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Objective: To examine the effect of worker heterogeneity, firm size, and establishment size on the breadth of employer health insurance offerings., Data Sources: The data were drawn from the 1993 Robert Wood Johnson Foundation Employer Health Insurance Survey of 22,000 business establishments selected randomly from ten states., Study Design: The analysis was cross-sectional, using ordered probit models to relate the breadth of plan offerings to firm characteristics., Principal Findings: Firms with more diverse workforces offered a more diverse set of health insurance options. Firm and establishment size independently influenced the breadth of plan offerings., Conclusions: Employers are responsive to worker heterogeneity when determining the breadth of their health insurance offerings. However, diseconomies of scale in the purchase and administration of health insurance appear to limit the extent to which small employers can accommodate diverse worker preferences.

The important human pathogen Streptococcus pyogenes (the group A streptococcus or GAS) causes diseases ranging from mild, self-limiting pharyngitis to severe invasive infections. Regulation of the expression of GAS genes in response to specific environmental differences within the host is probably key in determining the course of the infectious process, however, little is known of global regulators of gene expression in GAS. Although secondary RNA polymerase sigma factors act as global regulators of gene expression in many other bacteria, none has yet been isolated from the GAS. The newly available GAS genome sequence indicates that the only candidate secondary sigma factor is encoded by two identical open reading frames (ORFS). These ORFS encode a protein that is 40% identical to the transcription factor ComX, believed to act as an RNA polymerase sigma factor in Streptococcus pneumoniae. To test whether the GAS ComX homologue functions as a sigma factor, we cloned and purified it from Escherichia coli. We found that in vitro, this GAS protein, which we call sigmaX, directed core RNA polymerase from Bacillus subtilis to transcribe from two GAS promoters that contain the cin-box region, required for transcription by S. pneumoniae ComX in vivo. On the other hand, GAS sigmaX did not promote transcription of a GAS promoter (hasA) expected to be dependent on sigmaA, the housekeeping or primary RNA polymerase sigma factor. Addition of monoclonal antibody that inhibited sigmaA-directed transcription had no effect on sigmaX-directed transcription, showing that the latter was not the result of contaminating sigmaA. Transcription of both cin-box-containing promoters initiated downstream of the cin-box and two different single basepair substitutions in the cin-box of the cinA promoter each caused a severe reduction of sigmaX-directed transcription in vitro. Thus, the cin-box is required for sigmaX-directed transcription.

This study evaluated nitrogen and energy utilization by male and female broilers that were at 46 and 54 d of age fed diets deficient or adequate in threonine. Birds were reared in floor pens of an open-sided house and were provided diets that met NRC (1994) nutrient recommendations from placement until 6 wk of age. At 42 d, 48 birds (24 per sex) were selected and individually penned in Petersime batteries and were given feeds that were formulated to contain 0.52 or 0.74% total threonine having 18% CP and 3,200 kcal ME/kg. Two 24-h excreta collection periods were conducted on Days 46 and 54 to assess nitrogen and energy recovery. Males receiving adequate threonine had an advantage in retention of nitrogen and recovery of AMEn over males consuming the low threonine diet. Utilization of nitrogen by females was similar at both threonine concentrations, and AMEn corresponded to the concentration recovered by males when threonine was adequate. Inadequate threonine appears to create conditions that reduce recovery of energy by male broilers.

Purpose: To demonstrate analytical methods for evaluating the results of keratorefractive surgical procedures and emphasize the importance of intraocular astigmatism., Setting: University of Texas Medical School, Houston, Texas, USA., Methods: A standard data set, provided by an editor of this journal, comprising the preoperative and postoperative keratometric and refractive measurements of 100 eyes that had keratorefractive surgery was evaluated by 2 methods, vector and spheroequivalent (SEQ) analysis. The individual and aggregate surgically induced refractive changes (SIRCs) and prediction errors were determined from the refractive and keratometric measurements using both methods and then compared. The refraction vertex distance, keratometric index of refraction, and corneal asphericity were used to make the results calculated from refractive data directly comparable to those derived from keratometric data. Doubled-angle and equivalency plots as well as frequency and cumulative histograms were used to display the data. Standard descriptive statistics were used to determine the mean and standard deviation of the aggregate induced astigmatism after converting the polar values (cylinder and axis) to Cartesian (x and y) values., Results: The preoperative SEQ refractive errors were undercorrected by at least 0.25 diopter (D) in most cases (78%). Six percent were corrected within +/- 0.24 D, and 16% were overcorrected by at least 0.25 D SEQ. The mean SEQ was -6.68 D +/- 2.49 (SD) before and -0.61 +/- 0.82 D after surgery, reflecting a SIRC SEQ of -6.07 +/- 2.40 D. The defocus equivalent (DEQ) was 7.41 +/- 2.53 D before and 0.96 +/- 0.74 D after surgery; for a nominal 3.0 mm pupil, this corresponded to an estimated improvement in uncorrected visual acuity (UCVA) from worse than 20/200 to better than 20/25, respectively. The predictability of the treatment decreased as the attempted refractive correction increased. The average magnitude of the refractive astigmatism was 1.46 +/- 0.61 D before and 0.40 +/- 0.38 D after surgery. The centroid of the refractive astigmatism was +0.96 x 87.9 +/- 0.85 D, rho = 0.43 before and +0.11 x 83.1 +/- 0.37, rho = 0.49 after surgery. The decrease in the square root of the centroid standard deviation shape factor (rho1/2) indicated an 8% increase in the amount of oblique astigmatism in the population. The prevalence of preoperative keratometric irregular astigmatism in excess of 0.5 D in this group of patients was 13%. The correlation between keratometric and refractive astigmatism was extremely poor before (r2 = 0.26) and especially after surgery (r2 = 0.02), demonstrating the presence of intraocular astigmatism and the limitations of manual keratometry. The centroid of intraocular astigmatism at the corneal plane was +0.48 x 178 +/- 0.49 D, rho = 0.59, and was compensatory., Conclusions: The 2 analytical methods are complimentary and permit thorough and quantitative evaluation of SIRCs and allow valid statistical comparisons within and between data sets. The DEQ allows comparison of refractive and visual results. The decrease in refractive predictability with higher corrections is well demonstrated by the SEQ and doubled-angle plots of the SIRC. Doubled-angle plots were particularly useful in interpreting errors of cylinder treatment amount and errors in alignment. The correlation between refractive and keratometric astigmatism was poor for preoperative, postoperative, and SIRC data, indicating the presence of astigmatic elements beyond the corneal surface (ie, intraocular astigmatism). Sources of error in refractive outcome statistics include the use of multiple lens systems in the phoropter, errors in vertex calculations, difficulty in accurately defining the axis of astigmatism, and failure to consider measurement errors when working with keratometric data. The analysis of this particular data set demonstrates the significant clinical benefits of refractive surgery: an 8-fold increase in UCVA, an 11-fold decrease in SEQ refractive error, as well as a 9-fold and nearly a 2 1/2-fold decrease in the magnitude and distribution of astigmatism, respectively.

