Comparative Effects of Heating and Fasting in Mice, with Particular Reference to Development of Sarcoma 180

Effects of heating and fasting, both alone and associated, have been studied in normal and Sarcoma 180 bearing mice. Heating reduced body weight and tumour mass and increased body temperature. Fasting reduced body weight, while tumour mass and body temperature were slightly affected. By associating heating and fasting a more marked decrease of body weight was produced than by each of the two factors involved, while effects on body temperature and on tumour mass were unchanged with respect to heating alone. 6-mercaptopurine was similar to heating in reducing body weight and tumour mass

Praziquantel: its use in control of schistosomiasis in sub-Saharan Africa and current research needs

Treatment with praziquantel (PZQ) has become virtually the sole basis of schistosomiasis control in sub-Saharan Africa and elsewhere, and the drug is reviewed here in the context of the increasing rate that it is being used for this purpose. Attention is drawn to our relative lack of knowledge about the mechanisms of action of PZQ at the molecular level, the need for more work to be done on schistosome isolates that have been collected recently from endemic areas rather than those maintained in laboratory conditions for long periods, and our reliance for experimental work mainly on Schistosoma mansoni, little work having been done on S. haematobium. There is no evidence that resistance to PZQ has been induced in African schistosomes as a result of its large-scale use on that continent to date, but there is also no assurance that PZQ and/or schistosomes are in any way unique and that resistant organisms will not be selected as a result of widespread drug usage. The failure of PZQ to produce complete cures in populations given a routine treatment should therefore solicit considerable concern. With few alternatives to PZQ currently available and/or on the horizon, methods to monitor drug-susceptibility in African schistosomes need to be devised and used to help ensure that this drug remains effective for as long a time as possibl

Praziquantel: its use in control of schistosomiasis in sub-Saharan Africa and current research needs

Treatment with praziquantel (PZQ) has become virtually the sole basis of schistosomiasis control in sub-Saharan Africa and elsewhere, and the drug is reviewed here in the context of the increasing rate that it is being used for this purpose. Attention is drawn to our relative lack of knowledge about the mechanisms of action of PZQ at the molecular level, the need for more work to be done on schistosome isolates that have been collected recently from endemic areas rather than those maintained in laboratory conditions for long periods, and our reliance for experimental work mainly on Schistosoma mansoni, little work having been done on S. haematobium. There is no evidence that resistance to PZQ has been induced in African schistosomes as a result of its large-scale use on that continent to date, but there is also no assurance that PZQ and/or schistosomes are in any way unique and that resistant organisms will not be selected as a result of widespread drug usage. The failure of PZQ to produce complete cures in populations given a routine treatment should therefore solicit considerable concern. With few alternatives to PZQ currently available and/or on the horizon, methods to monitor drug-susceptibility in African schistosomes need to be devised and used to help ensure that this drug remains effective for as long a time as possibl

Neoadjuvant plus adjuvant combined or sequenced vemurafenib, cobimetinib and atezolizumab in patients with high-risk, resectable BRAF-mutated and wild-type melanoma: NEO-TIM, a phase II randomized non-comparative study

Background: Following the increased survival of patients with metastatic melanoma thanks to immunotherapy and targeted therapy, neoadjuvant approaches are being investigated to address the unmet needs of unresponsive and intolerant patients. We aim to investigate the efficacy of neoadjuvant plus adjuvant combined or sequenced vemurafenib, cobimetinib and atezolizumab in patients with high-risk, resectable BRAF-mutated and wild-type melanoma. Methods: The study is a phase II, open-label, randomized non-comparative trial in patients with stage IIIB/C/D surgically resectable, BRAF-mutated and wild-type melanoma, with three possible treatments: (1) vemurafenib 960 mg twice daily from day 1 to 42; (2) vemurafenib 720 mg twice daily from day 1 to 42; (3) cobimetinib 60 mg once daily from day 1 to 21 and from day 29 to 42; and (4) atezolizumab 840 mg for two cycles (day 22 and day 43). Patients will be randomized to three different arms: A) BRAF-mutated patients will receive over 6 weeks (1) + (3); B) BRAF-mutated patients will receive over 6 weeks (2) + (3) + (4); C) BRAF wild-type patients will receive over 6 weeks (3) + (4). All patients will also receive atezolizumab 1200 mg every 3 weeks for 17 cycles after surgery and after a second screening period (up to 6 weeks). Discussion: Neoadjuvant therapy for regional metastases may improve operability and outcomes and facilitate the identification of biomarkers that can guide further lines of treatment. Patients with clinical stage III melanoma may especially benefit from neoadjuvant treatment, as the outcomes of surgery alone are very poor. It is expected that the combination of neoadjuvant and adjuvant treatment may reduce the incidence of relapse and improve survival

