Self-reported stressors, symptom complaints and psychobiological functioning-II: Psychoneuroendocrine variables

Hydroxamate siderophores of virulent Bordetella pertussis and Bordetella bronchiseptica strains were purified using a simple large-scale isolation procedure, and identified by various spectroscopic techniques as the macrocyclic dihydroxamate siderophore trivially known as alcaligin, 1,8(S),11,18(S)- tetrahydroxy-1,6,11,16-tetraazacycloeicosane-2,5,12,15-tetrone+ ++, which was previously isolated from the taxonomically-related bacterial species Alcaligenes denitrificans subsp. xylosoxydans. Alcaligin purified from iron-depleted cultures of B. pertussis and B. bronchiseptica exhibited specific growth-promoting activity under iron-restricted conditions for Bordetella indicator strains, and ere active in [55Fe]ferric alcaligin transport assays. Evidence suggests that several C2-symmetric conformations of alcaligin exist simultaneously in both methanolic and aqueous solution.     

Adenocarcinoma arising in "J" pouch after total proctocolectomy for familial polyposis coli

Cigarette smoking has a major impact both on oral health and general systemic health. Because up to 70 percent of smokers see their dentists each year, the dentist is in a very powerful position to intervene with the smokers to help them stop smoking. I have suggested a four-step program for assisting patients to quit, based on the National Cancer Institute's suggested protocol for the dental office, which uses techniques shown in clinical trials to be effective for helping smokers quit. The core of the NCI program involves identifying smokers, advising them to quit, providing assistance to patients trying to quit, and following-up on patients as a means of enhancing success rates. Dentists who implement an effective smoking cessation program in their practices can expect to achieve quit rates up to 10 to 15 percent each year among their patients who smoke. Such a rate of success, if established nationwide and continued over a period of years, would markedly reduce the prevalence of smoking in the United States.     

Lack of immunosuppressive effect of low-dose oral methotrexate on lymphocytes in rheumatoid arthritis

Whether methotrexate (MTX) is effective in rheumatoid arthritis (RA) because of immunosuppressive and/or anti-inflammatory mechanisms of action is controversial. Many lines of investigation point to the latter. We evaluated DNA synthesis in peripheral blood lymphocytes (PBL) from 33 RA patients on oral MTX (7.5-15 mg/wk) and in 30 healthy controls by flow cytometric cell cycle analysis (CCA). DNA synthesis was also evaluated with a thymidilate synthetase activity assay (TSA) (3H-deoxyuridine incorporation) in 12 patients and 21 controls (12 on MTX and NSAID, and 9 healthy subjects). The patients had taken MTX for at least 3 months and were in different stages of clinical activity. There were no significant differences in TSA or in the cell cycle phase distributions (especially the S phase) between treated RA patients and controls. These data suggest that low-dose oral MTX does not inhibit DNA synthesis and therefore does not have an immunosuppressive effect on lymphocytes from patients with RA.     

Rapid inactivation of prostaglandin endoperoxide synthases by N-(carboxyalkyl)maleimides

N-(Carboxyalkyl)maleimides were synthesized as potential inhibitors of prostaglandin endoperoxide synthase (PGHS). Inactivation of the cyclooxygenase and peroxidase activities of PGHS occurred in a biphasic manner with extremely rapid inactivation followed by slow, time-dependent inactivation. The carboxylic acid moiety was required for rapid inactivation. Optimal inhibition was observed with N-(carboxyheptyl)maleimide, which inhibited the cyclooxygenase activity of ovine PGHS-1 with an IC50 of 0.1 microM and the peroxidase activity with an IC50 of 3 microM. Inactivation of peroxidase activity was not prevented by pretreating the enzyme with the cyclooxygenase inhibitor indomethacin. N-(Carboxyheptyl)-succinimide inhibited neither enzyme activity, suggesting that covalent modification is critical for rapid as well as time-dependent inactivation. Shortening or increasing the alkyl chain by one methylene unit drastically reduced inhibitory potency. N-(Carboxyalkyl)maleimides also instantaneously inactivated the inducible form of PGHS (PGHS-2) from mouse and human sources but with higher IC50's (4.5 and 14 microM, respectively). N-(Carboxyheptyl)maleimide is the most potent covalent inactivator of PGHS yet described with an inhibitory potency 3-5 orders of magnitude greater than aspirin.     

Xanthones from Hypericum japonicum and H. henryi

From the aerial part of Hypericum japonicum, one new xanthone glycoside, 1,5-dihydroxyxanthone-6-O-beta-D-glucoside, one novel dimer xanthone, bijaponicaxanthone, and the first natural prenylated xanthone, 1,3,5,6-tetrahydroxy-4-prenylxanthone, were isolated together with the four known xanthones, 1,5,6-trihydroxyxanthone, isojacereubin, 6-deoxyisojacareubin and 4',5'-dihydro-1,5,6-trihydroxy-4',4',5'-trimethylfurano (2',3':4,5) xanthone. five previously known xanthones, kielcorin, cadensin, 1,7,-dihydroxyxanthone, 1,5-dihydroxy-4-methoxyxanthone and 1,2,5-trihydroxyxanthone were also found in the dichoromethane extract of the stems and leaves of H. henryi. Their structures were elucidated by spectroscopic and chemical methods. Some of the compounds from H. japonicum were found to exert an interesting coagulant activity in an in vitro test. The chemotaxonomic value of xanthones is discussed briefly.     

Adjusting for missing data due to culling before testing in genetic evaluations of swine

The aim of this study was to evaluate data augmentation in genetic evaluations as a method of adjusting for missing data due to culling of pigs before testing. A stochastic simulation was used to generate 10 yr of data for age at test (AGE) and fat thickness (FAT) in a breeding unit with 100 sows and 15 boars. Culling was performed at random (C-RAND), within litters (C-W/IN) or over litters (C-OVER), by deleting two-thirds of the records from the simulated data sets. The culling variate (CVAR) used had genetic and phenotypic correlations of 1.00, .75, .50, and .25 with AGE [r(CVAR, AGE)], whereas culling was uncorrelated with AGE in C-RAND. Missing records for AGE were replaced with their expectations (dummy records), based on the phenotypic average of the tested animals and selection intensities applied. With missing records, predictions were seriously biased for AGE in C-W/IN and especially in C-OVER, when r(CVAR, AGE) exceeded .50 and .25, respectively. The ranking of the animals was more affected in C-OVER than in C-W/IN. With dummy records, bias was removed effectively in cases with a high r(CVAR, AGE) in C-W/IN and C-OVER, whereas a larger bias was created in the opposite direction when r(CVAR, AGE) was less than .50 and for C-RAND. In conclusion, this method was beneficial for adjusting missing data owing to culling, when the correlation between CVAR and AGE was .50 or greater.     

An islander with seizures

An audit of 690 cases of tuberculosis out of 46,276 patients seen during the last 25 years in a busy general practice is reported. Of the 690 cases, 67% were pulmonary, 33% extra-pulmonary TB. Modes of both types of tuberculosis are described and the reason for increased incidence of extra-pulmonary tuberculosis are discussed.