Further studies on human enteric coronaviruses

Summary Comparisons were made between human enteric coronaviruses and the enteric coronaviruses of pigs and calves by negative staining.Examination of human intestinal organ culture fluids at various time intervals after inoculation with the human enteric coronavirus showed increasing numbers of particles in the fluids.Thin sections of the columnar epithelial cells of these explants showed a number of features consistent with the replication of known human and animal coronaviruses. Virus particles found in thin sections had a mean diameter of 68 nm. In addition, a structure was found in thin sections which has not been described previously. This structure may represent the viral nucleocapsid.With 6 Figures     

Further studies on the transverse bands

Summary The paranodes of cerebral white matter of lanthanum-treated rats were studied in thin sections. The transverse bands were found to be oriented both parallel, and at an angle to the spaces between lateral loops.     

Stimulation of granulocytic cell iodination by pine cone antitumor substances

Antitumor substances (Fractions VI and VII) prepared from the NaOH extract of pine cone significantly stimulated the iodination (incorporation of radioactive iodine into an acid-insoluble fraction) of human peripheral blood adherent mononuclear cells, polymorphonuclear cells (PMN), and human promyelocytic leukemic HL-60 cells. In contrast, these fractions did not significantly increase the iodination of nonadherent mononuclear cells, red blood cells, other human leukemic cell lines (U-937, THP-1, K-562), human diploid fibroblast (UT20Lu), or mouse cell lines (L-929, J774.1). Iodination of HL-60 cells, which were induced to differentiate by treatment with either retinoic acid or tumor necrosis factor, were stimulated less than untreated cells. The stimulation of iodination of both PMN and HL-60 cells required the continuous presence of these fractions and was almost completely abolished by the presence of myeloperoxidase inhibitors. The stimulation activity of these fractions was generally higher than that of various other immunopotentiators. Possible mechanisms of extract stimulation of myeloperoxidase-containing cell iodination are discussed.     

Further cytogenetic studies on acute promyelocytic leukemia

Chromosomes were analyzed in nine cases of acute promyelocytic leukemia (APL-M3), including a follow-up case and an erroneously diagnosed case from our previous reports. The reciprocal 15; 17 translocation, t(15q+; 17q?), was found in all cases, and the break points were estimated to be 15q22 or q23 and 17q12. In addition, trisomy 8 and an isochromosome of the long arm of the affected chromosome #17, i(17q?), were observed in two cases each. Some other abnormalities were encountered, mostly in remission or relapse. The disappearance and repopulation of t(15q+; 17q?) cells were associated with complete remission and relapse, respectively, in two repeatedly analyzed cases.Including the previously reported cases, we investigated a total of 12 cases of APL, and all were found to be associated with t(15q; 17q?). The mean age of the 12 patients was 34.25 ± 3.12 (SD) years, and their mean survival 266.3 ± 95.67 (SD) days.     

Further studies on intestinal active transport during semistarvation

1. The effect of semistarvation (sufficient to produce a loss of 18-28% of initial body weight) on the active transport of D-glucose and L-histidine by the rat, the guinea-pig and the golden hamster has been investigated by the use of sacs of everted small intestine (from upper jejunum to lower ileum).2. In the rat and the guinea-pig the dietary restriction resulted in increased active transport in all regions of the small intestine. In contrast, it caused no alteration in active transport in the hamster.3. The response in the rat was most impressive in the middle-to-lower ileum during D-glucose uptake. Whereas normal sacs from this area appeared unable to move the sugar against its concentration gradient, sacs from semistarved rats did so quite well.4. Although there was a considerable loss (24-29%) of intestinal dry weight in all three species when the food intake was reduced, shortening of the small intestine was not detectable in the guinea-pig or the hamster and was present to only a minor extent in the rat.5. Evidence is presented indicating that the enhanced active transport is not merely a reflexion of the thinning of the intestinal wall and that it occurs during complete as well as in partial starvation.     

Further studies on fecal parasites in antiquity.

This is a continuation study of the survival of antigenic material over the centuries using mummified human remains from the Andean area of South America. The fluorescent antibody kit from Meridian Diagnostics (Cincinnati, OH) was used to identify some Cryptosporidium species and Giardia species found in feces from the intestines of mummies 500 to 3,000 years old. The specimens that were positive by direct visualization using fluorescent antibody were then tested with an enzyme-linked immunosorbent assay reaction using a Meridian kit just released on the market. Since all of the feces used were formed, it would seem that the organisms found were from carriers rather than active cases of disease. Similar fecal specimens were shown to harbor antigens from Helicobacter pylori almost 3,000 years old.     

Further studies on carrageenan-induced pleurisy in rats.

A study has been made of the exudate provoked by intrapleural carrageenan in rats. Various parameters have been measured including volume of exudate, numbers and types of cells. Pharmacological assay has shown the early release of histamine and 5HT into the exudate followed at later times by a release of prostaglandins, and a second release of histamine. The role of complement has been studied. Intrapleural injection of carrageenan after complement depletion produced a reduced migration of polymorphonuclear cells and also a reduction in volume of exudate. Prostaglandins remained unaffected by this treatment.     

Further studies on the anti-inflammatory effect of insulin

Experiments performed on rats showed that insulin, when applied i.v. or s.c., inhibited the foot edema induced by carrageenin, thermic effect of 45.7° C, compound 48/80 and 5-HT, but moderately increased the paw swelling evoked by kallikrein, a kinin-forming enzyme. The increased vascular permeability elicited by intradermal injection of histamine, 5-HT, bradykinin, PGE₁, carrageenin and compound 48/80 was also suppressed. The anti-inflammatory effect was not significantly altered by propranolol and adrenalectomy on the thermal and carrageenin edema, it was variably inhibited on the skin test, and was completely abolished on the paw swelling induced by 5-HT and compound 48/80. Since insulin had little or no effect on the vascular response when given topically together with the vasoactive agents, its complex effect on the acute inflammation appears to be brought about via indirect mechanisms.     

Further studies on Chara corallina virus

The particles of Chara corallina virus (CCV) and those of tobamoviruses share many properties, but differ in some. CCV particles are tubular, 532 nm long, and 18 nm wide, and are helically constructed with a basic pitch of 2.75 nm; their isoelectric point is pH 3.4–3.7; their sedimentation coefficient (s₂₀, w) is 230 S; they contain 5% RNA with a molecular weight of 3.6 × 10⁶ daltons, and with a base ratio of G 24.5, A 28.0, C 20.0, U 27.5; their coat protein is similar in size to that of tobamoviruses (about 17.5 × 10³ daltons). CCV is considered to be a tobamovirus. CCV may be transmitted experimentally to uninfected Chara corallina cells by injection of virus particles, and causes chlorosis and death in about 10–12 days. A classification of CCV and 68 other tobamovirus isolates, whose coat protein composition is known, showed that CCV is distant from all, but is most closely related to the cucurbit tobamoviruses.