RESUMO
Since ancient times, breastfeeding has been the fundamental way of nurturing the newborn. The benefits of breast milk are widely known, as it is a source of essential nutrients and provides immunological protection, as well as developmental benefits, among others. However, when breastfeeding is not possible, infant formula is the most appropriate alternative. Its composition meets the nutritional requirements of the infant, and its quality is subject to strict control by the authorities. Nonetheless, the presence of different pollutants has been detected in both matrices. Thus, the aim of the present review is to make a comparison between the findings in both breast milk and infant formula in terms of contaminants in the last decade, in order to choose the most convenient option depending on the environmental conditions. For that, the emerging pollutants including metals, chemical compounds derived from heat treatment, pharmaceutical drugs, mycotoxins, pesticides, packaging materials, and other contaminants were described. While in breast milk the most concerning contaminants found were metals and pesticides, in infant formula pollutants such as metals, mycotoxins, and packaging materials were the most outstanding. In conclusion, the convenience of using a feeding diet based on breast milk or either infant formula depends on the maternal environmental circumstances. However, it is important to take into account the immunological benefits of the breast milk compared to the infant formula, and the possibility of using breast milk in combination with infant formula when the nutritional requirements are not fulfilled only with the intake of breast milk. Therefore, more attention should be paid in terms of analyzing these conditions in each case to be able to make a proper decision, as it will vary depending on the maternal and newborn environment.
Assuntos
Poluentes Ambientais , Praguicidas , Recém-Nascido , Lactente , Feminino , Humanos , Leite Humano/química , Fórmulas Infantis , Poluentes Ambientais/análise , Fenômenos Fisiológicos da Nutrição do Lactente , Aleitamento Materno , Praguicidas/análiseRESUMO
Breast cancer is the second most common cancer in Peruvian women. Due to limitations in national breast cancer screening programs, especially in rural areas, more than 50% of cases of breast cancer in Peru are diagnosed in advanced stages. In collaboration with a local clinic registered as a nongovernmental organization (CerviCusco), RAD-AID International aims to create a sustainable diagnostic structure to improve breast cancer screening in Cuzco. With the support of local, national, and international partners that have collaborated in analyzing radiological resources, raising awareness in the population, acquiring equipment, training clinical staff, and building referral networks, our teams of radiologists, included in the RAD-AID team, have participated in training CerviCusco staff in breast ultrasound, thus enabling additional training for radiology residents through a regulated international collaboration.
Assuntos
Neoplasias da Mama , Radiologia , Neoplasias da Mama/diagnóstico por imagem , Detecção Precoce de Câncer , Feminino , Humanos , Peru , VoluntáriosRESUMO
Breast cancer is the second most common cancer in Peruvian women. Due to limitations in national breast cancer screening programs, especially in rural areas, more than 50% of cases of breast cancer in Peru are diagnosed in advanced stages. In collaboration with a local clinic registered as a nongovernmental organization (CerviCusco), RAD-AID International aims to create a sustainable diagnostic structure to improve breast cancer screening in Cuzco. With the support of local, national, and international partners that have collaborated in analyzing radiological resources, raising awareness in the population, acquiring equipment, training clinical staff, and building referral networks, our teams of radiologists, included in the RAD-AID team, have participated in training CerviCusco staff in breast ultrasound, thus enabling additional training for radiology residents through a regulated international collaboration.
RESUMO
The management of patients with head and neck cancer implies a multidisciplinary treatment with surgery, radiotherapy and chemotherapy. Imaging is crucial in their follow-up, especially when the tumor recurrence is not clinically evident. Radiologically distinguishing post-treatment changes from a tumor recurrence is a challenge due to the anatomical alteration due to surgical techniques and their reconstructions, radiotherapy treatment and chemotherapeutic guidelines. The differential diagnosis must include the possible complications derived from radiotherapy (mucosal necrosis, osteoradionecrosis, vasculopathy, cerebral radionecrosis) and surgery (wound infections, flap necrosis, fistulas,...). A wide knowledge of the expected findings of multimodal treatment and its complications is essential for an accurate diagnosis of tumor recurrence. Finally, choosing the appropriate image study and having a baseline post-treatment study is also relevant for a suitable radiological control.
Assuntos
Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Recidiva Local de Neoplasia/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Lesões por Radiação/diagnóstico por imagem , Radiologistas , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Diagnóstico Diferencial , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Retalhos Cirúrgicos , Tomografia Computadorizada por Raios X , UltrassonografiaRESUMO
The number of computed tomography studies done in emergency departments has increased substantially, and with this increase the controversy about whether positive oral contrast agents are necessary in all patients has also grown. The great image quality provided by multidetector computed tomography scanners, the increase in intraabdominal fat (as a natural element that provides contrast for separating the bowel loops) related with the increased prevalence of obesity in the population, and the potential drawbacks associated with the use of high-density oral contrast agents argue against the generalized us of these agents. This article aims to evaluate the effects of omitting the use of this type of oral contrast material for computed tomography examinations required in the emergency department for suspicion of acute abdominal pathology through an efficient literature search among recent publications.
