Understanding the helical stability of charged peptides.

Cationic helical peptides play a crucial role in applications such as anti-microbial and anticancer activity. The activity of these peptides directly correlates with their helicity. In this study, we have performed extensive all-atom molecular dynamics simulations of 25 Lysine-Leucine co-polypeptide sequences of varying charge density ( λ ) and patterns. Our findings showed that, an increase in the charge density on the peptide leads to a gradual decrease in the helicity up to a critical charge density λ c . Beyond λ c , a complete helix to coil transition was observed. The decrease in the helicity is correlated with the increased number of water molecules in first solvation shell, solvent-exposed surface area, and a higher value of the radius of gyration of the peptide.

Laparoscopic excision of a schwannoma arising in the psoas muscle.

Schwannoma occurring in the psoas muscle is rare. We report a 49-year-old male who presented to the orthopaedic oncosurgery team with persistent lower back pain radiating to the right lower limb following a fall on the back a few months ago. Magnetic resonance imaging revealed a well-defined lesion in the right psoas muscle at the level of third lumbar vertebra (L3). He underwent a laparoscopic excision of this mass using one 10 mm and two 5 mm ports. Intraoperative frozen section after a complete excision showed this to be a benign schwannoma. He was discharged the day after surgery. His symptoms gradually reduced over a period of time and he remains well 3 years after surgery. This case highlights the feasibility and safety of minimally invasive treatment of this rare tumour.

Does a Modified Technique to Achieve Arthrodesis of the Wrist After Resection of the Distal Radius and Translocating the Ipsilateral Ulna as a Vascularized Graft to Reconstruct the Defect Improve Grip Strength and Outcomes Scores?

BACKGROUND: Ten years ago, we reported the results of a procedure in which we translocated the ipsilateral ulna as a vascularized autograft to reconstruct defects of the distal radius after tumor resection, with excellent functional results. At that time, wrist arthrodesis was achieved by aligning the translocated ulna with the scapholunate area of the carpus and usually the third metacarpal. This resulted in wrist narrowing. We then wondered if aligning the translocated ulna with the scaphoid and the second metacarpal would result in ulnar deviation and thereby improve grip strength. We believed lateralization would reduce the wrist narrowing that occurs with fusion to the third metacarpal and would make the cosmesis more acceptable. We also modified the incision to dororadial to make the scar less visible and thus improve the cosmesis. QUESTIONS/PURPOSES: (1) Is there an objective improvement in grip strength and functional scores (Musculoskeletal Tumor Society [MSTS] and Mayo wrist) when the translocated ulna is lateralized and the wrist is fused with the translocated ulna and aligned with the second metacarpal versus when the translocated ulna is aligned with the third metacarpal? (2) Did lateralization caused by the wrist fusion aligned with the second metacarpal minimize wrist narrowing as measured by the circumference compared with the fusion aligned with the third metacarpal? METHODS: From 2010 and 2018, we treated 40 patients with distal radius tumors at our institution, 30 of whom had a distal radius enbloc resection. Twenty-eight patients had an ipsilateral ulna translocation and wrist arthrodesis in which the radius and translocated ulna were aligned with either the second (n = 15) or the third (n = 13) metacarpals. Two patients in the second metacarpal group and three patients in the third metacarpal group were lost to follow-up before 24 months after surgery and were excluded. A retrospective analysis of 23 patients (20 with giant cell tumors and three with malignant bone tumors) included a review of radiographs and institutional tumor database for surgical and follow-up records to study oncologic (local disease recurrence), reconstruction (union of osteotomy junctions, implant breakage or graft fracture, and wrist circumference), and functional outcomes (MSTS and Mayo wrist scores and objective grip strength assessment compared with the contralateral side). The results were compared for each study group (second metacarpal versus third metacarpal). There was no difference in the incidence of local recurrence or the time to union between the two groups. There were no implant breakages or graft fractures noted in either group. RESULTS: Patients in the second metacarpal group lost less grip strength compared with the unoperated side in the third metacarpal group (median 12% [range -30% to 35%] versus median 28% [15% to 42%], difference of medians 16%; p = 0.006). There were no between-group differences in terms of MSTS (median 30 [24 to 30] versus median 26.5 [22 to 30], difference of medians 3.5; p = 0.21) or Mayo wrist scores (median 83 [65 to 100] versus median 72 [50 to 90], difference of medians 11; p = 0.10). The second metacarpal group also had less wrist narrowing as seen from the median difference in circumference between the operated and unoperated wrists (median narrowing 10 mm [3 to 35 mm] in the second metacarpal group versus median 30 mm [15 to 35 mm] in the third metacarpal group, difference of medians 20 mm; p = 0.04). CONCLUSION: Wrist arthrodesis after ulna translocation with alignment of the translocated ulna and the second metacarpal provides a functional position with ulnar deviation that offers some improvement in grip strength but no improvement in the MSTS or Mayo scores. Radialization/lateralization of the translocated ulna achieved from the alignment with the second metacarpal decreases the reduction in the wrist circumference and therefore reduces wrist narrowing. LEVEL OF EVIDENCE: Level III, therapeutic study.

