In Vitro Anticancer Activity of Mucoadhesive Oral Films Loaded with Usnea barbata (L.) F. H. Wigg Dry Acetone Extract, with Potential Applications in Oral Squamous Cell Carcinoma Complementary Therapy

Oral squamous cell carcinoma (OSCC) is the most frequent oral malignancy, with a high death rate and an inadequate response to conventional chemotherapeutic drugs. Medical research explores plant extracts’ properties to obtain potential nanomaterial-based anticancer drugs. The present study aims to formulate, develop, and characterize mucoadhesive oral films loaded with Usnea barbata (L.) dry acetone extract (F-UBA) and to investigate their anticancer potential for possible use in oral cancer therapy. U. barbata dry acetone extract (UBA) was solubilized in ethanol: isopropanol mixture and loaded in a formulation containing hydroxypropyl methylcellulose (HPMC) K100 and polyethylene glycol 400 (PEG 400). The UBA influence on the F-UBA pharmaceutical characteristics was evidenced compared with the references, i.e., mucoadhesive oral films containing suitable excipients but no active ingredient loaded. Both films were subjected to a complex analysis using standard methods to evaluate their suitability for topical administration on the oral mucosa. Physico-chemical and structural characterization was achieved by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and atomic force microscopy (AFM). Pharmacotechnical evaluation (consisting of the measurement of specific parameters: weight uniformity, thickness, folding endurance, tensile strength, elongation, moisture content, pH, disintegration time, swelling rate, and ex vivo mucoadhesion time) proved that F-UBAs are suitable for oral mucosal administration. The brine shrimp lethality (BSL) assay was the F-UBA cytotoxicity prescreen. Cellular oxidative stress, caspase 3/7 activity, nuclear condensation, lysosomal activity, and DNA synthesis induced by F-UBA in blood cell cultures and oral epithelial squamous cell carcinoma (CLS-354) cell line were investigated through complex flow cytometry analyses. Moreover, F-UBA influence on both cell type division and proliferation was determined. Finally, using the resazurin-based 96-well plate microdilution method, the F-UBA antimicrobial potential was explored against Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27353, Candida albicans ATCC 10231, and Candida parapsilosis ATCC 22019. The results revealed that each UBA-loaded film contains 175 µg dry extract with a usnic acid (UA) content of 42.32 µg. F-UBAs are very thin (0.060 ± 0.002 mm), report a neutral pH (7.01 ± 0.01), a disintegration time of 146 ± 5.09 s, and an ex vivo mucoadhesion time of 85 ± 2.33 min, and they show a swelling ratio after 6 h of 211 ± 4.31%. They are suitable for topical administration on the oral mucosa. Like UA, they act on CLS-354 tumor cells, considerably increasing cellular oxidative stress, nuclear condensation, and autophagy and inducing cell cycle arrest in G0/G1. The F-UBAs inhibited the bacterial and fungal strains in a dose-dependent manner; they showed similar effects on both Candida sp. and higher inhibitory activity against P. aeruginosa than S. aureus. All these properties lead to considering the UBA-loaded mucoadhesive oral films suitable for potential application as a complementary therapy in OSCC.

Evaluation of Usnea barbata (L.) Weber ex F.H. Wigg Extract in Canola Oil Loaded in Bioadhesive Oral Films for Potential Applications in Oral Cavity Infections and Malignancy

Usnea lichens are known for their beneficial pharmacological effects with potential applications in oral medicine. This study aims to investigate the extract of Usnea barbata (L.) Weber ex F.H. Wigg from the Călimani Mountains in canola oil as an oral pharmaceutical formulation. In the present work, bioadhesive oral films (F-UBO) with U. barbata extract in canola oil (UBO) were formulated, characterized, and evaluated, evidencing their pharmacological potential. The UBO-loaded films were analyzed using standard methods regarding physicochemical and pharmacotechnical characteristics to verify their suitability for topical administration on the oral mucosa. F-UBO suitability confirmation allowed for the investigation of antimicrobial and anticancer potential. The antimicrobial properties against Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27353, Candida albicans ATCC 10231, and Candida parapsilosis ATCC 22019 were evaluated by a resazurin-based 96-well plate microdilution method. The brine shrimp lethality assay (BSL assay) was the animal model cytotoxicity prescreen, followed by flow cytometry analyses on normal blood cells and oral epithelial squamous cell carcinoma CLS-354 cell line, determining cellular apoptosis, caspase-3/7 activity, nuclear condensation and lysosomal activity, oxidative stress, cell cycle, and cell proliferation. The results indicate that a UBO-loaded bioadhesive film’s weight is 63 ± 1.79 mg. It contains 315 µg UBO, has a pH = 6.97 ± 0.01, a disintegration time of 124 ± 3.67 s, and a bioadhesion time of 86 ± 4.12 min, being suitable for topical administration on the oral mucosa. F-UBO showed moderate dose-dependent inhibitory effects on the growth of both bacterial and fungal strains. Moreover, in CLS-354 tumor cells, F-UBO increased oxidative stress, diminished DNA synthesis, and induced cell cycle arrest in G0/G1. All these properties led to considering UBO-loaded bioadhesive oral films as a suitable phytotherapeutic formulation with potential application in oral infections and neoplasia.

