Objective To evaluate the indications and intraoperative management of nephron-spar- ing surgery (NSS) for renal cell carcinoma (RCC).Methods A total of 53 patients (32 men and 21 women;age range,21 -76 years) with unilateral RCC and a normal contralateral kidney underwent NSS.The disease course ranged from 1 week to 13 months.The unilateral RCCs were detected by B-uhrasonography. Partial nephrectomy was performed on 38 cases of polar RCC and wedge nephrectomy was performed on 15 cases of central RCC.Both renal vein and artery were blocked for 10 - 15 min,and unclamped for 1 -2 min if necessary.The resections were finished within 7 -21 min (mean,12 min).No inosine and regional hypo- thermia were used during operation.Absorbable hemostatic gauze and terylene flake were used to suture renal wound surface.After operation all patients were treated with interferon hypodermic injection of 5 000 000 U every other day for 3 months.Results The diagnosis of RCC with negative cutting margin was confirmed by pathological examination in all patients.The greatest dimension of the renal cancers were＜4 cm except for one of 6 cm.The clinical stage was T_1N_0M_0 in all patients.During the follow-up of 6 -48 months,all pa- tients were alive without recurrence and had normal renal function.Conclusions NSS can be rapidly per- formed for T_1 stage renal cancer＜4 cm or single clearly localized cancer＞4 cm in diameter.The follow-up results are satisfactory.

BACKGROUNDAscorbic acid (AA) represents one of the most important enzyme co-factors, antioxidants and neuromodulators and plays an important role in the cerebral system. Increasing evidence has suggested that AA could treat certain kinds of vertigo diseases such as Meniere's disease. To elucidate the neurochemical functions associated with AA in vertigo, the change of extracellular AA in the brain cortex following caloric vestibular stimulation (CVS) was evaluated.

METHODSAn on-line electrochemical detection was coupled with in vivo microdialysis to continuously monitor the change of extracellular AA in the primary somatosensory (SI) area of guinea pigs following a caloric vestibular stimulation. Sixteen guinea pigs were divided into three groups, i.e., experimental group with irrigation of the ear canal with ice water (0 degrees C) (n = 8), and two control groups, one with irrigation of the ear canal with warm water (38 degrees C) (n = 4) and the other with irrigation of the auricle with ice water (n = 4).

RESULTSIn the experimental group, the ice water irrigation of the left external ear canal induced a horizontal nystagmus towards the right side lasting about 45 seconds. No nystagmus was induced by warm water irrigation of the external ear canal or by ice water irrigation of the auricle. The extracellular AA concentration significantly increased following the ice water vestibular stimulation, reaching a maximum of (130 +/- 20)% (n = 8) of the basal dialysate level (2.61 +/- 0.92) micromol/L (n = 8), lasting at least for an hour. AA level did not change distinctly after the irrigation of the left external ear canal with warm water or the irrigation of the auricle with ice water.

CONCLUSIONSThe concentration of extracellular AA in the brain cortex of the SI area increased following the ice water vestibular stimulation. This demonstration may be useful for the investigation of the neurochemical processes associated with AA in the process of vertigo.

Animals ; Ascorbic Acid ; analysis ; Cerebral Cortex ; metabolism ; Electrochemistry ; methods ; Extracellular Space ; metabolism ; Guinea Pigs ; Ice ; Male ; Microdialysis ; methods ; Physical Stimulation ; methods ; Vestibule, Labyrinth ; physiopathology

BACKGROUNDAscorbic acid has important antioxidant properties, and may play a role in the protective effects of ischemic preconditioning on later ischemia-reperfusion. Herein, we examined the role of endogenous extracellular ascorbic acid in ischemic preconditioning in the kidney.

