Toluene degradation in the recycle liquid of biotrickling filters for air pollution control

Pollutant degradation in biotrickling filters for waste air treatment is generally thought to occur only in the biofilm. In two experiments with toluene degrading biotrickling filters, we show that suspended microorganisms in the recycle liquid may substantially contribute to the overall pollutant removal. Two days after reactor start up, the overall toluene elimination capacity reached a maximum of 125 g m(-3) h(-1), which was twice that found during prolonged operation. High biodegradation activity in the recycle liquid fully accounted for this short-term peak of pollutant elimination. During steady-state operation, the toluene degradation in the recycle liquid was 21% of the overall elimination capacity, although the amount of suspended biomass was only 1% of the amount of immobilized biomass. The results suggest that biotrickling filter performance may be improved by selecting operating conditions allowing for the development of an actively growing suspended culture.

Increase of GAP-43 expression following kainic acid injection into whisker barrel cortex

Plasticity after microinjection of kainic acid (KA) into the adult rat whisker barrel cortex was investigated with immunohistochemical staining of phosphorylated growth-associated protein (GAP)-43. After mapping the barrel cortex with the technique of intrinsic signal optical imaging, a small volume of KA was injected into one barrel. Rats were sacrificed at 2 days, 3 days, 1 week, and 6 weeks after lesioning. GAP-43 staining demonstrated intense immunoreactivity (IR) at the injected barrel which spread to the inter-barrel septa and the surrounding barrels. Elevated IR of GAP-43 was visible 2 days after KA injection, and increased gradually at least 6 weeks following the lesion. This model has the possibility of offering a simple and reliable tool for studying cortical plasticity.

Difference in incidence of spontaneous mutations between Herpes simplex virus types 1 and 2

Spontaneous mutations within the herpes simplex virus (HSV) genome are introduced by errors during DNA replication. Indicative of the inherent mutation rate of HSV DNA replication, heterogeneous HSV populations containing both acyclovir (ACV)-resistant and ACV-sensitive viruses occur naturally in both clinical isolates and laboratory stocks. Wild-type, laboratory-adapted HSV type 1 (HSV-1) strains KOS and Cl101 reportedly accumulate spontaneous ACV-resistant mutations at a frequency of approximately six to eight mutants per 10(4) plaque-forming viruses (U. B. Dasgupta and W. C. Summers, Proc. Natl. Acad. Sci. USA 75:2378-2381, 1978; J. D. Hall, D. M. Coen, B. L. Fisher, M. Weisslitz, S. Randall, R. E. Almy, P. T. Gelep, and P. A. Schaffer, Virology 132:26-37, 1984). Typically, these resistance mutations map to the thymidine kinase (TK) gene and render the virus TK deficient. To examine this process more closely, a plating efficiency assay was used to determine whether the frequencies of naturally occurring mutations in populations of the laboratory strains HSV-1 SC16, HSV-2 SB5, and HSV-2 333 grown in MRC-5 cells were similar when scored for resistance to penciclovir (PCV) and ACV. Our results indicate that (i) HSV mutants resistant to PCV and those resistant to ACV accumulate at approximately equal frequencies during replication in cell culture, (ii) the spontaneous mutation frequency for the HSV-1 strain SC16 is similar to that previously reported for HSV-1 laboratory strains KOS and Cl101, and (iii) spontaneous mutations in the laboratory HSV-2 strains examined were 9- to 16-fold more frequent than those in the HSV-1 strain SC16. These observations were confirmed and extended for a group of eight clinical isolates in which the HSV-2 mutation frequency was approximately 30 times higher than that for HSV-1 isolates. In conclusion, our results indicate that the frequencies of naturally occurring, or spontaneous, HSV mutants resistant to PCV and those resistant to ACV are similar. However, HSV-2 strains may have a greater propensity to generate drug-resistant mutants than do HSV-1 strains.

Associations between uncoupling protein 2, body composition, and resting energy expenditure in lean and obese African American, white, and Asian children

BACKGROUND

Little is known about genes that affect childhood body weight.

OBJECTIVE

The objective of this study was to examine the association between alleles of the mitochondrial uncoupling protein 2 (UCP2) gene and obesity because UCP2 may influence energy expenditure.

DESIGN

We related UCP2 genotype to body composition and resting energy expenditure in 105 children aged 6-10 y. Overweight children and nonoverweight children of overweight parents were genotyped for a 45-base pair deletion/insertion (del/ins) in 3'-untranslated region of exon 8 and for an exon 4 C to T transition.

