Structure-based inhibition of acetylcholinesterase and butyrylcholinesterase with 2-Aryl-6-carboxamide benzoxazole derivatives: synthesis, enzymatic assay, and in silico studies.

An important research topic is the discovery of multifunctional compounds targeting different disease-causing components. This research aimed to design and synthesize a series of 2-aryl-6-carboxamide benzoxazole derivatives that inhibit cholinesterases on both the peripheral anionic and catalytic anionic sides. Compounds (7-48) were prepared from 4-amino-3-hydroxybenzoic acid in three steps. The Ellman test, molecular docking with Maestro, and molecular dynamics simulation studies with Desmond were done (Schrodinger, 12.8.117). Compound 36, the most potent compound among the 42 new compounds synthesized, had an inhibitory concentration of IC50 12.62 nM for AChE and IC50 25.45 nM for BChE (whereas donepezil was 69.3 nM and 63.0 nM, respectively). Additionally, compound 36 had docking values ​​of - 7.29 kcal/mol for AChE and - 6.71 kcal/mol for BChE (whereas donepezil was - 6.49 kcal/mol and - 5.057 kcal/mol, respectively). Furthermore, molecular dynamics simulations revealed that compound 36 is stable in the active gorges of both AChE (average RMSD: 1.98 Å) and BChE (average RMSD: 2.2 Å) (donepezil had average RMSD: 1.65 Å and 2.7 Å, respectively). The results show that compound 36 is a potent, selective, mixed-type dual inhibitor of both acetylcholinesterase and butyrylcholinesterase. It does this by binding to both the catalytically active and peripheral anionic sites of cholinesterases at the same time. These findings show that target compounds may be useful for establishing the structural basis for new anti-Alzheimer agents.

Antifungal Azole Derivatives Featuring Naphthalene Prove Potent and Competitive Cholinesterase Inhibitors with Potential CNS Penetration According to the in Vitro and in Silico Studies.

Cholinesterase inhibition is of great importance in the fight against neurodegenerative disorders such as Alzheimer's disease. Azole antifungals have come under the spotlight with recent discoveries that underline the efficacy and potential of miconazole and its derivatives against cholinesterase enzymes. In this study, we evaluated a library of azoles against acetylcholinesterase and butyrylcholinesterase using in vitro and in silico methods to identify potent inhibitors. Low micromolar IC50 values were obtained for imidazole derivatives, which were further tested and found potent competitive cholinesterase inhibitors via enzyme kinetics study. The active derivatives showed negligible toxicity in in vitro cytotoxicity tests. Molecular modeling studies predicted that these derivatives were druglike, could penetrate blood-brain barrier, and tightly bind to cholinesterase active site making key interactions via the imidazole moiety at protonated state. Thus, current study identifies potent and competitive cholinesterase inhibitor azoles with minor toxicity and potential to pass into the central nervous system.

New chalcone derivatives as effective against SARS-CoV-2 agent.

AIMS: Flavonoids and related compounds, such as quercetin-based antiviral drug Gene-Eden-VIR/Novirin, inhibit the protease of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The alkylated chalcones isolated from Angelica keiskei inhibit SARS-CoV proteases. In this study, we aimed to compare the anti-SARS CoV-2 activities of both newly synthesized chalcone derivatives and these two drugs. METHODS: Determination of the potent antiviral activity of newly synthesized chalcone derivatives against SARS-CoV-2 by calculating the RT-PCR cycling threshold (Ct ) values. RESULTS: Antiviral activities of the compounds varied because of being dose dependent. Compound 6, 7, 9, and 16 were highly effective against SARS-CoV-2 at the concentration of 1.60 µg/mL. Structure-based virtual screening was carried out against the most important druggable SARS-CoV-2 targets, viral RNA-dependent RNA polymerase, to identify putative inhibitors that could facilitate the development of potential anti-coronavirus disease-2019 drug candidates. CONCLUSIONS: Computational analyses identified eight compounds inhibiting each target, with binding affinity scores ranging from -4.370 to -2.748 kcal/mol along with their toxicological, ADME, and drug-like properties.

Investigation of inhibitory effect of sulfated chitosan oligomer on human heparanase enzyme: in silico and in vitro studies.

