[Mediastinal choriocarcinoma. A case report].
Explore the source record for details and available documents.
Antineoplastic Agents↗
Biomedical subjects
G Estrada
Publications and source records attributed to G Estrada.
PNA molecular beacons for rapid detection of PCR amplicons.
The authors have developed a method for rapid detection of polymerase chain reaction (PCR) amplicons based on surface immobilized PNA-DNA hybrid probes ('molecular beacons') that undergo a fluorescent-linked conformational change in the presence of a complementary DNA target. Amplicons can be detected by simply adding a PCR reaction to a microtitre-well containing the previously immobilized probe, and reading the generated fluorescence. No further transfers or washing steps are involved. The authors demonstrate the specificity of the method for the detection of ribosomal DNA from Entamoeba histolytica.
Animals↗
Defective intracellular processing of lactase-phlorizin hydrolase protein in rats prenatally exposed to ethanol.
We have previously shown that fetal exposure to ethanol in rats produces both structural and biochemical abnormalities in absorptive enterocytes. Among the indicators of injury are derangements in the expression of lactase-phlorizin hydrolase (LPH), which is an essential enzyme for the assimilation of milk. In an animal model of fetal alcohol syndrome, unsuckled newborn rats prenatally exposed to maternal ethanol revealed a 10- to 15-fold increase in the number of LPH mRNA molecules per absorptive enterocyte, compared with controls (Estrada et al., Alcohol. Clin. Exp. Res. 20:1662-1668, 1996). However, lactase activity per cell was similar in both groups. The aim of this study was to characterize the effect of prenatal exposure to ethanol on the processing of LPH mRNA and protein. RNase protection assays using 3'- and 5'-directed antisense RNA probes revealed that the LPH mRNA from ethanol-exposed pups is full length. However, metabolic labeling, followed by immunoprecipitation using an anti-LPH monoclonal antibody, demonstrated a significant alteration in LPH protein processing. Intestinal explants from 21-day ethanol-exposed fetuses that were chased 30 min after a [35S]methionine pulse showed greater amounts of newly synthesized LPH precursors (205 and 220 kDa) and low molecular weight degradation products than controls. However, despite the increases in LPH precursor, the amount of 130 kDa mature LPH was similar in ethanol-exposed and control explants. These data suggest an increase in intracellular degradation of LPH precursor in rats prenatally exposed to ethanol, which occurs before its insertion into the microvillus membrane. Biosynthesis of LPH appears to be upregulated at the transcriptional level, which overcomes the degradation of LPH precursor during processing.
Animals↗
Ethanol in utero induces epithelial cell damage and altered kinetics in the developing rat intestine.
The effect of prenatal ethanol exposure on the intestinal maturation of rat fetuses was investigated to understand the nutritional alterations found in the offspring of alcoholic mothers. Female Wistar rats were maintained on solid diet and 25% ethanol solution as drinking fluid during pregnancy, and non-alcoholic isocaloric pregnant mothers were used as controls. At birth, intestines from unsuckled pups were removed for study. The weight and length of the intestine decreased significantly when ethanol was present in utero. Ultrastructural evaluation of the epithelium revealed loss of contact between neighboring enterocytes and abnormal dilation of the cisternae of the Golgi apparatus in ethanol-exposed pups. Further, increased lysosome-like vesiculation and enhanced lysosomal beta-galactosidase activity was observed in these neonates. The total number of absorptive enterocytes in the epithelium was reduced by 30% in ethanol-exposed neonates as compared to controls, due to altered cell growth and death during fetal life. Ethanol in utero stimulated epithelial cell migration which compensated cell loss, as demonstrated by 5'-Bromodeoxyuridine labeling. These findings could have important implications for the assimilation of nutrients and failure to thrive in infants with fetal alcohol syndrome.
Animals↗
Quantitative analysis of lactase-phlorizin hydrolase expression in the absorptive enterocytes of newborn rat small intestine.
