A contract research organization's response to the new FDA guidances for bioequivalence/bioavailability studies for orally administered drug products.

The new FDA Guidance for Industry BA and BE Studies for Orally Administered Drug Products--General Considerations and Average, Population, and Individual Approaches to Establishing Bioequivalence imply significant changes in the areas of enrollment, cost, ethics, time, entry, validation applications (EVAs), and statistical and pharmacokinetic methods. The changes from three-period to two-period design for food effect studies, the elimination of most steady state studies, and the analyses of only the active moiety or ingredient are welcome. However, if the current guidances are adopted, additional time will be needed for participants, and more participants will be needed, resulting in higher costs to drug developers.

Simple method to identify bacteriocin induction peptides and to auto-induce bacteriocin production at low cell density.

The production of some bacteriocins by lactic acid bacteria is regulated by induction peptides (IPs) that are secreted by a dedicated secretion system. The IP gene cbaX, for carnobacteriocin A production by Carnobacterium piscicola LV17A, and a presumptive IP gene (orf6), associated with the genetic locus for enterocin B production in Enterococcus faecium BFE 900, were fused to the signal peptide of the bacteriocin divergicin A from Carnobacterium divergens LV13 to access the general secretory pathway. The culture supernatants of C.

Characterization of the genetic locus responsible for production and immunity of carnobacteriocin A: the immunity gene confers cross-protection to enterocin B.

Carnobacteriocin A (CbnA) is a regulated bacteriocin produced by Carnobacterium piscicola LV17A that is encoded on a 72 kb plasmid. A 10.0 kb fragment from this plasmid that contained information necessary for bacteriocin production and immunity was cloned and sequenced.

Solution structure of carnobacteriocin B2 and implications for structure-activity relationships among type IIa bacteriocins from lactic acid bacteria.

Carnobacteriocin B2 (CbnB2), a type IIa bacteriocin, is a 48 residue antimicrobial peptide from the lactic acid bacterium Carnobacterium pisicola LV17B. Type IIa bacteriocins have a conserved YGNGVXC sequence near the N-terminus and usually contain a disulfide bridge. CbnB2 seemed to be unique in that its two cysteines (Cys9 and Cys14) could be isolated as free thiols [Quadri et al.

The outer membrane of gram-negative bacteria inhibits antibacterial activity of brochocin-C.

Brochocin-C is a two-peptide bacteriocin produced by Brochothrix campestris ATCC 43754 that has a broad activity spectrum comparable to that of nisin. Brochocin-C has an inhibitory effect on EDTA-treated gram-negative bacteria, Salmonella enterica serovar Typhimurium lipopolysaccharide mutants, and spheroplasts of Typhimurium strains LT2 and SL3600. Brochocin-C treatment of cells and spheroplasts of strains of LT2 and SL3600 resulted in hydrolysis of ATP.

Colicin V can be produced by lactic acid bacteria.

Colicin V is a small, proteinaceous bacterial toxin, produced by many strains of Escherichia coli and other members of the Enterobacteriaceae, that fits the definition of class II bacteriocins of Gram-positive bacteria. Export of colicin V is dependent on specific ABC (ATP-binding cassette) secretion proteins which recognize a double-glycine-type leader peptide on the immature colicin V bacteriocin. Replacement of the colicin V leader peptide by a signal peptide from the signal sequence-dependent bacteriocin divergicin A allowed expression of colicin V in lactic acid bacteria.

Enterococci at the crossroads of food safety?

Enterococci are gram-positive bacteria and fit within the general definition of lactic acid bacteria. Modern classification techniques resulted in the transfer of some members of the genus Streptococcus, notably some of the Lancefield's group D streptococci, to the new genus Enterococcus. Enterococci can be used as indicators of faecal contamination.

Atypical genetic locus associated with constitutive production of enterocin B by Enterococcus faecium BFE 900.

A purified bacteriocin produced by Enterococcus faecium BFE 900 isolated from black olives was shown by Edman degradation and mass spectrometric analyses to be identical to enterocin B produced by E. faecium T136 from meat (P. Casaus, T.

Impacts of culture on driver knowledge and safety device usage among Hispanic farm workers.

This study examines Hispanic migrant farm workers' driving behaviors and knowledge of the laws. These laborers worked and drove in California's agricultural region up to 8 months a year. Results are based on 167 face-to-face interviews conducted in Spanish at five labor camps and 126 observations conducted at these same camps in California.

Genetic characterization and heterologous expression of brochocin-C, an antibotulinal, two-peptide bacteriocin produced by Brochothrix campestris ATCC 43754.

Brochocin-C, produced by Brochothrix campestris ATCC 43754, is active against many strains of the closely related meat spoilage organism Brochothrix thermosphacta and a wide range of other gram-positive bacteria, including spores of Clostridium botulinum. Purification of the active compound and genetic characterization of brochocin-C revealed that it is a chromosomally encoded, two-peptide nonlantibiotic bacteriocin. Both peptides of brochocin-C are ribosomally synthesized as prepeptides that are typical of class II bacteriocins.

Influence of vertical vibration on heart rate of pigs.

Pigs with a body weight between 15 and 20 kg were vibrated in the vertical direction for 1 h at 2, 8, and 18 Hz, in combination with root mean square (RMS) acceleration magnitudes of 1 or 3 m/s2. Welfare and stress were quantified by comparing heart rate characteristics during a control period (2200 to 0600) before vibration exposure and during vibration (1000 to 1100). The level of maximum heart rate and number of ventricular ectopic beats during vibration at 2 and 8 Hz in combination with a RMS acceleration of 3 m/s2 indicated a larger fear response than at 1 m/s2.

Iodine status of New Zealand residents as assessed by urinary iodide excretion and thyroid hormones.

