Comparative Evaluation of Microhardness and Polymerization Shrinkage in Residual Zirconia Reinforced Provisional Restorations: An In Vitro Study.

Aim The aim of this study is to evaluate and compare the microhardness and polymerization shrinkage of polymethyl methacrylate reinforced with residual zirconia. Materials and methods A total of 360 resin samples were fabricated, with dimensions of 12 mm × 12 mm × 3 mm and 12 mm × 8 mm × 6 mm. Zirconia dust (40% by weight) was added to 180 of these samples. The study included four groups: Group A (autopolymerizing acrylic resin), Group H (heat-polymerizing acrylic resin), Group ZA (autopolymerizing acrylic resin with zirconia dust), and Group ZH (heat-polymerizing acrylic resin with zirconia dust). Each group consisted of 90 samples, with 45 samples used for evaluating microhardness and 45 samples for assessing polymerization shrinkage. Results Group ZH exhibited the highest microhardness at 6.06 ± 0.31 GPa. It also recorded the lowest shrinkage values, measuring 52.11 ± 3.21 mm³. Tukey's honestly significant difference test revealed that microhardness was significantly higher in Group ZA (4.53 ± 0.29 GPa) compared to Group A (3.51 ± 0.25 GPa). However, Group H (5.42 ± 0.26 GPa) demonstrated greater hardness than Group ZA. Regarding shrinkage, the addition of zirconia dust resulted in reduced values, with Group ZA (73.93 ± 3.55 mm³) showing less shrinkage compared to Group A (91.9 ± 6.38 mm³). Similarly, Group ZH (52.11 ± 3.21 mm³) had lower shrinkage than Group H (66.71 ± 5.97 mm³). Group A exhibited the highest shrinkage among all the groups. Conclusion Within the limitations of this study, it can be concluded that there is an increase in hardness and a decrease in shrinkage values of the resin with the addition of zirconia dust in heat and autopolymerizing acrylic resin used for the fabrication of provisional restorations. Zirconia-incorporated heat-activated resin showed superior microhardness and decreased shrinkage values. Although the addition of residual zirconia to autopolymerized samples demonstrated better hardness, it was observed that pure heat-polymerized samples showed greater hardness. Reusing computer-aided design and computer-aided manufacturing powder waste can cut down on economic losses and aid in environmental sustainability.

Synthesis and Biological Evaluation of Colchicine─Aryl/Alkyl Amine Hybrids as Potential Noncytotoxic Cholinesterase Inhibitors: Identification of SBN-284 as a Dual Inhibitor of Cholinesterases and NLRP3 Inflammasome.

Colchicine, one of the oldest anti-inflammatory natural products still used clinically, inhibits NF-κB signaling and NLRP3 inflammasome activation. Despite its cytotoxicity and narrow therapeutic range, colchicine continues to intrigue medicinal chemists exploring its anti-inflammatory potential. This study aimed to investigate the colchicine scaffold for its role in Alzheimer's disease by targeting neuroinflammation and cholinesterases. Molecular docking revealed that colchicine's hydrophobic trimethoxyphenyl framework can potentially bind to the peripheral anionic site of cholinesterases. Hybrid structures combining colchicine with aryl/alkyl amines were designed to bind both peripheral and catalytic sites of cholinesterases. We describe here the design, synthesis, and in vitro cytotoxicity evaluation of these colchicine-aryl/alkyl amine hybrids, along with their in silico interactions with the cholinesterase active site gorge. Nontoxic analogs demonstrating strong cholinesterase binding affinity were further evaluated for their anticholinesterase and antineuroinflammatory activities. The colchicine-donepezil hybrid, SBN-284 (3x), inhibited both acetylcholinesterase and butyrylcholinesterase as well as the NLRP3 inflammasome complex at low micromolar concentrations. It achieved this through noncompetitive inhibition, occupying the active site gorge and interacting with both peripheral and catalytic anionic sites of cholinesterases. Analog 3x was shown to cross the blood-brain barrier and exhibited no toxicity to neuronal cells, primary macrophages, or epithelial fR2 cells. These findings highlight the potential of this lead compound for further preclinical investigation as a promising anti-Alzheimer agent.

