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Tomato brown rugose fruit virus (ToBRFV) has become a cause of great concern in the global tomato agro-industry since its first report in Israel in 2014. Global tomato production is affected by ToBRFV, and management practices are being evaluated. We tested seed lots from international producers as well as greenhouse substrates and water wells as possible sources of virus contamination. We identified a second introduction of ToBRFV in Mexico by a strain closely resembling isolates from the Netherlands and the Middle East. ToBRFV was detected by RT-PCR in seed coats and epicotyls (from commercial seeds and seedlings obtained from infected tomato plants), indicating a transmission rate of 9%. Virus-like particles (VLPs) were found in wells used for irrigation in greenhouses, but these exhibited low infectivity. These findings suggest that water sources could serve as ToBRFV reservoirs. We evaluated four chemical and six thermal methods for sanitizing substrates, plasticware, and other greenhouse utensils, using detached leaf bioassays in Nicotiana rugosa. The most effective chemical sanitization method was treatment with glutaraldehyde plus quaternary ammonium salts and pentapotassium salts. The most effective heat treatment was at 92°C for 30 minutes, which inactivated the virus. Tomato producers could implement these sanitization methods to control ToBRFV.

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Transcription factors are important regulators of gene expression. They can orchestrate the activation or repression of hundreds or thousands of genes and control diverse processes in a coordinated way. This work explores the effect of a master regulator of plant development, BOLITA (BOL), in plant metabolism, with a special focus on specialized metabolism. For this, we used an Arabidopsis thaliana line in which the transcription factor activity can be induced. Fingerprinting metabolomic analyses of whole plantlets were performed at different times after induction. After 96 h, all induced replicas clustered as a single group, in contrast with all controls which did not cluster. Metabolomic analyses of shoot and root tissues enabled the putative identification of differentially accumulated metabolites in each tissue. Finally, the analysis of global gene expression in induced vs. non-induced root samples, together with enrichment analyses, allowed the identification of enriched metabolic pathways among the differentially expressed genes and accumulated metabolites after the induction. We concluded that the induction of BOL activity can modify the Arabidopsis metabolome. Future work should investigate whether its action is direct or indirect, and the implications of the metabolic changes for development regulation and bioprospection.

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The nymphs and adults of Triatoma infestans spend much of their time aggregated among themselves within narrow and dark shelters. The search for a suitable shelter depends in part on the recognition of chemical signals coming from the feces and the cuticle of the other individuals who use the refuge. The aim of this study was determine the possible interaction between the chemical signals associated to the feces and to the cuticle of T. infestans. The results showed that the insects remained significantly more time on the feces that had contact with legs and the feces plus footprints than feces or footprints alone, demonstrating the interaction between evaluated signals. These results demonstrates also that feces extracted a chemical stimulus from the legs. Understanding the interaction feces-legs as an interaction feces-cuticle of legs, the results suggest that the feces could extract some cuticular compound with activity on the behavior of the insects. This is the first report of the interaction between the two aggregation signals recognized in T. infestans and of the increase in the behavioral response of insects exposed to feces that had contact with a cuticular structure.

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BACKGROUND: The Triatoma phyllosoma complex of Trypanosoma cruzi vectors (Triatominae: Reduviidae) is distributed in both Neotropical and Nearctic bioregions of Mexico. METHODS: Volatile organic compounds emitted by disturbed Triatoma longipennis, Triatoma pallidipennis and Triatoma phyllosoma, and from their Brindley's and metasternal glands, were identified using solid-phase microextraction coupled with gas chromatography-mass spectrometry. RESULTS: Disturbed bugs and the metasternal glands from T. phyllosoma released or had significantly fewer compounds than T. longipennis and T. pallidipennis. Isobutyric acid was the most abundant compound secreted by disturbed bugs of the three species, while Brindley's glands of all species produced another four compounds: propanoic acid, isobutyric acid, pentyl butanoate, and 2-methyl hexanoic acid. Two novel compounds, both rose oxide isomers, were produced in MGs and released only by disturbed females of all three species, making this the first report in Triatominae of these monoterpenes. The principal compound in MGs of both sexes of T. longipennis and T. phyllosoma was 3-methyl-2-hexanone, while cis-rose oxide was the principal compound in T. pallidipennis females. The major components in male effluvia of T. pallidipennis were 2-decanol and 3-methyl-2-hexanone. CONCLUSION: Discriminant analysis of volatile organic compounds was significant, separating the three species and was consistent with morphological and genetic evidence for species distinctions within the complex.