The aims of this study were (1) to compare various measures of I status, and (2) to assess urinary I and thyroid hormone status of residents of two areas of New Zealand where, before the iodization of salt, goitre was endemic due to low soil I. A total of 189 subjects (102 males, eighty-seven females) were recruited from the Dunedin Blood Transfusion Centre, and 144 (sixty-seven males, seventy-seven females) from the Waikato Blood Transfusion Centre between November 1993 and June 1994. Blood was taken for thyroid hormone assays, and subjects collected a fasting overnight urine specimen, a double-voided fasting urine sample, and a complete 24 h specimen for iodide and creatinine analyses.

A repeatable method for determination of carboxyhemoglobin levels in smokers.

Fourteen male smokers participated in ten afternoon test sessions to determine the daily variation in expired breath carbon monoxide (CO), and whole blood percent carboxyhemoglobin (%COHb), hemoglobin and hematocrit levels. Each individual's test session was conducted at approximately the same time of day to estimate CO-related measures under relatively stable conditions. Subjects smoked ad libitum prior to testing.

Three-dimensional structure of leucocin A in trifluoroethanol and dodecylphosphocholine micelles: spatial location of residues critical for biological activity in type IIa bacteriocins from lactic acid bacteria.

The first three-dimensional structure of a type IIa bacteriocin from lactic acid bacteria is reported. Complete 1H resonance assignments of leucocin A, a 37 amino acid antimicrobial peptide isolated from the lactic acid bacterium Leuconostoc gelidum UAL187, were determined in 90% trifluoroethanol (TFE)-water and in aqueous dodecylphosphocholine (DPC) micelles (1:40 ratio of leucocin A:DPC) using two-dimensional NMR techniques (e.g.

Stability of Two Concentrations of Heparin Sodium Prefilled in CADD-Micro* Pump Syringes.

The purpose of this study was to determine the stability of two concentrations (1000 units/mL and 40,000 units/mL) of heparin sodium when individually prefilled in CADD-Micro pump syringes (Sims Deltec, Inc., St Paul MN) and stored at near-body (30 deg C) temperature for extended periods of time, up to 30 days. Three syringes were prepared for each sample period and each concentration.

Characterization of a locus from Carnobacterium piscicola LV17B involved in bacteriocin production and immunity: evidence for global inducer-mediated transcriptional regulation.

Mutational, nucleotide sequence, and transcriptional analyses of a 10-kb fragment (carnobacteriocin locus) from the 61-kb plasmid of Carnobacterium piscicola LV17B demonstrated the presence of two gene clusters (cbnXY and cbnSKRTD) upstream of the previously sequenced carnobacteriocin B2 structural and immunity genes (cbnB2 and cbiB2). Deduced products of cbnK and cbnR have sequence similarity to proteins of Agr-type two-component signal transduction systems, and those of cbnT and cbnD have sequence similarity to proteins of signal sequence-independent secretion systems. Deduced products of cbnX, cbnY, and cbnS are class II-type bacteriocin precursors with potential leader peptides containing double-glycine cleavage sites.

Resonant frequencies of standing humans.

Many forms of industrial illness are thought to result from the effects of vibration on the human body. Prolonged exposure causes undue stress and discomfort. At the human whole-body resonant frequency there is maximum displacement between the organs and the skeletal structure and thus this is one frequency of vibration that should be minimized in the workplace and elsewhere.

Lactic acid bacteria of foods and their current taxonomy.

Application of molecular genetic techniques to determine the relatedness of food-associated lactic acid bacteria has resulted in significant changes in their taxonomic classification. During the 1980s the genus Streptococcus was separated into the three genera Enterococcus, Lactococcus and Streptococcus. The lactic acid bacteria associated with foods now include species of the genera Carnobacterium, Enterococcus, Lactobacillus, Lactococcus, Leuconostoc, Oenococcus, Pediococcus, Streptococcus, Tetragenococcus, Vagococcus and Weissella.

Transcriptional analysis and regulation of carnobacteriocin production in Carnobacterium piscicola LV17.

Bacteriocin production by Carnobacterium piscicola LV17 (carnobacteriocin, Cbn) depends on the level of inoculation when grown in liquid medium. With an inoculum of > or = 10(6) colony-forming units per ml (cfu/ml), bacteriocin production is observed during exponential growth, whereas with < or = 10(4) cfu/ml no bacteriocin is detected even when the culture has reached stationary phase. Using pure bacteriocins, it was demonstrated that bacteriocin production is autoregulated.

Double-glycine-type leader peptides direct secretion of bacteriocins by ABC transporters: colicin V secretion in Lactococcus lactis.

Many non-lantibiotic bacteriocins of lactic acid bacteria are produced as precursors which have N-terminal leader peptides that share similarities in amino acid sequence and contain a conserved processing site of two glycine residues in positions -1 and -2. A dedicated ATP-binding cassette (ABC) transporter is responsible for the proteolytic cleavage of the leader peptides and subsequent translocation of the bacteriocins across the cytoplasmic membrane. To investigate the role that these leader peptides play in the recognition of the precursor by the ABC transporters, the leader peptides of leucocin A, lactococcin A or colicin V were fused to divergicin A, a bacteriocin from Carnobacterium divergens that is secreted via the cell's general secretion pathway.

Effect of amino acid substitutions on the activity of carnobacteriocin B2. Overproduction of the antimicrobial peptide, its engineered variants, and its precursor in Escherichia coli.

Carnobacteriocin B2, a 48-amino acid antimicrobial peptide containing a YGNGV motif that is produced by the lactic acid bacterium Carnobacterium piscicola LV17B, was overexpressed as fusion with maltose-binding protein in Escherichia coli. This fusion protein was cleaved with Factor Xa to allow isolation of the mature bacteriocin that was identical in all respects to that obtained from C. piscicola.