Human papillomavirus genotypes in invasive cervical squamous cell carcinoma in Trinidad.

OBJECTIVE: To determine the relative contribution of known high-risk human papillomavirus (HPV) genotypes to the occurrence of cervical cancers in Trinidad. METHODS: The distribution of HPV genotypes in cases of invasive cervical squamous cell carcinoma in Trinidad was investigated. This study was a follow-up to an investigation of HPV genotypes in 310 nonsymptomatic women in Trinidad. The latter study showed that cervical HPV prevalence and heterogeneity of genotypes were high in the study population; notably, the genotypes targeted by the available HPV prophylactic vaccines were not the most common types. RESULTS: The current study of 85 cases of invasive cervical squamous cell carcinomas demonstrated that the previously observed heterogeneity in HPV genotype distribution is lost in cases of invasive cervical cancer, with the vaccine-targeted HPV types HPV 16 and HPV 18 becoming the most prevalent. CONCLUSIONS: HPV 16 and HPV 18 were the primary HPV genotypes associated with cases of invasive squamous cell carcinoma in the current Trinidad study. This strong association leads us to conclude that the HPV vaccines targeting HPV 16 and HPV 18 may contribute to reducing the cervical cancer burden in Trinidad.

Human papillomavirus genotypes and their prevalence in a cohort of women in Trinidad.

OBJECTIVE: Human papillomavirus (HPV) genotypes and their relative prevalences were determined in a cohort of 310 sexually active women in Trinidad, West Indies. METHODS: Cervical samples were collected with Ayre's spatulas and endocervical brushes. Samples were used for the conventional Papanicolaou test and for determining HPV genotypes by amplification of a section of the viral L1 gene, followed by DNA sequencing and probe hybridization. RESULTS: HPV infections were identified in 126 of 310 (40.6%) women. Of them, 83 (65.8%) were infected with high-risk HPV, 16 (12.7%) with low-risk HPV, and 27 (21.4%) with HPV types of unknown risk. HPV 52 (12.7%) was the most frequently occurring high-risk type, followed by HPV 66 (10.3%), HPV 16 (9.5%), and HPV 18 (8.6%). High-risk types HPV 16 and HPV 66 were each found in 3 (20.0%) and HPV 18 was found in 1 (6.6%) of the 15 women with abnormal cytology. CONCLUSIONS: Cervical HPV prevalence and heterogeneity of HPV genotypes are high in this Trinidad cohort. The relative importance of HPV genotypes in the development of cervical lesions needs further investigation in Trinidad in order to better understand the epidemiology of HPV infections as well as to determine the role of HPV testing in the screening, prevention, and control of cervical cancer. This pilot study provided important information on the prevalence of HPV genotypes, which will be used in future nationwide studies.

Characterization of a gene from chromosome 1B encoding the large subunit of ADPglucose pyrophosphorylase from wheat: evolutionary divergence and differential expression of Agp2 genes between leaves and developing endosperm.

A full-length genomic clone containing the gene encoding the large subunit of the ADPglucose pyrophosphorylase (Agp2), was isolated from a genomic library prepared from etiolated shoots of hexaploid wheat (Triticum aestivum L., cv, Chinese Spring). The coding region of this gene is identical to one of the cDNA clones previously isolated from a developing wheat grain cDNA library and is therefore an actively transcribed gene. The sequence represented by the cDNA spans 4.8 kb of the genomic clone and contains 15 introns. 2852 bp of DNA flanking the transcription start site of the gene was cloned upstream of the GUS (beta-glucuronidase) reporter gene. This Agp2::GUS construct and promoter deletions were used to study the pattern of reporter gene expression in both transgenic tobacco and wheat plants. Histochemical analysis of GUS expression in transgenic tobacco demonstrated that the reporter gene was expressed in guard cells of leaves and throughout the seed. In transgenic wheat, reporter gene expression was confined to the endosperm and aleurone with no expression in leaves. The cloned Agp2 gene was located to chromosome 1B by gene-specific PCR with nullisomic-tetrasomic lines. Northern analysis demonstrated that the Agp2 genes are differentially expressed in leaves and developing endosperm; while all three classes of Agp2 genes are transcribed in developing wheat grain endosperm, only one is transcribed in leaves. The differences between the Agp2 genes are discussed in relation to the evolution of hexaploid wheat.

ADP-glucose pyrophosphorylase-deficient pea embryos reveal specific transcriptional and metabolic changes of carbon-nitrogen metabolism and stress responses.