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OBJECTIVE: We report on two rare Xq rearrangements, namely a t(X;9)(q24;q12) found in a mildly-affected girl (Patient 1) and a rea(X)dup q concomitant with a rob(14;21)mat in a Down syndrome girl (Patient 2). CASE REPORT: Both rearrangements were characterized by banding techniques [Giemsa (G), constitutive heterochromatin (C), and bromodeoxyuridine (BrdU) pulse], fluorescence in situ hybridization (FISH) assays, human androgen receptor (HUMAR) assays, and microarray analyses. Patient 1 had a t(X;9)(q24;q12)dn. Patient 2 had a de novo rea(X)(qter→q23 or q24::p11.2→qter) concomitant with an unbalanced rob(14;21)mat. X-Inactivation studies in metaphases and DNA revealed a fully skewed inactivation: the normal homolog was silenced in Patient 1 and the rea(X) in Patient 2. Both rearranged X chromosomes were of paternal descent. Microarray analyses revealed no imbalances in Patient 1 whereas loss of Xp (∼52 Mb) and duplication of Xq (∼44 Mb) and 21q were confirmed in Patient 2. CONCLUSION: Our observations further document the cytogenetic heterogeneity and predominant paternal origin of certain de novo X-chromosome rearrangements.

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Malignant myoepitheliomas (MM) (myoepithelial carcinomas) are rare tumors representing <1% of salivary gland tumors. They are characterized as being locally aggressive. Rarely do they present distant metastases; however, when they do metastasize the sites most affected are the lungs, liver, pleura, peritoneum and skin. They may originate de novo in a pleomorphic adenoma or a benign myoepithelioma. We report the case of a patient with a submucosal lesion of the soft palate measuring ∼4cm×3cm. The patient underwent transoral resection with a microscope and CO2 laser. Histopathological report was MM originating in a pleomorphic adenoma. Management of this neoplasm is controversial. Myoepithelial carcinoma is a rare neoplasm whose diagnosis includes immunohistochemical (IHC) studies. Surgery is the cornerstone of treatment. Management with laser surgery may preserve the function of the soft palate without deterioration of the quality of life in these patients.

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BACKGROUND AND PURPOSE: The Government of Jamaica, through the Ministry of Health and other ministries, assisted by international funding agencies and members of non-governmental organizations, has diligently led the charge to reduce the incidence of HIV and AIDS in Jamaica. Yet, the continued escalation in the infection rate attested to the need for education towards the reduction of stigma and discrimination, factors that fuel the spread of the virus. Significant efforts were made to woo corporations in Jamaica to redouble their efforts and provide resources to address the continued escalation of the AIDS epidemic in Jamaica. Scotiabank Jamaica responded with a unique educational initiative. METHODS: The Scotiabank National Primary Schools HIV and AIDS Debating Competition in 2006- 2007 was conducted over a seven-month period. It was opened to primary-level, government and private institutions islandwide. RESULTS: A total of 91 institutions competed with each other, debating 16 moots (ie topics) in 417 debates from the first preliminary rounds through to the final. Moots reflected curricular and extracurricular concerns, emphasized the values of compassion, healthy lifestyles, critical thinking and child rights; they also sent messages of anti-discrimination, and parental and community responsibilities. Whereas communication between the organizers and the schools was sometimes challenging, schools subscribed to the activity (debates) for the awareness it brought and for the potential for developing students. Attempts were also made to raise awareness among teachers, parents and the general community. CONCLUSION: Feedback at the end acclaimed the debates as a valuable strategy for building awareness as well as development of student potential and unity around a common cause.