Effectiveness of respiratory face masks in reducing acute PM2.5 pollution exposure during peak pollution period in Delhi.

The cities of North India, such as Delhi, face a significant public health threat from severe air pollution. Between October 2021 and January 2022, 79 % of Delhi's daily average PM2.5 (Particulate matter with an aerodynamic diameter ≤ 2.5 µm) values exceeded 100 µg/m3 (the permissible level being 60 µg/m3 as per Indian standards). In response to this acute exposure, using Respiratory Face Masks (RFMs) is a cost-effective solution to reduce immediate health risks while policymakers develop long-term emission control plans. Our research focuses on the health and economic benefits of using RFMs to prevent acute exposure to PM2.5 pollution in Delhi for different age groups. Our findings indicate that, among the fifty chosen RFMs, M50 has greatest potential to prevent short-term excess mortality (908 in age ranges 5-44), followed by M49 (745) and M48 (568). These RFMs resulted in estimated economic benefits of 500.6 (46 %), 411.1 (37 %), and 313.4 (29 %) million Indian Rupee (INR), respectively during October-January 2021-22. By wearing RFMs such as M50, M49, and M48 during episodes of bad air quality, it is estimated that 13 % of short-term excess mortality and associated costs could be saved if at least 30 % of Delhi residents followed an alert issued by an operational Air Quality Early Warning System (AQEWS) developed by the Ministry of Earth Sciences. Our research suggests that RFMs can notably decrease health and economic burdens amid peak PM2.5 pollution in post-monsoon and winter seasons until long-term emission reduction strategies are adopted. It is suggested that an advisory may be crafted in collaboration with statutory bodies and should be disseminated to assist the vulnerable population in using RFMs during winter. The analysis presented in this research is purely science based and outcomes of study are in no way to be construed as endorsement of product.

Modes of action and potential as a peptide-based biofungicide of a plant defensin MtDef4.

Due to rapidly emerging resistance to single-site fungicides in fungal pathogens of plants, there is a burgeoning need for safe and multisite fungicides. Plant antifungal peptides with multisite modes of action (MoA) have potential as bioinspired fungicides. Medicago truncatula defensin MtDef4 was previously reported to exhibit potent antifungal activity against fungal pathogens. Its MoA involves plasma membrane disruption and binding to intracellular targets. However, specific biochemical processes inhibited by this defensin and causing cell death have not been determined. Here, we show that MtDef4 exhibited potent antifungal activity against Botrytis cinerea. It induced severe plasma membrane and organelle irregularities in the germlings of this pathogen. It bound to fungal ribosomes and inhibited protein translation in vitro. A MtDef4 variant lacking antifungal activity exhibited greatly reduced protein translation inhibitory activity. A cation-tolerant MtDef4 variant was generated that bound to ß-glucan of the fungal cell wall with higher affinity than MtDef4. It also conferred a greater reduction in the grey mould disease symptoms than MtDef4 when applied exogenously on Nicotiana benthamiana plants, tomato fruits and rose petals. Our findings revealed inhibition of protein synthesis as a likely target of MtDef4 and the potential of its cation-tolerant variant as a peptide-based fungicide.

Costunosides A-C: cytotoxic sesquiterpene lactones from the rhizomes of Aucklandia costus Falc.

Three new eudesmane type rare sesquiterpene lactone galactosides, costunosides A-C (1-3) were isolated from the rhizomes of Aucklandia costus along with ten known compounds (4-13). Costunosides A-C (1-3) are the first example of naturally eudesmane glycosides containing a ß-galactopyranoside moiety. The structure and relative configurations of these compounds were established by comprehensive analysis of MS and, in particular 1D/2D NMR spectroscopic data. The isolated compounds were tested against a panel of human cancer cell lines, where compounds 3, 6 and 7 have shown promising cytotoxic activity against PC-3, HCT-116 and A549 cell lines with IC50 values in the range of 3.4 µM to 9.3 µM, respectively. Costunosides A-C (1-3) were also screened for inhibition assay of acetyl-cholinesterase (AChE), and butyrylcholinesterase (BChE) and found inactive at a concentration of 10 µM.

