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1.
The unique anaemic syndrome of the Belgrade laboratory (b/b) rat is due to an intracellular iron deficiency which is induced by a not yet defined mutation, resulting in impairment of haemopoiesis. We investigated the CFU-Sd8 number and concentration in the peripheral blood of b/b rats to study the relationship between medullary and extramedullary haemopoiesis in this anaemic syndrome. The results show normal concentration of CFU-Sd8 in the peripheral blood of b/b rats. This finding was unexpected in the state of severe anaemia and disturbed growth factor production in b/b rats, where the mobilization of CFU-Sd8 from bone marrow to blood is expected. The results suggest that severe anaemia is not regularly accompanied by the mobilization of pluripotent progenitors from bone marrow to the blood.  相似文献   

2.
By means of radioautographic method, with 3H-thymidin application there were studied: mitotic activity, the number of DNA-synthesizing cells, growth fraction and population number of fibroblast culture irradiated with a single impulse of neodymium laser at energy density within 1 Dg/cm2--100 Dg/cm2. Under the influence of small doses of laser radiation (1--10 Dg/cm2) the number of dividing DNA-synthesizing cells increased, together with proliferative pool and the number of cells in the field of vision. At energy density of laser radiation equal to 50 Dg/cm2, and especially to 100 Dg/cm2 despite increased mitotic index and labelled cells index, registered during first hours of the effect, proliferative pool decreased and population growth rate lowered. These doses of laser radiation produced destruction of a rather large part of the cells in a monolayer.  相似文献   

3.
The effect of low doses mitomycin C (MMC) on DNA synthesis of fibroblast cell lines derived from normal individuals or patients with Fanconi anaemia (FA) was studied. Using low doses of MMC (12 ng/ml), little or no effect was observed on DNA synthesis of normal cells, whereas DNA synthesis of FA cells was greatly inhibited 24 and 48 h after treatment. This effect was due to a decrease in the number of DNA-synthesizing cells, while the amount of radioactivity incorporated per cell (as measured with grain counting in autoradiograms) remained the same. These findings indicate that the inhibition of semiconservative DNA synthesis induced by MMC in FA cells is not due to an inhibitory effect of unrepaired lesions on the rate of DNA synthesis but rather to a block in cell cycle progression.  相似文献   

4.
THe effect of low doses mitomycin C (MMC) on DNA synthesis of fibroblast cell lines derived from normal individuals or patient with Fanconi anaemia (FA) was studied. Using low doses of MMC (12 ng/ml), little or no effect was observed on DNA synthesis of normal cells, whereas DNA synthesis of FA cells was greatly inhibited 24 and 48 h after treatment. This was due to a decrease in the number of DNA-synthesizing cells, while the amount of radioactivity incorporated per cell (as measured with grain counting in autoradiograms) remained the same. These findings indicate that the inhibition of semiconservative DNA synthesis induced by MMC in FA cells is not due to an inhibitory effect of unrepaired lesions on the rate of DNA synthesis but rather to a block in cell cycle progression.  相似文献   

5.
We describe a method for microscopic identification of DNA-synthesizing cells in bacterioplankton samples. After incubation with the halogenated thymidine analogue bromodeoxyuridine (BrdU), environmental bacteria were identified by fluorescence in situ hybridization (FISH) with horseradish peroxidase (HRP)-linked oligonucleotide probes. Tyramide signal amplification was used to preserve the FISH staining during the subsequent immunocytochemical detection of BrdU incorporation. DNA-synthesizing cells were visualized by means of an HRP-labeled antibody Fab fragment and a second tyramide signal amplification step. We applied our protocol to samples of prefiltered (pore size, 1.2 μm) North Sea surface water collected during early autumn. After 4 h of incubation, BrdU incorporation was detected in 3% of all bacterial cells. Within 20 h the detectable DNA-synthesizing fraction increased to >14%. During this period, the cell numbers of members of the Roseobacter lineage remained constant, but the fraction of BrdU-incorporating Roseobacter sp. cells doubled, from 24 to 42%. In Alteromonas sp. high BrdU labeling rates after 4 to 8 h were followed by a 10-fold increase in abundance. Rapid BrdU incorporation was also observed in members of the SAR86 lineage. After 4 h of incubation, cells affiliated with this clade constituted 8% of the total bacteria but almost 50% of the visibly DNA-synthesizing bacterial fraction. Thus, this clade might be an important contributor to total bacterioplankton activity in coastal North Sea water during periods of low phytoplankton primary production. The small size and low ribosome content of SAR86 cells are probably not indications of inactivity or dormancy.  相似文献   

