Study of cellular changes induced by moderate cerebral ischemia achieved through internal carotid artery ligation

Reduced cerebral blood flow beyond the compensatory mechanisms leads to cerebral hypoxia. Hypoxia causes various lesions of neurons, glial cells and cerebral blood vessels, depending on its duration and intensity. In our study, we reduced cerebral blood flow in the experience animal on average by 30%, by right internal carotid artery ligation. Fifteen days after the onset of hypoxia, by histology and immunohistochemical studies, we identified neuronal, glial and vascular damage. Lesions of nerve and glial cells ranged from changes of cytoplasmic tinting with the development of "red neurons", to neuronal and glial cytolysis with areas of focal necrosis. Vascular lesions were represented by the collapse, fragmentation and discontinuity of capillaries, always associated with a marked perivascular edema.     

体外培养条件下兔脊柱运动节段髓核组织的变化

背景：椎间盘器官体外培养模型作为体内试验和细胞培养的联系,能够在原生基质中维持细胞活性,从而保留了重要的细胞与细胞及细胞与基质的相互作用。 目的：观察体外培养兔脊柱运动节段模型髓核组织的变化。 方法：将13只新西兰白兔处死后在无菌条件下取出脊柱运动节段50个,在高渗培养基中进行整体培养  (410 mOsm/kg),于培养前及培养后第3,7,14,21天,各取10个椎间盘分别进行苏木精-伊红染色、Ⅱ型胶原免疫组织化学、蛋白多糖含量和髓核细胞活力测定。 结果与结论：培养14 d苏木精-伊红显示椎间盘组织结构基本保持完整,21 d椎间盘组织形态学破坏;Ⅱ型胶原免疫组织化学染色强度14 d无显著差异(P > 0.05),21 d染色变浅,与之前各时间点相比有显著差异(P <   0.05);蛋白多糖PAS/AB染色7 d内强度无降低,14 d强度有所减弱,21 d染色强度进一步减弱;髓核细胞荧光检测21 d髓核细胞荧光强度减弱,细胞活性降低,与之前各时间点比较差异明显(P < 0.05)。结果表明,培养14 d兔脊柱运动节段椎间盘髓核组织退变不显著,培养21 d模型髓核退变明显,脊柱运动节段目前在14 d内可作为研究生物力学对椎间盘影响的体外实验模型。 中国组织工程研究杂志出版内容重点：组织构建;骨细胞;软骨细胞;细胞培养;成纤维细胞;血管内皮细胞;骨质疏松;组织工程      

The cause of a depressed glomerular filtration rate after an ischaemic insult: whole kidney and superficial nephron study in the dog

Twenty-four hours after 90 min clamping of the left renal artery in dogs, the glomerular filtration rate (GFR) was decreased in the whole kidney (0.34 ml.min^–1g KW^–1 [KW=Kidney weight] vs 0.64 in contralateral unclamped kidney) just as in the single nephron (SNGFR, 19.7 vs 51.8 nl.min^–1). Renal blood flow (RBF) did not change; single nephron glomerular blood flow (SNGBF) was decreased by 9% only. After injection of Lissamine green into the renal artery, brief diffuse tinting of the whole kidney surface was observed. Thereafter, patchy coloration — corresponding to passage of the dye through patent tubuli — took place in approximately one-quarter to one-third of the kidney surface. Micropuncture measurements were carried out in these areas.The values of hydraulic pressure in peritubular capillaries and proximal convolutions were not different from those found in controls; directly measured glomerular capillary pressure was decreased (48.7 vs 59.5 mmHg). The ultrafiltration coefficient(K _f) was significantly depressed (2.7 vs 3.8 mmHg.nl^–1.min). Total kidney and arteriolar resistances remained unchanged but afferent resistance (R _A) was elevated (11%) and efferent resistance (R _E) was lowered (23%) compared with those of controls. Ninetyseven percent of proximally microinjected ³H-inulin was recovered from the control kidney but only 85 % from the kidney rendered ischaemic. In conclusion, the typical findings at 24 h after 90 min ischaemia are low GFR and SNGFR with normal RBF and almost normal superficial SNGBF values. This phenomenon is mainly due to a decrease in K _f and a decrease in R _E with a simultaneous increase in R _A; back-leak through damaged tubuli seems to play only a minor role.     

