STUDIES ON THE HUMAN CORPUS LUTEUM : I. Observations on the Ultrastructure of Development and Regression of the Luteal Cells During the Menstrual Cycle

The ultrastructure of huma corpora luntea obtained approximately 2, 3, 5, 11, and 15 days after ovulation is reported. All specimens were fixed in Karnovsky's formaldehyde-glutaral-dehyde solution. The 5-day corpus luteum is presumed to represent, in terms of fine structure, the ultrastructural aspects of high progesterone production and is compared to younger differentiating and older regressing specimens. A distinct topographic relationship of cytoplasmic organelles is noted in the mature 5-day luteal cell. It consists of a peripheral cupshaped mass of tubular ER (endoplasmic reticulum), associated with granular ER, lipid droplets, and mitochondria, which merges with a large paranuclear Golgi area extending to a cell surface bordering a perivascular space. The plasma membrane of active luteal cells is described and its variations suggest areas of specialized surface activities. The prevalence and ultrastructure of more electron-opaque stellate cells, of phagocytes, and of thecal cells are reported.     

STUDIES ON THE HUMAN OOCYTE AND ITS FOLLICLE : I. Ultrastructural and Histochemical Observations on the Primordial Follicle Stage

Oocytes in primordial ("resting") follicles in adult human ovaries contain a complex paranuclear structure identified by light microscopists as Balbiani's vitelline body. By electron microscopy this structure is composed of a mass of mitochondria with associated endoplasmic reticulum, multiple compound aggregates which form a ring around the cytocentrum, and a single stack or coil of annulate lamellae either attached to the nuclear membrane or free in the cytoplasm. The compound aggregates contain vacuoles and finely divided electron-opaque material. Evidence is presented for the probable transport of this material between the oocyte and its environment. The cytocentrum contains a central aggregate of amorphous electron-opaque deposits which appear to become periodically aligned on fine fibrils to form the long coarse fibers at the periphery of the cytocentrum. The apparent prevalence of annulate lamellae attached or adjacent to the nuclear membrane of oocytes in ovaries removed during the mid-follicular (estrogenic) phase of the cycle indicates the need for further study of a possible hormonal influence on the resting oocyte. By light microscopy phosphatases were not found within the oocyte, but adenosine-monophosphatase activity is present in the cortical cells surrounding primordial follicles, and also at the periphery of each primitive follicle cell, most prominently at the oocyte side. Glucose-6-phosphate dehydrogenase activity is present within the oocyte cytoplasm.     

STUDIES ON THE STABILITY OF THE NORMAL HUMAN FECAL FLORA.

Zubrzycki, Leonard (Temple University, Philadelphia, Pa.) and Earle H. Spaulding. Studies on the stability of the normal human fecal flora. J. Bacteriol. 83:968-974. 1962.-The results of two series of stool cultures show that members of the genus Bacteriodes constitute the most numerous group of bacteria in the normal human adult fecal flora. Together with the enterococci, coliform bacilli, diphtheroids, and lactobacilli, these major components account for more than 99% of the total counts. Wide fluctuations in the number and types of minor organisms observed suggest the probability that they are held in check by these major components which may also possess mechanisms for preventing pathogens from establishing themselves in the large bowel.     

STUDIES ON CARTILAGE : II. Electron Microscope Observations on Rabbit Ear Cartilage following the Administration of Papain

Electron microscope observations on rabbit ear cartilage following the administration of papain show that both the elastic component of the matrix and the amorphous material disappear leaving a matrix which consists of delicate fibrils which are presumed to be collagen. This unmasking of fibrils coincides with the appearance of an abnormal component in the electrophoretic pattern of the rabbit's serum. The chondrocytes show vacuoles in their cytoplasm which appear at the same time that the cells appear crenated in the light microscope. A ruffly appearance of the cell surface membrane coincides with this vacuolization, and vacuoles often appear open and in continuity with the extracellular space. The resurgence of the rabbit ear is accompanied by a reconstitution of both the amorphous material and the elastic component of the matrix. During this period numerous dilated cisternae of the endoplasmic reticulum which contain a moderately dense material are present in the chondrocyte cytoplasm. We have been unable to demonstrate a direct relationship between the elastic component of the matrix and a particular component of the chondrocyte cytoplasm, but it is clear that changes occur in the cartilage cell cytoplasm during both the depletion and reconstitution of the matrix. Previous studies on the effect of papain on elastic tissue are noted and the possible relationships between changes in the cells and matrix of this elastic cartilage are discussed.     

中国假尾孢属的研究II．

本文报道中国假尾孢属的24个种,其中有2个新种:杨桐假尾孢(Pseudocercospora adinandrae Guo&Liu),钟萼假尾孢(Pseudocercospora bretschneiderae Liu&Guo),10个新组合,1个新名称:木豆假尾孢(Pseudoeercospora cajani-flavi Guo&Liu)和11个中国新记录。文中对2个新种提供了拉丁文简介、描述及图。所研究的标本全部保存在中国科学院微生物研究所真菌标本室(HMAS)。     

中国假尾孢属的研究Ⅱ.

