Histochemical studies of dopa oxidase and peroxidase in the mantle-edge of the freshwater gastropod, Helisoma duryi eudiscus (Pilsbry)

1968 ◽  
Vol 46 (2) ◽  
pp. 165-167 ◽  
Author(s):  
S. P. Kapur ◽  
M. A. Gibson
Keyword(s):  
Positive Reaction ◽  
Protein Component ◽  
Negative Reaction ◽  
Structural Proteins ◽  
Freshwater Gastropod ◽  
Helisoma Duryi ◽  
Mantle Edge ◽  
Dopa Oxidase ◽  
Oxidase Reaction

The mantle-edge gland produces the highly tanned, densely fibrous periostracum, and the cubocolumnar cells contribute to the deposition of the less highly tanned matrix of the inner shell layers. The mantle-edge gland gives positive reactions for dopa oxidase and peroxidase, but does not contain melanin. The cubocolumnar cells reveal a positive reaction for dopa oxidase, possess numerous melanin granules, and exhibit a negative reaction for peroxidase. It is suggested that quinones may contribute to the process of tanning and hardening of the structural proteins of the shell. The dopa oxidase reaction within the cubocolumnar cells indicates the presence of tyrosine and suggests that these cells are capable of producing quinones to color and harden the protein component of the inner shell layers. It also explains the abundance of melanin granules within these cells. Within the mantle-edge gland, it is suggested that the peroxidase inhibits the formation of melanin from dopa quinone, and peroxidase, by accentuating quinone production, may cause further hardening of the periostracum.

A histochemical study of the development of the mantle-edge and shell in the freshwater gastropod, Helisoma duryi eudiscus (Pilsbry)

1968 ◽  
Vol 46 (3) ◽  
pp. 481-491 ◽  
Author(s):  
S. P. Kapur ◽  
M. A. Gibson
Keyword(s):  
Alkaline Phosphatase ◽  
Ribonucleic Acid ◽  
Ground Substance ◽  
Freshwater Gastropod ◽  
Helisoma Duryi ◽  
Yellow Body ◽  
Golgi Element ◽  
Mantle Edge ◽  
Extrapallial Fluid ◽  
Distal Border

Glycogen and ribonucleic acid are present in the mantle-edge during the prehatching period and in the adult. The cubocolumnar epithelium contains the largest stores of glycogen. Ribonucleic acid is most abundant in the mantle-edge gland, and the mucous and mucoprotein cells. Mucopolysaccharides and glycoproteins occur within the mantle-edge epithelium, excepting the mantle-edge gland, and within the shell ground substance. Mucous glands and the sheath surrounding the organic plates are rich in sulfated mucopolysaccharides. Alkaline phosphatase and calcium could not be demonstrated during the prehatching stages. In the adult, alkaline phosphatase reactions are intense along the distal border of the cubocolumnar epithelium, and the basal borders of the epithelia of the mantle-edge gland, median lobe, and ventral lobe. Calcium carbonate occurs as spherules in the connective tissue, in the extrapallial fluid, and within the organic plates and crystalline layers of the shell. In the adult, lipids are most plentiful in the dorsal lobe epithelium and yellow body cells. Vitamin A occurs only within the cubocolumnar and yellow body cells. Cytochrome oxidase is present within the mantle-edge epithelium and, in terms of relative amounts, reflects the activity of the various lobes. Similarly, the size of the Golgi element can be correlated with the activity of the mantle-edge epithelia.

A HISTOLOGICAL STUDY OF THE DEVELOPMENT OF THE MANTLE-EDGE AND SHELL IN THE FRESHWATER GASTROPOD, HELISOMA DURYI EUDISCUS (PILSBRY)

1967 ◽  
Vol 45 (6) ◽  
pp. 1169-1181 ◽  
Author(s):  
S. P. Kapur ◽  
M. A. Gibson
Keyword(s):  
Histological Study ◽  
Ground Substance ◽  
Dorsal Lobe ◽  
Crystalline Layer ◽  
Tissue Core ◽  
Freshwater Gastropod ◽  
Helisoma Duryi ◽  
Yellow Body ◽  
Mantle Edge ◽  
Calcium Crystals