Apoptotic Potential and Antitumor Efficacy of Trilliumoside A: A New Steroidal Saponin Isolated from Rhizomes of Trillium govanianum.

Natural product-derived molecules exhibit potential as anticancer agents. Trilliumoside A, a new steroidal saponin, was obtained from rhizomes of Trillium govanianum, and its anticancer activity was investigated in the presented study. Trilliumoside A was investigated in a panel of cell lines, and it exhibited promising cytotoxic activity on the A549 cells (human lung cancer cells) with an IC50 of 1.83 µM. The mechanism of cell death induced by Trilliumoside A in A549 cells and its anticancer potential in murine tumor models (EAC and EAT) were presented in the current research. Trilliumoside A was found to induce apoptosis in A549 cells by increasing the expression of various apoptotic proteins, such as Bax, Puma, cytochrome C, cleaved PARP, and cleaved caspase 3. Additionally, Trilliumoside A regulates the expression of p53, CDK2, and Cyclin A by decreasing the mitochondrial membrane potential, elevating reactive oxygen species, and stopping the growth of A549 cells in the synthesis phase (S) of the cell cycle. Trilliumoside A showed a considerable reduction in the tumor volume, the amount of ascitic fluid, and the total cell number without affecting the body weight of animals. Our results demonstrate that Trilliumoside A inhibits the proliferation of human lung cancer cells by inducing DNA damage, arresting the cell cycle, and activating the mitochondrial signaling pathway. The study demonstrated the potential of Trilliumoside A as a potential anticancer agent.

Small Cationic Cysteine-Rich Defensin-Derived Antifungal Peptide Controls White Mold in Soybean.

White mold disease caused by a necrotrophic ascomycete pathogen Sclerotinia sclerotiorum results in serious economic losses of soybean yield in the USA. Lack of effective genetic resistance to this disease in soybean germplasm and increasing pathogen resistance to fungicides makes white mold difficult to manage. Small cysteine-rich antifungal peptides with multi-faceted modes of action possess potential for development as sustainable spray-on bio-fungicides. We have previously reported that GMA4CG_V6 peptide, a 17-amino acid variant of the MtDef4 defensin-derived peptide GMA4CG containing the active γ-core motif, exhibits potent antifungal activity against the gray mold fungal pathogen Botrytis cinerea in vitro and in planta. GMA4CG_V6 exhibited antifungal activity against an aggressive field isolate of S. sclerotiorum 555 in vitro with an MIC value of 24 µM. At this concentration, internalization of this peptide into fungal cells occurred prior to discernible membrane permeabilization. GMA4CG_V6 markedly reduced white mold disease symptoms when applied to detached soybean leaves, pods, and stems. Its spray application on soybean plants provided robust control of this disease. GMA4CG_V6 at sub-lethal concentrations reduced sclerotia production. It was also non-phytotoxic to soybean plants. Our results demonstrate that GMA4CG_V6 peptide has potential for development as a bio-fungicide for white mold control in soybean.

Antifibrotic Agent Mediated Tumor Microenvironment Modulation and Improved Nanomedicine Delivery in Solid Tumor.

The unique physiology of tumors limits the efficacy of chemotherapeutics. In efforts to improve the effectiveness of the existing chemotherapy drugs, nanomedicine emerged as a new hope but proved inadequate due to the transport barriers present within the tumor tissues, which limits the potential of nanomedicine. Dense collagen networks in fibrotic tissues contribute to hindering the penetration of molecular- or nano-scale medicine through tumor interstitium. In the present study, human serum albumin (HSA)-based nanoparticles (NPs) were developed for gemcitabine (GEM) and losartan (LST), which could offer secreted protein acids rich in cysteine (SPARC) and enhanced permeability and retention effect (EPR)-mediated drug accumulation in tumors. Also, the tumor microenvironment (TME) modulation approach using LST was coupled to investigate the impact on antitumor efficacy. GEM-HSA NPs and LST-HSA NPs were prepared by the desolvation-cross-linking method and characterized for size, potential, morphology, drug loading, drug-polymer interactions, and hemocompatibility. For investigating the efficacy of prepared NPs, cytotoxicity and mechanisms of cell death were elucidated in vitro by using various assays. Intracellular uptake studies of prepared HSA NPs indicated their uptake and cytoplasmic localization. Furthermore, in vivo studies demonstrated significantly improved anticancer efficacy of GEM-HSA NPs in combination with LST pretreatment. Extended LST treatment further improved the anticancer potential. It was shown that the improved efficacy of the nanomedicine was correlated with the reduced thrombospondin-1 (TSP-1) and collagen level in tumor tissue upon LST pretreatment. Moreover, this approach exhibited augmented nanomedicine accumulation in the tumor, and hematological, biochemical, and tissue histology indicated the safety profile of this combination regimen. Concisely, the undertaken study demonstrated the potential of the triple targeting (SPARC, EPR, TME modulation) approach for augmented efficacy of chemotherapeutics.