Evaluation of the Efficacy and Safety of Azilsartan in Adult Patients with Essential Hypertension: A Randomized, Phase-III Clinical Study in India.

BACKGROUND: Globally, women and men over the age of 25 years suffer from hypertension, the need for new treatment strategies to treat hypertension is due to the multi-faceted nature of the disease. Lack of optimal blood pressure control can lead to multiple complications. Therefore, this phase 3 study was conducted to assess the efficacy, safety and tolerability of potential product azilsartan hydrochloride for reduction in blood pressure in Indian patients with essential hypertension. METHODS: This was a prospective, multicentre, randomized, comparative, parallel study of 303 participants over six weeks of treatment period with either azilsartan 40 mg or azilsartan 80 mg or telmisartan 40 mg in adult patients with essential hypertension. The primary endpoint was the change in mean trough sitting clinic systolic blood pressure (scSBP) from baseline to week 6. The secondary endpoints were the change in mean trough sitting clinic diastolic blood pressure (scDBP) from baseline and change in the 24-hour mean ambulatory systolic blood pressure (SBP)and diastolic blood pressure (DBP) from baseline. RESULTS: The change in mean trough scSBP from baseline to week 6 was -27.2 ± 9.99, -28.2 ± 10.06 and -26.7 ± 9.72 (Per Patient (PP) Population) and -27.2 ± 9.93, -28.3 ± 10.01 and -26.7 ± 9.67 (Intent to Treat (ITT) Population) in the azilsartan 40mg, 80mg and telmisartan 40mg groups respectively. The lower limit of 95% CI of difference in change in mean systolic blood pressure was -2.35(Azilsartan 40mg) and 1.32 (Azilsartan 80mg) is less than the non-inferiority margin (i.e. 2.67). The change in mean trough scDBP from baseline to week 6 was -13.1 ± 8.46, -12.9 ± 7.20, and -13.0 ± 7.96 (PP) and -13.1 ± 8.42, -12.9 ± 7.16 and -13.0 ± 7.92 (ITT) in Azilsartna 40 mg, Azilsartan 80 mg and Telmisartan 40 mg respectively. The reduction in trough scDBP in Azilsartan 40 mg (p=0.9461: PP; p=0.9330: ITT) and Azilsartan 80 mg (p=0.9090: PP; p=0.9158: ITT) was not statistically significant compared to Telmisartan 40 mg. The difference in fall in the trough scSBP, scDBP and ambulatory SBP and DBP was similar between the groups from baseline to week 6 (P >0.05). Headache and dizziness were the most frequent treatmentrelated treatment-emergent adverse events. CONCLUSION: Azilsartan is an effective blood pressure lowering drug and well tolerated and was non- inferior to telmisartan in its safety and efficacy.

Chemokine SDF1 Mediated Bone Regeneration Using Biodegradable Poly(D,L-lactide-co-glycolide) 3D Scaffolds and Bone Marrow-Derived Mesenchymal Stem Cells: Implication for the Development of an "Off-the-Shelf" Pharmacologically Active Construct.