Deaths from cancer are widespread worldwide and the numbers continue to increase day by day. During the disease progression of cancer in cells, many of its metabolic activities change. Increased heparanase enzyme release is just one example. Following heparanase enzyme activity, many molecules interact with the remodeling of glycosaminoglycan structures, which triggers the release of different enzymes, cytokines, and growth factors, including fibroblast growth factors (FGF1 and FGF2), vascular endothelial growth factor (VEGF), hepatocyte growth factor, transforming growth factor ß and platelet-derived growth factor. These are the most important factors in metastasis due to the formation of new vascular structures caused by those elements. To reduce tumor growth and metastasis, various drugs have been designed by modifying chitosan and its derivatives. In this study, we used chitosan oligomer (A), sulfated chitosan oligomer (ShCsO) (B), heparin (C), phosphate monomer (D1) of PI-88 and sulfate monomer (D2) of PI-88 as heparanase inhibitors. We modified the chitosan oligomer with chlorosulfonic acid to synthesize ShCsO to investigate its inhibitory effects on human serum heparanase. Also examined were molecular docking; molecular dynamics (MD); adsorption, distribution, metabolism, elimination and toxicity (ADMET); and target prediction. ShCsO decreased enzyme activity at a concentration of 0.0001 mg/mL. The docking scores of A, B and C from in silico studies were -6.254, -6.936 and -6.980 kcal/mol, respectively, and the scores for the two different PI-88 monomers were -5.741 and -5.824 kcal/mol. These results show that ShCsO may be a potential drug candidate for treating cancer.Communicated by Ramaswamy H. Sarma.

Exploring enzyme inhibition profiles of novel halogenated chalcone derivatives on some metabolic enzymes: Synthesis, characterization and molecular modeling studies.

Enzyme inhibition is a very active area of research in drug design and development. Chalcone derivatives have a broad enzyme inhibitory activity and function as potential molecules in the development of new drugs. In this study, the synthesized novel halogenated chalcones with bromobenzyl and methoxyphenyl moieties were evaluated toward the acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes and human erythrocyte carbonic anhydrase I (hCA I), and II (hCA II) isoenzymes. They showed highly potent inhibition ability toward AChE with Ki values of 1.83 ± 0.21-11.19 ± 0.96 nM and BChE with Ki values of 3.35 ± 0.91-26.70 ± 4.26 nM; hCA I with Ki values of 29.41 ± 3.14-57.63 ± 4.95 nM, and hCA II with Ki values of 24.00 ± 5.39-54.74 ± 1.65 nM. Among the tested enzyme inhibitions, compounds 14 and 13 were the most active compounds against AChE and BChE. Docking studies were performed to the most active compounds against AChE, BChE, hCA I and hCA II to propose a binding mode in the active site and molecular dynamics simulations were studied to check the molecular interactions and the stability of the ligands in the active site. The results may contribute to the development of new drugs particularly to treat some global disorders including Alzheimer's disease (AD), glaucoma, and diabetes.

Azoles containing naphthalene with activity against Gram-positive bacteria: in vitro studies and in silico predictions for flavohemoglobin inhibition.

Azoles are first-line drugs used in fungal infections. Topical antifungals, such as miconazole and econazole, are known to be active against Gram-positive bacteria, which was reported to result from bacterial flavohemoglobin (flavoHb) inhibition. Dual antibacterial/antifungal action is believed to have benefits for antimicrobial chemotherapy. In this study, we tested antibacterial effects of an in-house library of naphthalene-bearing azoles, some of which were reported as potent antifungals, in an attempt to find dual-acting hits. Several potent derivatives were obtained against the Gram-positive bacteria, Enterococcus faecalis and Staphylococcus aureus. 9 was active at a minimum inhibitor concentration (MIC) less than 1 µg/ml against E. faecalis and S. aureus, and 10 against S. aureus. 16 was also potent against E. faecalis and S. aureus (MIC = 1 and 2 µg/ml, respectively). Six more were active against S. aureus with MIC ≤ 4 µg/ml. In vitro cytotoxicity studies showed that the active compounds were safe for healthy cells within their MIC ranges. According to the calculated descriptors, the library was found within the drug-like chemical space and free of pan-assay interference compounds (PAINS). Molecular docking studies suggested that the compounds might be bacterial flavohemoglobin (flavoHb) inhibitors and the azole and naphthalene rings were important pharmacophores, which was further supported by pharmacophore modeling study. As a result, the current study presents several non-toxic azole derivatives with antibacterial effects. In addition to their previously reported antifungal properties, they could set a promising starting point for the future design of dual acting antimicrobials. Communicated by Ramaswamy H. Sarma.

