Predictors of 30-day mortality and 90-day functional recovery after primary pontine hemorrhage

The factors related to death and functional recovery after primary pontine hemorrhage (PPH) in Koreans has not been well defined. The authors sought to identify independent predictors of death and functional recovery after PPH using data obtained at a single institute. Data were collected retrospectively on 281 patients with PPH admitted to the Stroke Unit at our hospital between January 1, 2000 and December 31, 2009. Multivariate logistic regression analysis was used to evaluate the associations between selected variables and 30-day mortality and 90-day functional recovery after PPH. One-hundred and ten patients (39.1%) died within 30 days of PPH and 27 patients (9.6%) achieved functional recovery within 90 days. By multivariate analysis, unconsciousness, dilated pupils, abnormal respiration, systolic blood pressure < 100 mmHg, hydrocephalus, and conservative treatment were found to be predictors of 30-day mortality, whereas consciousness, intact motor function, no history of hypertension or diabetes mellitus, intact eye movement, a hematoma volume of < 5 mL, no ventricular hemorrhage, and normally sized ventricle were found to be predictors of 90-day functional recovery. The present findings suggest that systolic hypotension of less than 100 mmHg may predict 30-day mortality and a history of underlying hypertension and diabetes mellitus may predict 90-day functional recovery.     

Semiquantitative histological examinations of the kidneys of rabbits (64-day, 100-day and 212-day series) with experimentally induced pyelonephritis

The kidneys of each 8 rabbits of a 64-day series (group E) and a 100-day series (group F) and of 6 rabbits of a 212-day series (group G) with experimentally induced unilateral hematogenous obstructive E. coli pyelonephritis were histologically examined and the glomerular and tubular lesions quantitatively evaluated using an ocular micrometer. An attempt was made to correlate the morphological changes with the results of simultaneous enzyme analyses (acid and alkaline phosphatases, glutaminase I).     

昆明小鼠3.5 d和4 d囊胚不同分离方法的比较

背景：远交系的昆明小鼠作为中国自然科学研究主要实验动物,其胚胎干细胞建系的成功率一直很低。 目的：探讨昆明小鼠胚胎干细胞体外分离培养的最佳方法和最适合的采胚时间。 方法：采集孕3.5 d和4 d的囊胚分别以免疫外科法和全胚培养法在小鼠胚胎成纤维细胞饲养层上分离和克隆昆明小鼠胚胎干细胞集落。 结果与结论：免疫外科法和全胚法培养3.5 d囊胚的内细胞团贴壁率和原代克隆形成率差异均不显著(P  > 0.05);全胚法培养4 d囊胚的内细胞团贴壁率显著高于免疫外科法(P < 0.05),但原代克隆形成率显著低于免疫外科法(P  < 0.05);全胚法培养4 d囊胚的原代克隆形成率显著高于3.5 d囊胚(P  < 0.05);免疫外科法分离4 d囊胚内细胞团的贴壁率和原代克隆形成率显著高于以同样方法分离培养的3.5 d囊胚(P  < 0.05)。结果显示用免疫外科法分离4 d囊胚更适合于昆明小鼠胚胎干细胞的体外分离培养。     

7天模拟失重对人体血液流变性的影响

航天飞行实践证明失重对血液循环系统有明显的影响，可引起心血管功能失调和航天贫血症。在探讨失重性血循环紊乱机理时，研究者们多着重于研究失重血液动力学的影响，而忽视了血液流变性在其中的作用。我们认为了解失重对血液流变性的影响，对于阐明航天中心血管系统和血液系统变化的机理，制定有效的防护措施都有一定的作用。本实验观察了6名被试者在7天模拟失重实验（－6度头低位卧床）中，血粘度、纤维蛋白原、血细胞压积、红细胞聚集指数的变化，说明头低位卧床可引起血液流变性指标的明显改变。主要表现在卧床第3天和第6天中纤维蛋白原、高、中、低三个切变率下的血粘度和红细胞聚集指数的明显增加。血细胞压积有增高趋势．但与卧床前相比无明显差别。统计学多元相关法分析的结果表明血细胞压积的改变不是引起模拟失重血粘度升高的主要原因。模拟失望所引起红细胞聚集和纤维蛋白原增高是造成协粘度改变的重要因素。本实验结果进一步证实我们提出的“航天血瘀症”假设的正确性。     