There is an increasing need for bone substitutes for reconstructive orthopedic surgery following removal of bone tumors. Despite the advances in bone regeneration, the use of autologous mesenchymal stem cells (MSC) presents a significant challenge, particularly for the treatment of large bone defects in cancer patients. This study aims at developing new chemokine-based technology to generate biodegradable scaffolds that bind pharmacologically active proteins for regeneration/repair of target injured tissues in patients. Primary MSC were cultured from the uninvolved bone marrow (BM) of cancer patients and further characterized for "stemness". Their ability to differentiate into an osteogenic lineage was studied in 2D cultures as well as on 3D macroporous PLGA scaffolds incorporated with biomacromolecules bFGF and homing factor chemokine stromal-cell derived factor-1 (SDF1). MSC from the uninvolved BM of cancer patients exhibited properties similar to that reported for MSC from BM of healthy individuals. Macroporous PLGA discs were prepared and characterized for pore size, architecture, functional groups, thermostability, and cytocompatibility by ESEM, FTIR, DSC, and CCK-8 dye proliferation assay, respectively. It was observed that the MSC+PLGA+bFGF+SDF1 construct cultured for 14 days supported significant cell growth, osteo-lineage differentiation with increased osteocalcin expression, alkaline phosphatase secretion, calcium mineralization, bone volume, and soluble IL6 compared to unseeded PLGA and PLGA+MSC, as analyzed by confocal microscopy, biochemistry, ESEM, microCT imaging, flow cytometry, and EDS. Thus, chemotactic biomacromolecule SDF1-guided tissue repair/regeneration ability of MSC from cancer patients opens up the avenues for development of "off-the-shelf" pharmacologically active construct for optimal repair of the target injured tissue in postsurgery cancer patients, bone defects, damaged bladder tissue, and radiation-induced skin/mucosal lesions.

Phase 1 study of PSMA ADC, an antibody-drug conjugate targeting prostate-specific membrane antigen, in chemotherapy-refractory prostate cancer.

BACKGROUND: Prostate-specific membrane antigen (PSMA) is a well-characterized target that is overexpressed selectively on prostate cancer cells. PSMA antibody-drug conjugate (ADC) is a fully human IgG1 monoclonal antibody conjugated to the microtubule disrupting agent monomethyl auristatin E (MMAE), which is designed to specifically bind PSMA-positive cells, internalize, and then release its cytotoxic payload into the cells. PSMA ADC has demonstrated potent and selective antitumor activity in preclinical models of advanced prostate cancer. A Phase 1 study was conducted to assess the safety, pharmacokinetics, and preliminary antitumor effects of PSMA ADC in subjects with treatment-refractory prostate cancer. METHODS: In this first-in-man dose-escalation study, PSMA ADC was administered by intravenous infusion every three weeks to subjects with progressive metastatic castration-resistant prostate cancer (mCRPC) who were previously treated with docetaxel chemotherapy. The primary endpoint was to establish a maximum tolerated dose (MTD). The study also examined the pharmacokinetics of the study drug, total antibody, and free MMAE. Antitumor effects were assessed by measuring changes in serum prostate-specific antigen (PSA), circulating tumor cells (CTCs), and radiologic imaging. RESULTS: Fifty-two subjects were administered doses ranging from 0.4 to 2.8 mg/kg. Subjects had a median of two prior chemotherapy regimens and prior treatment with abiraterone and/or enzalutamide. Neutropenia and peripheral neuropathy were identified as important first-cycle and late dose-limiting toxicities, respectively. The dose of 2.5 mg/kg was determined to be the MTD. Pharmacokinetics were approximately dose-proportional with minimal drug accumulation. Reductions in PSA and CTCs in subjects treated with doses of ≥1.8 mg/kg were durable and often concurrent. CONCLUSIONS: In an extensively pretreated mCRPC population, PSMA ADC demonstrated acceptable toxicity. Antitumor activity was observed over dose ranges up to and including 2.5 mg/kg. The observed anti-tumor activity supported further evaluation of this novel agent for the treatment of advanced metastatic prostate cancer.

Redox Sensitive Self-Assembling Dipeptide for Sustained Intracellular Drug Delivery.

The rational design and synthesis of molecules with functional supramolecular assemblies continues to be a challenging endeavor. Self-assembled nano- and microstructures from natural building blocks are considered more appropriate for medical applications due to their biocompatible nature. We report for the first time a simple redox-responsive dipeptide that self-assembles to form vesicles in aqueous medium. The experimental results based on the control compound and all-atom molecular dynamics (MD) simulations support the mechanism of association through intermolecular π-π interactions between the indole rings of tryptophan residues. These peptide vesicles showed a DOX loading capacity of ∼16% (w/w) and redox-triggered controlled release of the packaged drug. The drug-loaded vesicles were able to penetrate into MDA-MB-231 and HeLa cells, and release payload, suggesting their putative use as chemotherapeutic delivery vehicles. These natural peptide-based carriers disassemble inside cells due to the high cytosolic GSH concentration, and the resultant Cys-Trp dipeptide is degradable. The minimalistic peptide design presented here, coupled with the propensity to form vesicles that can encapsulate the chemotherapeutic drug, opens up unlimited potential for engineering targeted sustained-release drug delivery vehicles.

