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1.
The protein/glycoprotein composition of Triton X100 extracts of four metastatic tumour lines have been compared by gel electrophoresis after the implantation into different sites of the body. No consistent differences in the patterns were noted after staining with Coomassie Blue or treating with concanavalin A. In contrast, after treating with wheat germ agglutinin (WGA), the patterns varied with site. This was most marked with the ML and M5 tumours, where the overall binding was much lower for some sites. Although WGA binding with the LL and BL6 tumours was generally higher than with the ML and M5, reduced binding was still evident for some sites. Reduced WGA binding was also observed for extracts of secondary tumour growing in the liver or lungs.  相似文献   

2.
Cytological preparations for the fluorescent in situ hybridization (FISH) technique require cytoplasm-free metaphases, with well-spread chromosomes, for the localization of DNA sequences and chromosome mapping. We tested various procedures for FISH analysis of Passiflora cacaoensis, P. gardneri and hybrid F? progeny of P. gardneri x P. gibertii. Two treatments with four enzymes and three incubation times were compared. The material was treated with 1.0 M HCl before enzymatic digestion. The following criteria were used to determine the quality of the metaphases: a) lack or presence of cytoplasm; b) well-spread chromosomes or with overlap; c) complete or incomplete chromosome number (2n). The enzyme Pectinex(?) SP ULTRA gave the best performance, with the shortest incubation time. The best results were observed after 30 min of incubation; more than 70% of the metaphases did not have large amounts of cytoplasm or overlapping chromosomes, and about 75% maintained the chromosome number. FISH was carried out using a 45S rDNA probe (pTa71) labeled with biotin and detected with fluorescein isothiocyanate. Sites with strong staining and without nonspecific signals were observed. Our methodological adaptations allowed the preparation of metaphase slides of high quality for the FISH technique, with less time required for the preparation of samples.  相似文献   

3.
The majority of patients with chronic myeloid leukemia in early chronic phase (CML-ECP) who are treated with imatinib achieve a complete cytogenetic response with a significant reduction in the risk of progression to advanced phases. Recent studies show that therapy of CML-ECP with nilotinib leads to a faster and deeper response compared to imatinib. However, in vitro data indicates that there is no detectable difference in inhibition of signaling downstream of Bcr-Abl between the two agents, and that neither drug induces apoptosis of CML CD34+ cells. We use a computational model of hematopoiesis and CML combined with serial quantitative data of disease burden under imatinib and nilotinib therapy to explain this apparent disconnect between in vivo and in vitro responses. We show how a subtle difference in the differentiation rate of CML cells under therapy with either agent, with marginal impact onto the in vitro studies, translates into a significantly different reproductive fitness of treated cells in vivo, providing a sizeable difference, hence providing an explanation for the superior response observed with nilotinib.  相似文献   

4.
Sister chromatid exchange (SCE), percentage of first, second, third mitoses, blastic transformation index and mitotic index in patients with myelodysplastic syndrome (MDS) (3 with refractory anaemia, 2 with refractory anaemia with sideroblasts, 1 with refractory anaemia with excess of blasts, 4 with refractory anaemia with excess of blasts in transformation) and in 15 healthy volunteers were estimated. Three types of lymphocytes cultures were set up: first with phytohemaglutinin (PHA), second with PHA and bromodeoxyuridine (BRdU), third with BRdU. In healthy persons the SCE frequency was negatively correlated to proliferating rate index, but in MDS such correlation was not found. The lymphocytes cell cycle duration based on percentage of mitoses was longer in MDS patients than in controls. The results of our studies show the disturbances of lymphocytes during cell cycle division resulting in higher SCE frequency and lower proliferating rate compared to controls.  相似文献   

5.
In a preliminary study rubidomycin was found capable of inducing remission in adults with acute leukaemia, the remission rate in acute myeloblastic leukaemia comparing favourably with that achieved with previous forms of therapy. Marrow aplasia and cardio-toxicity occurred in a number of patients. Supportive measures during the former and early recognition by frequent electrocardiography can do much to mitigate these toxic effects.  相似文献   

