The effects of ATP on the contractions of rat and mouse fast skeletal muscle

Introduction: The aim of this study was to compare the effects of adenosine-5'-triphosphate (ATP) and adenosine on the contractility of rodent extensor digitorum longus (EDL) muscle at normal and low temperatures. Methods: Contractions of rat and mouse isolated EDL were induced by either electrical stimulation (ES) or exogenous carbachol and recorded in the presence of ATP or adenosine (both at 100 μM). Results: ATP at all temperatures caused a decrease of the contractions induced by carbachol in rat and mouse EDL and ES-induced contractions in rat EDL, while it potentiated the ES-induced contractions of mouse EDL. Adenosine reduced the contractility of rat and mouse EDL evoked by ES and did not affect the carbachol-induced contractions of rat and mouse EDL at any temperature. Discussion: Under various temperature conditions, ATP inhibits pre- but potentiates postsynaptic processes in the mouse EDL; in the rat EDL ATP causes only inhibition of neuromuscular conduction. Muscle Nerve 59:509–516, 2019     

New approaches to prognosis of risk of development of gastropathies induced by nonsteroid anti-inflammatory agents

A pharmacological test with indomethacin is suggested for predicting the risk of NSAID-induced gastropathy. It is shown that patients with diagnoses of rheumatoid arthritis and osteoarthrosis can be divided into two groups with respect to the indomethacin test--"vulnerable" and "resistant", characterized by a high and low risk of NAIDS-induced gastropathy development, respectively. The proposed index of resistance to this disorder, together with the glutathione redox buffer test index, can be used as reliable criteria for predicting the NSAID-induced gastropathy.     

Contractile activity of isolated myometrium from pregnant women with chronic specific urogenital infections

Contractile activity of the isolated myometrium from pregnant women with mycoplasma, chlamydial, and mixed mycoplasma-chlamydial infections of the urogenital system was studied in vitro by pharmacological methods. The amplitude of uterine contractions induced by oxytocin and prostaglandin F2a decreased in women with mycoplasma infection, but increased during chlamydial and mixed infections. These data can help to predict pregnancy complications in women with specific urogenital infections.     

Contractile activity of human greater saphenous vein mediated by P2-receptors

In vitro experiments were carried out to measure the contractile responses to P₂-receptor agonists in the greater saphenous vein isolated from patients with obliterating vascular atherosclerosis and varicose veins of the legs. In patients with varicose veins, the contractile responses of the greater saphenous vein to ATP, ,-methylene-ATP, and UTP were significantly lower than in patients with obliterating atherosclerosis, while the responses to ADP, adenosine, and 2-methylthio-ATP were similar in both groups. These data attest to the presence of P₂-receptor-mediated contraction component in the greater saphenous vein, which are pronouncedly weakened during varicose disease.     

Association between High Diffusion-Weighted Imaging-Derived Functional Tumor Burden of Peritoneal Carcinomatosis and Overall Survival in Patients with Advanced Ovarian Carcinoma

ObjectiveTo investigate the association between functional tumor burden of peritoneal carcinomatosis (PC) derived from diffusion-weighted imaging (DWI) and overall survival in patients with advanced ovarian carcinoma (OC).Materials and MethodsThis prospective study was approved by the local research ethics committee, and informed consent was obtained. Fifty patients (mean age ± standard deviation, 57 ± 12 years) with stage III–IV OC scheduled for primary or interval debulking surgery (IDS) were recruited between June 2016 and December 2021. DWI (b values: 0, 400, and 800 s/mm²) was acquired with a 16-channel phased-array torso coil. The functional PC burden on DWI was derived based on K-means clustering to discard fat, air, and normal tissue. A score similar to the surgical peritoneal cancer index was assigned to each abdominopelvic region, with additional scores assigned to the involvement of critical sites, denoted as the functional peritoneal cancer index (fPCI). The apparent diffusion coefficient (ADC) of the largest lesion was calculated. Patients were dichotomized by immediate surgical outcome into high- and low-risk groups (with and without residual disease, respectively) with subsequent survival analysis using the Kaplan-Meier curve and log-rank test. Multivariable Cox proportional hazards regression was used to evaluate the association between DWI-derived results and overall survival.ResultsFifteen (30.0%) patients underwent primary debulking surgery, and 35 (70.0%) patients received neoadjuvant chemotherapy followed by IDS. Complete tumor debulking was achieved in 32 patients. Patients with residual disease after debulking surgery had reduced overall survival (p = 0.043). The fPCI/ADC was negatively associated with overall survival when accounted for clinicopathological information with a hazard ratio of 1.254 for high fPCI/ADC (95% confidence interval, 1.007–1.560; p = 0.043).ConclusionA high DWI-derived functional tumor burden was associated with decreased overall survival in patients with advanced OC.     