Understanding the Nature of Amino Acid Interactions with Pd(111) or Pd-Au Bimetallic Catalysts in the Aqueous Phase.

The interaction of methionine (Met) with different bimetallic-segregated surfaces comprising a uniform distribution of strips and islands of Au on the Pd(111) surface was examined using molecular dynamics (MD) simulations. Out of all the segregated and uniformly doped surfaces studied, the design of Pd-Au islands showed some reduction in the interaction energy (Eint = -43.7 kJ/mol) as compared to that of the pure Pd(111) surface (Eint = -50 kJ/mol) for a single Met molecule. However, at a higher coverage of 9 Met molecules/simulation cell, none of the Pd-Au alloy surfaces showed any improvement as compared to the Pd(111) surface. In order to develop a comprehensive understanding of the nature of the nonbonded interaction of aqueous biogenic impurities with the Pd catalyst surface, the MD study was extended to include a variety of aliphatic, S-containing, aromatic, and polar amino acids. The potential of mean force (PMF) profiles were observed to be distinct for each class of amino acids with substantial differences among amino acids with acidic and basic side chains. The side chains of all the polar and aromatic amino acids showed direct contact with the surface while aliphatic amino acids had their hydrophobic side chain aligned away from the surface. Interestingly, lysine (Lys) and tyrosine (Tyr) were the only two amino acids which interacted preferentially via the distant backbone nitrogen and backbone oxygen, respectively, despite their side chains being in direct contact with the metal surface. The strength of interaction was correlated with the size of the amino acid; the interaction energies were observed to be the maximum for large molecules such as arginine (Arg, Eint = -87.7 kJ/mol) and tryptophan (Trp, Eint = -73.4 kJ/mol), while it was a minimum for aliphatic amino acids such as alanine (Ala, Eint = -10.9 kJ/mol). The study is focused on examining the sensitivity of the choice of the preferential interaction site, conformational preferences, and interaction energies to the side-chain specificity.

Does Extracorporeal Irradiation and Reimplantation After Acetabular Resections Result in Adequate Hip Function? A Preliminary Report.

BACKGROUND: Pelvic resections are challenging, and reconstruction of the resected acetabulum to restore mobility and stability is even more difficult. Extracorporeal radiation therapy (ECRT or extracorporeal irradiation) of autograft bone and reimplantation allows for a perfect size match and has been used with some success in the extremities. Although the risk of wound complications in pelvic surgery has discouraged surgeons from using ECRT of autografts in that anatomic site, we believe it may be a reasonable option. QUESTIONS/PURPOSES: In a small series, we asked: (1) What was the median surgical time and blood loss for these procedures, and what early complications were observed? (2) Is there evidence of osteonecrosis or cartilage loss at a minimum of 2 years after ECRT of acetabular autografts, and what functional scores were achieved? (3) What were the oncologic outcomes after ECRT? METHODS: Between March 2007 and September 2016, one surgeon performed 12 ECRT acetabular autografts and reimplantations after resections of pelvic or acetabular tumors. Of those, 10 with minimum 2-year followup are reported on here with respect to oncologic, functional, and radiographic assessment; all 12 are reported on for purposes of surgical parameters and early complications. During that period, we generally performed this approach when we judged it possible to achieve a tumor-free margin, adequate bone stock, and sufficient remaining hip musculature to allow use of the bone as an autograft with restoration of hip mobility. We generally did not use this approach when we anticipated a difficult resection with uncertain margins or where remaining bone was judged of poor strength for use as a graft or if both iliopsoas and abductors were sacrificed. Since 2010, this series represents seven of the 21 pelvic resections with reconstruction that we performed (five patients in this series had the procedure performed before 2010). Followup was at a median of 65 months (range, 33-114 months) for nine patients whose functional outcomes were evaluated. The median patient age was 30 years (range, 10-64 years). Clinical parameters were recorded from chart review; radiographic analysis for assessment of cartilage was performed by looking for any obvious loss of joint space when compared with the opposite side. Functional scoring was done using the Musculoskeletal Tumor Society score, which was obtained from chart review. Oncologic assessment was determined for local recurrence as well as metastases. RESULTS: Median surgical time was 8.6 hours and median blood loss was 2250 mL. There were no perioperative wound-related complications. Two patients underwent a second surgical procedure during the postoperative period, one for a femoral artery thrombus and another for a complete sciatic nerve deficit. No patients developed avascular necrosis of the femoral head. None of the patients who underwent osteoarticular grafting showed radiographic evidence of joint space narrowing. The median Musculoskeletal Tumor Society score was 28 (range, 17-30). No fractures in the radiated segment of reimplanted bone were seen in this small series. CONCLUSIONS: Results from this small series suggest that ECRT is a potential option in selected patients who have good bone stock and adequate soft tissue coverage. Although technically challenging, ECRT is a low-cost alternative to prostheses in providing a mobile and stable hip. Although we did not observe cartilage wear on plain radiographs, followup here was short term; it may appear as we continue to follow these patients. Future studies from retrieval specimens may shed light on the actual status of cartilage on the acetabulum. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Does Denosumab Change the Giant Cell Tumor Treatment Strategy? Lessons Learned From Early Experience.

