Raillietina melomyos n. sp. (Cestoda,Davaineidae) from mosaic-tailed rats in Papua New Guinea

Raillietina melomyos n. sp. from the small intestine ofMelomys rufescens in the Western Highlands of Papua New Guinea differs from related species in combinations of the number (170–190) and length (8–11 m) of the rostellar hooks, the number of testes (21–36) and of egg capsules per gravid proglottid (56–92), and in that the cirrus-sac does not reach the longitudinal osmoregulatory canals.     

Cysticercoids of five species of Raillietina Fuhrmann, 1920 (Cestoda: Davaineidae) in ants,Pheidole sp., from emu farms in Australia

Cysticercoids of five species of Raillietina, R. australis (Krabbe, 1869) Fuhrmann, 1924, R. beveridgei O'Callaghan, Davies & Andrews, 2000, R. chiltoni O'Callaghan, Davies & Andrews, 2000, R. dromaius O'Callaghan, Davies & Andrews, 2000 and R. mitchelli O'Callaghan, Davies & Andrews, 2000, parasitic in the emu Dromaius novaehollandiae Latham, are described. Each species was identified on the basis of the number and size of the rostellar hooks, which correspond to those of adult worms. Cysticercoids were recovered from the haemocoele of the gaster of ants belonging to the genus Pheidole (Hymenoptera: Formicidae) in Australia. There was a trend towards an inverse relationship between the size of the cysticercoids and the parasite burden in the intermediate host.     

Histochemical studies on the distribution of thiamine pyrophosphatase and enzymes related to carbohydrate metabolism in the intercalated neurons of the rat supraoptic nucleus

Histochemical studies have been conducted by applying hexokinase (HK), aldolase (AD), glyceraldehyde-3-phosphate dehydrogenase (G3), succinate dehydrogenase (SDH), glucose-6-phosphate dehydrogenase (G6PD), and thiamine pyrophosphatase (TPPase) methods, as well as Nissl staining and Gomori's chrome-alum-hematoxylin-phloxine (CHP) methods to intercalated neurons of the supraoptic nucleus (SO) on Wistar strain rats. Intercalated neurons reacted weakly to the AD, G3, G6PD, and SDH tests, indicating that they belong to the category of ordinary neurons with low carbohydrate metabolism. Many fibrous astrocytes showing strong HK reactions surround neurosecretory neurons. However, they do not surround intercalated neurons with mild HK activity. These results indicate that the latter receive a poor supply of energy from glucose in the circulating blood in contrast to the former. Intercalated neurons are very rich in Nissl substance but lack CHP-positive material. They may have a high potential for synthesizing protein. The principal morphological features of the TPPase-positive Golgi material are peculiar and heterogeneous shape and poor development. These findings together with mild G6PD activity suggest that intercalated neurons are very likely to have poor synthesizing activity.     

Histochemical studies on the morphology of the Golgi apparatus in the neurons of supraoptic and paraventricular nuclei of the normal and dehydrated rabbit (application of the thiamine pyrophosphatase method)

Summary Detailed histochemical studies have been conducted on the morphology of the Golgi apparatus by applying the thiamine pyrophosphatase technique (Novikoff and Goldfisher, 1961) to the neurons of supraoptic and paraventricular nuclei of normal and dehydrated rabbits. The neurons in both nuclei were classified into five categories on the basis of the morphology of the Golgi apparatus. The number of cells in individual categories were counted to evaluate the percentage of each category in the whole nucleus.Neurons have many vesicles which show the tendency to form clusters. Such clusters are present also in the basal bodies. The Golgi apparatus is localized near one side of the nucleus in many neurons. The neurons indicate phasic activity of resting, anabolic and catabolic stages under normal conditions.During dehydration, the Golgi apparatus went through the three stages of network formation, the increase of the budding-off process and later on disintegration. The supraoptic nucleus reacted to the TPPase test more severely than the paraventricular nucleus, whereas the former went through the stages more slowly than the latter. The paraventricular nucleus also revealed sensitivity to osmotic stress.     

Poly(L-lysyl-L-alanyl-alpha-L-glutamic acid). II. Conformational studies.

