Renal Function in Dogs With Pyometra

Renal function studies on bitches with pyometra and normal bitches have included determinations of glomerular filtration rate (GFR), effective renal plasma flow (ERPF), solute excretion rate per unit functioning renal mass, maximum urine osmolarity (max. Uosm), and — for the normal bitches — max. Uosm after increasing osmotic load with mannitol infusions. GFR for the pyometra bitches varied from normal to greatly reduced values; the mean GFR was statistically significantly lower than that for normal bitches. There were also wide variations in ERPF; there was no significant deviation from normal values but the two pyometra bitches with the greatest reduction in GFR also had greatly reduced ERPF values. The ratio between GFR and ERPF (filtration fraction) varied within normal limits but there was a tendency towards reduction (0.05 < P < 0.01). After dehydration the max. Uosm for all the pyometra bitches was below the lower limit for max. Uosm for normal bitches. The rates of solute excretion per unit functioning renal mass for most bitches with pyometra were less than the level (468 µ Osm/min./100 GFR) above which the osmotic load begins to reduce max. Uosm in normal bitches. Even in those bitches in which the solute excretion rate reached values over 468 µOsm/min./100 GFR (because of reduction in the number of functioning nephrons) max. Uosm was far below the max. Uosm values for normal dogs at the same rates of solute excretion. Consequently, in bitches with pyometra, factors other than osmotic diuresis appear to be mainly responsible for the reduction in concentrating ability and polyuria.     

Comparative Pathophysiological Aspects of the Glomerulonephritis Associated With Pyometra in Dogs

This report deals with some clinical features of bitches with pyometra accompanied by polyuria. According to previous morphological studies a glomerulonephritis often acompanies pyometra in bitches. The renal dysfunction of pyometra has been compared with observations made on human beings with morphologically similar nephropathies. Reduction of the glomerular filtration rate and filtration fraction, the occurrence of proteinuria, and hypercholesterolaemia are clinical features in common. The reduced concentrating ability of pyometra bitches — probably the result of toxin released from the uterus — gives polyuria, a clinical sign which does not appear in human beings with glomerulonephritis. Other differences are the absence of oedema and hypertension in pyometra bitches. These differences do not necessarily imply a difference in the nature of the renal damage; they more likely represent species differences in reaction patterns. Possible causal relationships between the different functional abnormalities and between the functional abnormalities and the morphological changes are discussed.     

Scanning Electron Microscopical Studies of Developing Gustatory Papillae in Humans

Development and morphological changes of human gustatory papillaeduring postovulatory weeks 6–15 have been studied usingscanning and transmission electron microscopy. The first papillaof the tongue appears around postovulatory week 6 in its caudalmidline near the foramen caecum. In contrast, the dorsal epitheliumof the anterior part of the tongue shows only small hillock-or papilla-like elevations from week 6 on, which comprise anaggregation of 5–20 epithelial cells. From week 7 on,most prominent fungiform papillae develop near the median sulcusand at the margins of the anterior part of the tongue. At theirtops, the first primitive taste pores are found around week10; these are often covered with processes of adjacent epithelialcells. Most pores, however, develop around weeks 14–15.The maturation of taste buds does not coincide with the appearanceof taste pores, since taste bud cells are not fully differentiatedin the observed period of time. Fungiform papillae are developedbefore filiform papillae, which do not occur within the first15 weeks of gestation. Fungiform papillae tend to grow betweenweeks 8 and 15 of gestation, whereas the size of vallate papillaeseems to be constant during this period. Chem. Senses 22: 601–612,1997.     

