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1.
Primary dissociated cultures of rhombencephalon were prepared from 5-9-week-old human fetuses. Half of some cultures were treated by two non-competitive N-methyl-D-aspartate antagonists, namely 1-(2-thienyl)cyclohexylpiperidine (TCP) and cis-Pip/Mel-[1-(2-thienyl)-2-methyl-cyclohexyl]piperidine (GK11) in negative enantiomeric form, which enhance the survival of human fetal central nervous system cells in culture. At different days in vitro, the treated and the control cultures were processed for immunocytochemical detection of serotonin-containing neurons which were studied by morphological and morphometric analysis. Statistical analysis showed that the surface of the stained neurons increased as a function of two parameters of time, the gestational age of the cells and the duration of the cultures. The complexity of the shape of the serotonin neurons characterized by the shape factor, the number of bifurcations and the morphological feature (bipolar or multipolar) was found to increase with the gestational age. It appears that the in vitro development of the embryonic cells which represents stages of maturation and differentiation can be specifically evaluated. Such an analysis of fetal central nervous system cells improves the knowledge of factors important in grafting experiments. We verified that the two drugs do not appreciably alter the in vitro development of the treated cells; thus they may be considered as promising drugs for human neuroprotection.  相似文献   

2.
Neuroendocrine response to stress stimuli is aimed to maintain body homeostasis. The activation of the neuroendocrine system is accomplished mainly by two ways: by feedback regulation based on the recognition of altered metabolic homeostasis by appropriate receptors sending the signal into the CNS, and by forward regulation involving a direct stimulation of the neuroendocrine system by a central command coming from an activated brain regulatory center. With regard to mechanisms of neuroendocrine activation, the signal specificity and site of its origin are of particular importance. The significance of the signal in neuroendocrine responses has been evaluated in three different stress conditions: hypoglycemia, surgical trauma and dynamic physical exercise. The stimulus inducing neuroendocrine response during hypoglycemia is the glucopenia. The signal for the activation of the neuroendocrine response is generated in glucosensitive cells which are not located in a single brain structure (hypothetical glucostat). The signal for growth hormone, vasopressin and oxytocin release is produced in brain structures protected by the blood-brain barrier, that for ACTH release in regions both protected and unprotected by the barrier, while the signal for prolactin release is generated in tissues lacking the blood-brain barrier. The neuroendocrine response during surgical trauma is activated by a signal formed in the damaged tissue reaching the CNS by neural pathways. Moreover, cytokins may participate on endocrine stimulation in those surgical interventions in which a large amount of bacterial endotoxins is released. During a complicated surgery, e.g. during a bypass other signals and modifying factors, such as hypothermia, dilution of blood, hypoperfusion of organs, rewarming of the body and hormone degradation in the oxygenator are important. On the On the other hand, during a short-term dynamic exercise, a forward regulation by a central signal from the activated CNS motor center comes into play with the consequent release of catecholamines, growth hormone, etc. In the control of some other hormones (beta-endorphin, partly ACTH) and especially during a long term exercise, neural signals from working muscles (feedback) are also involved. During a static exercise mainly catecholamines triggered by signals from working muscle cells are activated. The understanding of the signal and mechanisms of neuroendocrine activation during stress is indispensable for selective modulation of physiological and pathological responses.  相似文献   

3.
Thirty-nine thyroid nodules, removed because of recent growth, were analyzed morphologically by serial histological sections for the classical histomorphological hallmarks of follicular cell replication and for immunohistochemically demonstrable overexpression of the growth-associated ras-gene product p21ras. Clonal analysis was performed using the highly informative probe M27 beta that detects polymorphisms on the locus DXS255 of the X-chromosome. Twenty-four nodules were of clonal and 15 nodules were of poly-clonal origin. Only 3 out of the 24 clonal nodules were histomorphologically uniform. In all others, the structural hallmarks of active growth and the P21ras growth-marker expression were remarkably heterogeneous throughout the tumors. There were no histomorphological characteristics distinguishing these clonal tumors from polyclonal nodules. Even if a clonal thyroid tumor may be originally homogeneous in respect to the parameters studied here, mechanisms must exist that create wide heterogeneity of growth and of morphogenetic potential among the individual follicular cells during further expansion of the nodule. Thus, clonal nodules are much more common in nodular goiters than hitherto assumed on grounds of the classical morphological criteria. The diagnosis of a true monoclonal nodule can no longer rely on morphological and functional criteria alone but requires molecular or cytogenetic analysis of clonality.  相似文献   

