Bioelectrochemical monitoring of phenols and aromatic amines in flow injection using novel plant peroxidases

An amperometric flow system combined with a glucose oxidase-mutarotase reactor was optimized and used to determine aromatic amines and phenols using peroxidase-modified graphite electrodes. An increase in currents upon injection of the analyzed substrate was shown to be approximated by a Michaelis-Menten type dependence. The detection limit was calculated as 3 times the noise, and the sensitivity was calculated as Imax/K(m)app. Commercially available horseradish peroxidase was compared with tobacco anionic and peanut cationic peroxidases for determination of aromatic amines and phenols. Detection limits of 10 nM for determination of o-aminophenol and o- and p-phenylenediamine achieved with a tobacco peroxidase-modified electrode give a promise for further improvements in sensitivities and detection limits of biosensors.     

Molecular characterization of the mycobacterial heparin-binding hemagglutinin, a mycobacterial adhesin

Although it generally is accepted that the interaction of Mycobacterium tuberculosis with alveolar macrophages is a key step in the pathogenesis of tuberculosis, interactions with other cell types, especially epithelial cells, also may be important. In this study we describe the molecular characterization of a mycobacterial heparin-binding hemagglutinin (HBHA), a protein that functions as an adhesin for epithelial cells. The structural gene was cloned from M. tuberculosis and bacillus Calmette-Guérin, and the sequence was found to be identical between the two species. The calculated Mr was smaller than the observed Mr when analyzed by SDS/PAGE. This difference can be attributed to the Lys/Pro-rich repeats that occur at the C-terminal end of the protein and to a putative carbohydrate moiety. Glycosylation of HBHA appears to protect the protein from proteolytic degradation, which results in the removal of the C-terminal Lys/Pro-rich region responsible for binding of HBHA to sulfated carbohydrates. Evidence suggests that glycosylation is also important for HBHA-mediated hemagglutination and for certain immunologic properties of the protein. Finally, the absence of a signal peptide in the coding region of HBHA raises the possibility that this protein is not secreted via the general secretion pathway.     

Reduced interferon gamma production and soluble CD14 levels in early life predict recurrent wheezing by 1 year of age

It is unknown whether reduced production of IFNgamma in early life, before any lower respiratory tract illness, is a risk factor for recurrent wheezing in infancy. We followed 238 infants prospectively from birth to 1 year of age. At birth and at 3 months of age, IFNgamma production from polyclonally stimulated peripheral blood mononuclear cells and soluble CD14 (sCD14) levels in plasma were measured. The odds of developing recurrent wheezing (assessed by questionnaire) in the first year of life were up to 4.5 times higher for children in the lowest quartile of IFNgamma production at 3 months (p = 0.0005) and 3.2 times higher for children in the lowest quartile of sCD14 levels at birth (p = 0.004) as compared with children in the other 3 combined quartiles of IFNgamma and sCD14, respectively. Findings were confirmed in the multivariate analysis. IFNgamma production at 3 months and sCD14 levels at birth were correlated (r = 0.188, p = 0.031). Our findings from a longitudinal cohort suggest that impaired IFNgamma production at 3 months and reduced plasma-sCD14 levels at birth significantly increase the risk of developing recurrent wheezing in the first year of life.     

DNA fingerprinting of the lizard Lacerta dahli: isolation of a genomic polymorphism of mini- and microsatellite loci

We performed a lateral approach for the release of post-traumatic stiffness of the elbow in 22 patients using a modified technique designed to spare the lateral ligaments. They were reviewed after a mean interval of 26 months. The total humeroulnar joint movement had increased from a mean of 74 degrees to 129 degrees and forearm rotation from a mean of 135 degrees to 159 degrees. Both pain and function in the elbow had improved significantly. This modified lateral approach allows release of post-traumatic contracture without disruption of the lateral collateral ligament or the origins of the extensor tendon at the lateral epicondyle of the humerus. The advantages include a simplified surgical procedure, less operative morbidity, and unrestricted rehabilitation.     