During endospore formation in Bacillus subtilis, over two dozen polypeptides are assembled into a multilayered structure known as the spore coat, which protects the cortex peptidoglycan (PG) and permits efficient germination. In the initial stages of coat assembly a protein known as CotE forms a ring around the forespore. A second morphogenetic protein, SpoVID, is required for maintenance of the CotE ring during the later stages, when most of proteins are assembled into the coat. Here, we report on a protein that appears to associate with SpoVID during the early stage of coat assembly. This protein, which we call SafA for SpoVID-associated factor A, is encoded by a locus previously known as yrbA. We confirmed the results of a previous study that showed safA mutant spores have defective coats which are missing several proteins. We have extended these studies with the finding that SafA and SpoVID were coimmunoprecipitated by anti-SafA or anti-SpoVID antiserum from whole-cell extracts 3 and 4 h after the onset of sporulation. Therefore, SafA may associate with SpoVID during the early stage of coat assembly. We used immunogold electron microscopy to localize SafA and found it in the cortex, near the interface with the coat in mature spores. SafA appears to have a modular design. The C-terminal region of SafA is similar to those of several inner spore coat proteins. The N-terminal region contains a sequence that is conserved among proteins that associate with the cell wall. This motif in the N-terminal region may target SafA to the PG-containing regions of the developing spore.

Many biological processes are mediated through the action of multiprotein complexes, often assembled at specific cellular locations. Bacterial endospores for example, are encased in a proteinaceous coat, which confers resistance to lysozyme and harsh chemicals and influences the spore response to germinants. In Bacillus subtilis, the coat is composed of more than 20 polypeptides, organized into three main layers: an amorphous undercoat; a lamellar, lightly staining inner structure; and closely apposed to it, a striated electron-dense outer coat. Synthesis of the coat proteins is temporally and spatially governed by a cascade of four mother cell-specific transcription factors. However, the order of assembly and final destination of the coat structural components may rely mainly on specific protein-protein interactions, as well as on the action of accessory morphogenetic proteins. Proteolytic events, protein-protein crosslinking, and protein glycosylation also play a role in the assembly process. These modifications are carried out by enzymes that may themselves be targeted to the coat layers. Coat genes have been identified by reverse genetics or, more recently, by screens for mother cell-specific promoters or for peptide sequences able to interact with certain bait proteins. A role for a given locus in coat assembly is established by a combination of regulatory, functional, morphological, and topological criteria. Because of the amenability of B. subtilis to genetic analysis (now facilitated by the knowledge of its genome sequence), coat formation has become an attractive model for the assembly of complex macromolecular structures during development., (Copyright 2000 Academic Press.)

During endospore formation in Bacillus subtilis, the DNA binding protein GerE stimulates transcription from several promoters that are used by RNA polymerase containing sigmaK. GerE binds to a site on one of these promoters, cotX, that overlaps its -35 region. We tested the model that GerE interacts with sigmaK at the cotX promoter by seeking amino acid substitutions in sigmaK that interfered with GerE-dependent activation of the cotX promoter but which did not affect utilization of the sigmaK-dependent, GerE-independent promoter gerE. We identified two amino acid substitutions in sigmaK, E216K and H225Y, that decrease cotX promoter utilization but do not affect gerE promoter activity. Alanine substitutions at these positions had similar effects. We also examined the effects of the E216A and H225Y substitutions in sigmaK on transcription in vitro. We found that these substitutions specifically reduced utilization of the cotX promoter. These and other results suggest that the amino acid residues at positions 216 and 225 are required for GerE-dependent cotX promoter activity, that the histidine at position 225 of sigmaK may interact with GerE at the cotX promoter, and that this interaction may facilitate the initial binding of sigmaK RNA polymerase to the cotX promoter. We also found that the alanine substitutions at positions 216 and 225 of sigmaK had no effect on utilization of the GerE-dependent promoter cotD, which contains GerE binding sites that do not overlap with its -35 region.

An experiment was carried out to collect data suitable for testing methods used to describe the potential growth and body composition curves of broilers. Males and females of two commercial broiler strain-crosses were grown to 16 wk of age with birds taken at 0, 2, 4, 6, 8, 12, and 16 wk of age for chemical analysis and for the measurement of feather weight and breast meat (Pectoralis major and Pectoralis minor) weight at these ages. The data were used to test the Gompertz growth equation and the assumption of chemical allometry, as well as to estimate the values of the growth parameters for the different genotypes. Feeding and environmental conditions were intended to be such that potential growth and body composition could be attained. The weights of the chemical components for each of the four genotypes were described in terms of the mature weight of these components, their rates of maturing, and the time taken to reach the maximum rate of growth of each component. Allometric relationships between the weights of the chemical components and that of body protein were estimated. The ratio of ash to protein was essentially constant. Water matured more slowly, and lipid faster, than protein. For males, and for females up to 8 wk, the models were satisfactory. For females after this age, lipid growth was faster than expected from the earlier period, probably in preparation for egg production. There were small, but important, differences in the values of some parameters between the strain-crosses. For each of the four genotypes the changes in weight of feathers and breast meat with time were described in terms of the Gompertz growth function, which described the data very well. The parameters of the function for each component and genotype-mature weight, rate of maturing, and the time taken to reach the maximum rate of growth B were evaluated. For the feathers, the value of the rate parameter was higher than that estimated for the body as a whole. For the two breast muscles, and for their total weight, the value of the rate parameter was similar to that for the body as a whole. There was a simple allometric relationship between the weights of the breast muscles and that of the whole body. As a consequence, the development of the yield of breast meat for a given genotype could be described by the values of the two parameters: mature yield and the allometric exponent. A description of each genotype of interest is seen as an essential first step in using a simulation model either to predict requirements, or to predict the effects of different feeding programs, and environmental conditions, on the performance of broilers.