4.
12 hearts with Ebstein's anomaly were studied. This disease is a combined anomaly of heart formation with dysplasia of the folds of the tricuspid valve (TV), its tendinous chordas and papillary muscles, dysplasia of the trabecular part of the right ventricle and dysplastic interrelationships between TV and the right ventricle: attachment by short chordas of posterior and septal folds of TV with the right ventricle walls, anomalous distal attachment of the anterior fold of TV. "Atrialisation" of the right ventricle is the reflection of the folds dysplasia the extreme form of which is the loss of communication between TV and trabecular part and formation of the direct communication between TV and the infundibular part of the right ventricle.  相似文献   

5.
Sequences of the alpha1, alpha2 and theta globin genes from six equid species have been determined to investigate relationships within the genus Equus. Analyses using standard phylogenetic methods, or an approach designed to account for the effects of gene conversion between the alpha genes, gave broadly similar results and show that the horses diverged from the zebra/ass ancestor approximately 2.4 million years ago and that the zebra and ass species arose in a rapid radiation approximately 0.9 million years ago. These results from the alpha genes are corroborated by theta gene data and are in contrast to mitochondrial DNA studies of the phylogeny of this genus, which suggest a more gradual set of speciation events.  相似文献   

6.
A light microscopic study of the spiral ganglion was done in human embryos and fetuses measuring 45, 50, 60, 74, 90, 134, 270 mm crown-rump length (crl), and in a one-day-old neonate. Morphometric evaluations of i) cell and nuclear area, ii) nuclear area/cell area ratio, iii) ganglion area, iv) cell concentration/surface unit, and v) distance between the first neuron and the receptor were made, and the results statistically evaluated. In earlier stages of development, spiral ganglion primordia appeared as a cluster of neuroblasts and some schwannoblasts immersed in the mesenchymal tissue, close to the ductus cochlearis. A honeycomb pattern in the spiral ganglion neurons was observed in the basal turn of a 74 mm crl fetus. In later stages, the basal turn of a 90 mm crl fetus showed a spatial organization. Peripheral and central fibers of the acoustic nerve appeared stratified in early periods of development (45 mm crl embryo). From this stage on, both phenomena progress apicalwards until the neonatal period. A significant decrease in the nuclear area/cell area ratio was observed from the 134 mm crl fetus (17 weeks) to the neonatal stage in all turns. This led to a significant increase in cellular area from the 270 mm crl fetus (32 weeks) to the neonate, with no significant variation in nuclear area. The distance from the primordium of the organ of Corti to the spiral ganglion in the interval between 45 and 74 mm crl showed a significant increase in all turns.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
Paclitaxel (Taxol) is a new class of anti-tumor agents which act by promoting the assembly and inhibiting the disassembly of microtubules. Single-agent studies have shown its significant activity for advanced cancers in various organs including ovary, lung, breast, and head and neck. Combination therapies with other anticancer agents have been extensively investigated in these cancers. Paclitaxel combined with cisplatin is now considered to be the standard treatment for advanced ovarian cancer. In other cancers, promising results have been obtained in several studies of paclitaxel-based chemotherapy. Major toxicities of paclitaxel-monotherapy are hypersensitivity reaction, neutropenia, and peripheral neuropathy. Combination of other cytotoxic agents sometimes leads to severer toxicities such as neurotoxicity with cisplatin and cardiotoxicity with anthracycline. Although further evaluation is needed, paclitaxel will be a main agent in the treatment of advanced solid tumors.  相似文献   