Plant defensin MtDef4-derived antifungal peptide with multiple modes of action and potential as a bio-inspired fungicide.

Chemical fungicides have been instrumental in protecting crops from fungal diseases. However, increasing fungal resistance to many of the single-site chemical fungicides calls for the development of new antifungal agents with novel modes of action (MoA). The sequence-divergent cysteine-rich antifungal defensins with multisite MoA are promising starting templates for design of novel peptide-based fungicides. Here, we experimentally tested such a set of 17-amino-acid peptides containing the γ-core motif of the antifungal plant defensin MtDef4. These designed peptides exhibited antifungal properties different from those of MtDef4. Focused analysis of a lead peptide, GMA4CG_V6, showed that it was a random coil in solution with little or no secondary structure elements. Additionally, it exhibited potent cation-tolerant antifungal activity against the plant fungal pathogen Botrytis cinerea, the causal agent of grey mould disease in fruits and vegetables. Its multisite MoA involved localization predominantly to the plasma membrane, permeabilization of the plasma membrane, rapid internalization into the vacuole and cytoplasm, and affinity for the bioactive phosphoinositides phosphatidylinositol 3-phosphate (PI3P), PI4P, and PI5P. The sequence motif RRRW was identified as a major determinant of the antifungal activity of this peptide. While topical spray application of GMA4CG_V6 on Nicotiana benthamiana and tomato plants provided preventive and curative suppression of grey mould disease symptoms, the peptide was not internalized into plant cells. Our findings open the possibility that truncated and modified defensin-derived peptides containing the γ-core sequence could serve as promising candidates for further development of bio-inspired fungicides.

In vitro and in vivo anticancer potential and molecular targets of the new colchicine analog IIIM-067.

