of Noradrenaline Release by Reversal of the Na+/Ca2+ Exchanger and Depolarization in Chromaffin Cells

We compared the effectiveness of Ca²⁺ entering by Na⁺/Ca²⁺ exchange with that of Ca²⁺ entering by channels produced by membrane depolarization with K⁺ in inducing catecholamine release from bovine adrenal chromaffin cells. The Ca²⁺ influx through the Na⁺/Ca²⁺ exchanger was promoted by reversing the normal inward gradient of Na⁺ by preincubating the cells with ouabain to increase the intracellular Na⁺ and then removing Na⁺ from the external medium. In this way we were able to increase the cytosolic free Ca²⁺ concentration ([Ca²⁺]_c) by Na⁺/Ca²⁺ exchange to 325 ± 14 nM, which was similar to the rise in [Ca²⁺]_c observed upon depolarization with 35 mM K⁺ of cells not treated with ouabain. After incubating the cells with ouabain, K⁺ depolarization raised the [Ca²⁺]_c to 398 ± 31 nM, and the recovery of [Ca²⁺]_c to resting levels was significantly slower. Reversal of the Na⁺ gradient caused an −6-fold increase in the release of noradrenaline or adrenaline, whereas K⁺ depolarization induced a 12-fold increase in noradrenaline release but only a 9-fold increase in adrenaline release. The ratio of noradrenaline to adrenaline release was 1.24 ± 0.23 upon reversal of the Na⁺/Ca²⁺ exchange, whereas it was 1.83 ± 0.19 for K⁺ depolarization. Reversal of the Na⁺/Ca²⁺ exchange appeared to be as efficient as membrane depolarization in inducing adrenaline release, in that the relation of [Ca²⁺]_c to adrenaline release was the same in both cases. In contrast, we found that for the same average [Ca²⁺]_c, the Ca²⁺ influx through voltage-gated channels was much more efficient than the Ca²⁺ entering through the Na⁺/Ca²⁺ exchanger in inducing noradrenaline release from chromaffin ceils. This greater effectiveness of membrane depolarization in stimulating noradrenaline release suggests that there is a pool of noradrenaline vesicles which is more accessible to Ca²⁺ entering through voltage-gated Ca²⁺ channels than to Ca²⁺ entering through the Na⁺/Ca²⁺ exchanger, whereas the adrenaline vesicles do not distinguish between the source of Ca²⁺.     

Insults to the body civil: Mistreatment of elderly in two Plains Indian tribes

The mistreatment of elderly is subject to various social constructions. On two geographically distinct Plains Indian Reservations which we call Lone Mountain and Abundant Lands, the abuse or neglect of elderly is construed as a health problem which is a dysfunction of the community as a whole. Both physical abuse and neglect are more common on the Lone Mountain Reservation, occurring in association with other indicators of community disorganization such as unemployment and substance abuse. On the Abundant Lands Reservation physical abuse was categorically denied and what neglect existed appeared to be a function of role strain, geographic dispersal, climate and terrain. We attribute differences in the prevalence of mistreatment of elders to variations in economic opportunities for younger residents. Examining the historical and present contexts of intergenerational relationships on the reservations, we discuss the implications of this study for social exchange theory and policy applications.This research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America AppliedThis research was supported by the Gerontological Society of America Applied     

Pathophysiological aspects of predominant preload lowering on pulmonary circulation, gas exchange, and the biventricular function in patients with chronic obstructive lung disease

A group of 21 patients with various degrees of chronic obstructive pulmonary disease underwent radionuclide ventriculography with hemodynamic monitoring to assess the extent to which pulmonary artery pressures and pulmonary vascular resistance can be lowered by the vasodilator molsidomine. Molsidomine (N-carboxy-3-morpholino-sydnonimin-ethylester) is similar to nitroglycerin in its mode of action. After hemodynamic and radionuclide data acquisition, at rest and during submaximal exercise in the steady state, 2 mg molsidomine was injected intravenously. Rest and exercise measurements were repeated 45 min after molsidomine injection. In patients with mild to moderate disease (group 1), pulmonary artery resting pressures decreased by 12% (p less than 0.05) at rest by 22% (p less than 0.01) during exercise after the administration of the drug. Total pulmonary resistance during exercise decreased significantly (p less than 0.01) as a result of marked decrease of pulmonary artery pressure (PAP) compared with a minimal decrease in cardiac index (CI). In patients with severe disease (group 2), only the resting values of PAP decreased while the relationship between pressure and flow was unchanged. During the exercise period, the preload parameters of the right and left ventricles decreased by an average of 30%. With regard to gas exchange, only the arterial PO2 at rest decreased slightly but significantly (p less than 0.05) after molsidomine, while the coefficient of oxygen delivery was not affected by the drug. However, in four patients arterial PO2 was markedly reduced by the drug. Right ventricular ejection fraction increased significantly (p less than 0.01) both at rest and during exercise in group 1 and during exercise in group 2 after administration of molsidomine.(ABSTRACT TRUNCATED AT 250 WORDS)