We present a comprehensive analysis of ADP-glucose pyrophosphorylase (AGP)-repressed pea (Pisum sativum) seeds using transcript and metabolite profiling to monitor the effects that reduced carbon flow into starch has on carbon-nitrogen metabolism and related pathways. Changed patterns of transcripts and metabolites suggest that AGP repression causes sugar accumulation and stimulates carbohydrate oxidation via glycolysis, tricarboxylic acid cycle, and mitochondrial respiration. Enhanced provision of precursors such as acetyl-coenzyme A and organic acids apparently support other pathways and activate amino acid and storage protein biosynthesis as well as pathways fed by cytosolic acetyl-coenzyme A, such as cysteine biosynthesis and fatty acid elongation/metabolism. As a consequence, the resulting higher nitrogen (N) demand depletes transient N storage pools, specifically asparagine and arginine, and leads to N limitation. Moreover, increased sugar accumulation appears to stimulate cytokinin-mediated cell proliferation pathways. In addition, the deregulation of starch biosynthesis resulted in indirect changes, such as increased mitochondrial metabolism and osmotic stress. The combined effect of these changes is an enhanced generation of reactive oxygen species coupled with an up-regulation of energy-dissipating, reactive oxygen species protection, and defense genes. Transcriptional activation of mitogen-activated protein kinase pathways and oxylipin synthesis indicates an additional activation of stress signaling pathways. AGP-repressed embryos contain higher levels of jasmonate derivatives; however, this increase is preferentially in nonactive forms. The results suggest that, although metabolic/osmotic alterations in iAGP pea seeds result in multiple stress responses, pea seeds have effective mechanisms to circumvent stress signaling under conditions in which excessive stress responses and/or cellular damage could prematurely initiate senescence or apoptosis.

Human papillomavirus genotypes in invasive cervical squamous cell carcinoma in Trinidad / Genotipos de virus de los papilomas humanos en carcinoma cervicouterino escamocelular invasor en Trinidad

OBJECTIVE: To determine the relative contribution of known high-risk human papillomavirus (HPV) genotypes to the occurrence of cervical cancers in Trinidad. METHODS: The distribution of HPV genotypes in cases of invasive cervical squamous cell carcinoma in Trinidad was investigated. This study was a follow-up to an investigation of HPV genotypes in 310 nonsymptomatic women in Trinidad. The latter study showed that cervical HPV prevalence and heterogeneity of genotypes were high in the study population; notably, the genotypes targeted by the available HPV prophylactic vaccines were not the most common types. RESULTS: The current study of 85 cases of invasive cervical squamous cell carcinomas demonstrated that the previously observed heterogeneity in HPV genotype distribution is lost in cases of invasive cervical cancer, with the vaccine-targeted HPV types HPV 16 and HPV 18 becoming the most prevalent. CONCLUSIONS: HPV 16 and HPV 18 were the primary HPV genotypes associated with cases of invasive squamous cell carcinoma in the current Trinidad study. This strong association leads us to conclude that the HPV vaccines targeting HPV 16 and HPV 18 may contribute to reducing the cervical cancer burden in Trinidad.

OBJETIVO: Determinar la contribución relativa de los diferentes genotipos de virus de los papilomas humanos (VPH) conocidos como de alto riesgo para la aparición de cáncer cervicouterino en Trinidad. MÉTODOS: Se investigó la distribución de los genotipos de VPH en casos de carcinoma cervicouterino escamocelular invasor en Trinidad. Este estudio fue la continuación de una investigación de los genotipos de VPH presentes en 310 mujeres asintomáticas en Trinidad. Este último estudio reveló altas prevalencia de VPH en el cuello uterino y heterogeneidad de los genotipos en la población del estudio; cabe destacar que los genotipos a los que se dirigen las vacunas preventivas de la infección por VPH disponibles no fueron los tipos más frecuentes. RESULTADOS: El presente estudio, llevado a cabo en 85 casos de carcinoma cervicouterino escamocelular invasor, demostró que la heterogeneidad anteriormente observada en la distribución de genotipos de VPH no se mantiene en los casos de cáncer cervicouterino invasor, y que los tipos de VPH objeto de la vacuna, el VPH 16 y el VPH 18, pasan a ser los más prevalentes. CONCLUSIONES: En el presente estudio llevado a cabo en Trinidad, el VPH 16 y el VPH 18 fueron los principales genotipos de VPH asociados con los casos de carcinoma escamocelular invasor. Esta estrecha asociación nos lleva a la conclusión de que las vacunas contra el VPH dirigidas contra el VPH 16 y el VPH 18 pueden contribuir a la reducción de la carga de cáncer cervicouterino en Trinidad.

Human papillomavirus genotypes and their prevalence in a cohort of women in Trinidad / Genotipos del papilomavirus humano y su prevalencia en una cohorte de mujeres en Trinidad

OBJECTIVE: Human papillomavirus (HPV) genotypes and their relative prevalences were determined in a cohort of 310 sexually active women in Trinidad, West Indies. METHODS: Cervical samples were collected with Ayre's spatulas and endocervical brushes. Samples were used for the conventional Papanicolaou test and for determining HPV genotypes by amplification of a section of the viral L1 gene, followed by DNA sequencing and probe hybridization. RESULTS: HPV infections were identified in 126 of 310 (40.6 percent) women. Of them, 83 (65.8 percent) were infected with high-risk HPV, 16 (12.7 percent) with low-risk HPV, and 27 (21.4 percent) with HPV types of unknown risk. HPV 52 (12.7 percent) was the most frequently occurring high-risk type, followed by HPV 66 (10.3 percent), HPV 16 (9.5 percent), and HPV 18 (8.6 percent). High-risk types HPV 16 and HPV 66 were each found in 3 (20.0 percent) and HPV 18 was found in 1 (6.6 percent) of the 15 women with abnormal cytology. CONCLUSIONS: Cervical HPV prevalence and heterogeneity of HPV genotypes are high in this Trinidad cohort. The relative importance of HPV genotypes in the development of cervical lesions needs further investigation in Trinidad in order to better understand the epidemiology of HPV infections as well as to determine the role of HPV testing in the screening, prevention, and control of cervical cancer. This pilot study provided important information on the prevalence of HPV genotypes, which will be used in future nationwide studies.