OBJECTIVE: The current study evaluated various new colchicine analogs for their anticancer activity and to study the primary mechanism of apoptosis and in vivo antitumor activity of the analogs with selective anticancer properties and minimal toxicity to normal cells. METHODS: Sulforhodamine B (SRB) assay was used to screen various colchicine analogs for their in vitro cytotoxicity. The effect of N-[(7S)-1,2,3-trimethoxy-9-oxo-10-(pyrrolidine-1-yl)5,6,7,9-tetrahydrobenzo[a] heptalene-7-yl] acetamide (IIIM-067) on clonogenicity, apoptotic induction, and invasiveness of A549 cells was determined using a clonogenic assay, scratch assay, and staining with 4',6-diamidino-2-phenylindole (DAPI) and annexin V/propidium iodide. Mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) levels were observed using fluorescence microscopy. Western blot analysis was used to quantify expression of proteins involved in apoptosis, cell cycle, and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling. Pharmacokinetic and in vivo efficacy studies against Ehrlich ascites carcinoma (EAC) and Ehrlich solid tumor models were conducted using Swiss albino mice. RESULTS: IIIM-067 showed potent cytotoxicity and better selectivity than all other colchicine analogs screened in this study. The selective activity of IIIM-067 toward A549 cells was higher among other cancer cell lines, with a selectivity index (SI) value of 2.28. IIIM-067 demonstrated concentration- and time-dependent cytotoxicity against A549 cells with half-maximal inhibitory concentration values of 0.207, 0.150 and 0.106 µmol/L at 24, 48 and 72 h, respectively. It also had reduced toxicity to normal cells (SI > 1) than the parent compound colchicine (SI = 1). IIIM-067 reduced the clonogenic ability of A549 cells in a dose-dependent manner. IIIM-067 enhanced ROS production from 24.6% at 0.05 µmol/L to 82.1% at 0.4 µmol/L and substantially decreased the MMP (100% in control to 5.6% at 0.4 µmol/L). The annexin V-FITC assay demonstrated 78% apoptosis at 0.4 µmol/L. IIIM-067 significantly (P < 0.5) induced the expression of various intrinsic apoptotic pathway proteins, and it differentially regulated the PI3K/AKT/mTOR signaling pathway. Furthermore, IIIM-067 exhibited remarkable in vivo anticancer activity against the murine EAC model, with tumor growth inhibition (TGI) of 67.0% at a dose of 6 mg/kg (i.p.) and a reduced mortality compared to colchicine. IIIM-067 also effectively inhibited the tumor growth in the murine solid tumor model with TGI rates of 48.10%, 55.68% and 44.00% at doses of 5 mg/kg (i.p.), 6 mg/kg (i.p.) and 7 mg/kg (p.o.), respectively. CONCLUSION: IIIM-067 exhibited significant anticancer activity with reduced toxicity both in vitro and in vivo and is a promising anticancer candidate. However, further studies are required in clinical settings to fully understand its potential.

In vitro and in vivo anticancer potential and molecular targets of the new colchicine analog IIIM-067 / 中西医结合学报

OBJECTIVE@#The current study evaluated various new colchicine analogs for their anticancer activity and to study the primary mechanism of apoptosis and in vivo antitumor activity of the analogs with selective anticancer properties and minimal toxicity to normal cells.@*METHODS@#Sulforhodamine B (SRB) assay was used to screen various colchicine analogs for their in vitro cytotoxicity. The effect of N-[(7S)-1,2,3-trimethoxy-9-oxo-10-(pyrrolidine-1-yl)5,6,7,9-tetrahydrobenzo[a] heptalene-7-yl] acetamide (IIIM-067) on clonogenicity, apoptotic induction, and invasiveness of A549 cells was determined using a clonogenic assay, scratch assay, and staining with 4',6-diamidino-2-phenylindole (DAPI) and annexin V/propidium iodide. Mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) levels were observed using fluorescence microscopy. Western blot analysis was used to quantify expression of proteins involved in apoptosis, cell cycle, and phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) signaling. Pharmacokinetic and in vivo efficacy studies against Ehrlich ascites carcinoma (EAC) and Ehrlich solid tumor models were conducted using Swiss albino mice.@*RESULTS@#IIIM-067 showed potent cytotoxicity and better selectivity than all other colchicine analogs screened in this study. The selective activity of IIIM-067 toward A549 cells was higher among other cancer cell lines, with a selectivity index (SI) value of 2.28. IIIM-067 demonstrated concentration- and time-dependent cytotoxicity against A549 cells with half-maximal inhibitory concentration values of 0.207, 0.150 and 0.106 μmol/L at 24, 48 and 72 h, respectively. It also had reduced toxicity to normal cells (SI > 1) than the parent compound colchicine (SI = 1). IIIM-067 reduced the clonogenic ability of A549 cells in a dose-dependent manner. IIIM-067 enhanced ROS production from 24.6% at 0.05 μmol/L to 82.1% at 0.4 μmol/L and substantially decreased the MMP (100% in control to 5.6% at 0.4 μmol/L). The annexin V-FITC assay demonstrated 78% apoptosis at 0.4 μmol/L. IIIM-067 significantly (P < 0.5) induced the expression of various intrinsic apoptotic pathway proteins, and it differentially regulated the PI3K/AKT/mTOR signaling pathway. Furthermore, IIIM-067 exhibited remarkable in vivo anticancer activity against the murine EAC model, with tumor growth inhibition (TGI) of 67.0% at a dose of 6 mg/kg (i.p.) and a reduced mortality compared to colchicine. IIIM-067 also effectively inhibited the tumor growth in the murine solid tumor model with TGI rates of 48.10%, 55.68% and 44.00% at doses of 5 mg/kg (i.p.), 6 mg/kg (i.p.) and 7 mg/kg (p.o.), respectively.@*CONCLUSION@#IIIM-067 exhibited significant anticancer activity with reduced toxicity both in vitro and in vivo and is a promising anticancer candidate. However, further studies are required in clinical settings to fully understand its potential.

