Error rate of automated calculation for wound surface area using a digital photography.

BACKGROUND: Although measuring would size using digital photography is a quick and simple method to evaluate the skin wound, the possible compatibility of it has not been fully validated. PURPOSE: To investigate the error rate of our newly developed wound surface area calculation using digital photography. METHODS: Using a smartphone and a digital single lens reflex (DSLR) camera, four photographs of various sized wounds (diameter: 0.5-3.5 cm) were taken from the facial skin model in company with color patches. The quantitative values of wound areas were automatically calculated. The relative error (RE) of this method with regard to wound sizes and types of camera was analyzed. RESULTS: RE of individual calculated area was from 0.0329% (DSLR, diameter 1.0 cm) to 23.7166% (smartphone, diameter 2.0 cm). In spite of the correction of lens curvature, smartphone has significantly higher error rate than DSLR camera (3.9431±2.9772 vs 8.1303±4.8236). However, in cases of wound diameter below than 3 cm, REs of average values of four photographs were below than 5%. In addition, there was no difference in the average value of wound area taken by smartphone and DSLR camera in those cases. CONCLUSION: For the follow-up of small skin defect (diameter: <3 cm), our newly developed automated wound area calculation method is able to be applied to the plenty of photographs, and the average values of them are a relatively useful index of wound healing with acceptable error rate.

Upregulation of heme oxygenase-1 in oral epithelial dysplasias.

The expression of heme oxygenase-1 (HO-1), stress-related enzyme, is induced in leukaemia and some cancer tissues, but relatively little is known about the differential pattern of HO-1 expression and proliferation in premalignant lesions of the epithelial oral mucosa. The purpose of this study was to evaluate whether HO-1 expression and proliferation were increased in preneoplastic lesions compared to normal and oral cancer tissues. Immunohistochemical staining was used to examine the expression patterns of HO-1 and proliferating cell nuclear antigen (PCNA) in a series of normal mucosa and mild-to-severe cases of oral epithelial dysplasia (OED) and oral squamous cell carcinoma. Both HO-1 and PCNA are expressed in the basal cells of normal oral mucosa. In patients with OED and carcinoma in situ, immunostaining for PCNA and HO-1 was more intense, and gradually extended into the superficial layers of the mucosa. HO-1 and PCNA expression was correlated with the degree of epithelial dysplasia. Oral squamous cell carcinoma also showed elevated expression of HO-1, but this level was not higher than in severe OED or carcinoma in situ. These results suggest that the up-regulation of HO-1 in premalignant oral lesions is part of an early cytoprotection mechanism against carcinogenesis in the oral mucosa.

Characterization of rco-1 of Neurospora crassa, a pleiotropic gene affecting growth and development that encodes a homolog of Tup1 of Saccharomyces cerevisiae.

The filamentous fungus Neurospora crassa undergoes a well-defined developmental program, conidiation, that culminates in the production of numerous asexual spores, conidia. Several cloned genes, including con-10, are expressed during conidiation but not during mycelial growth. Using a previously described selection strategy, we isolated mutants that express con-10 during mycelial growth. Selection was based on expression of an integrated DNA fragment containing the con-10 promoter-regulatory region followed by the initial segment of the con-10 open reading frame fused in frame with the bacterial hygromycin B phosphotransferase structural gene (con10'-'hph). Resistance to hygromycin results from mutational alterations that allow mycelial expression of the con-10'-'hph gene fusion. A set of drug-resistant mutants were isolated; several of these had abnormal conidiation phenotypes and were trans-acting, i.e., they allowed mycelial expression of the endogenous con-10 gene. Four of these had alterations at a single locus, designated rco-1 (regulation of conidiation). Strains with the rco-1 mutant alleles were aconidial, female sterile, had reduced growth rates, and formed hyphae that coiled in a counterclockwise direction, opposite that of the wild type. The four rco-1 mutants had distinct conidiation morphologies, suggesting that conidiation was blocked at different stages. Wild-type rco-1 was cloned by a novel procedure employing heterokaryon-assisted transformation and ligation-mediated PCR. The predicted RCO1 polypeptide is a homolog of Tup1 of Saccharomyces cerevisiae, a multidomain protein that mediates transcriptional repression of genes concerned with a variety of processes. Like tup1 mutants, null mutants of rco-1 are viable and pleiotropic. A promoter element was identified that could be responsible for RCO1-mediated vegetative repression of con-10 and other conidiation genes.

A tactile sensory system of Myxococcus xanthus involves an extracellular NAD(P)(+)-containing protein.

CsgA is a cell surface protein that plays an essential role in tactile responses during Myxococcus xanthus fruiting body formation by producing the morphogenic C-signal. The primary amino acid sequence of CsgA exhibits homology with members of the short-chain alcohol dehydrogenase (SCAD) family and several lines of evidence suggest that NAD(P)+ binding is essential for biological activity. First, the predicted CsgA secondary structure based on the 3 alpha/20 beta-hydroxysteroid dehydrogenase crystal structure suggests that the amino-terminal portion of the protein contains an NAD(P)+ binding pocket. Second, strains with csgA alleles encoding amino acid substitutions T6A and R10A in the NAD(P)+ binding pocket failed to develop. Third, exogenous MalE-CsgA rescues csgA development, whereas MalE-CsgA with the amino acid substitution CsgA T6A does not. Finally, csgA spore yield increased approximately 20% when containing 100 nM of MalE-CsgA was supplemented with 10 microM of NAD+ or NADP+. Conversely, 10 microM of NADH or NADPH delayed development for approximately 24 hr and depressed spore levels approximately 10%. Together, these results argue that NAD(P)+ binding is critical for C-signaling. S135 and K155 are conserved amino acids in the catalytic domain of SCAD members. Strains with csgA alleles encoding the amino acid substitutions S135T or K155R failed to develop. Furthermore, a MalE-CsgA protein containing CsgA S135T was not able to restore development to csgA cells. In conclusion, amino acids conserved in the coenzyme binding pocket and catalytic site are essential for C-signaling.

csgA expression entrains Myxococcus xanthus development.

The development cycle of the myxobacterium Myxococcus xanthus consists of three partially overlapping morphological stages referred to as rippling, fruiting body formation, and sporulation, all of which are absent in csgA null mutants. The CsgA gene product is an extracellular protein, referred to as the C signal, which is essential for developmental cell-cell interactions. csgA expression increases throughout development, reaching its peak during sporulation. CsgA was made limiting for development by constructing nested deletions upstream from the csgA gene, which resulted in reduced csgA expression. Successively larger deletions resulted in termination of development at earlier and earlier stages, with rippling requiring approximately 20% maximum csgA expression, fruiting body formation requiring approximately 30% expression, and sporulation requiring 82% expression. Conversely, artificial induction of csgA also induced development provided nutrients were limiting. These results suggest that steady increases in CsgA over the course of development entrain the natural sequence of morphological events. The csgA upstream region appears to process information concerning the levels of nutrients, peptidoglycan components, and the B signal. In the absence of nutrients, a region extending 400 bp upstream from the start site of transcription was necessary for development and maximal csgA expression. In the presence of low levels of nutrients, a region extending approximately 930 bp upstream was essential for the same tasks. It appears that the upstream region extending from -400 to -930 stimulates csgA expression in the presence of excess carbon, nitrogen, and phosphate, thereby allowing development to go to completion.