Intracellular hyperhydration induced by a 7-day endurance race

A group of 15 competitive male cyclists [mean peak oxygen uptake, V˙O_2peak 68.5 (SEM 1.5?ml?· kg^?1?·?min^?1)] exercised on a cycle ergometer in a protocol which began at an intensity of 150?W and was increased by 25?W every 2?min until the subject was exhausted. Blood samples were taken from the radial artery at the end of each exercise intensity to determine the partial pressures of blood gases and oxyhaemoglobin saturation (S _aO₂), with all values corrected for rectal temperature. The S _a O₂ was also monitored continuously by ear oximetry. A significant decrease in the partial pressure of oxygen in arterial blood (P _aO₂) was seen at the first exercise intensity (150?W, about 40% V˙O_2peak). A further significant decrease in P _aO₂ occurred at 200?W, whereafter it remained stable but still significantly below the values at rest, with the lowest value being measured at 350?W [87.0 (SEM 1.9) mmHg]. The partial pressure of carbon dioxide in arterial blood (P _aCO₂) was unchanged up to an exercise intensity of 250?W whereafter it exhibited a significant downward trend to reach its lowest value at an exercise intensity of 375?W [34.5 (SEM 0.5) mmHg]. During both the first (150?W) and final exercise intensities (V˙O_2peak) P _aO₂ was correlated significantly with both partial pressure of oxygen in alveolar gas (P _AO₂, r?=?0.81 and r?=?0.70, respectively) and alveolar-arterial difference in oxygen partial pressure (P _A?aO₂, r?=?0.63 and r?=?0.86, respectively) but not with P _aCO₂. At V˙O_2peak P _aO₂ was significantly correlated with the ventilatory equivalents for both oxygen uptake and carbon dioxide output (r?=?0.58 and r?=?0.53, respectively). When both P _AO₂ and P _A?aO₂ were combined in a multiple linear regression model, at least 95% of the variance in P _aO₂ could be explained at both 150?W and V˙O_2peak. A significant downward trend in S _aO₂ was seen with increasing exercise intensity with the lowest value at 375?W [94.6 (SEM 0.3)%]. Oximetry estimates of S _aO₂ were significantly higher than blood measurements at all times throughout exercise and no significant decrease from rest was seen until 350?W. The significant correlations between P _aO₂ and P _AO₂ with the first exercise intensity and at V˙O_2peak led to the conclusion that inadequatehyperventilation is a major contributor to exercise-induced hypoxaemia.     

Exercise thermoregulatory responses following a 28-day sleep-high train-low regimen

The potentiated exercise-sweating rate observed during acute hypoxia is diminished after a sleep-high train-low (SH-TL) regimen. We tested the hypothesis that this attenuation of the sweating response after SH-TL is compensated for by an increase in heat loss via vasodilatation. Nine male subjects participated in a 28-day SH-TL regimen. Before (pre-), and after (post-) the SH-TL protocol, they performed an $ \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} $ test under normoxia and hypoxia. Additionally, pre- and post-SH-TL they completed three 30-min constant-work rate trials on a cycle ergometer. In one trial, the subjects inspired room air while exercising at 50?% of normoxic $ \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} $ (CT). In the remaining trials, subjects exercised in hypoxia (F_IO₂ 12.5?%), either at the same absolute (HAT) or relative (50?% of hypoxic $ \dot{V}{\text{O}}_{{ 2 {\text{peak}}}} $ ) work rate (HRT) as in CT. Despite similar exercise core temperature responses between pre- and post-SH-TL trials, sweating rate was potentiated in HAT pre-SH-TL [CT: 1.97 (0.42); HRT: 1.86 (0.31); HAT: 2.55 (0.53)?mg?cm^?2?min^?1; p?<?0.05]. Post-SH-TL exercise sweating rate was increased for CT, and remained unchanged in HRT and HAT [CT: 2.42 (0.76); HRT: 2.01 (0.33); HAT: 2.59 (0.30)?mg?cm^?2?min^?1]. Pre-SH-TL, the forearm-fingertip skin temperature difference (Tsk_f?f) was higher in HAT than in CT and HRT by ~3.5°C (p?<?0.05). The inter-condition differences in Tsk_f?f were diminished post-SH-TL. In conclusion, the decrease in sweating rate during hypoxic exercise, following a SH-TL regimen, was countered by an increase in vasodilatation (reduced Tsk_f?f), whereas SH-TL enhanced the sweating response during normoxic exercise. The mechanisms underlying these SH-TL-induced alterations in thermoregulatory responses remain to be settled.     

Validation of a 7-day physical activity diary against doubly-labelled water

Background: The assessment of physical activity intensity and duration is essential for understanding group activity patterns.

Methods: The present study evaluated the validity of measurement of total energy expenditure (TEE) and physical activity level (PAL) using a categorized physical activity diary. In 29 young healthy men, aged 18–27 years, with body mass index range 21–43 kg m^?2, TEE using doubly-labelled water (DLW), resting metabolic rate (RMR) by indirect calorimetry, physical activity level (PAL defined as TEE/RMR) and activity pattern, timing and level from 7-day physical activity diaries were determined.

