Casos de Rabia Urbana en el Estado Zulia - Venezuela: Período 2007 - Julio 2013 / Cases of Urban Rabies in the State of Zulia, Venezuela: Period: 2007 - Julio 2013

La rabia es una zoonosis mortal y debido a su amplia distribución en el mundo, constituye un problema de relevancia en la salud pública; es una encefalomielitis viral aguda, transmitida por mordedura de un animal infectado. El Estado Zulia tiene carácter endémico y ha sido un problema de salud de alto impacto social. El objetivo de este estudio fue determinar los casos de rabia urbana en el Estado Zulia en el período 2007 - Julio 2013 e identificar su distribución según municipios y especies. La investigación fue de tipo descriptivo, se realizó revisión documental de los registros de la Coordinación Regional de Zoonosis del Estado Zulia del período estudiado. De las 2130 muestras diagnosticadas se observó una ocurrencia total de 117 (5,49%) casos de rabia urbana en los diferentes Municipios, de los cuales 116 se diagnosticaron en animales y 1 en humano, niña de 3 años perteneciente al municipio Maracaibo; la mayor ocurrencia fue en los municipios Maracaibo (42,73%) y Lagunillas (23,08%). Se recomienda coordinar actividades de extensión en comunidades basadas en la tenencia y manejo responsable de las mascotas, así como la necesidad de optimizar la vacunación como medida para eliminar el riesgo de infección.

Rabies is a lethal zoonosis, and due to its wide distribution around the world, it constitutes a relevant problem for the public health system. It is an acute viral encephalomyelitis, transmitted by the bite of an infected animal. Rabies is endemic in the State of Zulia and has been a health problem of high social impact. The objective of this study was to determine the cases of urban rabies in the State of Zulia from 2007 to July 2013 and to identify its distribution according to municipalities and species. The research is descriptive; a documentary review of records from the Regional Zoonosis Coordination of the State of Zulia was carried out for the period under study. From the 2130 diagnosed samples, a total occurrence of 117 (5.49%) cases of urban rabies was found among the different municipalities; 116 of these cases were diagnosed in animals and one in a human being, a three-year-old girl from the Maracaibo Municipality. The highest occurrence was in the municipalities of Maracaibo (42.73%) and Lagunillas (23.08%). The study recommends coordinating extension activities in communities, based on responsible pet possession and handling as well as the need to optimize vaccination procedures as a measure to eliminate the risk of infection.

Surface enhanced Raman scattering study of the antioxidant alkaloid boldine using prismatic silver nanoparticles.

Prismatic silver nanoparticles (PNps) were used in the surface enhanced Raman scattering (SERS) study of the antioxidant alkaloid boldine (5,6,6a,7-tetrahydro-1,10-dimethoxy-6-methyl-4H-dibenzo[de,g]quinoline-2,9-diol). Prismatic and quasi-spherical (QsNps) silver nanoparticles were synthesized and characterized by UV-Vis spectra, topographic profile (AFM) and zeta potential measurements. Raman and infrared (IR) spectra of the boldine were registered. Theoretical model calculations of the boldine onto the Ag surface predict a nearly coplanar orientation of the benzo[de]quinoline moiety and non-bonded interactions (electrostatic).

Prevalencia y epidemiología de Blastocystis sp. en dos comunidades del municipio Maracaibo-Estado Zulia / Prevalence and Epidemiology of Blastocystis Sp. In Two Communties of The Maracaibo Municipality, State of Zulia

Para determinar la prevalencia de Blastocystis sp. y su asociación con características epidemiológicas se realizó una investigación descriptiva en dos comunidades del Municipio Maracaibo del Estado Zulia. Para la recolección de datos se empleó una ficha epidemiológica; participaron 406 individuos seleccionados aleatoriamente realizándoseles a cada uno, un examen coproparasitológico directo con SSF-Lugol. Entre los estudiados predominaron los mayores de 18 años (72,1%) y el género femenino (51,4%). La prevalencia de Blastocystis sp. fue 38,9%, con mayor frecuencia de poliparasitismo (54,4%), identificándose Endolimax nana (36,1%) como especie comensal principalmente asociada, seguida de Giardia intestinalis (22,1%) entre los patógenos. Hubo asociación significativa (p<0.05) entre la prevalencia de la infección con el status de ocupación activa, hacinamiento, consumo de agua no tratada y ausencia de adecuadas condiciones para disponer y eliminar basura. Dichas variables mostraron valores OR 95% IC que evidencian su influencia como factores de riesgo, presentándose para el status de ocupación activa el mayor riesgo de infección (OR = 3,18). No se observó asociación significativa entre presencia de Blastocystis sp. con otras características epidemiológicas (p>0.05). Las limitaciones en los estándares de higiene comunal y personal son determinantes de la prevalencia de Blastocystis sp. en estas comunidades.

