Immunohistochemical and ultrastructural investigation of acinar cells in submandibular and sublingual glands of rats fed a liquid diet.

In atrophic parotid glands induced by liquid diet, acinar cell apoptosis is increased while proliferative activity is reduced. This study aimed to clarify how liquid diet affects submandibular and sublingual glands, including acinar cell apoptosis and proliferation. Seven-week-old male Wistar rats were fed either a liquid (experimental group) or pellet diet (control group) from 3 to 21 days, respectively. Submandibular and sublingual glands were weighed and examined histologically, ultrastructurally, and immunohistochemically using antibodies to cleaved caspase-3 (Casp-3) and 5-bromo-2'-deoxyuridine (BrdU). Weights of submandibular and sublingual gland from the experimental group were not significantly different from controls at any time point. Histological and ultrastructural characteristics of experimental acinar cells in both glands were normal. Acinar cells in control and experimental submandibular glands were positively stained with periodic acid Schiff (PAS) and weakly stained by alcian blue (AB). In control and experimental sublingual glands, mucous acinar cells were PAS-positive and strongly AB-positive. Although Casp-3- and BrdU-positive acinar cells were identified in both glands in the experimental group, their labeling indices were not significantly different from controls. In conclusion, liquid diet in rats does not induce atrophic alterations to acinar cells, including apoptosis and proliferative activity in submandibular and sublingual glands.

A case of angiocentric immunoproliferative lesions (angiocentric lymphoma) associated with human T-cell lymphotropic virus type 1.

We report a case of angiocentric immunoproliferative lesions (AILs; angiocentric lymphoma) in the subcutaneous tissue associated with human T-cell lymphotropic virus type 1 (HTLV-1). The patient showed an indolent cutaneous manifestation for 9 years until death. A skin biopsy revealed an angiocentric infiltration of atypical T lymphocytes and a marked coagulative necrosis, which are histologic hallmarks of AILs. Human T-cell lymphotropic virus type 1 antibody was detected by the indirect immunofluorescence test. The proviral integration of HTLV-1 also was confirmed in a DNA extract from paraffin sections using the polymerase chain reaction. The Epstein-Barr virus genome, which has been reported to be associated with AILs, could not be detected by polymerase chain reaction. The present case indicated that HTLV-1 also should be considered one of the pathogenetic factors of AILs.

Ultrastructural studies of eosinophils in passive cutaneous anaphylaxis.

Kinetics and ultrastructural changes of eosinophils in passive cutaneous anaphylaxis in guinea pigs were studied. Ovalbumin was used. Skin biopsies were studied with the electron microscope. Degranulation of eosinophils in the vascular lumen, the vascular wall, and in the surrounding of vessels was noted. There was edema and degeneration of collagen fibers.

Genetic studies of hybrids between coliphage lambda and salmonella phage P22: genetic analysis of the P22-lambda hybrid class.

P22-lambda hybrids which retain the protein coat of P22 have been isolated and characterized into two types. Type 1 hybrids which have the c through O-P genes of lambda are unable to grow lytically on Salmonella typhimurium. On the other hand, type 2 hybrids which contain only the c region of lambda, plated on S. typhimurium. Both hybrid types retained the generalized transducing and antigenic conversion capabilities of P22.