Bacterial endospores are encased in a complex protein coat, which confers protection against noxious chemicals and influences the germination response. In Bacillus subtilis, over 20 polypeptides are organized into an amorphous undercoat, a lamellar lightly staining inner structure, and an electron-dense outer coat. Here we report on the identification of a polypeptide of about 30 kDa required for proper coat assembly, which was extracted from spores of a gerE mutant. The N-terminal sequence of this polypeptide matched the deduced product of the tasA gene, after removal of a putative 27-residue signal peptide, and TasA was immunologically detected in material extracted from purified spores. Remarkably, deletion of tasA results in the production of asymmetric spores that accumulate misassembled material in one pole and have a greatly expanded undercoat and an altered outer coat structure. Moreover, we found that tasA and gerE mutations act synergistically to decrease the efficiency of spore germination. We show that tasA is the most distal member of a three-gene operon, which also encodes the type I signal peptidase SipW. Expression of the tasA operon is enhanced 2 h after the onset of sporulation, under the control of sigmaH. When tasA transcription is uncoupled from sipW expression, a presumptive TasA precursor accumulates, suggesting that its maturation depends on SipW. Mature TasA is found in supernatants of sporulating cultures and intracellularly from 2 h of sporulation onward. We suggest that, at an early stage of sporulation, TasA is secreted to the septal compartment. Later, after engulfment of the prespore by the mother cell, TasA acts from the septal-proximal pole of the spore membranes to nucleate the organization of the undercoat region. TasA is the first example of a polypeptide involved in coat assembly whose production is not mother cell specific but rather precedes its formation. Our results implicate secretion as a mechanism to target individual proteins to specific cellular locations during the assembly of the bacterial endospore coat.

We report Western blot data showing that the 42.8-kDa product of the previously characterized cotH locus (8) is a structural component of the Bacillus subtilis spore coat. We show that the assembly of CotH requires both CotE and GerE. In agreement with these observations, the ultrastructural analysis of purified spores suggests that CotH is needed for proper formation of both inner and outer layers of the coat.

We have identified a locus essential for galacturonate utilization in Bacillus subtilis. Genes homologous to Escherichia coli and Erwinia chrysanthemi glucuronate and galacturonate metabolic genes were found in a cluster consisting of 10 open reading frames (ORFs) in the B. subtilis chromosome. A mutant of B. subtilis containing a replacement of the second and third ORFs was unable to grow with galacturonate as its primary carbon source. Galacturonate induced expression from a sigmaA-dependent promoter, exuP1, located upstream from the first ORF. The eighth ORF in this cluster (the exu locus) encodes a LacI and GalR homolog that negatively regulated expression from exuP1. A 26-bp inverted repeat sequence centered 15 bp downstream from the exuP1 start point of transcription acted in cis to negatively regulate expression from exuP1 under noninducing conditions. Expression from the exuP1 promoter was repressed by high levels of glucose, which is probably mediated by CcpA (catabolite control protein A). A sigmaE-dependent promoter, exuP2, was localized between the second and third ORFs and was active during sporulation.

Infantile regurgitation is a frequently occurring problem. Throughout the world, anxious parents are imploring physicians to eliminate their infant's regurgitation. General practitioners, pediatricians and pediatric gastroenterologists strive to alleviate infantile regurgitation and its related parental stress. In this paper we define the scope of the problem and analyze the optimal, cost-efficient management approach to simple regurgitation in infants. The intent of this paper is to disseminate this information to practicing physicians and other health care professionals in an attempt to minimize the impact of this annoying problem of infancy and to eliminate confusion and expensive diagnostic tests and use of sub-optimal treatment modalities. Parental reassurance and dietary management by feeding thickened formula are important components in managing regurgitation in infants while maintaining optimal nutritional intake for adequate growth and development.

Bacillus subtilis Spo0A activates transcription from both sigmaA- and sigmaH-dependent promoters. Baldus et al. (2) identified two amino acid substitutions in the carboxyl terminus of sigmaA, K356E and H359R, that specifically impaired Spo0A-activated transcription in vivo. To test the model in which the K356E and H359R substitutions in sigmaA interfere with the interaction of Spo0A and sigmaA, we examined the effects of alanine substitutions at these positions in sigmaA on sigmaA's ability to direct transcription in vivo and in vitro. We found that alanine substitutions at these positions specifically reduced expression from the sigmaA-dependent, Spo0A-dependent promoters, spoIIG and spoIIE, in vivo. Furthermore, we found that stimulation of spoIIG promoter activity by Spo0A in vitro was reduced by the single substitutions H359A and H359R in sigmaA.

The allergy preventive effect of extensively (N) and partially (PH) hydrolysed cows' milk formulas compared with a regular formula (RM) was assessed in 155 infants with a family history of allergy. No cows' milk was given during the first nine months of life and no egg and fish up to 12 months of age. Breast feeding mothers avoided the same foods. At weaning the infants were randomised to one of the formula groups. The cumulative incidence of atopic symptoms at 18 months was 51, 64, and 84% in the N, PH, and RM groups, respectively. From 6 to 18 months there were significantly less cumulative atopic symptoms in the N group compared with the RM group, and significantly less than the PH group up to 6 (N = 25%; PH = 46%) and 9 months (N = 34%, PH = 58%). At 9 months significantly fewer infants in the N group (10%) than in the PH group (33%) had a positive skin prick test to eggs. The findings support an allergy preventive effect of an extensively hydrolysed formula, but not of a partially hydrolysed formula, during the first 18 months of life of high risk infants.

Background: Glucose-based oral rehydration solutions (ORS) available in the United States do not appear to reduce the severity or duration of diarrhea. The use of cereal-derived ORS and cereal-based feedings appears to diminish the severity of illness in studies conducted in the developing world. To our knowledge, no controlled trials of cereal-derived ORS or cereal-based feedings have been performed in the United States., Methods: We performed a randomized, double-blind trial of two ORS feeding regimens in outpatients with diarrhea. Patients aged 2-13 months with acute watery diarrhea were enrolled. Subjects received standard glucose-based ORS in alternation with soy-based, lactose-free infant formula (Group 1) or rice syrup solid containing ORS in alternation with rice-based, lactose-free infant formula (Group 2). Subjects were visited at home daily to determine the severity of illness and characteristics of the stool., Results: After the first 2 days, significantly more Group 1 subjects continued to have diarrhea than did Group 2 subjects (median duration of diarrhea 3 vs. 2 days) as demonstrated by Kaplan-Meier survival curves (p = 0.04)., Conclusion: We conclude that infants fed a regimen consisting of rice syrup solid containing ORS and rice formula resolved their diarrhea sooner than did infants fed a regimen of standard glucose-based ORS and formula. The relative contributions of ORS and formula to this more rapid recovery can be elucidated by further studies.

We cloned and characterized a gene, cotM, that resides in the 173 degrees region of the Bacillus subtilis chromosome and is involved in spore outer coat assembly. We found that expression of the cotM gene is induced during development under sigma K control and is negatively regulated by the GerE transcription factor. Disruption of the cotM gene resulted in spores with an abnormal pattern of coat proteins. Electron microscopy revealed that the outer coat in cotM mutant spores had lost its multilayered type of organization, presenting a diffuse appearance. In particular, significant amounts of material were absent from the outer coat layers, which in some areas had a lamellar structure more typical of the inner coat. Occasionally, a pattern of closely spaced ridges protruding from its surface was observed. No deficiency associated with the inner coat or any other spore structure was found. CotM is related to the alpha-crystallin family of low-molecular-weight heat shock proteins, members of which can be substrates for transglutaminase-mediated protein cross-linking. CotM was not detected among the extractable spore coat proteins. These observations are consistent with a model according to which CotM is part of a cross-linked insoluble skeleton that surrounds the spore, serves as a matrix for the assembly of additional outer coat material, and confers structural stability to the final structure.