At birth, the mammalian small intestine displays regional differences in morphology as well as complex proximal-to-distal (horizontal) patterns of protein distribution. Lactase-phlorizin hydrolase (LPH), an enterocyte-specific disaccharidase crucial for the digestion of lactose in milk, reveals a characteristic horizontal pattern of expression at birth. However, it is not certain whether this topographic pattern is due to variations in epithelial structure along the length of the small intestine or to regional differences in the transcription of the LPH gene. In order to understand the mechanisms that regulate the regionalization of LPH at birth, we characterized the epithelial structure along the horizontal axis using stereologic techniques and correlated these data with the patterns of lactase activity and LPH mRNA abundance in the small intestine of unsuckled, newborn rats. Epithelial volume and microvillar surface area per unit of intestinal length decreased three-to fourfold from duodenum to distal ileum. In contrast, lactase activity and LPH mRNA abundance were highest in proximal jejunum and lowest in the most proximal and distal ends of the small intestine. Mean lactase activity per cell in proximal duodenum, proximal jejunum, and distal ileum was estimated at 12.0, 26.7, and 5.6 nU/absorptive enterocyte, respectively, and paralleled the concentration of LPH mRNA in the same segments: 20, 45, and 15 molecules of LPH mRNA/absorptive enterocyte. Our data indicate that horizontal gradients of lactase activity in the newborn rat intestine do not depend on epithelial organization or on enteral factors, since the horizontal gradient is established before suckling. Each absorptive enterocyte along the small intestine expresses lactase activity in a position-dependent manner which is controlled at the level of mRNA abundance.
Absorption↗
Sequence-specific detection of PCR-amplified DNA by restriction enzyme release of hybrids.
We have developed a method to detect PCR amplicons that contain a restriction enzyme site. The method is called Polymerase Chain Reaction-Hybridization and Enzymatic Release Assay (PCR-HERA). The PCR product is hybridized to a synthetic oligonucleotide that is immobilized on a microtitre plate. Specific cleavage of the resulting hybrid by a restriction endonuclease liberates a fluorescein labeled arm of the immobilized DNA. We demonstrate the use of PCR-HERA to detect species-specific sequences of extra-chromosomal, ribosomal DNA, of Entamoeba histolytica. This highly specific assay does not require any washing steps and can be easily automated.
Animals↗
Prenatal ethanol exposure alters the expression of intestinal hydrolase mRNAs in newborn rats.
To gain insight into the postnatal growth delay induced by ethanol in utero, we characterized functional impairments of the small intestine of neonatal rats prenatally exposed to ethanol using a well-described model of gestational alcoholism (25% ethanol w/v in the drinking water). Expression of the intestinal enzymes-lactase-phlorizin hydrolase (LPH) and intestinal alkaline phosphatase (IAP)-that are critical for enteral nutrition of neonates was studied. Characteristic patterns of LPH and IAP expression along the proximal-distal (horizontal) and crypt-villus (vertical) axes of the small intestine, as well as the intracellular localization of LPH and IAP mRNAs and immunoreactive proteins within absorptive enterocytes, were not altered by prenatal exposure to ethanol. However, a 10- to 15-fold increase in the number of LPH and IAP mRNA molecules per absorptive enterocyte was found throughout the intestine of ethanol-exposed neonates, compared with controls, whereas lactase and alkaline phosphatase activities per enterocyte remained unchanged. These findings suggest that ethanol in utero alters the mRNA abundance of epithelial enzymes in newborn rat small intestine. Changes in mRNA abundance could be an important aspect of enterocyte adaptation to high ethanol concentrations in gastrointestinal amniotic fluid of ethanol-exposed fetuses.
Alkaline Phosphatase↗
Changes in the enterocyte cytoskeleton in newborn rats exposed to ethanol in utero.
BACKGROUND: Cytoskeletal changes after longterm exposure to ethanol have been described in a number of cell types in adult rat and humans. These changes can play a key part in the impairment of nutrient assimilation and postnatal growth retardation after prenatal damage of the intestinal epithelium produced by ethanol intake. AIMS: To determine, in the newborn rat, which cytoskeletal proteins are affected by longterm ethanol exposure in utero and to what extent. ANIMALS: The offspring of two experimental groups of female Wistar rats: ethanol treated group receiving up to 25% (w/v) of ethanol in the drinking fluid and control group receiving water as drinking fluid. METHODS: Single and double electron microscopy immunolocalisation and label density estimation of cytoskeletal proteins on sections of proximal small intestine incubated with monoclonal antibodies against actin, alpha-tubulin, cytokeratin (polypeptides 1, 5, 6, 7, 8, 10, 11, and 18), and with a polyclonal antibody anti-beta 1,4-galactosyl transferase as trans golgi (TG) or trans golgi network (TGN) marker, or both. SDS-PAGE technique was also performed on cytoskeletal enriched fractions from small intestine. Western blotting analysis was carried out by incubation with the same antibodies used for immunolocalisation. RESULTS: Intestinal epithelium of newborn rats from the ethanol treated group showed an overexpression of cytoskeletal polypeptides ranging from 39 to 54 kDa, affecting actin and some cytokeratins, but not tubulin. Furthermore, a cytokeratin related polypeptide of 28-29 kDa was identified together with an increase in free ubiquitin in the same group. It was noteworthy that actin and cytokeratin were abnormally located in the TG or the TGN, or both. CONCLUSIONS: Longterm exposure to ethanol in utero causes severe dysfunction in the cytoskeleton of the developing intestinal epithelium. Actin and cytokeratins, which are involved in cytoskeleton anchoring to plasma membrane and cell adhesion, are particularly affected, showing overexpression, impaired proteolysis, and mislocalisation.