The Beauty of the Network in the Brain and the Origin of the Mind in the Control of Behavior

Behavior is not adequately described as a stimulus-response process. It is initiated by the animal and is generated because of its expected outcome in the future. The outcome can be good or bad for the animal. The brain is in charge of the selection process. This is the basic function of the brain. Taking Drosophila as a study case, this paper discusses initiating activity, several examples of outcome expectations, trying out (the internal search for a suitable behavior), chaining of actions, and the functional roles of chance in action selection. It takes mental processes and states such as goals, intentions, feelings, memories, cognition, and attention as higher levels of behavioral control that have their origin in biological evolution.     

Counterpointing the functional role of the forebrain and of the brainstem in the control of the sleep-waking system

This paper reviews the lifetime contributions of the author to the field of sleep-wakefulness (S-W), reinterprets results of the early studies, and suggests new conclusions and perspectives. Long-term cats with mesencephalic transection show behavioral/polygraphic rapid eye movement sleep (REMS), including the typical oculo-pupillary behavior, even when the section is performed in kittens prior to S-W maturation. REMS can be induced as a reflex. Typical non-rapid eye movement S (NREMS) is absent and full W/arousal is present only after a precollicular section. The isolated forebrain (IF) rostral to the transection exhibits all features of W/arousal and NREMS [with electroencephalographic (EEG) spindles and delta waves], arousal to olfactory stimuli, and including the appropriate oculo-pupillary behaviors. These features also mature normally after neonatal transection. REMS is absent from the IF. After deprivation there is NREMS pressure and rebound in the IF, but the decerebrate cat only shows pressure for REMS. Most IF reactions to pharmacologic agents are within expectations, except for the tolerance/withdrawal effects of long-term morphine use which are absent. In contrast, these effects are supported by the brainstem (i.e. seen in the decerebrate cat). In cats with ablation of the telencephalon, or diencephalic cats, delta waves are absent in the thalamus. EEG thalamic spindle waves are seen triggering S for only 4-5 days after ablation. Therefore, true NREMS is absent in chronic diencephalic cats although pre- and postsomniac behaviors persist. These animals are hyperactive and show a pronounced, permanent insomnia; however, a low dose of barbiturate triggers a dramatic REMS/atypical NREMS rebound. Cats without the thalamus (athalamic cats), initially show a dissociation between behavioral hyperactivity/insomnia and the neocortical EEG, which for 15-20 days exhibits only delta and slower oscillations. Fast, low-voltage W rhythms appear later on, first during REMS, but spindle waves and S postures are absent from the start, such that these cats also display only atypical NREMS. Athalamic cats also show barbiturate-sensitive insomnia. Cats with ablation of the frontal cortices or the caudate nuclei remain permanently hyperactive. They also show a mild, but significant hyposomnia, which is permanent in afrontal cats, but lasts for about a month in acaudates. The polygraphic/behavioral features of their S-W states remain normal. We conclude and propose that: (a) the control of the S-W system is highly complex and distributed, but is organized hierarchically in a well-defined rostro-caudal manner; the rostral-most or highest level (telencephalon), is the most functionally complex/adaptative and regulates the lower levels; the diencephalic/basal forebrain, or middle level, has a pivotal role in inducing switching between S and W and in coordinating the lowest (brainstem) and highest levels; (b) W can occur independently in both the forebrain and brainstem, but true NREMS- and REMS-generating mechanisms exist exclusively in the forebrain and brainstem, respectively; (c) forebrain and brainstem S-W processes can operate independently from each other and are preprogrammed at birth; this helps understanding normal and abnormal polygraphic/behavioral dissociations in humans and normal dissociations/splitting in aquatic mammals; (d) NREMS homeostasis is present in the IF, but only REMS pressure after deprivation persists in the decerebrate cat; (e) the thalamus engages in both NREMS and W; (f) insomnia in diencephalic cats is the result of an imbalance between antagonistic W- and S-promoting cellular groups in the ventral brain (normally modulated by the telencephalon); (g) the EEG waves, which are signature for each S-W state, appear to truly drive the concomitant behaviors, e.g. a hypothetical human IF could alternate between behavioral NREMS and W/arousal/awareness; (h) a role for REMS is to keep the individual sleeping at the end of the self-limiting NREMS periods. The need for accelerating research on telencephaling NREMS periods. The need for accelerating research on telencephalic S-W processes and downstream control of the lower S-W system levels is emphasized.     