6.
The primary goal was to compare results from a free-operant procedure with pigeons [Machado, A., Guilhardi, P., 2000. Shifts in the psychometric function and their implications for models of timing. J. Exp. Anal. Behav. 74, 25-54, Experiment 2] with new results obtained with rats. The secondary goal was to compare the results of both experiments with dependent variables that were not used in the original publication. As in the original study with pigeons, rats were trained on a two-alternative free-operant psychophysical procedure in which left lever press responses were reinforced during the first and second quarters of a 60-s trial, and right lever press responses were reinforced during the third and fourth quarters of the trial. The quarters were reinforced according to four independent variable interval (VI) schedules of reinforcement. The VI duration was manipulated in each quarter, and shifts in the psychophysical functions that relate response rate with time since trial onset were measured. The results obtained with rats were consistent with those previously obtained with pigeons. In addition, results not originally reported were also consistent between rats and pigeons, and provided insights into the perception, memory, and decision processes in Scalar Expectancy Theory and Learning-to-Time Theory.  相似文献   

7.
We report the identification of two orthobunyaviruses, Melao virus (MELV) and Oropouche virus (OROV), in plasma specimens from Haitian children with acute febrile illness who presented during outbreaks caused by alpha- and flaviviruses in 2014. Heretofore not described as a human pathogen, MELV was isolated in cell culture from the plasma of five case patients. OROV RNA was detected in the plasma of an additional child, using an unbiased sequencing approach, with phylogenetic inference suggesting a close relationship with strains from Brazil. Abdominal pain was reported by four case patients with MELV infections, with lymphadenopathy noted in two cases. Our findings document the occurrence of these orthobunyaviruses within the Caribbean region and highlight the critical importance of surveillance with viral genome sequence analyses to identify outbreaks caused by these and other emerging viruses.  相似文献   

8.
Using polarographic oxygen microelectrodes, distribution of oxygen tension (pO2) in the rat cerebral arterioles (with a lumen diameter of 8-80 microm) and venules (with a lumen diameter of 8-120 microm) has been studied in acute reduction of haemoglobin concentration in the blood. Isovolumic haemodilution with 5 % albumin solution has been performed stepwise from 14 g/dl (control) to 10 g/dl (step 1), 7 g/dl (step 2) and to 4.6 g/dl (step 3). It was shown that step 1 of haemodilution led to no impairment of oxygen supply to the brain cortex. Step 2 resulted in moderate increase of pO2 in arterioles, whereas in venules oxygen tension fell down substantially (on the average, to 32 mm Hg). Step 3 resulted insignificant increase of pO2 in arterioles. A further fall of pO2 (to 27 mm Hg) in studied venules was recorded. The portion of venules with low pO2 grew to 31% (only 3 % in control). Microregions with a near-to-zero pO2 were recorded in some capillaries. This indicates presence of hypoxic zones in brain tissue. Hypoxic and anoxic microregions originate at this stage of anemia in locations with relatively low and/or impaired blood supply.  相似文献   

9.
Fibronectin is a glycoprotein found in soluble form in plasma and in an insoluble form in connective tissue matrices. Fibronectin isolated from canine peritoneal effusions by affinity chromatography on gelatin-Sepharose was found to be immunologically indistinguishable from the plasma form, as shown by double immunodiffusion techniques. Utilizing an enzyme immunoassay technique, 7 patients with disseminated splenic hemangiosarcoma were found to have peritoneal fibronectin concentrations of 309 ± 133 (mean ± SD) μg/ml. In 8 patients with widespread lymphoma the peritoneal fibronectin concentrations were 323 ± 147 μg/ml. In 5 patients with hepatoma the peritoneal fibronectin concentrations were 361 ± 121 μg/ml. In 6 patients, 2 with mesothelioma, 2 with pancreatic adenocarcinomas, and 2 with prostatic adenocarcinoma, the peritoneal fibronectin concentrations were 315 ± 115 μg/ml. The lowest concentrations 117 ± 46 μg/ml, were found in patients with malignant disease and concurrent peritoneal thrombus formation. These data suggest that decreased fibronectin concentrations in peritoneal effusions are associated with, at least, a locally hypercoagulable state.  相似文献   

