Rapid Virucidal Activity of Japanese Saxifraga Species-Derived Condensed Tannins against SARS-CoV-2, Influenza A Virus, and Human Norovirus Surrogate Viruses.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza A virus (IAV), and norovirus are global threats to human health. The application of effective virucidal agents, which contribute to the inactivation of viruses on hands and environmental surfaces, is important to facilitate robust virus infection control measures. Naturally derived virucidal disinfectants have attracted attention owing to their safety and eco-friendly properties. In this study, we showed that multiple Japanese Saxifraga species-derived fractions demonstrated rapid, potent virucidal activity against the SARS-CoV-2 ancestral strain and multiple variant strains, IAV, and two human norovirus surrogates: feline calicivirus (FCV) and murine norovirus (MNV). Condensed tannins were identified as active chemical constituents that play a central role in the virucidal activities of these fractions. At a concentration of 25 µg/mL, the purified condensed tannin fraction Sst-2R induced significant reductions in the viral titers of the SARS-CoV-2 ancestral strain, IAV, and FCV (reductions of ≥3.13, ≥3.00, and 2.50 log10 50% tissue culture infective doses [TCID50]/mL, respectively) within 10 s of reaction time. Furthermore, at a concentration of 100 µg/mL, Sst-2R induced a reduction of 1.75 log10 TCID50/mL in the viral titers of MNV within 1 min. Western blotting and transmission electron microscopy analyses revealed that Sst-2R produced structural abnormalities in viral structural proteins and envelopes, resulting in the destruction of viral particles. Furthermore, Saxifraga species-derived fraction-containing cream showed virucidal activity against multiple viruses within 10 min. Our findings indicate that Saxifraga species-derived fractions containing condensed tannins can be used as disinfectants against multiple viruses on hands and environmental surfaces. IMPORTANCE SARS-CoV-2, IAV, and norovirus are highly contagious pathogens. The use of naturally derived components as novel virucidal/antiviral agents is currently attracting attention. We showed that fractions from extracts of Saxifraga species, in the form of a solution as well as a cream, exerted potent, rapid virucidal activities against SARS-CoV-2, IAV, and surrogates of human norovirus. Condensed tannins were found to play a central role in this activity. The in vitro cytotoxicity of the purified condensed tannin fraction at a concentration that exhibited some extent of virucidal activity was lower than that of 70% ethanol or 2,000 ppm sodium hypochlorite solution, which are popular virucidal disinfectants. Our study suggests that Saxifraga species-derived fractions containing condensed tannins can be used on hands and environmental surfaces as safe virucidal agents against multiple viruses.

Benzophenone Glucosides and B-Type Proanthocyanidin Dimers from Zambian Cassia abbreviata and Their Trypanocidal Activities.

Two benzophenone glucosides (1 and 2), five flavan-3-ol dimers (5-9), and 17 known compounds (3, 4, and 10-24) were identified from the bark extract of Cassia abbreviata. The chemical structures display two points of interest. First, as an unusual characteristic feature of the 1H NMR spectra of 1 and 2, the signals for the protons on glucosidic carbons C-2 are shielded as compared to those generally observed for glucosyl moieties. The geometrically optimized 3D structures derived from conformational analysis and density functional theory (DFT) calculations revealed that this shielding effect originates from intramolecular hydrogen bonds in 1 and 2. Additionally, 3-15 were identified as dimeric B-type proanthocyanidins, which have 2R,3S-absolute-configured C-rings and C-4-C-8″ linkages, as evidenced by X-ray crystallography and by NMR and ECD spectroscopy. These results suggest the structure-determining procedures for some reported dimers need to be reconsidered. The trypanocidal activities of the isolated compounds against Trypanosoma brucei brucei, T. b. gambiense, T. b. rhodesiense, T. congolense, and T. evansi were evaluated, and the active compounds were identified.

Preoperative prognostic nutritional index predicts postoperative infectious complications and oncological outcomes after hepatectomy in intrahepatic cholangiocarcinoma.

