A Study on Millimeter Wave SAR Imaging for Non-Destructive Testing of Rebar in Reinforced Concrete.

In this study, we investigate a millimeter wave (mmWave) synthetic aperture radar (SAR) imaging scheme utilizing a low-cost frequency modulated continuous wave (FMCW) radar to take part in non-destructive testing which could be a useful tool for both civilian and military demands. The FMCW radar working in the frequency range from 76 GHz to 81 GHz is equipped with a 2-D moving platform aiming to reconstruct the 2-D image of the shape of the target object. Due to the lab environment containing several devices and furniture, various noise and interference signals from the floor are not avoidable. Therefore, the digital signal processing algorithms are joined to remove the undesired signals as well as improve the target recognition. This study adopts the range migration algorithms (RMAs) on the processed reflected signal data to form the image of the target because of its verified ability in this type of mission. On the other hand, the integration of compressed sensing (CS) algorithms into the SAR imaging system is also researched which helps to improve the performance of the system by reducing the measurement duration while still maintaining the image quality. Three minimization algorithms are used involving the imaging system as the CS solvers reconstruct the radar data before being processed by RMA to form the image. The proposed imaging scheme demonstrates its good ability with high azimuth resolution in the mission of detecting tiny cracks in the rebar of reinforced concrete. In addition, the participation of CS algorithms improves the performance of the scheme as the cracks on the rebar can be located on the images, which are reconstructed from only 30% of the dataset. The comparison of CS solvers shows that ADMM outperforms the other candidates in the reconstruction task.

Phenoxypropanolamine derivatives as selective inhibitors of the 20S proteasome ß1 and ß5 subunits.

New series of thiophene-containing phenoxypropanolamines were synthesized and evaluated for their potency to inhibit the three proteolytic activities of the mammalian 20S proteasome. Noticeable inhibition of both ChT-L and PA activities was obtained with three compounds: one with unsubstituted phenoxypropanolamine group (7) and the two others with a p-Cl-substituted group (4 and 9). For three other compounds (3, 8 and 10), ChT-L activity alone was significantly inhibited. In silico docking performed on the ß5 and ß1 subunits bearing the respective ChT-L and PA catalytic sites showed features common to poses associated with active compounds. These features may constitute a selectivity criterion for structure-guided inhibitor design.

Acute Patellar Tendon Rupture after Total Knee Arthroplasty Revision.

Patellar tendon rupture is a catastrophic complication following total knee arthroplasty (TKA). Though revision TKA has been suspected of being a predisposing factor for the occurrence of patellar tendon rupture, there are few reports on patellar tendon rupture after revision TKA. Here, we present a case of acute patellar tendon rupture that occurred after TKA revision. In the patient, the patellar tendon was so thin and could not be repaired, and accordingly was sutured end to end. We used the anterior tibialis tendon allograft to augment the poor quality patellar tendon tissue. Fixation of the allograft was done by using the bone tunnel created through tibial tuberosity and suturing the allograft to the patellar tendon and quadriceps tendon. The patient was instructed to wear a full extension knee splint and was kept non-weight bearing for 6 weeks after operation. Full knee extension could be achieved 6 weeks postoperatively.

Bisbenzimidazole derivatives as potent inhibitors of the trypsin-like sites of the immunoproteasome core particle.

In this study, a monomeric (MB) and a dimeric (DB) bisbenzimidazoles were identified as novel proteasome inhibitors of the trypsin-like activity located on ß2c sites of the constitutive 20S proteasome (IC50 values at 2-4 µM range). Remarkably, they were further shown to be 100- and 200-fold more potent inhibitors of the immunoproteasome trypsin-like activity (ß2i sites, IC50=24 nM) than of the homologous constitutive activity. Molecular models of inhibitor/enzyme complexes in the two types of trypsin-like sites and corresponding computed binding energy values corroborated kinetic data. Different binding modes were suggested for MB and DB to the ß2c and ß2i trypsic sites. Each pointed to better contacts of the ligand inside the ß2i active site than for ß2c site. MB and DB represent the first selective inhibitors of the immunoproteasome trypsin-like activity described to date and can be considered as prototypes for inhibiting this activity.

New C(4)- and C(1)-derivatives of furo[3,4-c]pyridine-3-ones and related compounds: evidence for site-specific inhibition of the constitutive proteasome and its immunoisoform.

A set of 18 new C(4) and C(1) derivatives of nor-cerpegin (1,1-dimethyl furo[3,4-c]pyridine-3-one), 6 model compounds (γ- and δ-lactones) and 20 furo- or thieno[2,3-d]-pyrimidine-4-one related compounds were designed and synthesized. Each compound was assayed for inhibition of CT-L, T-L and PA proteolytic activities of 20S constitutive proteasome (c20S). Most performant compounds were also assayed on 20S immunoproteasome (i20S). Compound 10 with a benzylamino group at C(4) and dimethylated at C(1) of the furopyridine ring was the most efficient PA site-specific inhibitor of the c20S (IC50(cPA) of 600nM) without noticeable inhibition of the i20S PA site (iPA). In silico docking assays for 10 at the iPA catalytic site revealed the absence of poses normally observed for this compound and related ones at the constitutive PA site (cPA). The thieno[2,3-d]pyrimidine-4-one 40 was T-L site-specific with a mild inhibition of both c20S and i20S in vitro (IC50(cT-L) of 9.9µM and IC50(iT-L) of 6.7µM). In silico docking assays of 40 at T-L sites of c20S and i20S revealed almost identical first rank poses in the two types of sites with no possibility left for nucleophilic attack by Thr1 as observed for the fused furopyridine-3-one 10.

C1 and N5 derivatives of cerpegin: synthesis of a new series based on structure-activity relationships to optimize their inhibitory effect on 20S proteasome.

Thirty-two new derivatives of cerpegin (1,1,5-trimethylfuro[3,4-c]pyridine-3,4-dione) were designed and synthesized in high yield by a new method, combining several C(1) and N(5) substituents. All compounds were tested for their inhibitory effect on the CT-L, T-L and PA proteolytic activities of a purified mammalian 20S proteasome. Only one molecule inhibited both CT-L and PA activities. Sixteen molecules specifically inhibited PA at the micromolar range, out of which fourteen had IC50 values around 5 µM and two had IC50 values closer to 2 µM. Except in one case, neither calpain I nor cathepsin B was inhibited. In silico docking suggests a unique mode of binding of the most efficient compounds to the ß1 catalytic site (PA activity) in relation to the chemical nature of C(1) substituents.

A new series of N5 derivatives of the 1,1,5-trimethyl furo[3,4-c]pyridine-3,4-dione (cerpegin) selectively inhibits the post-acid activity of mammalian 20S proteasomes.

A large set of N(5)-derivatives of cerpegin (1,1,5-trimethyl furo[3,4-c]pyridine-3,4-dione) was designed and synthesized in high yields by a simple and handy method using various primary amines for a pyridine cycle synthesis. The effects of 29 derivatives on the three types of catalytic sites of purified mammalian 20S proteasomes (CT-L, T-L and PA) were measured. Most of the new compounds specifically inhibited the PA activity, in the micromolar range. Docking experiments support these results. Moreover, neither calpain I nor cathepsin B were inhibited.