On the musculature of the gastro-intestinal tract of the guinea-pig

Summary The small intestine, caecum, colon and part of the stomach of guinea-pigs were studied by light microscopy, using semithin sections of plastic embedded specimens. The muscular coat is thicker in the duodenum than in the rest of the small intestine. The ratio between longitudinal and circular muscle is 1:4.6 in the duodenum and it increases regularly along the small intestine, to reach 1:2 in the terminal ileum. In the caecum, shape and sectional area of the muscle tissue were analyzed along the full length of the taeniae. In the caecal circular muscle there is a characteristic change in the arrangement of the muscle bundles from the regions in the centre of the haustrations to the regions of the grooves between haustrations or to those lying beneath a taenia. The functional significance of the taeniae is discussed in terms of an arrangement allowing reduction of the lumen of the organ (which at the level of the grooves between haustrations acquires a triangular outline) more efficiently than if the longitudinal musculature were spread over the entire surface of the organ. Haustrations are present also on one side of the wall of the ascending colon where there is no longitudinal muscle layer. In the descending colon the structure of the wall is examined in different functional states, namely in the regions between fecal pellets (constricted regions) and in the regions around a fecal pellet (moderately distended regions). The musculature increases considerably in thickness in the constricted regions (both muscle layers being actively contracted), while the mucosa and submucosa are thrown into prominent longitudinal folds. These folds produce occlusion of the lumen when the circular muscle has shortened by about 50%.     

Transformations of the retinal topography along the visual pathway of the chicken

Summary It is still unclear how the retinotectal map of the chick is formed during development. In particular, it is not yet known whether or not the organization of fibres plays a role in the formation of this map. In order to contribute to the solution of this problem, we analysed the representation of the retinal topography at closely spaced intervals along the fibre pathway. We injected HRP into various sites of the tectal surface and traced the labelled fibre bundles back to the retina. The retinal topography was reconstructed at ten different levels, i.e. in the retina, the optic nerve head, the middle of the optic nerve, the chiasm (three levels), the optic tract (three levels), and the optic tectum. We obtained the following results: (1) The labelled fibre bundles as well as the fields of labelled retinal ganglion cells were always well delimited and coherent. (2) The reconstructions show that transformations of the retinal topography occur in the fibre pathway. The first and most important transformation is found in the optic nerve head where the retinal image is mirrored across an axis extending from dorsotemporal to ventronasal retina. In addition, the retinal representation is split in its temporal periphery. Thus, central and centrotemporal fibres are no longer in the centre of the image but close to the dorsal border of the nerve. Peripheral fibres are found along the medial, ventral and lateral circumference of the nerve. In the optic tract a second transformation occurs. The retinal topography is rotated clockwise by about 90 degrees and flattened to a band. The flattening is accompanied by a segregation of fibre bundles so that eventually central and centrotemporal retinal fibres are located centrally, ventral fibres dorsally and dorsal retinal fibres ventrally in the tract. By these two transformations an organization of fibres is produced in the optic tract which can be projected onto the tectal surface without major changes given that dorsal and ventral fibres remain in their relative positions, and that deep lying fibres project to the rostral and central tectum, superficial fibres to the caudal tectum.The transformations which we have observed follow specific rules and thus maintain order in the pathway although retinotopy is lost. In conjunction with our earlier studies on the development of the retinotectal system we conclude that fibres are laid down in a chronotopic order. The transformations take place under particular structural constraints. Thus, an organization of fibres is provided in the optic tract which results in a retinotopic map when projected onto the tectal surface. This is stated for the order of magnitude of fibre bundles as investigated in this study. At the level of individual fibres additional factors may play an important role.     