8.
BACKGROUND: Neovascularization reportedly is correlated with metastasis, recurrence, and prognosis in some types of tumors. Microvessel quantification in so-called "hot spots" has been studied extensively as the only factor reflecting angiogenesis in various malignant tumors. The objective of this report was to evaluate multiple morphometric microvascular characteristics in addition to microvessel density (MVD) in colorectal carcinomas to provide a better approach to examining the relation between angiogenesis and clinicopathologic factors and prognosis. METHODS: Histologic sections from 106 colorectal adenocarcinomas and 17 adenomas, immunostained for factor VIII, were evaluated by image analysis for the quantification of MVD, total vascular area (TVA), and microvascular branching, as well as several morphometric parameters related to the vessel size or shape. RESULTS: MVD gradually decreased with progressing Dukes stage. The vascular branching counts were significantly higher in carcinomas than in adenomas, and remained unaffected through progressing Dukes stages. Shape-related parameters showed significant differences between carcinomas and adenomas and between different grades of differentiation. Branching counts and TVA were the only factors found to be of prognostic significance. CONCLUSIONS: This study provides evidence that neovascularization is an early critical event in colorectal tumorigenesis, reaching a maximum level early in the malignant process. Its prognostic significance is better assessed by quantification of TVA and the branching pattern of microvessels, whereas MVD does not provide significant prognostic information for colorectal carcinoma patients.  相似文献   

9.
In an epidemiological study, markers of bone formation (serum osteocalcin and C-terminal propeptide of type I collagen) and bone resorption [urinary type I collagen peptides (Crosslaps), urinary total pyridinoline (TPYRI), urinary deoxypyridinoline (DPYRI) as well as female sex hormones (serum estradiol)], follicle-stimulating hormone (FSH) and luteinizing hormone were measured in 237 women. This cohort aged 44-66 years, came for their first medical examination since menopause to the outpatient menopause clinic at the Kaiser-Franz-Josef-Hospital, Vienna. The women were all 0.5-5.0 years since cessation of menses and were not taking medications other than hormone replacement therapy [52 cases, 21.9%)] and had no diseases known to affect bone and mineral metabolism. The best correlation was found between urinary DPYRI and urinary TPYRI (r = 0. 63, P = 0.0001), followed by urinary Crosslaps and urinary DPYRI (r = 0.47, p = 0.0001). Only weak but significant correlations between E2 and urinary Crosslaps (r = -0.21, P < 0.0001) as well as serum E2 and serum osteocalcin (r = -0.16, P = 0.0007), were observed. Of the 237 women 53% suffered from a severe E2 deficiency (E2 < 10.0 ng/liter). In these patients, urinary Crosslaps (+48%) and serum osteocalcin (+22%) were significantly higher (P < 0.0001) compared with those patients with E2 levels > 10 ng/liter. Women with E2 levels >10 ng/liter were further subdivided into those with and without sex hormone replacement therapy, whereby no statistical differences in any of the biochemical markers could be observed between these groups. We could clearly demonstrate that in postmenopausal women suffering from severe E2 deficiency (E2 < 10 ng/liter), urinary Crosslaps and serum osteocalcin are significantly increased, indicating in principle a clear correlation between E2 deficiency and these markers of bone turnover.  相似文献   

10.
The interaction between three independent data sets (anatomy/morphology, cytology, molecules) has been evaluated within the controversial genus Trichomanes (Hymenophyllaceae). Anatomy/morphology, cytology, and rbcL sequences, despite their high and significant level of incongruence, were thus empirically combined with differential weighting in a cladistic analysis within Trichomanes in order to give an appreciation of the contribution of each data set in the resulting topologies and to study more precisely the nature of potential conflicts. Results show that any standard statistics values (such as bootstrap) do not appear to be objectively useful for the choice of the "best" topology or the "good" clades provided by the combination. This weighting approach reveals three cases: (i) some clades (such as subgenus Didymoglossum) are always retrieved and correspond to the absence of conflicts between the different data, (ii) some new clades (such as subgenus Achomanes) are either provided or reenforced as a "synergetic" result of the combination of the data and (iii) that remaining conflicting clades reflect the persistence of incongruence between data whatever the weighting.  相似文献   

11.
During the course of aging both activation and degenerative changes are found in the human hypothalamus. Degeneration may start around middle-age in some neurotransmitter- or neuromodulator-containing neurons. For instance, a decreased number of vasoactive intestinal polypeptide (VIP) neurons was observed in the suprachiasmatic nucleus (SCN) of middle-aged males. The normal circadian fluctuations seen in the number of vasopressin (AVP) neurons in the SCN of young subjects diminished in subjects older than 50 years. Moreover, a sharp decline in cell number was found in the sexually dimorphic nucleus (SDN) after 50 years in males. On the other hand, many hypothalamic systems remain perfectly intact during aging like the oxytocin (OXT) neurons in the paraventricular nucleus (PVN). The AVP neurons in the PVN are activated during aging as appears from their increasing cell number. Also the corticotrophin-releasing hormone (CRH) neurons of the PVN are activated in the course of aging, as indicated by their increased number and their increased AVP coexpression. Part of the infundibular nucleus, the subventricular nucleus, contains hypertrophic neurokinin B neurons in postmenopausal women. It can be concluded that a multitude of changes in the various hypothalamic nuclei may be the biological basis for many functional changes in aging, i.e., both endocrine and central alterations, and that only a minority of the possible human hypothalamic changes have so far been studied.  相似文献   