METHODSWe developed a solitary rabbit kidney model where animals received ischemia-reperfusion only (ischemia-reperfusion group, n = 15) or ischemic preconditioning followed by ischemia-reperfusion (ischemic preconditioning group, n = 15). Ischemia-reperfusion was induced by occluding and loosening of the renal pedicle. The process of ischemic preconditioning included 15-minute brief ischemia and 10-minute reperfusion. In vivo microdialysis coupled with online electrochemical detection was used to determine levels of endogenous extracellular ascorbic acid in both groups. The extent of tissue damage was determined in kidney sections stained with hematoxylin and eosin. Serum creatinine and urea nitrogen were also detected to assess renal function.

RESULTSDuring ischemia-reperfusion, the extracellular ascorbic acid concentration during ischemia increased rapidly to the peak level ((130.01 +/- 9.98)%), and then decreased slowly to near basal levels. Similar changes were observed during reperfusion (peak level, (126.78 +/- 18.24)%). In the ischemic preconditioning group there was a similar pattern of extracellular ascorbic acid concentration during ischemic preconditioning. However, the ascorbic acid level was significantly lower during the ischemia and early reperfusion stage compared to the ischemia-reperfusion group. Additionally, the extent of glomerular ischemic collapse, tubular dilation, tubular denudation, and loss of brush border were markedly attenuated in the ischemic preconditioning group. Levels of serum creatinine and urea nitrogen were also decreased significantly in the ischemic preconditioning group.

CONCLUSIONSIschemic preconditioning may protect renal tissue against ischemia-reperfusion injury via use of extracellular ascorbic acid. In vivo microdialysis coupled with online electrochemical detection is effective for continuous monitoring extracellular ascorbic acid in the renal cortex.

Animals ; Ascorbic Acid ; metabolism ; Disease Models, Animal ; Ischemic Preconditioning ; methods ; Kidney ; metabolism ; pathology ; Rabbits ; Reperfusion Injury ; prevention & control

Acute traumatic spinal cord injury (SCI) represents one of the most devastating injuries that afflict the human body. Ascorbic acid ( AA) plays an important role in mammalian central nervous system, especially in SCI. In this study, the change of AA concentration after SCI was investigated by using an on-line electrochemical method integrated with in vivo microdialysis. A microdialysis probe (2 mm in length) was implanted into the spinal cord of an anesthetized rat (Thoracic-10). Microdialysis perfusate (2 μL/ min) was collected in the sample loop of an on-line injector for direct injection onto a glassy carbon electrode which was modified with the heat-treated single-walled carbon nanotubes (SWNTs). Normal ascorbic acid concentration in the extracellular fluids of spinal cords was (26. 17 ± 1. 25) μmol/ L (n =8). The experimental spinal cord injury, induced by a lesion at T-10, significantly increased the extracellular ascorbic acid levels to (53. 24± 1. 95) μmol/ L (n =8). This study provides the experimental evidence on the essential roles of ascorbic acid in spinal cord injuries.

Objective:Based on the modified ultracentrifugation method, the outer membrane vesicles (OMV) secreted by Klebsiella pneumoniae were rapidly separated, identified and quantified. Methods:Standard strains of classic Klebsiella Pneumoniae (cKP) purchased from the Clinical Laboratory Center of the National Health Commission, and hypervirulent Klebsiella pneumoniae (hvKP) which was donated by Taiwan University were cultured in M9 basal media for 9 hours, and the OMV were extracted by modified ultracentrifugation. The shape and size of OMV were identified by transmission electron microscopy (TEM), relative quantification by Stewart phospholipids analysis method. Two groups were compared using independent samples t test. Results:It was observed under the TEM that most of the OMV secreted by cKP and hvKP showed spherical vesicle structure and a small part were irregular. The diameter of OMV ranged from 20 to 250 nm, multiple vesicles could be seen in clusters. Relative quantification found that the number of OMV secreted by hvKP were more than cKP ( P<0.05). Conclusions:This study successfully achieved the extraction, identification and quantification of OMV from Klebsiella pneumoniae through the modified ultracentrifugation method, which provided a foundation for further study about the function and mechanism of OMV, and also provided new ideas for the treatment of bacteria. Based on the ultracentrifugation method, the OMV secreted by Klebsiella pneumoniae were rapidly separated and extracted, then identified and quantified.