RESULTS

Eighty-nine children were genotyped for the exon 8 allele: 50 children had del/del, 33 had del/ins, and 6 had ins/ins. Mean (+/-SD) body mass index (BMI; in kg/m(2)) was greater for children with del/ins (24.1 +/- 5.9) than for children with del/del (20.4 +/- 4.8; P < 0.001). BMI of ins/ins children (23.7 +/- 7.8) was not significantly different from that of del/ins children. A greater BMI in del/ins children was independent of race and sex. Body composition was also different according to UCP2 genotype. All body circumferences and skinfold thicknesses examined were significantly greater in del/ins than in del/del children. Body fat mass as determined by dual-energy X-ray absorptiometry was also greater in del/ins than in del/del children (P < 0.005). For 104 children genotyped at exon 4, no significant differences in BMI or body composition were found among the 3 exon 4 genotypes. Neither resting energy expenditure nor respiratory quotient were different according to UCP2 exon 4 or exon 8 genotype.

CONCLUSIONS

The exon 8 ins/del polymorphism of UCP2 appears to be associated with childhood-onset obesity. The UCP2/UCP3 genetic locus may play a role in childhood body weight.

Analysis of cyclin-dependent kinase inhibitor expression and methylation patterns in human prostate cancers

BACKGROUND

Downregulation of genes which negatively control cell cycle progression represents a possible mechanism for prostate tumorigenesis. We examined the expression levels of the p16, p15, p14, and retinoblastoma-susceptibility (RB) genes in primary prostate cancers and human prostate cancer cell lines, and correlated this with the DNA methylation levels of two loci in p16.

METHODS

The mRNA levels of p16, p15, and p14 were examined by reverse transcriptase-PCR (RT-PCR). DNA methylation of the p16 5' CpG island was determined by bisulfite genomic sequencing, while methylation of exon 2 shared by the p16 and p14 genes was measured by a quantitative bisulfite-based technique, methylation-sensitive single-nucleotide primer extension (Ms-SNuPE). RB protein levels were assessed by immunohistochemical staining of histologic sections of normal and tumor prostate tissues, using a monoclonal antibody (mAB).

RESULTS

Overexpression of p16 mRNA was found in 6/9 (67) of prostate tumors compared to the adjacent normal prostate, whereas elevated p14 and p15 levels were only observed in 2/9 (22) and 1/6 (17) of prostate cases, respectively. There was no statistically significant association of grade (P = 0.18) and stage (P = 1.00) of prostate cancer to the elevated p16 levels in the tumors. The p16 5' CpG island was completely unmethylated in these tissues. In contrast, exon 2 of p16/p14 was methylated in both the tumor and normal adjacent prostates, and was increased in 8/11 (73) of tumors relative to normal tissues. There was no association between p16 overexpression and increased p16/p14 exon 2 methylation in these tumors (P = 1.00). Diminished RB levels in prostate tumors that had upregulated p16 mRNA were found, although absent RB was also detected in tumors without elevated p16 levels. The expression levels of the two genes, RB and p16, were not correlated statistically (P = 0.16).

CONCLUSIONS

Our studies show that although the levels of the cell cycle regulators p16, p15, p14, and Rb are altered in prostate cancers, there is no apparent correlation to grade, stage, or any pattern of regulation between the related genes. Exon 2 of p16/p14 is methylated in a majority of prostate tumors compared to the unmethylated upstream 5' region, and may be a potential tumor marker for human prostate cancer.

The epidemiology of typhoid fever in the Dong Thap Province, Mekong Delta region of Vietnam

A population-based surveillance for typhoid fever was conducted in three rural communes of Dong Thap Province in southern Vietnam (population 28,329) for a 12-month-period starting on December 4, 1995. Cases of typhoid fever were detected by obtaining blood for culture from residents with fever > or = 3 days. Among 658 blood cultures, 56 (8.5%) were positive for Salmonella typhi with an overall incidence of 198 per 10(5) population per year. The peak occurrence was at the end of the dry season in March and April. The attack rate was highest among 5-9 year-olds (531/10(5)/year), and lowest in > 30 year-olds (39/10(5)/year). The attack rate was 358/10(5)/year in 2-4 year-olds. The isolation of S. typhi from blood cultures was highest (17.4%) in patients with 5 to 6 days of fever. Typhoid fever is highly endemic in Vietnam and is a significant disease in both preschool and school-aged children.

