Inflammatory reaction of rat striated muscle to particles of carbon fiber reinforced carbon.

1. Carbon fiber reinforced carbon (CFRC) was implanted in rats as particles measuring 30 microns or 11 microns, denoted as CFRC-A and CFRC-B, respectively. Titanium (Ti) and vitreous carbon (VC) were used as controls.

The blood circulation inside the spleen. I. The arterial blood vessels general distribution in the rat spleen.

As an attempt to investigate the different pathways followed by the blood into the spleen and to analyse their functional significance, a technique was used mainly based on the intraarterial perfusion of a Prussian blue "solution" added of some chemical mediators and vasoactive substances. Such technique provides results which may be analysed taking into account the effect of the anaesthetic used, that may influence the findings. From the anaesthetic used, the sulfuric ether and the barbital sodium produce vasoconstriction of the white pulp blood vessels, whereas the chlorpromazine-promethazine doesn't have this effect, and so the Prussian blue appears inside these vessels.

The argentophil reticular cells of the mammalian spleen. II. The argentophil reticular cell arrangement inside the red pulp and its relationship with the endothelial lining cells of the splenic sinuses.

The red pulp's argentophil reticular cell network of the spleen is composed by 3 types of fixed cells: 1. the primitive reticular cell, slightly argentophil; 2. the small reticular cell; 3.

The mechanism accounted for the silver staining "fast techniques" development and its histochemical meaning. II. The binding between silver and ferric ion accounted for the silver staining development.

Results obtained on filter paper strips models show that some protein and fatty acids become argentophil as an effect of a previously binding ferric ion although, in this instance, the silver staining can only be accomplished by using a silver diamine solution, since a silver nitrate solution is not effective. However, if the filter paper model is previously treated by a "multidentate ligand" before the silver nitrate solution treatment becomes able in doing the silver staining. This result shows that the binding between Fe3+ and Ag+ can be done if a suitable negatively charged "multidentate ligand" has been connected between them.

The mechanism accounted for the silver staining "fast technique" development and its histochemical meaning: I. The correlation between the silver staining intensity and the tissue bound ferric ion and some other tissue histochemical reactivities.

The mechanism accounted to accomplish the silver staining "fast technique" on tissues sections was studied towards the correlation among histophotometric measures concerning the silver staining intensity and the intensity provided by some histochemical reactions performed on spleen and liver sections from rats and pigs. By treating previously these histological sections with thioglycolate or oxalate solutions in progressive concentrations and afterwards subjecting them to a silver staining "fast technique", it was demonstrated that the silver staining intensity decreases proportionally to the thioglycolate or the oxalate solution concentration. The regression line of the silver staining intensity on the thioglycolate or the oxalate solution concentration was established, as well as its regression coefficient.

A histochemical study on the vitamin D synthesis into the epidermis.

Using a suitable histochemical method vitamins D and 7-dehydrocholesterol could be shown into the epidermis of several mammal species. As the histochemical method used is able to discriminate vitamins D and 7-dehydrocholesterol from cholesterol and its esters, the sites where these vitamins were synthesized within the epidermis layers could be established. Vitamins D and 7-dehydrocholesterol were found into the epidermis in the same sites where cholesterol and its esters take place, such as: the keratinizing cell thick membrane and the stratum spinosum and stratum granulosum keratinocytes cytoplasm.

A histochemical investigation on the percutaneous absorption of vitamin D synthesized into the mammal epidermis.

The vitamin D transepidermis absorption was studied by means of a histochemical technique suitable to detect this vitamin and to discriminate it from cholesterol and its esters. Such technique shows vitamin D inside the mast cell granules. As the mast cell granules contain metachromatic substances its own histochemical reactivity must be previously blocked by methylation.

A histochemical method able to detect vitamins D and to discriminate it from cholesterol and its esters.

A suitable histochemical method able to discriminate vitamins D and 7-dehydrocholesterol from cholesterol and its esters is proposed taking into account the alkaline permanganate-toluidine blue reaction, the alkaline permanganate-Schiff reaction and the inhibitory effect of the HgCl2-formalin fixative. This method appears specific according to the results provided by spot test. On tissue sections the alkaline permanganate-toluidine blue reaction is more sensitive and more specific than the alkaline permanganate-Schiff reaction.

Histochemical aspects concerning the synthesis and the fate of cholesterol into the epidermis.

By means of a suitable histochemical method free cholesterol and its esters could be detected into the epidermis layers. The results show that in the stratum spinosum keratinocytes free cholesterol appears as an amorphous or granular structure apparently protein unbound; into the stratum granulosum keratinocytes the cholesterol becomes protein-bound and its most part undergoes esterified. The extracellular compartment nearly the stratum granulosum contains a little amount of cholesterol esters loosely bound to proteins.

A histochemical method suitable to discriminate free cholesterol from its esters and both from 7-dehydrocholesterol and vitamins D.