Ketorolak-dekstran konjugati: sinteza, in vitro i in vivo vrednovanje

Ketorolac is a non-steroidal anti-inflammatory drug. Dextran conjugates of ketorolac (KD) were synthesized and characterized to improve ketorolac aqueous solubility and reduce gastrointestinal side effects. An N-acylimidazole derivative of ketorolac (KAI) was condensed with a model carrier polymer, dextran of different molecular masses (40000, 60000, 110000 and 200000). IR spectral data confirmed formation of ester bonding. Ketorolac contents were evaluated by UV-spectrophotometric analysis. The molecular mass was determined by measuring viscosity using the Mark-Howink-Sakurada equation. In vitro hydrolysis studies were performed in aqueous buffers (pH 1.2, 7.4, 9) and in 80% (V/V) human plasma (pH 7.4). At pH 9, a higher rate of ketorolac release from KD was observed as compared to aqueous buffer of pH 7.4 and 80% human plasma (pH 7.4), following first-order kinetics. In vivo biological screening in mice and rats indicated that conjugates retained analgesic and anti-inflammatory activities with significantly reduced ulcerogenicity compared to the parent drug.U radu je opisana sinteza konjugata dektrana i protuupalnog lijeka ketorolaka (KD). Konjugati su pripravljeni da bi se povećala topljivost ketorolaka u vodi i smanjila njegova nusdjelovanja u gastrointestinanom traktu. Ketorak je prvo preveden u N-acilimidazolni derivat (KAI) koji je kondenziran s polimernim nosačem, dekstranom različitih molekulskih masa (40000, 60000, 110000 i 200000). IR-spektri potvrdili su nastajanje esterske veze. Udio ketorolaka u konjugatu određen je UV-spektrofotometrijskom analizom. Molekulske mase određene su mjerenjem viskoznosti koristeći Mark-Howink-Sakurada jednadžbu. Hidroliza in vitro praćena je u puferskim otopinama (pH 1,2, 7,4 i 9) i u 80% V/V humanoj plazmi (pH 7,4). Pri pH 9 primjećeno je značajno brže oslobađanje ketorolaka iz KD nego u puferskoj otopini pH 7,4 i krvnoj plazmi. Oslobađanje je prati kinetiku prvog reda. In vivo biološka ispitivanja na miševima i štakorima ukazuju da konjugati imaju analgetsko i protuupalno djelovanje, a značajno smanjeno ulcerogeno djelovanje

Thioredoxin Glutathione Reductase as a Novel Drug Target: Evidence from Schistosoma japonicum

Background: Schistosomiasis remains a major public health concern affecting billions of people around the world. Currently, praziquantel is the only drug of choice for treatment of human schistosomiasis. The emergence of drug resistance to praziquantel in schistosomes makes the development of novel drugs an urgent task. Thioredoxin glutathione reductase (TGR) enzymes in Schistosoma mansoni and some other platyhelminths have been identified as alternative targets. The present study was designed to confirm the existense and the potential value of TGR as a target for development of novel antischistosomal agents in Schistosoma japonicum, a platyhelminth endemic in Asia. Methods and Findings: After cloning the S. japonicum TGR (SjTGR) gene, the recombinant SjTGR selenoprotein was purified and characterized in enzymatic assays as a multifunctional enzyme with thioredoxin reductase (TrxR), glutathione reductase (GR) and glutaredoxin (Grx) activities. Immunological and bioinformatic analyses confirmed that instead of having separate TrxR and GR proteins in mammalian, S. japonicum only encodes TGR, which performs the functions of both enzymes and plays a critical role in maintaining the redox balance in this parasite. These results were in good agreement with previous findings in Schistosoma mansoni and some other platyhelminths. Auranofin, a known inhibitor against TGR, caused fatal toxicity in S. japonicum adult worms in vitro and reduced worm and egg burdens in S. japonicum infected mice. Conclusions: Collectively, our study confirms that a multifunctional enzyme SjTGR selenoprotein, instead of separate Trx

Sinteza i vrednovanje analgetskog, protuupalnog i ulcerogenog djelovanja nekih triazolo- i 2-pirazolil-pirido[2,3-d]-pirimidina