Quantitative measure of c-abl and p15 methylation in chronic myelogenous leukemia: biological implications

We used a sensitive, quantitative bisulfite PCR assay, methylation sensitive single nucleotide primer extension (Ms-SNuPE), to measure methylation of the 5' CpG islands of c-abl and p15 in chronic myelogenous leukemia (CML) patients during progression. We found that the Pa promoter of c-abl was methylated in 81% (17/21) of the white blood cells (WBCs) of CML patients, which correlates with previous reports. In contrast, WBCs from healthy donors, acute myelogenous leukemias, acute lymphocytic leukemias, and myelodysplastic syndromes were unmethylated at the c-abl Pa promoter locus. We also observed p15 hypermethylation in 24% (8/34) of CML cases. Methylation of the p15 but not c-abl Pa promoters was associated with CML progression (P = 0.047 vs 0.46), and the two events were independently acquired. We conclude that de novo methylation of c-abl and p15 both occur in CML, and analysis of DNA methylation changes using the bisulfite-based MS-SNuPE assay allows both a sensitive and quantitative assessment of these molecular events compared to other methods currently utilized. (Blood. 2000;95:2990-2992)

Two critical cysteine residues implicated in disulfide bond formation and proper folding of Kir2.1

Inwardly rectifying potassium channels are important in cellular repolarization of many excitable tissues. Amino acid sequence alignment of different mammalian inward rectifier K(+) channels revealed two absolutely conserved cysteine residues in the putative extracellular face, suggesting a possible disulfide bond. Replacement of these cysteine residues in the Kir2.1 channel (i.e., C122 and C154) with either alanine or serine abolished current in Xenopus laevis oocytes although Western blotting established that the channels were fully expressed. The digestion pattern of channels treated with V8 protease combined with Western blotting under reducing and nonreducing conditions confirmed intrasubunit cross-linking of C122 and C154. Whole-cell and single channel current recordings of oocytes expressing tandem tetrameric constructs with one or two of the mutant subunits suggested that insertion of one mutant subunit is sufficient to eliminate channel function. Coexpression studies confirmed that the cysteine mutant channels eliminate wild-type Kir2.1 currents in a dominant-negative manner. Despite these results, sulfhydryl reduction did not alter the functional properties of Kir2.1 currents. Molecular modeling of Kir2.1 with the two cysteines cross-linked predicted that the extracellular loop between the first transmembrane domain and the pore helix contains a beta-hairpin structure. Distinct from the KcsA structure, the disulfide bond together with the beta-hairpin structure is expected to constrain and stabilize the P-loop and selectivity filter. Taken together, these results suggest that intramolecular disulfide bond exists between C122 and C154 of Kir2.1 channel and this cross-link might be required for proper channel folding.

A prospective study of holiday weight gain

BACKGROUND

It is commonly asserted that the average American gains 5 lb (2.3 kg) or more over the holiday period between Thanksgiving and New Year's Day, yet few data support this statement.

METHODS

To estimate actual holiday-related weight variation, we measured body weight in a convenience sample of 195 adults. The subjects were weighed four times at intervals of six to eight weeks, so that weight change was determined for three periods: preholiday (from late September or early October to mid-November), holiday (from mid-November to early or mid-January), and postholiday (from early or mid-January to late February or early March). A final measurement of body weight was obtained in 165 subjects the following September or October. Data on other vital signs and self-reported health measures were obtained from the patients in order to mask the main outcome of interest.

RESULTS

The mean (+/-SD) weight increased significantly during the holiday period (gain, 0.37+/-1.52 kg; P<0.001), but not during the preholiday period (gain, 0.18+/-1.49 kg; P=0.09) or the postholiday period (loss, 0.07+/-1.14 kg; P=0.36). As compared with their weight in late September or early October, the study subjects had an average net weight gain of 0.48+/-2.22 kg in late February or March (P=0.003). Between February or March and the next September or early October, there was no significant additional change in weight (gain, 0.21 kg+/-2.3 kg; P=0.13) for the 165 participants who returned for follow-up.

CONCLUSIONS

The average holiday weight gain is less than commonly asserted. Since this gain is not reversed during the spring or summer months, the net 0.48-kg weight gain in the fall and winter probably contributes to the increase in body weight that frequently occurs during adulthood.