Preoperative color Doppler assessment in planning of gluteal perforator flaps.

Gluteal artery perforator flaps have gained popularity due to reliability, preservation of the muscle, versatility in flap design without restricting other flap options, and low donor-site morbidity in ambulatory patients and possibility of enabling future reconstruction in paraplegic patients. But the inconstant anatomy of the vascular plexus around the gluteal muscle makes it hard to predict how many perforators are present, what their volume of blood flow and size are, where they exit the overlying fascia, and what their course through the muscle will be. Without any prior investigations, the reconstructive surgeon could be surprised intraoperatively by previous surgical damage, scar formation, or anatomic variants.For these reasons, to confirm the presence and the location of gluteal perforators preoperatively we have used color Doppler ultrasonography. With the help of the color Doppler ultrasonography 26 patients, 21 men and 5 women, were operated between the years 2002 and 2007. The mean age of patients was 47.7 (age range: 7-77 years). All perforator vessels were marked preoperatively around the defect locations. The perforator based flap that will allow primary closure of the donor site and the defect without tension was planned choosing the perforator that showed the largest flow in color Doppler ultrasonography proximally. Perforators were found in the sites identified with color Doppler ultrasonography in all other flaps. In our study, 94.4% flap viability was ensured in 36 perforator-based gluteal area flaps. Mean flap elevation time was 31.9 minutes. We found that locating the perforators preoperatively helps to shorten the operation time without compromising a reliable viability of the perforator flaps, thus enabling the surgeon easier treatment of pressure sores.

Evaluation of serum ischaemia-modified albumin levels in patients with Bell's palsy.

OBJECTIVE: This prospective study aimed to evaluate the relationship between serum ischaemia-modified albumin levels and Bell's palsy severity. METHODS: The study included 30 patients diagnosed with Bell's palsy and 30 healthy individuals. The patients were separated into three disease severity groups (grades 2, 3 and 4) according to House-Brackmann classification. Blood samples were collected from all participants and the results compared between groups. RESULTS: Significant differences in serum ischaemia-modified albumin were found between the study and control groups (p < 0.001); values were significantly higher in the study group than in the control group. CONCLUSION: The significantly higher levels of serum ischaemia-modified albumin in the study group suggest that Bell's palsy pathogenesis is associated with oxidative stress.

Loss of wild-type p53 and C-erbb2 amplification correlates with high-grade breast carcinomas.

Breast cancer is the most common cancer in women in the western world. Two of the most frequently occuring chromosomal abnormalities in human breast carcinoma are the loss of p53 tumour suppressor gene function and the amplification of the c-erbB2 oncogene. Previous studies have demonstrated the role of p53 gene product in the maintenance of chromosomal stability and the correlation between c-erbB2 amplification and breast carcinogenesis. In this study we have examined the existence of a possible correlation between these genetic alterations in a panel of 83 malignant breast tumours (69 adeno and 14 lobular carcinomas). The status of a related gene, c-erbB3, was also examined. With the aid of microsattelite marker TP53CA loss of heterozygosity (LOH) was detected in the p53 locus in 49% of the tumours. Histochemical analysis of 64 of these tumours with the p53 antibody CM1 demonstrated staining, indicative of an elevated steady-state level of p53 protein in 23 rumours (36%). Amplification of the c-erbB2 gene was detected in 20 of 75 tumours analysed (27%). In the tumours with c-erbB2 amplification 12 also had p53 LOH. In at least another 2 tumours there was increased p53 protein level but no LOH. Therefore in 75% of the tumours with c-erbB2 amplification there was evidence of loss of normal p53 function. There was no evidence of c-erbB3 amplification in any of the 75 rumours analysed. The data presented demonstrates a strong correlation between the loss of p53 and tumour grade (p<0.00545), and a strong association between c-erbB2, but not c-erbB3, amplification and loss of p53 (p<0.0170).