Animals↗
Transcriptional regulation of intestinal hydrolase biosynthesis during postnatal development in rats.
Lactase-phlorizin hydrolase (LPH) and sucrase-isomaltase (SI) are intestine-specific microvillus membrane hydrolases whose specific activities demonstrate reciprocal regulation during development but whose mechanisms of regulation have not been fully defined. To investigate transcriptional control of these two proteins, the rat LPH and SI genes were cloned, and antisense probes for preprocessed mRNAs (pre-mRNAs) were developed from intron sequence. LPH mRNA, as measured by quantitative ribonuclease (RNase) protection assays, was abundant before weaning and decreased two- to fourfold during weaning, whereas SI mRNA was first detected 14 days after birth and increased rapidly to abundant levels by age 28 days. LPH and SI pre-mRNA levels paralleled those of their respective mRNAs. LPH transcriptional rate declined during weaning, whereas that of SI increased during this time as determined by RNase protection assays of pre-mRNAs and nuclear run-on assays. In the adult rat, LPH mRNA was restricted to the jejunum and proximal ileum, whereas SI mRNA was detected throughout the small intestine, a pattern regulated by transcriptional rate as confirmed by nuclear run-on assays. Lactase and sucrase specific activities correlated well with their respective protein and mRNA concentrations in all experiments. We conclude that gene transcription plays a major role in the developmental and horizontal regulation of LPH and SI biosynthesis and that these two genes are regulated differently in rat small intestine.
Aging↗
Chilean hazelnut butter, a new alternative for consumers.
Four formulations of Chilean hazelnut butter were prepared containing Chilean hazelnut paste and 5%, 10%, 15% and 20% margarine. As the level of margarine was increased to 20%, the protein and crude fiber content decreased markedly, while those of moisture, crude fat and calories increased. After 90 days of storage, neither the samples stored at 5 degrees C nor those stored at 15 degrees C showed any objectionable effects both from the bacteriological and chemical point of view. Sensory analyses, including quality and acceptability studies, were performed on the various blends. Flavor, color and taste were improved by the addition of margarine to the butter formulas. It is concluded, therefore, that Chilean hazelnut butter represents a new and interesting alternative for human nourishment.
Chile↗
[Renal carcinoma and solitary pulmonary nodule].
Renal cell carcinoma with solitary metastasis detected at the time of diagnosis has been much discussed and its excision is considered to achieve favorable results. Herein we describe a patient with a solitary pulmonary lesion coexisting with a large renal cell carcinoma. The patient was submitted to radical surgery and the pathological analysis revealed a benign pulmonary tumor with no relationship to the renal cancer.
Aged↗
[Multiple primary pulmonary carcinomas].
Three cases of multiple simultaneous primary lung carcinomas are presented, in which diagnosis was established by post-surgery pathological exam. In all three cases, chest X-ray showed pulmonary masses suggestive or clinical malignancy, and pre-surgery pathological diagnosis or squamous lung carcinoma. During thoracotomy or in the resected segment, a second lesion we confirmed which made resection necessary being this second lesion classified as lung adenocarcinoma.
Adenocarcinoma↗
[Chronic necrotizing pulmonary aspergillosis].
Explore the source record for details and available documents.
Aspergillosis↗
Identification and isolation of human insulin A and B chains by high-performance liquid chromatography.
A method for the isolation, identification and quantification of human insulin A and B chains by high-performance liquid chromatography (HPLC) is described. These chains were isolated from a peptide mixture produced by E. coli with modified genes obtained by genetic engineering. The method is based on the use of hydrophilic reagents, forming ion pairs in a reversed-phase column. Because some undesirable effects resulting from the use of phosphoric acid were observed, especially with the B chain, a new HPLC method was developed for each of the two human insulin chains. The use of trifluoroacetic acid as a counter ion for the A chain and of formic acid for the B chain led to the rapid isolation and purification of each chain by HPLC. The advantage of this method is that it provides a highly pure product, which was identified by polyacrylamide gel electrophoresis and amino acid analysis.
Amino Acids↗
[Intercostal cryolysis. Relief of post-thoracotomy pain].
Explore the source record for details and available documents.
Analgesics, Opioid↗