本文报道中国假尾孢属的24个种,其中有2个新种:杨桐假尾孢(Pseudocercospora adinandrae Guo&Liu),钟萼假尾孢(Pseudocercospora bretschneiderae Liu&Guo),10个新组合,1个新名称:木豆假尾孢(Pseudoeercospora cajani-flavi Guo&Liu)和11个中国新记录。文中对2个新种提供了拉丁文简介、描述及图。所研究的标本全部保存在中国科学院微生物研究所真菌标本室(HMAS)。     

STUDIES ON DISPERSED PANCREATIC EXOCRINE CELLS : II. Functional Characteristics of Separated Cells

The functional characteristics of separated guinea pig pancreatic exocrine cells have been examined following dissociation of the gland by a procedure described in the previous paper (J. Cell Biol. 1974. 63:1037). The ability of isolated cells to incorporate labeled amino acids into secretory proteins was assessed biochemically and by quantitative electron microscope autoradiography. Incorporation remained linear for up to 4-h incubation at levels equivalent to those of pancreatic slices; over 95% of the exocrine cells in the population were viable, and all appeared to be equally active in incorporating amino acids. The capacity of separated cells to transport, concentrate, and store exportable proteins was monitored by electron microscope autoradiography on populations pulse labeled with [³H]leucine and chase incubated for 4 h. The same overall pathway previously mapped in pancreatic slices was followed by secretory proteins in separated cells although in quantitative studies a defect was noted in the rate of conversion of condensing vacuoles to zymogen granules. Secretogogue responsiveness was assessed by monitoring discharge of labeled secretory proteins or of amylase in response to carbamylcholine and caerulein to the medium. While the separated cells released secretory proteins linearly for up to 4 h in response to both secretogogues, the net release was ~50% less than previously noted for pancreatic slices and required a ten times higher concentration of stimulant. The defect may represent alteration in receptors due to the protease used for dissociation. Our data indicate, however, that separated exocrine cells retain their ability to process secretory proteins stepwise and vectorially which is consistent with preservation of structural polarity.     

STUDIES ON BIOLUMINESCENCE : II. THE PARTIAL PURIFICATION OF CYPRIDINA LUCIFERIN

Some solubility, oxidation, reduction, and compound-forming characteristics of extracts of Cypridina luciferin have been presented. A method of purification has been described which increased the amount of luciferin per unit of dry weight, as measured by the total light emitted, to about two thousand times that in the dry starting material. The best yields were from 50 to 65 per cent.     

STUDIES ON AMPHIBIAN YOLK : 1. The Ultrastructure of the Yolk Platelet

The yolk platelets of mature eggs and young embryonic cells of all amphibian species studied (Rana pipiens, Triturus pyrrhogaster, Diemictylus viridescens, Rana nigromaculata, and Bufo vulgaris) have a superficial layer of fine particles or fibrils (ca. 50 A in diameter), a central main body with a crystalline lattice structure, and an enclosing membrane approximately 70 A in thickness. Electron micrographs of the main body reveal hexagonal net (spacing ca. 70 A), square net (spacing ca. 80 A), and parallel band (spacing from 35 to 100 A but most frequent at ca. 70 A) patterns. The crystalline structure is believed to be a simple hexagonal lattice made of closely packed cylindrical rods. Each rod is estimated to be about 80 A in diameter and 160 A in length.     

STUDIES ON THE GIANT KELP,MACROCYSTIS. II. REPRODUCTION

Neushul , M. (U. Washington, Seattle.) Studies on the giant kelp, Macrocystis. II. Reproduction. Amer. Jour. Bot. 50(4): 354–359. Illus. 1963.—The reproduction of Macrocystis pyrifera was studied in the sea and in the laboratory. The estimated minimum time needed for the completion of the sexual life history of Macrocystis pyrifera in La Jolla, California, is from 12 to 14 months. Young sporophytes begin fruiting when they have from 4 to 8 stipes and a somatic frond weight of from 8 to 10 kg. The behavior of abscised sporophylls in laboratory tanks, as well as their morphology and coloration, strongly suggests an interrelationship between the translocation of photosynthetic products and fructification.     

STUDIES ON THE OXIDATIVE METABOLISM OF SACCHAROMYCES CEREVISIAE : I. Observations on the Fine Structure of the Yeast Cell

Vegetative cells of Saccharomyces cerevisiae were fixed with potassium permanganate followed by uranyl nitrate, embedded in methacrylate, and studied in electron micrographs of thin sections. Details of the structure of the cell wall, cytoplasmic membrane, nucleus, vacuole, and mitochondria are described. Cell membranes, about 70 to 80 A thick, have been resolved into two dense layers, 20 to 25 A thick, separated by a light layer of the same dimensions, which correspond in thickness and appearance to the components of the "unit membrane" as described by Robertson (15). The cell wall is made up of zones of different electron opacity. Underlying the cell wall is the cytoplasmic membrane, a sinuous structure with numerous invaginations. The nucleoplasm, often of uneven electron opacity, is enclosed in a pair of unit membranes in which nuclear pores are apparent. The vacuole, limited by a single unit membrane, is usually irregular in outline and contains some dense material. Rod-shaped mitochondria, 0.4 to 0.6 µ in length and 0.2 to 0.3 µ in diameter, are smaller in size, but similar in structure to some of those described in plant and animal cells. Attempts to use osmium tetroxide as fixative were unsuccessful, a result similar to that obtained by other workers. It is suggested that yeast cells are impermeable to osmium tetroxide, except when grown under specific conditions.     