12.
PURPOSE OF THE STUDY: The goal of this study was to specify criteria of femoro-patellar joint normality on lateral view. MATERIAL: This study was based on radiological examination of 102 knees in 51 adults (average age 26.1 years). It concerned 29 women and 22 men that had never suffered from their knee and were supposed healthy. METHODS: The radiological protocol was the following: a lateral view at 45 degrees of flexion, two lateral views in extension, with and without quadriceps contraction. The analysis was focused on patellar surface aspect, its height, its depth and covering measurement. RESULTS: We found 83.7 per cent of so-called "normal" patellar surface, and 12.7 per cent of "abnormal" patellar surface (dysplasia) in the absence of pain. DISCUSSION: We have confirmed figures advanced in others series of the literature concerning patellar height and patellar surface, as well as patellar surface depth and covering. We have underlined the interest of lateral views; in extension with quadriceps contracted and relaxed. Finally, we have defined a trochleo-patellar sign that allows to correlate patellar height to patellar surface height (ITP = 0.35 to 0.84). CONCLUSION: This study insists on the interest of radiological lateral views of the knee and determine criteria for normalities.  相似文献   

13.
This article presents a proposal for the establishment of a new adenovirus genus to accommodate certain bovine, ovine, and avian adenoviruses with special characteristics which differentiate them from members of the existing genera Mastadenovirus and Aviadenovirus. This proposal has been developed from earlier versions with advice from the Adenovirus Study Group of the International Committee on Taxonomy of Viruses (ICTV).  相似文献   

14.
Recent studies have shown that experimental tumors could be treated more efficiently with ionizing radiation if genetic material was transfered into tumor cells. Several approaches have been reported, and among them, the first one consisted of increasing the apoptotic response to radiation by modulating genes involved in the regulation of the apoptotic pathway. Indeed the modulation of p53 and bcl-2 gene expression has recently been used successfully in several experimental models to increase the apoptotic death after radiation. A second approach consisted of taking advantage of the conditional expression of some genes after exposure to ionizing radiation. Indeed, some genes exhibit a radio-inducible promoter which can be combined to a gene, able to enhance or decrease the biological effect of radiation. The irradiation of such a transgene under the control of a radio-inducible promoter can lead to a second biological effect, concomitant to the irradiation, as reported for the TNF alpha under the control of the EGR (early growth response) promoter. A third approach consisted of enhancing the effect of radiation induced tumor cell death by the expression of a suicide gene in these cells, as suggested recently for the HSV-tk (herpes virus thymidine kinase gene). These preliminary results obtained in experimental models appear to be very promising and might improve the efficacy and specificity of radiation therapy in a not too distant future.  相似文献   

