RENEWAL OF GOBLET AND PANETH CELLS IN THE SMALL INTESTINE

Single and repeated injections of ³H-thymidine were used to demonstrate that both Paneth and goblet cells in the small intestine of the rat undergo renewal but do not themselves proliferate. Goblet cells are renewed much faster than Paneth cells and probably migrate with the columnar cells from the crypts to the villi. Attempts were made to identify the proliferative precursors.     

ON THE SITE OF SULFATION IN COLONIC GOBLET CELLS

The location of bound S³⁵ in the goblet cell of the rat colon at time points from 2 to 60 minutes after administration of S³⁵ as sodium sulfate has been observed in vivo and in vitro by radioautographic techniques. Grains were first observed by electron microscopy over the stacked lamellae of the paranuclear part of the Golgi apparatus. The label was subsequently found associated with the supranuclear Golgi lamellae and was then seen associated with the smooth membranes limiting the mucin granules in the goblet. Finally, between ½ and 1 hour, the secreted mucus product in the crypts became radioactive. Neither mitochondria nor the endoplasmic reticulum was labeled. It is concluded that the Golgi apparatus is the organelle in which sulfation occurs.     

CONTROL OF EPITHELIAL CELL PROLIFERATION IN THE SMALL INTESTINAL CRYPT

A heat labile factor which has been shown to inhibit proliferative activity in crypt epithelium both in rat jejunum in vivo and in explants of rat jejunum maintained in organ culture has been prepared from the soluble fraction of homogenized epithelial cells isolated from rat small intestinal crypts. The factor appears to have tissue specificity, for it has no influence on epithelial cell proliferation in colonic crypts, oesophagus or skin. Extracts of rat intestinal villous cells prepared using identical techniques were without effect on proliferative activity of small intestinal crypt epithelium.
Isoprenalin, which was also found to suppress cell proliferation, did not potentiate the effect of the factor and its effects were evanescent.     

THE INFLUENCE OF ADRENORECEPTOR ACTIVITY ON CRYPT CELL PROLIFERATION IN THE RAT JEJUNUM

The influence of adrenergic stimulation, adrenergic blockade and sympathectomy on crypt cell cycle time and mitotic time in rat jejunum was studied. Alpha adrenergic stimulation by noradrenaline was found to shorten both cell cycle and mitotic times, whereas beta adrenergic stimulation by adrenaline or isoprenaline was found to prolong both cell cycle and mitotic times. Conversely, alpha adrenergic blockade by phentolamine prolonged cell cycle time and beta adrenergic blockade by propranolol or practolol shortened cell cycle time but not mitotic time. Both chemical and surgical sympathectomy inhibited crypt cell proliferation. Chemically sympathectomized animals manifested supersensitivity to exogenous noradrenaline.     

AN ELECTRON MICROSCOPE STUDY OF MATURE AND DIFFERENTIATING PANETH CELLS IN THE RAT, ESPECIALLY OF THEIR ENDOPLASMIC RETICULUM AND LYSOSOMES

In an electron microsope study, the morphology of mature Paneth cells from the small intestine of adult rats is compared with that of differentiating Paneth cells from young rats 2 to 4 weeks old. All mature cells exhibit a marked polarity similar to that of other exocrine gland cells and contain a well developed endoplasmic reticulum, an elaborate Golgi complex, and numerous large secretory granules; they also possess an abundance of lysosomes. The most conspicuous occurrence in the process of differentiation is the development of the endoplasmic reticulum. The most immature Paneth cells possess an endoplasmic reticulum of the vesicular type, which, during maturation, is replaced by the characteristic lamellated ergastoplasm of the mature cell. At a certain stage of differentiation the cavities of the developing cisternae show numerous communications with the perinuclear space, suggesting an outgrowth of the ergastoplasm from the nuclear envelope. Furthermore, the cavities and the perinuclear space at this particular stage contain a material which shows a remarkable intrinsic periodicity. An identical periodicity was exhibited by material contained in Golgi cisternae and secretory granules. Lysosomes are also present in the differentiating cells.     

EFFECT OF VILLUS LENGTH ON CELL PROLIFERATION AND MIGRATION IN SMALL INTESTINAL EPITHELIUM

For the interpretation of data supporting the hypothesis of a feedback regulation of proliferative activity in intestinal crypts by the functional villus cell compartment the life span and migration rate of epithelial cells on villi of experimentally reduced length should be known. Autoradiographic studies and scintillation counting of isolated villi at different time intervals after ³H-thymidine labelling were carried out 36, 48 and 60 hr intervals after X-irradiation. The results showed that the life span of epithelial cells in rat small intestine (36–48 hr) is independent of the villus length. In villi of reduced length the migration rate of the epithelial cells was found to be decreased compared with controls. Changes in the migration rate in turn seem to be dependent on the production of epithelial cells in the crypt. Comparative studies on the recovery of crypt and villus epithelium after various doses (300 and 700 R) of X-radiation support the hypothesis that increased proliferative activity in the crypt cell compartment is related to a reduction of the number of functional villus cells below a critical villus length. The importance of these findings in the interpretation of data on (micro) biochemical analyses of certain cell differentiation characteristics during increased proliferative activity is discussed.     