OBJETIVO: Se determinaron los genotipos del papilomavirus humano (PVH) y su prevalencia relativa en una cohorte de 310 mujeres sexualmente activas de Trinidad, en la zona de las Indias Occidentales. MÉTODOS: Se tomaron muestras del cuello uterino con espátula de Ayre y cepillo endocervical. Las muestras se usaron para llevar a cabo la prueba convencional de Papanicolaou y para determinar los genotipos de PVH mediante la amplificación de una sección del gen vírico L1, seguida de secuenciación del ADN e hibridación con sonda. RESULTADOS: Se encontró una infección por PVH en 126 de las 310 mujeres (40,6 por ciento). De ellas, 83 (65,8 por ciento) estaban infectadas con PVH de alto riesgo, 16 (12,7 por ciento) con PVH de bajo riesgo, y 27 (21,4 por ciento) con tipos de PVH de riesgo desconocido. De los PVH de alto riesgo, el más frecuente fue el PVH 52 (12,7 por ciento), seguido por el PVH 66 (10,3 por ciento), el PVH 16 (9,5 por ciento) y el PVH 18 (8,6 por ciento). Entre las 15 mujeres con citología anormal se encontraron los PVH de alto riesgo 16 y 66 en 3 (20,0 por ciento) mujeres cada uno, y el PVH 18 en 1 (6,6 por ciento). CONCLUSIONES: Tanto la prevalencia de PVH en el cuello uterino como la heterogeneidad de los genotipos de PVH son elevadas en esta cohorte de Trinidad. La importancia relativa de los genotipos de PVH en la aparición de las lesiones cervicales requiere de mayor investigación en Trinidad para conocer más a fondo las características epidemiológicas de las infecciones por PVH, así como para determinar el papel del estudio de los PVH en la detección sistemática, la prevención y el control del cáncer del cuello uterino. Este estudio piloto suministró información importante sobre la prevalencia de los genotipos de PVH, que se usará en futuros estudios que se lleven a cabo en todo el país.

Ectopic expression of an amino acid transporter (VfAAP1) in seeds of Vicia narbonensis and pea increases storage proteins.

Storage protein synthesis is dependent on available nitrogen in the seed, which may be controlled by amino acid import via specific transporters. To analyze their rate-limiting role for seed protein synthesis, a Vicia faba amino acid permease, VfAAP1, has been ectopically expressed in pea (Pisum sativum) and Vicia narbonensis seeds under the control of the legumin B4 promoter. In mature seeds, starch is unchanged but total nitrogen is 10% to 25% higher, which affects mainly globulin, vicilin, and legumin, rather than albumin synthesis. Transgenic seeds in vitro take up more [14C]-glutamine, indicating increased sink strength for amino acids. In addition, more [14C] is partitioned into proteins. Levels of total free amino acids in growing seeds are unchanged but with a shift toward higher relative abundance of asparagine, aspartate, glutamine, and glutamate. Hexoses are decreased, whereas metabolites of glycolysis and the tricarboxylic acid cycle are unchanged or slightly lower. Phosphoenolpyruvate carboxylase activity and the phosphoenolpyruvate carboxylase-to-pyruvate kinase ratios are higher in seeds of one and three lines, indicating increased anaplerotic fluxes. Increases of individual seed size by 20% to 30% and of vegetative biomass indicate growth responses probably due to improved nitrogen status. However, seed yield per plant was not altered. Root application of [15N] ammonia results in significantly higher label in transgenic seeds, as well as in stems and pods, and indicates stimulation of nitrogen root uptake. In summary, VfAAP1 expression increases seed sink strength for nitrogen, improves plant nitrogen status, and leads to higher seed protein. We conclude that seed protein synthesis is nitrogen limited and that seed uptake activity for nitrogen is rate limiting for storage protein synthesis.

Seed-specific promoters direct gene expression in non-seed tissue.

The organ specificity of four promoters that are known to direct seed-specific gene expression was tested. Whereas the phaseolin (phas)- and legumin B4 (leB4)-promoters were from genes encoding 7S and 11S globulins from Phaseolus vulgaris and Vicia faba, respectively, the usp- and the sbp-promoters were from non-storage protein genes of V. faba. The expression of different promoter-reporter gene fusions was followed either by RT-PCR or by registering the reporter enzyme activity in organs of transgenic tobacco, pea, narbon bean, or linseed. In addition to seeds, the promoters directed reporter gene expression in pollen and in seed coats. USP-, vicilin- and legumin-mRNA were detected by RT-PCR in pollen of Pisum sativum and V. faba. Expression during microsporogenesis and embryogenesis seems to be a general character of various seed protein genes.