To determine the prevalence of Blastocystis sp. and its association with epidemiological characteristics, a cross-sectional study was conducted in two communities of the Maracaibo Municipality, State of Zulia. To collect data, an epidemiological record was used; 406 randomly selected individuals participated; for each one, a direct parasitological examination with SSF- Lugol was performed. Individuals over 18 years (72.1%) and females (51.4%) predominated. The overall prevalence of Blastocystis sp. infection was 38.9%; poly-parasitism predominated (54.4 %), identifying Endolimax nana (36.1%) as the most frequently associated commensal species, followed by Giardia intestinalis (22.1%), among the pathogens. There was significant association (p<0.05) between the prevalence of infection with active occupation status, overcrowding, untreated water consumption and lack of adequate conditions to dispose of and eliminate waste. These variables showed OR 95% CI values, which demonstrates their influence as risk factors, reporting the greatest risk of infection (OR=3.18) for the active occupation status. No significant association was noted between the presence of Blastocystis sp. and other epidemiological characteristics (p >0.05). Limitations in community and personal hygiene standards are determinants for the prevalence of Blastocystis sp. in these communities.

Assessment of food consumption, energy and protein intake in the meals offered in four Spanish nursing homes.

BACKGROUND/OBJECTIVE: The elderly, and especially those attending nursing homes, are at great risk from certain nutritional deficiencies. The aim of this study was to examine the percentage of energy wasted, energy and protein intake and percentage consumed of meal offered by a group of healthy institutionalized elderly in four nursing homes in Spain. DESIGN AND METHODS: This was a multicentre observational study of a sample of the institutionalized population over the age of 65. Our final sample comprised a total of 62 individuals. Dietary data were collected using double weight method for each meal during 21 days. We calculated the following consumption variables: percentage of food consumed (% food consumed) for each subject in each meal. We also calculated the energy intake (kcal/day), the wasted energy (kcal/day), the protein intake (g protein/ day) and the energy density (kcal/g meal) for each of the meals eaten. To analyse the overall differences we used analysis of variance test (ANOVA). The significance level used was 0.05 (p < 0.05). RESULTS: The largest meals were lunch (781 g/day [728.4, 833.6]) and dinner (653 g/day [612.1, 693.9]). The percentage of total consumption was 81.9% [79.3, 84.6]. The average energy consumption was 1,575.4 kcal/day [1,508.3, 1,642.6]. The percentage of caloric distribution varied depending on the center. The highest percentage of wasted food was found in the main meals. Forty four percent did not consume enough energy to meet the recommended intakes. Protein intake was 63.6 g protein / day [61.2, 66.1]. 12.5% of women and 4.55% of men did not consume the recommended intakes for the elderly. Breakfast and the bedtime snack had the highest energy density with 1.10 [0.9, 1.25] and 1.04 [0.9, 1.08] kcal/g food served respectively [Energy density]. DISCUSION/CONCLUSIONS: The best strategy for increasing the energy intake of the institutionalized elderly without raising the amount of food that is rejected may be to provide higher energy density foods in the same serving sizes.

[Frequency of chronic kidney disease among ambulatory patients with type 2 diabetes]. / Prevalencia y clasificación de enfermedad renal crónica en pacientes con diabetes mellitus tipo 2 en el centro comunitario de salud familiar Pantanosa, Frutillar.