枯否细胞在实验性肝癌细胞凋亡中的作用研究

探讨Kupffer细胞在大鼠实验性肝癌细胞凋亡中的作用。应用免疫组化方法和TUNEL法对单用二乙基亚硝胺（DENA）诱发的肝癌及用氯化钆（GC）或酶母多糖（ZM）分别阻塞或激活Kupffer细胞后,给以DENA所引起的大鼠肝癌中的增殖细胞核抗原（PCNA）、bax、bcl-2蛋白表达和肝癌细胞的凋亡进行了对比研究,结果显示：肝癌组织的增殖指数在ZM＋DENA组、DENA组、GC＋DENA组依次增高,而凋亡指数在上述各组依次降低。Bax阳性率在ZM＋DENA组明显高于DENA组（P＜0.05）,而ZM＋DENA组bcl-2阳性率明显低于DENA组（P＜0.05）。结果提示：Kupffer细胞可促进实验性肝部细胞凋亡。     

THE INFLUENCE OF DIETARY PROTEIN DEFICIENCY ON HAEMOPOIETIC CELLS IN THE MOUSE

These experiments examined the effect of a diet limited only in protein (4% by weight) on haemopoietic stem cells in mice. This diet places severe restrictions on growth and cell proliferation and this was reflected in lower numbers of colony forming units (CFUs) and in vitro colony forming cells (CFCs). Differences were apparent in the response of different organs to this stress; for instance, the incidence of spleen CFUs fell sharply from around 40/mg spleen tissue to 1 -4/mg spleen tissue after 3 weeks on a low protein diet. This selective loss did not occur in bone marrow where total CFUs remained proportional to cellular content. Yet a third pattern was shown by thymus CFUs–although the numbers were low these increased from 16/thymus in normal mice to 132/thymus in deprived mice. This was the only organ examined which showed an increase. The effects of a return to a high protein (18 %) diet showed that the spleen was the most responsive organ. By day 5 after the return to 18% protein the spleen contained as many CFUs per million cells as the bone marrow. During this time the content of CFU in the spleen had increased some 50-fold whereas bone marrow CFUs only doubled. The spleen assumes the major reconstitutive role during the refeeding process.     

小麦及缺体小麦与黑麦杂种幼胚愈伤组织在长期继代中的染色体数量变异

对中国春及其６Ａ缺体与黑麦杂种幼胚愈伤组织在长期继代培养过程中愈伤组织的染色体数量进行了统计分析,结果表明：中国春×黑麦和６Ａ缺体×黑麦杂种幼胚愈伤组织在继代培养的前６０ｄ内细胞染色体数目分别稳定在２ｎ＝２８和２７;随着继代培养时间的延长,其染色体数量均发生变异主要表现为染色体数的减少;在第４２０ｄ至５４０ｄ培养期间两个组合愈伤组织丢失染色体的细胞比率明显增加,同时也发现了个别超出正常染色体数的细胞。第５４０ｄ后的愈伤组织染色体数量变异基本维持在这一水平。     

高氏后异刺线虫肠道和生殖细胞超微结构观察

我们曾经发现雌性高氏后异刺线虫在生殖周期中,虫体的外表形态和器官结构以及细胞核内DNA含量均发生连续的变化。现在进一步对线虫细胞的超微结构进行分析,着重观察核内染色质结构的变化。前三期雌虫肠细胞核内有许多粗大的染色质团块和显著的核仁。Ⅳ期肠核内染色质团块融合成少数球体,而且不断减少,以致消失,单剩下染色质细粒(纤丝切面)。而核仁增大,结构更为复杂。卵巢细胞亦有类似改变,但末见染色质球体。雄虫并无生殖周期,也无上述变化。     

THE RELATIONSHIP BETWEEN DIURNAL VARIATION OF THE NUMBER OF CELLS IN MITOSIS AND OF THE NUMBER OF CELLS SYNTHESIZING DNA IN THE EPITHELIUM OF THE HAMSTER CHEEK POUCH

1. The numbers of cells in mitosis and in DNA synthesis in the epithelium of the hamster cheek pouch have been studied at different times of the day and night. 2. By accumulation of mitotic cells using colcemid, both the rate of entry of cells into mitosis and the duration of mitosis have been estimated at two different times of day. 3. A diurnal variation has been demonstrated in both the mitotic index and in the tritiated thymidine labelling index. Although these variations are of different amplitude and timing, the experimental data fit closely to the hypothesis that the diurnal mitotic variation is the result of a partially synchronous population moving through the DNA synthetic period. No direct action on the mitotic process need be postulated. 4. From the results of mitotic accumulation, it is clear that the rate of entry of cells into mitosis depends on the time of day at which this is studied. There is also the possibility that the duration of mitosis is slightly longer when the mitotic index is high. 5. It is concluded that, at least in the epithelium of the hamster cheek pouch, the diurnal rhythm in the number of mitoses present is a reflection of the diurnal variation in the number of cells synthesizing DNA at some time earlier. Small fluctuations in the mitotic pattern imposed by this partially synchronous population moving from S into mitosis, could be caused by slight variations in the duration of mitosis.     