On the inadequacy of the concept of disease

A framework for a critical examniation of the disease concept is presented. The human organism is regarded as a complex system upon which certain hierarchies are imposed. The cell is regarded in this framework as the lowest hierarchy. Cells are aggregated into tissues and tissues into organs. Organs are assembled into organ systems constituting the human organism. The elementary indivisible unit in each hierarchy is called the HOLON. When viewed from the hierarchy below it encompasses a continuum. The holon is defined by its attributes. Its STATE represents the magnitudes of its attributes. The state of the organism is defined by the states of its holons. For each attribute a criterion level (or state) defines its ILLNESS STATE. ILLNESS is defined by the set of attributes crossing the criterion level. These attributes are divided into two two sets: Attributes requiring treatment by the physician and those not requiring intervention by him. The first is defined as DISEASE, while the second as the VIS MEDICATRIX NATURAE. THERAPY is the restoration of “ill” attributes below their criterion levels. The process of selecting the DISEASE attribute set from all organismic attributes is called DIAGNOSIS. The correctness of a diagnosis is testable by treatment results. A successful treatment corroborates the diagnosis and vice versa. Since an intractable disease is also untreatable, its diagnosis is not testable (or falsifiable) in Popper's sense. The framework provides also means to test the relevancy of cancer theories to human cancer.     

团体心理辅导对贫困大学生自信心干预的探讨

目的探讨团体心理辅导对提高贫困大学生自信心的效果。方法经过宣传、招募、面谈、筛选，采用自行编制的团体心理辅导方案，对10名贫困大学生（非控制组）进行为期6周的团体训练，对实验组进行前测后测，并建立控制组（控制组）。结果①实验组后测在ASLEC等量表得分与前测均有显著性差异（P〈0．01），而与控制组无显著性差异。②实验组后测的主观评定分显著性的高于前测（P〈0．01），而与控制组无显著性差异。结论①团体心理辅导可以有效地帮助贫困大学生克服自卑、建立自信。②团体心理辅导应该考虑长效影响的评估。     

On the development of the lymphoid follicles of the bursa of fabricius

The structural features of the development of the bursa of Fabricius in white Leghom chick embryos are depicted at carefully timed intervals during embryogenesis, with emphasis on the sequence of events between the ninth and twelfth days of incubation. The direction and character of the migration of lymphoid cell precursors and granulocytes from the intravascular space to intraepithelial sites, where the formation of the primitive lymphoepithelial nodule takes place, is demonstrated. The mechanism of the mode of migration of these cells through the stromal epithelial interface is described and illustrated with electron micrographs and their role in the development of the primitive lymphoid follicles is described and discussed.     

A study of the anatomic features of the duct of the urachus

Abstract The urachus is an embryonic remnant resulting from involution of the allantoic duct and the ventral cloaca. Attaching the bladder dome to the umbilicus, this duct becomes progressively obliterated during fetal life. It may subsequently persist as different variants after birth, some regarded as normal, others as pathologic, due to incomplete closure. Six pediatric cases are reported here, and the literature on the embryology and anatomic basis of the duct is discussed. The urachus is present in nearly 100% of children at birth, with several possible shapes tubular, fusiform or funnel. It gradually regresses and is found in only a third of adults. Its length varies from 1 to 15 cm. In our series 6 patients showed defective closure of the duct, including 3 with complete patency, 1 cyst, 1 diverticulum and 1 external sinus. Although rare, congenital pathology of the urachus requires a sound knowledge of the anatomy and embryology to distinguish normal forms from those subject to complications. It should be suspected with any lesion in the umbilical region and the appropriate treatment instituted.     