COVID-19 associated multisystemic mucormycosis from India: a multicentric retrospective study on clinical profile, predisposing factors, cumulative mortality and factors affecting outcome.

PURPOSE: The clinical course of COVID-19 has been complicated by secondary infections, including bacterial and fungal infections. The rapid rise in the incidence of invasive mucormycosis in these patients is very much concerning. COVID-19-associated mucormycosis was detected in huge numbers during the second wave of the COVID-19 pandemic in India, with several predisposing factors indicated in its pathogenesis. This study aimed to evaluate the epidemiology, predisposing factor, cumulative mortality and factors affecting outcomes among the coronavirus disease COVID-19-associated mucormycosis (CAM). METHODS: A multicenter retrospective study across three tertiary health care centers in Southern part of India was conducted during April-June 2021. RESULTS: Among the 217 cases of CAM, mucormycosis affecting the nasal sinuses was the commonest, affecting 95 (44%) of the patients, orbital extension seen in 84 (38%), pulmonary (n = 25, 12%), gastrointestinal (n = 6, 3%), isolated cerebral (n = 2) and disseminated mucormycosis (n = 2). Diabetes mellitus, high-dose systemic steroids were the most common underlying disease among CAM patients. The mucormycosis-associated case-fatality at 6 weeks was 14%, cerebral or GI or disseminated mucormycosis had 9 times higher risk of death compared to other locations. Extensive surgical debridement along with sequential antifungal drug treatment improved the survival in mucormycosis patients. CONCLUSION: Judicious and appropriate management of the predisposing factor and factors affecting mortality associated with CAM with multi-disciplinary approach and timely surgical and medical management can be much helpful in achieving a successful outcome.

Implication of methylselenocysteine in combination chemotherapy with gemcitabine for improved anticancer efficacy.

The limitations associated with cancer monotherapy including dose dependent toxicity and drug resistance can be addressed by combination chemotherapy. The combination of antineoplastic agents improves the cytotoxic activity in comparison to the single-agent based therapy in a synergistic or an additive mode by reducing tumor growth as well as metastatic ability. In the present investigation, we explored the potential of methylselenocysteine (MSC) in combination chemotherapy with gemcitabine (GEM). The cytotoxic activity of GEM and MSC was determined in various cell lines and based on the activity, A549 cells were explored for the mechanistic studies including DAPI staining, measurement of oxidative stress, mitochondrial membrane potential loss, nitric oxide level, western blotting, cell migration and colony formation assays. A549 cells in combination treatment with MSC and GEM demonstrated enhanced cytotoxicity with more irregular cellular morphology as well as chromatin condensation and nuclear blebbing. The selected combination also significantly triggered ROS generation and mitochondrial destabilization, and alleviated cell migration potential and clonogenic propensity of A549 cells. Also, caspase-3 and PARP mediated apoptosis was observed in the combination treated cells. MSC based drug combination could offer the attributes of improved drug delivery and there was a 6-folds dose reduction of GEM in combination. Further, antitumor study in Ehrlich solid tumor model showed the efficacy of MSC combination with GEM for the enhanced antitumor activity. The proposed combination demonstrated the potential for further translational studies.

An improved synthesis of indanocine and antiproliferative activity of 2-benzylindanocine via microtubule destabilization.