BACKGROUNDAnatomic and electrophysiological studies have revealed that the neurons located in the media vestibular nuclei (MVN) receive most of the sensory vestibular input coming from the ipsilateral labyrinth and the responses of MVN neurons to caloric stimulation directly reflect changes in primary vestibular afferent activity. The aim of this study was to clarify the intrinsic characteristics of serotonin (5-hydroxytryptamine, 5-HT) release in the MVN during the period of vertigo induced by caloric stimulation.

METHODSWe used an in vivo microdialysis technique to examine the effects of caloric stimulation on the serotoninergic system in MVN. Twenty four guinea pigs were randomly divided into the groups of irrigation of the ear canal with hot water (n = 6), ice water (n = 6) and 37 degrees C water (n = 4), and the groups of irrigation of the auricle with hot water (n = 4) and ice water (n = 4), according to different caloric vestibular stimulation. We examined the animal's caloric nystagmus with a two-channel electronystagmographic recorder (ENG), and meanwhile examine serotonin (5-hydroxytryptamine, 5-HT) level in the MVN with microdialysis technique after caloric stimulation.

RESULTSIn the caloric test the hot water (44 degrees C) irrigation of the right external auditory canal induced horizontal nystagmus towards the right side lasting about 60 seconds and the ice water irrigation of the right external auditory canal induced it towards the left side lasting for about 90 seconds. No nystagmus was induced by 37 degrees C water irrigation of the external ear canal. Therefore, it was used as a negative control stimulation to the middle ear. The MVN 5-HT levels significantly increased in the first 5-minute collecting interval and increased to 254% and 189% of the control group in the second collecting interval in response to caloric vestibular stimulation with ice water and hot water respectively. The serotonin release was not distinctly changed by the irrigation of the auricle with ice water or hot water.

CONCLUSIONSNeither somato-sensory stimulation of the middle ear nor nonspecific cold or hot stress affects the serotonin release. The rise of 5-HT in MVN may be involved in the mechanism of vertigo induced by caloric stimulation.

Animals ; Caloric Tests ; Guinea Pigs ; Microdialysis ; Serotonin ; secretion ; Vertigo ; etiology ; Vestibular Nuclei ; pathology

OBJECTIVETo analyze expression characteristics of human skin epidermal stem cell at different developmental stages, and to explore its biological significance.

METHODSHealth skin samples from 28-32 w fetuses (F group), 4-12 y children (C group), and 35-55 y adult (A group) were harvested, with 10 cases in each group. Epidermis were separated using trypsin digestion and EDTA, and human epidermal stem cells were isolated and purified with type IV collagen attachment method. The monoclonal antibody of integrin beta1 and keratin 19 were used for detection and identification of epidermal stem cells by immunohistochemical staining. Total RNA was extracted from above cells by Trizol one-step method, and were detected by formaldehyde denaturing agarose gel electrophoresis. Probes were prepared and hybridized into cDNA microarray for scanning fluorescent signals and analysis of images, with two-fold differential expression value for screening. Significantly up/down-regulated genes were selected for verification by real time RT-PCR.

RESULTSBy comparing expression profile between A and C groups, a total of 1808 genes with differential expression were detected, including 1089 up-regulated genes and 719 down-regulated genes, and they were classified into 128 categories. Among them, 1462 genes were known (found in GeneBank), 346 genes were unknown. A total of 4534 genes with differential expression were detected between C and F groups, in which 1783 genes were up-regulated and 2751 genes were down-regulated, and they were classified into 216 categories. Among them, 3577 genes were known (found in GeneBank), and 957 genes were unknown. There were 1104 genes with differential expression consistently detected in F, C and A groups, which were classified into 32 categories according to gene function. Among them, 94 genes were consistently up-regulated and 75 genes consistently down-regulated. Test results of real time RT-PCR were in accordance with above-mentioned results.