10.
This work was carried out to characterize starch accumulation and activities of key enzymes during grain filling in two wheat cultivars differing in starch content. The results showed that the starch accumulation rate (SAR) and activities of sucrose synthase, ADP-glucose pyrophosphorylase, soluble starch synthase, granule-bound starch synthase, and starch branching enzyme in the cultivar with a high starch content were significantly higher than those in the cultivar with a low starch content. The simulation with Richards’ equation showed that it was average starch accumulation rate but not active starch accumulation duration that determined starch accumulation. As compared with the cultivar with a low starch content, plants of the cultivar with a high starch content maintained the higher SAR and greater activities of related enzymes during mid and late grain filling stages. Consequently, the cultivar with a high starch content had advantages over that with a low starch content in terms of the amount of starch accumulation at mid and late grain filling stages.  相似文献   

11.
Significant hyperkalaemia occurred in 406 out of 29 063 patients admitted to a major Scottish teaching hospital in one year (1.4%). Mortality was higher in these patients than in control patients and was strongly correlated with the severity of the hyperkalaemia. Overall seven deaths were directly due to hyperkalaemia (out of 58 deaths among patients with hyperkalaemia). Factors contributing to a poor prognosis were severity and speed of onset of hyperkalaemia and the presence of appreciable renal impairment. Patients with hyperkalaemia were older and more likely to be male; this trend was present in all diagnostic subcategories. Genitourinary disease, gastrointestinal disease, and cancer were significantly more common among the patients with hyperkalaemia than the controls. Hyperkalaemia due to drug treatment was invariably mild and non-fatal, whereas genitourinary disease was often associated with moderate to severe hyperkalaemia, which in two cases proved fatal. Use of electrocardiographic monitoring was rare, and although the treatment of hyperkalaemia was effective, it was often used when not required. Hyperkalaemia is a potential hazard in diabetic ketoacidosis, and use of potassium supplements should be carefully monitored during correction of the acidosis.  相似文献   

12.
Changes in Brain Protease Activity in Aging   总被引:2,自引:1,他引:1  
Abstract: We measured changes in protease activity with aging, conducting assays of cathepsin D and calpain II activities and the rate of degradation of cytoskeletal proteins, preparing the enzymes and substrates from young and aged brains. Calpain preparations added to the young and to the aged substrates were standardized with casein as substrate so that age-related changes in calpain specificity and substrate susceptibility were measured. Several age-related differences were observed in substrate susceptibility and in enzyme activity. With respect to substrate, the neurofilament protein from young animals was somewhat more susceptible to calpain action than that from older animals. With respect to enzyme activity, calpain from aged brain cleaved neurofilament protein at a faster rate than did calpain from young. With neurofilaments, the most rapid breakdown usually occurred when enzyme from aged tissue was incubated with substrate from young. Kidney enzyme of aged rats incubated with neurofilament substrate of aged rats resulted in a more rapid breakdown than enzyme of young kidney incubated with substrate of young. The age dependence of tubulin breakdown was somewhat different from that of neurofilament breakdown. The most rapid breakdown usually occurred when using enzyme from young with tubulin from young. Incubation of neurofilament protein or tubulin with cathepsin D did not reveal any differences with aging. These studies suggest that an increase in enzyme activity observed previously during aging may also include changes in the properties of the enzyme (substrate specificity) and/or in the properties of their endogenous substrates (susceptibility to breakdown).  相似文献   

