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X-ray diffraction, Mössbauer spectroscopy, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) techniques were used to characterize the Fe-C phases in the soots synthesized by the DC arc discharge method. Various equilibrium and non-equilibrium Fe-C compounds were identified, with fractions depending on both the location in the reactor and the helium gas pressure. The soots obtained are composed of the same five phases (C-graphite, α-Fe, γ-Fe, Fe3C and Fe5C2) whatever the helium gas pressure and wherever they are situated in the reactor. However, the location in the reactor has a considerable influence on the size of the particles in the nanostructure. The Fe-C compounds in the Pyrex vessel samples (CL) seem only to be present in the form of nanoparticles embedded in an amorphous gangue, while the water-cooled copper cylinder samples (RS) contain, in addition to these nanoparticles, large composite crystalline particles.

Objective and design:Interleukin-1 (IL-1), tumor necrosis factor-α (TNF-α), and matrix metalloproteinases (MMPs) play important roles in the pathogenesis of osteoarthritis (OA). In the present study, using Affymetrix oligonucleotide array technology and real-time quantitative RT-PCR we have investigated the molecular mechanisms underlying the differential effect of IL-1 and TNF-α on gene expression in the human chondrosarcoma cell line, SW1353. Materials and methods:SW1353 cells were stimulated singularly with IL-1α, TNF-α, Phorbol 12-myristate 13-acetate (PMA), or treated with the combination of cytokine and PMA. Total RNA was collected at multiple time points over a 24-h period followed by biotinylated cRNA target preparation and hybridization onto the Affymetrix HG-U95Av2 array. The differential expression patterns of several cytokine and MMP genes were further confirmed by real time quantitative RT-PCR, Western blot, and ELISA. Results:Our microarray experiments have broadly confirmed previously published data on chondrocyte gene expression regulated by IL-1 and TNF-α. The expression pattern of proIL-1β, MMP-1, and MMP-13 in chondrocytes is differentially regulated when stimulated with proinflammatory cytokines. IL-1, but not TNF-α, can induce IL-6, bone morphogenic protein 2 (BMP-2), and cyclooxygenase (COX-2) expression in SW1353 cells. Additionally, our Western blot results provide the first evidence that IL-1β is produced in the proform in IL-1α-activated chondrosarcoma cells and that additional signals are required for its posttranslational processing/activation. Conclusions:IL-1 and TNF-α each activate a distinct set of genes in chondrosarcoma cells, and gene expression in these cells is regulated by groups of genes related in part by their function. Chondrocyte IL-1α appears to serve an important role in the pathogenesis OA contributing to joint inflammation and cartilage destruction.

Measurements of the inelastic neutron scattering from liquid4He atT=1.2 K in the range of wavevector transfer 3=Q=12 Å-1 have been performed to verify the oscillations in the peak position and the width of the scattering function withQ observed by Cowley and Woods and by Martelet al. We confirm these oscillations and extend the measurements to show that the oscillations in the width continue up toQ˜12 Å-1 while oscillations in the peak position, which have a much smaller amplitude, could be observed with confidence up toQ˜8 Å-1 only. We also present a straightforward RPA calculation of the dynamic form factorS(Q, ?), beginning from the pair interatomic potential, to see how well the observedS(Q, ?) can be described and to investigate the origin of the oscillations. The observedS(Q, ?) is quite well reproduced and the oscillations in the width and peak position ofS(Q, ?) are seen to originate from oscillations in the interaction in the RPA which we have approximated as the4He-4He scattering amplitude calculated fromv(r). While the present calculation is quite different from the model proposed previously by Martelet al., the physical origin of the oscillations inS(Q, ?) is the same, namely oscillations in the4He-4He atom scattering amplitude.

The microscopic theory of3He-4He mixtures with a Bose condensate is formulated in terms of the dielectric formalism. By expressing all correlation functions in terms of proper, irreducible contributions, one sets the stage for approximate calculations that will be consistent with various exact sum rules and Ward identities, just as in the case of pure4He. The present analysis includes a symmetry-breaking term that allows us to deal with the continuity equations properly, and is valid at finite temperature. As a specific application, we express the normal fluid density ?N in terms of the static4He current-current correlation function. We also give the first formal proof that in the presence of a moving condensate, the3He atoms make no direct contribution to the superfluid flow.