Ammonia toxicity as a criterion for the evaluation of larval quality in the prawn Macrobrachium rosenbergii

The feasibility of a short-term ammonia toxicity test as an evaluation criterion for larval quality was assessed in three trials. In each one, Macrobrachium rosenbergii larvae originating from the same spawn were nutritionally differentiated in two groups by feeding them either a nutrient-rich (Artemia nauplii enriched for 24 h with n-3 highly unsaturated fatty acids (HUFA) and ascorbic acid (AA)) or a nutrient-poor diet (Artemia nauplii starved for 24 h). Throughout their development, larvae from both treatments were exposed during 24 h to six concentrations of total ammonia (NH(4)(+)+NH(3)) and a control (no ammonia added). Based on mortality rates, the median lethal concentration for 50% of the population (LC(50)) was estimated. As expected from earlier work, larvae fed the optimal diet presented higher n-3 HUFA and AA contents as well as higher growth and metamorphosis rates. From the moment the effect of diet quality was analytically detectable in the tissues of the larvae, the ammonia test was able to distinguish both groups of larvae. Differences in ammonia tolerance were observed as early as larval stage 4 and remained evident throughout larval development. The short-term ammonia toxicity test proved to be a valuable, sensitive and reproducible criterion for the establishment of larval quality.

Negative electrostatic contribution to the bending rigidity of charged membranes and polyelectrolytes screened by multivalent counterions

Bending rigidity of a charged membrane or polyelectrolyte screened by monovalent counterions is known to be enhanced by electrostatic effects. We show that in the case of screening by multivalent counterions the electrostatic effects reduce the bending rigidity. This inversion of the sign of the electrostatic contribution is related to the formation of two-dimensional strongly correlated liquids (SCL) of counterions at the charged surface due to strong lateral repulsion between them. When a membrane or a polyelectrolyte is bent, SCL is compressed on one side and stretched on the other so that thermodynamic properties of SCL contribute to the bending rigidity. Thermodynamic properties of SCL are similar to those of Wigner crystal and are anomalous in the sense that the pressure, compressibility and screening radius of SCL are negative. This brings about substantial negative correction to the bending rigidity. For the case of DNA this effect qualitatively agrees with experiment.

Bacteria and mosquito abundance in microcosms enriched with organic matter and treated with a Bacillus thuringiensis subsp. israelensis formulation

Bacteria and mosquito abundance were studied in outdoor tubs unenriched and enriched with 0.04% rabbit pellets during the winter, 1999. The irrigation water used to fill the tubs contained a total bacterial count of 1.15-1.35 x 10(3) cells/ml. Adding rabbit pellets for enrichment yielded a total bacterial count of 5.50-7.63 x 10(5) cells/g. Bacterial densities in unenriched water were significantly lower than in enriched tubs on every sampling day. When bacterial densities in both enriched and unenriched regimens reached peak populations on day 3 post-flooding, their numbers in enriched water were 25-fold higher than the unenriched water. Under cool weather conditions, mosquito oviposition activity was low and larval development was very slow. Egg raft counts and larval densities in enriched water were nevertheless higher than those in unenriched water. After reaching peak populations on day 3 post-flooding, the natural decline in bacterial densities in the top portion of enriched water without mosquito larvae was lower compared with that in water with larvae. In water with larval present, the decline of bacterial levels in top water was greater than in bottom water on day 7 post-flooding. VectoBac G, a granular formulation of Bacillus thuringiensis subsp. israelensis caused a reduction in larval numbers of 80, 93, 73% at the rate of 5.5 lb/ac and a reduction of 94, 93, 86% at the rate of 10.6 lb/ac on days, 1, 3, 7 posttreatment, respectively. After treatment, the reductions of bacterial densities in untreated tubs were greater than treated tubs. These results indicate that mosquito larvae play an important role in the decline of bacterial populations by their feeding activity.

The cholesterol-lowering action of plant stanol esters

Plant sterols and stanols derived from wood pulp and vegetable oils lower total and LDL cholesterol by inhibiting cholesterol absorption from the intestine in humans. Plant stanols are virtually unabsorbable, which makes them more ideal hypocholesterolemic agents than plant sterols. The esterification of plant stanols has allowed their incorporation into various foods such as margarine without changing the taste and texture of those foods. Plant stanol esters at a level of 2-3 g/d have been shown to reduce LDL cholesterol by 10-15% without side effects. Plant stanol esters appear to be a helpful dietary adjunct to a prudent diet to lower cholesterol.