肺表面活性物质聚集性研究

显微镜下观察PS制剂是由液泡球状和液泡棒状聚集物组成.浓度较低的PS制剂溶液中聚集物数量较少;浓度较大的液体内聚集物数量多,放置在载玻片上的PS溶液经过一段时间干涸后,聚集物内外的水分被蒸发,形成板层状聚集物,经分析本文认为此聚集物可能是卵磷脂的聚集物,或表面活性物质胶团的聚集物,并给出其可能的结构示意图.     

On the significance of the fibrinolytic system of the blood

Summary Subject to a study in experiments on dogs (involving intravenous administration of nicotinic acid and thromboplastin, blood loss) and in observations of patients (operative interventions, atherosclerosis, thromboembolic disease, etc.) were interrelationships between the blood coagulation, fibrinogen concentration, fibrinolytic and fibrinogenolytic activity. The blood of healthy individuals and dogs showed fibrinolytic activity to be present regularly. Fibrinogenolytic activity, on the other hand, was absent. In stress conditions (surgical intervention, blood loss, nicotinic acid administration) the blood coagulation was accelerated with blood fibrinolytic activity increasing at the same time (no fíbrinogenolysis was present). Intensified fibrinolytic activity of the blood is a normal protective body reaction, occurring with acceleration of blood coagulation. This regularity is disturbed in pathological conditions. Association of accelerated blood coagulation with diminished fibrinolysis (atherosclerosis, thromboembolic disease) creates favorable conditions for thrombosis. There is no direct relationship between blood fibrinogen concentration and its fibrinolytic activity. This is explained by the fact that, as a rule, activation of fibrinolytic system in the body leads to the intensification of its fibrinolytic properties, but not of fibrinogenolytic ones.(Presented by Active Member of the AMN SSSR A. V. Lebedinskii) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 54, No. 9, pp. 35–39, September, 1962     

Model studies of the effects of the thoracic pressure on the circulation

Two models of the cardiovascular system subjected to changes in intrathoracic pressure (ITP) are used to simulate the response to normal and positive pressure ventilation and the Mueller maneuver. The first model, based on our earlier model for cardiopulmonary resuscitation and cardiac assist by ITP variations, is based on lumped parameter representation of the cardiovascular system with two ventricles which function based on the time-varying elastance concept using their transmural pressures as the load. The ITP is assumed to be equally distributed in the thoracic cavity and equally affecting all cardiovascular structures within the chest. The model shows that a decrease in ITP is associated with an initial decrease in aortic pressure and flow and an increase in left ventricular end-diastolic and end-systolic volumes. A transient decrease in left ventricular volume which was suggested to occur by a few studies cannot be predicted based on this model. Such a decrease in left ventricular volume can be only predicted when a pericardial constraint is included, as done in the second model. Positive pressure interventions are associated with decreased heart volumes and cardiac output which is primarily a “preload” effect. In general the model reasonably predicts the hemodynamics as a function of the ITP changes and may be used as a tool to investigate the response of the cardiovascular system to various ITP interventions.     

Characterization of the brown pigment of the mucosa of the urinary tract

Summary The brownish discoloration of the mucosa of the urinary tract which is present in 10–42% of the patients with chronic abuse of analgesics containing phenacetin is, like the discoloration of liver, skin and cartilage, due to lipids similar in type to those in the lipid component of lipofuscin. Offprint requests to: M.J. Mihatsch at the above address     

Overview of the Current State of the Epidemic

At the end of 2011, about half of the 34.0 million [31.4–35.9 million] people living with HIV infection knew their HIV status. With large regional variations, an estimated 0.8 % of all adults aged 15 to 49 years have HIV infection and HIV subtype diversity is increasing. Although HIV incidence has declined in 39 countries, it is stable or increasing in others. HIV prevalence continues to rise as antiretroviral treatment scale-up results in fewer HIV-related deaths while new infections continue to occur. Increased treatment uptake is likely reducing HIV transmission in countries with large mortality declines. Key populations, including sex workers, men who have sex with men, transgender people, people who inject drugs and young women in high prevalence settings require effective prevention programs urgently. Correcting mismatches in resource allocation and reducing community viral load will accelerate incidence declines and affect future epidemic trends, if concerted action is taken now.     