6.
Summary The ex vivo labelling of DNA-synthesizing epithelial cells in colonic and vaginal mucosa was compared with in vivo labelling. For this purpose, in vivo S-phase cells were labelled with [3H]thymidine (Tdr) and ex vivo labelling was continued by culturing tissue specimens in bromodeoxyuridine (BrdU). Various methods of tissue culture were employed in order to improve diffusion of medium (and BrdU) in the tissue. BrdU and 3H-TdR labelling were evaluated by immunohistochemistry and autoradiography respectively. Ex vivo labelling resulted in a patchy distribution of labelled cells, which did not correspond with the 3H-TdR labelling pattern obtained in vivo. Under the described conditions ex vivo labelling does not appear to be a reliable for estimation of the proliferative activities in vivo.  相似文献   

7.
Cyclic haemopoiesis in Grey Collie dogs is characterized by stable oscillations in all haemopoietic lineages. It is proposed that in these animals, in contrast to normal animals, the maturation process of haemopoietic (in particular granuloid) cells from the primitive progenitors to the functional cells is characterized by an abnormally strong synchrony. It is conjectured that the marrow maturation time has a very small variance compared with non-cyclic normal dogs. With a mathematical model of haemopoiesis it is shown that small fluctuations are amplified via regular feedback processes such that stable granuloid oscillations are established. Erythroid oscillations are induced indirectly by granuloid feedback to the stem cell pool. The model calculations further show that the synchrony hypothesis of bone marrow maturation can quantitatively explain the following experimental results: (1) the maintenance of stable cycles of granuloid and erythroid bone marrow and blood cells with a period of approximately 14 d; (2) the disappearance of granuloid and erythroid cycles during the administration of the colony stimulating factor rhG-CSF; (3) the reappearance of oscillations when the administration of CSF is discontinued; (4) the cessation of cycles during endotoxin application; and (5) the persistence of cycles during erythroid manipulations (bleeding anaemia, hypoxia, hypertransfusion). We therefore conclude that cyclic haemopoiesis is not caused by a defect in the regulatory control system but by an unusual maturation process.  相似文献   

8.
Prolactin immunostaining in combination with thymidine autoradiography was used to characterize changes in the DNA-synthesizing activity of lactotrophs in primary monolayer cultures of the rat anterior pituitary gland treated for 3 days with thyroliberin (TRH), somatostatin (SRIF) and bromocriptine (CB 154). The number of lactotrophs labelled with 3H-thymidine within the total pool of labeled pituitary cells was used to estimate DNA synthesis in prolactin-producing cells. TRH (10 ng/ml) stimulated DNA synthesis in the whole population of cultured cells but not in lactotrophs. TRH only weakly counteracted the noticeable inhibitory effect of CB 154 (0.75 microM/l) on thymidine incorporation into lactotrophs. SRIF (20 ng/ml) inhibited DNA synthesis in lactotrophs to a lesser extent than CB 154. The combination of methods used in this paper may be useful for studying the selective effects of regulators on the proliferative activity of various pituitary cell types in vivo and in culture.  相似文献   

9.
Intermittent high altitude (IHA) hypoxia (7000 m) increased the wet weight of the right ventricular myocardium of 30-day-old rats after two 4 h/day exposures. During the same period the number of DNA-synthesizing nuclei of both muscle and non-muscle cell types increased proportionally. After 4 such exposures to hypoxia the number of 3H-thymidine-labelled nuclei in both cell types increased further. In addition, the number of labelled nuclei increased significantly in the yet un-enlarged left ventricle. While there was no difference in the number of DNA-synthesizing cells between the right and left ventricles in control animals, a significant increase in the number of cells involved in DNA synthesis in the right ventricle was found in both groups of animals exposed to IHA hypoxia. These results show that DNA synthesis in myonuclei of the ventricular myocardium can be stimulated in 30-day-old rats, i.e. at the very end of the weaning period.  相似文献   

