The brain-derived neurotrophic factor VAL68MET polymorphism modulates how developmental ethanol exposure impacts the hippocampus.

Prenatal exposure to alcohol causes a wide range of deficits known as fetal alcohol spectrum disorders (FASDs). Many factors determine vulnerability to developmental alcohol exposure including timing and pattern of exposure, nutrition and genetics. Here, we characterized how a prevalent single nucleotide polymorphism in the human brain-derived neurotrophic factor (BDNF) gene (val66met) modulates FASDs severity. This polymorphism disrupts BDNF's intracellular trafficking and activity-dependent secretion, and has been linked to increased incidence of neuropsychiatric disorders such as depression and anxiety. We hypothesized that developmental ethanol (EtOH) exposure more severely affects mice carrying this polymorphism. We used transgenic mice homozygous for either valine (BDNFval/val ) or methionine (BDNFmet/met ) in residue 68, equivalent to residue 66 in humans. To model EtOH exposure during the second and third trimesters of human pregnancy, we exposed mice to EtOH in vapor chambers during gestational days 12 to 19 and postnatal days 2 to 9. We found that EtOH exposure reduces cell layer volume in the dentate gyrus and the CA1 hippocampal regions of BDNFmet/met but not BDNFval/val mice during the juvenile period (postnatal day 15). During adulthood, EtOH exposure reduced anxiety-like behavior and disrupted trace fear conditioning in BDNFmet/met mice, with most effects observed in males. EtOH exposure reduced adult neurogenesis only in the ventral hippocampus of BDNFval/val male mice. These studies show that the BDNF val66met polymorphism modulates, in a complex manner, the effects of developmental EtOH exposure, and identify a novel genetic risk factor that may regulate FASDs severity in humans.

Effect of Aloe vera whole leaf extract on short chain fatty acids production by Bacteroides fragilis, Bifidobacterium infantis and Eubacterium limosum.

AIMS: To investigate the effect of Aloe vera whole leaf extract on pure and mixed human gut bacterial cultures by assessing the bacterial growth and changes in the production of short chain fatty acids. METHODS AND RESULTS: Bacteroides fragilis, Bifidobacterium infantis, and Eubacterium limosum were incubated with Aloe vera extracts [0%, 0.5%, 1%, 1.5% and 2%; (w/v)] for 24 and 48 h. Short chain fatty acids production was measured by gas chromatography/mass spectrometry analyses. A significant linear increase in growth response to Aloe vera supplementation was observed at 24 h for each of the bacterial cultures; however, only B. infantis and a mixed bacterial culture showed a significant positive linear dose response in growth at 48 h. In pure bacteria cultures, a significantly enhanced dose response to Aloe vera supplementation was observed in the production of acetic acid by B. infantis at 24 h and of butyric acid by E. limosum at 24 and 48 h. In the mixed bacterial culture, the production of propionic acid was reduced significantly at 24 and 48 h in a dose-dependent fashion, whereas butyric acid production showed a significant linear increase. CONCLUSIONS: The results indicated that Aloe vera possessed bacteriogenic activity in vitro and altered the production of acetic, butyric and propionic acids by micro-organisms selected for the study. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of the study suggest that consumption of a dietary supplement, Aloe vera, may alter the production of short chain fatty acids by human intestinal microflora.

An evaluation of single-dose metronidazole treatment for Gardnerella vaginalis vaginitis.

A randomized, nonblinded study was carried out to evaluate the efficacy of a single 2-g oral dose of metronidazole (Flagyl) versus a seven-day regimen in the treatment of "nonspecific" vaginitis. Using cultures for Gardnerella vaginalis, 14 (67%) of 21 women treated with the single 2-g dose and 19 (86%) of 21 women receiving the seven-day course were considered cured seven to ten days after treatment (P greater than .10). No difference in compliance was noted between the two groups, and the incidence of side effects likewise, was comparable.

Secondary prevention of coronary heart disease in primary care: a healthy heart initiative.

We assessed the effectiveness of secondary prevention of coronary heart disease (CHD) in primary care, in a cross-sectional study of 1015 patients aged < 75 years with documented CHD. Patients records were examined for documentation of CHD risk factors; 722 patients then attended education sessions where blood pressure and cholesterol were measured, a supervised questionnaire detailing modifiable risk factors was completed, and advice on lifestyle modification was given. Management of risk factors was generally poor, and was worse in women. Approximately 20% of subjects remained hypertensive, with half of these receiving anti-hypertensive medication. Examining the primary care records, serum cholesterol was documented in 17.5% of men and 26.5% of women. Of the 722 subjects who had cholesterol measured, 30% of men and 25% of women had cholesterol < 5.2 mmol/l. Mean cholesterol was significantly higher in the women (6.1 mmol/l vs. 5.6 mmol/l, p = 0.001). Lifestyle risk management was also poor, with significant numbers smoking and drinking more than recommended. Women were more overweight than men (mean BMI 27.9 kg/m2 vs. 26.9 kg/m2, p = 0.006). Aspirin was being taken by 56% of patients.