13.
Problems of maintaining therapy for acute myelocytic leukemias in adults are discussed. The analysis of the maintaining therapy in 22 patients affected with an acute myelocytic leukemia and living for more than 6 months revealed that the interval therapy with a high dosage of cytostatic combinations in the sense of the COAP scheme is preferable compared with the daily administration of 6-mercaptopurin, in addition methotrexate twice a week. Reasons for this are discussed.  相似文献   

14.
Defects in mitochondrial energy metabolism have been implicated in the pathology of several neurodegenerative disorders. In addition, the reactive metabolites generated from the metabolism and oxidation of the neurotransmitter dopamine (DA) are thought to contribute to the damage to neurons of the basal ganglia. We have previously demonstrated that infusions of the metabolic inhibitor malonate into the striata of mice or rats produce degeneration of DA nerve terminals. In the present studies, we demonstrate that an intrastriatal infusion of malonate induces a substantial increase in DA efflux in awake, behaving mice as measured by in vivo microdialysis. Furthermore, pretreatment of mice with tetrabenazine (TBZ) or the TBZ analogue Ro 4-1284 (Ro-4), compounds that reversibly inhibit the vesicular storage of DA, attenuates the malonate-induced DA efflux as well as the damage to DA nerve terminals. Consistent with these findings, the damage to both DA and GABA neurons in mesencephalic cultures by malonate exposure was attenuated by pretreatment with TBZ or Ro-4. Treatment with these compounds did not affect the formation of free radicals or the inhibition of oxidative phosphorylation resulting from malonate exposure alone. Our data suggest that DA plays an important role in the neurotoxicity produced by malonate. These findings provide direct evidence that inhibition of succinate dehydrogenase causes an increase in extracellular DA levels and indicate that bioenergetic defects may contribute to the pathogenesis of chronic neurodegenerative diseases through a mechanism involving DA.  相似文献   

15.
Unselected population-based nationwide studies on the excess mortality of individuals with severe mental disorders are scarce with regard to several important causes of death. Using comprehensive register data, we set out to examine excess mortality and its trends among patients with severe mental disorders compared to the total population. Patients aged 25–74 and hospitalised with severe mental disorders in 1990–2010 in Finland were identified using the national hospital discharge register and linked individually to population register data on mortality and demographics. We studied mortality in the period 1996–2010 among patients with psychotic disorders, psychoactive substance use disorders, and mood disorders by several causes of death. In addition to all-cause mortality, we examined mortality amenable to health care interventions, ischaemic heart disease mortality, disease mortality, and alcohol-related mortality. Patients with severe mental disorders had a clearly higher mortality rate than the total population throughout the study period regardless of cause of death, with the exception of alcohol-related mortality among male patients with psychotic disorders without comorbidity with substance use disorders. The all-cause mortality rate ratio of patients with psychotic disorders compared to the total population was 3.48 (95% confidence interval 2.98–4.06) among men and 3.75 (95% CI 3.08–4.55) among women in the period 2008–10. The corresponding rate ratio of patients with psychoactive substance use disorders was 5.33 (95% CI 4.87–5.82) among men and 7.54 (95% CI 6.30–9.03) among women. Overall, the mortality of the total population and patients with severe mental disorders decreased between 1996 and 2010. However, the mortality rate ratio of patients with psychotic disorders and patients with psychoactive substance use disorders compared to the total population increased in general during the study period. Exceptions were alcohol-related mortality among patients with psychoactive substance use disorders and female patients with psychotic disorders, as well as amenable mortality among male patients with psychotic disorders. The mortality rate ratio of persons with mood disorders compared to the total population decreased. The markedly high mortality amenable to health care intervention among patients with severe mental disorders found in our study suggests indirectly that they may receive poorer quality somatic care. The results highlight the challenges in co-ordinating mental and somatic health services.  相似文献   

