Periodontal disease in the prehistoric Ipiutak and Tigara skeletal remains from Point Hope,Alaska

Two large groups of prehistoric Eskimo skeletons from Point Hope, Alaska, were evaluated for dental wear and several measures of periodontal disease. Occlusal attrition was found to increase steadily with increasing age. Crown height decreased proportionately. Assessing periodontal disease by inspecting apparent alveolar recession was judged ineffective due to possible supereruption. Infrabony pockets, the result of severe localized periodontal disease indicated that in Ipiutak people between the ages of 25 and 30, and Tigara people between 35 and 40, more dental sites were affected by periodontal disease than were not. This suggests a cultural, genetic, or dietary difference between the two groups. Male/female differences were slight in all parameters studied.     

Sulfur-containing cyclic ketimines and imino acids. A novel family of endogenous products in the search for a role.

Aminoethylcysteine, lanthionine, cystathionine and cystine are mono-deaminated either by L-amino-acid oxidase or by a transaminase exhibiting the properties described for glutamine transaminase. The deaminated products cyclize producing the respective ketimines. Authentic samples of each ketimine were prepared by reacting the appropriate aminothiol compound with bromopyruvate, except cystine ketimine which required the interaction of thiopyruvate with cystine sulfoxide. Reduction of the first three mentioned ketimines with NaBH4 yields the respective derivatives with the saturated rings of thiomorpholine and hexahydrothiazepine. The same reduction is carried out enzymically by a reductase extracted from mammalian tissues. Properties of the members of this family of compounds are described. Gas chromatography followed by mass spectrometry permits the identification of most of these products. HPLC is very useful for the determination of the ketimines by taking advantage of specific absorbance at 380 nm obtained by prior derivatization with phenylisothiocyanate. Adaptation of these and other analytical procedures to biological samples disclosed the presence of most of these compounds in bovine brain and in human urine. By using [35S]lanthionine ketimine as a representative member of the ketimine group, the specific, high-affinity, saturable and reversible binding to bovine brain membranes has been demonstrated. The binding is removed by aminoethylcysteine ketimine and by cystathionine ketimine indicating the occurrence in bovine brain of a common binding site for ketimines. The reduced ketimines are totally ineffective in competing with [35S]lanthionine ketimine. Alltogether these findings are highly indicative for the existence in mammals of a novel class of endogenous sulfur-containing cyclic products provided with a possible neurochemical function to be investigated further.     

The effect of feeding on plasma immunoreactive ACTH and beta-endorphin levels in newborn infant.

In order to clarify whether an interaction between endogenous opioids and feeding occurs at birth, we studied Beta-endorphin (beta-EP) and ACTH plasma levels in response to a feed of 10% glucose, or formula, in 120 healthy full-term infants. Neither postprandial beta-EP nor ACTH increases were found at the 24th hour or on the fourth day of life. beta-EP physiology in newborn infants seems to be different from adults.     

Inhibition of Sucrose Enhancer Effect of the Potato Proteinase Inhibitor II Promoter by Salicylic Acid

Effect of salicylic acid (SA) on the expression of the potato proteinase inhibitor (PI) II promoter was studied with transgenic tobacco plants (Nicotiana tabacum) carrying a gene fusion between the PI-II promoter and the chloramphenicol acetyltransferase (cat) reporter. As previously observed, the PI-II promoter was inducible by wounding and the promoter activity was further enhanced by sucrose. Addition of SA did not influence the wound induction of the PI-II promoter but significantly inhibited the sucrose response. The 5′-deletion mutant −573 was unable to respond to wounding but did respond to sucrose and SA. The 3′-deletion analysis indicated the presence of a sucrose-responsive element between −574 and −520. A study of the insertion mutants revealed the function of another sucrose-responsive element between −522 and −500. Enhancer effects of these sucrose-responsive elements were inhibited by SA. These studies suggest that SA inhibits PI-II promoter activity by decreasing the sucrose response. Analysis of SA-related chemicals revealed that only acetyl-SA showed a similar inhibitory effect, and other hydroxybenzoic acids had little or no effect on the sucrose enhancer activity. Therefore, it seems that the interaction between SA and the receptor molecule is specific.     

Subclinical psoroptic otocariasis in Brazilian sheep with comments on a technique for mite collection

Subclinical psoroptic otocariasis associated withPsoroptes cuniculi (Delafond) was diagnosed in four out of ten herds of sheep. Transmission of mites between sheep and goats and vice versa was detected in herds kept on the same pastures for over 2 years. Flushing the ear canals of sheep and goats with approximately 50 ml of water appreared to be more efficient than swabbing or otoscopic examination for diagnosis and/or mite collection.     