BACKGROUND: Type 2 diabetes mellitus is the main cause of chronic kidney disease in developed countries. AIM: To study the prevalence of chronic kidney disease among adults with diabetes mellitus attended at a public primary health care clinic in southern Chile. MATERIAL AND METHODS: One hundred patients with type 2 diabetes mellitus, aged more than 15 years participated in this cross sectional study. Chronic kidney disease was defined as the presence of a urine albumin/creatinine ratio over 30 mg/g or an estimated glomerular filtration rate of less than 60 mL/min/1,73 m², detected in at least two opportunities, separated at least by three months. RESULTS: Thirty four percent of participants had chronic kidney disease (17% stage 1 or 2 and 17% stage 3). Thirty percent of participants had an abnormal urinary albumin/creatinine ratio. Halfof the patients with an estimated glomerular filtration rate below 60 mL/min/1,73 m², had a normal urinary albumin/creatinine ratio. CONCLUSIONS: The rates of chronic kidney disease in this group of diabetic patients are very similar to those reported elsewhere.

Assessing risk screening methods of malnutrition in geriatric patients: Mini Nutritional Assessment (MNA) versus Geriatric Nutritional Risk Index (GNRI).

INTRODUCTION: Elderly subjects are considered a vulnerable group and they have more risk of nutritional problems. The risk of malnutrition increases in hospitalized geriatric patients. OBJECTIVES: To compare the correlation between MNA and GNRI with anthropometric, biochemical and Barthel Index in hospitalized geriatric patients and to test the concordance between MNA and GNRI and between Mini Nutritional Assessment Short Form (MNA-SF) and MNA. METHODS: It was a cross-sectional study on a sample of 40 hospitalized geriatric patients. For determination nutritional status we used MNA and GNRI; we evaluated the correlation between this both test with biochemical and anthropometric parameters and functional questionnaires. We used Pearson's simple correlation model, oneway ANOVA and multiple logistic regression to evaluate the relationship between MNA and GNRI. RESULTS: According to MNA, 17 patients (42.5%) were malnourished and according to GNRI, 13 patients (32.5%) had high risk of nutritional complications. The concordance of MNA and GNRI was 39% and between MNA-SF and MNA was 81%. The most significant differences were detected in weight, BMI, arm and calf circumference and weight loss parameters. Barthel index was significantly different in both tests. The MNA and GRNI had significant correlations with albumin, total protein, transferring, arm and calf circumference, weight loss and BMI parameters. CONCLUSIONS: In conclusion, it would be reasonable to use GRNI in cases where MNA is not applicable, or even use GRNI as a complement to MNA in hospitalized elderly patients. There is no reason why they should be deemed incompatible, and patients could benefit from more effective nutritional intervention.

Assessment of food consumption, energy and protein intake in the meals offered in four Spanish nursing homes / Evaluación del consumo de alimentos, ingesta de proteínas y energía en las comidas ofrecidas en cuatro residencias geriátricas españolas

Background/objective: The elderly, and especially those attending nursing homes, are at great risk from certain nutritional deficiencies. The aim of this study was to examine the percentage of energy wasted, energy and protein intake and percentage consumed of meal offered by a group of healthy institutionalized elderly in four nursing homes in Spain. Design and methods: This was a multicentre observational study of a sample of the institutionalized population over the age of 65. Our final sample comprised a total of 62 individuals. Dietary data were collected using double weight method for each meal during 21 days. We calculated the following consumption variables: percentage of food consumed (% food consumed) for each subject in each meal. We also calculated the energy intake (kcal/day), the wasted energy (kcal/day), the protein intake (g protein/ day) and the energy density (kcal/g meal) for each of the meals eaten. To analyse the overall differences we used analysis of variance test (ANOVA). The significance level used was 0.05 (p < 0.05). Results: The largest meals were lunch (781 g/day [728.4, 833.6]) and dinner (653 g/day [612.1, 693.9]). The percentage of total consumption was 81.9% [79.3, 84.6]. The average energy consumption was 1,575.4 kcal/day [1,508.3, 1,642.6]. The percentage of caloric distribution varied depending on the center. The highest percentage of wasted food was found in the main meals. Forty four percent did not consume enough energy to meet the recommended intakes. Protein intake was 63.6 g protein / day [61.2, 66.1]. 12.5% of women and 4.55% of men did not consume the recommended intakes for the elderly. Breakfast and the bedtime snack had the highest energy density with 1.10 [0.9, 1.25] and 1.04 [0.9, 1.08] kcal/g food served respectively [Energy density]. Discusion/conclusions: The best strategy for increasing the energy intake of the institutionalized elderly without raising the amount of food that is rejected may be to provide higher energy density foods in the same serving sizes (AU)

