59 research outputs found
The Effect of Praziquantel on Patterns of Schistosoma mansoni Eggshell Hatching Breaks
The break of the eggshell formed by water- and praziquantel (PZQ)-induced hatching of Schistosoma mansoni eggs was observed by scanning electron microscopy. The break most frequently formed on the long axis of the eggshell opposite the spine, and less frequently along spine side, parallel or oblique to the long axis of the lateral side of the egg-shell. An outwardly-curled lip of shell lined the external margins of the hatching orifice. The shell itself was of uniform thickness and fairly smooth. No significant difference was observed in the position breaks between water- and PZQ-hatched eggs. However, PZQ hatching produced smaller hatching orifices and the miracidium frequently failed to escape
Influence of long term administration of tofogliflozin on chronic inflammation of visceral adipose tissue in mice with obesity induced by a high-fat diet.
We previously found that senescence of cluster of differentiation 4 (CD4) T cells is accelerated in the visceral adipose tissue (VAT) of mice with diet-induced obesity (DIO) due to a high-fat diet (HFD), and that these senescent-associated T cells cause chronic inflammation of visceral adipose tissue through secretion of osteopontin, provoking systemic insulin resistance. In this study, we examined whether the development of chronic inflammation and senescence-associated T cells in VAT of DIO mice was improved by long-term weight loss after switching to normal chow (NC) or by administration of a sodium glucose cotransporter 2 inhibitor (tofogliflozin). Wild-type mice were fed an HFD for 26 weeks from 4 weeks old. At 30 weeks of age, half of these DIO mice were switched to NC with or without 0.005% tofogliflozin for 38 weeks. The other mice remained on the HFD with or without 0.005% tofogliflozin for 38 weeks. When DIO mice were switched to NC, their weight decreased to that of mice kept on NC since weaning. After 38 weeks (68 weeks of age), chronic inflammation of the VAT subsided with disappearance of senescence-associated T cells. In the HFD groups, the carbohydrate intake per mouse was half or less of that in the NC group, and urinary glucose excretion by the effect of tofogliflozin was lower in the HFD mice than in the NC mice. Mice that remained on the HFD showed no improvement in chronic inflammation in VAT, possibly because urinary glucose excretion was not sufficiently promoted by tofogliflozin due to the low carbohydrate intake. Thus, no improvement in glucose metabolism or weight loss was observed in these mice
Therapeutic Targets for DOX-Induced Cardiomyopathy: Role of Apoptosis vs. Ferroptosis
Doxorubicin (DOX) is the most widely used anthracycline anticancer agent; however, its cardiotoxicity limits its clinical efficacy. Numerous studies have elucidated the mechanisms underlying DOX-induced cardiotoxicity, wherein apoptosis has been reported as the most common final step leading to cardiomyocyte death. However, in the past two years, the involvement of ferroptosis, a novel programmed cell death, has been proposed. The purpose of this review is to summarize the historical background that led to each form of cell death, focusing on DOX-induced cardiotoxicity and the molecular mechanisms that trigger each form of cell death. Furthermore, based on this understanding, possible therapeutic strategies to prevent DOX cardiotoxicity are outlined. DNA damage, oxidative stress, intracellular signaling, transcription factors, epigenetic regulators, autophagy, and metabolic inflammation are important factors in the molecular mechanisms of DOX-induced cardiomyocyte apoptosis. Conversely, the accumulation of lipid peroxides, iron ion accumulation, and decreased expression of glutathione and glutathione peroxidase 4 are important in ferroptosis. In both cascades, the mitochondria are an important site of DOX cardiotoxicity. The last part of this review focuses on the significance of the disruption of mitochondrial homeostasis in DOX cardiotoxicity
Bleeding sites and treatment strategies for cardiac tamponade by catheter ablation requiring thoracotomy: risks of catheter ablation in patients with left atrial diverticulum
Abstract Background There is insufficient information regarding the bleeding sites and surgical strategies of cardiac tamponade during catheter ablation for atrial fibrillation (AF). Case presentation Of the five patients with cardiac tamponade, three required surgical intervention and two required pericardiocentesis. In the first case of three cardiac tamponades requiring surgical intervention, considering that the peripheral route was used, the catecholamines did not reach the heart, and due to unstable vital signs, venoarterial extracorporeal membrane oxygenation (VA-ECMO) was inserted. No bleeding point was identified, but a thrombus had spread around the left atrium (LA) with diverticulum. Hemostasis was achieved with adhesives placed around the LA under on-pump beating. In the second case, pericardiocentesis was performed, but the patient showed heavy bleeding and unstable vital signs. Thus, VA-ECMO was inserted. Heavy bleeding was expected, and safety was enhanced by attaching a reservoir to the VA-ECMO. The bleeding point was found between the left upper pulmonary artery and LA under cardiac arrest to obtain a good surgical view for suturing repair. In the third case, the LA diverticulum was damaged. Pericardiocentesis resulted in stable vitals, but sustained bleeding was present. A bleeding point was found at the LA diverticulum, and suture repair under on-pump beating was performed. Conclusions When cardiac tamponade occured in any patient with LA diverticulum, treatment could not be completed with pericardiocentesis alone, and thoracotomy was likely to be necessary. If the bleeding point could be confirmed, suturing technique is a more reliable surgical strategy than adhesive alone that leads to pseudoaneurysm. If the bleeding point is unclear, it is important to confirm the occurrence of LA diverticulum using a preoperative CT, and if confirmed, cover it with adhesive due to a high possibility of diverticulum bleeding. The necessity of CPB should be determined based on whether these operations can be completed while maintaining vital stability
Laminar flow ventilation system to prevent airborne infection during exercise in the COVID-19 crisis: A single-center observational study.