DNA repair and resistance to topoisomerase I inhibitors: mechanisms, biomarkers and therapeutic targets.

Irinotecan and topotecan are derivatives of the naturally occurring cytotoxic compound camptothecin that are used in the treatment of patients with colorectal cancer, either as single agents or in combination with radiotherapy and/or other chemotherapy drugs. They are inhibitors of DNA topoisomerase I (Top I) and exert their cytotoxic effects in replicating cells by inducing DNA strand breaks. A wide range of DNA repair proteins is involved in the recognition and repair of these breaks, and depletion or inhibition of some of these proteins increases the cytotoxic effects of Top I inhibitors. Building on these laboratory observations, ongoing translational research is aiming to establish whether this mechanistic information can be used to improve the treatment of patients with certain types of cancer. Two potential strategies are under investigation: (1) individualising treatment by evaluating levels and/or patterns of expression of DNA repair proteins that predict clinical response to Top I inhibitors, and (2) developing small molecule inhibitors of these repair enzymes to overcome tumour resistance and improve outcomes. This review summarises the current status of these research endeavours, focusing on the key roles of tyrosyl DNA phosphodiesterase 1 (Tdp1) and poly(ADP-ribose) polymerase (PARP), and examines the pre-clinical and clinical data that support the potential value of these and other DNA repair proteins as predictive markers and therapeutic targets. Since irinotecan is increasingly being combined with radiotherapy, the potential for these proteins to act as predictive biomarkers for both Top I inhibitors and radiation is proposed, and the possibility of synergistic potentiation of chemoradiation regimes by Tdp1 and/or PARP inhibitors is considered.

Staged and late-period reconstruction of the crushed hand: prefabricated osseous flap.

The principle of controlled utilization of increased vascularity in the regions of artificially established ischemia constituted the basis of prefabrication of the vascular induction through staged transfers. We have used this principle, and a part of a metacarpal bone was prefabricated with an artery. The artery was inserted into the bone, and a defect was repaired with this prefabricated osseous flap; meanwhile, another defect was amended with a bone graft. The static bone scintigraphy of the hand at the 6-month postoperative stage indicated evident superiority of the vascularity of the prefabricated osseous flap at the ring finger when compared with the bone graft at the middle finger. The angiography demonstrated a high vascular pattern of the flap at its location at the proximal phalanx of the ring finger. The structures that remained healthy after the injury either on the amputated side or on the hand could be used in reconstruction. The tendinous and osseous structures could be used as free grafts, and the vascular structures could be transferred as vascular pedicles, allowing the creation of previously nonexistent flaps and composite tissues that were ideal for reconstruction. Any tissue possessing a vascular supply could be used as a vascular crane in any prefabrication process.

A congenital true teratoma with cleft lip, palate, and columellar sinus.

Teratomas, the most common extragonadal germ cell tumor of childhood, involve at least two of the ectodermal, mesodermal, and endodermal layers. Of the teratomas seen in the first 2 months of life, 82% are sacrococcygeal. The head and neck region is the second most common location for teratomas in early infancy, accounting for five (14%) of those cases. We describe a female neonate with a teratoma of the nasopharyngeal area, bilateral cleft palate/lip, and columellar sinus pathologies. The mass, which was 8 x 5 x 7 cm and soft in consistency, blocked the airway and prevented oral feeding. On macroscopic examination of the excised mass, there was a notable typical cilia arrangement and lower eyelid appearance. The patient, who was diagnosed with a well-differentiated teratoma after the pathologic examination, did not have any complications in the postoperative period.

A new method in the treatment of ear amputation: experimental and clinical study.