The solution characterization of poly(Lys-Ala-Glu) is described. This polytripeptide is zwitterionic at neutral pH and is shown to take on a conformation which is dictated by the state of ionization, molecular weight, temperature, and solvent. The polypeptide is almost entirely α-helical at low pH and temperature for polymers of greater than 25,000 molecular weight. Melting profiles for these conditions show t_m ～ 20°C. Analysis of circular dichroism curves shows the α-helical content to vary in a linear manner with molecular weight in the range 3000–30,000. At neutral pH the charged polypeptide is essentially random, but substantial α-helix could be induced by addition of methanol or trifluoroethanol. At temperatures where the sequential polypeptide is a random coil, addition of trifluoroethanol produces a polymer which is mostly α-helical but also contains an appreciable ammount of β-structure. The infrared spectrum of a low-molecular-weight fraction assumed to be cyclo(Lys-Ala-Glu)₂ was tentatively assigned a β-pleated sheet structure. A comparison of this polytripeptide in various ionization states with other polytripeptides containing L -alanine and L -glutamate or L -lysine shows the α-helix directing properties for the (uncharged) residues to lie in the order Ala > Glu > Lys.     

Histochemical localization of phosphomonoesterases in Avitellina lahorea Woodland, 1927 (Cestoda: Anoplocephalida)

Non-specific and specific phosphatases have been histochemically localized in the tissues of Avitellina lahorea, an intestinal parasite of sheep and goats. Large quantities of acid phosphatase, alkaline phosphatase and adenosine triphosphatase were observed in almost all organs except the parenchyma where there were moderate amounts of acid phosphatase and no alkaline phosphatase; the reproductive ducts contained moderate amounts of alkaline phosphatase. 5-nucleotidase was observed only in the uterus, egg pouches and eggs and glucose-6-phosphatase activity was restricted to the tegument. The probable functions of these moieties at different sites are discussed.     

Histochemical and ultrastructural studies on the metacercarial cyst of Echinostoma revolutum (Trematoda).

Histochemical and ultrastructural studies were made on the metacercarial cyst of Echinostoma revolutum obtained from the kidney of experimentally infected Physa and Lymnaea snails. Ultrastructural studies revealed three cyst walls, an outer, middle and inner. The outer wall was more electron-dense than the middle, and contained coarser granules than those found in the middle layer. The inner wall was lamellated and contained membranous whorls. Collagenous fibers presumably of host origin surrounded the outer cyst wall. The outer and middle cyst walls stained identically with all histochemical procedures used. These walls contained acid mucopolysaccharides and glycoprotein, whereas the inner cyst wall contained glycoprotein. All cyst walls stained positively with a variety of protein stains.     

Ultrastructural studies on the reproductive system of Gyrocotylidea and Amphilinidea (Cestoda)

Summary The vitellaria, vitellocyte development and vitelloduct of Gyrocotyle urna are described at the ultrastructural level. Vitellar follicles are surrounded by an extracellular lamina; vitellocytes and the periphery of the follicles are enclosed by a cytoplasmic sheath. Immature vitellocytes are spherical and show a high nucleus-to-plasma ratio. During maturation of vitellocytes their cytoplasmic content increases and numerous dictyosomes, endoplasmic reticulum, egg-shell granules and lipid droplets are formed. Lipid droplets and egg-shell granules fill most of the volume of mature vitellocytes. The vitelloduct is ciliated and shows intraepithelial nuclei and intraluminal folds. No cell borders have been found within the vitelloduct. Vitellogenesis and the vitelloduct morphology of Gyrocotyle are compared with those of other parasitic Plathelminthes.Abbreviations I immature vitellocyte - II maturing vitellocyte - III mature vitellocyte - Az cytoplasmic sheath surrounding the vitellocytes and the follicle - bb basal body - ci cilia of the vitelloduct - ld lipid droplet - mi mitochondrium - nu nucleus - rer rough endoplasmic reticulum - sg egg-shell granulum - ve vesicles     

Peptidases II. Localization of dipeptidylpeptidase IV (DPP IV). Histochemical and biochemical study]