Antioxidant, Cytotoxic, and Rheological Properties of Canola Oil Extract of Usnea barbata (L.) Weber ex F.H. Wigg from Călimani Mountains, Romania

Usnea genus (Parmeliaceae, lichenized Ascomycetes) is a potent phytomedicine, due to phenolic secondary metabolites, with various pharmacological effects. Therefore, our study aimed to explore the antioxidant, cytotoxic, and rheological properties of Usnea barbata (L.) Weber ex F.H. Wigg (U. barbata) extract in canola oil (UBO) compared to cold-pressed canola seed oil (CNO), as a green solvent used for lichen extraction, which has phytoconstituents. The antiradical activity (AA) of UBO and CNO was investigated using UV-Vis spectrophotometry. Their cytotoxicity was examined in vivo through a brine shrimp lethality (BSL) test after Artemia salina (A. salina) larvae exposure for 6 h to previously emulsified UBO and CNO. The rheological properties of both oil samples (flow behavior, thixotropy, and temperature-dependent viscosity variation) were comparatively analyzed. The obtained results showed that UBO (IC₅₀ = 0.942 ± 0.004 mg/mL) had a higher 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity than CNO (IC₅₀ = 1.361 ± 0.008 mg/mL). Both UBO and CNO emulsions induced different and progressive morphological changes to A. salina larvae, incompatible with their survival; UBO cytotoxicity was higher than that of CNO. Finally, in the temperature range of 32-37 °C, the UBO and CNO viscosity and viscoelastic behavior indicated a clear weakening of the intermolecular bond when temperature increases, leading to a more liquid state, appropriate for possible pharmaceutical formulations. All quantified parameters were highly intercorrelated. Moreover, their significant correlation with trace/heavy minerals and phenolic compounds can be observed. All data obtained also suggest a possible synergism between lichen secondary metabolites, minerals, and canola oil phytoconstituents.

Elemental Analysis and In Vitro Evaluation of Antibacterial and Antifungal Activities of Usnea barbata (L.) Weber ex F.H. Wigg from Călimani Mountains, Romania

This study aims to complete our research on Usnea barbata (L.) Weber ex F.H. Wigg (U. barbata) from the Călimani Mountains, Romania, with an elemental analysis and to explore its antibacterial and antifungal potential. Thus, we analyzed twenty-three metals (Ca, Fe, Mg, Mn, Zn, Al, Ag, Ba, Co, Cr, Cu, Li, Ni, Tl, V, Mo, Pd, Pt, Sb, As, Pb, Cd, and Hg) in dried U. barbata lichen (dUB) by inductively coupled plasma mass spectrometry (ICP-MS). For the second study, we performed dried lichen extraction with five different solvents (ethyl acetate, acetone, ethanol, methanol, and water), obtaining five U. barbata dry extracts (UBDE). Then, using an adapted disc diffusion method (DDM), we examined their antimicrobial activity against seven bacterial species-four Gram-positive (Staphylococcus aureus, Enterococcus casseliflavus, Streptococcus pyogenes, and Streptococcus pneumoniae) and three Gram-negative (Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa)-and two fungi species (Candida albicans and Candida parapsilosis). Usnic acid (UA) was used as a positive control. The ICP-MS data showed a considerable Ca content (979.766 µg/g), followed by, in decreasing order, Mg, Mn, Al, Fe, and Zn. Other elements had low levels: Ba, Cu, Pb, and Cr (3.782-1.002 µg/g); insignificant amounts (<1 µg/g) of Hg and V were also found in dUB. The trace elements Ag, As, Cd, Co, Li, Tl, Mo, Pd, Pt, and Sb were below detection limits (<0.1 µg/g). The DDM results-expressed as the size (mm) of the inhibition zone diameter (IZs)-proved that the water extract did not have any inhibitory activity on any pathogens (IZs = 0 mm). Gram-positive bacteria displayed the most significant susceptibility to all other UBDE, with Enterococcus casseliflavus showing the highest level (IZs = 20-22 mm). The most susceptible Gram-negative bacterium was Pseudomonas aeruginosa (IZs = 16-20 mm); the others were insensitive to all U. barbata dry extracts (IZs = 0 mm). The inhibitory activity of UBDE and UA on Candida albicans was slightly higher than on Candida parapsilosis.