BACKGROUND: In the surgical treatment of intrahepatic cholangiocarcinoma (ICC), postoperative complications may be predictive of long-term survival. This study aimed to identify an immune-nutritional index (INI) that can be used for preoperative prediction of complications. PATIENTS AND METHODS: Multi-institutional data from 316 patients with ICC who had undergone surgical resection were retrospectively analysed, with a focus on various preoperative INIs. RESULTS: Severe complications (Clavien-Dindo grade III-V) were identified in 66 patients (20.8%), including Grade V complications in 7 patients (2.2%). Comparison of areas under the receiver operating characteristic curve (AUCs) among various INIs identified the prognostic nutritional index (PNI) as offering the highest predictive value for severe complications (AUC = 0.609, cut-off = 50, P = 0.008). Multivariate analysis revealed PNI <  50 (odds ratio [OR] = 2.22, P = 0.013), hilar lesion (OR = 2.46, P = 0.026), and long operation time (OR = 1.003, P = 0.029) as independent risk factors for severe complications. In comparing a high-PNI group (PNI ≥ 50, n = 142) and a low-PNI group (PNI <  50, n = 174), the low-PNI group showed higher rates of both major complications (27% vs. 13.4%; P = 0.003) and infectious complications (14.9% vs. 3.5%; P = 0.0021). Furthermore, median survival time and 1- and 5-year overall survival rates were 34.2 months and 77.4 and 33.8% in the low-PNI group, respectively, and 52.4 months and 89.3 and 47.5% in the high-PNI group, respectively (P = 0.0017). CONCLUSION: Preoperative PNI appears useful as an INI correlating with postoperative severe complications and as a prognostic indicator for ICC.

Synthesis and evaluation of trypanocidal activity of derivatives of naturally occurring 2,5-diphenyloxazoles.

African trypanosomiasis is a zoonotic protozoan disease affecting the nervous system. Various natural products reportedly exhibit trypanocidal activity. Naturally occurring 2,5-diphenyloxazoles present in Oxytropis lanata, and their derivatives, were synthesized. The trypanocidal activities of the synthesized compounds were evaluated against Trypanosoma brucei brucei, T. b. gambiense, T. b. rhodesiense, T. congolense, and T. evansi. Natural product 1 exhibited trypanocidal activity against all the species/subspecies of trypanosomes, exhibiting half-maximal inhibitory concentrations (IC50) of 1.1-13.5 µM. Modification of the oxazole core improved the trypanocidal activity. The 1,3,4-oxadiazole (7) and 2,4-diphenyloxazole (9) analogs exhibited potency superior to that of 1. However, these compounds exhibited cytotoxicity in Madin-Darby bovine kidney cells. The O-methylated analog of 1 (12) was non-cytotoxic and exhibited selective trypanocidal activity against T. congolense (IC50 = 0.78 µM). Structure-activity relationship studies of the 2,5-diphenyloxazole analogs revealed aspects of the molecular structure critical for maintaining selective trypanocidal activity against T. congolense.

Hyaluronidase and degranulation inhibitors from the edible roots of Oenanthe javanica including seric acids F and G that were obtained by heating.

Oenanthe javanica is a vegetable grown in East Asia and Australia in which the roots and aerial parts are boiled together to make certain traditional dishes. Nineteen compounds (1-19) were isolated from O. javanica roots and the chemical structures of 2 new norlignans were determined. The inhibitory effects of the compounds on hyaluronidase and degranulation in RBL-2H3 cells were evaluated to determine antiallergic and antiinflammation activities. Saponins (2-4) and the new norlignan seric acid G (12) were among the active compounds identified. Seric acid G (12), a methoxy derivative of seric acid F (11), was obtained as an interconverting mixture of 3:1 trans-cis isomers. Seric acids F and G (11, 12) were derived from seric acids C (10) and E, respectively, by decarboxylation and dehydration reactions that occurred during heating. It was confirmed by HPLC analysis that all eleven of the O. javanica cultivars contained seric acid C (10).

Constituents of the Fruiting Body of Poisonous Mushroom Omphalotus japonicus.

