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BACKGROUND: The Oral Assessment Guide (OAG) is a widely used tool designed for evaluating problems of oral mucous in cancer patients, but it has not been validated in Spanish. The aim of this work is to translate and validate into Spanish the scale of the OAG designed by Eilers. METHOD: The translation process was carried out using the method of back-translation by bilingual translators. The study was carried out with cancer patients, both outpatient and inpatients, of the Hematology/Oncology Department and with oncology nurses. The following psychometric properties of the OAG were evaluated: internal consistency, concurrent validity with WHO's mucositis scale, interjudge agreement between two different nurses. The perception of patients and nurses on the use of the OAG was also assessed. RESULTS: An adequate Spanish version of the OAG was obtained. All the participants (n=40) completed the study. Internal consistency measured by Cronbach's alpha was 0.71 and interjudge agreement obtained a moderate to good Kappa index in the majority of items (k=0.4-0.81), except in "tongue and gums" (k=0.33-0.37). Concurrent validity with WHO mucositis scale was acceptable (r=0.458). All the nurses (n=6) considered that the scale was easy to understand and useful in clinical practice. The patients said that oral evaluation with the scale did not cause them discomfort. CONCLUSIONS: The Spanish version of the OAG is a valid and reliable instrument in cancer patients. It is a scale that is easy to use in clinical practice and is well accepted by patients.

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Fundamento: El instrumento Oral Assessment Guide (OAG) es una herramienta diseñada y ampliamente utilizada para evaluar problemas de la mucosa oral en pacientes con cáncer, sin embargo no está validada en español. El objetivo de este trabajo es traducir y validar al español la escala de la valoración de la cavidad oral (OAG) diseñada por Eilers. Método: El proceso de traducción se realizó utilizando el método de traducción retrotraducción por bilingües. El estudio se llevó a cabo en pacientes con cáncer ambulatorios y hospitalizados del Departamento Onco-hematológico y con enfermeras que trabajaban con pacientes de cáncer. Se evaluaron las siguientes propiedades psicométricas de la OAG: consistencia interna, validez concurrente con la escala de la mucositis de la OMS, la armonía interjueces entre dos enfermeras diferentes. También se recogió la percepción de los pacientes y enfermeras sobre la utilización de la OAG. Resultados: Se obtuvo una adecuada versión española de la OAG. Todos los participantes (n=40) completaron el estudio. La consistencia interna con el alpha de Cronbach fue de 0,71 y la armonía interjueces obtuvo un índice de Kappa moderado y bueno en la mayoría de los ítems (k=0,4-0,81) excepto en "lengua y encía" (k=0,33-0,37). La validez concurrente con la escala de la mucositis de la OMS fue aceptable (r=0,458). Todas las enfermeras (n=6) consideraron que la escala era fácil de entender y útil en la práctica clínica. Los pacientes dijeron que no les pareció incómoda la valoración de la boca con la escala. Conclusiones: La versión española de la OAG es un instrumento válido y fiable en pacientes con cáncer. Es una escala fácil de usar en la práctica clínica y bien aceptada por los pacientes (AU)

Background: The Oral Assessment Guide (OAG) is a widely used tool designed for evaluating problems of oral mucous in cancer patients, but it has not been validated in Spanish. The aim of this work is to translate and validate into Spanish the scale of the OAG designed by Eilers. Method: The translation process was carried out using the method of back-translation by bilingual translators. The study was carried out with cancer patients, both outpatient and inpatients, of the Hematology/Oncology Department and with oncology nurses. The following psychometric properties of the OAG were evaluated: internal consistency, concurrent validity with WHO’s mucositis scale, interjudge agreement between two different nurses. The perception of patients and nurses on the use of the OAG was also assessed. Results: An adequate Spanish version of the OAG was obtained. All the participants (n=40) completed the study. Internal consistency measured by Cronbach’s alpha was 0.71 and interjudge agreement obtained a moderate to good Kappa index in the majority of items (k=0.4-0.81), except in "tongue and gums" (k=0.33-0.37). Concurrent validity with WHO mucositis scale was acceptable (r=0.458). All the nurses (n=6) considered that the scale was easy to understand and useful in clinical practice. The patients said that oral evaluation with the scale did not cause them discomfort. Conclusions: The Spanish version of the OAG is a valid and reliable instrument in cancer patients. It is a scale that is easy to use in clinical practice and is well accepted by patients (AU)

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Myxococcus xanthus is a member of the Myxococcales order within the deltaproteobacterial subdivision. Here, we report the whole-genome shotgun sequence of the type IV pilus (T4P) defective strain DZF1, which includes many genes found in strain DZ2 but absent from strain DK1622.