CONCLUSIONSGene expression profiles of epidermal stem cells cultured in vitro, harvested from fetuses, children, and adult, exhibit obvious difference. This may be closely related to different stages of proliferation and differentiation of human epidermal stem cell and self-repair ability of wound at different developmental stages.

Adult ; Cell Differentiation ; Child ; Child, Preschool ; Epidermis ; cytology ; growth & development ; Epithelial Cells ; cytology ; Fetus ; cytology ; Gene Expression Profiling ; Gene Expression Regulation, Developmental ; Humans ; Middle Aged ; Oligonucleotide Array Sequence Analysis ; methods ; Stem Cells ; cytology ; Transcriptome

OBJECTIVETo understand the status of knowledge and behavior of drug use among urban and rural residents in 5 provinces in China to suggest priority intervention strategies and measures for drug use health education.

METHODSFrom March to May of 2011, 6159 urban and rural residents were selected from Beijing, Liaoning, Zhejiang, Yunnan, Shaanxi provinces by the multistage stratified sampling method and were investigated by the questionnaires on drug use knowledge and behavior.

RESULTSThe residents' average awareness rate for 11 pieces of basic drug use information was 48.3% (32,750/67,749). The residents' average awareness rate in the rural (40.3%, 9189/22 792) was lower than that in metropolitan (51.9%, 11 483/22 110) and small and middle-sized cities (52.9%, 12,078/22,847) and the differences had statistical significance (χ2=889.30, P<0.01). Overall, 77.0% (4742/6159) of residents purchased drug according to the doctors' prescription; 36.9% (2271/6159) of residents bought by their experiences; 33.3% (2049/6159) of residents did not know whether they had bought faked drugs; 32.7% (2016/6159) of residents did not read instructions carefully before using drug; 83.4% (5134/6159) of residents stored drugs in their house and only 29.2% (1798/6159) of residents would check up expired drugs regularly; 59.6% (3673/6159) of residents changed drug by themselves after suspected adverse reaction of drugs.

CONCLUSIONChinese urban and rural residents' knowledge level of drug use is inadequate and drug use behaviors are not optimistic. Drug use health education should be enhanced among urban and rural residents.

China ; Drug Therapy ; Health Education ; Health Knowledge, Attitudes, Practice ; Humans ; Prescription Drugs ; Surveys and Questionnaires

Sleep is an instinctive behavior alternating awakening state, sleep entails many active processes occurring at the cellular, circuit and organismal levels. The function of sleep is to restore cellular energy, enhance immunity, promote growth and development, consolidate learning and memory to ensure normal life activities. However, with the increasing of social pressure involved in work and life, the incidence of sleep disorders (SD) is increasing year by year. In the short term, sleep disorders lead to impaired memory and attention; in the longer term, it produces neurological dysfunction or even death. There are many ways to directly or indirectly contribute to sleep disorder and keep the hormones, including pharmacological alternative treatments, light therapy and stimulus control therapy. Exercise is also an effective and healthy therapeutic strategy for improving sleep. The intensities, time periods, and different types of exercise have different health benefits for sleep, which can be found through indicators such as sleep quality, sleep efficiency and total sleep time. So it is more and more important to analyze the mechanism and find effective regulation targets during sleep disorder through exercise. Dopamine (DA) is an important neurotransmitter in the nervous system, which not only participates in action initiation, movement regulation and emotion regulation, but also plays a key role in the steady-state remodeling of sleep-awakening state transition. Appreciable evidence shows that sleep disorder on humans and rodents evokes anomalies in the dopaminergic signaling, which are also implicated in the development of psychiatric illnesses such as schizophrenia or substance abuse. Experiments have shown that DA in different neural pathways plays different regulatory roles in sleep behavior, we found that increasing evidence from rodent studies revealed a role for ventral tegmental area DA neurons in regulating sleep-wake patterns. DA signal transduction and neurotransmitter release patterns have complex interactions with behavioral regulation. In addition, experiments have shown that exercise causes changes in DA homeostasis in the brain, which may regulate sleep through different mechanisms, including cAMP response element binding protein signal transduction, changes in the circadian rhythm of biological clock genes, and interactions with endogenous substances such as adenosine, which affect neuronal structure and play a neuroprotective role. This review aims to introduce the regulatory effects of exercise on sleep disorder, especially the regulatory mechanism of DA in this process. The analysis of intracerebral DA signals also requires support from neurophysiological and chemical techniques. Our laboratory has established and developed an in vivo brain neurochemical analysis platform, which provides support for future research on the regulation of sleep-wake cycles by movement. We hope it can provide theoretical reference for the formulation of exercise prescription for clinical sleep disorder and give some advice to the combined intervention of drugs and exercise.