The attenuated bacillus Calmette-Guérin (BCG) vaccine strain is derived from a virulent strain of Mycobacterium bovis. BCG is difficult to differentiate from other strains of M. bovis and other members of the M. tuberculosis complex by conventional methods. Recently, a genomic region designated RD1 was found to be present in all virulent M. bovis and M. tuberculosis strains tested but deleted from all BCG strains tested. With this information, a multiplex PCR method was developed to detect the RD1 deletion. A large collection of BCG and other M. tuberculosis complex strains from diverse host and geographic origins was tested. RD1 was deleted in 23 of 23 BCG strains. RD1 was present in 129 of 129 other M. tuberculosis complex strains. This multiplex PCR method can be used as a tool for the rapid and specific identification of BCG.

Pyrazinamide (PZA) is one of the three most important drugs for treatment of Mycobacterium tuberculosis infections. The antibacterial activity of PZA requires a bacterial enzyme, pyrazinamidase (PZAase), which hydrolyzes PZA to form pyrazinoic acid and ammonia. Most PZA-resistant clinical M. tuberculosis isolates lack PZAase activity. With the goal of eventually identifying and characterizing the M.tuberculosis PZAase gene, we began with the more tractable organism, Escherichia coli, which also has PZAase activity. We screened a transposon-generated E. coli insertion mutant library, using a qualitative PZAase assay. Two PZAase-negative mutants out of 4,000 colonies screened were identified. In each mutant, the transposon interrupted the same 639-bp open reading frame (ORF), ORF1. The expression of ORF1 on a multicopy plasmid complemented a PZAase-negative mutant, leading to PZAase activity levels approximately 10-fold greater than those of the wild type. PZA has a structure similar to that of nicotinamide, a pyridine nucleotide cycle intermediate, so we tested our strains for nicotinamidase activity (EC 3.5.1.19) (genetic locus pncA). The construct with multiple plasmid copies of ORF1 had an approximately 10-fold increase in levels of nicotinamidase activity. This overexpressing strain could utilize nicotinamide as a sole nitrogen source, through wild-type E. coli cannot. We conclude that a single E. coli enzyme accounts for both PZAase and nicotinamidase activities and that ORF1 is the E.coli PZAase and nicotinamidase gene, pncA.

The objections that have been raised against the prolonged administration of iodide in small doses are conspicuously unsupported by trustworthy evidence. The alleged deleterious effects are not clearly defined. The disturbing effects sometimes attributed to the use of iodide or iodine in the treatment for abnormalities of the thyroid may be due to the disease and not to the iodide. With the exception of the well known changes in the thyroid gland during hyperplasia and in cases of simple goiter and certain changes in the metabolism, important alterations in other organs and functions as a result of small doses of iodide have not been demonstrated. Marine's1 statistical studies of clinical data indicate the lack of evidence of the alleged deleterious effects of iodide, and recently Read, Walker and McKenney2 failed to demonstrate any effects on the pulse rate in human subjects observed during relatively short periods. Clinical data, however, could

This disease is evinced by simple inflammation of gums around the teeth, followed by chronic inflammation with or without suppuration, with or without calcic deposits, a gradual destruction of the peridental membrane, with recession and absorption of the alveolar process and gums, concluding with loosening and exfoliation of the teeth. The physician is more familiar with this disease, as it appears to him as a consequence of scurvy, mercurial or iodid salivation.Few diseases have received as many names as that under discussion. More time has been spent in apology for and discussion of new names than in original research as to its etiology. The term pyorrhea alveolaris, which has become so popular, and which I have selected for the title of this paper, does not elucidate the exact condition, since many cases which come to the dentist do not suppurate.Riggs's disease seems a more appropriate title, since to

