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Intravenous immunization with a cell extract of Mycobacterium lepraeproduced a primary immune response of considerable magnitude, followed by an equally large response after secondary stimulation, as measured by assay of plaque-forming cells (PFC). Infection with M. lepraeor immunization with cell extract by the footpad route produced a lower level of response than that seen in the intravenous group. Identical patterns of response, although not of the same magnitude, were observed after both primary and secondary challenges in the two footpad groups, one infected with viable M. lepraeand the other immunized with M. lepraecell extract. The secondary response after a booster dose to all these groups appeared to be an enhanced immunoglobulin M response. Control studies confirmed that the immune response was a direct result of the host-parasite interaction and that the PFC observed resulted from stimulation of antibody-forming cells by antigens of M. leprae.The similarity in time of appearance of peak PFC levels in the two footpad groups may be attributed to the live challenge passing through a latent phase. Alternatively, the challenge is known to contain a large proportion on nonviable cells, and it may also contain soluble M. lepraeantigens. Studies of the cross-reactivity of the antigens have extended previous observations on antigens shared between M. lepraeand other mycobacterial species. Use of the two antigen-containing fractions of the M. lepraecell extract has suggested that one of the fractions contains some shared antigens, whereas the other has an antigen specific to M. leprae.

The effect of level of protein intake on urinary and fecal calcium and calcium balance of nine young adult human males was investigated. Calcium intake was 500 mg daily and protein intake was varied from 47 to 95 to 142 g daily. When the protein intake was 47 g daily, the mean calcium retention of the subjects was 31 mg, with only two subjects showing a slight negative balance. When the protein intake was 95 and 142 g, respectively, the mean calcium balance was -58 and -120 mg, and no subject was in calcium balance. Increasing the intake of fruits and vegetables by 50% had no beneficial effect on calcium balance. The urinary calcium increased significantly with each increase in protein intake, the mean value being 168, 240, 301 and 278 mg, respectively, when the low, the medium and the high protein and the high protein-high fruit and vegetable diet was given. Fecal calcium was not significantly affected by protein intake.

Glucose stimulates the high-affinity processes of chloroquine and amodiaquin accumulation in owl monkey erythrocytes infected with a chloroquine-susceptible strain of Plasmodium falciparum. Although these erythrocytes have greater ability to accumulate amodiaquin than chloroquine, glucose has relatively less effect on amodiaquin accumulation than on chloroquine accumulation. In contrast to these findings with chloroquine-susceptible P. falciparum, glucose stimulates amodiaquin but not chloroquine accumulation in erythrocytes infected with chloroquine-resistant P. falciparum. This lack of function of a substrate-dependent component of chloroquine accumulation distinguishes chloroquine-resistant from chloroquine-susceptible P. falciparum.

An integral representation is given for the product of two Jacobi polynomials. It is also shown how this formula can be extended to yield integral representations for the product of two generalized hypergeometric polynomials. The main results (16), (25) and (30) below are believed to be new.

A study was carried out on the causes of liquefaction of tamarind kernel (TK) paste used in jute warp sizing. Mill- decomposed pastes, added as inocula to fresh paste, strongly liquefied the latter under aerobic as well as crudely anaerobic conditions. Aerobic bacteria isolated from mill pastes were mostly unable to liquefy, either singly or jointly. On the other hand, 9 of the 11 fungal species tested (some isolated from mill pastes) caused strong liquefaction. The enzymes in the crude filtrates of some of these liquefied TK paste at a faster rate than mineral acids at boil. In laboratory experi ments simulating mill conditions of sizing, these results were generally confirmed, fungal action being much stronger than bacterial. Aspergillus fumigatusand its enzyme were the most potent. Accumulated fungal enzymes appear to be the chief cause of liquefaction in mills. While the strongly liquefying fungi could be inhibited by small doses of common antiseptics, these had little effect on their enzymes. Sodium sulfide at 0.16% concentration inhibited all these enzymes.

A technique has been developed for detecting fungal growth on and inside the jute fiber by the differential staining of hyphae and fibers with Chlorazol Sky Blue stain. The test is also applicable to cotton. Growth inside the lumen is not a universal feature of fungal attack on jute, although nearly all the dark-colored fungi tested showed this property. which is not ordinarily lost or gained by changing external conditions of growth or by modifying the fiber. The minimum period required for lumen invasion has been found to be different for different species. Some of these fungi showed com paratively weak growth within the cotton fiber. Fungi growing within the lumen of jute seem to penetrate the fiber cell wall apparently at random, not at weak points nor through open ends. The active organisms attacking jute under different practical con ditions of damage have been found to be different. Granular bodies sometimes seen within the lumen of raw jute have been isolated and traced to a Bacillusspecies.

In a study of the structural changes brought about in the jute fiber by fungal attack, generally a correlation was found between such change, on the one hand, and growth inside the lumen and fiber damage, on the other. Cracks across the fiber cells were a common feature, and complete breaks were sometimes found. External surface damage was never seen except in a few mill-damaged samples, although ultimate cells pre separated before attack showed such damage. Internal damage along the lumen was noted in samples which showed lumen growth, and sometimes even with species not growing within the fiber. Soil bacteria caused cracks across the cell, as well as internal and external corrosion. Damage caused by fungal culture filtrates was often different from and less intense than that in in vivo attack, although with preseparated Jute ulti mates complete dissolution was sometimes seen.