Infant formulas containing medium chain triglycerides (MTC) have been used for the nutritional management of infants with fat malabsorption. The optimal proportion of MTC in the formula remains to be determined. Three infant formulas with varying proportion of MTC in the fat blend were studied in children with cystic fibrosis, cholestasis or persistent diarrhea. The formula containing 48% of the total energy from fat and 55% of the fat component as MTC was found to be the most suitable for the needs of those infants. It leads to an adequate essential fatty acid status and to improved recovery in those conditions.

We report on the characterization of three new transcription units expressed during sporulation in Bacillus subtilis. Two of the units, cse15 and cse60, were mapped at about 123 degrees and 62 degrees on the genetic map, respectively. Their transcription commenced around h 2 of sporulation and showed an absolute requirement for sigmaE. Maximal expression of both cse15 and cse60 further depended on the DNA-binding protein SpoIIID. Primer extension results revealed -10 and -35 sequences upstream of the cse15 and cse60 coding sequences very similar to those utilized by sigmaE-containing RNA polymerase. Alignment of these and other regulatory regions led to a revised consensus sequence for sigmaE-dependent promoters. A third transcriptional unit, designated csk22, was localized at approximately 173 degrees on the chromosome. Transcription of csk22 was activated at h 4 of sporulation, required the late mother-cell regulator sigmaK, and was repressed by the GerE protein. Sequences in the csk22 promoter region were similar to those of other sigmaK-dependent promoters. The cse60 locus was deduced to encode an acidic product of only 60 residues. A 37.6-kDa protein apparently encoded by cse15 was weakly related to the heavy chain of myosins, as well as to other myosin-like proteins, and is predicted to contain a central, 100 residue-long coiled-coil domain. Finally, csk22 is inferred to encode a 18.2-kDa hydrophobic product with five possible membrane-spanning helices, which could function as a transporter.

This study tested the effects of light schedules on performance and yields of broiler chickens. In Experiment 1, light treatments during Days 1 to 49 of age were: 1) 23 h light (L):1 h dark (D); 2) 16L:8D;3) 16L: 3D:1L:4D; and 4) 16L:2D:1L:2D:1L:2D. In Experiment 2, Light Treatments 1 and 2 were the same as Treatments 1 and 4, respectively, in Experiment 1; 3) 23L:1D Days 1 to 7, 16L:8D Days 8 to 14, the light period was increased by 2 h/wk during Days 15 to 35, and 23L:1D Days 36 to 42; and 4) 23L:1D Days 1 to 7, 16L:8D Days 8 to 14, 16L:3D: 2L:3D Days 15 to 21, 16L:2D:4L:2D Days 22 to 28, 16L: 1D:6L:1D Days 29 to 35, and 23L:1D thereafter. In Experiment 1, BW was greater in Treatment 4 than Treatment 2 at 22 (708 vs 642 g) and 49 d (2,948 vs 2,797 g), percentage leg problems was lower in Treatments 2 to 4 (9, 10 and 6%, respectively) than in Treatment 1 (20%), and percentage Grade A was greater in Treatment 4 than Treatment 2 (60 vs 46%) at 49 d. In Experiment 2, BW was greater in Treatment 1 (692 g) than Treatments 3 (617 g) and 4 (620 g) at 21 d, and the incidence of tibial dyschondroplasia was lower in Treatment 2 (3.1%) than Treatment 3 (15.3%) at 42 d. There were no differences for mortality among treatments in either experiment.

We used potassium permanganate (KMnO4) to identify unpaired thymidine (T) residues in promoter complexes formed by RNA polymerase (RNAP) associated with sigma E (sigma E-RNAP) from Bacillus subtilis. We found that a region of the spoIIID promoter from at least -10 to +1 becomes melted in the presence of this polymerase. In promoter complexes formed by RNAP associated with a mutant sigma E that melts promoter DNA inefficiently, we noted additional KMnO4 sensitivity at the -11 position of the spoIIID promoter. We suggest that the base pair at -11 is unpaired in both mutant and wild type (wt) complexes; however, close proximity of wt sigma E-RNAP with the T at -11 may protect it from KMnO4 attack. The absence of a close contact between the mutant sigma E-RNAP and the base at -11 may explain why this polymerase uses promoters less efficiently than wt sigma E-RNAP.

To identify genes expressed at intermediate stages of Bacillus subtilis sporulation, we screened for sigma E-dependent promoters. One promoter that we found drives expression of an operon consisting of at least five open reading frames (ORFs). The predicted products of the first three ORFs are very homologous to enzymes involved in fatty acid metabolism, including acetyl coenzyme A (acetyl-CoA) acetyltransferase (thiolase), 3-hydroxybutyryl-CoA dehydrogenase, and acyl-CoA dehydrogenase, respectively. We showed that the fourth ORF encoded a third isozyme of citrate synthase in B. subtilis. Genetic evidence and primer extension results showed that transcription of this operon is directed by the mother cell compartment-specific sigma factor, sigma E, and so the operon was named mmg (for mother cell metabolic genes). Furthermore, we found that a sequence (mmgO) with homology to a catabolite-responsive element mediates glucose repression of mmg promoter activity during sporulation and that this repression was lost in a ccpA mutant.

Six-week-old broilers were compared in yield and weep loss when stunned using either 25 or 125 mA current followed by slush-ice chilling where resultant carcasses were either held static for 4 h or subjected to 45 m of tumbling. Treatments were factorially arranged among the populations of 32 pens (24 birds per pen) that had been reared under common conditions. Tumbling increased chill water uptake, abdominal fat content, and yield of whole carcasses, whereas no differences occurred as a result of the stunning treatments. Carcasses were separated into a nine-piece cut immediately after chilling. All parts lost weight from weepage during the subsequent 24 h, and weep from total parts was greater when carcasses had been tumbled than held static. Keel portion breasts and drumsticks continued a weight advantage from water uptake with tumble chilling, but wings, thighs, and split breast lost this additional water and were similar to those respective parts static chilled. High stunning current led to an increased amount of keel portion breast, regardless of chilling treatment, with subsequent weep not being affected. Alterations in yield that occur because of chilling procedure are substantial and not equivalent among parts, whereas stunning has little impact and is focused on the breast.