The mantle-edge originates as a peripheral thickening of the evaginated shell gland. During the prehatching stages, it differentiates to form a dorsal lobe including the mantle-edge gland, a median lobe, and a ventral lobe possessing numerous mucous glands. The connective tissue core contains yellow body cells, amoebocytes, and mucoprotein glands. The protoconch is composed of fibers embedded in an amorphous ground substance. Initially it is secreted by the entire mantle-edge but, as development advances, its secretion is progressively limited to the mantle-edge gland. The adult shell is composed of the periostracum, crystalline layer, and an inner layer. The periostracum is a highly tanned layer of fibers embedded in a ground substance. The crystalline layer consists of calcium crystals, the smaller of which contain a nucleus. The inner layer is composed of organic plates which possess amoebocyte nuclei, yellow bodies and calcium granules, and which are surrounded by a thick envelope containing sulfated mucopolysaccharides. These calcium crystals and organic plates are embedded in a ground substance. It is believed that the mantle-edge gland produces the periostracum, that the dorsal lobe contributes to the inner two shell layers, and that the mucous and mucoprotein glands, yellow body cells, and amoebocytes play a significant role in the deposition and calcification of the shell.

The New Edition of the Guide to Clinical Preventive Services

PEDIATRICS ◽  
1996 ◽  
Vol 97 (5) ◽  
pp. 733-735
Author(s):  
Modena Wilson ◽  
Donald M. Berwick ◽  
Carolyn DiGuiseppi
Keyword(s):  
Primary Care ◽  
Positive Reaction ◽  
Task Force ◽  
Preventive Services ◽  
Negative Reaction ◽  
The Past ◽  
The Us ◽  
Clinical Preventive Services ◽  
Clinical Prevention ◽  
And Training

Preventive services compose a large portion of primary care pediatrics, and pediatricians by their nature and training seem extraordinarily disposed toward clinical prevention. Therefore, when the first edition of the Guide to Clinical Preventive Services appeared in 1989 from the US Preventive Services Task Force (USPSTF), the negative reaction of the organized pediatric community was disappointing. The second edition of that guide has just been released, and we three pediatricians, who have worked hard during the past 5 years as members and staff of the second task force, hope for a far more positive reaction from our colleagues this time around.

A histochemical study of calcium storage in the foot of the freshwater gastropod, Helisoma duryi eudiscus (Pilsbry)

1968 ◽  
Vol 46 (5) ◽  
pp. 987-990 ◽  
Author(s):  
S. P. Kapur ◽  
M. A. Gibson
Keyword(s):  
Alkaline Phosphatase ◽  
Staining Intensity ◽  
Histochemical Demonstration ◽  
Staining Reaction ◽  
Connective Tissues ◽  
Intense Staining ◽  
Freshwater Gastropod ◽  
Helisoma Duryi ◽  
The Matrix ◽  
And Storage

Shortly after hatching, calcium appears in the form of numerous spherules within the connective tissue of the foot of Helisoma. Concomitantly, there is a change in the histochemical demonstration of sulfated mucopolysaccharides, glycogen, and alkaline phosphatase. The sulfated mucopolysaccharide component of the mucous glands and the mucous coating of the foot increase in staining intensity. Similarly, the glycogen content of the foot epithelium and subepithelial connective tissues increases in staining intensity. Also, alkaline phosphatase first appears and exhibits an intense staining reaction within the foot epithelium. It is suggested that the coincidental appearance of these substances is related to the percutaneous absorption and storage of calcium. It is proposed that the sulfated mucopolysaccharides absorb calcium from the environment, that this calcium–mucous complex is hydrolyzed by the alkaline phosphatase, that the released calcium becomes bound to the fibers and sulfated mucopolysaccharides forming the matrix of the spherules, and that the calcium is accumulated in the form of such spherules.

scholarly journals Isolation of natural inhibitors of papain obtained from Carica papaya latex

2004 ◽  
Vol 47 (5) ◽  
pp. 747-754 ◽  
Author(s):  
Rubens Monti ◽  
Jonas Contiero ◽  
Antonio José Goulart
Keyword(s):  
Positive Reaction ◽  
Carica Papaya ◽  
Competitive Inhibition ◽  
Gel Filtration ◽  
Exchange Chromatography ◽  
Negative Reaction ◽  
Ionic Exchange ◽  
Papaya Latex ◽  
Carica Papaya Latex ◽  
Natural Inhibitors

Studies were carried out to natural papain inhibitor from papaya latex. Fresh latex from green fruits of Carica papaya was collected and immediately transported in ice bath to the lab, from which three fractions with inhibitor effect of esterase papain activity were isolated by latex dialysis, Sephadex G-25 gel filtration and ionic exchange chromatography in SP-Sephadex C-25. The isolated fractions, identified as inhibitors I and II, showed a negative reaction with ninhydrin; however, the fraction identified as P-III showed positive reaction with ninhydrin. Kinetics data showed non-competitive inhibition (inhibitor I) and uncompetitive (inhibitors II and P-III).