BACKGROUND: Although giant cell tumors (GCTs) are benign, their aggressiveness and tendency to recur locally challenge the orthopaedic surgeon's ability to perform joint-preserving intralesional surgery with an acceptably low risk of local recurrence. Denosumab has emerged as a possible medical treatment of GCT because it seems to halt the progression of GCT, alleviate pain, and increase perilesional bone formation, but its exact role has been questioned, and specifically its efficacy and associated complications are not well characterized. QUESTIONS/PURPOSES: (1) Does denosumab reduce the risk of recurrence after resection or intralesional surgery? (2) What are the complications associated with the use of denosumab? METHODS: Fifty-four patients with 30 primary and 25 recurrent tumors between November 2013 and July 2016 were treated with denosumab after a confirmed histopathologic diagnosis of GCT. Another 17 patients in the same period were treated without denosumab. During the study period, we encouraged the use of denosumab in all patients except those who refused, could not afford it, or where it was contraindicated (eg, in pregnancy). In all patients undergoing intralesional surgery, we arbitrarily planned six doses before surgery. Variations in total doses before surgery were dependent on patient-related factors; in some, we gave less doses because patients expressed the inability to afford any more doses, whereas in some patients, extra doses were added when the patient wished to delay surgery as well as the because of surgeon judgment wherein in some patients, we stopped before six doses when we thought adequate bone had formed for intralesional curettage. The mean number of doses was 6.8 per patient (median, 6; range, 3-17) preoperatively. The minimum followup was 12 months (median, 27 months; range, 12-42 months). Every patient showed improvement clinically in terms of pain and halting of tumor progression within three to four doses. This was seen radiologically as a sharply defined soft tissue mass as well as hazy ossification within the tumor. For a case-matched comparison study, we identified controls as 34 patients undergoing curettage from the retrospective analysis of 68 patients curetted without denosumab between February 2010 and July 2016 matched to 25 denosumab-treated patients in terms of site, size, Campanacci grade, and recurrent versus primary status, and with a minimum 2 years followup for the control group. Fisher's exact test was used for statistical study. Patients undergoing resection were planned for surgery after three doses of denosumab to allow the tumor to solidify and potentially decrease tumor spillage at the time of surgery. The resections could not be case-matched for comparison owing to the smaller numbers. RESULTS: We observed 14 recurrences out of the 37 curetted tumors (38%). In the case-matched analysis, 11 of 25 patients in the denosumab-treated curettage group had recurrences (44%) compared with seven of 34 (21%) in the nondenosumab-treated control group. The risk of denosumab-treated patients experiencing local recurrence as compared with the nondenosumab-treated patients was nonsignificant with a two-tailed p value of 0.085 (significance at p < 0.05) as derived from Fisher's exact test (odds ratio, 3.03; 95% confidence interval, 0.96-9.54). There was no recurrence in the resection group. Because we do not have a control group for resection, we are unable to comment on the importance of this finding. One major complication that we observed was a recurrence with malignant transformation in a patient with a proximal humeral GCT. We did not observe any other complications related to the denosumab therapy. CONCLUSIONS: Although we could not demonstrate a higher risk of local recurrence with preoperative denosumab for intralesional surgery in the dose and frequency we administered, we advise caution in its routine use for intralesional procedures because it may be important to curette up to margins on pretreatment imaging owing to the potential residual tumor within the denosumab-mediated thick bony shell, which may result in local recurrence. We believe that denosumab treatment before resection of a large tumor aids resection without tumor spillage, particularly where important structures like the neurovascular bundle are dissected away from the tumor margin, although we cannot confirm that it helps lower the incidence of recurrence. We are concerned regarding the malignancy-causing potential from our observation in one patient as well as reports of this by others and recommend judicious use of this drug in patients with GCT. LEVEL OF EVIDENCE: Level III, therapeutic study.