Light Microscopical Studies on Salt Gland Development in Tamarix aphylla L

Young branches and leaves of Tamarix aphylla L. have many epidermalsalt glands, and each salt gland originates from a single protodermalcell which divides anticlinally to give rise to two equally-sizeddaughter cells. The latter further undergo two successive asynchronous,asymmetrical divisions resulting in the formation of six, denselycytoplasmic, secretory cells. In the next developmental stage,two inner, vacuolated parenchyma cells adjacent and adherentto the inner secretory cells progressively transform to whathave been termed in the literature the collecting cells of theglands. Thus, it appears at maturity that the glands consistof eight cells, and all eight cells may be directly involvedin the secretory process Tamarix aphylla L., alt gland, development     

Light and Electron Microscopical Observations on the Stomatogenesis of the Ciliate Coleps amphacanthus Ehrenberg, 1833

Light and electron microscopical observations on the stomatogenesis of Coleps amphacanthus Ehrenberg, 1833, show that this "gymno"-stome ciliate has a well developed oral ciliature made of 19–23 "paroral dikinetids" and three "adoral organelles." These structures were previously known as "circumoral ciliature" and "dorsal brosse," and it was thought that they originated from the distal ends of all the 22–26 somatic kineties. Contrary to this view, only four stomatogenic kineties (K1, Kn, Kn-1, and Kn-2) are involved in stomatogenesis of the opisthe. All paroral dikinetids arise from one single kinetofragment (KF1) to the right of the oral anlage while the adoral organelles originate from the three left kinetofragments (KFn, KFn-1, and KFn-2). In particular, the future paroral dikinetids perform a complex morphogenetic movement that leads to a situation where the postciliary microtubules of the once posterior kinetosome of each oral dikinetid give rise to the cytopharyngeal microtubular ribbons. The postciliary origin of the cytopharyngeal ribbons which could only be detected by an EM study of stomatogenesis shows that the basket of Coleps belongs to the cyrtos-type and not to the rhabdos-type basket, where transverse microtubules accompany the basket-forming nematodesmata. The taxonomic implications of these observations, which may lead to a revision of the systematic position of the genus Coleps , are discussed.     

波纹唇鱼鳃丝的光镜、扫描和透射电镜观察

应用光学显微镜、扫描电镜和透射电镜对波纹唇鱼(Cheilinus undulatus)鳃的组织结构、表面形态特征及鳃小片超微结构进行了观察.结果表明,波纹唇鱼有3对全鳃,1对半鳃和1对伪鳃,鳃丝呈梳状紧密排列在鳃弓上,鳃小片紧密地镶嵌排列在鳃丝两侧,入鳃动脉、出鳃动脉和鳃小片毛细血管网组成鳃的血液系统.鳃丝非呼吸区分布...     

中国大鲵肺脏的显微和超微结构

中国大鲵Andrias davidianus Blanchard,1871属于两栖纲有尾目隐鳃鲵科,是地球现存个体最大的两栖动物。大鲵在我国分布广泛（侯进慧等,2004）,是由水生脊椎动物向陆生脊椎动物过渡的类群,因此是研究动物进化的好材料。目前,有关大鲵内脏器官的组织形态学及结构方面的研究已有一些报道（霍军,程会昌,2003;方展强,2006）,本文报道对其肺脏超微结构的研究。     

Light and Electron Microscope Studies of Some Annelid Setae

An account of a light and electron microscope study of the setae of Disoma multisetosum, Pectinaria belgica (Polychaeta sedentaria) and Echiurus echiurus (Echiuroidea) is given. The results are compared with those of previous researchers, and the possibility of using the ultrastructure of the “annelid seta” as a phylogenetic-systematic instrument is preliminarily discussed.     

The Pineal Gland of the Mink, Mustela vison: Light-, Fluorescence- and Electron Microscopical Studies

The pineal gland of normal and experimental female mink has been studied by light-, fluorescence- and electron microscopy. The general structure of the mink pineal is described. Two main cell types are recognized. One, termed pinealocyte, predominates in number. Though slight morphological differences (e.g. electron density of the cytoplasm and content of organelles) were observed, this study indicates that the pineal of mink only contains one single population of pinealocytes. The other, termed glial cell, inserted between the pinealocytes, is characterized by the presence of elongated processes, containing microfilaments. Different treatments (ovariectomy and LH—RH administration) and different endocrine states during the year induced morphological changes in the pinealocytes. A rich network of nerve fibres containing electron-dense granules (40–50 nm) is observed. Microspectrofluorometrically these fibres exhibit the spectral characteristics of cateholamines. All the pinealocytes show a yellow fluorescence. This cellular fluorophor shows the same microspectrofluorometric characteristics as does the fluorophor of serotonin. Occasionally, synaptic ribbons are observed in the perikaryon and the processes of the pinealocytes. A large number of cellular junctions between pinealocytes and endothelial cells is present. Their presumed function(s) are discussed. There is evidence of a blood-brain barrier within the mink pineal gland.     