中国星盾炱属分类研究Ⅱ．

本文报道了产于中国的星盾炱属Asterina L(?)v.23个种,其中2个新种和15个国内新记录种。新种是山芝麻星盾炱Asterina helicteris Y.S.Ouyang et Y.X.Hu和柄果木星盾炱Asterina mischocarpi Y.S.Ouyang et Y.X.Hu。标本保存于广东省微生物研究所(GDIM)。     

STUDIES ON THE METABOLISM OF AUTOTROPHIC BACTERIA : II. THE NATURE OF THE CHEMOSYNTHETIC REACTION

In a study of chemosynthesis (the fixation of CO₂ by autotrophic bacteria in the dark) in Thiobacillus thiooxidans, the data obtained support the following conclusions: 1. CO₂ can be fixed by "resting cells" of Thiobacillus thiooxidans; the fixation is not "growth bound." 2. The physiological condition of the cell is of considerable importance in determining CO₂ fixation. 3. CO₂ fixation can occur in the absence of oxidizable sulfur in "young" cells. The extent of this fixation appears to be dependent upon the pCO₂. 4. CO₂ fixation can also occur under anaerobic conditions and the presence of sulfur does not influence such fixation. 5. However, in the CO₂ fixation by cells in the absence of sulfur, only a limited amount of CO₂ can be fixed. This amount is approximately 40 µl. CO₂ per 100 micrograms bacterial nitrogen. After a culture has utilized this amount of CO₂ it no longer has the ability to fix CO₂ but releases it during its respiration. 6. Relatively short periods of sulfur oxidation can restore the ability of cells to fix CO₂ under conditions where sulfur oxidation is prevented. 7. It is possible to oxidize sulfur in the absence of CO₂ and to store the energy thus formed within the cell. It is then possible to use this energy at a later time for the fixation of CO₂ in the entire absence of sulfur oxidation. 8. Cultures of Thiobacillus thiooxidans respiring on sulfur utilize CO₂ in a reaction which proceeds to a zero concentration of CO₂ in the atmosphere. 9. CO₂ may act as an oxidizing agent for sulfur. 10. Hydrogen is not utilized by the organism. 11. It is possible to selectively inhibit sulfur oxidation and CO₂ fixation.     

STUDIES ON THE DIFFUSION EFFECT UPON IONIC DISTRIBUTION : II. EXPERIMENTS ON IONIC ACCUMULATION

The aim of this paper is to present confirmation of the theory of the diffusion effect. By diffusion effect is understood a redistribution of the ions in a system where a continuous diffusion of one electrolyte is going on, which results in a steady state showing accumulation and impoverishment of certain ions. Some typical experiments are recorded and discussed. The results are found in satisfactory agreement with the theory: this can be demonstrated in several ways. The importance of considering activity changes is pointed out. Water migration and the diffusion membrane probably have no appreciable influence upon the diffusion effect under the conditions of these experiments. The diffusion effect may have biological analogies.     

STUDIES ON LUMINOUS BACTERIA : II. THE INFLUENCE OF TEMPERATURE ON THE INTENSITY OF THE LIGHT OF LUMINOUS BACTERIA.

1. A method has been described whereby the intensity of the light of luminous bacteria may be measured in a quantitative manner. 2. It is pointed out that the temperature coefficients for light intensity do not follow the van''t Hoff rule, but are higher and vary with each 10° temperature interval. 3. From a comparison with other data it is found that the process is not a simple one, but that the observed curve is the resultant of several reactions which proceed simultaneously. 4. The discrepancies in the temperature coefficients in the neighborhood of the "optimum temperature" may be due to a process of coagulation of the colloidal particles of the enzyme. This coagulation will tend to cause a deviation of the curve away from that normal for chemical reactions.     

核黄素生物合成研究 1.微量培养中核黄菌(Eremothecium ashbyii)发育过程中的形态变化

从本试验观察到,核黄菌的生长全部过程是自配子或菌丝在培养基中开始发育成营养菌丝,部分菌丝形成配子囊形成配子,部分菌丝衰老自溶。当菌丝发育最盛时,核黄素的形成是最多,衰老时培养基核黄素逐渐丰富起来。核黄菌在有空气和缺乏空气时,它们的发育是有区别的,即是在缺乏空气(表面下生长)时,菌丝是细长不形成配子和产生少量核黄素。