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Myxococcus xanthus is a member of the Myxococcales order within the Deltaproteobacteria subdivision. The myxobacteria reside in soil, have relatively large genomes, and display complex life cycles. Here, we report the whole-genome shotgun sequence of strain DZ2, which includes unique genes not found previously in strain DK1622.

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Myxococcus xanthus utilizes two distinct motility systems for movement (gliding) on solid surfaces: adventurous motility (A-motility) and social motility (S-motility). Both systems are regulated by the Frz signal transduction pathway, which controls cell reversals required for directed motility and fruiting body formation. The Frz chemosensory system, unlike the Escherichia coli chemotaxis system, contains proteins with multiple response regulator domains: FrzE, a CheA-CheY hybrid protein, and FrzZ, a CheY-CheY hybrid protein. Previously, the CheY domain of FrzE was hypothesized to act as the response regulator output of the Frz system. In this study, using a genetic suppressor screen, we identified FrzZ and showed FrzZ is epistatic to FrzE, demonstrating that FrzZ is the principal output component of the pathway. We constructed M. xanthus point mutations in the phosphoaccepting aspartate residues of FrzZ and demonstrated the respective roles of these residues in group and single cell motility. We also performed in vitro assays and showed rapid phosphotransfer between the CheA domain of FrzE and each of the CheY domains of FrzZ. These experiments showed that FrzZ plays a direct role as an output of the Frz chemosensory pathway and that both CheY domains of FrzZ are functional.

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The Frz chemosensory system controls directed motility in Myxococcus xanthus by regulating cellular reversal frequency. M. xanthus requires the Frz system for vegetative swarming on rich media and for cellular aggregation during fruiting body formation on starvation media. The Frz signal transduction pathway is formed by proteins that share homology with chemotaxis proteins from enteric bacteria, which are encoded in the frzA-F putative operon and the divergently transcribed frzZ gene. FrzCD, the Frz system chemoreceptor, contains a conserved C-terminal module present in methyl-accepting chemotaxis proteins (MCPs); but, in contrast to most MCPs, FrzCD is localized in the cytoplasm and the N-terminal region of FrzCD does not contain transmembrane or sensing domains, or even a linker region. Previous work on the Frz system was limited by the unavailability of deletion strains. To understand better how the Frz system functions, we generated a series of in-frame deletions in each of the frz genes as well as regions encoding the N-terminal portion of FrzCD. Analysis of mutants containing these deletions showed that FrzCD (MCP), FrzA (CheW) and FrzE (CheA-CheY) control vegetative swarming, responses to repellents and directed movement during development, thus constituting the core components of the Frz pathway. FrzB (CheW), FrzF (CheR), FrzG (CheB) and FrzZ (CheY-CheY) are required for some but not all responses. Furthermore, deletion of approximately 25 amino acids from either end of the conserved C-terminal region of FrzCD results in a constitutive signalling state of FrzCD, which induces hyper-reversals with no net cell movement. Surprisingly, deletion of the N-terminal region of FrzCD shows only minor defects in swarming. Thus, signal input to the Frz system must be sensed by the conserved C-terminal module of FrzCD and not the usual N-terminal region. These results indicate an alternative mechanism for signal sensing with this cytoplasmic MCP.

