Fragment Merging, Growing, and Linking Identify New Trypanothione Reductase Inhibitors for Leishmaniasis.

Trypanothione reductase (TR) is a suitable target for drug discovery approaches against leishmaniasis, although the identification of potent inhibitors is still challenging. Herein, we harnessed a fragment-based drug discovery (FBDD) strategy to develop new TR inhibitors. Previous crystallographic screening identified fragments 1-3, which provided ideal starting points for a medicinal chemistry campaign. In silico investigations revealed critical hotspots in the TR binding site, guiding our structure- and ligand-based structure-actvity relationship (SAR) exploration that yielded fragment-derived compounds 4-14. A trend of improvement in Leishmania infantum TR inhibition was detected along the optimization and confirmed by the crystal structures of 9, 10, and 14 in complex with Trypanosoma brucei TR. Compound 10 showed the best TR inhibitory profile (Ki = 0.2 µM), whereas 9 was the best one in terms of in vitro and ex vivo activity. Although further fine-tuning is needed to improve selectivity, we demonstrated the potentiality of FBDD on a classic but difficult target for leishmaniasis.

Optimization of Potent and Specific Trypanothione Reductase Inhibitors: A Structure-Based Drug Discovery Approach.

Leishmania spp. are responsible for up to 1 million new cases each year. The current therapeutic arsenal against Leishmania is largely inadequate, and there is an urgent need for better drugs. Trypanothione reductase (TR) represents a druggable target since it is essential for the parasite and not shared by the human host. Here, we report the optimization of a novel class of potent and selective LiTR inhibitors realized through a concerted effort involving X-ray crystallography, synthesis, structure-activity relationship (SAR) investigation, molecular modeling, and in vitro phenotypic assays. 5-Nitrothiophene-2-carboxamides 3, 6e, and 8 were among the most potent and selective TR inhibitors identified in this study. 6e and 8 displayed leishmanicidal activity in the low micromolar range coupled to SI > 50. Our studies could pave the way for the use of TR inhibitors not only against leishmaniasis but also against other trypanosomatidae due to the structural similarity of TR enzymes.

Abductor muscle strengthening in THA patients operated with minimally-invasive anterolateral approach for developmental hip dysplasia.

OBJECTIVE: In developmental hip dysplasia (DDH) patients, the chronic dislocation of the femoral head with respect to the true acetabulum determines muscle contracture and atrophy, particularly of the abductor muscles, and leads to secondary osteoarthritis (OA) with severe motor dysfunction, pain and disability. The correct positioning when a total hip replacement (THR) is performed is fundamental to the recovery of gait function. Also, inadequate rehabilitation of the abductor muscles for pelvic stabilisation can be responsible for residual dysfunction. Consensus on a programme for abductor muscle strengthening in these patients is not currently available. The aim of this study was to evaluate the effectiveness of a specific program of exercises for strengthening the abductor muscles in these patients. METHODS: A multicentre, prospective, randomised clinical trial was carried out in an outpatient rehabilitation setting on 103 patients given THR for DDH through a minimally-invasive anterolateral approach. Patients were randomly divided into a Study Group, including 46 patients, and a Control Group, including 57 patients. All patients underwent standard early postoperative rehabilitation. In addition, the Study Group were given an extra 2-week rehabilitation once full weight-bearing on the operated limb was allowed, aimed at strengthening the abductor muscles. All patients were evaluated preoperatively, and at about 3 and 6 months postoperatively. Clinical measures (lower limb-length differences, hip range of motion, abductor muscle strength), and functional measures (WOMAC, HHS, 10mt WT, SF-12) were taken. RESULTS: Hip range of motion and functional outcome measures showed a progressive improvement at follow ups in both groups, significantly higher in the Study Group. In particular, abductor strength at 6 months post-op improved by 92.5% with respect to 35.7% in the Control Group. CONCLUSION: In addition to standard rehabilitation, a rehabilitation programme for strengthening the gluteal muscles in DDH patients who underwent THR determined an increase in muscle strength that improved functional performance and patient satisfaction.

Leaf Decoction of Carica papaya Combined with Artesunate Prevents Recrudescence in Plasmodium berghei-Infected Mice.