Significance of the output of the right and left ventricles in the formation of the IJ waves of the ballistocardiogram

Summary Ballistocardiography applied to patients with patent ductus arteriosus or atrial septal defect showed an increased IJ wave in cases where the left systolic volume was increased, an effect which was independent of the right ventricular output. It is concluded that it is the activity of the left ventricle which is of principal importance in the genesis of the IJ wave.(Presented by Active Member AMN SSSR A. A. Vishnevskii) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 57, No. 4, pp. 8–11, April, 1964     

A model of the mechanics of the left ventricle

The relation between cardiac muscle mechanics and left ventricular (LV) pump function is simulated by a mathematical model. In the following article special attention is paid to the relation between LV pressure and LV volume on the one hand and the transmural distribution of sarcomere length and fiber stress on the other. The LV is simulated by a thick-walled cylinder composed of 8 concentric shells. The myocardial material is assumed to be anisotropic. The orientation and sequential activation of the muscle fibers across the LV wall are considered per shell. Twisting of the base with respect to the apex around the axis of the LV is simulated by rotation of the upper cross-sectional surface of the cylinder with respect to the lower one aroud the axis of the cylinder. The model reveals that twisting of the LV is an important means to equalize transmural differences in sarcomere shortening and end-systolic fiber stress. When torsion is allowed, transmural differences in sarcomere shortening and end-systolic fiber stress are less than 18% and 16%, respectively. When torsion is prevented as in most of the models of LV-mechanics described in literature, these transmural differences increase up to 32% and 42%, respectively. Supported by the Foundation for Medical Research FUNGO, which is subsidized by the Netherlands organization for the Advancement of Pure Research.     

Effect of the state of sleep and wakefulness on transmission of the afferent signal through the posterior ventral nucleus of the thalamus

The effect of the state of sleep and wakefulness on transmission of afferent stimuli and subsequent inhibitory processes in the posterior ventral nucleus of the thalamus was studied in chronic experiments on unanesthetized cats. In a drowsy state and in a state of superificial sleep stimulus transmission is reduced, whereas in an active state (during the arousal reaction, movement, eating, etc.) it is increased. In paradoxical sleep stimulus transmission is at the same level as in a state of quiet wakefulness. In a drowsy state and in the first phase of sleep marked fluctuation of transmission is observed. The level of stimulus transmission is most stable in active states. The intensity of the after-inhibition following transmission of the afferent signal depends on the level of anesthesia, of wakefulness, and of natural sleep. Processes following transmission of the afferent stimulus in the posterior ventral nucleus of the thalamus during barbiturate anesthesia differ radically from those in the unanesthetized animal. After-inhibition, so characteristic of anesthesia, is manifested in the drowsy state only to a slight degree, and in the waking state it is not exhibited at all.P. K. Anokhin Institute of Normal Physiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 387–390, April, 1977.     

Examination of the reliability of the portable calorimeter

1. The present study was performed in order to determine the reliability of the portable calorimeter. 2. Resting energy expenditure (REE) was measured by two different apparatuses: one was the typical gas analyser, the other was the portable calorimeter. 3. Although there are differences among individuals, unless the subject has been exposed to severe physical activity prior to the measurement, a suitable resting time prior to the measurement of resting metabolic rate is 10 min. 4. For the measurement of resting metabolic rate, fluctuations in respiratory quotient (RQ) are extremely small; there is greater fluctuation due to variations in respiration. Therefore, for the screening of energy consumption, the use of a fixed value for RQ is sufficient when measuring only oxygen uptake. 5. Respiratory fluctuations vary from person to person and it is not possible to make stable measurements in 1 or 2 min. Therefore, a suitable measurement time for resting metabolic rate is from 3 to approximately 6 min. 6. The results indicate that this portable calorimeter is a useful apparatus for measuring REE in the field.