珠江口池养梭鱼鳃的光镜、扫描和透射电镜观察

应用光学显微镜、扫描电镜和透射电镜对珠江口池塘养殖梭鱼Liza haematocheila鳃的组织结构、表面形态特征及鳃小片超微结构进行了观察。结果表明梭鱼具有4对鳃,每个鳃由鳃弓、鳃丝、鳃小片和鳃耙组成。梭鱼鳃丝和鳃小片的表面结构和超微结构与其他硬骨鱼类的基本相似,鳃丝表面分布有众多规则或不规则的环形微嵴、沟、坑、孔等结构。鳃丝分为呼吸区和非呼吸区,呼吸区较为平滑,上皮细胞表面无微嵴,呈皱褶状;非呼吸区分布有沟、坑、孔等结构,上皮细胞有较规则的指纹状微嵴。鳃小片是最主要的呼吸场所,由基膜、上皮细胞、内皮细胞、柱细胞和毛细血管网组成。泌氯细胞主要分布在鳃小片基部,并有开口通往外界。本文还探讨了梭鱼鳃的结构与其功能的密切关系。     

Light and Electron Microscopical Characterization of Heterophilic Granulocytes in the Intestinal Wall and Islet Parenchyma of the Hagfish,Myxine glutinosa (Cyclostomata)

Heterophilic granulocytes were studied in the blood, intestinal wall, and islet parenchyma of the Atlantic hagfish (Myxine glutinosa) by light and electron microscopical methods. The granulocytes are pseudoeosinophils and show a PAS-positive cytoplasmic reaction. Ultrastructurally, the cells contain evenly distributed pleomorphic cytoplasmic granules with the granule membrane close to the osmiophilic core. Emigrated blood granulocytes are found extra-vascularly in the submucous connective tissue, and obviously they can pass the basal lamina and migrate into the epithelium of the intestine, bile duct, and islet parenchyma. Though the staining characteristics of hagfish granulocytes are different from those of endocrine cells in the intestinal mucosa and islet parenchyma, intraepithelial granulocytes in some locations may sometimes be difficult to distinguish ultrastructurally from insulin-containing B-cells, since heterophil granules have both a size and a shape close to those of secretion granules in B-cells. However, in contrast to B-cells the granulocytes show the following ultrastructural features: a lobated nucleus with peripherally arranged electron-dense chromatin; cytoplasmic processes and often rod-like granules with no clear space between the granule membrane and core; prominent cytoplasmic vacuoles and microtubules; and sparse mitochondria and endoplasmic reticulum. Furthermore, immigrated granulocytes lack desmosomes and annulate lamellae. Some of the intraepithelial granulocytes in the mucosa show signs of disintegration and cell death. Degenerative cell processes are also described in the islet parenchyma.     

A Light and Electron Microscopical Study of Trichoduboscqia epeori Léger (Microspora: Duboscqiidae)1

Trichoduboscqia epeori Léger was found to parasitize nymphs of the mayfly Rhithrogena iridina Kolenati in southwest Germany for a new host record. It was studied by light and electron microscopy. The pansporoblast membrane is evaginated at several points, usually four, to produce long needle-like appendages >20 μm in length with a resilient inner core superficially resembling collagen, which is thought to maintain their orientation. It is suggested that the pansporoblast appendages may play a role in host infection. The structure and ultrastructure of developmental stages are recorded for the first time. Apart from the pansporoblast appendages, the ultrastructure of T. epeori conforms to the general pattern seen in many other pansporoblastic Microspora. Typically 16 spores are produced per pansporoblast but 32-spore pansporoblasts were also found, and the taxonomic significance of this is discussed.     