Malaria treatment and control have become increasingly difficult because of the spread of drug-resistant strains of Plasmodium falciparum and Plasmodium vivax. Thus, there is a continuous need to develop new combination therapies such as artemisinin-based combination therapies (ACTs) to contrast the emergence of resistant Plasmodium strains. Despite ACT has been recommended by the World Health Organization since 2001, its overall deployment in poor endemic areas is very slow, principally due to its high cost. In the malaria endemic areas, plant remedies are still widely used mostly without assurance of their efficacy and/or safety. A variety of widespread herbal drugs or natural products were already reported for their possible plasmodicidal activities, but the studies concerning their activity in combination with artemisinins are very scarce. The antimalarial activity of papaya is mostly anecdotal, and the present study is aimed at investigating the antiplasmodial activity of a decoction obtained by traditional recipe from the mature leaves of Carica papaya. The decoction was analyzed by HPLC-DAD-MS (high performance liquid chromatography coupled with diodoarray detector and mass spectrometry) showing the presence of caffeoyl derivatives and di- and triglycosides of flavonols. The extract was found to be active against P. falciparum 3D7 strains with a synergism in the presence of artemisinin. In vivo activity against the murine malaria model of Plasmodium berghei was disclosed both for the dried extract alone (250, 500, and 750 mg/kg/d) and for its combination with artesunate (250 mg/kg/d papaya plus 10 mg/kg/d artesunate). This combination displayed the greatest antimalarial activity in terms of reduction of parasitemia and prevention of recrudescence in animals recovered from the infection.

Novel Aminoquinoline Derivatives Significantly Reduce Parasite Load in Leishmania infantum Infected Mice.

In this Letter, a detailed analysis of 30 4-aminoquinoline-based compounds with regard to their potential as antileishmanial drugs has been carried out. Ten compounds demonstrated IC50 < 1 µM against promastigote stages of L. infantum and L. tropica, and five compounds showed IC50 < 1 µM against intramacrophage L. infantum amastigotes. Two compounds showed dose-dependent enhancement of NO and ROS production by bone marrow-derived macrophages and remarkable reduction of parasite load in vivo, with advantage of being short-term and orally active. To the best of our knowledge, this is the first example of 4-amino-7-chloroquinoline derivatives active in Leishmania infantum infected mice.

The use of braces in the rehabilitation treatment of the post-traumatic elbow.

The elbow, the middle joint of the upper limb, enables the hand to be placed at various distances from the body. The articular, muscular and neuromotor complexity of the elbow is such that it is often prone to stiffness, especially if immobilized for long periods of time. Therefore, mobilization of the posttraumatic elbow must be started early. In the presence of lesions to the ligamentous structures, the joint must be protected to prevent these structures from being placed under tension during movement. Rehabilitation of the elbow includes the use of braces. Different types of brace are used depending on clinical situation and the objectives to be achieved. They can have fixed protection or locked articulation, allow an adjustable range of movement to restrict flexion-extension and pronation-supination, or allow dynamic and static progressive movement. The latter plays a special role in conservative treatment and following surgical release. However, the effectiveness of braces in the rehabilitation treatment of elbow stiffness depends on the patient's compliance. Their use requires a considerable amount of physician time to achieve the objectives envisaged by the rehabilitation program.

Functional results in calcific tendinitis of the shoulder treated with rehabilitation after ultrasonic-guided approach.

Calcific tendinopathy of the rotator cuff is a chronic disease that mostly in the acute phase compromises the articular function. The aim of this study is to estimate the effectiveness of the ultrasonic-guided percutaneous treatment (UGPT) in association with the rehabilitative treatment. We evaluated 106 patients with calcific tendinopathy, treated by UGPT. They underwent clinical evaluation by a physiatrist at T0 (the same day of UGPT), and were reassessed at follow-up 1 month (T1) after treatment. The assessment at T0 and T1 was done by the Constant-Murley scale. Analyzing the results, we found that at T0, the average Constant score was 43.5 out of 100; at T1 it was 83.2 out of 100. The improvement was statistically significant (P < 0.0005). We found that UGPT and rehabilitation associated with the multidisciplinary management of the patient (orthopedic surgeon-radiologist-physiatrist) was able to prevent adhesive bursitis, and to achieve clinical cure in most of the treated cases.

Inhibitory Effect of Silver Nanoparticles on Trypanothione Reductase Activity and Leishmania infantum Proliferation.

In Leishmania the glutathione/glutathione reductase eukaryotic redox sys-tem is replaced by the unique trypanothione/trypanothione reductase (TR) system. In vitro, silver is a more effective TR inhibitor than antimony, the first line drug against leishmaniasis in most endemic countries, and its mechanism of inhibition is similar to that of Sb(III). In particular, silver binds with high affinity to the catalytic triad Cys52, Cys57, and His461', thereby inhibiting TR. Here, Ag(0) activity was tested on the promastigote and amastigote stages of Leishmania infantum using a drug-delivery system consisting in Ag(0) nanoparticles encapsulated by ferritin molecules (PfFt-AgNPs). These were able to induce an antiproliferative effect on the parasites at metal concentrations lower than those used with antimony.

Treatment of scapula dyskinesia with botulin toxin: two case reports.

We report two cases of scapula-thoracic dyskinesia with different etiologies where both patients complained of functional limitation and pain in the shoulder. The first case was caused by a road accident, the second by sequelae of surgery to remove aggressive scapula-axillary fibromatosis. In both patients, therapy with botulin toxin type A (Botox) was performed, which determined a reduction in pain. In the first case, there was also an improvement in function. There were no side effects in the two patients after the injections.