Ankle biomechanics during four landing techniques.

PURPOSE: An understanding of landing techniques is important for the prevention of injuries in a number of athletic events. There is a risk of injury to the ankle during landings, and the kinematics and forces involved in different landing strategies may be related to the occurrence of trauma. METHODS: In the current study, four drop conditions from a 30.48-cm (12-inch) height were tested. The conditions were a) BN: Bent knee (self-selected), Natural (self-selected) plantar flexor contraction; b) SN: Stiff-knee, Natural plantar flexors; c) SP: Stiff-knee, Plantar flexors absorbing the impact; and d) SH: Stiff-knee, absorbing most of the impact in the Heels. Peak vertical forces and accelerations were measured, and Achilles tendon forces and stiffnesses were calculated. RESULTS: Peak vertical forces and peak tibial accelerations were highest for the SH condition (2418 N and 20.7 G), whereas peak Achilles tendon force was highest for SP drops. The overall average AT stiffness was 166,345 N x m(-1). CONCLUSIONS: The results from the study were used in an extensive cadaver study to investigate ankle injuries. The data from the current study indicate that athletes may not use their full energy absorbing potential in landings during sporting activities.

Validation of a polymerase chain reaction method for the detection of rendered bovine-derived materials in feedstuffs.

This study validated a polymerase chain reaction-based method for the detection of a specific bovine mitochondrial gene derived from rendered bovine tissues and admixed with complete animal feed. Four laboratories participated in this effort: one state laboratory and three Food and Drug Administration (FDA) laboratories, including one FDA field laboratory. The protocol used a statistical approach of 90% probability, with a 95% confidence interval for determining acceptable rates of false-positive and false-negative samples. Each participating laboratory analyzed 30 samples of feed each containing 0, 0.125, and 2.0% bovine meat and bone meal (BMBM), for a total of 90 feed samples. The samples were randomized such that the analysts were unaware of the true identity of the test samples. The results demonstrated that all laboratories met the acceptance criteria established for this protocol. The overall rates of false-negative results were 0.83% (1/120) at the level of 0.125% BMBM and 1.67% (2/120) at the level of 2% BMBM. The overall rate of false-negative results for all levels of BMBM was 1.25% (3/240). The rate for false-positive results was 0.83%.

Impact on empiric treatment of group A streptococcal pharyngitis using an optical immunoassay.

The potential impact of using a rapid diagnostic test (Strep A OIA) on detection and treatment of group A beta-hemolytic streptococcal (GABHS) pharyngitis in a large-volume pediatric and adolescent clinic was examined. Of 519 swabs processed for both culture and the OIA test, 114 were culture-positive for GABHS compared with 133 positive by the OIA test, for an agreement of 94%. OIA test sensitivity compared with culture was 96%, and specificity was 94%. Forty-seven percent of all study patients were empirically placed on antibiotics. In-clinic OIA testing could have reduced inappropriate therapy and been a cost-effective alternative to culture.

Biochemical and molecular characterization of erthromycin-resistant avian Staphylococcus spp. isolated from chickens.

The epidemiology of the two common erythromycin-resistant methylase (erm) genes ermC and ermA was analyzed in 12 coagulase-negative Staphylococcus spp. and 34 coagulase-positive Staphylococcus spp. isolated from chicken. Southern hybridization indicated that only 2 of the 12 coagulase-negative Staphylococcus spp. strains contained the ermC gene on the plasmid; 1 strain of Staphylococcus xylosus harbored the ermC gene on a 2.5-kb plasmid, and 1 strain of Staphylococcus cohnii harbored the gene on a 4.0-kb plasmid. Twelve of the 34 strains of Staphylococcus aureus contained the ermC gene. Eleven of these strains had the ermC gene on a 2.5-kb plasmid, and 1 strain had the gene on a 4.0-kb plasmid. Ten of the 12 coagulase-negative Staphylococcus spp. and 22 of the 34 coagulase-positive Staphylococcus spp. harbored the ermA gene exclusively on the chromosome. Two different ermA EcoRI restriction fragment length polymorphisms (RFLP) were identified. A majority of the isolates was found to have two chromosomal inserts (8.0- and 6.2-kb EcoRI fragments) of ermA. One strain of S. aureus had different chromosomal inserts (6.4- and 5.8-kb EcoRI fragments) of ermA. Our results indicate that either the ermC or ermA gene, homologous to those described in human isolates, was present in all avian Staphylococcus spp. and that ermA was the predominant gene in coagulase-negative and coagulase-positive avian Staphylococcus spp. The size and copy numbers of the ermA gene were different from its human counterpart.