Fresh frozen, unfixed, chloroforme-acetone treated or freeze-dried cryostat sections or sections from aldehyde-fixed blocks of tissue were tried for the histochemical investigation of dipeptidylpeptidase IV (DPP IV) with L-glycyl-L-prolyl(gly-pro)-naphthylamides as substrates and stable or unstable diazonium salts for simultaneous coupling and various buffers, pH 5--7.5 in rats, mice, guinea-pigs, cats, rabbits, hamsters and human enterobiopsies. The best results are obtained with 1.7--3.4 mM gly-pro-4-methoxy-2-naphthylamide and 1 mg Fast Blue B/ml or (with some limitations) 0.025 ml hexazotized new fuchsine/ml in 0.1 M cacodylate or phosphate buffer, pH 7.5 and unfixed sections for the demonstration of the total activity of DPP IV and freeze-dried celloidin-mounted cryostat sections for the precise localization of the enzyme or the detection of lysosomes, Golgi apparatus and secretion granules sections from aldehyde fixed tissue blocks are only suitable to study the lysosomal hydrolysis of gly-pro-naphthylamides between pH 5 and 7 when hexazotized p-rosaniline or new fuchsine are employed. DPP IV is firmly bound to strutures and shows species- and organ-dependent differences. In general, the enzyme occurs in the capillary endothelium, sinusoidal cells, perineurium, epithelial cells of intercalated and striated ducts, microvillous zone of intestinal crypts and villi, uterus, Fallopian tubes, ductus epididymis and proximal renal tubules, hepatocyte and lymphocyte membrane, plasmalemma of pseudostratified and transient epithelia and in the capsules and interstitium of many organs. These sites of activity can be completely inhibited by diisopropyl fluorophosphate and partially by Pb2+; Mg2+, Mn2+, Co2+ EDTA are without any influence. Phenantrolin may activate DPP IV. The biochemical assay works with 10 mM gly-pro-2-naphthylamide in 0.1 M cacodylate buffer, pH 7; the enzyme activity is determined fluorometrically in guinea-pig and rat organs; the data confirm and enlarge the species- and organ-dependent differences revealed by histochemistry. Compared with other dipeptide as well as tripeptide and amino acid naphthylamides the results obtained for DPP IV suggest a peptidylpeptidase which seems to be involved in other metabolic processes beside the degradation of collagen.     

Dipicolinato complexes of cobalt(II), copper(II) and zinc(II) with thiamine dications

Cobalt(II), copper(II) and zinc(II) dipicolinato complexes having thiamine dication with compositions [HT][CoL₂]·5H₂O (1), [HT][CuL₂]·5H₂O (2) and [HT][ZnL₂]·5H₂O (3) (L = dipicolinato anion, T = thiamine cation) are synthesized, characterized by X-ray diffraction and other spectroscopic techniques. The thiamine part in these complexes exists as divalent cations. The second protonation of thiamine takes place at the less crowded nitrogen atom of the pyrimidine ring. These complexes are stabilized by electrostatic and hydrogen-bonding interactions of -N⁺-H and -COO⁻ groups along with crystallized water molecules. The complexes are stable in solution as determined by ¹H NMR and visible study. The complex 1 has two medicinal components which can be easily separated by controlling pH in aqueous medium. It gets decomposed on treatment with sodium hydroxide at pH > 8 to form neutral complex {[Na₂(μ-H₂O)₃(H₂O)₃][CoL₂]·H₂O}₂.     

Histochemical studies on the amphibian opercularis muscle (Amphibia)

Summary Histochemical studies of the opercularis muscle of the bullfrog (Rana catesbeiana) and the tiger salamander (Ambystoma tigrinum) provide evidence that the opercularis muscle of anurans is a specialized, tonic portion of the levator scapulae superior muscle. Staining results for myosin adenosine triphosphatase (ATPase) and succinate dehydrogenase (SDH), combined with measurements of muscle fiber diameters, demonstrate that the opercularis/levator scapulae superior muscle mass of both the tiger salamander and bullfrog consists of an anterior tonic portion, a middle fast oxidative-glycolytic (FOG) twitch portion, and a posterior fast-glycolytic (FG) twitch portion. In R. catesbeiana the tonic fibers represent 57.3% of the fiber total and (because they have relatively narrow diameters) about 29% of the cross-sectional area of the muscle mass, and form that part of the muscle (=opercularis muscle) that inserts on the operculum. In Ambystoma the tonic fibers represent only 8.8% of the fiber total and represent about 4% of the cross-sectional area. In the tiger salamander, the entire levator scapulae superior muscle inserts on the operculum and therefore represents the opercularis muscle. The bullfrog differs from the tiger salamander, therefore, in that the anterior tonic part of the opercularis/levator scapulae superior complex is greatly enlarged and the insertion on the operculum is limited to these tonic fibers. No evidence of a columellar muscle was found in R. catesbeiana. Previous reports of one in this species and in other anurans may be based on the tripartite nature of the opercularis/levator scapulae superior muscle mass. The middle FOG portion of the muscle may have been considered a muscle distinct from the anterior tonic portion (=opercularis muscle) and the posterior FG portion.     

Histochemical studies on eggshell formation in Paramphistomum cervi (Digenea: Paramphistomatidae)

The formation of the egg mass in the ootype, containing the oocyte, vitelline cells, numerous spermatozoa and Mehlis' gland secretion marks the beginning of eggshell formation. Mehlis' gland cells pour their lipoprotein secretion into the ootype; this secretion forms a thin template around the egg mass and upon this template the shell globules are deposited. Eggshell formation begins in the proximal uterus and is completed in the middle uterus. The eggshells are devoid of phenols and phenolase indicating that hardening is not by quinone tanning. The eggshells contain keratin and are stabilized by disulphide linkages.