The relationship between cholecystectomy, unoperated gallstone disease, and colorectal cancer. A necropsy study

BACKGROUND: There may be an increased risk of colorectal cancer after cholecystectomy, but the literature is not consistent. It is also possible that any risk might be associated with gallstones rather than cholecystectomy. METHODS: In a prospective necropsy study of 8563 cases, all 219 cases of a previous cholecystectomy were pair-matched to subjects with gallstones and to subjects with a normal gallbladder. In a second study all 192 cases of colorectal cancer were pair-matched to cancer-free subjects. RESULTS: The odds ratio (OR) for developing colorectal cancer after cholecystectomy compared with a normal gallbladder was 1.0 (95% confidence interval, 0.30-3.34) and with unoperated gallstones was 0.88 (0.27-2.76). CONCLUSIONS: This study fails to support an association between cholecystectomy or gallstones and colorectal cancer. For those cases of colorectal cancer versus controls, the OR for previous cholecystectomy was 0.70 (0.23-2.04) and for gallstone disease was 0.93 (0.58-1.48).     

Acute and long-term outcomes of extremely injured blunt trauma victims

Long-term outcomes after blunt trauma remain poorly defined. The purpose of this study was to document such outcomes in extremely injured adults (Injury Severity Score > or = 50). From April 1990 to June 1993, 76 patients (5% of all trauma victims) had an ISS > or = 50 at a single trauma center. Thirty-five (46%) survived to hospital discharge. The mean duration of hospital stay was longer for survivors than for nonsurvivors (92 days versus 16 days, p < 0.001). Of the 35 survivors, 26% were discharged directly home, 60% to a rehabilitation hospital, 8% to a chronic care facility, and 6% to an acute care hospital. After a mean follow-up of 27 months, 6% had died, 9% refused participation, and the remaining 30 patients (91% of long-term survivors) demonstrated significant residual disabilities in physical, emotional, and mental health status. We suggest that extremely injured patients comprise a small proportion of blunt trauma victims, consume substantial acute care hospital resources, often survive, and yet frequently have residual disability. A reduction in this long-term disability may represent the greatest challenge in modern trauma care.     

Human trophoblast interferons: production and possible roles in early pregnancy

Human villous and extravillous trophoblast populations were isolated from first- and third-trimester placentae and were stimulated with viral and non-viral inducers to produce interferons (IFNs). Polyriboinosinic/polyribocytidylic acid [poly(I:C)] induced exclusively IFN-beta in trophoblast cultures, whereas viruses induced mixtures of IFN-alpha subtypes and -beta. The level of IFN production was dependent on the trophoblast population, type of inducer and the stage of differentiation of the trophoblast. First-trimester extravillous trophoblast cultures produced greater than five-fold more IFN than third-trimester villous trophoblast on a per cell basis, whereas term syncytiotrophoblast produced twice as much IFN as term mononuclear villous trophoblast when stimulated with the same inducer. Pretreatment of trophoblast cultures with platelet-derived growth factor and granulocyte/macrophage-colony stimulating factor (GM-CSF) increased the trophoblast IFN production. Tandem high-performance affinity chromatography of the virus-induced trophoblast IFNs resulted in the isolation of trophoblast IFN-alpha and -beta with specific antiviral activities of 0.75-2.73 x 10(8) IU/ml protein. The trophoblast-induced IFNs have antiproliferative and immunosuppressive properties, and, furthermore, activated natural killer cell activity. These data may suggest the possible roles of these IFNs during embryonic development with regard to protection of the fetus against viral infection and maternal immunity.     

Influence of light dark cycles on estradiol-17 beta induced luteinizing hormone patterns of the prepuberal gilt

Two groups of Yorkshire gilts (110 d of age) were maintained in two light regimens. Both light regimens consisted of 14 h of light and 10 h of darkness, but were 180 degrees out of phase. Gilts in Group 1 received light from 1200 to 0200 and gilts in Group 2 from 2400 to 1400. At approximately 140 d of age each group was divided into four subgroups of eight gilts each (1A, 1B, 1C, 1D or 2A, 2B, 2C, 2D). All gilts were blood sampled at 2-h intervals for 5 d commencing on d 142. The four subgroups received a single injection of estradiol (15 micrograms/kg body weight) on d 143 at either 2400 (A), 0600 (B), 1200 (C), or 1800 (D). For pigs in Groups 1A and 1D, the injection of estradiol coincided with the animals' "subjective day" and the injections given to Groups 1B and 1C with their "subjective night." When estradiol-17 beta (E2) was administered to the gilts during their subjective day the LH profile showed one peak, whereas when E2 was administered during dark hours the profile exhibited two peaks (P < .0001). In Group 2 for which the light cycle was reversed, the well-defined spikes of LH were found to coincide with the injections of estradiol administered during the dark hours. Smaller biphasic peaks of LH occurred when injections of estradiol coincided with the light hours.(ABSTRACT TRUNCATED AT 250 WORDS)