Raymond L. Hayes

Relationship of Vibrio Species Infection and Elevated Temperatures to Yellow Blotch/Band Disease in Caribbean Corals

ABSTRACT The bacterial and temperature factors leading to yellow blotch/band disease (YBD), which affects the major reef-building Caribbean corals Montastrea spp., have been investigated. Groups of bacteria isolated from affected corals and inoculated onto healthy corals caused disease signs similar to those of YBD. The 16S rRNA genes from these bacteria were sequenced and found to correspond to four Vibrio spp. Elevating the water temperature notably increased the rate of spread of YBD on inoculated corals and induced greater coral mortality. YBD-infected corals held at elevated water temperatures had 50% lower zooxanthella densities, 80% lower division rates, and a 75% decrease in chlorophyll a and c2 pigments compared with controls. Histological sections indicated that the algal pyrenoid was fragmented into separate segments, along with a reconfiguration and swelling of the zooxanthellae, as well as vacuolization. YBD does not appear to produce the same physiological response formerly observed in corals undergoing temperature-related bleaching. Evidence indicates that YBD affects primarily the symbiotic algae rather than coral tissue.

INTRACELLULAR CRYSTAL-BEARING VESICLES IN THE EPIDERMIS OF SCLERACTINIAN CORALS, ASTRANGIA DANAE (AGASSIZ) AND PORITES PORITES (PALLAS)

Orthorhombic aragonitic crystals, embedded with a granular lipo-protein matrix and surrounded by a trilaminar membrane, are localized in the apical cytoplasm of epidermal cells of Scleractinian corals. Adult specimens of Astrangia danae (Agassiz) and settled planulae of Porites porites (Pallas) contain crystals averaging 0.7 mu by 0.1 mu by 0.3 mu within Golgi-derived vesicles. Short-term labelling with 45Ca reveals distribution of radioactivity amont a basic tissue fraction (92%) an acid tissue fraction (5%) and a skeletal fraction (3%). Identification of the primordial crystal population within membrane-bound visicles provides overwhelming evidence for the intracellular mode of calcification in Scleractinia. Moreover, it permits development of a novel concept of cellular regulation over these dynamic events. The membrane-bound vesicel is a miniature crystal fabrication station and a vehicle responsible for transportation of seed crystals and an organic matrix material to sites of discharge from the cell. The vesicle membrane becomes a probable locus of active transport and enzymatic activity as well as a physical barrier to be penetrated for release of vesicle contents into the extracellular milieu. Contact between the vesicle membrane and the plasmalemma would result in exocytosis and the onset of skeletogenesis. Principles governing crystal growth would prevail from then on. The released crystal becomes a nucleation catalyst and the organic matrix, a supply of ionic calcium for self-limiting crystallization. Crystals are produced by the organism spontaneously and continuously from shortly after larval attachment throughout the life of the polyp. Therefore, these membrane-bound vesicles signal the dynamic process by which initiation, differentiation, growth and limitation of the coral skeleton is regulated.

Adenocarcinoma of the pancreas metastatic to the mandible.

I t is generally agreed today that metastatic tumors of the jaw occur more frequently than was formerly believed. These lesions are of great clinical importance, since their appearance in the jaw may be the first indication of an undiscovered malignancy which might exist in an unknown and distant primary site. This was true in the case that is being reported here. Among the carcinomas that have been known to metastasize to the jaws, the more common primary sites have been the breast, prostate, kidney, lung, thyroid gland, and gastrointestinal tract. The primary site of the tumor being reported here was the pancreas. Anderson1 states that only 2 per cent of all carcinomas are found in the pancreas, with the majority of these occurring in the head of the organ. Carcinoma of the tail of the pancreas is less commonly found. Clinically, carcinoma of the pancreas head is usually associated with obstruction of the common bile duct, accompanied by painless and ever-deepening jaundice, wasting, weakness, and clay-colored stools. Carcinoma of the tail of the pancreas usually is not accompanied by these symptoms. However, it is associated with earlier and more widespread extension and metastasis. Also, widespread venous thrombosis, especially of the lower extremities, and dccpseated pain may bc found in these cases2, 3

Histological Study of the Dentition of Tautoga onitis

The teeth of the fish Tautoga onitis resemble human teeth in gross appearance and histological composition. In the coronal part of the root connective tissue fibers were inserted into the cementum. Bone was fused or ankylosed with cementum externally and fused with dentin internally, There was no identifiable true periodontal membrane in anterior or posterior teeth.