Antioxidant and Cytotoxic Activities of Usnea barbata (L.) F.H. Wigg. Dry Extracts in Different Solvents

Lichens represent a significant source of antioxidants due to numerous metabolites that can reduce free radicals. Usnea barbata (L.) F.H. Wigg. has been recognized and used since ancient times for its therapeutic effects, some of which are based on its antioxidant properties. The present study aims to analyze the phytochemical profile and to evaluate the antioxidant and cytotoxic potential of this lichen species. Five dry extracts of U. barbata (UBDE) in different solvents (acetone, ethyl acetate, ethanol, methanol, water) were prepared by refluxing at Soxhlet to achieve these proposed objectives and to identify which solvent is the most effective for the extraction. The usnic acid content (UAC) was quantified by ultra-high performance liquid chromatography (UHPLC). The total polyphenols content (TPC) and tannins content (TC) were evaluated by spectrophotometry, and the total polysaccharides (PSC) were extracted by a gravimetric method. The 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) free radical method was used to assess the antioxidant activity (AA) and the Brine Shrimp Lethality (BSL) assay was the biotest for cytotoxic activity evaluation. The ethyl acetate extract had the highest usnic acid content, and acetone extract had the highest content of total polyphenols and tannins. The most significant antioxidant effect was reported to methanol extract, and all the extracts proved high cytotoxicity. The water extract has the lowest cytotoxicity because usnic acid is slightly soluble in this solvent, and it was not found at UHPLC analysis. All extracts recorded a moderate correlation between the content of usnic acid, polyphenols, tannins, and AA; furthermore, it has been observed that the cytotoxicity varies inversely with the antioxidant effect.

Evaluation of the Cytotoxic Activity of the Usnea barbata (L.) F. H. Wigg Dry Extract

The secondary metabolites of lichens have proven to be promising sources of anticancer drugs; one of the most important of these is usnic acid, which is a phenolic compound with dibenzofuran structure that is responsible for the numerous biological actions of lichens of genus Usnea. As a result, in this study, we related to this phenolic secondary metabolite. The aim of the present study is the evaluation of the cytotoxic activity of Usnea barbata (L.) F. H. Wigg dry acetone extract (UBE). In advance, the usnic acid content was determined in various extracts of Usnea barbata (L.) F. H. Wigg: the liquid extracts were found in water, ethanol, acetone, and the dry acetone extract; the highest usnic acid quantity was found in the dry acetone extract. First, the cytotoxic action of UBE was assessed using Brine Shrimp Lethality (BSL) test; a significant lethal effect was obtained after 24 h of treatment at high used concentrations of UBE, and it was quantified by the high mortality rate of the Artemia salina (L.) larvae. Secondly, in vitro cytotoxicity of UBE was evaluated on human tongue squamous cells carcinoma, using CAL 27 (ATCC® CRL-2095™) cell line. The most intense cytotoxic effect of UBE on CAL 27 cells was registered after 24 h; this response is directly proportional with the tested UBE concentrations. The obtained results have been reported regarding usnic acid content of UBE, and the data show that CAL 27 cells death was induced by apoptosis and high oxidative stress.

Studies on the Phytochemical Composition and Antioxidant Activity of a Prunus spinosa L. Aqueous Extract

The purpose of this study was to analyze the phenolic compounds and the antioxidant activity of the aqueous extract obtained from the fruit of Prunus spinosa L.. The aqueous extract of 10% concentration was obtained from the pulp of dried fruits, harvested from Tulcea county, Romania. The tannin content was 3.38g % and the total polyphenols 6.95g %. Based on the HPLC analysis, the identified polyphenolic acids were chlorogenic acid, caffeic acid and gallic acid and the concentrations in mg per 100g of fruit pulp powder were 15.174, 10.93 and 81.468, respectively. The 100 mg/mL aqueous extract had a high DPPH radical scavenger ability (87.30%) which correlated with the polyphenol content and supports the possibility of using rich bioactive aqueous extracts for oxidative stress related conditions.