New series of 2-hydrazino-7,8-dihydro-6H-cyclopenta[5,6]pyrido[2,3-d]pyrimidines and its 1,7,8,9-tetrahydrocyclopenta[5,6]pyrido[2,3-d][1,2,4]triazolo[4,3-a]pyrimidine, 1,7,8,-9-tetrahydrocyclopenta[5,6]pyrido[2,3-d][1,2,3,4]tetrazolo[4,5-a]pyrimidine, 8,9-dihydro-7H-cyclopenta[5,6]pyrido[2,3-d]imidazolo[1,2-a]pyrimidine, 2-(pyrazol-1-yl)-7,8-dihydro-6H-cyclopenta[5,6]pyrido[2,3-d]pyrimidine derivatives were prepared in order to obtain new compounds with potential anti-inflammatory and analgesic activity and low ulcerogenic effect. The compounds possessing potent anti-inflammatory activity were further tested for their analgesic and ulcerogenic activities. Compounds 3-amino-6-(4-aryl)-9-(4-arylmethylene)-cyclopenta[5,6]pyrido[2,3-d][1,2,4]triazolo[4,3-a]pyrimidin-5(H)-one (4c), 1-amino-2-methyl-6-(4-aryl)-9-(4-aryl-methylene)-cyclopenta[5,6]pyrido[2,3-d]imidazolo[1,2-a]pyrimidin-5(H)-one (6a), 2-amino-5-(4-aryl)-8-(4-arylmethylene)-cyclopenta[5,6]pyrido[2,3-d]pyrimidine-4(H)-one (9), 2-(3-amino-5-hydroxypyrazol-1-yl)-5-(4-aryl)-8-(4-arylmethylene)-cyclopenta[5,6]-pyrido[2,3-d]pyrimidin-4(H)-one (10a) and 3-thioxo-6-(4-aryl)-9-(4-arylmethylene)-cyclopenta[5,6]pyrido[2,3-d][1,2,4]triazolo[4,3-a]pyrimidin-5(H)-one (13) showed significant analgesic effects. Compound 2-(3-amino-5-hydroxypyrazol-1-yl)-5-(4-aryl)-8-(4-arylmethylene)-cyclopenta[5,6]pyrido[2,3-d]pyrimidin-4(H)-one (10a) was evaluated as the lead compound having higher anti-inflammatory activity (82.8%) than ibuprofen (79.5%) and lower ulcerogenic effect.U radu je opisana sinteza serije 2-hidrazino-7,8-dihidro-6H-ciklopenta[5,6]pirido[2,3-d]pirimidina i njihovih 1,7,8,9-tetrahidrociklopenta[5,6]pirido[2,3-d][1,2,4]triazolo[4,3-a]pirimidinskih, 1,7,8,9-tetrahidrociklopenta[5,6]pirido[2,3-d][1,2,3,4]tetrazolo[4,5-a]pirimidinskih, 8,9-dihidro-7H-ciklopenta[5,6]pirido[2,3-d]imidazolo[1,2-a]pirimidinskih i 2-(pirazol-1-il)-7,8-dihidro-6H-ciklopenta[5,6]pirido[2,3-d]pirimidinskih derivata s potencijalnim protuupalnim i analgetskim te manjim ulcerogenim djelovanjem. Spojevima s izraženim protuupalnim djelovanjem testirano je analgetsko i ulcerogeno djelovanje. Spojevi 3-amino-6-(4-aril)-9-(4-arilmetilen)-ciklopenta[5,6]pirido[2,3-d][1,2,4]triazolo[4,3-a]pirimidin-5(H)-on (4c), 1-amino-2-metil-6-(4-aril)-9-(4-aril-metilen)-ciklopenta[5,6]pirido[2,3-d]imidazolo[1,2-a]pirimidin-5(H)-on (6a), 2-amino-5-(4-aril)-8-(4-arilmetilen)-ciklopenta[5,6]pirido[2,3-d]pirimidin-4(H)-on (9), 2-(3-amino-5-hidroksipirazol-1-il)-5-(4-aril)-8-(4-arilmetilen)- ciklopenta[5,6]-pirido[2,3-d]pirimidin-4(H)-on (10a) i 3-tiokso-6-(4-aril)-9-(4-arilmetilen)-ciklopenta[5,6]pirido[2,3-d][1,2,4]triazolo[4,3-a]pirimidin-5(H)-on (13) pokazali su značajno analgetsko djelovanje. Spoj 2-(3-amino-5-hidroksipirazol-1-il)-5-(4-aril)-8-(4-arilmetilen)-ciklopenta[5,6]pirido[2,3-d]pirimidin-4(H)-on (10a) je vodeći spoj s jačim protuupalnim djelovanjem (82,8%) od ibuprofena (79,5%), a slabijim ulcerogenim djelovanjem

Identification of Thioredoxin Glutathione Reductase Inhibitors That Kill Cestode and Trematode Parasites

Parasitic flatworms are responsible for serious infectious diseases that affect humans as well as livestock animals in vast regions of the world. Yet, the drug armamentarium available for treatment of these infections is limited: praziquantel is the single drug currently available for 200 million people infected with Schistosoma spp. and there is justified concern about emergence of drug resistance. Thioredoxin glutathione reductase (TGR) is an essential core enzyme for redox homeostasis in flatworm parasites. In this work, we searched for flatworm TGR inhibitors testing compounds belonging to various families known to inhibit thioredoxin reductase or TGR and also additional electrophilic compounds. Several furoxans and one thiadiazole potently inhibited TGRs from both classes of parasitic flatworms: cestoda (tapeworms) and trematoda (flukes), while several benzofuroxans and a quinoxaline moderately inhibited TGRs. Remarkably, five active compounds from diverse families possessed a phenylsulfonyl group, strongly suggesting that this moiety is a new pharmacophore. The most active inhibitors were further characterized and displayed slow and nearly irreversible binding to TGR. These compounds efficiently killed Echinococcus granulosus larval worms and Fasciola hepatica newly excysted juveniles in vitro at a 20 µM concentration. Our results support the concept that the redox metabolism of flatworm parasites is precarious and particularly susceptible to destabilization, show that furoxans can be used to target both flukes and tapeworms, and identified phenylsulfonyl as a new drug-hit moiety for both classes of flatworm parasites