Polysaccharides in the different stages of the life-cycles of certain sporozoa

Parasitology ◽  
1960 ◽  
Vol 50 (3-4) ◽  
pp. 509-514 ◽  
Author(s):  
B. Dasgupta
Keyword(s):  
Positive Reaction ◽  
Life Cycles ◽  
Negative Reaction ◽  
Malaria Parasites ◽  
Residual Mass ◽  
Strong Positive Reaction ◽  
Residual Masses

Glycogen proved to be absent in the malaria parasites (Plasmodium and Hepatocystis) by applying cytochemical methods; while in the piroplasms (Theileria and Babesia), and in Hepatozoon glycogen could be demonstrated by using the same methods. A strong positive reaction for polysaccharides was obtained in the residual masses of Hepatozoon sciuri, and H. balfouri; while a negative reaction was obtained in the residual mass of Plasmodium. A positive reaction for polysaccharides was obtained in the following structures: the wall of the oocysts of Plasmodium, the gametocyte capsules of Hepatozoon sciuri and Hepatozoon sp., the sporoblast capsule of H. sciuri, and the polar areas of the gametocyte of H. balfouri.

scholarly journals To the treatment and cure of gonorrhea

2021 ◽  
Vol 25 (11) ◽  
pp. 1238-1238
Author(s):  
A. Dmitriev
Keyword(s):  
Mucous Membrane ◽  
Positive Reaction ◽  
Microscopic Examination ◽  
Negative Reaction ◽  
Years Of Experience ◽  
Protein Therapy ◽  
Hot Baths

Schollz (D. m. W. No. 31, 29), on the basis of his many years of experience in the treatment of gonorrhea, indicates that Protargol and Albargin remain the best drugs to this day, because they act not only in a killing manner on gonococci, but also exert their influence on mucous membrane in the sense of its impregnation. In cases where gonococci sit deep in tissues (prostata, epididymis, ovaries), the author recommends using protein therapy. In stubborn cases, it is recommended to "Fieberbehandlung" with hot baths or inoculation with malaria. To establish the fact that gonorrhea has been cured, the author uses microscopic examination after a series of provocations, and also examines the patient with the help of cultures. An excellent means for establishing the cure of gonorrhea is the B.-G. reaction, and a negative reaction that occurred after the previous positive one is more likely to speak for a cure, while a persistent positive reaction indicates the need for a series of repeated microscopic and bacteriological studies.

The Occurrence of Mucoid Substances in Insects

1949 ◽  
Vol 2 (4) ◽  
pp. 421 ◽  
Author(s):  
MF Day
Keyword(s):  
Salivary Glands ◽  
Positive Reaction ◽  
Goblet Cells ◽  
Negative Reaction ◽  
Peritrophic Membrane ◽  
Insect Midgut ◽  
Larval Midgut ◽  
Animal Phyla ◽  
Rectal Glands ◽  
Histochemical Tests

Three histochemical tests, which demonstrate mucoid substances of vertebrate origin, have been applied to a variety of insect tissues. Mucoid materials seem to be absent from the contents of the insect midgut, but a positive reaction may be given by. the striated border of the epithelium. Goblet cells of the larval midgut of Lepidoptera and rectal glands of all of the insects studied give a negative reaction, but the salivary glands of the cockroach, grasshopper, larval calliphorids, and worker honeybee all contain mucoid substances. In general, these materials seem to be of less frequent occurrence in insects than they are in most other animal phyla. The significance of the observed distribution of mucoid substances in insects is discussed, particularly in relation to the functions of the peritrophic membrane and the salivary glands.

scholarly journals Political Quotas in India

Asian Survey ◽  
2012 ◽  
Vol 52 (2) ◽  
pp. 373-394 ◽  
Author(s):  
Francesca Refsum Jensenius
Keyword(s):  
Positive Reaction ◽  
National Election ◽  
Negative Reaction ◽  
Election Study ◽  
National Election Study ◽  
Strong Positive Reaction ◽  
Scheduled Castes

Abstract India has had political quotas for Scheduled Castes (SCs) since 1950. Using the 2004 National Election Study, this paper finds that neither SCs nor non-SCs feel that their vote is more/less efficacious living in SC constituencies. Yet, some evidence is found in this study that SCs are approached for their vote more often in SC constituencies. Overall, this suggests that quotas are neither associated with a strong positive reaction among SC voters nor a strong negative reaction among non-SC voters.

Sign in / Sign up

Export Citation Format

Share Document