Indanocine, a potent anticancer investigational drug of National Cancer Institute-USA, has been much discussed in recent years. Present communication aimed at total synthesis of indanocine and its close analogues. Total synthesis was improved by double yields than previously reported yields. Some of the benzylidene and 2-benzyl derivatives with free rotation at C2 position exhibited potential cytotoxicities against various human cancer cell lines. Five such analogues exhibited potential antiproliferative effect against HCT-116 and MIA PACA-2 cell lines. Benzylindanocine 12i induced microtubule destabilization by occupying colchicine binding pocket of ß-tubulin. It also exhibited anti-inflammatory activity by down-regulating IL-6 and TNF-α. In Ehrlich ascites carcinoma model, 12i reduced 78.4% of EAC tumour in Swiss albino mice at 90 mg/kg (i.p.) dose. Further, in in vivo safety studies, 12i was found to be safe to rodents up to 1,000 mg/kg dose. Concomitant anticancer and anti-inflammatory activity of benzylindanocine is distinctive, which suggests its further optimization for better efficacy and druggability.

Antifungal symbiotic peptide NCR044 exhibits unique structure and multifaceted mechanisms of action that confer plant protection.

In the indeterminate nodules of a model legume Medicago truncatula, ∼700 nodule-specific cysteine-rich (NCR) peptides with conserved cysteine signature are expressed. NCR peptides are highly diverse in sequence, and some of these cationic peptides exhibit antimicrobial activity in vitro and in vivo. However, there is a lack of knowledge regarding their structural architecture, antifungal activity, and modes of action against plant fungal pathogens. Here, the three-dimensional NMR structure of the 36-amino acid NCR044 peptide was solved. This unique structure was largely disordered and highly dynamic with one four-residue α-helix and one three-residue antiparallel ß-sheet stabilized by two disulfide bonds. NCR044 peptide also exhibited potent fungicidal activity against multiple plant fungal pathogens, including Botrytis cinerea and three Fusarium spp. It inhibited germination in quiescent spores of B. cinerea In germlings, it breached the fungal plasma membrane and induced reactive oxygen species. It bound to multiple bioactive phosphoinositides in vitro. Time-lapse confocal and superresolution microscopy revealed strong fungal cell wall binding, penetration of the cell membrane at discrete foci, followed by gradual loss of turgor, subsequent accumulation in the cytoplasm, and elevated levels in nucleoli of germlings. Spray-applied NCR044 significantly reduced gray mold disease symptoms caused by the fungal pathogen B. cinerea in tomato and tobacco plants, and postharvest products. Our work illustrates the antifungal activity of a structurally unique NCR peptide against plant fungal pathogens and paves the way for future development of this class of peptides as a spray-on fungistat/fungicide.

Binary and ternary solid dispersions of an anticancer preclinical lead, IIIM-290: In vitro and in vivo studies.

The objective of this study was to formulate an anticancer preclinical lead, IIIM-290, loaded in solid dispersions to enhance its solubility, dissolution, and oral pharmacokinetics. IIIM-290 is an in-house preclinical anticancer lead prepared by semisynthetic modification of the natural product rohitukine. It is an orally bioavailable Cdk inhibitor showing efficacy in xenograft models of pancreatic, colon and leukemia cancer. It demonstrated in vivo efficacy at a relatively higher dose owing to its poor aqueous solubility (~8.6 µg/mL). Binary and ternary solid dispersions containing PVP K-30, xanthan gum, and PEG-PPG-PEG were selected after solubility screening of various hydrophilic polymers. Several formulations with varying ratios of polymers, alone and in combination, were prepared and investigated for their effects on the solubility enhancement of IIIM-290. The binary solid dispersion VKB-SD75, prepared with PVP K-30 at the ratio of 1:4 w/w, was identified as the optimized composition that displayed 17-fold improvement in the aqueous solubility of IIIM-290. VKB-SD75 was scaled up to a 100-g scale. IIIM-290 and VKB-SD75 were evaluated for DSC, p-XRD, FTIR, 1H NMR, SEM, in vitro dissolution, and oral pharmacokinetics, as well as for in vivo anticancer activity in the Ehrlich solid tumor model. The oral administration of VKB-SD75 in BALB/c mice resulted in a 1.9-fold improvement in plasma exposure. These findings also correlated well when the formulation was administered to mice in the Ehrlich solid tumor model. The newly developed solid dispersion is expected to reduce the dose of IIIM-290 by ~40-50% in preclinical and clinical studies.