Assuntos
Abdome Agudo/diagnóstico por imagem , Meios de Contraste/administração & dosagem , Tomografia Computadorizada por Raios X/métodos , Dor Abdominal/diagnóstico por imagem , Doença Aguda , Administração Oral , Apendicite/diagnóstico por imagem , Serviço Hospitalar de Emergência , Humanos , Injeções Intravenosas , Guias de Prática Clínica como Assunto , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Procedimentos DesnecessáriosRESUMO
Two strains of tomato aspermy cucumovirus, 1-TAV and V-TAV, differ in the severity of the symptoms induced in Nicotiana tabacum: 1-TAV induces a severe chlorotic mottle that appears 5 days post inoculation (d.p.i.) in the second systemic leaf, while V-TAV-infected plants show a mild chlorotic mottle, unevenly distributed in the leaf lamina, that appears 7 d.p.i. in the third or fourth systemic leaf. The manipulation of full-length cDNA clones giving infectious transcripts of V-TAV RNAs 1, 2, and 3 and 1-TAV RNA 3 revealed that the slow, mild phenotype of V-TAV maps to the movement protein (MP) gene. By site-directed mutagenesis it was further shown that this phenotype co-segregates with a single nucleotide substitution that introduces an in-frame UAA stop codon at the fourth position of the MP open reading frame of V-TAV. The presence of this stop codon results in a diminished expression of the MP in both tobacco protoplasts and leaves. Analyses of the progress of infection and of the time course of MP and coat protein accumulation show that the low level of MP in V-TAV-infected leaves limits the rate of cell-to-cell movement and leads to the mild phenotype. Data from the infectivity of RNA 3 transcripts with or without this stop codon, plus data from in vitro translation of virion or transcript RNA 3, suggest that the small amount of MP observed in V-TAV-infected leaves is expressed from a minor RNA 3 subpopulation lacking the stop codon.
Assuntos
Cucumovirus/genética , Cucumovirus/patogenicidade , Proteínas Virais/genética , Sequência de Aminoácidos , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular , DNA Viral/genética , Expressão Gênica , Solanum lycopersicum/virologia , Dados de Sequência Molecular , Proteínas do Movimento Viral em Plantas , Plantas Tóxicas , Especificidade da Espécie , Nicotiana/virologia , Virulência/genéticaRESUMO
The objective of the present study was to evaluate the effects of microcystin-LR (MCLR) on the activity of membrane enzymes from intestinal mucosa. In addition, serum chemistry and peroxidative status of both serum and intestinal homogenate were evaluated after treatment with MCLR. Wistar rats were treated with intraperitoneal injection of either 100 microg pure MCLR/Kg body weight or saline solution. A significant increase in liver weight and altered serum enzyme activities were found in MCLR-treated rats, indicating damage to the liver in these rats, as previously suggested. A higher specific activity of sucrase (1.5-fold) was observed after the administration of MCLR, whereas other intestinal apical membrane enzymes, such as lactase, maltase and alkaline phosphatase were not modified by the treatment. The specific activities of acid phosphatase and succinate dehydrogenase, markers for lysosomal and mitochondrial membranes, respectively, were also increased (32% and 60%, respectively) in treated rats. The analysis of lipid peroxidation showed that the peroxidative status was increased in both serum and intestinal mucosa from MCLR-treated rats, reflecting an excess production of oxygen free radicals induced by this cyanobacterial toxin. In conclusion, this study shows that acute exposure to MCLR affects the intestinal physiology by modifying the intestinal peroxidation status as well as the activity of membrane enzymes.