Effective interactions between nanoparticles: Creating temperature-independent solvation environments for self-assembly.

The extent to which solvent-mediated effective interactions between nanoparticles can be predicted based on structure and associated thermodynamic estimators for bulk solvents and for solvation of single and pairs of nanoparticles is studied here. As a test of the approach, we analyse the strategy for creating temperature-independent solvent environments using a series of homologous chain fluids as solvents, as suggested by an experimental paper [M. I. Bodnarchuk et al., J. Am. Chem. Soc. 132, 11967 (2010)]. Our conclusions are based on molecular dynamics simulations of Au140(SC10H21)62 nanoparticles in n-alkane solvents, specifically hexane, octane, decane and dodecane, using the TraPPE-UA potential to model the alkanes and alkylthiols. The 140-atom gold core of the nanocrystal is held rigid in a truncated octahedral geometry and the gold-thiolate interaction is modeled using a Morse potential. The experimental observation was that the structural and rheological properties of n-alkane solvents are constant over a temperature range determined by equivalent solvent vapour pressures. We show that this is a consequence of the fact that long chain alkane liquids behave to a good approximation as simple liquids formed by packing of monomeric methyl/methylene units. Over the corresponding temperature range (233-361 K), the solvation environment is approximately constant at the single and pair nanoparticle levels under good solvent conditions. However, quantitative variations of the order of 10%-20% do exist in various quantities, such as molar volume of solute at infinite dilution, entropy of solvation, and onset distance for soft repulsions. In the opposite limit of a poor solvent, represented by vacuum in this study, the effective interactions between nanoparticles are no longer temperature-independent with attractive interactions increasing by up to 50% on decreasing the temperature from 361 K to 290 K, accompanied by an increase in emergent anisotropy due to correlation of mass dipoles on the two nanoparticles. One expects therefore that during self-assembly using solvent evaporation, temperature can be used as a structure-directing factor as long as good solvent conditions are maintained. It also suggests that disordered configurations may emerge as solvent quality decreases due to increasing role of short-range attractions and ligand fluctuation-driven anisotropy. The possibilities of using structural estimators of various thermodynamic quantities to analyse the interplay of ligand fluctuations and solvent quality in self-assembly as well as to design solvation environments are discussed.

Pasteurization of bone for tumour eradication prior to reimplantation - an in vitro & pre-clinical efficacy study.

BACKGROUND & OBJECTIVES: In current era of limb-salvage therapy, pasteurization of bone sarcomas is receiving growing attention as a potential extracorporeal treatment and cost-effective alternative to allografts and radiation before surgical reimplantation. Detailed in vitro and in vivo pre-clinical study to evaluate efficacy of pasteurization to eradicate malignant cells has not been reported yet. The present study was carried out to assess the efficacy of pasteurization to kill tumour cells both in vitro and in vivo. METHODS: Surgically resected specimens of osteosarcomas (n=4) were cut into equal halves and one section was pasteurized by heating at 60°C to 65°C for 40 min. Paired samples before and after pasteurization were studied in vitro for DNA ploidy, evaluation of histological change and elimination of mitotic activity. These tissues were transplanted in immune-deficient NOD-SCID mice to evaluate effect on tumour-generating ability, presence of human nuclei, osteopontin and cytokine/chemokines released in tumour-transplanted mice. RESULTS: Non-pasteurized tumour samples had viable tumour cells which exhibited significant growth in culture, increased proliferative ability and clonogenic potential while respective pasteurized tumour tissues did not grow in culture and did not exhibit clonogenicity. Flow cytometry revealed that propidium iodide positive dead cells increased significantly (P< 0.01) post pasteurization. Seven of 12 non-pasteurized tumour transplanted mice demonstrated tumour-forming ability as against 0 of 12 in pasteurized tumour transplanted mice. Solid tumour xenografts exhibited strong expression of anti-human nuclei and osteopontin by immunohistochemistry as well as secretary human interluekin-6 (IL-6) while pasteurized mice failed to express these markers. INTERPRETATION & CONCLUSIONS: This study has provided a basis to establish pasteurization as being efficacious in ensuring tumour eradication from resected bone tumour specimens. Pasteurized tumour bearing bone can thus safely be used to reconstruct large defects after tumour resection.

