Cure Modification Effected by Cycloalkylthioamines in the Vulcanization of NR Accelerated by Thiocarbamyl Sulfenamides and Dibenzothiazyl Disulfide

1988 ◽  
Vol 61 (5) ◽  
pp. 760-782 ◽  
Author(s):  
Prasanta Kumar Das ◽  
Rabindra Nath Datta ◽  
Dipak Kumar Basu

Abstract The role of the thioamines as retardera in the vulcanization of NR accelerated by the binary system comprising thiocarbamyl sulfenamide and MBTS has been investigated. Several thioamines, namely, cyclohexyl thiomorpholine (CM), cyclohexyl thiopiperidine (CP), cyclohexyl thiodibutylamine (CDBA), cyclohexyl thiodiphenylamine (CDPA), cyclohexyl thiodiisopropyl amine (CDIPA), dicyclohexyl dithiopiperazine (DCDPz), cyclohexyl thiodiethylamine (CDEA), and cyclohexyl thiodibenzopyrrole (CDBP) had been selected for the study. It has been observed that these thioamines provide better cure retardation than CTP and almost in all the cases, cure rates and torque values of the resulting vulcanizates are increased. It is further noticed that the vulcanizates obtained from the stocks containing CDEA, CDBP, and CDPA exhibit notably more heat and age resistance than those obtained from CTP. Some hplc studies were made to understand cure activation. MBT and N-oxydiethylenethiocarbamyl benzothiazole disulfide (OTBD) seem to activate cure, especially in the presence of thioamines. Antioxidants like di-β-napthyl-p-phenylenediamine (DNPD) and N-phenyl-N-sopropyl-p-phenylenediamine (PIPPD), when present in the respective stocks, further enhance both heat and age resistance properties of the resulting vulcanizates.

Life ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 365
Author(s):  
Carina Colturato-Kido ◽  
Rayssa M. Lopes ◽  
Hyllana C. D. Medeiros ◽  
Claudia A. Costa ◽  
Laura F. L. Prado-Souza ◽  
...  

Acute lymphoblastic leukemia (ALL) is an aggressive malignant disorder of lymphoid progenitor cells that affects children and adults. Despite the high cure rates, drug resistance still remains a significant clinical problem, which stimulates the development of new therapeutic strategies and drugs to improve the disease outcome. Antipsychotic phenothiazines have emerged as potential candidates to be repositioned as antitumor drugs. It was previously shown that the anti-histaminic phenothiazine derivative promethazine induced autophagy-associated cell death in chronic myeloid leukemia cells, although autophagy can act as a “double-edged sword” contributing to cell survival or cell death. Here we evaluated the role of autophagy in thioridazine (TR)-induced cell death in the human ALL model. TR induced apoptosis in ALL Jurkat cells and it was not cytotoxic to normal peripheral mononuclear blood cells. TR promoted the activation of caspase-8 and -3, which was associated with increased NOXA/MCL-1 ratio and autophagy triggering. AMPK/PI3K/AKT/mTOR and MAPK/ERK pathways are involved in TR-induced cell death. The inhibition of the autophagic process enhanced the cytotoxicity of TR in Jurkat cells, highlighting autophagy as a targetable process for drug development purposes in ALL.


2005 ◽  
Vol 13 (2) ◽  
pp. 172-174 ◽  
Author(s):  
Rishen Naidoo ◽  
Anu Reddi

The emergence of multidrug-resistant tuberculosis poses a serious challenge to traditional drug therapy. In view of the relapse rate of up to 50% following medical management, there has been renewed interest in the role of surgery for this problem. We report our experience with lung resection for this condition. Over a 5-year period, resection was performed in 23 patients who were diagnosed with multidrug resistance after completing a course of standard chemotherapy and at least 3 months of second-line therapy. Pneumonectomy was performed in 17 patients and lobectomy in 6. There was no operative or postoperative mortality. Major complications developed in 4 patients (17.4%): 2 had post-pneumonectomy empyema and 2 underwent rethoracotomy for bleeding. Ten patients were sputum positive preoperatively, and only 1 remained positive after surgery. The patients were put on appropriate chemotherapy and followed up for 18 months. The cure rate was 95.6%. Pulmonary resection can be considered as an important adjunct to medical therapy in carefully selected patients: those who have localized disease with adequate pulmonary reserve, or who have multiple previous relapses, or whose sputum remains positive after 4 to 6 months of appropriate medical treatment. Surgery offers high cure rates with acceptable morbidity and mortality.


