Platelets processed for transfusion are routinely subjected to centrifugation, mechanical agitation and storage at either room temperature or 4 C. To evaluate morphologic changes associated with standard blood bank conditions, platelet units were grouped into four categories: linear agitation at room temperature, agitation at a 90 degrees arc with a Hemolater at room temperature, agitation at a 360 degrees arc with a commercial platelet agitator, and refirgeration at 4 C without agitation. Cold (4 C) preservation resulted in a surprisingly good preservation of platelet ultrastructure, even at 72 hours of storage. By contrast, harsh linear agitation at room temperature brought about marked alterations in platelet ultrastructure beginning at 24 hours. The Hemolator agitator with 90 degrees arc was associated with good preservation of platelet organelles even at 72 hours, whereas marked degenerative changes were observed at this time in platelets processed with a commercial agitator with a 360 degrees arc. These results indicate that platelets stored at 4 C or processed at room temperature with an agitator with 90 degrees arc show the best preservation of ultrastructure.

Blood Banks↗

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Dual differentiation in small cell carcinoma (oat cell carcinoma) of the lung.

Two cases of small cell "undifferentiated" carcinoma (oat cell carcinoma) of the lung with dual neurosecretory and squamous differentiation are reported. One was treated with various regimens of chemotherapy and radiotherapy; the other was untreated at the time of biopsy. By electron microscopy, the same tumor cells showed membrane-bound, dense-core, neurosecretory-type granules and bundles of tonofibrils denoting squamous differentiation. This dual differentiation underlies the difficulty of ascribing an exclusively neural histogenesis to small cell carcinomas with neurosecretory-type granules. It is possible that entoderm-associated neuroectodermal tumors develop features of autochthonous entodermal tumors as a result of microenvironmental influences. An alternative hypothesis would be that small cell tumors are derived from basal reserve bronchoepithelial cells with pluripotentialities.

Aged↗

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Nuclear and cytoplasmic inclusions in disseminated human cytomegalovirus infection.

A case of disseminated human cytomegalovirus infection is described in a full-term female who expired 3 1/2 h after birth. Cytomegalic inclusions, both intranuclear and intracytoplasmic, were observed mainly in the kidneys, liver, lungs, and anterior pituitary but were not seen in the bone marrow and spleen. Whereas the nuclear inclusions consisted of an amorphous filamentous meshwork with a variable number of pleomorphic capsids, the cytoplasmic inclusions were composed of membrane-bound aggregates of mature virions with dense cores and multilayered envelopes. The complex envelopment process of cytomegalovirus appears to involve successive coats derived from the nuclear membrane and from the endoplasmic reticulum or cytoplasmic vesicles.

Bronchi↗

PubMedDate not supplied

Experimental plasmacytomas in relation to human multiple myeloma.

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Animals↗

PubMedDate not supplied

Human tumor xenografts in athymic (nude) mice: chemotherapy trials in serially transplanted tumors.

In a total of 38 consecutive attempts at transplanting freshly excised malignant human neoplasms in athymic nu/nu mice during the past year, 12 resulted in successful xenografts. To date, all of these have been subsequently transplanted for two or more generations. These successful xenografts include two squamous cell carcinomas of the head and neck, three squamous cell carcinomas and one undifferentiated large cell carcinoma of the lung, three adenocarcinomas of ovarian or endometrial origin, and one carcinoma of each of the following sites: urinary bladder, stomach, and colon. Chemotherapy trials on three different squamous cell carcinomas serially transplanted in nude mice revealed three different degrees of sensitivity to bleomycin. One tumor which was markedly sensitive to bleomycin showed only a slight response to cis-diamminedichloroplatinum (II). These chemotherapy trials will be expanded to wider panel of transplantable human squamous cells cacinomas of different origins with anti-tumor agents used singly or in combination.

Animals↗

PubMedDate not supplied

Immunohistochemistry of hepatocellular carcinoma associated with cirrhosis.

Tumor cell marker antibodies were used to analyze ten cases of hepatocellular carcinoma associated with cirrhosis. Clinically, eight of these cases gave a history of chronic alcoholism and the other two of hepatitis B virus infection. Formalin-fixed, paraffin-embedded sections from these cases were screened with antibodies against alpha fetoprotein (AFP), hepatitis B surface antigen (HBsAg) and carcinoembryonic antigen (CEA) using the peroxidase antiperoxidase and avidin-biotin immunoperoxidase procedures. Three cases were positive for AFP, four for HBsAg, and three for CEA; two cases had both HBsAg and CEA. Alpha fetoprotein was present only in the cytoplasm of tumor cells in three cases. Hepatitis B surface antigen, on the other hand, was present in the cytoplasm of hepatocytes in cirrhotic areas and, in one out of the four cases, was also present in hepatocellular carcinoma cells. Carcinoembryonic antigen was seen in three cases; it was present on the surface and in the cytoplasm of proliferating ducts within the cirrhotic areas and between cell surfaces of individual tumor cells in two cases. The presence of different markers was not related to the microscopic appearance of the tumors. In one case, positivity for AFP was of diagnostic help in a tissue sample obtained by needle biopsy. The avidin-biotin immunoperoxidase procedure was more sensitive than the peroxidase antiperoxidase (PAP technique in the pathological assessment of autopsy specimens. Our findings are in agreement with those of other reports and indicate that AFP and HBsAg are the most commonly found markers in hepatoma associated with cirrhosis, and that CEA staining is variable and hepatoma associated with cirrhosis, and that CEA staining is variable and probably non-contributory.

Adult↗