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Myxococcus xanthus co-ordinates cell movement during its complex life cycle using multiple chemotaxis-like signal transduction pathways. These pathways regulate both type IV pilus-mediated social (S) motility and adventurous (A) motility. During a search for new chemoreceptors, we identified the che4 operon, which encodes homologues to a MCP (methyl-accepting chemotaxis protein), two CheWs, a hybrid CheA-CheY, a response regulator and a CheR. Deletion of the che4 operon did not cause swarming or developmental defects in either the wild-type (A(+)S(+)) strain or in a strain sustaining only A motility (A(+)S(-)). However, in a strain displaying only S motility (A(-)S(+)), deletion of the che4 operon or the gene encoding the response regulator, cheY4, caused enhanced vegetative swarming and prevented aggregation and sporulation. In contrast, deletion of mcp4 caused reduced vegetative swarming and enhanced development compared with the parent strain. Single-cell analysis of the motility of the A(-)S(+) parent strain revealed a previously unknown inverse correlation between velocity and reversal frequency. Thus, cells that moved at higher velocities showed a reduced reversal frequency. This co-ordination of reversal frequency and velocity was lost in the mcp4 and cheY4 mutants. The structural components of the S motility apparatus were unaffected in the che4 mutants, suggesting that the Che4 system affects reversal frequency of cells by modulating the function of the type IV pilus.

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A gene, xyl4, whose predicted amino acid sequence shows significant homology with family 11 xylanases, was identified from the tomato vascular wilt fungus Fusarium oxysporum f. sp. lycopersici. Expression of xyl4 is induced on oat spelt xylan as the carbon source, subject to carbon catabolite repression and preferentially expressed at alkaline ambient pH. Transcript levels of xyl4 on an inducing carbon source are differentially regulated by the nature and concentration of the nitrogen source. As shown by RT-PCR, xyl4 is expressed by F. oxysporum during the entire cycle of infection on tomato plants. Targeted inactivation of xyl4 and of xyl3, a previously identified gene of F. oxysporum f. sp. lycopersici encoding a family 10 xylanase, had no detectable effect on virulence on tomato plants, demonstrating that both genes are not essential for pathogenicity.

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A gene, xyl5, was identified from the tomato vascular wilt fungus Fusarium oxysporum f.sp. lycopersici, whose predicted amino acid sequence shows significant homology with family 11 xylanases. Expression of xyl5 was detected during growth both on xylan and cellulose substrates as carbon sources and on tomato vascular tissue. RT-PCR analysis revealed the presence of two different transcript sizes, resulting from differential splicing of the third intron. The 3'-untranslated region of the xyl5 transcript contained a region of homology to cellulose-binding domains, suggesting that such a domain may have been part of an ancestral XYL5 version. As shown by RT-PCR, xyl5 is expressed by F. oxysporum exclusively during the initial stages of infection in tomato roots. Targeted inactivation of xyl5 had no detectable effect on virulence.

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Fusarium oxysporum invades its host plants through the roots and colonizes the vascular system. It produces a great variety of cell-wall degrading enzymes (CWDE), such as cellulases, xylanases, pectinases and proteases. Our group has purified and characterized an endopolygalacturonase (PG1), two exopolygalacturonases (PG2 and PG3), an endoxylanase (XYL1) and an endo pectatelyase (PL1). We have isolated the following CWDE-encoding genes: pg1, pgx4, pg5, xyl2, xyl3, prt1 and pl1. Gene expression in different culture conditions has been determined by Northern analysis. The occurrence of these genes in different formae speciales has been analyzed by Southern analysis and PCR. All these genes are expressed during different stages of the interaction with the host plant indicating a possible role in pathogenesis. At present, targeted gene disruption is being carried out, in order to determine the role of each gene in the pathogenicity process.

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An active transposable element, Folyt1, has been isolated from the tomato pathogen Fusarium oxysporum f. sp. lycopersici as an insertion sequence within the coding region of the nitrate reductase gene (nit 1) in two independent mutants (CO66 and CO108). Folyt1 was 2615 bp in length and contained 9-bp imperfect inverted terminal repeats (ITRs) and 8 bp duplicated at the target site upon insertion. The element contained a long open reading frame interrupted by a single putative intron. The predicted amino acid sequence showed similarity to conserved domains of transposases from hobo, Ac, and Tam3 elements, which belong to the hAT family. The excision frequency of Folyt1 was determined to be less than 10(-5) in both mutants. These events restored the nit 1 wild-type allele without leaving footprints in all the revertants of strain CO66. Nevertheless, some revertants of strain CO108 showed a point mutation footprint at the target sequence. Expression of the Folyt1 transposase was detected by Northern analysis as a 2.1-kb transcript. The element exists in about 10 copies per genome in F. oxysporum f. sp. lycopersici and appears to be widely distributed among different formae speciales of F. oxysporum.