Author(s):  
Inese Pontaga

The aim of our investigation was to determine the ratio of maximal torque values and the torques in the certain positions of range of movements (ROM) between hamstring (H) and quadriceps femoris (Q) muscles at medium and high velocity of movement in concentric (CC) and eccentric (ECC) action of hamstring muscles. The knee muscles of 15 amateur female short and middle distance runners were tested by the dynamometer system in the isokinetic movements with the angular velocity of 90º/s and 240º/s in CC and at the velocity of 90º/s in ECC H/ CC Q muscles contractions. The torque values produced by the muscles are detected at the different angular positions of the ROM with the step of 10º. The ratios of H/ Q muscles torques are calculated. The H/Q muscles maximal torques ratio is 0.51 ± 0.13 at the velocity of 90º/s in CC and 0.60 ± 0.09 in ECC H/ CC Q muscles contractions, and 0.59 ± 0.09 CC at the velocity of 240º/s. The H/Q maximal torques ratio and this ratio in the knee extreme extension and flexion at the ECC contraction of H is higher due to greater torques produced by the H in comparison with Q muscle. The H must be stronger to decelerate the thigh and lower leg extension in the late swing phase of running and to extend the hip in early stance phase to provide powerful sprint running and prevent the knee and H injury. The H/Q muscles torques ratio in extended knee positions are similar in medium (90º/s) and fast (240º/s) velocity of motions because CC action of H muscles cannot prevent extreme knee extension.


Neurosurgery ◽  
2019 ◽  
Vol 86 (Supplement_1) ◽  
pp. S36-S45 ◽  
Author(s):  
Bree Chancellor ◽  
Eytan Raz ◽  
Maksim Shapiro ◽  
Omar Tanweer ◽  
Erez Nossek ◽  
...  

Abstract Flow diverters (FDs) have changed the management of brain aneurysms; not only for complex aneurysms (giant, fusiform and blister) refractory to conventional therapies, but also for unruptured lesions previously managed by traditional surgical or coil-based endovascular methods. Since 2011 when the PipelineTM Embolization Device (Medtronic) was cleared by the Food and Drug Administration for adults with large or giant wide-neck intracranial aneurysms of the internal carotid artery proximal to the posterior communicating segment, the role of flow diversion for aneurysm treatment has expanded—supported by favorably low complication and high cure rates compared with alternative treatments. Here we review the key clinical trials and the long term outcomes that have demonstrated safety and efficacy of minimized porosity endoluminal devices in the treatment of cerebral aneurysms.


Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 5084
Author(s):  
Javier P. Gisbert

H. pylori infection is the main cause of gastritis, gastroduodenal ulcer disease, and gastric cancer. Fluoroquinolones such as levofloxacin, or more recently moxifloxacin or sitafloxacin, are efficacious alternatives to standard antibiotics for H. pylori eradication. The aim of the present review is to summarize the role of quinolone-based eradication therapies, mainly focusing on the optimization strategies aimed to increase their efficacy. Several meta-analyses have shown that, after failure of a first-line eradication treatment, a levofloxacin-containing rescue regimen is at least equally effective, and better tolerated, than the generally recommended bismuth quadruple regimen. Compliance with the levofloxacin regimens is excellent, and the safety profile is favourable. Higher cure rates have been reported with longer treatments (>10–14 days), and 500 mg levofloxacin daily is the recommended dose. Adding bismuth to the standard triple regimen (PPI-amoxicillin-levofloxacin) has been associated with encouraging results. Unfortunately, resistance to quinolones is easily acquired and is increasing in most countries, being associated with a decrease in the eradication rate of H. pylori. In summary, a quinolone (mainly levofloxacin)-containing regimen is an encouraging second-line (or even third-line) strategy, and a safe and simple alternative to bismuth quadruple therapy in patients whose previous H. pylori eradication therapy has failed.