AN ELECTRON MICROSCOPE STUDY OF THE EPITHELIUM IN THE NORMAL MATURE AND IMMATURE MOUSE CORNEA

1. An electron microscope study at high resolution of the corneal epithelium of the normal mature and immature mouse revealed new information regarding the submicroscopic appearance of these cells. 2. Two thin dense lines separated by a less dense area constituted the structure of the limiting surface membrane of epithelial cells; the thickness of this membrane was about 80 A. 3. Some differences in the appearance of the cytoplasm and mitochondria of cells from the immature mouse cornea and the appearance of the cytoplasm and mitochondria of cells from the adult mouse cornea were observed. 4. The basement membrane appeared as a dense band about 600 A wide separating the basal epithelial cells from the substantia propria. Suggestions of periodicity were seen in some phosphotungstic acid-treated specimens. 5. Round bodies believed to be bacteria were seen on the surface of the outer epithelial cells in the adult mouse cornea but not in the immature, unopened eye.     

南方鲇消化道杯状细胞分布及类型探讨

本研究应用阿利新蓝－过碘酸雪夫氏（ＡＢ－ＰＡＳ）染色方法对南方鲇（Ｓｉｌｕｒｕｓ　ｍｅｒｉｄｉｏｎａｌｉｓ）消化道杯状细胞的分布特点进行了分类研究,结果表明：南方鲇消化道杯状细胞的数量从肠前段、肠中段到肠后段,呈现递增趋势,有杯状、囊状和梨形三种不同的形态,ＡＢ反应阳性,ＰＡＳ反应阴性,分泌物主要含酸性粘多糖,属Ⅱ型粘液细胞。     

男性不育患者精液生殖细胞微核率的观察

本文研究人类精液中幼稚生殖细胞的微核率和男性不育的关系。在31例病人中,11例为无精症或多精症患者,其精液缺乏幼稚生殖细胞而未能进行微核测定。在其余的20例中,微核率最高可达122‰,最低为16‰。其中9例的微核率与对照组相比有显著升高,高微核率往往还伴随有减数分裂不分离以及出现高比例的二倍体及四倍体精子。还讨论了生殖细胞微核率增高作为不育症的一个可能病因以及微核测定的临床使用价值。     

PHYLOGENETIC TRANSITIONS IN THE CHLOROPLASTS OF THE ANTHOCEROTALES I. THE NUMBER AND ULTRASTRUCTURE OF THE MATURE PLASTIDS

Representatives of three genera of anthooerotes were examined: Phaeoceros, Notothylas, and Megaceros. Species of the first two genera were found to exemplify the typical anthocerote plastid condition. This condition is characterized by the presence in each cell of the gametophyte of only a single large chloroplast containing a “multiple” pyrenoid. The genus Megaceros, however, proved to be quite different. In two species of Megaceros the pyrenoid was observed to be composed of a highly subdivided thylakoid system of even greater complexity than the “multiple” pyrenoids of Phaeoceros. In another species only an indistinct “pyrenoid-like” area was noted while in a fourth species no evidence was found for any internal differentiation. Associated with these changes in plastid structure there are corresponding alterations in the number and the size of the chloroplasts. Together they indicate an evolutionary trend away from a primitive, algal-like condition to a more advanced land plant form.     

电针对佐剂性关节炎大鼠病灶局部CRH阳性细胞免疫反应性的影响

目的研究电针对佐剂性关节炎大鼠的镇痛作用机制是否与其对病灶局部CRH阳性细胞免疫反应性的影响有关。方法本课题采用佐剂性关节炎模型大鼠,研究电针同侧环跳穴、阳陵泉穴对运动障碍的改善作用,采用免疫组化技术,观察电针对致炎后模型大鼠外踝关节周围皮肤及皮下组织CRH阳性细胞免疫反应性的影响,同时针刺非穴位和对侧穴位进行对照,探讨针刺作用的穴位特异性。结果造模后,除空白组外其他各组大鼠运动障碍明显,分别电针同侧及对侧穴位可显著改善炎症大鼠的运动障碍。炎症组病灶局部CRH阳性细胞的面积百分比、平均光密度均显著高于空白对照组,电针同侧穴位、对侧穴位显著降低炎症组CRH阳性细胞的平均光密度,而非经穴电针对照组没有显著疗效。结论电针同侧穴位、对侧穴位可通过促使定向迁移至炎性痛病灶的免疫细胞合成并释放CRH,从而发挥镇痛作用,与中医“巨刺法”的说法相呼应。