The Estrogen Receptor-α Is Required and Sufficient to Maintain Physiological Glucose Uptake in the Mouse Heart

Estrogens attenuate cardiac hypertrophy and increase cardiac contractility via their cognate estrogen receptors (ERs) ERα and ERβ. Because female sex hormones enhance global glucose use and because myocardial function and mass are tightly linked to cardiac glucose metabolism, we tested the hypothesis that expression and activation of the ERα might be required and sufficient to maintain physiological cardiac glucose uptake in the murine heart. Cardiac glucose uptake quantified in vivo by (18)F-fluorodeoxyglucose positron emission tomography was strongly impaired in ovariectomized compared with gonadal intact female C57BL/6JO mice. The selective ERα agonist 16α-LE2 and the nonselective ERα and ERβ agonist 17β-estradiol completely restored cardiac glucose uptake in ovariectomized mice. Cardiac (18)F-fluorodeoxyglucose uptake was strongly decreased in female ERα knockout mice compared with wild-type littermates. Analysis of cardiac mRNA accumulation by quantitative RT-PCR revealed an upregulation of genes involved in glycolisis and tricarboxylic acid cycle by ERα treatment. In conclusion, systemic activation of ERα is sufficient, and its expression is required to maintain physiological glucose uptake in the murine heart, which is likely to contribute to known cardioprotective estrogen effects.     

Cyclooxygenase-2 Promotes Hepatocellular Apoptosis by Interacting with TNF-α and IL-6 in the Pathogenesis of Nonalcoholic Steatohepatitis in Rats

Background and Purpose

The underlying mechanisms of nonalcoholic steatohepatitis (NASH) are poorly understood, and little is known about hepatocellular apoptosis in NASH. Cyclooxygenase (COX)-2, the key enzyme in eicosanoid metabolism, is highly expressed in NASH. COX-2 can also regulate the release of mediators of inflammation, such as tumor necrosis factor (TNF)-α and interleukin (IL)-6. The aim of our study was to evaluate the effects of COX-2 on hepatocellular apoptosis and the mechanism of the action in the pathogenesis of NASH in rats.

Methods

Sprague-Dawley rats were fed a high-fat diet (HFD) or standard diet for 8 and 12 weeks. COX-2 and cytokines expression in hepatic tissue and TNF-α and IL-6 levels in serum were measured at 8 and 12 weeks. Moreover, celecoxib (10 mg/kg body weight once a day) was administered to rats for 4 weeks to inhibit the expression of COX-2. Liver pathology was assessed by hematoxylin and eosin (H&E) stain and electron microscopy. Hepatocyte apoptosis was evaluated by TUNEL staining.

Results

COX-2 messenger RNA and protein were highly expressed in livers of HFD rats and were correlated with the severity of steatohepatitis (R = 0.82, p < 0.01). COX-2 upregulation was preceded by increases in TNF-α and IL-6. The level of hepatocellular apoptosis was significantly higher in HFD rats than in the control rats. The hepatocellular apoptosis was suppressed by the inhibition of COX-2.

Conclusions

COX-2 may promote hepatocellular apoptosis by interacting with TNF-α and IL-6 in NASH in rats.     

Implications of TNF-α in the pathogenesis and management of GVHD

Clinical graft-versus-host disease (GVHD) symptoms are the result of a complex set of interactions between cellular and soluble factors. One of the key soluble factors is the proinflammatory cytokine, TNF-α, which participates in the initiating events that culminate in GVHD as well as amplifies the disease process once established. The importance of TNF-α in this process has been supported by a series of clinical experiments demonstrating strong correlation between TNF receptor-1 levels and GVHD. TNF-α has both indirect effects, through activating and proliferation pathways of T cells, the main cellular effector of GVHD, and direct effects leading to apoptosis, on GVHD target tissues. Accordingly, TNF-α has been used as a therapeutic target in experimental GVHD prevention and treatment strategies with promising clinical results. TNF-α can be pharmacologically inhibited using soluble TNF receptors or monoclonal antibodies. The optimal dosing and duration of TNF inhibition to prevent or treat GVHD remains under investigation.     

