RESUMO
Congenital diaphragmatic hernia (CDH) is associated with thoracic compression of the lungs and heart caused by the herniated abdominal content, leading to cardiac modifications including pressure and vascular changes. Our aim was to investigate the experimental immunoexpression of the capillary proliferation, activation, and density of Ki-67, VEGFR2, and lectin in the myocardium after surgical creation of a diaphragmatic defect. Pregnant New Zealand rabbits were operated on the 25th gestational day in order to create left-sided CDH (LCDH, n=9), right-sided CDH (RCDH, n=9), and Control (n=9), for a total of 27 fetuses in 19 pregnant rabbits. Five days after the procedure, animals were sacrificed, and histology and immunohistochemistry studies of the harvested hearts were performed. Total body weight and heart weight were not significantly different among groups (P=0.702 and 0.165, respectively). VEGFR2 expression was increased in both ventricles in the RCDH group (P<0.0001), and Ki-67 immunoexpression was increased in the left ventricle in the LCDH group compared to Control and RCDH groups (P<0.0001). In contrast, capillary density was reduced in the left ventricle in the LCDH compared to the Control and RCDH groups (P=0.002). Left and right ventricles responded differently to CDH in this model depending on the laterality of the diaphragmatic defect. This surgical model of diaphragmatic hernia was associated with different expression patterns of capillary proliferation, activation, and density in the myocardium of the ventricles of newborn rabbits.
Assuntos
Hérnias Diafragmáticas Congênitas , Gravidez , Feminino , Coelhos , Animais , Hérnias Diafragmáticas Congênitas/complicações , Hérnias Diafragmáticas Congênitas/patologia , Antígeno Ki-67 , Pulmão/patologia , Miocárdio , FetoRESUMO
Congenital diaphragmatic hernia (CDH) is associated with thoracic compression of the lungs and heart caused by the herniated abdominal content, leading to cardiac modifications including pressure and vascular changes. Our aim was to investigate the experimental immunoexpression of the capillary proliferation, activation, and density of Ki-67, VEGFR2, and lectin in the myocardium after surgical creation of a diaphragmatic defect. Pregnant New Zealand rabbits were operated on the 25th gestational day in order to create left-sided CDH (LCDH, n=9), right-sided CDH (RCDH, n=9), and Control (n=9), for a total of 27 fetuses in 19 pregnant rabbits. Five days after the procedure, animals were sacrificed, and histology and immunohistochemistry studies of the harvested hearts were performed. Total body weight and heart weight were not significantly different among groups (P=0.702 and 0.165, respectively). VEGFR2 expression was increased in both ventricles in the RCDH group (P<0.0001), and Ki-67 immunoexpression was increased in the left ventricle in the LCDH group compared to Control and RCDH groups (P<0.0001). In contrast, capillary density was reduced in the left ventricle in the LCDH compared to the Control and RCDH groups (P=0.002). Left and right ventricles responded differently to CDH in this model depending on the laterality of the diaphragmatic defect. This surgical model of diaphragmatic hernia was associated with different expression patterns of capillary proliferation, activation, and density in the myocardium of the ventricles of newborn rabbits.
RESUMO
A series of studies have shown that the heavy burdens of diarrheal diseases in the first 2 formative years of life in children living in urban shanty towns have negative effects on physical and cognitive development lasting into later childhood. We have shown that APOE4 is relatively common in shanty town children living in Brazil (13.4%) and suggest that APOE4 has a protective role in cognitive development as well as weight-for-height in children with heavy burdens of diarrhea in early childhood (64/123; 52%), despite being a marker for cognitive decline with Alzheimer's and cardiovascular diseases later in life. APOE2 frequency was higher among children with heaviest diarrhea burdens during the first 2 years of life, as detected by PCR using the restriction fragment length polymorphism method, raising the possibility that ApoE-cholesterol balance might be critical for growth and cognitive development under the stress of heavy diarrhea burdens and when an enriched fat diet is insufficient. These findings provide a potential explanation for the survival advantage in evolution of genes, which might raise cholesterol levels during heavy stress of diarrhea burdens and malnutrition early in life.