10.
The effect of antigenic bacterial lysate IRS-19 on the recovery of blood cells was studied in mice injured by a single dose of 7 Gy irradiation. The preirradiation administration of IRS-19 accelerated the recovery of leukocytes, reticulocytes and platelets in peripheral blood. The recovery of leukocytes 9-14 days after irradiation in protected animals was accompanied by a higher level of band forms of granulocytes as well as activated lymphoid and monocytoid cells.  相似文献   

11.
Anaemia is a widespread problem especially in the tropics. Among adolescent girls, it has negative consequences on growth, school performance, morbidity and reproductive performance. A cross-sectional study was conducted to investigate the prevalence of anaemia, iron, folate, zinc and copper deficiencies amongst adolescent schoolgirls in New Halfa, eastern Sudan, and to examine the relationship of these micronutrients with haemoglobin (Hb) levels. Out of 187 adolescent schoolgirls, 181 (96.8%) had anaemia (Hb?<?12 g/dl); 21% had mild anaemia (Hb 11.0–11.9 g/dl); 66.8.1% had moderate anaemia (Hb 8.0–10.9 g/dl), and 12.1% had severe anaemia (Hb?<?8 g/dl), respectively. Iron deficiency (S-ferritin?<?12 μg/l), iron deficiency anaemia (<12 m/dl and S- ferritin?<?12 μg/l) and folate deficiency (S-folate?<?3 ng/ml) were prevalent in 17.6%, 16.5% and 69% of these girls, respectively. Nine percent and 5.9% of these girls had zinc (<75 μg/ml) and copper deficiency (<75 μg/ml), respectively. Twenty-six (14%) girls had ≥2 micronutrient deficiencies. S-ferritin and zinc were significantly lower in patients with severe anaemia. Haemoglobin levels were significantly positively correlated with zinc levels (r?=?0.161, P?=?0.03) and with copper levels (r?=?0.151, P?=?0.03). Thus, interventions are required to prevent and control anaemia in this setting. Further research is needed.  相似文献   

12.
Anaemia is a widespread problem in many parts of the world especially in tropic areas. Among pregnant women, it has negative consequences on maternal and perinatal outcomes. A cross-sectional study was conducted to investigate the prevalence of anaemia, iron, zinc and copper deficiencies among pregnant women in Wad Medani hospital, central Sudan and to examine the relationship of these micronutrients with haemoglobin (Hb) levels. One hundred four (52.5%) out of 200 pregnant women had anaemia (Hb < 11 gm/dl) and 3 (1.5) % had severe anaemia (Hb < 7 gm/dl). Iron deficiency (S-ferritin < 15 μg/l), iron deficiency anaemia (<11 gm/dl and S-ferritin < 15 μg/l) were prevalent in 25 (12.5%) and 13 (6.5%) of these women, respectively. Ninety (45.0%) and eight (4.0%) of these women had zinc (<80 μg/ml) and copper (<80 μg/ml) deficiency, respectively. In 24 (12.0%) of these women, there were ≥2 deficiencies of these elements. S-copper was significantly lower in patients with anaemia. While age, parity, gestational age, ferritin, zinc and copper were not predictors for anaemia, women who practiced pica were at higher risk for anaemia (OR = 3.4, 95% CI = 1.4–7.9, P = 0.004). Gestational age was significantly inversely correlated with haemoglobin (r = 0.161, P = 0.03), S-ferritin (r = 0.285, P = 0.001) and S-zinc (r = 0.166, P = 0.02). Thus, dietary and supplement interventions are required to prevent and control anaemia in this setting. Further research is needed.  相似文献   