Distribution and Estrogen Regulation of Membrane Progesterone Receptor-β in the Female Rat Brain

Although several studies have reported the localization of membrane progesterone (P(4)) receptors (mPR) in various tissues, few have attempted to describe the distribution and regulation of these receptors in the brain. In the present study, we investigated expression of two mPR subtypes, mPRα and mPRβ, within regions of the brain, known to express estradiol (E(2))-dependent [preoptic area (POA) and hypothalamus] and independent (cortex) classical progestin receptors. Saturation binding and Scatchard analyses on plasma membranes prepared from rat cortex, hypothalamus, and POA demonstrated high-affinity, specific P(4)-binding sites characteristic of mPR. Using quantitative RT-PCR, we found that mPRβ mRNA was expressed at higher levels than mPRα, indicating that mPRβ may be the primary mPR subtype in the rat brain. We also mapped the distribution of mPRβ protein using immunohistochemistry. The mPRβ-immunoreactive neurons were highly expressed in select nuclei of the hypothalamus (paraventricular nucleus, ventromedial hypothalamus, and arcuate nucleus), forebrain (medial septum and horizontal diagonal band), and midbrain (oculomotor and red nuclei) and throughout many areas of the cortex and thalamus. Treatment of ovariectomized female rats with E(2) benzoate increased mPRβ immunoreactivity within the medial septum but not the medial POA, horizontal diagonal band, or oculomotor nucleus. Together, these findings demonstrate a wide distribution of mPRβ in the rodent brain that may contribute to functions affecting behavioral, endocrine, motor, and sensory systems. Furthermore, E(2) regulation of mPRβ indicates a mechanism through which estrogens can regulate P(4) function within discrete brain regions to potentially impact behavior.     

Color Doppler Transesophageal Echocardiography in Detection of Massive Pulmonary Embolism: Is Pulmonary Angiography Always the Gold Standard?

In this article, the potential value of color Doppler in improving diagnostic accuracy of transesophageal echocardiography (TEE) in patients with incomplete obstruction of large pulmonary vessels is illustrated. We present an unusual case of massive pulmonary embolism that was unequivocally detected by color Doppler TEE both before and after pulmonary angiography, which failed to demonstrate filling defects in the pulmonary artery. (ECHOCARDIOGRAPHY, Volume 13, November 1996)     

Ultrastructural Study of Development of Hepatic Necrosis Induced by TNF-α and D-Galactosamine

Recent studies have suggested an associationbetween tumor necrosis factor- (TNF-) andthe development and progression of acute liver failure.To investigate the role of TNF- in the mechanism of massive hepatic necrosis, we studied a mousemodel of TNF- and D-galactosamine (GalN)-inducedhepatic necrosis by ultrastructural analysis.Administration of GalN caused edema of hepatocellular microvilli and widening of sinusoidalendothelial fenestrae (SEF); administration ofTNF- caused only a widening of the SEF. Massivehepatic necrosis with hemorrhage was seen 6 hr afterconcomitant administration of TNF- and GalN. In theultrastructural analysis, edema of the hepatocellularmicrovilli, widening of the SEF, and transmigration ofred blood cells (RBC) and platelets to the space of Disse without exfoliation and necrosis ofthe sinusoidal endothelial cells were observed. Fibrindeposits were seen in areas adjacent to injuredhepatocytes. The diameter of the SEF was significantly greater than in the nontreated group and thegroups treated with TNF- or GalN alone. Theseresults suggest that as a consequence of the increase indiameter of the SEF, transmigration of RBCs andplatelets to the space of Disse may have resulted inmassive hepatic necrosis due to occlusion of themicrocirculation.     

