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The stems of Jamaican chawstick, Gouania lupuloides, have yielded two novel 16,17-seco-dammaranoid saponins, designated gouanoside A [4] and gouanoside B [5]. Structural assignments are based on spectroscopic data including 2D nmr experiments on the corresponding aglycones, gouanogenin A [1] and gouanogenin B [3].

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Streptococci of the milleri group are part of the normal flora of human mucous membranes. These streptococci have also been reported to be significant pathogens. Like other mucosal streptococci, they may cause infective endocarditis; unlike other mucosal streptococci, however, they have also been repeatedly associated (more frequently in men than in women) with serious suppurative infections. Evidence for the pathogenicity of the Streptococcus milleri group is scattered and mainly circumstantial. Although the organisms are found in a high proportion of certain suppurative infections, other bacteria are often present as well. Successful treatment of these infections with surgery and broad-spectrum antibiotics is not indicative of any specific etiology. Only a few attempts at the induction of experimental infections other than endocarditis have been effective. Further investigation is required to establish the pathogenicity and pathogenic mechanisms of the S. milleri group.

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Electric non-invasive stimulation of the motor cortex was performed in 19 healthy subjects. Muscle responses were recorded with surface electrodes from the abductor, pollicis brevis and anterior tibial muscle. The mean central motor latencies for pathways regulating the function of the upper limbs was 4.5 msec (standard deviation 0.5 msec), the corresponding latency for the lower limbs was 9.6 msec (standard deviation 1.2 msec). The reproducibility of latencies and configuration of the potentials obtained indicates that the method described can be used as a reliable method in the diagnosis of affections of the motor system.

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The bacterial flora of the large intestine was examined in 35 laboratory-reared leopard frogs (Rana pipiens) subjected to one of the following four treatments: (i) normal feeding at 21 degrees C (10 frogs); (ii) fasting for 2 weeks at 21 degrees C (8 frogs); (iii) chilling for 1 week at 4 degrees C (9 frogs); and (iv) simulated hibernation for 3 weeks at 4 degrees C (8 frogs). Bacteria from the intestinal contents and mucosa were counted microscopically and by colony counting after strictly anaerobic culturing. The predominant bacteria were isolated and partially characterized. Fasting for 2 weeks produced no significant changes in total counts or in the types of bacteria cultured. Chilling, whether rapid or in the course of simulated hibernation, was associated with a decrease in the numbers and variety of bacteria. Thus it appears that the lowering of temperature rather than the absence of food is the important factor in the reduction of bacterial flora seen in hibernating frogs. However, the bacteria showed some adaptation to the low temperature, as the longer the host had been at 4 degrees C, the higher the proportion of bacteria which could grow when cultured at that temperature.

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The bacteria in the large intestines of 10 northern leopard frogs (Rana pipiens) were enumerated and partially characterized. Four nonhibernating frogs were collected in the summer, four hibernating frogs were collected in the winter, and two frogs just emerged from hibernation were collected in the spring. All frogs had about 10(10) bacteria per g (wet weight) of intestinal contents and about 10(9) bacteria per g (wet weight) of mucosal scraping, although the counts from the winter frogs were slightly less than those from the other two groups of frogs. Another group of 14 summer frogs, after treatment to induce hibernation, showed a drop in bacterial counts accompanied by a change in the composition of the flora. In most frogs, Bacteroides was the dominant organism. Other bacteria repeatedly isolated at high dilutions were strict anaerobes, including butyrigenic and acetogenic helically coiled bacteria; fusobacteria; and acetogenic, small, gram-positive bacilli. These data indicate that the intestinal flora of frogs is similar to that of mammals and birds and that this flora can be maintained at temperatures close to freezing.

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Gene D5 is not only necessary for replication of bacteriophage T5 DNA and for shutoff of expression of some early genes, but has been found to be necessary also for the expression of late T5 genes. The polypeptide product of gene D5 has been identified, an intragenic map of gene D5 has been constructed, and the direction of transcription of gene D5 has been established. The polypeptide coded by gene D5 has been shown to be a DNA-binding protein with affinity for both double- and single-stranded DNA.

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The predominant gram-positive bacteria in 47 fecal specimens from 10 healthy men were studied by microscopic and cultural counts, by the characterization and tentative identification of isolates, and by the use of fluorescein isothiocyanate (FITC)-conjugated globulins prepared using some of the isolates. Gram-positive bacteria averaged 10(10.5+/-0.4(sd)/g (wet weight) of feces with significant variation from host to host. Characterization of 865 isolates, all strict anaerobes and carbohydrate fermenters, showed 12 to 39 distinguishable strains from each host and indicated that some strains were present the full period of about 18 months. Sixty percent of the isolates belonged to one of five types, tentatively identified with five species-Bifidobacterium adolescentis, Eubacterium aerofaciens, E. rectale, Peptostreptococcus productus, and Ruminococcus bromii. There was distinct host idiosyncrasy in the pattern of estimated counts of these five types. Certain strains resembling B. adolescentis, E. aerofaciens, and P. productus, distinguished with FITC conjugates, were resident in their hosts for many months. In direct smears each strain constituted about 1% of the total bacteria.

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Antimicrobial agents were added to the feed of swine for three weeks to determine the interrelationships of potentially pathogenic agents in the nasal tract, turbinate atrophy and weight gains. Bordetella bronchiseptica was not isolated from the groups fed the combination of chlortetracycline, penicillin and sulfamethazine. B. bronchiseptica was found in some pigs after the feeding trail, but this organism was not significantly associated with turbinate atrophy at the time of slaughter.Mycoplasma hyorhinis was not found in the nasal passages of the pigs that received feed containing high concentration chlortetracycline but was found in pigs that received other diets. Hemophilus suis was not significantly reduced by any of the treatments used. The organisms studied in the pigs were not isolated from the personnel handling the pigs.

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Diarrhea, reduced appetite, and nervousness were observed following oral exposure of six pigs to freeze-thaw extract and living culture of E. coli strain 0139:K82:H1. The most significance gross change was the appearance of subserosal edema of the mesentry, especially of the mesocolon. Histological findings included perivascular edema of the brain and reticulum cells as well as lymphocytic aggregates in the renal cortex simulating early neoplasia. Edema of the submucosa of gallbladder, the duodenum, the spiral colon and the fundic stomach as well as the lymph nodes was also observed. The syndrome which was produced resembled, in many aspects, edema disease although some complicating factors were ob-

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Twenty-two pigs were inoculated parenterally with various E. coli 0139:K82:H1 preparations. Clinical signs of disease in pigs injected with freeze-thaw extract consisted of early listlessness, diarrhea and, later, hyperirritability of varying intensity in some animals.Hemorrhagic gastroenteritis involving the duodenum, spiral colon and the fundic portion of the stomach, and ulceration of the fundic stomach were observed at post-mortem examination of pigs inoculated parenterallly with living culture or freeze-thaw extract. No significant lesions were observed in pigs inoculated with ultrasonic or hypotonic acid-saline extract. In pigs injected with living culture or freeze-thaw extract, the histological alterations consisted of moderate perivascular edema of the brain, marked hepatic parenchymal cell degeneration, hepatic subserosal edema and "toxic" lymph nodes, when compared to the control group.

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