13.
The number of DNA-synthesizing lymphocytes in the phytohemagglutinin (PHA)-stimulated cultures of the peripheral blood of schizophrenic patients was determined. Under the mentioned conditions the number of DNA-synthesizing lymphocytes of the schizophrenic patients was 18% less than in the cultures of healthy donors. When the PHA-treated lymphocytes of normal donors were incubated with the serum of schizophrenic patients the number of lymphocytes capable of synthesizing DNA in the presence of PHA fell by 21%.  相似文献   

14.
目的分析鼻咽癌患者外周血循环内皮细胞(CECs)的水平及临床意义。 方法选取2016年1月至2018年10月期间于陆军军医大学第二附属医院接受单纯放疗或同期放化疗的55名初诊鼻咽癌患者为研究对象,归为鼻咽癌组,并随机选取同期来医院进行体检的50例健康成人为对照组。比较两组外周血CECs水平,并分析鼻咽癌组不同临床病理资料患者的外周血CECs水平,以及治疗前后的外周血CECs水平变化。根据疗效分为完全缓解(CR)组和未完全缓解组(包括部分缓解、疾病稳定和疾病进展)。两组间比较采用两样本t检验;计量资料采用百分比表示,比较采用χ2检验。 结果鼻咽癌组患者治疗前的外周血CECs水平为(21.13±8.33)个/μl,高于对照组的(5.03±2.25)个/μl,差异有统计学意义(t = 13.230,P < 0.01)。鼻咽癌组治疗前的外周血CECs水平T3~T4期(23.23±8.09)?个/μl高于T1~T2期(16.01±5.22)个/μl,差异具有统计学意义(t = 3.290,P < 0.01);N1~N3期(22.82±8.16)?个/μl高于N0期(15.06± 3.98)个/μl,差异具有统计学意义(t = 3.176,P < 0.01);M1期(28.30±3.33)?个/μl高于M0期(19.91±8.23)?个/μl,差异具有统计学意义(t = 2.826,P < 0.01);Ⅲ~Ⅳ期(23.26±7.93)个/μl高于Ⅰ~Ⅱ期(17.93±5.63)?个/μl,差异具有统计学意义(t = 2.726,P < 0.01)。CR组患者治疗前(20.03±8.12)?个/μl、治疗后3个月(12.61±5.33)?个/μl的外周血CECs水平低于未完全缓解组(26.75±3.29)?个/μl、(19.03±2.62)?个/μl,差异具有统计学意义(t = 5.181、5.507,P均< 0.01)。 结论鼻咽癌患者的外周血CECs水平明显升高,与病情进展、放化疗效果有关,可能成为潜在的肿瘤标志物。  相似文献   

15.
The ability of protaglandins E1 and E2 to stimulate the proliferation of haemopoietic stem cells (CFUs) was studied in vivo. PGE2, in a dose range of 10-4 to 10-1μg/g body weight and PGE1 in a dose range of 10-5 to 10-1μg/g body weight, produced a rapid cycling wave of CFUs. The increase in the number of CFUs in S phase was not followed by a rise in the femoral CFUs content, and except for a transient increase in femoral CFUc level, no increase in differentiation was found either. Therefore, it is proposed that haemopoiesis after PG-induced CFU stimulation is ineffective. PGE2 did not stimulate regeneration of CFUs in a perturbed state (after sublethal irradiation). All these findings support the idea that PGEs might represent potent stimulators of the haemopoietic stem cells acting in physiological doses. However, if acting concurrently with physiological control systems PGs lead to ineffective haemopoiesis (under normal conditions) or do not exert any measurable effect (after sublethal irradiation).  相似文献   

16.
In 21 patients with chronic lymphocytic leukemia (CLL) and in 8 hematologically normal persons the number of DNA-synthesizing peripheral blood lymphocytes was investigated by autoradiographic techniques. The lymphocytes were differentiated by EN-rosette tests into T and non-T lymphoid cells. The results show a normal number of proliferating T lymphoid cells and an increased number of proliferating non-T lymphoid cells in clinical stages O-I. Stages III-IV demonstrate a significant increase of the proliferation rate of both T and non-T lymphoid cells. The possible pathogenetic factors and the prognostic value of these results are discussed.  相似文献   