Sulfated Caffeic Acid Dehydropolymer Attenuates Elastase and Cigarette Smoke Extract–induced Emphysema in Rats: Sustained Activity and a Need of Pulmonary Delivery

Background

Although emphysema destroys alveolar structures progressively and causes death eventually, no drug has been discovered to prevent, intervene, and/or resolve this life-threatening disease. We recently reported that sulfated caffeic acid dehydropolymer CDSO3 is a novel potent triple-action inhibitor of elastolysis, oxidation, and inflammation in vitro, and therefore, a potential anti-emphysema agent. However, the in vivo therapeutic potency, duration and mode of actions, and effective route remain to be demonstrated.

Methods

Emphysema was induced in rats with human sputum elastase (HSE) combined with cigarette smoke extract (CSE). CDSO3 at 5, 30, or 100 μg/kg was dosed to the lung or injected subcutaneously at 2, 6, or 24 h before or 1 or 24 h or 1 week after the HSE/CSE instillation. At 1 h or 48 h or on day 21–22 or day 28, lungs were examined for airway-to-blood injurious barrier damage; their elastolytic, oxidative, and inflammatory activities; lung luminal leukocytes infiltration; functional treadmill exercise endurance; and/or morphological airspace enlargement.

Results

CDSO3, when dosed to the lung at 30 or 100 μg/kg, but not via systemic subcutaneous injection, significantly (43–93 %) attenuated HSE/CSE-induced (1) barrier damage measured by luminal hemorrhage and protein leak; (2) elastolytic, oxidative, and inflammatory activities measured with elastase, reduced glutathione, and TNFα levels, respectively; (3) luminal neutrophil infiltration and tissue myeloperoxidase activity; (4) functional impairment of exercise endurance; and (5) airspace enlargement, in both preventive and interventional dosing protocols. Notably, the effects were shown to last for 24 h at the greater 100-μg/kg dose, and the 1-week-delayed administration was also capable of attenuating the development of emphysema.

Conclusions

CDSO3 is a novel, potent, long-acting, nonpeptidic macromolecule that inhibits HSE/CSE-induced elastolysis, oxidation, and inflammation in the lung and thereby attenuates the development of emphysema in rats, in both preventive and interventional manners, when administered locally to the lung.     

Expression of TNF-α and VEGF in the esophagus of portal hypertensive rats

AIM: To investigate the expression of tumor necrosis factor-alpha (TNF-α) and vascular endothelial growth factor (VEGF) in the development of esophageal varices in portal hypertensive rats. METHODS: Thirty male Sprague-Dawley (SD) rats in the model group in which a two-stage ligation of portal vein plus ligation of the left adrenal vein was performed, were divided into three subgroups (M7, M14, and M21) in which the rats were kiued on the seventh day, the 14^th d and the 21 d after the complete portal ligation. Thirty male SD rats, which underwent the sham operation in the control group, were also separated into three subgroups (C7, C14 and C21) corresponding to the models. The expression of TNF-α and VEGF in the esophagus of all the six subgroups of rats were measured with immunohistochemical SP technique. RESULTS: The portal pressure in the three model subgroups was significantly higher than that in the corresponding control subgroups (23.82&#177;1.83 vs 11.61&#177;0.86 cmH2O, 20.90&#177;3.27 vs 11.43&#177;1.55 cmH2O and 20.68&#177;2.27 vs 11.87&#177;0.79 cmH2O respectively, P&lt;0.01), as well as the number (9.3&#177;1.6 vs 5.1&#177;0.8, 11.1&#177;0.8 vs 5.4&#177;1.3 and 11.7&#177;1.5 vs 5.2&#177;1.1 respectively, P&lt;0.01) and the total vascular area (78 972.6&#177;3 527.8 vs 12 993.5&#177;4 994.8 um^2, 107 207.5&#177;4 6461.4 vs 11 862.6&#177;5 423.2 um^2 and 110 241.4&#177;49 262.2 vs 11 973.7&#177;3 968.5 um^2 respectively, P&lt;0.01) of submucosal veins in esophagus. Compared to the corresponding controls, the expression of TNF-α and VEGF in M21 was significantly higher (2.23&#177;0.30 vs 1.13&#177;0.28 and 1.65&#177;0.38 vs 0.56&#177;0.30 for TNF-α and VEGF respectively, P &lt;0.01), whereas there was no difference in M7 (1.14&#177;0.38 vs 1.06&#177;0.27 and 0.67&#177;0.35 vs 0.50&#177;0.24 for TNF-α and VEGF respectively, P&gt;0.05) and M14 (1.20&#177;0.25 vs 1.04&#177;0.26 and 0.65&#177;0.18 vs 0.53&#177;0.25 for TNF-α and VEGF respectively, P&gt;0.05). And the expression of TNF-α and VEGF in M21 was significantly higher than that in M7 (2.23&#177;0.30 vs 1.14&#177;0.38 and 1.65&#177;0.38 vs 0.67&#177;0.35 for TNF-α and VEGF respectively, P&lt;0.01) and M14 (2.23&#177;0.30 vs 1.20&#177;0.25 and 1.65&#177;0.38 vs 0.65&#177;0.18 for TNF-α and VEGF respectively, P&lt;0.01), but there was no difference between M7 and M14 (1.14&#177;0.38 vs 1.20&#177;0.25 and 0.67&#177;0.35 vs 0.65&#177;0.18 for TNF-α and VEGF respectively, P &gt;0.05). CONCLUSION: In the development of esophageal varices in portal hypertensive rats, increased TNF-α and VEGF may be not an early event, and probably play a role in weakening the esophageal wall and the rupture of esophageal varices.     