Molecular characterization of fluoroquinolone-resistant Campylobacter spp. isolated from poultry.

Campylobacteriosis, an infectious disease caused by Campylobacter jejuni and Campylobacter coli, is treated by fluoroquinolone antibiotics in clinical practices. However, use of these drugs in animal husbandry may select for fluoroquinolone-resistant campylobacters and, thereby, compromise the clinical treatment of infection. In this study, 21 fluoroquinolone-resistant campylobacters were isolated from poultry samples. Morphological and biochemical characteristics indicated that 19 isolates were C. jejuni and two were C. coli. All isolates were resistant to multiple antibiotics but sensitive to chloramphenicol and gentamicin. These isolates were characterized at the molecular level by amplifying the flagellin gene (flaA) by PCR. The PCR protocol amplified a 1.7-kb flaA gene from all isolates. RFLP analysis of the 1.7-kb amplicons after digestion with DdeI yielded four distinct patterns. The 21 fluoroquinolone-resistant campylobacter isolates were further characterized by pulsed-field gel electrophoresis (PFGE) and compared with the PFGE patterns of nine fluoroquinolone-sensitive campylobacter strains. Four of the 21 fluoroquinolone-resistant isolates were untypable by the PFGE protocol. The PFGE analysis with SalI or SmaI indicated that seven or five, respectively, of the 17 resistant isolates had identical macrorestriction profiles (mrps). However, PFGE analysis with a combination of SalI and SmaI indicated that four of the 17 isolates had similar macrorestriction profiles. The PFGE patterns of the 17 fluoroquinolone-resistant isolates were different from the nine sensitive campylobacter strains.

Effects of Naturally Occurring Aquatic Organic Fractions on Am Uptake by Scenedesmus obliquus (Chlorophyceae) and Aeromonas hydrophila (Pseudomonadaceae).

Naturally occurring organics were extracted from water collected from Skinface Pond near Aiken, S.C. Organics were separated into four nominal diameter size fractions (I, >0.0183; II, 0.0183 to 0.0032; III, 0.0032 to 0.0009; IV, <0.0009 mum) by membrane ultrafiltration and introduced into Scenedesmus obliquus and Aeromonas hydrophila cultures to determine their effects on Am availability for uptake. Effects on Am uptake were determined in actively growing S. obliquus cultures after 96 h of growth and in dense cultures of nongrowing cells after 4 h. Uptake by A. hydrophila was determined after 4 and 24 h in actively growing cultures. All organic fractions stimulated S. obliquus growth, with the most pronounced effects due to larger organic fractions, whereas no apparent growth stimulation of A. hydrophila was observed for any organic fraction. For both long-term and short-term studies, cellular Am concentration (picocuries/cell) increased with increasing Am concentration for S. obliquus and A. hydrophila. Fraction IV increased Am uptake by both S. obliquus and A. hydrophila during 4-h incubations. During 96-h incubations fraction I was flocculated and cosedimented, with S. obliquus and A. hydrophila cells causing an apparent increase in Am uptake. Fractions II and III reduced apparent Am uptake by S. obliquus as a result of biological dilution caused by increased algal growth due to the organics. Fraction IV caused a reduction in Am uptake by S. obliquus not attributable to biological dilution. Organics increased Am uptake by A. hydrophila during 4- and 24-h incubations. A. hydrophila also caused flocculation of fraction I during 96-h incubations.

Derivative absorption and emission spectrophotometry.

Derivative spectrophotometry has been shown to have many important applications: for example, studying composition and reaction processes; providing gas signatures; detecting trace chemicals. This technique can become a powerful means for analyzing isomers used in polymer production. In this report, practical examples are given which typify applications of the derivative spectra. Conventional absorption and emission spectra often present overlapping bands not easily resolved by conventional means; band resolution usually is facilitated by first-and second-derivative spectra obtained from spectrophotometric measurements. Numerical methods based on both off-line and on-line computer processing are presented for generating first-and second-derivative spectra, and these techniques are discussed fully. With these methods, the contribution of background noise is emphasized. Ways to reduce this noise are given.