Cervicovaginal cytology in uterine adenocarcinoma and adenosquamous carcinoma. Comparison of cytologic and histologic findings

To investigate the diagnostic accuracy and to characterize the findings in false-negative cases, the results of cervicovaginal cytology in 56 adenocarcinomas and 25 adenosquamous carcinomas (42 cervical, 36 endometrial, 2 metastatic and 1 arising synchronously from both cervix and endometrium) were reviewed, including review of the actual slides in 56 cases. Overall, 80% of the initial cytologic diagnoses resulted in diagnostic curettage (i.e., cytology was effectively positive); 84% of the postreview diagnosis were effectively positive. Nine cytology slides showed no malignant cells; eight of these negative smears showed repair, five were atrophic, two showed a high estrogen effect and one had enlarged atypical bare nuclei. These false-negative diagnoses were associated with an endometrial primary site (P less than .01), endometrioid histology (P less than .005), low-grade or intermediate-grade histology (P less than .005), small size of tumor (P less than .05) and absence of cervical involvement (P less than .005) in those cases in which a hysterectomy was performed. False-negative diagnoses were not associated with an absence of endocervical cells or with scanty cellularity. Of 39 cervical and 28 endometrial carcinomas with a positive cytologic diagnosis (initially or after review of the available slides), cytology correctly identified the primary site in 18% and 54% of the cases, respectively. Cytology incorrectly classified the anatomic site of four cervical and three endometrial carcinomas and considered one case arising in both the endometrium and cervix to be endometrial. Routine cervicovaginal cytology does have a role in screening for uterine glandular carcinoma; to maximize its diagnostic sensitivity, we suggest using a recommendation for curettage in the report of positive cases so that all of the varied cytologic diagnoses associated with glandular carcinomas will receive a uniform clinical response. In those cases with preserved cancer cells, a correlation can be made with the histologic type of the carcinoma, rather than with the anatomic site.     

Gastrulation in Drosophila: the formation of the ventral furrow and posterior midgut invaginations

The ventral furrow and posterior midgut invaginations bring mesodermal and endodermal precursor cells into the interior of the Drosophila embryo during gastrulation. Both invaginations proceed through a similar sequence of rapid cell shape changes, which include apical flattening, constriction of the apical diameter, cell elongation and subsequent shortening. Based on the time course of apical constriction in the ventral furrow and posterior midgut, we identify two phases in this process: first, a slow stochastic phase in which some individual cells begin to constrict and, second, a rapid phase in which the remaining unconstricted cells constrict. Mutations in the concertina or folded gastrulation genes appear to block the transition to the second phase in both the ventral furrow and the posterior midgut invaginations.     

Hexaheme nitrite reductase from Desulfovibrio desulfuricans. M?ssbauer and EPR characterization of the heme groups

M?ssbauer and EPR spectroscopy were used to characterize the heme prosthetic groups of the nitrite reductase isolated from Desulfovibrio desulfuricans (ATCC 27774), which is a membrane-bound multiheme cytochrome capable of catalyzing the 6-electron reduction of nitrite to ammonia. At pH 7.6, the as-isolated enzyme exhibited a complex EPR spectrum consisting of a low-spin ferric heme signal at g = 2.96, 2.28, and 1.50 plus several broad resonances indicative of spin-spin interactions among the heme groups. EPR redox titration studies revealed yet another low-spin ferric heme signal at g = 3.2 and 2.14 (the third g value was undetected) and the presence of a high-spin ferric heme. M?ssbauer measurements demonstrated further that this enzyme contained six distinct heme groups: one high-spin (S = 5/2) and five low-spin (S = 1/2) ferric hemes. Characteristic hyperfine parameters for all six hemes were obtained through a detailed analysis of the M?ssbauer spectra. D. desulfuricans nitrite reductase can be reduced by chemical reductants, such as dithionite or reduced methyl viologen, or by hydrogenase under hydrogen atmosphere. Addition of nitrite to the fully reduced enzyme reoxidized all five low-spin hemes to their ferric states. The high-spin heme, however, was found to complex NO, suggesting that the high-spin heme could be the substrate binding site and that NO could be an intermediate present in an enzyme-bound form.     

Arabitol accumulation in Geotrichum candidum

Culture conditions which lead to the intracellular accumulation of arabitol and mannitol in Geotrichum candidum were investigated. The accumulation of arabitol was dependent on the concentrations of metabolizable hexoses, the non-metabolizable disaccharide sucrose, NaCl and KCl in the growth medium. In media containing 2% (w/v) glucose, fructose or l-sorbose cultures contained only mannitol after 48 h or 72 h growth. In media containing 10% (w/v) to 30% (w/v) glucose, or 25% (w/v) fructose or l-sorbose there was an increase in the total concentration of intracellular polyol due to the accumulation of arabitol. This pentitol was also found to accumulate intracellularly when the organism was grown in medium containing 34% (w/v) sucrose, 0.7 M NaCl or 0.7 M KCl in addition to 2% (w/v) glucose. Under the conditions tested no change in the accumulation of mannitol or ethanol-soluble carbohydrate, believed to be primarily composed of trehalose, was evident.Intracellular polyol was released during incubation of arthrospores obtained from media containing 25% or 10% glucose, in distilled water at 25° C, but no polyol was released under these conditions from arthrospores obtained from growth in 2% glucose medium.