ANTECEDENTES Y PROPÓSITO: El Gobierno de Jamaica, a través del Ministerio de Salud y otros ministerios. Con la asistencia de agencias de fondos internacionales y miembros de organizaciones no gubernamentales, ha centrado diligentemente todos sus esfuerzos en reducir la incidencia del VIH y el SIDA en Jamaica. No obstante, la continua escalada de la tasa de infección acusa la necesidad de una educación con respecto al estigma y la discriminación - factores que atizan la diseminación del virus. Se realizaron esfuerzos significativos por recabar el apoyo de las corporaciones en Jamaica a fin de que redoblen sus esfuerzos y provean recursos para abordar la continua escalada de la epidemia del SIDA en Jamaica. El Scotiabank de Jamaica respondió con una iniciativa educacional única. MÉTODOS: La Competencia nacional de debates sobre el VIH y el SIDA patrocinada por Scotiabank en las escuelas primarias 2006-2007, se llevó a cabo por un período de siete meses. Estuvo abierta a instituciones de nivel primario, gubernamentales y privadas en toda la isla. RESULTADOS: Un total de 91 instituciones compitieron entre sí, debatiendo 16 puntos (es decir, asuntos) en 417 debates desde las primeras rondas preliminares hasta las finales. Los puntos a debatir reflejaban preocupaciones curriculares y extra-curriculares, enfatizaban los valores de la compasión, los estilos de vida saludables, el pensamiento crítico y los derechos de los niños. También enviaban mensajes de anti-discriminación, y de responsabilidad de la comunidad y los padres. Si bien la comunicación entre los organizadores y las escuelas, resultó por momentos un verdadero reto, las escuelas se subscribieron a la actividad (los debates) por la concientización que traia consigo y por el potencial para desarrollar a los estudiantes. Se trató también de elevar el nivel de conciencia entre los maestros, los padres y la comunidad en general. CONCLUSIÓN: La retroalimentación al final elogiaba los debates como una estrategia valiosa para la concientización así como para el desarrollo del potencial del estudiante y la unidad en torno a una causa común.

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BACKGROUND AND PURPOSE: The Government of Jamaica, through the Ministry of Health and other ministries, assisted by international funding agencies and members of non-governmental organizations, has diligently led the charge to reduce the incidence ofHIV and AIDS in Jamaica. Yet, the continued escalation in the infection rate attested to the need for education towards the reduction of stigma and discrimination, factors that fuel the spread of the virus. Significant efforts were made to woo corporations in Jamaica to redouble their efforts and provide resources to address the continued escalation of the AIDS epidemic in Jamaica. Scotiabank Jamaica responded with a unique educational initiative. METHODS: The Scotiabank National Primary Schools HIV and AIDS Debating Competition in 2006-2007 was conducted over a seven-month period. It was opened to primary-level, government and private institutions islandwide. RESULTS: A total of91 institutions competed with each other debating 16 moots (i.e., topics) in 417 debates from the first preliminary rounds through to the final. Moots reflected curricular and extracurricular concerns, emphasized the values of compassion, healthy lifestyles, critical thinking and child rights; they also sent messages of anti-discrimination, and parental and community responsibilities. Whereas communication between the organizers and the schools was sometimes challenging, schools subscribed to the activity (debates) for the awareness it brought and for the potential for developing students. Attempts were also made to raise awareness among teachers, parents and the general community. CONCLUSION: Feedback at the end acclaimed the debates as a valuable strategy for building awareness as well as development of student potential and unity around a common cause.

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Out of the 18,942 flavedo expressed sequences (clusters plus singletons) in Citrus sinensis from the Citrus EST Project (CitEST), 25 were statistically supported to be differentially expressed in this tissue after a double in silico hybridization strategy against leaf-, flower-, and bark-derived ESTs. Five of them, two terpene synthases and three O-methyltransferases, are absent in the other citrus tissues with concomitant 2x2 statistics, supporting the hypothesis that they are putative flavedo-specific expressed sequences. The pattern of these differentially expressed sequences during fruit development suggests that most of them are developmentally regulated. Some expressed gene products, including a putative germin-like protein highly expressed in flavedo, are shown to be promising candidates for further characterization. In addition to promoter seeking, this kind of analysis can lead to gene discovery, tissue-specific and tissue-enriched expression pattern predictions (as shown herein) and can also be adopted as an in silico first, and probably reliable approach, for detecting expression profiles from EST sequencing efforts before experimental validation is available or for heuristically guiding that validation.

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Citrus species are known by their high content of phenolic compounds, including a wide range of flavonoids. In plants, these compounds are involved in protection against biotic and abiotic stresses, cell structure, UV protection, attraction of pollinators and seed dispersal. In humans, flavonoid consumption has been related to increasing overall health and fighting some important diseases. The goals of this study were to identify expressed sequence tags (EST) in Citrus sinensis (L.) Osbeck corresponding to genes involved in general phenylpropanoid biosynthesis and the key genes involved in the main flavonoids pathways (flavanones, flavones, flavonols, leucoanthocyanidins, anthocyanins and isoflavonoids). A thorough analysis of all related putative genes from the Citrus EST (CitEST) database revealed several interesting aspects associated to these pathways and brought novel information with promising usefulness for both basic and biotechnological applications.