Studies on Preparation and UHPLC Analysis of the Usnea Barbata (L) F.H.Wigg Dry acetone extract

In the category of medicinal plants with remarkable therapeutic properties, lichens are also included. An important representative of this group is the Usnea Adans. genus, with over 650 species spread throughout the globe. Representative species of this genus were also found in Romania, so the studies were conducted on Usnea barbata (L.) F.H.Wigg., harvested from the Calimani Mountains, Suceava County. The objectives of this research are: obtaining the dry extract of the Usneae lichen followed by the identification and determination of the usnic acid content by ultra-high performance liquid chromatography (UHPLC) method. Usnic acid content determined in dry extract of Usnea barbata (L.) F.H.Wigg. was significant, of 16.53 � 6.53% (mean � RSD), which supports the continuation of the research with the evaluation of biological effects (antibacterial, antioxidant and antitumoral).

Phytochemical Profile and Total Antioxidant Capacity of Sempervivum ruthenicum Koch Hydroethanolic Extract

The scope of this work is a phytochemical analysis and antioxidant activity assay of a Sempervivum ruthenicum Koch hydroethanolic extract. The hydroethanolic extract was prepared from the dried leaves of the plant by maceration in a water and methanol mixture (50:50 v/v). The total phenolic content of the extract was calculated to be 3.0501�0.0272 mg/mL and the total flavonoid content was determined in a concentration of 3.113�0.0394 mg/mL. The HPLC-DAD analysis revealed phenolic acids and flavonoids, which were quantified. The most prevalent phenolic acids in the extracts were gallic and ellagic acids, with concentrations of 1.2443�0.0475 mg/mL, respectively 0.6339�0.0026 mg/mL. The heteroside astragalin was present in high concentration of 1.1934�0.0754 mg/mL. The DPPH free radical scavenging assay revealed the EC50 value of the extract to be 2.5788�0.003 mg/mL. These results suggest a good scavenging ability of the extract, which is due to the abundance of polyphenolic compounds. The antioxidant activity of the extract demonstrates a high scavenging ability at low doses. Sempervivum ruthenicum Koch shows a promising phytochemical profile that suggests it�s use in pathological conditions that involve high oxidative stress.

Antimicrobial Effect of 940 nm Diode Laser based on Photolysis of Hydrogen Peroxide in the Treatment of Periodontal Disease

Moderate and severe periodontitis represents a challenge in the non-surgical periodontal therapy. Due to the lack of evidence regarding the antimicrobial effectiveness of 940 nm diode laser in periodontal treatment, this study aimed to evaluate the antimicrobial effect of hydrogen peroxide (H2O2) photolysis performed with 940 nm diode laser in the treatment of moderate and severe periodontitis. Twenty-five patients with 100 teeth were selected for this pilot study. The test teeth were randomly assigned to one of the four treatment groups: Group 1: scaling and root planning (SRP) (control group); and the following experimental groups: Group 2: H2O2; Group 3: 940 nm diode laser therapy; Group 4: 940 nm diode laser therapy and H2O2. Clinical examinations, like probing depth (PD), clinical attachment level (CAL) and bleeding on probing (BOP) were performed before and after the treatment. The microbiological evaluation, effectuated before and after the treatment, included nine periodontal bacteria species and investigated by means of real-time PCR assay. The clinical and bacterial differences in the tested groups, was assessed between control group and the other three experimental groups, as well as between the experimental groups. The total bacteria load was reduced for all four studied groups. Group 4 (diode laser + H2O2) showed significant bacterial reduction of the major periodontal bacteria like Pg., Tf., Td., Pi., Pm., Fn (p[0.001) than the other 3 groups (p]0.001). Also the periodontal clinical parameters, like PD, CAL and BOP showed a significant reduction after the photolysis of H2O2 with the 940 nm diode laser (p[0.001). Differences between tested groups showed a significant beneficial results in regard to Group 4.It is suggested that the photoactivation of H2O2 with the 940 nm diode laser can be used successfully in adjunctive to the non-surgical periodontal treatment as a bactericidal tool.