Antecedentes/objetivos: Los ancianos, y especialmente los institucionalizados en residencias geriátricas, tiene un elevado riesgo de sufrir deficiencias nutricionales importantes. El objetivo de este estudio fue evaluar el porcentaje de comida consumida en cada ingesta así como la ingesta total energética y proteica en un grupo de ancianos sanos institucionalizados en cuatro residencias geriátricas de España. Métodos: Se llevó a cabo un estudio observacional multicéntrico en una muestra de población anciana (edad > 65 años) institucionalizada. La muestra final incluyó un total de 62 individuos sanos. Los datos de consumo se evaluaron mediante el método de registro de doble pesada para cada comida durante un período de 21 días consecutivos. Se calcularon las variables: porcentaje de consumo de alimentos (% ración consumida) para cada individuo en cada comida. También se calculó el consumo de energía (kcal/día), la energía desperdiciada (kcal/día), la ingesta de proteínas y la densidad calórica de las comidas (kcal/g ingesta). Para analizar las diferencias se llevó a cabo un análisis de la varianza (ANOVA). El nivel de significación usado fue de 0,05 (p < 0,05). Resultados: Las comidas más voluminosas fueron el almuerzo (781 g/día) [728,4-833,6] y la cena (653 g/día [612,1-693,9]. El porcentaje de consumo total fue del 81,9% [79,3-84,6]. El consumo de medio de energía fue de 1.575,4 kcal/día [1.508,3-1.642,6]. El porcentaje de distribución calórica varió en función de cada centro. El mayor porcentaje de desperdicio de alimentos fue en las comidas principales (almuerzo y cena). 44% de los ancianos no cubrían las recomendaciones energéticas establecidas. La ingesta de proteínas fue del 63,6 g proteína/día [61,266,1]. Un 12,5% de las mujeres y un 4,55 de los hombres no cubrieron las ingestas recomendadas de proteínas. Discusión/conclusiones: En vista de los resultados, probablemente una buena estrategia para mejorar el consumo de energía y nutrientes y reducir los porcentajes de comida desperdiciada entre los ancianos institucionalizados podría ser planificar comidas menos voluminosas y con una densidad energética y nutricional más elevada (AU)

Assessing risk screening methods of malnutrition in geriatric patients; Mini Nutritional Assessment (MNA) versus Geriatric Nutritional Risk Index (GNRI) / Evaluación de los métodos de cribaje de riesgo nutricional en pacientes geriátricos; Mini Nutritional Assessment (MNA) versus Geriatric Nutritional Risk Assessment (GNRI)

Introduction: Elderly subjects are considered a vulnerable group and they have more risk of nutritional problems. The risk of malnutrition increases in hospitalized geriatric patients. Objectives: To compare the correlation between MNA and GNRI with anthropometric, biochemical and Barthel Index in hospitalized geriatric patients and to test the concordance between MNA and GNRI and between Mini Nutritional Assessment Short Form (MNA-SF) and MNA. Methods: It was a cross-sectional study on a sample of 40 hospitalized geriatric patients. For determination nutritional status we used MNA and GNRI; we evaluated the correlation between this both test with biochemical and anthropometric parameters and functional questionnaires. We used Pearson's simple correlation model, oneway ANOVA and multiple logistic regression to evaluate the relationship between MNA and GNRI. Results: According to MNA, 17 patients (42.5%) were malnourished and according to GNRI, 13 patients (32.5%) had high risk of nutritional complications. The concordance of MNA and GNRI was 39% and between MNA-SF and MNA was 81%. The most significant differences were detected in weight, BMI, arm and calf circumference and weight loss parameters. Barthel index was significantly different in both tests. The MNA and GRNI had significant correlations with albumin, total protein, transferring, arm and calf circumference, weight loss and BMI parameters.Conclusions: In conclusion, it would be reasonable to use GRNI in cases where MNA is not applicable, or even use GRNI as a complement to MNA in hospitalized elderly patients. There is no reason why they should be deemed incompatible, and patients could benefit from more effective nutritional intervention (AU)