An oral electrolyte solution made with rice syrup solids was found to reduce fecal output more effectively than a comparable glucose-based solution in the early hours of treatment of infantile diarrhea. Administration of the rice syrup solids solution was also more effective in promoting absorption of fluid, sodium, and potassium. In some infants, the rapid, effective rehydration offered by this solution may prevent the need for hospitalization.

Broiler males were examined for their response to feeds containing CP 1 to 2% below levels advocated by NRC (1994) and when supplemented with L-glutamic acid. Crude protein and glutamic acid treatments were imposed in starting, growing, and finishing feeds over 7 wk with K at high and low levels likely to occur in practice (0.80 vs 0.65 to 0.55%). All feeds were formulated to be isocaloric (3.20 kcal ME/g) and satisfy NRC (1994) essential amino acid (EAA) minimum requirements. Improved live weight gain occurred during the first 6 wk with supplementation of glutamic acid to the low CP feed but not when intact protein per se was used to increase CP. A similar advantage in growth was obtained from glutamic acid in response to its addition at equivalence of 1 to 2% CP as well as when dietary adjustments maintained low CP. Response to altered K could not be interpreted because of concurrent differences in glutamic acid and AMEn intakes. High glutamic acid levels did not decrease abdominal fat unless CP increased concurrently, whereas carcass back bruising and drumstick deformations were relieved by supplemental glutamic acid independent of CP. Increased weight gain from glutamic acid was only evident with drumsticks and debris that included the back when carcasses were cone-deboned. Supplemental glutamic acid is believed to improve the rate of connective tissue formation during rapid growth.

We have examined the role of the most highly conserved region of bacterial RNA polymerase sigma factors by analyzing the effect of amino acid substitutions and small deletions in sigma E from Bacillus subtilis. sigma E is required for the production of endospores in B. subtilis but not for vegetative growth. Strains expressing each of several mutant forms of sigE were found to be deficient in their ability to form endospores. Single amino acid substitutions at positions 68 and 94 resulted in sigma factors that bind with less affinity to the core subunits of RNA polymerase. The substitution at position 68 did not affect the stability of the protein in B. subtilis; therefore, this substitution probably did not have large effects on the overall structure of the sigma factor. The substitution at position 68 probably defines a position in sigma E that closely contacts a subunit of RNA polymerase, while the substitution at position 94 may define a position that is important for protein stability or for binding to core RNA polymerase.

The outermost protective structure found in endospores of Bacillus subtilis is a thick protein shell known as the coat, which makes a key contribution to the resistance properties of the mature spore and also plays a role in its interaction with compounds able to trigger germination. The coat is organized as a lamellar inner layer and an electron-dense outer layer and has a complex polypeptide composition. Here we report the cloning and characterization of an operon, cotJ, located at about 62 degrees on the B. subtilis genetic map, whose inactivation results in the production of spores with an altered pattern of coat polypeptides. The cotJ operon was identified by screening a random library of lacZ transcriptional fusions for a conditional (inducer-dependent) Lac+ phenotype in cells of a strain in which the structural gene (spoIIGB) for the early-acting, mother-cell-specific transcriptional factor sigma E was placed under the control of the IPTG (isopropyl-beta-D-thiogalactopyranoside)-inducible Pspac promoter. Sequence analysis of cloned DNA from the cotJ region complemented by genetic experiments revealed a tricistronic operon preceded by a strong sigma E-like promoter. Expression of an SP beta-borne cotJ-lacZ fusion commences at around h 2 of sporulation, as does expression of other sigma E-dependent genes, and shows an absolute requirement for sigma E. Studies with double-reporter strains bearing a cotJ-gusA fusion and lacZ fusions to other cot genes confirmed that expression of cotJ is initiated during sporulation prior to activation of genes known to encode coat structural proteins (with the sole exception of cotE). An in vitro-constructed insertion-deletion mutation in cotJ resulted in the formation of spores with no detectable morphological or resistance deficiency. However, examination of the profile of electrophoretically separated spore coat proteins from the null mutant revealed a pattern that was essentially identical to that of a wild-type strain in the range of 12 to 65 kDa, except for polypeptides of 17 and 24 kDa, the putative products of the second (cotJB) and third (cotJC) cistrons of the operon, that were missing or reduced in amount in the coat of the mutant. Polypeptides of the same apparent sizes are detected in spores of a cotE null mutant, on which basis we infer that the products of the cotJ operon are required for the normal formation of the inner layers of the coat or are themselves structural components of the coat. Because the onset of cotJ transcription is temporally coincident with the appearance of active sigma E, we speculate that the cotJ-encoded products may be involved in an early state of coat assembly.

Objective: To compare the efficacy of two commonly used solutions in the rehydration of infants with mild to moderate dehydration caused by acute diarrhea in the United States., Design and Setting: Double-blind, parallel-group, randomized study performed at Children's Hospital Medical Center., Patients: Sixty infant boys (< or = 2 years old), with mild (< or = 5%) or moderate (6 to 9%) dehydration caused by acute diarrhea of less than 1 week's duration were included in the study., Interventions: Infants were randomly assigned to receive treatment with either a glucose-based oral rehydration solution (ORS) (Pedialyte, Ross Laboratories, Columbus, OH) or a rice syrup solids-based ORS (Infalyte, Mead Johnson Nutritional Group, Evansville, IN). After rehydration was achieved, patients entered a maintenance phase during which, in addition to a maintenance ORS, breast milk or a soy-based formula was offered; infants older than 1 year were also given a lactose-free diet., Outcome Measures: Rehydration was judged clinically. Infants remained on a metabolic bed during the study in to separate and quantitate urine and stool output. Therefore, in addition to clinical outcome, we compared intake, output and apparent absorption and retention of fluid, sodium, and potassium between groups., Results: All patients were successfully rehydrated using an ORS without the use of intravenous fluids. No differences were detected between treatment groups in time to rehydration, percentage of weight gain after rehydration, consumption of ORS to achieve rehydration, or stool output. However, the apparent sodium absorption (net intake less fecal output) was greater in the Infalyte group than the Pedialyte group during the first 24 hours., Conclusion: The two maintenance oral electrolyte solutions (Pedialyte and Infalyte) most commonly used in the United States are effective as rehydration solutions for infants with mild to moderate dehydration. We speculate that a strategy for oral rehydration therapy in the United States, based on the use of a single solution during the rehydration and maintenance phase, might gain additional acceptance by practicing pediatricians and family physicians.

