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N ecrotizing enterocolitis (NEC) is one of the most common indications for neonatal abdominal surgery. An earlier diagnosis of NEC may reduce subsequent morbidity and mortality. 1 Along with clinical suspicions and laboratory tests, an abdominal x-ray (KUB) is

Background: Free Open-Access Medical education (FOAM) use among residents continues to rise. However, it often lacks quality assurance processes and residents receive little guidance on quality assessment. The Academic Life in Emergency Medicine Approved Instructional Resources tool (AAT) was created for FOAM appraisal by and for expert educators and has demonstrated validity in this context. It has yet to be evaluated in other populations. Objectives: We assessed the AAT's usability in a diverse population of practicing emergency medicine (EM) physicians, residents, and medical students; solicited feedback; and developed a revised tool.

Two lactate dehydrogenase (ldh) genes from Lactobacillus sp. strain MONT4 were cloned by complementation in Escherichia coli DC1368 (ldh pfl) and were sequenced. The sequence analysis revealed a novel genomic organization of the ldh genes. Subcloning of the individual ldh genes and their Northern blot analyses indicated that the genes are monocistronic.Lactobacillus sp. strain MONT4 was isolated from hightemperature-fermenting grape musts (2). It is a unique organism due to its capability of fermenting L-arabinose and ribose exclusively to D(Ϫ)-and L(ϩ)-lactate via a homolactic fermentation pathway (2). Unlike heterolactic fermentations of pentoses that yield equimolar amounts of lactic and acetic acids, homolactic fermentations of pentoses yield only lactic acid and are unknown among lactobacilli. Our long-range goal is to metabolically engineer Lactobacillus sp. strain MONT4 for ethanol production, as it perfectly meets the criteria essential in a commercial biomass-to-ethanol process (25). Metabolic engineering of Lactobacillus sp. strain MONT4 for ethanol production requires the introduction of ethanol production genes into this organism. Moreover, inactivation of the lactate dehydrogenase (ldh) genes is necessary to eliminate coproduct formation.Escherichia coli (pfl ldh) lacks the ability to grow anaerobically on sugars and thus can be used to clone genes from fermentative pathways (1,3,6,7,8,9,10,19,21,24). In order to clone the ldh genes, genomic DNA from Lactobacillus sp. strain MONT4 was partially digested with Sau3AI and was ligated to BamHI-digested pJDC9 (5). E. coli DC1368 transformants were selected on Luria-Bertani medium containing antibiotics (erythromycin, 1 mg per ml; kanamycin, 60 g per ml; chloramphenicol, 60 g per ml) after 48 h of incubation under anaerobic conditions. Four antibiotic-resistant transformants were obtained. One of them, designated E. coli DC1368(pUI100), contained a plasmid with a 5-kb insert (Table 1). When the cell extracts from the transformants were subjected to native polyacrylamide gel electrophoresis and lactate dehydrogenase (LDH) activity staining (11), E. coli DC1368(pUI100) expressed both L(ϩ)-lactate dehydrogenase (LLDH) and D(Ϫ)-lactate dehydrogenase (DLDH) enzymatic activities (Fig. 1).The DNA sequence of the genomic insert from pUI100 was determined (GenBank accession no. AY301012). Eleven open reading frames (ORF) were identified. A 1,002-bp ORF that potentially encodes a 334-amino-acid protein was identified as DLDH. BLAST searches revealed that the nucleotide and deduced amino acid sequences for this ORF have identities of 78 to 90% and 43 to 62%, respectively, to the sequences of published DLDH enzymes from other lactic acid bacteria (LAB) (3,4,10,12,14,15,16,17) (Fig. 2) , and Streptococcus thermophilus LMD-9). At the amino acid level, a 25 to 60% identity and a 45 to 75% similarity within stretches of 244 to 332 amino acids were detected between the deduced amino sequence of the ldhD gene and the translated and annotated genome sequences of 11 LAB stra...