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In mammals, sex determination is controlled by the Y-linked gene SRY. Although SRY is male-specific in most eutherian and marsupial species, with a single copy on the Y chromosome, several rodent species have multiple Y-linked copies of SRY, and two mole-vole species of the genus Ellobius determine sex without the Y chromosome or the SRY gene. We searched for homologs of SRY in three vole species of the genus Microtus and concluded that this gene is not male-specific in M. cabrerae, as it is present in multiple, polymorphic copies in both males and females. In contrast, SRY is male-specific in the related species M. agrestis and M. nivalis. Up to 15 different partial sequences of the SRY gene were found in M. cabrerae. Southern blots suggest that most of the extra copies of SRY are X-linked. One of the copies observed only in males has a sequence identical to that of the SRY gene in M. agrestis and may represent a functional copy of the gene in this species. The rest are probably nonfunctional pseudogenes.

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SV40 based shuttle vectors able to be packaged as pseudovirions have been used either as naked DNA or as pseudovirus to analyse the mutation frequency and the UV-induced mutation spectra obtained after transfection or infection of COS7 monkey cells. The frequency of supF spontaneous mutants was similar whatever the state of the vector, indicating that the transfection step is not responsible for the high spontaneous mutation frequency when using shuttle vectors. Nevertheless the UV-induced mutation frequency of the supF gene was higher when transfected DNA was replicated into COS7 cells than when pseudovirus infection was performed. The UV induced mutation spectra was basically similar in both situations but a new hot-spot at nucleotide 110 was obtained after pseudovirus infection. UV-pretreated and control COS7 cells were infected with untreated or UV-damaged pi SVPC7 shuttle virus and the survival and the supF mutation frequency were analysed in the progeny. The survival of UV-damaged pseudovirus replicated in 10 J/m2 UV-pretreated cells was 2-fold higher than in untreated cells. This increase in the survival was accompanied by a slight enhancement in the number of supF mutants.

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The hepatitis B virus surface antigen (HBsAg) gene, under control of the inducible mouse metallothionein I gene promoter, was inserted in an expression vector based on the Epstein-Barr virus (EBV). This vector was introduced into human cells by DNA transfection and clones were selected for their resistance to hygromycin B. The recombinant EBV vector replicates efficiently as an episome in human cells and approximately six copies per cell were found in one clone of hygromycin-B-resistant cells. These cells produce high levels of HBsAg in the presence of metals. The protein is mainly found in the cell medium, suggesting that the HBsAg is secreted from the cells.

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We studied the anatomical, histological, and genetic features of the sexual tract in four European mole species of the genus Talpa (Insectivora, mammalia): T. occidentalis, T. europaea, T. romana, and T. stankovici. All XY individuals had a normal male phenotype, whereas all XX individuals in all four species had features that identified them as intersexes. These individuals were nonetheless presumed to be functionally fertile females. Intersexuality was manifested mainly as gonadal hermaphroditism, with all females possessing bilateral ovotestes. The gonads were composed of a small portion of histologically normal ovarian tissue and a variably sized, generally large mass of disgenetic testicular tissue, accompanied by a small, rudimentary epididymis. The rest of the sexual tract was typically female, including oviducts, uterus, and vagina of normal appearance. Polymerase chain reaction (PCR) and Southern blotting analyses showed that the mammalian testis-determining gene SRY is present in males but not in females. Part of the conserved sequence of the mole SRY gene was cloned and sequenced after PCR amplification in two of the four mole species (T. occidentalis from Spain and T. romana from Italy). Sequences were identical in these two species and were very similar to those of the human and mouse SRY gene. Our findings constitute the first evidence of the existence of a genus-specific case of true hermaphroditism, probably due to a very ancient mutation that fixed in populations of the ancestral species from which contemporary moles evolved. The possible nature of this mutation is discussed with regard to the cytologic, histologic, and genetic features of the gonads in Talpa females.