Expression of TNF-α and VEGF in the esophagus of portal hypertensive rats

AIM: To investigate the expression of tumor necrosis factor-alpha (TNF-α) and vascular endothelial growth factor (VEGF) in the development of esophageal varices in portal hypertensive rats. METHODS: Thirty male Sprague-Dawley (SD) rats in the model group in which a two-stage ligation of portal vein plus ligation of the left adrenal vein was performed, were divided into three subgroups (M7, M14, and M21) in which the rats were kiued on the seventh day, the 14th d and the 21 d after the complete portal ligation. Thirty male SD rats, which underwent the sham operation in the control group, were also separated into three subgroups (C7, C14 and C21) corresponding to the models. The expression of TNF-α and VEGF in the esophagus of all the six subgroups of rats were measured with immunohistochemical SP technique. RESULTS: The portal pressure in the three model subgroups was significantly higher than that in the corresponding control subgroups (23.82±1.83 vs 11.61±0.86 cmH2O, 20.90±3.27 vs11.43±1.55 cmH2O and 20.68±2.27 vs 11.87±0.79 cmH2O respectively, vs P<0.01), as well as the number (9.3±1.6 vs 5.1?.8, 11.1±0.8 vs 5.4±1.3 and 11.7±1.5 vs 5.2?.1 respectively, P<0.01) and the total vascular area (78 972.6±3 527.8 vs 12 993.5±4 994.8 μm2, 107 207.5±4 6461.4 vs 11 862.6±5 423.2 μm2 and 110 241.4±49 262.2 vs 11 973.7±3 968.5 μm2 respectively, P<0.01) of submucosal veins in esophagus. Compared to the corresponding controls, the expression of TNP-α and VEGF in M21 was significantly higher (2.23±0.30 vs 1.13±0.28 and 1.65±0.38 vs 0.56±0.30 for TNF-α and VEGF respectively, P <0.01), whereas there was no difference in M7(1.14±0.38 vs 1.06±0.27 and 0.67±0.35 vs 0.50±0.24 for TNPa and VEGF respectively, P>0.05) and M14 (1.20±0.25 vs 1.04±0.26 and 0.65±0.18 vs 0.53±0.25 for TNF-α and VEGF respectively, P>0.05). And the expression of TNF-α and VEGF in M21 was significantly higher than that in M7 (2.23±0.30 vs1.14±0.38 and 1.65±0.38 vs 0.67±0.35 for TNF-α and VEGF respectively, P<0.01) and M14(2.23±0.30 vs 1.20±0.25 and 1.65±±0.38 vs 0.65±0.18 for TNF-a and VEGF respectively, P<0.01), but there was no difference between M7and M14(1.14±0.38 vs1.20±0.25 and 0.67±0.35 vs 0.65±0.18 for TNF-α and VEGF respectively, P>0.05). CONCLUSION: In the development of esophageal varices in portal hypertensive rats, increased TNF-α and VEGF may be not an early event, and probably play a role in weakening the esophageal wall and the rupture of esophageal varices.     