15.
Combination of morphological and electrophysiological techniques provided data, suggesting existence in the young rat striatum of a peculiar class of neurons, the neurogliaform or dwarf neurons. Striatal neurons (n = 92), intracellularly recorded from rat brain slices, were filled (one in each slice) with the intracellular marker biocytin, to compare physiological and morphological properties in the same cell. Moreover, some neurons (n = 7) were filled with biocytin plus the fluorescent calcium indicator fura-2, identifying cells during electrophysiological recording. Electrophysiological recording showed that striatal neurons had different firing patterns, suggestive in most cases (n = 80) of spiny neuron class and in others (n = 12) of interneuron class. Fura-2 injection clearly identified the body of six medium-sized cells and of one distinctive tiny cell. This small cell, however, showed a resting membrane potential and spontaneous and evoked firing pattern characteristic of striatal interneurons. Moreover, the fura-2 injected in such small neuron also completely filled the cell body of a near large neuron; the fura-2 fluorescence changed synchronously in the two paired neurons after electrical stimulation of the impaled small one. Accordingly, the biocytin staining identified the morphology of the small recorded neuron as a neurogliaform-like cell apposed to a dendrite of an aspiny neuron, suggesting that the dye injected in one neuron had diffused to the other of a different type. Furthermore, such heterologous dye coupling unexpectedly involved seven pairs of cells detected with biocytin staining (7.6% of the recorded neurons), invariably represented by a medium or large neuron on one side, and on the other side by a small (5.44 +/- 0.15 x 9.14 +/- 0.7 microns, mean +/- SD; n = 7) neurogliaform cell, roundish in shape with few slender and short processes, usually apposed to a dendrite of the companion neurons (six out of seven). In the other cases, the biocytin staining revealed in each slice either the morphology of single spiny or aspiny neurons (80.4% of recorded neurons), or of two-three medium-sized spiny neurons detected near to each other, suggesting that dye coupling had occurred typically between similar neurons (11.9% of the recorded neurons). These data suggest that some neurogliaform cells in the striatum of young rat can be identified as dwarf interneurons, that may be dye-coupled with neurons of different classes.  相似文献   

16.
Symmetry of posterior intrasylvian cortices (e.g., planum temporale, planum parietale) has been suggested to represent a risk factor for developmental disorders of language and reading. Using high-resolution magnetic resonance morphometry, we studied 21 right-handed children with developmental language disorder of the phonologic-syntactic type, and found normal left-right asymmetry of the planum temporale and planum parietale when compared with 21 matched controls. The planum temporale was bilaterally smaller in the affected children, a finding accounted for by their approximately 7% smaller forebrain size. Our data do not support a role of gross visible unilateral or bilateral abnormalities of posterior intrasylvian ontogenesis in this disorder.  相似文献   

17.
Goats which have recovered from acute Anaplasma ovis infection remain seropositive, although infected erythrocytes cannot be detected by microscopic examination. Persistence of A. ovis 17 to 21 months following experimental infection was demonstrated by PCR detection of the msp-5 gene. Quantitative analysis of persistent rickettsemia over time showed that all levels were below the limit of microscopic detection and ranged from a low of 10(2) organisms/ml to peaks of 10(6) organisms/ml. Two patterns of persistent rickettsemia were observed: the first was characterized by cyclic fluctuations at 6- to 9-week intervals, similar to the pattern described for A. marginale-infected cattle, while in the second pattern, repetitive cycles did not occur and the rickettsemia levels were relatively constant. The msp-2 and msp-3 multigene families, which provide the genetic capacity for outer membrane protein antigenic variation during persistent A. marginale rickettsemia, were identified in the A. ovis genome by Southern blot analysis, and expression of an MSP-2 homologue was confirmed by using immunoblots.  相似文献   

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20.
This study provides quantitative information on the effect of sodium fluoride (NaF) on the testes of F1 generation male rats exposed in utero and during lactation to NaF at one of four concentrations (25, 100, 175, 250 ppm). At weaning, the F1 generation males were exposed to NaF in their drinking water for 14 weeks, after which time testicular tissues were perfusion-fixed with glutaraldehyde and observed after being embedded in plastic. The seminiferous tubules comprised 89%, 87%, 88%, 88% and 88% of the total testis volume while the interstitial space occupied 9.3%, 11.2%, 10.2%, 9.8% and 9.9% of the total testis volume for the 0, 25, 100, 175 and 250 ppm NaF treatment groups, respectively. Statistically significant differences between control and NaF-treated rats were not observed with respect to absolute volume of the seminiferous tubules, interstitial space, Leydig cells, blood vessels boundary layer, lymphatic space, macrophages, tubular lumen or absolute tubular length and absolute tubular surface area, mean Sertoli cell nucleoli number per tubular cross-section, mean seminiferous tubule diameter and the mean height of the seminiferous epithelium. A statistically significant decrease in the absolute volume and volume percent of the lymphatic endothelium was observed in the 175 and 250 ppm NaF-treated groups and in the testicular capsule in the 100 ppm NaF-treated groups. The significance of this finding is unknown at the present time. Overall, the quantitative information obtained suggests that exposure to NaF at the doses used in the present study does not adversely affect testis structure or spermatogenesis in the rat.  相似文献   

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