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We describe the expression of the transcription factor GHF-1/PIT-1 in adult porcine adenohypophysis by a nonradioactive in situ hybridization (ISH) method using a digoxigenin-labeled cDNA probe corresponding to the entire coding region of rat GHF-1. GHF-1 transcripts were found in 71.7% of adenohypophyseal cells. We also report the simultaneous detection of GHF-1 mRNA and pituitary hormones by combined ISH and immunocytochemistry (IC) in dispersed adenohypophyseal cells, detected with an alkaline phosphatase-NBT/BCIP technique and with an immunoperoxidase-3-amino-9-ethylcarbazole (AEC) method, respectively. The combination of the two techniques neither abolished nor diminished their sensitivity or specificity. GHF-1 is expressed in all five of the cell types in the adult porcine adenohypophysis, showing that this method is suitable for simultaneous detection of transcripts and proteins at the single-cell level.

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We have previously reported the isolation of an Escherichia coli K12 mutant that is extremely sensitive to mutagenesis by low doses of ethylating agents. We now show by Southern analysis that the mutation involves a gross deletion covering at least the ogt and fnr genes and that no O6-alkylguanine-DNA-alkyltransferase activity is present in cell-free extracts of an ada::Tn10 derivative of these bacteria. Confirmation that sensitisation to ethylation-induced mutagenesis was attributable to ogt and not to any other loci covered by the deletion was obtained by constructing derivatives. Thus an ogt::kanr disruption mutation was introduced into the parental ogt+ bacteria, and the ogt::kanr mutation was then eliminated by cotransduction of ogt+ with the closely linked Tetr marker (zcj::Tn10). The delta(ogt-fnr) deletion or ogt::kanr disruption mutants were highly sensitive to ethyl methanesulphonate-induced mutagenesis, as measured by the induction of forward mutations to L-arabinose resistance (Arar). Furthermore, the number of Arar mutants increased linearly with dose, unlike the case in ogt+ bacteria, which had a threshold dose below which no mutants accumulated. Differences in mutability were even greater with propyl methanesulphonate. Overproduction of the ogt alkyltransferase from a multicopy plasmid reduced ethylmethanesulphonate-induced mutagenesis in the ogt- mutant strains and also methylmethanesulphonate mutagenesis in ada- bacteria. A sample of AB1157 obtained from the E. coli K12 genetic stock centre also had a deletion covering the ogt and fnr genes. Since such deletions greatly influence the mutagenic responses to alkylating agents, a survey of the presence of the ogt gene in the E. coli K12 strain being used is advisable.

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The supF gene of Escherichia coli has been widely used as a mutagenic target in several shuttle-vector plasmids. Mutations in this gene are usually screened by a colony colour assay based on the suppression of a lacZ amber mutation in an appropriate bacterial indicator strain. This screening method cannot measure the low mutation frequencies usually detected in prokaryotes, and therefore precludes the use of supF gene for studying mutational spectra in bacteria. In this paper we report the development of a simple method for the selection of supF forward mutations in shuttle-vector plasmids. The method has implied the construction of an araD- araC(Am) mutant strain (MBL50) of E.coli. The L-arabinose sensitivity caused by the accumulation of a toxic intermediate in araD- mutants is abolished in MBL50 because the araC(Am) mutation blocks the L-arabinose catabolic pathway. Strain MBL50 becomes sensitive to L-arabinose when transformed with a supF+ plasmid but remains resistant upon transformation with a supF- mutant. This new L-arabinose resistance selection method was able to detect supF- mutant fractions up to three orders of magnitude below those determined with the colony colour screening assay. The method was further validated by carrying out in vivo mutagenesis experiments with N-methyl-N-nitrosourea (MNU) and a shuttle-vector-bearing strain (UC2109) completely defective in O6-methylguanine (O6meG) alkyltransferase repair capacity. The DNA sequence alterations of 22 independent supF- mutants induced by MNU were determined. All mutations were G:C-->A:T transitions in agreement with the predicted significance of the mispairing potential of the O6meG lesion. A preference for the sequence 5'-GG-3' was detected, revealing a 5'-flanking base influence. The accumulation of all 22 MNU-induced mutations in three sites of the supF genes might be related to the lack of O6meG alkyltransferase repair capacity of strain UC2109. The L-arabinose resistance method described in this paper allows rapid scoring and sequencing of forward mutations in the supF gene on shuttle-vectors, thus permitting its use as a genetic target for repair and mutagenesis studies in bacteria. Since shuttle-vectors replicate both in bacteria and mammalian cells, this method makes it possible to compare prokaryotic and eukaryotic mutational spectra.

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