As China accelerates its efforts in deep space exploration and long-duration space missions, including the operationalization of the Tiangong Space Station and the development of manned lunar missions, safeguarding astronauts’ physiological and cognitive functions under extreme space conditions becomes a pressing scientific imperative. Among the multifactorial stressors of spaceflight, microgravity emerges as a particularly potent disruptor of neurobehavioral homeostasis. Dopamine (DA) plays a central role in regulating behavior under space microgravity by influencing reward processing, motivation, executive function and sensorimotor integration. Changes in gravity disrupt dopaminergic signaling at multiple levels, leading to impairments in motor coordination, cognitive flexibility, and emotional stability. Microgravity exposure induces a cascade of neurobiological changes that challenge dopaminergic stability at multiple levels: from the transcriptional regulation of DA synthesis enzymes and the excitability of DA neurons, to receptor distribution dynamics and the efficiency of downstream signaling pathways. These changes involve downregulation of tyrosine hydroxylase in the substantia nigra, reduced phosphorylation of DA receptors, and alterations in vesicular monoamine transporter expression, all of which compromise synaptic DA availability. Experimental findings from space analog studies and simulated microgravity models suggest that gravitational unloading alters striatal and mesocorticolimbic DA circuitry, resulting in diminished motor coordination, impaired vestibular compensation, and decreased cognitive flexibility. These alterations not only compromise astronauts’ operational performance but also elevate the risk of mood disturbances and motivational deficits during prolonged missions. The review systematically synthesizes current findings across multiple domains: molecular neurobiology, behavioral neuroscience, and gravitational physiology. It highlights that maintaining DA homeostasis is pivotal in preserving neuroplasticity, particularly within brain regions critical to adaptation, such as the basal ganglia, prefrontal cortex, and cerebellum. The paper also discusses the dual-edged nature of DA plasticity: while adaptive remodeling of synapses and receptor sensitivity can serve as compensatory mechanisms under stress, chronic dopaminergic imbalance may lead to maladaptive outcomes, such as cognitive rigidity and motor dysregulation. Furthermore, we propose a conceptual framework that integrates homeostatic neuroregulation with the demands of space environmental adaptation. By drawing from interdisciplinary research, the review underscores the potential of multiple intervention strategies including pharmacological treatment, nutritional support, neural stimulation techniques, and most importantly, structured physical exercise. Recent rodent studies demonstrate that treadmill exercise upregulates DA transporter expression in the dorsal striatum, enhances tyrosine hydroxylase activity, and increases DA release during cognitive tasks, indicating both protective and restorative effects on dopaminergic networks. Thus, exercise is highlighted as a key approach because of its sustained effects on DA production, receptor function, and brain plasticity, making it a strong candidate for developing effective measures to support astronauts in maintaining cognitive and emotional stability during space missions. In conclusion, the paper not only underscores the centrality of DA homeostasis in space neuroscience but also reflects the authors’ broader academic viewpoint: understanding the neurochemical substrates of behavior under microgravity is fundamental to both space health and terrestrial neuroscience. By bridging basic neurobiology with applied space medicine, this work contributes to the emerging field of gravitational neurobiology and provides a foundation for future research into individualized performance optimization in extreme environments.