Particulate generation occurs during exercise-induced exhalation, and research on this topic is scarce. Moreover, infection-control measures are inadequately implemented to avoid particulate generation. A laminar airflow ventilation system (LFVS) was developed to remove respiratory droplets released during treadmill exercise. This study aimed to investigate the relationship between the number of aerosols during training on a treadmill and exercise intensity and to elucidate the effect of the LFVS on aerosol removal during anaerobic exercise. In this single-center observational study, the exercise tests were performed on a treadmill at Running Science Lab in Japan on 20 healthy subjects (age: 29±12 years, men: 80%). The subjects had a broad spectrum of aerobic capacities and fitness levels, including athletes, and had no comorbidities. All of them received no medication. The exercise intensity was increased by 1-km/h increments until the heart rate reached 85% of the expected maximum rate and then maintained for 10 min. The first 10 subjects were analyzed to examine whether exercise increased the concentration of airborne particulates in the exhaled air. For the remaining 10 subjects, the LFVS was activated during constant-load exercise to compare the number of respiratory droplets before and after LFVS use. During exercise, a steady amount of particulates before the lactate threshold (LT) was followed by a significant and gradual increase in respiratory droplets after the LT, particularly during anaerobic exercise. Furthermore, respiratory droplets ≥0.3 μm significantly decreased after using LFVS (2120800±759700 vs. 560 ± 170, p<0.001). The amount of respiratory droplets significantly increased after LT. The LFVS enabled a significant decrease in respiratory droplets during anaerobic exercise in healthy subjects. This study's findings will aid in exercising safely during this pandemic
Pharmacokinetics of a single inhalation of hydrogen gas in pigs.
The benefits of inhaling hydrogen gas (H2) have been widely reported but its pharmacokinetics have not yet been sufficiently analyzed. We developed a new experimental system in pigs to closely evaluate the process by which H2 is absorbed in the lungs, enters the bloodstream, and is distributed, metabolized, and excreted. We inserted and secured catheters into the carotid artery (CA), portal vein (PV), and supra-hepatic inferior vena cava (IVC) to allow repeated blood sampling and performed bilateral thoracotomy to collapse the lungs. Then, using a hydrogen-absorbing alloy canister, we filled the lungs to the maximum inspiratory level with 100% H2. The pig was maintained for 30 seconds without resuming breathing, as if they were holding their breath. We collected blood from the three intravascular catheters after 0, 3, 10, 30, and 60 minutes and measured H2 concentration by gas chromatography. H2 concentration in the CA peaked immediately after breath holding; 3 min later, it dropped to 1/40 of the peak value. Peak H2 concentrations in the PV and IVC were 40% and 14% of that in the CA, respectively. However, H2 concentration decay in the PV and IVC (half-life: 310 s and 350 s, respectively) was slower than in the CA (half-life: 92 s). At 10 min, H2 concentration was significantly higher in venous blood than in arterial blood. At 60 min, H2 was detected in the portal blood at a concentration of 6.9-53 nL/mL higher than at steady state, and in the SVC 14-29 nL/mL higher than at steady state. In contrast, H2 concentration in the CA decreased to steady state levels. This is the first report showing that inhaled H2 is transported to the whole body by advection diffusion and metabolized dynamically
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