Transmission Dynamics of Extended-Spectrum β-lactamase-Producing Enterobacteriaceae in the Tertiary Care Hospital and the Household Setting

Background.?Studies about transmission rates of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae in hospitals and households are scarce. Methods.?Eighty-two index patients with new carriage of ESBL-producing Escherichia coli (ESBL-Ec; n?=?72) or ESBL-producing Klebsiella pneumoniae (ESBL-Kp; n?=?10) and their hospital (n?=?112) and household (n?=?96) contacts were studied prospectively from May 2008 through September 2010. Isolates were phenotypically and molecularly characterized (sequencing of bla genes, repetitive extragenic palindromic polymerase chain reaction, pulse-field gel electrophoresis, and multilocus sequence typing). Transmission was defined as carriage of a clonally-related ESBL producer with identical bla(ESBL) gene(s) in the index patient and his or her contact(s). Results.?CTX-M-15 was the most prevalent ESBL in ESBL-Ec (58%) and ESBL-Kp (70%) in the index patients. Twenty (28%) ESBL-Ec isolates were of the hyperepidemic clone ST131. In the hospital, transmission rates were 4.5% (ESBL-Ec) and 8.3% (ESBL-Kp) and the incidences of transmissions were 5.6 (Ec) and 13.9 (Kp) per 1000 exposure days, respectively. Incidence of ESBL-Kp hospital transmission was significantly higher than that of ESBL-Ec (P?相似文献   

Is the First of the Two Born Saved? A Rare and Dramatic Case of Double Placental Damage from SARS-CoV-2

The current coronavirus pandemic has affected, in a short time, various and different areas of medicine. Among these, the obstetric field has certainly been touched in full, and the knowledge of the mechanisms potentially responsible for placental damage from SARS-CoV-2 occupy a certain importance. Here we present here a rare case of dichorionic twins born at 30 weeks and 4 days of amenorrhea, one of whom died in the first few hours of life after placental damages potentially related to SARS-CoV-2. We also propose a brief review of the current literature giving ample emphasis to similar cases described.     

Expression of the proliferation-associated Ki-67 antigen of transferrin receptors and of DNA polymeraseα in human tumour lines: implications for in vitro chemoresistance

Summary To compare the time course of in vitro expression of various proliferation-associated markers including Ki-67 antigen, transferrin receptors (TfR), and DNA polymerase , six human tumour cell lines of different histological origin were studied under defined conditions. Proliferation markers were demonstrated by peroxidase/anti-peroxidase staining using specific monoclonal antibodies, and their expression was compared to results obtained from [³H]-thymidine incorporation assays and cell counting. Expression of all proliferation markers began to increase during the lag phase, and occurred earlier than elevations of [³H]dT incorporation and cell numbers were recorded. Maximum expression was observed before cell growth reached plateau phase. The time courses of expression of DNA polymerase and Ki-67 were almost identical. The closest correlation of [³H]dT incorporation with time course of expression of proliferation-associated markers was observed, when intranuclear staining of DNA polymerase was analysed. TfR were expressed earlier than the polymerase and Ki-67. Since TfR were also found at remarkable levels in resting cells, they seem less proliferation-specific than Ki-67 and DNA polymerase. While in rapidly growing cell lines more than 95% of the cells expressed Ki-67, TfR, and more than 75% DNA polymerase in cell nuclei, a malignant melanoma and a pleural mesothelioma line displayed fewer than 35% of cells stained for DNA polymerase in cell nuclei during log phase. Determination of growth fractions by monoclonal antibodies may thus contribute to the prediction of chemoresistance by identifying quiescent cells that are not sensitive to S-phasespecific drugs.Abbreviation TfR transferrin receptors