Antecedentes: La población anciana esta considerada como un colectivo vulnerable a sufrir problemas nutricionales. Entre estos, los ancianos hospitalizados tienen aun un mayor riesgo a sufrir malnutrición. Objetivos: Los objetivos de este estudio fueron comparar el grado de correlación entre dos índices de cribaje nutricional, el Mini Nutritional Assessment (MNA) y el Geriatric Nutritional Risk Index (GNRI) con los parámetros antropométricos, bioquímicos, el índice de Barthel y ciertas patologías relacionadas con el estado nutricional (infecciones y úlceras por presión). Metodología: Se llevó a cabo un estudio transversal en una muestra de 40 pacientes hospitalizados en una unidad geriátrica de agudos. Para la determinación del estado nutricional se usaron los índices del MNA y el GNRI. Se evaluó la correlación entre los parámetros bioquímicos, antropométricos, parámetros funcionales y problemas nutricionales relacionados con la malnutrición (úlceras por presión y infecciones). Para el modelo de correlación, se utilizó el grado de correlación de Pearson; para estudiar la relación entre los índices nutricionales (MNA y GNRI) y los diferentes parámetros se utilizó un análisis de la variancia y un modelo de regresión logística. Resultados: De acuerdo con el MNA, 17 pacientes (42,5%) estaban desnutridos y de acuerdo con GNRI, 13 pacientes (32,5%) tenían alto riesgo de complicaciones nutricionales. La concordancia de la MNA y la GNRI fue del 39% y entre MNA-SF y MNA fue de 81%. Las diferencias más significativas se detectaron en el peso, el IMC, el brazo y circunferencia de la pantorrilla y los parámetros de pérdida de peso. El MNA y GRNI mostró correlaciones significativas con la albúmina, proteínas totales, la transferencia, la circunferencia del brazo y de la pantorrilla, con el % de pérdida de peso y el índice de masa corporal (IMC). Los pacientes malnutridos según el MNA y los pacientes con riesgo elevado según el GNRI tenían mayor riesgo de sufrir úlceras por presión. Conclusiones: en conclusión, sería razonable utilizar el GNRI en los casos en que el MNA no fuera aplicable, o incluso utilizar GNRI como complemento al MNA en pacientes ancianos hospitalizados. No hay ninguna razón por la cual se deban considerar incompatibles, y los pacientes podrían beneficiarse de una intervención nutricional más efectiva (AU)

Prevalencia y clasificación de enfermedad renal crónica en pacientes con diabetes mellitus tipo 2 en el centro comunitario de salud familiar Pantanosa, Frutillar / Frequency of chronic kidney disease among ambulatory patients with type 2 diabetes

Background: Type 2 diabetes mellitus is the main cause of chronic kidney disease in developed countries. Aim: To study the prevalence of chronic kidney disease among adults with diabetes mellitus attended at a public primary health care clinic in southern Chile. Material and Methods: One hundred patients with type 2 diabetes mellitus, aged more than 15 years participated in this cross sectional study. Chronic kidney disease was defined as the presence of a urine albumin/creatinine ratio over 30 mg/g or an estimated glomerular filtration rate of less than 60 mL/min/1,73 m², detected in at least two opportunities, separated at least by three months. Results: Thirty four percent of participants had chronic kidney disease (17% stage 1 or 2 and 17% stage 3). Thirty percent of participants had an abnormal urinary albumin/creatinine ratio. Halfof the patients with an estimated glomerular filtration rate below 60 mL/min/1,73 m², had a normal urinary albumin/creatinine ratio. Conclusions: The rates of chronic kidney disease in this group of diabetic patients are very similar to those reported elsewhere.

Puente miocardico: caso clínico y revisión bibliografica / Myocardial bridge: clinical case and review of literature

Se presenta el caso de un paciente con ausencia de factores de riesgo cardiovascular que fue ingresado a la Unidad Coronaria del Hospital San Juan de Dios por un cuadro característico de angina inestable, sin ECG categórico de isquemia ni exámenes que la ratificaran. El enfermo fue sometido a cateterismo cardíaco, el que reveló la presencia de un puente muscular en la porción media de la arteria descendiente anterior. El paciente evolucionó en forma satisfactoria con tratamiento médico y en controles posteriores no ha vuelto a presentar sintomatología. Se aprovecha el caso observado para revisar la bibliografía pertinente. Esta revela que los puentes miocárdicos no son tan excepcional como se cree y que pueden explicar casos de angor en coronarias normales.