Parental compliance with multiple immunization injections

OBJECTIVE

To assess parents' (or caretakers') willingness to allow multiple immunization injections at a single visit.

DESIGN

A survey of parental demographics and a medical record review to determine immunization status.

SETTING

An inner-city pediatric clinic in Philadelphia, Pa.

PARTICIPANTS

A convenience sample of 1059 patients who were due to receive 2 to 5 immunization injections at a single visit and their parents. Patients were excluded if parents had not previously witnessed at least 1 immunization.

MAIN OUTCOME MEASURES

The number of immunizations due, the number of immunizations received, and the reasons for failure to immunize completely.

RESULTS

Almost all (98.8%) of the children included in the study received all immunizations indicated at their visit.

CONCLUSION

Despite potential parental resistance to multiple simultaneous immunization injections, this innercity population overwhelmingly complied with physicians' recommendations.

Cholesterol-lowering effect of stanol ester in a US population of mildly hypercholesterolemic men and women: a randomized controlled trial

OBJECTIVE

To determine the efficacy of stanol esters in lowering cholesterol in a US population.

SUBJECTS AND METHODS

After a run-in phase, 318 subjects were randomized to receive one of the following margarine-like spreads containing stanol ester or placebo for 8 weeks: EU 3 G: 1 g of stanol (ester form) per 8-g serving of a European formula 3 times a day; US 3 G: 1 g of stanol (ester form) per 8-g serving of a US reformulation 3 times a day; US 2 G: 0.67 g of stanol (ester form) per 8-g serving of a US reformulation 3 times a day; or placebo spread.

RESULTS

Mean +/- SD baseline total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) levels were 233+/-20 and 153+21 mg+/-dL, respectively. In the US 3 G group, 3 g daily of stanol esters lowered TC and LDL-C levels by 6.4% and 10.1%, respectively. There was a dose-dependent response compared with 2 g daily (US 2 G). Triglyceride and high-density lipoprotein cholesterol levels were unchanged. The incidence of adverse effects was not different from placebo. Serum vitamin A and 25-hydroxyvitamin D levels were not affected.

CONCLUSIONS

Stanol esters lowered TC and LDL-C levels in a mildly hypercholesterolemic US population without evidence of adverse effects. It may be a useful dietary adjunct to lower cholesterol.

Mosquito control and bacterial flora in water enriched with organic matter and treated with Bacillus thuringiensis subsp. israelensis and Bacillus sphaericus formulations

Three tests were conducted during July 17 to October 30, 1998 to study the impact of two mosquitocidal microbial agents on mosquito larvae and their contribution to bacterial flora in aquatic microcosms. Formulations of Bacillus thuringiensis subsp. israelensis (Bti) and Bacillus sphaericus strain 2362 (Bsph) were applied at various rates to outdoor tubs enriched with rabbit pellets and filled with irrigation water from a reservoir. Mosquito larvae were effectively controlled by all treatments; the magnitude of initial and persistent control depended on materials and dosages applied. Bacterial flora were assessed in the irrigation water as well as water in the enriched tubs before and after treatment with the microbial agents. The irrigation water contained 800-1000 total bacterial cells/ml. The populations of total bacteria and spore formers peaked on day 3 after enriching and filling the tubs, then declined progressively to the low levels at the end of the tests. After treatment, the numbers of Bti and Bsph spores in treated tubs prevailed at a dosage-dependent manner, their populations peaked at three hours after treatment, and declined progressively thereafter. The contribution of Bti and Bsph spores to the total bacterial flora was negligible but significant to the counts of spore-forming bacteria. The gram-negative bacteria made up more than 80% of the total bacterial flora during the test periods; and, of these, gram-negative rods constituted the greatest proportion, gradually increasing from the time of flooding to the end of the tests. Gram-negative cocci also occurred in relatively great proportion, but showed a reverse trend as compared with the gram-negative rods, declining gradually from pretreatment to the end of the tests. Gram-positive rods (spore formers), including Bti and Bsph, occurred in low numbers in all the tests but increased slightly in treated tubs due to the addition of Bti and Bsph spores. Gram-positive cocci occurred occasionally in some water samples.