Assuntos
Membrana Celular/enzimologia , Inibidores Enzimáticos/metabolismo , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/enzimologia , Peptídeos Cíclicos/metabolismo , Peptídeos Cíclicos/farmacologia , Animais , Toxinas Bacterianas/metabolismo , Toxinas Bacterianas/farmacologia , Análise Química do Sangue , Membrana Celular/efeitos dos fármacos , Mucosa Intestinal/citologia , Peroxidação de Lipídeos , Masculino , Toxinas Marinhas , Microcistinas , Ratos , Ratos WistarRESUMO
Systemic movement of Cucumber green mottle mosaic virus (CGMMV) in cucumber plants was shown to be from photoassimilate source to sink, thus indicating phloem transport. Nevertheless, CGMMV was not detected by immunocytochemical procedures in the intermediary cell-sieve element complex in inoculated cotyledons, where photoassimilate loading occurs. In stem internodes, CGMMV was first localized in the companion cells of the external phloem and subsequently in all tissues except the medulla, therefore suggesting leakage of the virus from, and reloading into, the transport phloem during systemic movement. In systemically infected sink leaves, CGMMV was simultaneously detected in the xylem and phloem. Interestingly, CGMMV accumulated to high levels in the differentiating tracheids of young leaves implying that the xylem could be involved in the systemic movement of CGMMV. This possibility was tested using plants in which cell death was induced in a portion of the stem by steam treatment. At 24 degrees C, steam treatment effectively prevented the systemic movement of CGMMV, even though viral RNA was detected in washes of the xylem above the steamed internode suggesting that xylem circulation occurred. At 29 degrees C, CGMMV systemically infected steam-treated cucumber plants, indicating that CGMMV can move systemically via the xylem. Xylem transport of CGMMV was, however, less efficient than phloem transport in terms of the time required for systemic infection and the percentage of plants infected.
Assuntos
Cucumis sativus/virologia , Cucumovirus/fisiologia , Cotilédone/virologia , Cucumovirus/isolamento & purificação , Cucumovirus/patogenicidade , Cucumovirus/ultraestrutura , Microscopia Imunoeletrônica , Doenças das Plantas/virologia , Folhas de Planta/virologia , Replicação ViralRESUMO
The nucleotide substitution C-->A at nucleotide 100 of tomato aspermy cucumovirus (TAV) strain V (V-TAV) RNA segment 3 (RNA3) introduces an ocher stop at the fourth codon of the movement protein open reading frame. Experiments with RNA transcripts from full-length clones showed that this mutation abolished cell-to-cell movement and, thus, infectivity in planta. Heterogeneity analyses on stock V-TAV virion RNA showed that an A at position 100 was present in the molecular population of RNA3 at a frequency of 0.76 and that a C at this position was present at a frequency of 0.24. This result indicates that a fraction of RNA3 molecules complements cell-to-cell movement of movement-defective molecules. It was shown that the mutation C-->A conferred enhanced RNA replication of the defective mutant in tobacco protoplasts. The effect of the mutation on replication was dependent on sequence context, since the same mutation did not affect the replication efficiency in the related TAV strain 1 RNA3. Competition experiments in tobacco protoplasts were done to estimate the fitness during a cell invasion cycle of the movement-defective mutant relative to the wild type (wt). From these data, a lower limit to the degree of complementation of movement-defective molecules by movement-competent ones could be estimated as 0.13. This estimate shows that complementation may play an important role in the determination of genetic structure in RNA genome populations. A further effect of the enhanced replication of the movement-defective mutant was the efficient competition with the wt for the initiation of infection foci in planta.
Assuntos
Cucumovirus/genética , Mutação Puntual , RNA Viral , Proteínas Virais/genética , Alanina , Cucumovirus/metabolismo , Cucumovirus/fisiologia , Cisteína , Teste de Complementação Genética , Heterogeneidade Genética , Solanum lycopersicum/virologia , Proteínas do Movimento Viral em Plantas , Replicação ViralRESUMO
The genetic structure of the population of Watermelon mosaic virus (WMV) in Spain was analysed by the biological and molecular characterisation of isolates sampled from its main host plant, melon. The population was a highly homogeneous one, built of a single pathotype, and comprising isolates closely related genetically. There was indication of temporal replacement of genotypes, but not of spatial structure of the population. Analyses of nucleotide sequences in three genomic regions, that is, in the cistrons for the P1, cylindrical inclusion (CI) and capsid (CP) proteins, showed lower similar values of nucleotide diversity for the P1 than for the CI or CP cistrons. The CI protein and the CP were under tighter evolutionary constraints than the P1 protein. Also, for the CI and CP cistrons, but not for the P1 cistron, two groups of sequences, defining two genetic strains, were apparent. Thus, different genomic regions of WMV show different evolutionary dynamics. Interestingly, for the CI and CP cistrons, sequences were clustered into two regions of the sequence space, defining the two strains above, and no intermediary sequences were identified. Recombinant isolates were found, accounting for at least 7% of the population. These recombinants presented two interesting features: (i) crossover points were detected between the analysed regions in the CI and CP cistrons, but not between those in the P1 and CI cistrons, (ii) crossover points were not observed within the analysed coding regions for the P1, CI or CP proteins. This indicates strong selection against isolates with recombinant proteins, even when originated from closely related strains. Hence, data indicate that genotypes of WMV, generated by mutation or recombination, outside of acceptable, discrete, regions in the evolutionary space, are eliminated from the virus population by negative selection.