Engineering analysis of aortic wall stress and root dilatation in the V-shape surgery for treatment of ascending aortic aneurysms

Open in a separate window OBJECTIVESThe study objective was to evaluate the aortic wall stress and root dilatation before and after the novel V-shape surgery for the treatment of ascending aortic aneurysms and root ectasia.METHODSClinical cardiac computed tomography images were obtained for 14 patients [median age, 65 years (range, 33–78); 10 (71%) males] who underwent the V-shape surgery. For 10 of the 14 patients, the computed tomography images of the whole aorta pre- and post-surgery were available, and finite element simulations were performed to obtain the stress distributions of the aortic wall at pre- and post-surgery states. For 6 of the 14 patients, the computed tomography images of the aortic root were available at 2 follow-up time points post-surgery (Post 1, within 4 months after surgery and Post 2, about 20–52 months from Post 1). We analysed the root dilatation post-surgery using change of the effective diameter of the root at the two time points and investigated the relationship between root wall stress and root dilatation.RESULTSThe mean and peak max-principal stresses of the aortic root exhibit a significant reduction, P=0.002 between pre- and post-surgery for both root mean stress (median among the 10 patients presurgery, 285.46 kPa; post-surgery, 199.46 kPa) and root peak stress (median presurgery, 466.66 kPa; post-surgery, 342.40 kPa). The mean and peak max-principal stresses of the ascending aorta also decrease significantly from pre- to post-surgery, with P=0.004 for the mean value (median presurgery, 296.48 kPa; post-surgery, 183.87 kPa), and P=0.002 for the peak value (median presurgery, 449.73 kPa; post-surgery, 282.89 kPa), respectively. The aortic root diameter after the surgery has an average dilatation of 5.01% in total and 2.15%/year. Larger root stress results in larger root dilatation.CONCLUSIONSThis study marks the first biomechanical analysis of the novel V-shape surgery. The study has demonstrated significant reduction in wall stress of the aortic root repaired by the surgery. The root was able to dilate mildly post-surgery. Wall stress could be a critical factor for the dilatation since larger root stress results in larger root dilatation. The dilated aortic root within 4 years after surgery is still much smaller than that of presurgery.     

Provision of an out-of-hours blood banking service at a satellite hospital without blood bank staff

With limited health care resources and financial constraints, many hospitals have to reduce their service. Computer crossmatching has been accepted as a safe crossmatching procedure for patients without clinically significant alloantibodies. We report here a novel way of providing an out-of-hours blood banking service at a satellite hospital. The system is easy to introduce and can provide a safe transfusion service to small hospitals without stationing blood banking staff at these hospitals after regular working hours.     

T-cell intravascular lymphomatosis (angiotropic large cell lymphoma): association with Epstein–Barr viral infection

Amniotic fluid bacterial infection is an occasional cause of second trimester septic abortion. We describe an autolysis-related histological artifact, umbilical cord ‘pseudo-vasculitis’, which can erroneously implicate amniotic bacterial infection in fetal death. Clinicopathological features of 13 second trimester fetal deaths with umbilical cord pseudo-vasculitis are reported. In four cases (31%), an incorrect pathological diagnosis of umbilical vasculitis had initially been rendered. Umbilical cords from five cases of pseudo-vasculitis and one comparison fetus (18-week septic abortion with true umbilical vasculitis), were studied with chloroacetate esterase and with immunohistochemical staining for myeloperoxidase, muscle-specific actin (HHF35) and smooth muscle actin. Histologically, umbilical pseudo-vasculitis exhibited numerous small, rounded, degenerating cells with irregular, multilobed nuclei (closely resembling neutrophils) located within the umbilical vessel wall. Immunohistochemical studies demonstrated that all cells resembling neutrophils were of smooth muscle origin. Moderate to severe fetal autolysis was present in all cases of umbilical pseudo-vasculitis, suggesting that this finding represents autolysis of umbilical vascular smooth muscle secondary to post mortem fetal retention. Vascular smooth muscle in other fetal and placental locations did not demonstrate the finding, suggesting that this striking degenerative artifact of smooth muscle is restricted to the umbilical cord.