Efficacy of acupuncture in asthma: systematic review and meta-analysis of published data from 11 randomised controlled trials.

Contradictory results from randomised controlled trials of acupuncture in asthma suggest both a beneficial and detrimental effect. The authors conducted a formal systematic review and meta-analysis of all randomised clinical trials in the published literature that have compared acupuncture at real and placebo points in asthma patients. The authors searched for trials published in the period 1970-2000. Trials had to measure at least one of the following objective outcomes: peak expiratory flow rate, forced expiratory volume in one second (FEV1) and forced vital capacity. Estimates of the standarised mean difference, between acupuncture and placebo were computed for each trial and combined to estimate the overall effect. Hetereogeneity was investigated in terms of the characteristics of the individual studies. Twelve trials met the inclusion criteria but data from one could not be obtained. Individual patient data were available in only three. Standardised differences between means ranging from 0.071 to 0.133, in favour of acupuncture, were obtained. The overall effect was not conventionally significant and it corresponds to an approximate difference in FEV1 means of 1.7. After exploring hetereogenenity, it was found that studies where bronchoconstriction was induced during the experiment showed a conventionally significant effect. This meta-analysis did not find evidence of an effect of acupuncture in reducing asthma. However, the meta-analysis was limited by shortcomings of the individual trials, in terms of sample size, missing information, adjustment of baseline characteristics and a possible bias against acupuncture introduced by the use of placebo points that may not be completely inactive. There was a suggestion of preferential publication of trials in favour of acupuncture. There is an obvious need to conduct a full-scale randomised clinical trial addressing these limitations and the prognostic value of the aetiology of the disease.

Evidence for an ancient chromosomal duplication in Arabidopsis thaliana by sequencing and analyzing a 400-kb contig at the APETALA2 locus on chromosome 4.

As part of the European Scientists Sequencing Arabidopsis program, a contiguous region (396607 bp) located on chromosome 4 around the APETALA2 gene was sequenced. Analysis of the sequence and comparison to public databases predicts 103 genes in this area, which represents a gene density of one gene per 3.85 kb. Almost half of the genes show no significant homology to known database entries. In addition, the first 45 kb of the contig, which covers 11 genes, is similar to a region on chromosome 2, as far as coding sequences are concerned. This observation indicates that ancient duplications of large pieces of DNA have occurred in Arabidopsis.

Gene discovery in the wood-forming tissues of poplar: analysis of 5, 692 expressed sequence tags.

A rapidly growing area of genome research is the generation of expressed sequence tags (ESTs) in which large numbers of randomly selected cDNA clones are partially sequenced. The collection of ESTs reflects the level and complexity of gene expression in the sampled tissue. To date, the majority of plant ESTs are from nonwoody plants such as Arabidopsis, Brassica, maize, and rice. Here, we present a large-scale production of ESTs from the wood-forming tissues of two poplars, Populus tremula L. x tremuloides Michx. and Populus trichocarpa 'Trichobel.' The 5,692 ESTs analyzed represented a total of 3,719 unique transcripts for the two cDNA libraries. Putative functions could be assigned to 2,245 of these transcripts that corresponded to 820 protein functions. Of specific interest to forest biotechnology are the 4% of ESTs involved in various processes of cell wall formation, such as lignin and cellulose synthesis, 5% similar to developmental regulators and members of known signal transduction pathways, and 2% involved in hormone biosynthesis. An additional 12% of the ESTs showed no significant similarity to any other DNA or protein sequences in existing databases. The absence of these sequences from public databases may indicate a specific role for these proteins in wood formation. The cDNA libraries and the accompanying database are valuable resources for forest research directed toward understanding the genetic control of wood formation and future endeavors to modify wood and fiber properties for industrial use.

Sequence analysis of a 40-kb Arabidopsis thaliana genomic region located at the top of chromosome 1.

As a contribution to the European Scientists Sequencing Arabidopsis (BIOTECH ESSA) project, a contig of almost 40kb has been sequenced at the extreme top of chromosome 1, around the Arabidopsis thaliana gene coding for a member of the 1-aminocyclopropane-1-carboxylate synthesis gene family. The region contains, besides the ACS1 gene itself, 10 putative genes, all new for Arabidopsis. Among these are three genes encoding kinases, a late embryogenesis-abundant protein, a MADS box-containing protein, a dehydrogenase, and a Myb-related transcription factor. In addition, six cDNAs have been sequenced that correspond to this region.