Molecular Insights into the Inhibitory Role of α-Crystallin against γD-Crystallin Aggregation.

Cataracts, a major cause of global blindness, contribute significantly to the overall prevalence of blindness. The opacification of the lens, resulting in cataract formation, primarily occurs due to the aggregation of crystallin proteins within the eye lens. Despite the high concentration of these crystallins, they remarkably maintain the lens transparency and refractive index. α-Crystallins (α-crys), acting as chaperones, play a crucial role in preventing crystallin aggregation, although the exact molecular mechanism remains uncertain. In this study, we employed a combination of molecular docking, all-atom molecular dynamics simulations, and advanced free energy calculations to investigate the interaction between γD-crystallin (γD-crys), a major structural protein of the eye lens, and α-crystallin proteins. Our findings demonstrate that α-crys exhibits an enhanced affinity for the NTD2 and CTD4 regions of γD-crys. The NTD2 and CTD4 regions form the interface between the N-terminal domain (NTD) and the C-terminal domain (CTD) of the γD-crys protein. By binding to the interface region between the NTD and CTD of the protein, α-crys effectively inhibits the formation of domain-swapped aggregates and mitigates protein aggregation. Analysis of the Markov state models using molecular dynamics trajectories confirms that minimum free energy conformations correspond to the binding of the α-crystallin domain (ACD) of α-crys to NTD2 and CTD4 that form the interdomain interface.

Exploring Cu-Doped Co3O4 Bifunctional Oxygen Electrocatalysts for Aqueous Zn-Air Batteries.

The efficiency of oxygen electrocatalysis is a key factor in diverse energy domain applications, including the performance of metal-air batteries, such as aqueous Zinc (Zn)-air batteries. We demonstrate here that the doping of cobalt oxide with optimal amounts of copper (abbreviated as Cu-doped Co3O4) results in a stable and efficient bifunctional electrocatalyst for oxygen reduction (ORR) and evolution (OER) reactions in aqueous Zn-air batteries. At high Cu-doping concentrations (≥5%), phase segregation occurs with the simultaneous presence of Co3O4 and copper oxide (CuO). At Cu-doping concentrations ≤5%, the Cu ion resides in the octahedral (Oh) site of Co3O4, as revealed by X-ray diffraction (XRD)/Raman spectroscopy investigations and molecular dynamics (MD) calculations. The residence of Cu@Oh sites leads to an increased concentration of surface Co3+-ions (at catalytically active planes) and oxygen vacancies, which is beneficial for the OER. Temperature-dependent magnetization measurements reveal favorable d-orbital configuration (high eg occupancy ≈ 1) and a low → high spin-state transition of the Co3+-ions, which are beneficial for the ORR in the alkaline medium. The influence of Cu-doping on the ORR activity of Co3O4 is additionally accounted in DFT calculations via interactions between solvent water molecules and oxygen vacancies. The application of the bifunctional Cu-doped (≤5%) Co3O4 electrocatalyst resulted in an aqueous Zn-air battery with promising power density (=84 mW/cm2), stable cyclability (over 210 cycles), and low charge/discharge overpotential (=0.92 V).

Structure and energetics guide dynamic behaviour in a T = 3 icosahedral virus capsid.

Although virus capsids appear as rigid, symmetric particles in experimentally determined structures; biochemical studies suggest a significant degree of structural flexibility in the particles. We carried out all-atom simulations on the icosahedral capsid of an insect virus, Flock House Virus, which show intriguing differences in the degree of flexibility of quasi-equivalent capsid subunits consistent with previously described biological behaviour. The flexibility of all the ß and γ subunits of the protein and RNA fragments is analysed and compared. Both γA subunit and RNA fragment exhibit higher flexibility than the γB and γC subunits. The capsid shell is permeable to the bidirectional movement of water molecules, and the movement is heavily influenced by the geometry of the capsid shell along specific symmetry axes. In comparison to the symmetry axes along I5 and I3, the I2 axis exhibits a slightly higher water content. This enriched water environment along I2 could play a pivotal role in facilitating the structural transitions necessary for RNA release, shedding some light on the intricate and dynamic processes underlying the viral life cycle. Our study suggests that the physical characterization of whole virus capsids is the key to identifying biologically relevant transition states in the virus life cycle and understanding the basis of virus infectivity.