Results: TEE by DLW and estimated by activity diary were correlated (r?=?0.61, p?=?0.005). The mean underestimation of TEE by the activity diary compared with the DLW method was 2.50?±?0.72 MJ day^?1. Sedentary (lying, sitting and standing) time averaged 18 h day^?1 and was negatively correlated with PAL (r?=??0.44, p?=?0.018) whilst time spent in light intensity activity (5 h day^?1) was positively correlated (r?=?0.51, p?=?0.005).

Conclusions: It is concluded that the categorized physical activity diary measured TEE with limited accuracy but presents an inexpensive, convenient method of discriminating individual and group physical activity patterns.     

Cardiovascular responses to orthostatic tests after a 42-day head-down bed-rest

Cardiovascular responses to orthostatic tests were studied before and after a prolonged 42 day-head-down bed-rest (HDBR;?6°) experiment simulating a long duration space flight. Seven men participating in the experiment underwent stand tests (10?min) and lower body negative pressure (LBNP) tests (5?min at ?25, ?35, ?45?mmHg). Heart rate variability and spontaneous baroreflex response slope (SBS) were analysed to assess autonomic nervous system responses. Changes in plasma volume (PV) were assessed at the end of HDBR. At the end of HDBR, four subjects could not complete the stand tests and one could not complete the LBNP test. A higher stressed heart rate with standing (+44% before and +57% after HDBR) and LBNP exposure (+19% before and +34% after HDBR) were observed. A decrease in blood pressure (BP) reflecting a reduced vasomotor response was only observed with standing (mean BP +21% before and ?8% after HDBR); LBNP was less sensitive probably because it was performed 6?h after the stand test. The PV decreased by 10.6%. A decline in spectrum total power reflecting a reduced variance of RR-interval, a decrease in parasympathetic activity and an increase in sympathetic one were observed at the end of HDBR. The reduced parasympathetic indicator and SBS would suggest that the vagal nerve component of the cardiovascular control had been diminished. Except for a lower BP when standing after HDBR, no significant difference was observed between finishers and non-finishers. Autonomic nervous system changes including reduced vasomotor responses constituted important contributors to the orthostatic intolerance observed here and after space flights. Some autonomic and PV changes seemed to be opposite to those observed with training and would suggest a role of reduced physical activity in cardiovascular changes induced by HDBR.     

Behavior of rhesus monkeys during 28-day cycles of estrogen treatment

Sixteen ovariectomized rhesus monkeys were paired, each with two males, during thirty-two 28-day periods during which they received one or more of the following schedules of daily injections: (a) different mixtures of estradiol benzoate, progesterone, and testosterone propionate (artificial menstrual cycles), (b) the doses of estradiol benzoate given in artificial cycles but without the other hormones (cyclic estradiol regimens), and (c) appropriate control treatments (625 one-hour behavioral tests). Hormone doses were adjusted to give plasma levels in the physiological range (335 blood samples). Measures of male sexual activity during artificial cycles and during cyclic estradiol regimens showed significant cyclic changes, but these changes were indistinguishable from each other. In four females studied in an operant conditioning paradigm, there was a midcycle dip in the times taken to obtain access to males during the cyclic estradiol regimens. The data indicated that the estrogen state of the female plays a preponderant role in determining the cyclic changes in the behavioral interactions of the pair independently of the effects of other ovarian hormones.     

Whole muscle contractile parameters and thickness loss during 35-day bed rest

Extended exposure to microgravity leads to significant musculoskeletal adaptations. Contractile parameters of four skeletal muscles (biceps brachii-BB, vastus medialis-VM, biceps femoris-BF and gastrocnemius medialis-GM) were measured in ten healthy males (aged 22.3 +/- 2.2 years) during 35 days of horizontal bed rest by a mechanomyography-based method termed 'tensiomyography' (TMG). Two contractile parameters: contraction time (Tc) and maximal displacement (Dm) were individually measured from electrically evoked maximal single twitch TMG response of all four muscles before and after bed rest. Significant changes in Tc were found after bed rest, as shown by an increase in GM muscle Tc by 18% (p < 0.01). Dm values significantly increased (p < 0.01) after bed rest, by 24, 26 and 30% in the VM, BF and GM muscles, respectively. In the GM, the change in Dm significantly correlated with the decrease in muscle thickness (r = -0.70, p < 0.01). In conclusion, bed rest induced changes in both Dm and Tc of the TMG signal; changes in Dm being inversely related to those of muscle thickness. Amongst the investigated muscles, most affected, in terms of atrophy and mechanical alterations, were those of the lower limbs. The observed increase in Dm may be attributed to a decrease in muscle, as well as tendon stiffness, causing larger muscle fibre and non-contractile tissue oscillations following contraction.