Purpose: The purpose of this review is to provide an overview of a wide range of potentially useful strategies to address the prevention of alcohol misuse among American Indians. This broad approach to the review is useful because the extreme heterogeneity of the American Indian population requires that health promotion professionals explore many options and tailor their activities to specific communities., Search Method: A literature search was initiated through MEDLINE using the following key words: prevention, alcohol, substance abuse, American Indian, and Native American. The search yielded 29 articles from the years 1982 through 1994. These articles, along with 45 previously identified in three overview articles, form the basis of the review and discussion in this paper., Summary of Findings: As a group, American Indians experience many health problems that are related to alcohol misuse. Comparison of Indians to non-Indians shows that the age of first involvement with alcohol is younger, the frequency and amount of drinking is greater, and negative consequences are more common. Health promotion programs that address these issues must take into account American Indian heterogeneity and should use a comprehensive approach that addresses both heavy drinking and the sequelae of problems related to alcohol misuse., Major Conclusions: Important concepts for providing health promotion services to this population are: cultural relevance must be carefully planned and monitored; individuals in the local community must be involved; the drunken Indian stereotype must be addressed; and community empowerment should be an important goal.

Pyridyl and 1,6-dihydropyridyl ranitidine analogues 1 and 2 were obtained by applying an improved modification of ranitidine synthesis. Compound 1 shows a selective H2 antagonistic activity while compound 2 is a non-selective histamine antagonist.

The Bacillus subtilis RNA polymerase sigma factor sigma G is a cell-type-specific regulatory protein that governs the transcription of genes that are expressed at an intermediate to late stage of sporulation in the forespore compartment of the sporangium. Here we report the identification of a mutation (lon-1) that causes inappropriate transcription of genes under the control of sigma G under nutritional and genetic conditions in which sporulation is prevented. The mutation is located at 245 degrees on the genetic map and lies within a newly identified open reading frame that is predicted to encode a homolog to Lon protease. Inappropriate transcription of sigma G-controlled genes in the lon-1 mutant is not prevented by mutations in genes that are normally required for the appearance of sigma G during sporulation but is prevented by a mutation in the structural gene (spoIIIG) for sigma G itself. In light of previous work showing that spoIIIG is subject to positive autoregulation, we propose that Lon protease is responsible (possibly by causing degradation of sigma G) for preventing sigma G-directed transcription of spoIIIG and hence the accumulation of sigma G in cells that are not undergoing sporulation. An integrated physical and genetic map is presented that encompasses 36 kb of uninterrupted DNA sequence from the lon pheA region of the chromosome, corresponding to 245 degrees to 239 degrees on the genetic map.

The purpose of this study was to test interactions of dietary lysine or strain crosses provided increased lysine with photoschedule on broiler performance and carcass quality. In Experiment 1, treatments were factorially arranged as two lysine levels [control grower and finisher (NRC, 1984) or control grower and finisher plus .15% L-lysine HCl] and two photoschedules [23 h light (L):1 h dark (D) or 14L:10D]. All birds received a control starter feed and dietary treatments were initiated at 22 d of age. In Experiment 2, treatments were factorially arranged as two strain crosses [Peterson x Arbor Acres (PAA) or Ross x Ross (RR)] and two photoschedules (23L or 16L). All birds received standard starter and standard grower and finisher plus .15% L-lysine HCl. There were no lysine by photoschedule or strain cross by photoschedule interactions in this study. The high-lysine diet increased BW, improved feed efficiency, increased lean carcass weight and yield of breast meat, and decreased abdominal fat and yield of thighs. The PAA strain cross had better feed conversion, fewer Grade A carcasses, more back bruises and breast blisters, greater yield of wings and drumsticks, and less yield of breast meat than RR. The 23L had greater BW, better feed efficiency, fewer breast blisters, greater carcass weight (Experiment 1), more abdominal fat (Experiment 2), lower yield of wings (Experiment 1), drumsticks, and thighs, and greater yield of breast meat than the treatments with shorter photoschedules. Increased dietary lysine did not compensate for decreased breast meat yield associated with 14L (Experiment 1).

Broiler males were given a series of feeds from 0 to 8 wk having all nutrients advocated by the NRC (1984) and were compared with birds offered feeds with available P continuously 10% below recommendation. At termination, birds in pens were divided for cooping, and coops were either subjected to 6 h of truck transportation and 4 h of preslaughter rest or held stationary for 10 h. High summer temperatures existed throughout experimentation, and low dietary P reduced body weight gain through the first 6 wk, whereas an advantage in feed conversion and mortality occurred from 6 to 8 wk. Weight loss increased when birds were subjected to transportation, regardless of P nutriture, and a portion of the loss was recovered during processing as gain in relative chilled carcass yield. Proportions of abdominal fat and skinless boneless meats from chilled carcasses were unaltered, regardless of treatment. Increased incidence of deformed drumsticks occurred because of low P as did drumstick bruising, which was further accentuated when birds had been transported. Back bruising was prominent when P was adequate and birds were held stationary, whereas the converse occurred with transportation. Tibia length was reduced as a consequence of low P, whereas the femur suffered in terms of decreased mineral density at the epiphyses and resistance to Instron-applied stress. Although transportation in itself did not affect any bone measurement, inadequate P weakened the skeleton to increase likelihood of carcass defects during preslaughter stress.

Ross x Arbor Acres (RxAA) and Steggles x Arbor (SxAA) chicks were given all nutrients as advocated by NRC (1984) except for methionine. Corn and soybean meal were the sole CP sources, and both strains were compared when feeds were adequate and deficient in methionine (0 to 3 wk, .65 vs .42% with 24.2% CP and 3.20 kcal AME/g; 3 to 6 wk, .54 vs .46% with 20.7% CP and 3.21 kcal AME; and 6 to 8 wk, .35 vs .30% with 17.8% CP and 3.19 kcal AME, respectively). Cystine exceeded NRC (1984) recommendation with all feeds. Live weights of RxAA broilers were heavier throughout the experiment, but SxAA had the advantage in feed conversion. Adverse effects of low methionine on weight gain were apparent only during the first 6 wk, and SxAA responded to the deficiency more than RxAA from 0 to 3 wk. The SxAA birds had less abdominal fat when processed at both 6 and 8 wk than RxAA. Low methionine increased fat proportions at 6 wk but not at 8 wk. Percentage chilled carcass yield without abdominal fat was similar for each strain and decreased as a result of low methionine at both ages. Low methionine also reduced proportions of skinless boneless breast meat but only at 6 wk and particularly in SxAA birds. The increased ability of RxAA birds to deposit fat enabled additional feed intake, in turn, minimizing repercussion of inadequate methionine.

Spores of the bacterium Bacillus subtilis are encased in a two-layered protein shell, which consists of an electron-translucent, lamellar inner coat, and an electron-dense outer coat. The coat protein CotE is both a structural component of the coat and a morphogenetic protein that is required for the assembly of the outer coat. We now show that CotE is located in the outer coat of the mature spore and that at an intermediate stage of sporulation, when the developing spore (the forespore) is present as a free protoplast within the sporangium, CotE is localized in a ring that surrounds the forespore but is separated from it by a small gap. We propose that the ring is the site of assembly of the outer coat and that the gap is the site of formation of the inner coat. Assembly of the ring depends on the sporulation protein SpoIVA, which sits close to or on the surface of the outer membrane that encircles the forespore. We propose that SpoIVA creates a basement layer around the forespore on which coat assembly takes place. The subcellular localization and assembly of CotE and other coat proteins are therefore determined by the capacity of SpoIVA to recognize and adhere to a specific surface within the sporangium, the outer membrane of the forespore.

