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81.
Sawsan A. Oran 《Pharmaceutical biology》2013,51(4):296-299
Fifteen different plants representing different species, genera and families were used to test the effect of their aqueous extracts on tumor inhibition with a rapid, inexpensive, safe, animal sparing technique, and statistically reliable prescreen for in vivo murine leukemia antitumor activity, which is known as potato disc technique. The inoculum used contains the extract with the bacterium (Agrobacterium tumefaciens) that was known to cause crown gall tumor to different plant species especially dicotyledons and some gymnosperms. After 12 to 21 days of incubation the tumors appeared and were counted, and the maximum inhibition was then calculated. Thirteen species out of fifteen showed a good antitumor effect, and three of them showed a maximum inhibition of 80%. More experiments are necessary to determine the exact mechanism of action. 相似文献
82.
Mahmoud Shaban El‐Neweshy 《International journal of experimental pathology》2013,94(2):109-114
All reports of doxycycline‐induced cardiomyopathy to date have been limited to accidental oral poisoning in calves. Therefore, the current study investigated the cardiomyotoxic effect of experimental doxycycline overdose in rats as a toxicity model which could be monitored using histopathological and biochemical assays. A total of 38‐week‐old male Wistar rats were divided into three groups consisting of 10 each. The first group was an untreated control group (D0), and the second group (D5) received doxycycline hyclate 25 mg/kg intragastrically twice daily (8 AM and 8 PM), which is 5‐fold higher than the standard dose. The third group (D10) received 50 mg/kg intragastrically twice daily (8 AM and 8 PM), which is 10‐fold higher than the standard dose. The dose continued for 10 consecutive days and revealed that the doxycycline toxicity was dose dependent. Mortality was recorded in the D10 group only (30%). The D5 rats exhibited minimal skeletal muscle injury and slight but significant increases in the skeletal muscle damage indicators creatine kinase (CK) and aspartate aminotransferase (AST) compared to controls. The cardiac muscle of the D5 rats was histologically normal, and the D5 rats also exhibited normal levels of troponin I (cTnI), an indicator of cardiac muscle damage. In contrast, the D10 rats displayed cardiomyopathy, as well as significant increases in the muscle enzymes alanine aminotransferase (ALT), AST and CK and the cardiac damage indicator cTnI compared to control and D5 groups. Pulmonary lesions were observed in the D10 rats, primarily cardiac lesion‐related alveolar heart failure cells. Thus the present study is the first to demonstrate that oral doxycycline poisoning (10 times the therapeutic dose)‐induced cardiomyopathy is not limited to calves and could occur without any predisposing factors. 相似文献
83.
Activation of central GABAB receptors offsets the cyclosporine counteraction of endotoxic cardiovascular outcomes in conscious rats
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Marwa Y. Sallam Sahar M. El‐Gowilly Abdel‐Galil A. Abdel‐Galil Mahmoud M. El‐Mas 《Fundamental & clinical pharmacology》2018,32(5):485-498
We have previously shown that cyclosporine (CSA) counteracts cardiovascular manifestations induced by endotoxemia (lipopolysaccharide, LPS) such as hypotension and cardiac autonomic dysfunction in conscious rats. In this study, we investigated whether the facilitation of central γ‐amino butyric acid (GABA) neurotransmission blunts these favorable influences of CSA. The LPS‐CSA interaction was determined in the absence and presence of drugs that activate GABAA or GABAB receptors or elevate synaptic GABA levels in the central nervous system. The consequent i.v. administration of CSA (10 mg/kg) blunted the LPS‐evoked hypotension, tachycardia, and reductions in time‐ and frequency‐domain indices of heart rate variability (measures of cardiac autonomic control) evoked by LPS (10 mg/kg i.v.). The ability of CSA to reverse the LPS effects disappeared in rats treated intracisternally (i.c.) with baclofen (selective GABAB agonist, 2 μg/rat) but not muscimol (selective GABAA agonist, 1 μg/rat), indicating a preferential compromising action for central GABAB receptors on the advantageous effects of CSA. Moreover, the improvement by CSA of LPS‐evoked cardiovascular derangements was also eliminated after concurrent i.c. administration of vigabatrin (GABA transaminase inhibitor, 200 μg/rat) or tiagabine (GABA reuptake inhibitor, 100 μg/rat). These results demonstrate that the activation of central GABAB receptors either directly via baclofen or indirectly following interventions that boost GABA levels in central synapses counterbalances the rectifying action of CSA on endotoxemia. 相似文献
84.