There have been plenty of reconstruction methods for ear amputation, and replantation preserves its importance. In situations where replantation is not feasible, various methods were proposed. We indicate an alternative technique for the ear amputation without replantation indication. The method of replacing of a vascular structure into the tunnel formed on the posterior side of the amputated ear was used instead of replacing the ear cartilage into a vascular area that was described in the literature of ear prefabrication. The dorsal fascial flaps which were prepared from the back of 10 New Zealand rabbits were placed into the amputated ear. The 2 groups, control and the experimental, were consequently the ear that was adapted as a composite graft and the ear with the flap inserted. The ears were examined macroscopically and photographed on postoperative days 3, 7, 14, and 21. On the 21st day, the nourishment pattern of the ear, the dorsal fascia, and the dorsal fascia adapted ear were investigated with digital subtraction angiography (DSA). The group that received applied dorsal fascia possessed increased vascularity. The viability was evaluated with the biopsies taken from the control group and the group that received applied dorsal fascial flap on the 21st day. The cartilage and the connective tissue were viable in the flap-applied group, whereas there was necrosis in the control group. The reflection of the experimental study was performed on 2 subtotal and 1 total ear amputation cases, with the utilization of the superficial temporal artery. The nourishment of the flaps was evaluated with postoperative photographs, angiography, and bone scintigraphy.

Reverse homodigital artery flap coverage for bone and nailbed grafts in fingertip amputations.

The main aim of the treatment of fingertip amputations with no indication of replantation was to establish the functional and esthetic construction. The critical point in the utilization of the bone and nail tissue as a graft for reconstruction was to choose a flap that is sufficiently vascular to nourish these grafts. We have performed homodigital artery flaps to cover the bone and nailbed grafts taken from the amputation to restore fingertip function with an acceptable result. The venous insufficiency with the increased probability in flap failure should be taken into consideration. We proposed the preservation of some amount of soft tissue around the vascular pedicle to overcome the venous insufficiency and in our point of view, digital artery sacrifice was worth it to preserve the length of the finger and the esthetic nail appearance.

An alternative dressing material for the split-thickness skin graft donor site: oxidized regenerated cellulose.

The split-thickness skin graft (STSG) donor sites have been treated with various and plenty of dressing techniques and materials. An ideal STSG donor site dressing should have antibacterial, hemostatic, and promoting epidermal healing properties. We have performed a prospective study to evaluate the effect of the oxidized regenerated cellulose on STSG donor site healing. Between January 2002 and January 2005, 40 patients who were operated in any kind of reconstructive operations with STSG donor sites were included in the study. One half of the wound was covered with oxidized regenerated cellulose and the other half of the same wound of the same patient was covered with fine mesh gauze treated with Furacin (nitrofurazone). The patients were grouped into 2 depending on the dressing technique: group I, semiclosed and group II, closed. The wounds were evaluated for healing time, infection, pain perception of the patient, and final esthetic results. The oxidized regenerated cellulose side of the group I was healed in a mean of 6.5 +/- 0.51 days; in group II, 5.4 +/- 0.50 days (range, 5-6 days). The fine mesh gauze treated with Furacin in group I was healed in a mean of 9.9 +/- 0.97 days (range, 8-11 days); in group II, 8.4 +/- 0.99 days (range, 7-10 days). There was a statistical significance between the oxidized regenerated cellulose side and the fine mesh gauze side (P < 0.001) in group I and group II separately. The difference between group I and group II was statistically significant in the oxidized regenerated cellulose side (P < 0.001), and the difference between group I and group II was statistically significant in the fine mesh gauze side (P < 0.005). The antibacterial, hemostatic, and absorbable property of the oxidized regenerated cellulose could ensure the utilization as an alternative STSG donor site dressing, especially because the positive influence over the wound healing was proven.

Effects of indoleamines on sperm motility in vitro.

Indoleamines are products of the pineal gland and are postulated to play an antigonadotrophic role in the reproductive system of mammals. In humans, indoleamines have been localized in tissue fluids such as plasma, serum and cerebrospinal fluid. Because indoleamines exhibit antigonadotrophic properties, the authors examined whether these agents cause inhibitory effects on sperm motility. In this study, time and dose-dependent inhibition of sperm motility by indoleamines was observed. Furthermore, the presence of indoles in incubation medium decreased sperm velocity. These data suggest that the presence of high doses of indoles in reproductive fluids may inhibit sperm motility and velocity.