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Terpenoids constitute the largest and most diverse class of natural products. They are important factors for aroma and flavor, and their synthesis is basically done from two compounds: isopentenyl diphosphate and dimethylallyl diphosphate. Isopentenyl diphosphate is synthesized through two different pathways, one that occurs in the cytoplasm and one in the plastid. With the sequencing of ESTs from citrus, we were able to perform in silico analyses on the pathways that lead to the synthesis of terpenes as well as on the terpene synthases present in sweet orange. Moreover, expression analysis using real-time qPCR was performed to verify the expression pattern of a terpene synthase in plants. The results show that all the pathways for isopentenyl diphosphate are present in citrus and a high expression of terpene synthases seems to have an important role in the constitution of the essential oils of citrus.

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CitEST project resulted in the construction of cDNA libraries from different Citrus sp. tissues under various physiological conditions. Among them, plantlets of Rangpur lime were exposed to hydroponic conditions with and without water stress using PEG6000. RNA from roots was obtained and generated a total of 4,130 valid cDNA reads, with 2,020 from the non-stressed condition and 2,110 from the stressed set. Bioinformatic analyses measured the frequency of each read in the libraries and yielded an in silico transcriptional profile for each condition. A total of 40 contigs were differentially expressed and allowed to detect up-regulated homologue sequences to well known genes involved in stress response, such as aquaporins, dehydrin, sucrose synthase, and proline-related synthase. Some sequences could not be classified by using FunCat and remained with an unknown function. A large number of sequences presented high similarities to annotated genes involved with cell energy, protein synthesis and cellular transport, suggesting that Rangpur lime may sustain active cell growth under stressed condition. The presence of membrane transporters and cell signaling components could be an indication of a coordinated morphological adaptation and biochemical response during drought, helping to explain the higher tolerance of this rootstock to water stress.

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In order to understand the genetic responses resulting from physiological changes that occur in plants displaying citrus variegated chlorosis (CVC) symptoms, we adopted a strategy of comparing two EST libraries from sweet orange [Citrus sinensis (L.) Osbeck]. One of them was prepared with plants showing typical CVC symptoms caused by Xylella fastidiosa and the other with non-inoculated plants. We obtained 15,944 ESTs by sequencing the two cDNA libraries. Using an in silico hybridization strategy, 37 genes were found to have significant variation at the transcriptional level. Within this subset, 21 were up-regulated and 16 were down-regulated in plants with CVC. The main functional categories of the down-regulated transcripts in plants with CVC were associated with metabolism, protein modification, energy and transport facilitation. The majority of the up-regulated transcripts were associated with metabolism and defense response. Some transcripts associated with adaptation to stress conditions were up-regulated in plants with CVC and could explain why plants remain alive even under severe water and nutritional stress. Others of the up-regulated transcripts are related to defense response suggesting that sweet orange plants activate their defense machinery. The genes associated with stress response might be expressed as part of a secondary response related to physiological alterations caused by the infection.

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Citrus is the most important fruit crop in Brazil and Citrus tristeza virus (CTV) is considered one of the most important pathogens of citrus. Most citrus species and varieties are susceptible to CTV infection. However, Poncirus trifoliata, a close relative of citrus, is resistant to the virus. In order to better understand the responses of citrus plants to the infection of CTV, we constructed expressed sequence tag (EST) libraries with tissues collected from Poncirus trifoliata plants, inoculated or not with Citrus tristeza virus at 90 days after inoculation, grafted on Rangpur lime rootstocks. We generated 17,867 sequence tags from Poncirus trifoliata inoculated (8,926 reads) and not (8,941 reads) with a severe CTV isolate. A total of 2,782 TCs (Tentative Consensi sequences) were obtained using both cDNA libraries in a single clusterization procedure. By the in silico hybridization approach, 289 TCs were identified as differentially expressed in the two libraries. A total of 121 TCs were found to be overexpressed in plants infected with CTV and were grouped in 12 primary functional categories. The majority of them were associated with metabolism and defense response. Some others were related to lignin, ethylene biosynthesis and PR proteins. In general, the differentially expressed transcripts seem to be somehow involved in secondary plant response to CTV infection.