Six new sesquiterpenes, tsukiyols A-C, neoilludin C, and 4-O-methylneoilludins A and B, were isolated from the fruiting body of Omphalotus japonicus (Kawam.) Kirchm. & O. K. Mill. Additionally, six known compounds, illudin S, neoilludins A-B, 5-hydroxydichomitol, ergosterolperoxide, and 3ß,5α,9α-trihydroxyergosta-7,22-diene-6-one, were also obtained. Their chemical structures were determined with MS, IR, and NMR spectra and the absolute configurations of neoilludins A-C, 4-O-methylneoilludins A, and B were determined with electronic circular dichroism (ECD). Illudin S and 3ß,5α,9α-trihydroxyergosta-7,22-diene-6-one showed cytotoxicity against human acute promyelocytic leukemia HL60 cells. Illudin S, 4-O-methylneoilludin A, B, and tsukiyol C showed growth-restoring activity against mutant yeast via Ca2+-signal transduction.

Biological Properties, Bioactive Constituents, and Pharmacokinetics of Some Capsicum spp. and Capsaicinoids.

Pepper originated from the Capsicum genus, which is recognized as one of the most predominant and globally distributed genera of the Solanaceae family. It is a diverse genus, consisting of more than 31 different species including five domesticated species, Capsicum baccatum, C. annuum, C. pubescen, C. frutescens, and C. chinense. Pepper is the most widely used spice in the world and is highly valued due to its pungency and unique flavor. Pepper is a good source of provitamin A; vitamins E and C; carotenoids; and phenolic compounds such as capsaicinoids, luteolin, and quercetin. All of these compounds are associated with their antioxidant as well as other biological activities. Interestingly, Capsicum fruits have been used as food additives in the treatment of toothache, parasitic infections, coughs, wound healing, sore throat, and rheumatism. Moreover, it possesses antimicrobial, antiseptic, anticancer, counterirritant, appetite stimulator, antioxidant, and immunomodulator activities. Capsaicin and Capsicum creams are accessible in numerous ways and have been utilized in HIV-linked neuropathy and intractable pain.

Acylated Lignans Isolated from Brachanthemum gobicum and Their Trypanocidal Activity.

Eight isovaleryllignans (1-4 and 8-11), three isovalerylphenylpropanoids (5-7), three known lignans (12-14), and four known compounds were isolated from an extract of the aerial part of Brachanthemum gobicum. The structures of the isolated compounds were elucidated based on NMR and MS data analyses. The enantiomers of compounds 1-3, 5, 8, and 9 were isolated using chiral-phase HPLC, and the absolute configurations of 1a/1b-3a/3b, 5a/5b, 8a/8b, and 9a/9b were elucidated from their optical rotations and ECD spectra; the other lignans were assumed to be racemic or scalemic by chiral-phase HPLC analyses and optical rotation data. Some of the acylated lignans (racemic mixtures) (1-4, 8, 9, and 12-14) exhibited moderate inhibitory activities against Trypanosoma congolense, the causative agent of nagana disease in animals.

Inhibitory Effects of Phenylpropanoid Derivatives from Oenanthe javanica on Antigen-Stimulated Degranulation in RBL-2H3 Cells.

Two diacyldaucic acids (1 and 2), an α,ß-unsaturated γ-lactone-type lignan (3) and its derivatives (4-6), and 12 known compounds were isolated from a traditional East Asian vegetable, Oenanthe javanica. The absolute configuration of 1 was validated by obtaining (+)-osbeckic acid through acid hydrolysis. The absolute configurations of 3-5 were determined by comparing their experimental and computed ECD data. The conclusion was supported by applying the phenylglycine methyl ester method to 3. Compound 6 was obtained as an interconverting mixture of isomers in a 3:1 trans- cis ratio. Several water-soluble components (1, 3, and 6) showed concentration-dependent inhibitory effects on antigen-stimulated degranulation in RBL-2H3 cells without producing any direct cytotoxicity against RBL-2H3 or HeLa cells.

[Complete Remission of Advanced Gastric Cancer with Tumor Embolism in the Right Gastric Vein Treated with Radical Resection after Chemotherapy].

