Deep crustal drilling in the north atlantic ocean.

Oceanic crustal drilling by R. V. Glomar Challenger at 15 sites in the North Atlantic has led to a complex picture of the upper half kilometer of the crust. Elements of the picture include the absence of the source for linear magnetic anomalies, marked episodicity of volcanic activity, ubiquitous low temperature alteration and evidence for large scale tectonic disturbance. Comparison sections in the Pacific and much deeper crustal drilling are needed to attack problems arising from the North Atlantic results.

Crustal Spreading in Southern California: The Imperial Valley and the Gulf of California formed by the rifting apart of a continental plate.

The current excitement among geologists and geophysicists stemming from the "new global tectonics" has led to a widespread, speculative reinterpretation of continental geology. The Gulf of California and its continuation into the Imperial Valley provide an excellent opportunity for studying the border zone between the North American and Pacific plates, and an interface of continental and oceanic tectonics. The Salton trough, the landward extension of the gulf, is a broad structural depression, comparable in size with the deeper marine basins of the southern part of the gulf, but here partially filled with sediments deposited by the Colorado River.

Age of the floor of the eastern Indian ocean.

Deep sea drilling in the eastern Indian Ocean shows that the oceanic crust off Western Australia is approximately 140 million years old and becomes younger to the west; this dates the initial opening of the Indian Ocean.

Electron spectroscopic imaging for high-resolution immunocytochemistry: use of boronated protein A.

In the present study we adapted electron spectroscopic imaging (ESI) for high-resolution immunocytochemistry. To accomplish this, we applied boronated protein A (B-pA) for indirect detection of specific antigenic sites using pre-embedding and post-embedding protocols. Isolated acinar cells were exposed to wheat germ agglutinin (WGA) and anti-WGA, followed by B-pA, to reveal WGA binding sites at the level of the plasma membrane. The cells were then embedded in Epon and unstained ultra-thin sections were examined by electron microscopy using the ESI mode. For post-embedding, ultra-thin sections of glutaraldehyde-fixed, Lowicryl-embedded pancreatic tissue were exposed to specific antibodies (anti-insulin or anti-amylase), followed by B-pA. The unstained sections were examined using the ESI mode. In both cases, boron was detected with high resolution either at the level of the plasma membrane of acinar cells, demonstrating WGA binding sites, or over secretory granules in pancreatic insulin-secreting cells or acinar cells, demonstrating insulin and amylase, respectively. These findings were compared to those obtained with the protein A-gold technique, and have demonstrated the analogy of both types of labeling. In addition, several control experiments assessed this novel approach. They have demonstrated the specificity of labeling and the high reactivity of B-pA, as well as its antibody-binding properties. Finally, electron energy loss spectral analysis confirmed the presence of boron in the tissue sections at sites where immunolabeling was detected. These results demonstrate that ESI is an appropriate approach for cytochemistry. Since the technique is based on detection of elements, spatial resolution is considered to be in the magnitude of 0.5 nm, which represents a major improvement in resolution over actual electron microscopic cytochemical techniques.

Cryptosporidial infections in captive wild animals.

Neonatal diarrhea was an important cause of morbidity and mortality in a hand-rearing facility for exotic ruminants at the San Diego Wild Animal Park. Studies undertaken to determine the causes of the problem revealed that oocysts of Cryptosporidium sp. were demonstrable in auramine O stained fecal smears from 52 of 183 (28.4%) animals examined. Cryptosporidial infection was identified in 21 of 40 species of exotic ruminants with diarrhea. In addition, cryptosporidia were associated with gastroenteric disease in two primates and two reptiles. It was observed also that auramine O stained coccidial oocysts of the genus Eimeria, which were present in five of 183 (2.7%) of the specimens examined.

Endodontic surgery for treatment of a fistulated molar abscess in an orangutan.

An adult Bornean orangutan was treated for bacterial labyrinthitis, which was a sequela to a molar abscess and maxillary sinusitis. Antibiotic therapy and endodontic surgery led to complete remission of clinical signs.

Glucosuria associated with renal calculi in Asian small-clawed otters.

Urine from one female and 2 male Asian small-clawed otters (Aonyx cinerea) with bilateral renal calculi, one female with unilateral calculi, and one nonaffected male were evaluated for abnormal urinary crystalloid excretion. One otter with bilateral renal calculi had cystic calculi composed of calcium oxalate monohydrate and dihydrate. The 2 affected males were littermates, as were the 2 affected females, but the 2 litters were from different parents. At the time of the study, the otters did not have clinical signs of disease. Hematologic and serum biochemical, electrolyte, and enzyme values were normal. The urinary excretion of calcium, oxalate, uric acid, phosphate, citrate, and amino acids in otters with renal calculi was similar to that of the nonaffected otter. The 4 otters with renal calculi had glucosuria but the nonaffected otter did not have glucosuria. The glucosuria, in the absence of hyperglycemia, suggested a renal tubular transport defect for glucose. Other renal abnormalities were not found.

Intrauterine fetal demise associated with consumption coagulopathy in a Douc langur monkey (Pygathrix nemaeus nemaeus).

Intrauterine fetal demise was suspected in a Douc langur monkey based on measurements of declining urinary estrogen levels. Additional clinical evaluation by fetal cardiac auscultation, ultrasonic instrumentation, radiologic examination, and amniocentesis supported the diagnosis. Blood clotting studies demonstrated deficiency of factors consistent with a diagnosis of consumptive coagulopathy, a syndrome identical to that observed in man following prolonged intrauterine fetal demise.

Treatment of pulmonary acariasis in rhesus macaques with ivermectin.

Rhesus monkeys were treated for pulmonary acariasis with single injections of ivermectin (200 micrograms/kg). Monkeys were killed and complete necropsies performed. Control monkeys had numerous live mites, while treated monkeys had only dead, frequently fragmented mites. Histopathologically, inflammatory lesions were most severe in control monkeys and monkeys killed one week after treatment. Inflammatory changes progressively decreased with increasing time post treatment.