Clomiphene-induced severe hypertriglyceridemia and pancreatitis

Clomiphene has been available for clinical use since 1960 and has been successfully used to aid fertility in women with certain anovulatory disorders. It is a synthetic estrogen analog, of the triphenylethylene derivative group, and its biochemical structure is similar to that of tamoxifen. Estrogen and tamoxifen lower total and low-density lipoprotein cholesterol and increase triglyceride and high-density lipoprotein cholesterol levels. In patients with baseline hypertriglyceridemia, these agents can induce severe hypertriglyceridemia and pancreatitis. The actions of clomiphene on lipid metabolism have not been studied, and to our knowledge, no cases of severe hypertriglyceridemia related to the use of clomiphene have been described. We report the case of a woman who developed 2 episodes of clomiphene-induced hypertriglyceridemia and pancreatitis while receiving this drug for treatment of infertility. Given the striking structural similarity between clomiphene and tamoxifen, it is likely that clomiphene is capable of inducing severe hypertriglyceridemia in patients with certain underlying lipid disorders by a mechanism similar to that of tamoxifen.

Changes in metabolism of TRH in euthyroid sick syndrome

OBJECTIVE

The aim of this study was to examine the metabolism of a simple dose, intravenously administered TRH bolus of 200 microg, in patients with euthyroid sick syndrome (ESS).

PATIENTS AND METHODS

A TRH test was performed on ten ESS patients and ten controls upon admission (d1) and after recovery (d2). Blood samples were collected at 0, 10, 20 and 30min after TRH injection. We analyzed the volume of distribution (V(d)), the plasma clearance rate (PCR), the fractional clearance rate (FCR), the half-life (t(1/2)) and the TSH response to the injection of TRH.

RESULTS

All patients had lower tri-iodothyronine (T(3)) levels compared with controls (0.9 +/- 0. 1nmol/l vs 1.9 +/- 0.1 nmol/l; P < 0.0001; mean +/- S.D.; paired t-test). In addition, the V(d) (16.7 +/- 5.9/l vs 30.6 +/- 0.6/l; P < 0.0005) and PCR (2.0 +/- 0.80 l/min vs 3.3 +/- 0.25 l/min; P <0. 0005) were found statistically lowered in patients than in controls, whereas FCR (0.119 +/- 0.01 permin vs 0.110 +/- 0.01 per min; P < 0. 025) was found increased in patients as opposed to controls. The t(1/2) of exogenously administered TRH was increased in ESS compared with controls (7.2 +/- 0.7 min vs 6.3 +/- 0.6 min; P <0.005). TSH response to TRH was found significantly repressed at 10, 20 and 30 min after TRH injection. On d2, these findings had reverted to normal and no changes regarding the kinetics of TRH and the response of TSH could be detected between patients and controls.

CONCLUSIONS

The results demonstrate an impairment of TRH metabolism in ESS. The findings may suggest altered enzymatic activity, responsible for TRH degradation in states of acute ESS. These changes might be involved in the pathogenesis of ESS and represent part of an adaptive mechanism to this syndrome.

Correlations among expression of glomerular intercellular adhesion molecule 1 (ICAM-1), levels of serum soluble ICAM-1, and renal histopathology in patients with IgA nephropathy

The purpose of the present study was to evaluate the correlations among expression of intercellular adhesion molecule 1 (ICAM-1) in glomeruli, levels of soluble ICAM-1 (sICAM-1) in sera, and renal injuries in patients with IgA nephropathy. The levels of sICAM-1 in sera from 27 patients with IgA nephropathy and 7 healthy controls were measured by the human soluble ICAM-1 immunoassay. The expression of ICAM-1 in glomeruli was detected by indirect immunofluorescence. We observed marked expression of ICAM-1 in glomerular capillary walls and mesangial areas in patients with advanced-stage, but not in those with mild IgA nephropathy. Since the histopathological changes in the advanced stage of this disease were characterized by diffuse mesangial cell proliferation and tubulointerstitial injury, the expression of ICAM-1 in the glomeruli may be of value in evaluating the degree of renal lesions in patients with IgA nephropathy. However, there was no significant change in the levels of serum sICAM-1 among mild-stage and advanced-stage patients and healthy controls. It appears that the measurement of serum sICAM-1 is not useful in evaluating the degree of renal injuries in patients with IgA nephropathy.