The peracetic acid-toluidine blue and the peracetic acid-Schiff reactions as well as the failure of HgCl2-formalin fixative for inhibiting these reactions appears as a very useful method for free cholesterol histochemical detection and to discriminate it from its esters and from some of its metabolic products such as 7-dehydrocholesterol and vitamins D. The cholesterol histochemical detection provided by those reactions appears specific taking into account the findings afforded by spot tests. The peracetic acid-toluidine blue reaction is very suitable for histochemical purposes on tissue sections, since it does not produces tissues damages, it is sensitive and the stained end product is almost insoluble in the solvents frequently used in histological techniques.

Identification of tocopherol (vitamin E) in the skin and its histochemical detection.

The epidermis upper layer reacts positively to the performic acid-toluidine blue and the performic acid-Schiff; such reactions were inhibited by a previous formalin-HgCl2 fixation. The substance accounted for that reactivity could be extracted from skin histological sections by means of the chloroform-methanol-HCl effect. If this same solvent was used on human skin shaven horny layer powder it was able to extract protein-lipid complex that displays the tocopherol histochemical reactivity.

A technique to tocopherol (vitamin E) histochemical detection.

A technique to detect tocopherol histochemically was proposed in basis on the following schedule: 1. toluidine blue and Schiff reagent negativity before a suitable oxidation; 2. performic acid-toluidine blue and performic acid-Schiff reagent positivity after fixing in formalin-CaCl2; 3.

The spleen-hypophysis relationship - the effect of splenectomy on the young rat growth.

The spleen-hypophysis relationship particularly the effect of splenectomy on the body growth rate was studied on young rats from both sexes. The following experimental groups were tested: 1. sham-operated controls; 2.

An analysis on the specificity of the histochemical techniques already proposed to detect catalases and peroxidases.

The spot test carried on filter paper strips appears as a very suitable technique to investigate the reactivity of catalases, peroxidases, porphyrins (bilirubin and protoporphyrin), metalloporphyrins (haemoglobin, haemin, haematin, chlorophyll and cyanocobalamin), ferric and ferrous salts. By using this technique the specificity of the already proposed techniques admitted as appropriate to detect histochemically peroxidases and catalases was investigated. The results shown from the already proposed techniques to detect peroxidases only the alpha-naphthol reaction is somewhat specific for this enzyme, if the results were taken immediately.

Histochemical technique to detect choline-containing lipids.

An almost specific and highly sensitive technique to detect histochemically choline-containing lipids is proposed. This technique is based on the effect of Hg++ and phosphomolybdic ion on the choline, that yields insoluble complexes able to react with diphenylcarbazide producing a deep blue or violet stain. The specificity and the sensitivity of this technique was investigated on filter paper strips loaded with choline-containing lipids, choline-free lipids, steroids, vitamins, proteins or choline hydrochloride.

Catalases and peroxidases histochemical detection; techniques suitable to discriminate these enzymes.

By using the benzidine reaction, on filter paper strips loaded with catalases, peroxidases, porphyrins, haemic iron compounds and iron salts, it was possible to establish 2 histochemical techniques able to detect and discriminate catalases and peroxidases. Spot test analytical studies show that only peroxidases oxidize benzidine in presence of a 0.0015 M H2O2 final concentration into the incubation medium.

Immunochemical specificity of a benzidine technique proposed to catalases histochemical detection.

As an attempt to test the specificity of an histochemical technique proposed to detect catalases, an investigation was carried out by immunochemical techniques. Purified catalases were used after analysed immunochemically by double immune diffusion test and immunoelectrophoretic technique. These pure catalases induced, after injecting into guinea-pigs, anti-serums that react specifically with catalase and does not give any cross reaction with peroxidases and haemic iron containing compounds.

The benzidine technique for histochemical detection of the SO4 ion.

The benzidine technique for histochemical detection of the SO4 ion was studied analytically on filter paper strips loaded with 0.02 ml of solutions of sulfate containing and sulfate free substances. The influence of the benzidin solution pH on the SO4 and PO4 ion precipitation was analysed and the experimental condition where the SO4 ion was specifically precipitated was established.

Quantitative assay of Schieff and PAS reactivity during nerve degeneration in rats.

Quantative histochemical analysis of nerve degeneration in rats from zero to 192 hours was studied utilizing both Schiff reagent and PAS reaction. In addition, amylase digestion prior to PAS staining and aniline blockade of Schiff reactivity were employed. The staining intensity of all the reaction was measured histophotometrically and the mean optical density (OD) was determined for the following time intervals: 0, 24, 48, 96, and 192 hours.

Histochemistry of the amyloid substance from familial amyloidotic polyneuropathy.

The histochemical properties of the amyloid substance from familial amyloidotic polyneuropathy (FAP) were studied. The results showed differences among the FAP amyloid and the others amyloid substance. The main difference being that FAP amyloid substance was free of or only contain a small amount of protein.

Morphological changes in the lymphoid organs induced by diphenylhydantoin sodium (DPH).

In rats injected with DPH the morphological changes induced in the thymus and lymph nodes were studied. In the thymus, features suggesting block of cellular differentiation were found, and in lymph nodes depletion of the paracortical zone and intense plasma cell hyperplasia could be observed. The correlation of these findings with the functional changes in the immunological response induced by the drug, and the possible implications of these changes in the induction of lymphoma are discussed.