A 74-year-old man presented to our hospital with the chief complaint of epigastric pain; upper gastrointestinal endoscopy revealed a 7-cm-sized type 3 gastric cancer in the lesser curvature of the lower part of the stomach. Abdominal contrast computed tomography revealed a tumor embolus in the right gastric vein; the preoperative diagnosis was cT4a(SE) N3aH0P0M0, cStage ⅢC. Because the cancer could spread during surgical manipulation, performing a safe radical resection was difficult; therefore, we decided to initiate chemotherapy. The patient received 3 courses of trastuzumab plus CapeOX, which led to reduction of the primarylesion, peri-gastric lymph node, and right gastric vein tumor embolus. Partial remission was achieved after chemotherapy; therefore, distal gastrectomy, D2 lymph node dissection, and Roux-en-Y reconstruction were performed. Histopathological examination did not reveal viable tumor cells in the primarylesion, lymph nodes, or tumor embolus, and the histological effect was Grade 3. Currently, the patient is alive without relapse at 9 months post operation. Advanced gastric cancer accompanied with tumor embolism in the gastric vein is commonly observed in patients with liver metastasis and in those with severely progressed state of cancer; many of these patients have poor prognosis. Preoperative chemotherapymaybe effective in cases in which tumor embolism in the gastric vein is identified through preoperative diagnostic imaging.

[Pulmonary Pleomorphic Carcinoma Relapsed after Surgery Surviving Long-term by Chemotherapy and Nivolumab].

A 60'-year-old man was referred to our hospital because of nodular shadow found at mass screening. We diagnosed the tumor as non-small cell lung cancer by transbronchial biopsy. Chest computed tomography showed a tumor shadow of 3 cm in diameter with cavity. Right middle lobectomy was performed and the pathological diagnosis was pleomorphic carcinoma of the lung. The tumor recurrence was found at 10 months after surgery, and was treated with cisplatin, docetaxel plus bevacizumab for 6 cycles. A complete remission was achieved, but regrowth at 5 months after chemotherapy was noted. The patient was treated with nivolumab following carboplatin, gemcitabine plus bevacizumab 3 cycles. A good partial response is continuing 2 years and 5 months after confirming recurrence.

[Bilateral Metastatic Lung Tumor with Different Primary Organs].

A 72-year-old woman with a history of surgery for left breast cancer was found to have sigmoid colon cancer and solitary pulmonary tumor of left upper lobe. We diagnosed adenocarcinoma of the unknown origin by a transbronchial biopsy. We performed left upper segmentectomy and sigmoidectomy. Left pulmonary tumor was diagnosed metastatic lung tumor from breast cancer. A right pulmonary tumor was confirmed by chest computed tomography(CT) after sigmoidectomy. It was also considered to be metastasis from breast cancer and treated with vinorelbine ditartrate. Since no effect was observed by chemotherapy, tumor was surgically removed by wedge resection. Right pulmonary tumor was pathologically diagnosed as metastasis from sigmoid colon cancer. In suspicious case of pulmonary metastases from double cancer, the possibility of different lesions from different primary site should be kept in mind.

Flavonoid and Galloyl Glycosides Isolated from Saxifraga spinulosa and Their Antioxidative and Inhibitory Activities against Species That Cause Piroplasmosis.

Eight new flavonoid-based 3'-O-ß-d-glucopyranosides (1-8) and three new galloyl glucosides (9, 11, 12), were isolated from the aerial parts of Saxifraga spinulosa, along with 25 known compounds. The structures of the new compounds were elucidated by spectroscopic methods. Most of the isolated compounds exhibited potent DPPH radical-scavenging activities. Further, their inhibitory activities were evaluated against Babesia bovis, Babesia bigemina, Babesia caballi, and Theileria equi, protozoan parasites that cause piroplasmosis in livestock. The results indicated that several of these compounds showed growth-inhibitory effects on such organisms that cause piroplasmosis.

Antioxidant Flavonols and Phenolic Compounds from Atraphaxis frutescens and Their Inhibitory Activities against Insect Phenoloxidase and Mushroom Tyrosinase.