16.
IgA-antibodies to pneumococcal antigens were measured by enzyme immunoassay in saliva and nasal washings, obtained from 32 children aged 6 months to 14 years with acute pneumonia and from 25 healthy children aged 2.5-11 years. In the secretions of children with acute pneumonia an essential increase in the levels of IgA-antibodies in comparison with those observed in healthy children was detected. The levels of antibodies to pneumococci in saliva and in nasal washings were in direct correlation. These data are indicative of a protective role played, probably, by secretory antibodies at the portals of infection in pneumococcal pneumonia.  相似文献   

17.
Chemoattractant-elicited increases in myosin phosphorylation in Dictyostelium   总被引:31,自引:0,他引:31  
Cyclic AMP stimulation of chemotactically competent Dictyostelium amebas labeled with [32P]orthophosphate transiently increases phosphorylation in the heavy chain and the 18,000 dalton light chain of myosin. Immediately before the increase, heavy chain phosphorylation transiently decreases. These phosphorylation changes also occur when cAMP-induced activation of adenylate cyclase is blocked by pretreatment of amebas with caffeine. The time course of these phosphorylation responses correlates with the shape changes induced in amebas exposed to a temporal increase in cAMP concentration. The dose dependence of the phosphorylation responses is the same as that previously determined for chemotaxis. The phosphorylation responses exhibit adaptation properties in common with those of the shape change response and chemotaxis. Increases in the rate of myosin heavy chain and light chain phosphorylation can be observed in vitro by stimulating unlabeled amebas with cAMP and then lysing the cells into a gamma-[32P]ATP-containing reaction mixture.  相似文献   

18.
One hundred and three children with proved typhoid fever were treated with trimethoprim-sulphamethoxazole, and the results compared with those of a further 40 children treated with chloramphenicol. The bacteriological response to trimethoprim-sulphamethoxazole was unsatisfactory. From this study it seems that at present chloramphenicol is still the treatment of choice for typhoid fever. In view of the haematological changes occurring during therapy with trimethoprim-sulphamethoxazole caution is necessary and monitoring of the blood picture advisable, even at the recommended dose.  相似文献   

19.
The testes are active during gestation, as well as during early infancy. Testosterone elevation during fetal development has been shown to play a role in human neurobehavioral sexual differentiation. The role of early postnatal gonadal activation in human psychosexual development is largely unknown, however. We measured testosterone in 48 full term infants (22 boys, 26 girls) by monthly urinary sampling from day 7 postnatal to age 6 months, and related the area under the curve (AUC) for testosterone during the first 6 months postnatal to subsequent sex-typed behavior, at the age of 14 months, using the Pre-School Activities Inventory (PSAI), and playroom observation of toy choices. In boys, testosterone AUC correlated significantly with PSAI scores (Spearman's rho = 0.54, p = 0.04). In addition, play with a train and with a baby doll showed the anticipated sex differences, and play with the train correlated significantly and positively with testosterone AUC in girls (Spearman's rho = 0.43, p = 0.05), while play with the doll correlated significantly and negatively with testosterone AUC in boys (Spearman's rho = -0.48, p < 0.03). These results may support a role for testosterone during early infancy in human neurobehavioral sexual differentiation.  相似文献   

20.
不同固定条件下细胞与活细胞的原子力显微镜实时观察   总被引:3,自引:0,他引:3  
用原子力显微镜(atom force microscope,AFM)观察固定细胞的最佳条件并在生理溶液中对活细胞实时观察.用不同固定剂和同一固定剂的不同浓度处理细胞;不加任何固定剂而直接在生理溶液中对细胞进行AFM成像.以戊二醛为固定剂并使用0.5%~1%的浓度固定细胞,后用缓冲溶液漂洗,再对细胞进行成像时可获得质量良好的图像.直接在生理溶液中进行观察,成像质量低于使用固定剂的细胞,但保持了细胞的生活原貌.在用原子力显微镜高分辨率观察生理条件下细胞的特点时,需要在制样与观测系统两方面进行改进.  相似文献   

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