Nightmare distress and stress-related health problems

Responses of 289 university students to Belicki's Nightmare Distress Questionnaire and the Stress-related Health Problems Scale were used to test the hypothesis that persons who score high on nightmare distress are more likely to report psychological problems. Since relative to the Low Nightmare Distress group, the High Nightmare Distress group scored significantly higher on all seven of the sets of symptoms that are measured by the Stress-related Health Problems Scale, this hypothesis was supported.

Expression and characterization of elastase inhibitors from the ascarid nematodes Anisakis simplex and Ascaris suum

Two elastase inhibitors, ASPI-1 and ASPI-2, from the parasitic nematode Anisakis simplex, have been isolated and characterized. Because these inhibitors are similar in size (60 amino acids in length) and primary sequence (52 and 47% identical) to the Ascaris suum chymotrypsin/elastase inhibitor-1 (AsC/E-1), we suggest that these Anisakis elastase inhibitors belong to the same unique class of canonical inhibitors formed by the family of Ascaris inhibitors (Huang K, Strynadka NCJ, Bernard VD, Peanasky RJ, James MG. Structure 1994;2:679-689). To compare ASPI-1 with AsC/E-1, we expressed both inhibitors in Pichia pastoris and found that: (1) the association constant of rASPI-1 with porcine pancreatic elastase (PPE) is similar to native inhibitor (Ka = 4.5 x 10(9) and 6.4 x 10(9) M(-1), respectively); (2) rASPI-1 is a potent inhibitor of PPE and human leukocyte elastase (Ka = 1.6 x 10(9) M(-1)); and (3) it is only a very weak inhibitor of chymotrypsin (CHYM) (Ka = 1.2 x 10(6) M(-1)). In contrast to the Anisakis inhibitor, however, rAsC/E inhibitor-1 is a very strong inhibitor of both PPE (Ka = 3.5 x 10(10) M(-1)) and CHYM (Ka = 3.6 x 10(12) M(-1)). We also found that the determined reactive sites (P1-P'1) of rASPI-1 and rAsC/E-1, as recognized by PPE, are Ala 28-Met 29 and Leu 31-Met 32, respectively. These P1-P'1 residues of AsC/E-1 constitute the same reactive site as that also recognized by CHYM (Peanasky RJ, Bentz Y, Homandberg GA, Minor ST, Babin DR. Arch Biochem Biophys 1994;232:135-142). The difference in specificities of ASPI-1 and AsC/E-1 toward their cognate serine proteases may be attributed to the P1 and P'3 residues in the inhibitors. Elastase, which recognizes both alanine and leucine, canaccommodate both ascarid inhibitors, whereas chymotrypsin, which prefers bulky, hydrophobic residues, only recognizes the Ascaris C/E inhibitor-1.

Orally bioavailable nonpeptide vitronectin receptor antagonists containing 2-aminopyridine arginine mimetics

A peptide RGD analog containing a novel 2-aminopyridine arginine mimetic was discovered to have good affinity and selectivity for the vitronectin receptor. Incorporation of the 2-aminopyridine arginine mimetic into the 3-oxo-1,4-benzodiazepine-2-acetic acid integrin antagonist series led to novel and potent nonpeptide vitronectin receptor antagonists with promising levels of oral bioavailability.

A variety of gram-positive bacteria carry mobile mef genes

The mefE gene codes for a membrane bound efflux protein, which confers resistance to macrolides, and has been identified in Streptococcus pneumoniae. A variety of gram-positive organisms were examined. Twenty-six isolates of S. pneumoniae carried mefE and were resistant to erythromycin (MIC of 2-16 mg/L). Two additional isolates of Emr S. pneumoniae carried both ermB and mefE(MIC of 16-128 mg/L). One Micrococcus luteus, one Corynebacterium jeikeium, three Corynebacterium spp., two viridans streptococci and seven Enterocccus spp. also carried mef genes. It was possible to move the mef gene from all 11 S. pneumoniae tested to susceptible S. pneumoniae and/or Enterococcus faecalis recipients. The addition of DNase (1 g/L) did not affect the gene transfer. It was also possible to move the mef gene from donor Enterococcus spp., viridans streptococci, M. luteus, C. jeikeium and Corynebacterium spp. to E. faecalis recipients. Transconjugant isolates were resistant to erythromycin (MIC = 16 mg/L). Hybridization with a labelled mef oligonucleotide probe against Southern blots and bacterial dot blots confirmed the presence of the mef genes. This is the first time that a mobile mef gene has been identified in four different genera, from three distinct geographical locations.