The mutuality of interest involved in their studies of the degenerate classes, has led the authors of this paper to combine their observations in a joint paper. This paper, however, is too lengthy for presentation to this Section. We have, therefore, abridged the subject-matter as far as possible, with the view of presenting only the most important features of the essay, reserving its complete publication until some future time.The present paper comprises a portion of an address upon "The Skulls of Criminals," with cuts of the more important specimens, delivered by Dr. Lydston, at the meeting of the Mississippi Valley Medical Association, September 11, 1890, together with some of Dr. Talbot's studies of the jaws of the degenerate classes, and deductions drawn from an extensive series of cooperative studies of criminals. No attempt has been made to formulate an arbitrary theory regarding the crime class. Indeed, it is the

The subject of the etiology of irregularities of the teeth is so comprehensive and so replete with points of interest, that it is obviously impossible for one to enter into minutiæ within the limits of a single paper. I have therefore deemed it best to prepare a series of papers, in which an attempt will be made to present in an intelligible manner the conclusions formed during an extensive experience in the examination and study of the mouths of strong and well constituted persons, of the mouths of the insane, idiotic, deaf and dumb, and blind, and of models of various deformities of the jaws and teeth. In the present paper—the first of the series—attention will be given to such irregularities as are developed coincidently with the growth of the skeleton; these being, as is well known, chiefly connected with the superior maxilla.Irregularities of the teeth may be classed

The following autopsy was made on an old man, in whose case the pathologic diagnosis was as follows: Senile marasmus (senile emphysema, senile sclerosis of the aorta, atrophy of the parenchymatous organs), scurvy (hemorrhagic gingivitis); chronic aortic and mitral endocarditis; fibrous myocarditis; chronic nephritis; caseo-calcareous areas in the right apex, spleen and left adrenal; double hydrothorax; bronchitis; fibroma of the stomach; amputation of the left lower extremity at the lower third of the thigh. The findings unrelated to the scope of the present investigations are omitted. The gums were found swollen, and here and there infiltrated with blood. There was purulent matter about the roots of the teeth, many of which were loosened and some of which could be removed with the fingers. The roots of the loosened teeth were covered with a granular, grayish material.Only the lower frontal teeth and corresponding part of the jaw could be examined.

Scurvy is a disease characterized by simple inflammation of the gums which gradually becomes chronic and deep-seated, and extends throughout the alveolar process causing its absorption and exfoliation of the teeth. This disease has passed under various designations: salivation, bromidism, plumbism, iodism, pyorrhea alveolaris, phagadenic pericementis, ptyalism and interstitial gingivitis. These terms merely define local manifestations in connection with other symptoms. The term interstitial gingivitis defines the precise pathologic change which occurs in the tissues.Pathologic material for the study of scurvy in man is obtained with such difficulty in the recent state as to necessitate research upon animals. As the first step in investigation, two practitioners of comparative medicine, with an extensive hospital practice, were consulted as to the frequency of this disease in animals. All animals under their care suffered from it more or less, but 80 per cent. of dogs over 8 years of age had the

The results of a detailed neutron scattering study of the temperature dependence of S(Q, ?) for liquid 4He at 20 bars are presented. As was observed in an earlier study at saturated vapour pressure (SVP), it is found that there is a qualitative change in the character of S(Q, ?) on passing through T?and that one-phonon excitations are unique to the superfluid phase. The results are analysed in terms of the Woods-Svensson model, which does not give as good a description as at SVP, and one-phonon intensities, frequencies and intrinsic widths are extracted.

TO THE EDITOR OF THE JOURNAL OF THE AMERICAN MEDICAL ASSOCIATION: I would like to present to the profession through the columns of the Journal an exceedingly interesting case of mal-assimilation of the phosphates and carbonates.The patient is 13 years of age, of very nervous temperament, and has incontinence of urine. At home she is constantly doing things that she ought not to do. She goes to school and learns her lessons apparently without much effort. She eats and sleeps well, partaking largely of meat, but does not care for milk.The condition of her mouth is as follows, and seems to the writer to offer a solution of the trouble: The teeth were covered completely by tartar, and the enamel was easily scraped off. When the tartar was removed the little girl seemed to be in great agony. The teeth would ache, sometimes in one tooth and sometimes