Electron Microscopical and Biochemical Characterization of Infectious Pancreatic Necrosis Virus

An electron microscopical and biochemical examination of the properties of infectious pancreatic necrosis virus (IPN) and of its ribonucleic acid (RNA) was made. The buoyant density of IPN in CsCl was found to be 1.33 g/cm³. Electron microscopical examination of the banded virus revealed structures similar in size (74 nm) and shape to reoviruses but lacking a characteristic inner capsid structure. Polyacrylamide gel electrophoretic analysis of IPN-RNA revealed a single non-segmented component of molecular weight 3.2 × 10⁶. Its susceptibility to ribonuclease, base composition, and resistance to thermal denaturation indicated a single-stranded RNA structure. However, its sedimentation behavior (16S) independent of ionic strength in sucrose gradients, partial solubility in 2 m LiCl, and ribonuclease resistance in the presence of Mg²⁺ suggest an unusual secondary structure of unknown nature. The accumulated data indicate that IPN virus does not belong to either the picornavirus or reovirus groups and may represent a new group of viruses.     

Further Electron Microscopical Studies of Induced Resistance of Barley against Erysiphe graminis f. sp. hordei

Barley leaves were treated with a resistance inducer and inoculated with Erysiphe graminis two days later. 68 hours after inoculation many infection sites with cytoplasmic aggregations with increased number of golgi apparatus and increased endoplasmic reticulum could be observed. The extrahaustorial membrane invaginated and some free pieces of membrane appeared in the matrix. The haustoria vacuolized partially and curly filamentous electron dense material occurred. These changes took place after protective as well as after curative treatment. Due to cytochemical studies the vacuolar electron dense material in the vacuoles of the haustoria contained polymers of mannose or glucose.     

Light and Electron Microscopic Studies of Microorganisms Growing in Rotating Biological Contactor Biofilms

The biofilms growing in the first compartments of two rotating biological contactors used to treat municipal wastewater were examined by light and electron microscopy. The biofilms were found to contain a complex and varied microbial community that included filamentous and unicellular bacteria, protozoa, metazoa, and (possibly) bacteriophage. The predominant microorganism among these appeared to be a filamentous bacterium that was identical to Sphaerotilus in both morphological and ultrastructural characteristics. It was possible to isolate a Sphaerotilus-like bacterium from each contactor. Both the Sphaerotilus filaments and the wide variety of unicellular bacteria present tended to contain poly-β-hydroxybutyrate inclusions, a probable indication that these organisms were removing carbon from the wastewater and storing it. The microbial population of the biofilms appeared to be metabolically active, as evidenced by the presence of microcolonies and dividing cells.     

OXIDATIVE AND HYDROLYTIC ENZYMES IN THE NEPHRON OF NECTURUS MACULOSUS : Histochemical, Biochemical, and Electron Microscopical Studies

The distribution of oxidative and hydrolytic enzyme activities along the nephron of Necturus maculosus Rafinesque was studied histochemically. The proximal tubule possessed all the demonstrable enzyme activities associated with the hexose-monophosphate shunt and glycolysis, but lacked detectable succinic dehydrogenase and cytochrome oxidase activities. Krebs cycle enzymes other than succinic dehydrogenase were easily detectable. The distal tubule, on the other hand, possessed no detectable hexose-monophosphate shunt enzyme activities, but all demonstrable glycolytic and Krebs cycle enzymes and cytochrome oxidase were present in high activity. These data indicate that the proximal tubule of Necturus probably cannot depend, as can the distal tubule, on the Krebs cycle and cytochrome system to provide energy for its transport processes, an inference supported, in general, by available physiological evidence. The question of the importance of the hexose shunt to proximal tubular function arises. Evidence is presented that the proximal tubular blood supply is primarily venous in nature, a hypothesis which would correlate well with its anaerobic metabolic pattern. In addition, the absence of cytochrome oxidase and succinic dehydrogenase from the proximal tubular cells implies either that they possess very few mitochondria, or that their mitochondria have a very unusual enzymatic pattern. Electron microscopical observations and data obtained from the measurement of the enzyme activities of homogenates of Necturus kidney are presented which indicate that the second hypothesis is more probably correct.