Chemical investigation of the aerial parts of Atraphaxis frutescens resulted in the isolation of five 7-methoxyflavonols with pyrogallol B-ring moieties (1-5), a fisetinidol glucoside (13), and a benzyl glycoside (18), together with 26 known compounds including flavonoids, phenylpropanoid amides, anthraquinone glycosides, lignans, and a benzyl derivative. The principal chemical structural feature of the isolated compounds was either a pyrogallol or catechol B-ring moiety, and they showed potent 1,1-diphenyl-2-picrylhydrazyl radical scavenging activities. To assess the effects of these antioxidants on biological enzymes, their inhibitory effects against an insect phenoloxidase and a mushroom tyrosinase were evaluated. This study indicated that insect phenoloxidase was inhibited by phenylpropanoid amides and that mushroom tyrosinase was inhibited by the characteristic 7-methoxyflavonol 3-O-rhamnopyranosides.

Trypanocidal Activity of 2,5-Diphenyloxazoles Isolated from the Roots of Oxytropis lanata.

Eleven 2,5-diphenyloxazole derivatives (1-11), together with six known isoflavonoid derivatives, were isolated from the roots of Oxytropis lanata. The 2,5-diphenyloxazole (1) obtained proved to be identical to a standard sample used as a scintillator and liquid laser dye. The other oxazole derivatives isolated were found to have one to four hydroxy and/or O-methyl groups in their phenyl rings. Seven of the oxazole derivatives obtained are new (3-9). The inhibitory activity of the isolated compounds was evaluated against Trypanosoma congolense, the causative agent of African trypanosomosis in animals. Oxazoles with di- and trihydroxy groups showed trypanocidal activity, and 2-(2',3'-dihydroxyphenyl)-5-(2″-hydroxyphenyl)oxazole (4) exhibited the most potent inhibitory activity (IC50 1.0 µM).

An antibacterial ortho-quinone diterpenoid and its derivatives from Caryopteris mongolica.

To identify antibacterial components in traditional Mongolian medicinal plant Caryopteris mongolica, an ortho-quinone abietane caryopteron A (1) and three its derivatives caryopteron B-D (2-4) were isolated from the roots of the plant together with three known abietanes demethylcryptojaponol (5), 6α-hydroxydemethyl cryptojaponol (6), and 14-deoxycoleon U (7). The chemical structures of these abietane derivatives were elucidated on the basis of spectroscopic data. Compounds 1-4 had C-13 methylcyclopropane substructures, and 2-4 had a hexanedioic anhydride ring C instead of ortho-quinone in 1. The stereochemistry of these compound was assumed from NOE spectra and ECD Cotton effects. Compounds 1 and 5-7 showed antibacterial activities against the Gram-positive bacteria Staphylococcus aureus, Staphylococcus epidermidis, Enterococcus faecalis, and Micrococcus luteus, being 1 the more potent.

Ultrastructural analysis of an enterolith composed of deoxycholic acid.

A 67-year-old Japanese man underwent enterotomy because of enterolith ileus. Component analysis by infrared spectroscopy revealed that the enterolith was composed of a high concentration of deoxycholic acid. We further analyzed and compared the ultrastructure of the enterolith and a commercially available powdered form of deoxycholic acid by means of scanning electron microscopy and energy dispersive X-ray spectroscopy. Energy dispersive X-ray spectroscopy analysis revealed that the ratios of carbon and oxygen in the enterolith were equal to those in the deoxycholic acid powder. Scanning electron microscopy analysis showed rectangular prism-shaped particles on the surface of the enterolith. This structure was similar to that of the deoxycholic acid powder. The surgically removed enterolith had a twisted and coiled appearance. Possible mechanisms underlying the formation of this unique form are discussed.

Chemical constituents of aerial parts and roots of Pycnanthemum flexuosum.

An extract of whole plants of Pycnanthemum flexuosum showed an inhibitory effect on hyaluronidase activity. From an 80% acetone extract of aerial parts, 3-[(3E)-4-phenylbut-3-enoylamino]propionic acid, 3-O-ß-D-glucuronopyranosyl-echinocystic acid 28-O-ß-D-xylopyranosyl-(1→3)-[3,4-diacetyl-ß-D-xylopyranosyl-(1→4)]-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl ester, vanillic acid 1-O-[(5-O-syringoyl)-ß-D-apiofuranosyl]-(1→2)-ß-D-glucopyranoside, and (4S,5R)-4-hydroxy-5-phenyl-tetrahydrofuran-2-one were isolated together with 30 known compounds. Six known compounds were isolated from an 80% acetone extract of roots, and eritrichin was revealed as a hyaluronidase inhibitor in P. flexuosum.