17.
Ultrastructural and functional studies were carried out on nurse shark (Ginglymostoma cirratum) peripheral blood cells in order to identify cells of definitive morphology and specific function. Along with erythrocytes and thrombocytes, four morphologically distinct leucocytes are recognized in peripheral blood: two types of granulocytes, the ‘eosiniphil’ and the ‘granulocyte’, and two mononuclear agranulocytic cells, one resembling mammalian macrophage and monocyte, the other resembling mammalian lymphocyte. Also present in peripheral circulation are blast-like cells and mitotic cells. In vitro phagocytosis was demonstrated by the monocyte-macrophage and the granulocyte while thrombocytes, eosinophils and lymphocytes showed no phagocytic activity in the system studied. It is stressed that care must be used in drawing functional analogies between blood cells of a mammal and an elasmobranch on the basis of morphological similarity alone.  相似文献   

18.
The marrow is a tissue distributed in numerous skeletal parts and works as an organ which is composed of a haemopoietic cell parenchyma and a supporting stroma. The pathophysiological mechanisms involved in the radiation-induced late effects depend mainly on the damage produced to each of these elements. Parenchymal cell damage ends with a failure of the stem cell pool to supply an adequate number of highly differentiated functional blood cells and is clinically manifested as aplastic anaemia or leukaemia. The effects of radiation on the haemopoietic stem cell can be measured by means of spleen colony forming units (CFU-S) in rodents. The self-maintaining capacity of the CFU-S was found to be lower than normal 16 weeks after a dose of 0.64 Gy. In larger animals it is only possible to measure the activity of some of the progenitor cells, estimating the number of granulocyte-macrophage colonies in culture (CFU-GM) as an indicator of stem cell changes. Their number in the blood is about 50 per cent of normal even 160 days after about 0.78 Gy. The stromal cells are also radiosensitive if measured with respect to their capacity to support long-term cell replication in vitro. Marrow fibrosis develops after single, repeated and chronic radiation exposure, and a dose of 40 Gy impairs the capacity of the marrow to support haemopoiesis.  相似文献   

19.
Abstract. Cyclic haemopoiesis in Grey Collie dogs is characterized by stable oscillations in all haemopoietic lineages. It is proposed that in these animals, in contrast to normal animals, the maturation process of haemopoietic (in particular granuloid) cells from the primitive progenitors to the functional cells is characterized by an abnormally strong synchrony. It is conjectured that the marrow maturation time has a very small variance compared with non-cyclic normal dogs. With a mathematical model of haemopoiesis it is shown that small fluctuations are amplified via regular feedback processes such that stable granuloid oscillations are established. Erythroid oscillations are induced indirectly by granuloid feedback to the stem cell pool. The model calculations further show that the synchrony hypothesis of bone marrow maturation can quantitatively explain the following experimental results: (1) the maintenance of stable cycles of granuloid and erythroid bone marrow and blood cells with a period of approximately 14 d; (2) the disappearance of granuloid and erythroid cycles during the administration of the colony stimulating factor rhG-CSF; (3) the reappearance of oscillations when the administration of CSF is discontinued; (4) the cessation of cycles during endotoxin application; and (5) the persistence of cycles during erythroid manipulations (bleeding anaemia, hypoxia, hypertransfusion). We therefore conclude that cyclic haemopoiesis is not caused by a defect in the regulatory control system but by an unusual maturation process.  相似文献   

20.
A study was made of the effect of injection of cyclophosphamide (CP) immunomodulating to BALB/c mice, according to 3 schemes of injection with the whole dose being 200 mg/kg. In all, the state of peripheral blood and spleen, the cellular content of lymph nodes and the number of DNA-synthesizing cells in them were studied, in addition to the ability of lymph node lymphocytes to proliferative reaction on T and B cells mitogens in vivo. It was determined that a 2-fold injection of CP, in contrast to 10- and 5-fold injections, resulted in splenomegaly and leukocytosis in the experimental animals. By means of quantitative tests in vivo, in was demonstrated that the dynamics of restoration of proliferative responses to mitogens depends on the CP injection scheme. These tests proved to be more informative for registration of immunomodulating effect of CP, than the study of cellular content of lymph nodes and the number of DNA-synthesizing cells in them.  相似文献   

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