Activation of the spoIIG promoter at the onset of sporulation in Bacillus subtilis requires the regulatory protein, Spo0A, which binds to two sites in the promoter, sites 1 and 2. Phosphorylation of Spo0A is essential for the initiation of sporulation. Therefore, we examined the role of Spo0A phosphorylation in spoIIG promoter activation. Phosphorylation of Spo0A stimulated transcription from the spoIIG promoter in vitro. In DNAse I footprinting experiments with the spoIIG promoter, we found that phosphorylation of Spo0A increased its affinity for site 2 more than for site 1, which is the site to which nonphosphorylated Spo0A binds most avidly. This result could not be explained by increased cooperativity between Spo0A bound at sites 1 and 2 because the increased affinity for site 2 by phosphorylated Spo0A was also observed with a deletion derivative of the spoIIG promoter containing only site 2. We have located Spo0A-binding sequences in the spoIIG promoter by DMS protection assays and mutational analysis, and found that site 1 contains one higher-affinity binding sequence whereas site 2 contains two weaker-binding sites. Two substitutions in site 2 of the spoIIG promoter that change the sequence to be more like an optimal Spo0A-binding site were found to increase promoter activity. Moreover, phosphorylation of Spo0A was not required in vivo for activation of the spoIIG promoter containing these strong binding sites. The results suggest that the primary role for phosphorylation of Spo0A is to increase its affinity for specific sites rather than to activate an activity of Spo0A that acts on RNA polymerase at promoters.

During endospore formation in Bacillus subtilis, approximately a dozen proteins are synthesized and assembled around the prespore to form a protective coat. Little is known about the assembly process, but several of the genes encoding these coat proteins are expressed in the mother cell compartment, where the proteins accumulate on the outer side of the developing endospore. Transcription of these genes is directed by the mother cell-specific sigma factor, sigma K, during the later stages of endospore development. sigma E may direct expression of the genes that encode proteins that function in the earliest stages of coat assembly. By screening for sigma E-dependent promoters, we cloned a gene, designated spoVID, required for assembly of a normal spore coat. Expression of spoVID was initiated at about the second hour of sporulation and continued throughout development from a sigma E-dependent promoter. The spoVID gene was located on the B. subtilis chromosome just downstream of the previously characterized hemAXCDBL operon and is predicted to encode an extremely acidic protein with 575 residues. Insertion mutants of spoVID produced refractile spores that were resistant to heat and to chloroform but were sensitive to lysozyme. Electron microscopic examination of sporulating spoVID mutant cells revealed normal morphological development up to about the third hour of sporulation. However, during the later stages of development the coat proteins assembled into aberrant structures that occurred freely in the mother cell cytoplasm and that consisted of reiterations of the single inner and outer layers that normally make up the spore coat.

Genetic evidence suggests that the sigma (sigma) subunit of RNA polymerase determines the specificity of promoter utilization, by making sequence-specific contacts with DNA. We examined the effects of two single amino acid(aa) substitutions in sigma E on the utilization of mutated derivatives of three different promoters in sporulating Bacillus subtilis. We found allele-specific suppression of mutations in all three promoters by each aa substitution in sigma E. These results provide strong evidence that sigma E interacts with each of these promoters in vivo. Moreover, the specificity of suppression of the mutations by the aa substitutions in sigma E lead us to speculate that the Met124 of sigma E closely contacts two adjacent bp in the -10 region of the promoters.

Male poults originating from 41- and 85-wk-old Nicholas Large White breeder turkey hens were compared using a six-feed system provided on the basis of weight. Each source of poult was compared further in its response to lysine at .65 and .80% in the final feed (14.5% CP and 3.40 kcal AMEn/g) before marketing at 18 wk of age. Poults from 85-wk-old hens were heavier at placement than those from 41-wk-old hens. Equalization of body weights occurred once the allotment of starting feed had been consumed and for the most part remained similar thereafter. Increasing lysine content of the final feed did not improve body weight of both sources of birds at marketing (P < .13). Feed conversions included accrued mortality, and treatment differences were not apparent. Commercial processing of the flock and measurements on sample birds indicated no ready differences in chilled carcass yield nor proportions of parts occurred among treatments. The overall effects of breeder age with the progeny were negligible, and the .65% level of lysine that presently serves as the 1984 National Research Council minimum requirement when associated with 14% CP and 3.30 kcal/g appears to be adequate for the Nicholas strain of turkey from 16 to 18 wk of age.

The sigma subunit of bacterial RNA polymerase is required for specific binding to promoters. One region in most sigma factors makes sequence-specific contacts at the -10 region of its cognate promoters. To test the role of the amino acids in this -10 binding region, we examined the effects of 49 single-amino-acid substitutions in sigma E from Bacillus subtilis. We assayed the effect of each amino acid substitution on spore formation because sigma E is essential for endospore formation in B. subtilis. Our results showed that substitutions at several positions, including the highly conserved aromatic amino acid at position 102, had little or no detectable effect. Substitutions at another position, position 117, produced dominant negative mutations; we suggest that these mutations allow RNA polymerase containing the mutant sigma factor to bind specifically to promoters but prevent transcription initiation. Of the recessive defective alleles, those that produced substitutions at positions 113, 115, and 120 produced the most defective sigma factors. These results suggest that the residues at or near these positions in wild-type sigma E play important roles in sigma E function.

Formulas containing proteins with reduced potential to sensitize might be effective in reducing the risk of atopic disease, but such products should be nutritionally adequate. We designed a randomized, double-blind study to evaluate nutritional adequacy and sensitization potential of a formula containing partially hydrolyzed whey-predominant milk proteins. Subjects were term infants enrolled at birth. Infants in group A were fed human milk, and group B received the partially hydrolyzed formula; group C, fed a formula containing intact whey-predominant milk proteins, served as control subjects. We recorded anthropometric measurements and symptoms of formula intolerance at monthly intervals for 4 months in 205 infants. Milk IgE and IgG antibodies were measured until 8 months of age in 63 infants. Daily weight gain was not significantly different among the groups. Gastrointestinal symptoms attributed to feeding intolerance were also comparable. Increases in serum IgG antibodies were significantly greater in group C throughout the study. There were no significant differences in IgE antibodies. Thus a formula containing partially hydrolyzed whey-predominant milk protein promoted adequate growth and induced a lesser priming effect for IgG antibody response than did an intact whey-predominant formula.