Assuntos
Apolipoproteínas E/genética , Diarreia Infantil/genética , Polimorfismo Genético/genética , Apolipoproteínas E/metabolismo , Brasil , Desenvolvimento Infantil , Pré-Escolar , Cognição , Estudos de Coortes , Diarreia Infantil/complicações , Diarreia Infantil/metabolismo , Feminino , Frequência do Gene , Genótipo , Humanos , Lactente , Recém-Nascido , Masculino , Mucosa Bucal/citologia , Reação em Cadeia da Polimerase , Fatores SocioeconômicosRESUMO
A series of studies have shown that the heavy burdens of diarrheal diseases in the first 2 formative years of life in children living in urban shanty towns have negative effects on physical and cognitive development lasting into later childhood. We have shown that APOE4 is relatively common in shanty town children living in Brazil (13.4 percent) and suggest that APOE4 has a protective role in cognitive development as well as weight-for-height in children with heavy burdens of diarrhea in early childhood (64/123; 52 percent), despite being a marker for cognitive decline with Alzheimers and cardiovascular diseases later in life. APOE2 frequency was higher among children with heaviest diarrhea burdens during the first 2 years of life, as detected by PCR using the restriction fragment length polymorphism method, raising the possibility that ApoE-cholesterol balance might be critical for growth and cognitive development under the stress of heavy diarrhea burdens and when an enriched fat diet is insufficient. These findings provide a potential explanation for the survival advantage in evolution of genes, which might raise cholesterol levels during heavy stress of diarrhea burdens and malnutrition early in life.
Assuntos
Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Apolipoproteínas E/genética , Diarreia Infantil/genética , Polimorfismo Genético/genética , Apolipoproteínas E/metabolismo , Brasil , Desenvolvimento Infantil , Cognição , Estudos de Coortes , Diarreia Infantil/complicações , Diarreia Infantil/metabolismo , Frequência do Gene , Genótipo , Mucosa Bucal/citologia , Reação em Cadeia da Polimerase , Fatores SocioeconômicosRESUMO
We report on peculiar dynamic features of laser oscillation in a cavity with a semiconductor junction as the gain medium and an intracavity atomic absorber. The output face of the semiconductor is antireflection coated, and lasing action is achieved by using a diffraction grating to close the laser cavity. The spectral analysis of the laser emission evidences a stable emission with narrow linewidth when the oscillating frequency is resonant with the atomic absorber. We also observe frequency bistability and instability. The change between these regimes is controlled through the bias current in a very reproducible way.
RESUMO
The emission frequency of a diode laser submitted to a frequency-dependent optoelectronic feedback is observed to have more than one stable operation point together with a stable power emission. This is, to our knowledge, the first observation of bistability exclusively in the frequency of an optical system. The experiment was carried out with a semiconductor laser coupled to the cesium D2 line by an orthogonally polarized frequency-sensitive optical feedback.
RESUMO
BACKGROUND: Biliary stents constitute an alternative for the palliative treatment of benign or malignant biliary obstruction, biliary strictures, choledocholithiasis, biliary fistulas from lateral lesions of the biliary duct or cystic duct leaks due to slippage of clip closure. Obstruction resulting in cholangitis is common. Proximal migration to the biliary duct or distal migration to the duodenum with subsequent passage per rectum are relatively frequent, but impaction and perforation of the bowel are rare. CASE OUTLINES: Two cases are reported. In one patient a migrated stent impacted in the caecal wall, and in the other the impaction produced a perforation of an adherent small bowel loop. Both patients were treated surgically and made an uneventful recovery. DISCUSSION: Biliary stents migrate in 8-10% of patients and are generally eliminated by natural means. Occasionally they impact and perforate the digestive tract, usually in the duodenum or other fixed areas or in bowel affected by adhesions due to a previous operation. Although endoscopy is the treatment of choice to retrieve them, operation should be performed whenever there is suspicion of perforation of the intestinal wall.
RESUMO
We discuss the properties of selective reflection spectroscopy at the interface between a resonant vapor and a complex dense medium, such as a metallic film layered on a dielectric substrate. We show that in the approximation of a low-density vapor, the signal mixes up the absorptive and dispersive components of the "effective resonant susceptibility" of the vapor, with the mixture amount governed by simple laws of linear optics. Preliminary experiments performed at the interface between Cs vapor (D2, 852-nm line) and a silver-coated glass window are reported, that show qualitatively the effect of the atom-surface van der Waals interaction.