Groundwater quality assessment using water quality index and principal component analysis in the Achnera block, Agra district, Uttar Pradesh, Northern India.

The qualitative and quantitative assessment of groundwater is one of the important aspects for determining the suitability of potable water. Therefore, the present study has been performed to evaluate the groundwater quality for Achhnera block in the city of Taj, Agra, India, where groundwater is an important water resource. The groundwater samples, 50 in number were collected and analyzed for major ions along with some important trace element. This study has further investigated for the applicability of groundwater quality index (GWQI), and the principal component analysis (PCA) to mark out the major geochemical solutes responsible for origin and release of geochemical solutes into the groundwater. The results confirm that, majority of the collected groundwater samples were alkaline in nature. The variation of concentration of anions in collected groundwater samples were varied in the sequence as, HCO3- > Cl- > SO42- > F- while in contrast the sequence of cations in the groundwater as Na > Ca > Mg > K. The Piper diagram demonstrated the major hydro chemical facies which were found in groundwater (sodium bicarbonate or calcium chloride type). The plot of Schoellar diagram reconfirmed that the major cations were Na+ and Ca2+ ions, while in contrast; major anions were bicarbonates and chloride. The results showed water quality index mostly ranged between 105 and 185, hence, the study area fell in the category of unsuitable for drinking purpose category. The PCA showed pH, Na+, Ca2+, HCO3- and fluoride with strong loading, which pointed out geogenic source of fluoride contamination. Therefore, it was inferred that the groundwater of the contaminated areas must be treated and made potable before consumption. The outcomes of the present study will be helpful for the regulatory boards and policymaker for defining the actual impact and remediation goal.

Controversies in orthopaedic oncology.

Chondrosarcoma is the second most common surgically treated primary bone sarcoma. Despite a large number of scientific papers in the literature, there is still significant controversy about diagnostics, treatment of the primary tumour, subtypes, and complications. Therefore, consensus on its day-to-day treatment decisions is needed. In January 2024, the Birmingham Orthopaedic Oncology Meeting (BOOM) attempted to gain global consensus from 300 delegates from over 50 countries. The meeting focused on these critical areas and aimed to generate consensus statements based on evidence amalgamation and expert opinion from diverse geographical regions. In parallel, periprosthetic joint infection (PJI) in oncological reconstructions poses unique challenges due to factors such as adjuvant treatments, large exposures, and the complexity of surgery. The meeting debated two-stage revisions, antibiotic prophylaxis, managing acute PJI in patients undergoing chemotherapy, and defining the best strategies for wound management and allograft reconstruction. The objectives of the meeting extended beyond resolving immediate controversies. It sought to foster global collaboration among specialists attending the meeting, and to encourage future research projects to address unsolved dilemmas. By highlighting areas of disagreement and promoting collaborative research endeavours, this initiative aims to enhance treatment standards and potentially improve outcomes for patients globally. This paper sets out some of the controversies and questions that were debated in the meeting.

NCCP-ICS joint consensus-based clinical practice guidelines on medical thoracoscopy.

ABSTRACT: Medical Thoracoscopy (MT) is commonly performed by respiratory physicians for diagnostic as well as therapeutic purposes. The aim of the study was to provide evidence-based information regarding all aspects of MT, both as a diagnostic tool and therapeutic aid for pulmonologists across India. The consensus-based guidelines were formulated based on a multistep process using a set of 31 questions. A systematic search of published randomized controlled clinical trials, open labelled studies, case reports and guidelines from electronic databases, like PubMed, EmBase and Cochrane, was performed. The modified grade system was used (1, 2, 3 or usual practice point) to classify the quality of available evidence. Then, a multitude of factors were taken into account, such as volume of evidence, applicability and practicality for implementation to the target population and then strength of recommendation was finalized. MT helps to improve diagnosis and patient management, with reduced risk of post procedure complications. Trainees should perform at least 20 medical thoracoscopy procedures. The diagnostic yield of both rigid and semirigid techniques is comparable. Sterile-graded talc is the ideal agent for chemical pleurodesis. The consensus statement will help pulmonologists to adopt best evidence-based practices during MT for diagnostic and therapeutic purposes.