85.
Nabil M. Abdel-Hamid Tarek K. Mahmoud Shimaa A. Abass Mamdouh M. El-Shishtawy 《Pathophysiology》2018,25(4):433-438
Hepatocellular carcinoma (HCC), represents more than 85% of liver cancers. The diagnosis of HCC may be delayed due to the absence of early, sensitive and specific biomarkers. This study was conducted to investigate whether the expression of thioredoxin (Trx) and glutaredoxin (Grx) is helpful for HCC diagnosis in an experimental model. Twenty male albino rats were equally divided into two groups (HCC and control). Hepatocarcinogenesis was performed by single intraperitoneal (i.p) injection of 200?mg/kg of diethylnitrosamine (DENA). Two weeks later, 0.05% of phenobarbital (PB) was supplied in the drinking water for other 14 weeks. HCC was diagnosed by measuring serum alpha-fetoprotein (AFP) level and histopathological examination. Our results found that hepatic indices alanine transaminase (ALT), aspartate transaminase (AST), total bilirubin were elevated but decreased total protein level. Lipid peroxidation was elevated through increasing hepatic content of MDA with decreased antioxidant parameters like hepatic SOD, CAT activities and GSH. The current study also found that Trx and Grx tissue genes were overexpressed in HCC group significantly, compared to control group. This study substantiated that increased expression of these enzymes may be predictive of outcomes in HCC. 相似文献
86.
Aims: The aim of this study was to explore the family members' determinant of the delay in seeking psychiatric care to patients diagnosed with psychosis. Methods: Qualitative semi-structured interviews were carried out with twenty-seven family members of patients with psychosis at psychiatric outpatient clinics in Amman, Jordan. Results: The findings revealed that perceived stigma and fears about being labelled are the main barriers to requesting early psychiatric health care. The participants cited many different reasons linked to finding help led to delay in seeking help in the early stages of the illness including misattribution of the cause and symptoms of mental illness, family and financial factors. Conclusions: The study highlights the importance of enhancing knowledge about the schizophrenia-related spectrum to ensure patients seek treatment in a more timely manner. 相似文献
87.
Three‐dimensional transesophageal echocardiography incremental value in a rare case of a bileaflet tricuspid valve
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Hani M. Mahmoud M.B.B.Ch M.Sc. F.A.S.E. Hossam Walley M.D. Hatem Hosny M.Sc. Magdi Yacoub F.R.C.S. F.R.S. 《Echocardiography (Mount Kisco, N.Y.)》2016,33(9):1438-1440
Detailed assessment of the tricuspid valve using two‐dimensional echocardiography is always challenging, as only two of three leaflets can be seen at a time. Three‐dimensional echocardiography can provide the enface view of the tricuspid valve that allows simultaneous visualization of all of the three leaflets. In a 42‐year‐old male patient scheduled for pulmonary endarterectomy, 3DTEE showed that the tricuspid valve is bileaflet, with one septal and another lateral leaflet. There were two commissures, one of them is anteriorly positioned and the other one is posterior. Our findings were confirmed intra‐operatively by direct surgical visualization of the tricuspid valve. 相似文献
88.
89.
R. El‐Sayed Mahmoud Marie G. A. K. El‐Sayed F. M. Attia A. H. A. Gomaa 《Clinical and experimental dermatology》2021,46(1):153-156
Alopecia areata (AA) is a recurrent, immune‐mediated, hair‐loss disorder. It is associated with other autoimmune disorders that carry a high risk of cardiovascular disease (CVD). However, there is a lack of reports on the association of cardiovascular comorbidities and AA. Cardiac troponin I is a biomarker of myocardial ischaemia and inflammation, while N‐terminal pro‐B‐type natriuretic peptide is used in the diagnosis of congestive heart failure. This study was conducted to assess the serum level of both markers by ELISA in 44 patients with AA compared with 44 healthy controls (HCs). None of the participants had CVD, CVD risk factors or other diseases associated with elevation of either marker. The study revealed that serum levels of both markers were significantly higher in patients with AA compared with HCs (P < 0.001). The inflammatory milieu encountered in AA may be associated with subtle myocardial inflammation that causes elevation of levels of both of these cardiac markers. 相似文献