Investigations on the photochromic properties of 2,6-bis(5-bromo-2-hydroxybenzylidene)cyclohexanone

The network of chemical reactions of 2,6-bis(5-bromo-2-hydroxybenzylidene)cyclohexanone (BHBC) when subjected to light and different pH values has been investigated. The pH dependent species involved in the chemical network have been identified and characterized by NMR and UV-VIS spectroscopy. Direct pH jumps were carried out by adding a strong acid to equilibrated solutions of trans-chalcone (Ct) forming the flavylium cation which was stable only under extremely acidic conditions (pH < 0.5). The single crystal X-ray study and NMR analysis has confirmed the structure of the new flavylium cation. In the case of a reverse pH jump, the Ct species interconverted instantaneously into deprotonated trans-chalcone (Ct^2-) around pH 12. A new colorless compound 3,11-dibromo-7,8-dihydro-6H-chromeno[3,2-d]xanthene (B-B) isolated from the equilibrated solution of trans-chalcone species in methanol after long periods of time (100 h) under dark conditions has been isolated and fully characterized by NMR and X-ray diffraction. The rate of the reaction increased when the solution of trans-chalcone was exposed to light and the total conversion of Ct into the spiropyran-like compound (B-B) was achieved in about 30 minutes. The B-B form was stable under neutral and basic conditions, while at low pH values it converts into a cationic AH⁺ form.

Copper(II) Complex Compounds with Mixed Hydrazone Ligands

Three Cu(II) complex compounds with mixed hydrazone ligands have been prepared and characterized in view of their potential biological activity. The complex compounds have the formulas: [Cu(HLa)(Lc)Br], [CuLaLc] and [CuLbLc] . Na, where HLa = 4-dimethylamino benzaldehyde-2-benzothiazolyl hydrazone, H2Lb = 2-hydroxybenzaldehyde-2-benzothiazolyl hydrazone and HLc = 2-hydroxy-1-naphthyliden-N,N-dimethyl hydrazone. The complexes have been characterized by elemental and thermogravimetrical analysis, infrared, electronic and EPR spectra. EPR spectral studies of the complexes gave axial symmetry, with the ground state. The bonding parameters calculated from the electronic and EPR spectra indicate strong in-plane p-bonding for all the complexes. Investigations on antibacterial and antifungal activities show that the complexes are more active than the free ligands against various Gram positive, Gram negative bacteria and fungi.

[Hereditary pancreatitis]

We present the cases of three brothers (a woman and two men) with recurrent attacks of necrotic acute pancreatitis that were treated in our clinic. Two of them have diabetes mellitus controlled through insulin treatment. All patients have presented the first episode of acute pancreatitis around age of 35. We have observed a high level of serum triglyceride at admission, without evidence of lipid disorder. In addition we couldn't identify other causes of these episodes of acute pancreatitis (biliary stones, alcohol, trauma, drugs, lipid disorders). During the last year two members of this family presented recurrent attacks of abdominal pain without any biochemical or imaging signs of acute pancreatitis.

[Gastric stromal tumors--Clinical and histopathological analysis of four cases]

BACKGROUND

The aim of this study is to present our experience concerning a rare form of gastric tumor--gastrointestinal stromal tumor (GIST).

METHODOLOGY

We reviewed data of four patients with gastric stromal tumors, which have been admitted in our department from 1998-2002.

RESULTS

There were two females and two males with age of 75, 70, 65 and 63 years old. The average duration of symptoms until hospital admission was 7 days. During surgery we discovered proximal gastric tumors with 4, 5, 10 and 20 cm in largest diameter. We performed excision of the whole tumor with a security limit of 2 cm or gastric resection (one case), without limphadenectomy. One patient developed an anastomotic fistula with a good evolution under conservative treatment. All patients left the hospital in a good condition. Histopathological and immunohistochemical study diagnosed gastric stromal tumors by identifying the CD 117 maker. Postoperatively neither one of our patients received chemotherapy or radiotherapy. One female and one male patient died of peritoneal metastasis at nine months and respectively two years after operation. The other two patients are in a good condition up to date, without metastasis, one and respectively three years after surgical treatment. CONCLUSIOUS: Correct diagnosis, complete tumor resection and surveillance are essential steps in management of gastric stromal tumors.