Large-area plan-view sample preparation for GaAs-based systems grown by molecular beam epitaxy.

We describe a method for plan-view transmission electron microscopy (TEM) sample preparation that takes advantage of extreme etch-rate selectivity in GaAs and AlAs in HF/H2O solutions. GaAs/InxGa1-xAs/GaAs strained-layer films (x = 0.05, 0.10, 0.19, 0.22) were chemically lifted off using this technique and were mounted on Cu TEM grids such that TEM transparent areas of up to 1 x 2 mm of constant thickness (196.4 nm) could be viewed. This simple, large-area plan-view technique uses only chemical methods and significantly extends the usefulness of TEM for the evaluation of crystal quality in GaAs-based epitaxial systems. The method requires the growth of a release layer of AlAs (10 nm thick) prior to the layered structure of interest.

Still's arthritis in adults: disease or syndrome?

Seven adults with a syndrome similar to systemic-onset (Still's) juvenile rheumatoid arthritis are reported. In addition to characteristic fever, rash, and arthritis prominent features included pharyngitis (7), lymphadenopathy (6), pleuropericarditis (4) and progression to joint damage (5). Three were over 50-years-old. Previous reports are reviewed. Symptoms, laboratory and physical findings are broadly comparable to the childhood disease. However findings may be quite variable in individual patients and the diagnosis remains a clinical one. Recognition of the variable presentations of this syndrome will assist in the differential diagnosis of fever of unknown origin.

Phenotypic and genotypic characterization of competitive exclusion products for use in poultry.

AIMS: Phenotypic and genotypic bacteria identification methods were compared for their efficacy in determining the composition of competitive exclusion (CE) products. METHODS AND RESULTS: Phenotypic methods used for bacterial identification were fatty acid methyl ester profiles, biochemical assays and carbohydrate utilization profiles. Genotypic methods were MicroSeq16S rRNA sequence analysis and BLAST searches of the GenBank sequence database. Agreement between phenotypic and genotypic methods for identification of bacteria isolated from the Preempt CE product was 20%. A defined test mixture of bacteria was identified to the species level 100% by BLAST analysis, 64% by MicroSeq and 36% by phenotypic techniques. CONCLUSIONS: The wide range of facultative and obligate anaerobic bacteria present in a CE product are more accurately identified with 16S rRNA sequence analyses than with phenotypic identification techniques. SIGNIFICANCE AND IMPACT OF THE STUDY: These results will provide guidelines for manufacturers of CE products to submit more reliable product information for market approval by regulatory agencies.

Absolute Luminescence Spectra via Digital-Technique and Time-Resolved Spectroscopy.

Most instruments intended for luminescence spectroscopy fall in the category of uncorrected spectrofluorimeters. In many routine analyses, uncorrected spectra are useful, especially if they do not have to be compared with others from different laboratories. However, for theoretical work, results must be on an absolute basis. This paper describes a method and the related equipment that have been developed and used to obtain, on an absolute basis, many of the parameters that are important in photochemical research. The system can provide absolute emission spectra, absolute excitation spectra, and quantum efficiencies for luminescence, fluorescence, delayed fluorescence, and phosphorescence. Also, it can measure the half-life of phosphorescence and of delayed fluorescence. Provision is made for the independent and continuous control of the time between excitation and detection pulses, thus allowing the measurement of the half-life at any wavelength of emission. With these provisions it is possible to resolve overlapping fluorescence, delayed fluorescence, and phosphorescence spectra.

Failure of gamma-interferon to decrease mortality from group B streptococcal sepsis in neonatal rats.

Newborns possess an altered immune response to infection with impaired leukocyte chemotaxis and deficient production of gamma-interferon (IFN-gamma). IFN-gamma enhances neonatal leukocyte activation and movement. We proposed that IFN-gamma in conjunction with penicillin compared to penicillin therapy without IFN-gamma would increase survival from group B streptococcal sepsis in a neonatal rat model. Newborn rats were infected with 10(5) cfu of group B streptococci at 48-72 h of age and randomized to receive either serum albumin (controls), rat recombinant IFN-gamma, albumin and penicillin, or IFN-gamma and penicillin. Survival 120 h postinfection revealed: controls 5% (1/21); IFN-gamma 4% (1/24); penicillin 23% (5/22); and IFN-gamma plus penicillin 10% (2/21). Survival analysis with a lognormal parametric regression model revealed only the penicillin group to have improved survival compared to controls. Contrasting the penicillin group with the IFN-gamma plus penicillin group did not reveal a statistically significant difference by the Wald chi2 statistic (p = 0.25).