Evaluation of the antiplasmodial efficacy of synthetic 2,5-diphenyloxazole analogs of compounds naturally derived from Oxytropis lanata.

The persistent prevalence and dissemination of drug-resistant malaria parasites continue to challenge the progress of malaria eradication efforts. As a result, there is an urgent need to search for and develop innovative therapies. In this study, we screened synthetic 2,5-diphenyloxazole analogs from Oxytropis lanata. Among 48 compounds, 14 potently inhibited the proliferation of P. falciparum strains 3D7 (chloroquine-sensitive) and K1 (multidrug-resistant) in vitro, exhibited IC50 values from 3.38 to 12.65 µM and 1.27-6.19 µM, respectively, and were toxic to human foreskin fibroblasts at 39.53-336.35 µM. Notably, Compounds 31 (2-(2',3'-dimethoxyphenyl)-5-(2″-hydroxyphenyl)oxazole) and 32 (2-(2',3'-dimethoxyphenyl)-5-(2″-benzyloxyphenyl)oxazole) exhibited the highest selectivity indices (SIs) against both P. falciparum strains (3D7/K1), with values > 40.20/>126.58 and > 41.27/> 59.06, respectively. In the IC50 speed and stage-specific assays, Compounds 31 and 32 showed slow action, along with distinct effects on the ring and trophozoite stages. Microscopy observations further revealed that both compounds impact the development and delay the progression of the trophozoite and schizont stages in P. falciparum 3D7, especially at concentrations 100 times their IC50 values. In a 72-h in vitro exposure experiment at their respective IC80 in P. falciparum 3D7, significant alterations in parasitemia levels were observed compared to the untreated group. In Compound 31-treated cultures, parasites shrank and were unable to reinvade red blood cells (RBCs) during an extended 144-h incubation period, even after compound removal from the culture. In vivo assessments were conducted on P. yoelii 17XNL-infected mice treated with Compounds 31 and 32 at 20 mg/kg administered once daily for ten days. The treated groups showed statistically significant lower peaks of parasitemia (Compound 31-treated: trial 1 12.7%, trial 2 15.8%; Compound 32-treated: trial 1 12.7%, trial 2 14.0%) compared to the untreated group (trial 1 21.7%, trial 2 28.3%). These results emphasize the potential of further developing 2,5-diphenyloxazoles as promising antimalarial agents.

Chemical constituents of five Saxifraga species and their virucidal activities.

The chemical constituents of Saxifraga stolonifera, S. fortunei, S. nipponica, S. cortusifolia, and S. rebunshirensis were investigated for structure and virucidal activity. In addition to the Saxifraga species-derived tannins, 30 compounds (1-30) were isolated from the five species. 5-Hydroxy-4-methoxy-3-O-(6-O-caffeoyl)-ß-D-glucopyranosyl benzoic acid (1) and kaempferol 3-O-ß-d-xylopyranosyl-(1 â†’ 2)-ß-D-xylopyranoside (2) were identified as undescribed compounds. Although 1 was isolated as the (E)-isomer of its caffeoyl moiety, under light it became over time a mixture of the (Z)-isomer (1a) and (E)-isomer (1). Kaempferol 3-O-ß-d-xylopyranosyl-(1 â†’ 2)-ß-D-glucopyranoside (3) was an analog of 2 and a known compound, whose NMR assignment was reconsidered and described. 6-Isopropyl-5,5-dimethyldihydropyrimidine-2,4(1H,3H)-dione (30) was expected to be a racemic mixture based on its optical rotation and X-ray crystallography data. The virucidal activities of the isolated compounds (1-30) against influenza A virus, severe acute respiratory syndrome coronavirus 2, feline calicivirus, and murine norovirus were evaluated to identify the presence of compounds other than the Saxifraga species-derived tannins, which exhibited virucidal activities. Although the isolated compound activities were relatively weak compared to those of Saxifraga species-derived tannins, the potential virucidal activity of the compounds with galloyl groups was confirmed.