2016 ◽  
Vol 851 ◽  
pp. 51-56 ◽  
Author(s):  
Martin Boháč ◽  
Radoslav Novotný ◽  
Jakub Tkacz ◽  
Miroslava Hajdúchová ◽  
Martin Palou ◽  
...  

The role of temperature of metakaolin/Portland cement binary system was studied by isothermal calorimetry. Sample with 50 % of metakaolin replacement were monitored at 30 °C, 40 °C, 50 °C and 60 °C. Structural and chemical characterization of hardened pastes was obtained by scanning electron and Raman microscopy. Paper deals with kinetics of main exothermal reactions during early hydration of the system. Activation energies were calculated for processes related to each exothermic peak. The nature of hydration products at different temperatures was revealed by microstructural studies.


2011 ◽  
Vol 29 (5) ◽  
pp. 495-503 ◽  
Author(s):  
Miguel A. Sanz ◽  
Francesco Lo-Coco

The advent of all-trans-retinoic acid (ATRA) and its combination with anthracycline-containing chemotherapy have contributed in the past 2 decades to optimize the antileukemic efficacy in acute promyelocytic leukemia (APL), leading to complete remission rates greater than 90%, virtual absence of resistance, and cure rates of nearly 80%. Recently reported studies from large cooperative trials have also shown that more rational delivery of treatment and improved outcomes may derive from the use of risk-adapted protocols. In particular, patients at higher risk of relapse (ie, those presenting with WBC > 10 × 109/L) seem to benefit from treatments that include cytarabine in the ATRA-plus-chemotherapy scheme, whereas patients with standard-risk disease can be successfully managed with less-intensive regimens that contain ATRA and anthracycline-based chemotherapy. After the outstanding results with arsenic trioxide (ATO) in the treatment of APL relapse, several experimental trials have been designed to explore the role of ATO in front-line therapy with the aim not only of minimizing the use of chemotherapy but also to reinforce standard ATRA-plus-chemotherapy regimens and additionally improve therapeutic efficacy. In this review article, we discuss most recent advances in the treatment of patients with newly diagnosed and relapsed APL.


2015 ◽  
Vol 1809 ◽  
pp. 7-12 ◽  
Author(s):  
Fei Teng ◽  
Julie D. Tucker

ABSTRACTMechanical property degradation due to an ordering phase transformation is a concern for alloys based on the Ni-Cr binary system (e.g., 690, 625), particularly in nuclear power applications, such as stream generator tubing, reactor pressure vessel and head control rod drive mechanism penetrations, where component lifetimes can exceed 40 years. In the present research, the disorder-order phase transformation has been studied in Ni-Cr model alloys with varying stoichiometry by experimental methods. In this paper, the effect of composition on ordering is characterized via X-ray diffraction.


2015 ◽  
Vol 7 (10) ◽  
pp. 5927-5937 ◽  
Author(s):  
Ting Zheng ◽  
Jiagang Wu ◽  
Dingquan Xiao ◽  
Jianguo Zhu ◽  
Xiangjian Wang ◽  
...  

2017 ◽  
pp. 195-226
Author(s):  
Anna Krajewska
Keyword(s):  

The article presents the concept of dramatography as being created by “writing drama”. The author treats drama as a fluid concept, historically variable, non-binary compared to theatre, establishing performative relations interwoven with other arts. Dramatography is a response to limitations resulting from the use of the concepts of adaptation, interpretation and intersemiotic translation in the former binary system in drama and theatre. Referring to Hans Ulrich Gumbrecht’s concept of “producing presence”, the author shows the role of manifesting oneself as a counterweight to meaning in the process through which dramatography emerges.


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