A total of 2,560 male broilers from eight commercial strain-crosses were growth to 42 days of age on common starter (1 to 21 days; 23.06% CP, 3,217 kcal ME/kg) and grower (21 to 42 days; 20.14% CP, 3,224 kcal ME/kg) rations. All strain-crossed subsequently received finisher diets (17.95% CP; 3,186 kcal ME/kg) containing either .85 or .95% lysine from 42 to 53 days of age. Further-processing yields were determined on 12 birds per pen, selected within +/- 10% of the replicated pen (8 pens per strain-cross, 40 birds per pen) average weight. The strain-crosses differed significantly (P less than .05) in BW (1, 21, 42, and 53 days), weight gain (WG), feed:gain ratio (1 to 21 and 21 to 42 days), and mortality rate (1 to 21 days). The lysine effect during the finisher period was significant for 53-day BW and WG from 1 to 53 days. Chilled carcass (CC) and abdominal fat (AF) weights, CC yield (percentage, excluding AF), AF yield (percentage of CC weight), Pectoralis major, Pectoralis minor, total deboned breast (TDB), drumstick, thigh, wing, and residual "cage" and skin yields varied among the strain-crosses. A significant weight and yield response to lysine was observed for TDB. Variation observed among strain-cross in live performance, further-processing yields, and response to additional lysine is attributed to differences in rate of growth and degree of maturity at market age. Furthermore, the lysine requirement during the finisher period for optimum breast meat yield may be higher than that recommended by the National Research Council in 1984.

The spoIIE operon is a developmentally regulated transcription unit activated in the second hour of sporulation in Bacillus subtilis. Its promoter has an unusual structure, containing sequences which conform perfectly to the consensus for vegetative promoters recognized by sigma A-associated RNA polymerase (E sigma A), but with a spacing of 21 bp between the apparent -10 and -35 elements instead of the 17- or 18-bp spacing typical of promoters utilized by E sigma A. Mutations introduced into the apparent -10 element affected transcription in a manner consistent with its functioning as a polymerase recognition sequence. The deleterious effect of one -10 mutation was also suppressed in an allele-specific manner by a mutation in sigA known to suppress analogous -10 mutations in conventional vegetative promoters recognized by E sigma A. Similar suppression experiments failed to provide evidence for a direct interaction between E sigma A and the "-35-like" element, however, and DNase I protection experiments suggested instead that the Spo0A protein binds to a site overlapping this -35-like hexamer. Moreover, the effects of mutations within the -35-like hexamer on the binding of Spo0A in vitro paralleled their effects on transcription in vivo. We suggest that spoIIE belongs to a class of early-intermediate sporulation genes whose transcription by E sigma A is activated by the Spo0A protein.

The sigma subunit of bacterial RNA polymerase is required for specific binding of the enzyme to promoters. This specificity is probably directed by two regions of most sigma factors that make sequence-specific contacts at two regions of promoters, the -10 and -35 regions. We found that a single amino acid substitution in the -10 recognition region of sigma E from Bacillus subtilis trapped RNA polymerase in a stable complex with promoter DNA in which it was unable to initiate transcription. Our results are consistent with the view that promoter utilization by RNA polymerase proceeds through several intermediate steps and suggest that the -10 recognition region of sigma factors may participate in a step that follows initial promoter binding.

The spoIIG promoter is used by RNA polymerase containing sigma A (E sigma A), the primary form of RNA polymerase found in vegetative cells in Bacillus subtilis. However, the spoIIG promoter is active only after the onset of sporulation. Activation of the spoIIG promoter requires the product of the spo0A gene (Spo0A). Spo0A is a sequence-specific DNA-binding protein which binds to two sites in the spoIIG promoter that are essential for promoter activity. We found that single-base-pair substitutions in these two regions that reduced promoter activity in vivo caused reduced binding of Spo0A in vitro, and one substitution that increased promoter activity in vivo increased the affinity of Spo0A for this DNA in vitro. Furthermore, Spo0A stimulated transcription from the spoIIG promoter by E sigma A in vitro. These results support the model that binding of Spo0A activates E sigma A-dependent transcription from the spoIIG promoter after the onset of sporulation.

Two experiments were conducted to assess the impact of supplemental L-lysine HCl on N balance in broiler breeder males fed 8% CP corn-based diets (3,220 kcal MEn/kg; .15% supplemental DL-methionine; .24% basal lysine). In Experiment 1, 78-wk-old males were fed the basal diet with either 0, .05, .10, or .25% supplemental L-lysine HCl. Birds were allowed to eat for 1 h each day to a maximum intake of 325 kcal MEn per bird per day. Total excreta were collected for 8 consecutive days. Nitrogen retention and balance were not different among treatments (P greater than .05) and responded neither linearly nor quadratically to dietary lysine level. Removing the variation due to differences in N intake with analysis of covariance did not change the response. In Experiment 2, 30-wk-old males were fed the same basal diet with supplemental lysine levels of 0, .15, .30, .45, .60, and .75% L-lysine HCl for 5 consecutive days. Nitrogen balance and retention were different among diets, and both variates responded linearly to increases in dietary lysine. Removing the variation due to differences in N intake removed treatment effects, however, suggesting that at least part of the difference was the result of variable levels of intake. Regression analysis indicated a significant linear increase in both N balance and retention with increasing dietary lysine level (R2 = .82). These results suggest that young broiler breeder males can make better use of the protein of corn if supplemental lysine is provided. However, older birds do not demonstrate improved N balance as a result of supplemental dietary lysine.

During sporulation in Bacillus subtilis, new RNA polymerase sigma factors are produced. These sigma factors direct the transcription of genes that are required for this cellular differentiation. In order to determine the role of each sigma factor in this process, it is necessary to know which promoters are recognized by each sigma factor. The spoIIID gene product plays an important role in the establishment of mother cell-specific gene expression during sporulation. We found that substitution of an alanine at position 124 of the sporulation-specific sigma factor sigma E suppressed the effect of a single-base-pair transition at position -13 of the spoIIID promoter. This alanine substitution in sigma E did not suppress the effect of a transversion at position -12 of the spoIIID promoter. The allele specificity of the interaction between sigma E and the spoIIID promoter is strong evidence that sigma E directs transcription from the spoIIID promoter during sporulation. Position 124 in sigma E is located within a region that is highly conserved among the regions in other sigma factors that probably interact with the -10 regions of their cognate promoters.

A survey of Anglo and Hispanic adolescent males' sources of sexual information and their attitudes and practices was conducted. A comparison of attitudes and behaviors revealed little difference by ethnicity; however, a more detailed analysis of sources of information resulted in some interesting findings. The relationship between completing a sex education class and condom use was statistically significant in a positive direction. In addition, this relationship was much stronger for Hispanic youth. The important implications of this finding are discussed.