Analysis of 1.9 Mb of contiguous sequence from chromosome 4 of Arabidopsis thaliana.

The plant Arabidopsis thaliana (Arabidopsis) has become an important model species for the study of many aspects of plant biology. The relatively small size of the nuclear genome and the availability of extensive physical maps of the five chromosomes provide a feasible basis for initiating sequencing of the five chromosomes. The YAC (yeast artificial chromosome)-based physical map of chromosome 4 was used to construct a sequence-ready map of cosmid and BAC (bacterial artificial chromosome) clones covering a 1.9-megabase (Mb) contiguous region, and the sequence of this region is reported here. Analysis of the sequence revealed an average gene density of one gene every 4.8 kilobases (kb), and 54% of the predicted genes had significant similarity to known genes. Other interesting features were found, such as the sequence of a disease-resistance gene locus, the distribution of retroelements, the frequent occurrence of clustered gene families, and the sequence of several classes of genes not previously encountered in plants.

The expression of the salt-responsive gene salT from rice is regulated by hormonal and developmental cues.

The expression pattern of the salT gene was analyzed in different cell types and organs of rice (Oryza sativa L.) in response to saline and hormonal treatments to obtain detailed information on the physiological cues controlling gene expression. Gel blot analysis of RNA and in-situ hybridization performed on seedlings grown for 10 ds in the presence of 1% NaCl revealed that salT was expressed mainly in the younger tissues of the plant. In contrast, 6-week-old plants exhibited maximal salT mRNA accumulation in sheaths of older leaves. In addition, salT was normally expressed in rapidly dividing suspension-cultured cells, but not in quiescent ones. Altogether, these results may indicate that salT expression in each region of the plant is dependent on the metabolic activity of the cells as well as on whether or not they are stressed. The effects of two growth regulators, abscisic acid (ABA) and gibberellic acid, were investigated in combination with the effects of NaCl. Gibberellic acid had a synergistic effect on the induction of the salT gene when combined with 0.5% NaCl, but did not induce salT on its own. At 10 microM, ABA induced salT both in the absence of NaCl and in its presence. Whereas 1 microM ABA acted additively with NaCl to induce gene expression, 5 microM ABA with NaCl was only as effective as NaCl alone. This may indicate that the two stimuli act independently and possibly through antagonistic signal transduction pathways.

Sequence analysis of a 24-kb contiguous genomic region at the Arabidopsis thaliana PFL locus on chromosome 1.

As part of the European Union program of European Scientist Sequencing Arabidopsis (ESSA), the DNA sequence of a 24.053-bp insert of cosmid clone CC17J13 was determined. The cosmid is located on chromosome 1 at the PFL locus (position 30 cM). Analysis of the sequence and comparison to public databases predicts seven genes in this area, thus approximately one gene every 3.3 kb. Three cDNAs corresponding to genes in this region were also sequenced. The homologies and/or possible functions of the (putative) genes are discussed. Proteins encoded by genes in this region include a polyadenylate-binding protein (PAB-3) and a GTP-binding protein (Rab7) as well as a novel protein, possibly involved in double-stranded RNA unwinding and apoptosis. Intriguingly, the gene encoding the PAB-3 protein, which is very specifically expressed, is flanked by putative matrix attachment regions.

The AP2 domain of APETALA2 defines a large new family of DNA binding proteins in Arabidopsis.

APETALA2 (AP2) plays an important role in the control of Arabidopsis flower and seed development and encodes a putative transcription factor that is distinguished by a novel DNA binding motif referred to as the AP2 domain. In this study we show that the AP2 domain containing or RAP2 (related to AP2) family of proteins is encoded by a minimum of 12 genes in Arabidopsis. The RAP2 genes encode two classes of proteins, AP2-like and EREBP-like, that are defined by the number of AP2 domains in each polypeptide as well as by two sequence motifs referred to as the YRG and RAYD elements that are located within each AP2 domain. RAP2 genes are differentially expressed in flower, leaf, inflorescence stem, and root. Moreover, the expression of at least three RAP2 genes in vegetative tissues are controlled by AP2. Thus, unlike other floral homeotic genes, AP2 is active during both reproductive and vegetative development.