Temperature regulation in a hypometabolic primate, the slow loris (Nycticebus coucang).

Six slow loris were exposed to air temperatures between 10 degrees C and 40 degrees C. Rectal temperature was stable (mean, 34.8 degrees C) at air temperatures between 17 degrees C and 31 degrees C; at higher air temperatures, the animals became hyperthermic. Oxygen consumption was minimal at air temperatures of 31.4-36.6 degrees C; the mean value (0.250 ml O2 g-1 h-1) was only 36% of the expected level for a eutherian Mammal. The slow loris increased its heat production at lower air temperatures. Thermal polypnea occurred in response to heat, and some of the animals were able to dissipate their entire metabolic heat production at lower air temperatures. Thermal polypnea occurred in response to heat, and some of the animals were able the combined thermal conductance of the tissues and haircoat was 73% of the predicted values. It was concluded that, in spite of its low metabolic rate, the slow loris had effective responses to moderate cold, and that, in addition, it was well adapted to a hot climate.     

The origin of four squirrel monkey cell lines established by karyotype analysis

The squirrel monkey is a neotropical primate genus which is widely used in biomedical research but includes individual species and subspecies that respond differently to experimental perturbations. GTG-banding patterns of chromosomes 15 and 16, which are distinct among different squirrel monkey species and subspecies, were used to determine the origin of three lung fibroblast cell lines from squirrel monkeys of unknown genetic background (DPSO 114/74, SqMkLu/68, and 7603830) and to confirm the origin of a lymphoblast cell line (GSML) recently established from Guyanese squirrel monkey. DPSO 114/74 cells are from Peruvian squirrel monkey, SqMkLu/68 cells are Bolivian squirrel monkey, and 7603830 cells are from a Peruvian/Bolivian hybrid. Chromosome analysis of GSML cells confirmed that they are from Guyanese squirrel monkey.     

556例多发伤患者的急诊救治临床分析

目的探讨多发伤患者的救治策略。方法回顾分析我科2000年1月至2008年5月急诊抢救的556例多发伤患者的临床资料。结果 16例患者经抢救无效死亡,死亡率2.88%;其余患者均经紧急抢救及行必要实验室检查,病情稳定,好转率达97.12%。平均抢救时间为(1.37±1.05)h。结论强化多发伤的急诊科早期救治,树立创伤急救"黄金1 h"观念,是提高多发伤患者生存率及降低死亡率的关键。     

Absence of pituitary prolactin epitopes in immunoreactive prolactin of rat brain.

Immunoreactive prolactin (ir-PRL) in rat brain has been consistently documented. However, the identity of this ir-PRL is controversial. Ir-PRL is defined by its ability to bind to PRL antibodies. All previous studies of brain ir-PRL have used polyclonal antibodies, at least one of which apparently crossreacts with a portion of the proopiomelanocortin molecule. To begin to define the epitopes comprising ir-PRL in the brain, we utilized two monoclonal antibodies (MAb) that recognize pituitary PRL in a variety of species, including rat. Immunocytochemistry was performed on rat brains and pituitary glands using two monoclonal and one polyclonal PRL antibody. Although both MAb immunostained lactotrophs of the rat pituitary gland, neither antibody immunostained cell bodies or neuronal processes in the brain. However, the polyclonal antiserum immunostained lactotrophs and a system of neuronal cell bodies and processes in the brain. Thus, epitopes found in pituitary PRL from several species are not found in ir-PRL in rat brain.     

Flux Analysis of Glucose Metabolism in Rhizopus oryzae for the Purpose of Increasing Lactate Yields

A flux analysis of glucose metabolism in the filamentous fungus Rhizopus oryzae was achieved using a specific radioactivity curve-matching program, TFLUX. Glycolytic and tricarboxylic acid cycle intermediates labeled through the addition of extracellular [U-14C]glucose were isolated and purified for specific radioactivity determinations. This information, together with pool sizes and the rates of glucose utilization and end product production, provided input for flux maps of the metabolic network under two different experimental conditions. Based upon the flux analysis of this system, a mutant of R. oryzae with higher lactate and lower ethanol yields than the parent was sought for and found.     

Narcolepsy in orexin knockout mice: molecular genetics of sleep regulation.

Neurons containing the neuropeptide orexin (hypocretin) are located exclusively in the lateral hypothalamus and send axons to numerous regions throughout the central nervous system, including the major nuclei implicated in sleep regulation. Here, we report that, by behavioral and electroencephalographic criteria, orexin knockout mice exhibit a phenotype strikingly similar to human narcolepsy patients, as well as canarc-1 mutant dogs, the only known monogenic model of narcolepsy. Moreover, modafinil, an anti-narcoleptic drug with ill-defined mechanisms of action, activates orexin-containing neurons. We propose that orexin regulates sleep/wakefulness states, and that orexin knockout mice are a model of human narcolepsy, a disorder characterized primarily by rapid eye movement (REM) sleep dysregulation.     

Increased production of 11beta-hydroxysteroid dehydrogenase type 2 in the kidney microsomes of squirrel monkeys (Saimiri spp.)

In squirrel monkeys (Saimiri spp.), cortisol circulates at levels much higher than those seen in man and other Old World primates, but squirrel monkeys exhibit no physiologic signs of the mineralocorticoid effects of cortisol. These observations suggest that squirrel monkeys have mechanisms for protection of the mineralocorticoid receptor (MR) from these high levels of cortisol. We previously showed that the serum cortisol to cortisone ratio in these animals is low relative to that in human serum, suggesting that production of the MR protective enzyme, 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2), is increased in squirrel monkeys. Here, we directly evaluate whether increased production of 11beta-HSD2, which inactivates cortisol to cortisone, is a mechanism for protection of MR. In vitro assays showed that 11beta-HSD2 activity in squirrel monkey kidney microsomes was 3 to 7 times higher than that seen in kidney microsomes from pig or rabbit. 11beta-HSD2 protein detected by Western blot analysis was 4 to 9 times greater in squirrel monkey microsomes than in pig or rabbit microsomes. Comparison of the effect of expression of either human or squirrel monkey 11beta-HSD2 on MR transactivation activity showed similar inhibition of MR response to cortisol by both enzymes, indicating that the intrinsic activities of the human and squirrel monkey enzymes are similar. These findings suggest that one mechanism by which squirrel monkeys protect the MR from activation by high cortisol levels in the kidney is by upregulation of 11beta-HSD2 activity through increased production of the enzyme.     

Sporogenesis in Eusporangiate Ferns: II. Polyplastidic Meiosis in Ophioglossum (Ophioglossales)

Ophioglossum petiolatum . Unlike Angiopteris (Marattiales), which is monoplastidic, Ophioglossum undergoes polyplastidic meiosis like members of the fern-seed plant clade. The meiotic spindle is distinctly multipolar in origin and is consolidated into a bipolar spindle that is variously twisted and curved to accommodate the large number of chromosomes. Although a phragmoplast forms after first meiosis, no wall is deposited. Instead, an organelle band consisting of intermingled plastids and mitochondria is formed in the equatorial region between the dyad domains. Following second meiosis, a complex of phragmoplasts forms among sister and non-sister nuclei. Cell plates are deposited first between sister nuclei and then in the region of the organelle band resulting in a tetrad of spores each with a equal allotment of organelles. Received 30 January 2001/ Accepted in revised form 24 April 2001