Silver secnidazole nano-hybrid emulsion-based probiotics as a novel antifungal formula against multidrug-resistant vaginal pathogens

This study presents a novel approach to manage vaginal infections due to Candidiasis, utilizing a novel silver secnidazole nano-hybrid emulsion (Ag-Secn-NHE)-based probiotics and free Ag-Secn-NHE. Ag-Secn-NHE was prepared by simple homogenization‒ultrasonication technique and validated by using a ultraviolet‒visible scan, dynamic light scattering, transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy, and zeta potential. Saccharomyces cerevisiae (RCMB 002Y001) is the most effective probiotic-producing organism that demonstrates significant effects when combined with Ag-Secn-NHE. Ag-Secn-NHE-based probiotics showed significant antifungal effect compared to free Ag-Secn-NHE, silver nitrate, silver nanoparticles, secnidazole, secnidazole nanoemulsion, and commercial vaginal wash against multidrug-resistant vaginal pathogens. The highest inhibitory effect was achieved with Ag-Secn-NHE-based probiotic against Candida auris, Candida albicans, and Cryptococcus neoformans with minimal inhibitory concentration (MIC) 0.625 ± 0.002, 0.00625:1.25 ± 0.012 and 0.00625:1.25 ± 0.032 mg/mL, respectively, in comparison with Ag-Secn-NHE that show MIC at 0.00625:1.25 ± 0.612, 0.0125:2.5 ± 0.812, and 0.0125:2.5 ± 0.112 mg/mL (Ag:Secn). Ag-Secn-NHE-based- probiotic show minimum fungicidal concentration (MFC) at range from 2.5 to 20 mg/mL, wherever free Ag-Secn-NHE show MFC range from 5 to >20 mg/mL. Additionally, Ag-Secn-NHE-based probiotics have 75% inhibition of biofilm formation against C. auris and 60% inhibition of biofilm formation against both Cryptococcus neoformans and C. albicans in comparison with free Ag-Secn-NHE. Time-kill curves showed that the antifungal effect of Ag-Secn-NHE-based probiotics was fungistatic at 2MIC value after 4 h and after 16 h for Ag-Secn-NHE. TEM photographs showed that C. auris cells treated with Ag-Secn-NHE-based probiotic formula revealed severe deformations and distored ultrastructural changes. furthermore, results indicated that the Gamma radiation up to 15 kGy increases production of Ag-Secn-NHE in comparison with non-irradiated one.

Chitosan-based sponges containing clotrimazole for the topical management of vulvovaginal candidiasis

Vulvovaginal candidiasis (VVC) persists as a worrying women's healthcare issue, often relying on suboptimal therapeutics. Novel intravaginal dosage forms focusing on improving patient acceptability and featuring improved biopharmaceutical properties could be interesting alternatives to available antifungal products. Different formulations of sponges based on chitosan (Ch), with or without crosslinking and co-formulated with poly(N-vinylcaprolactam) (PNVCL), were produced for the topical administration of clotrimazole (CTZ) and further tested for physicochemical properties, drug release, cytotoxicity and antifungal activity. Results showed that high amounts of CTZ (roughly 30-50 %) could be incorporated into sponges obtained by using a simple freeze-drying methodology. Cross-linking of Ch with ammonia affected the morphology and mechanical features of sponges and shifted the release profile from sustained (around 20 % and 60 % drug released after 4 h and 24 h, respectively) to fast-releasing (over 90 % at 4 h). The combination of PNVCL with non-crosslinked Ch also allowed tuning drug release, namely by increasing the initial amount of CTZ released in simulated vaginal fluid (roughly 40 % after 4 h), as compared to sponges featuring only non-crosslinked Ch. All formulations displayed low toxicity to cell lines derived from the female genital tract, with viability values kept above 70 % after 24 h incubation with sponge extracts. These also allowed maintaining the rapid onset of the antifungal effects of CTZ at minimum inhibitory concentrations ranging from 0.5 to 16 μg/mL for a panel of six different Candida spp. strains. Overall, proposed sponge formulations appear to be promising alternatives for the safe and effective management of VVC.

Development and characterization of amphotericin B nanoemulsion-loaded mucoadhesive gel for treatment of vulvovaginal candidiasis

Despite being recognized as the "gold standard" for treating azole-resistant vulvovaginal candidiasis, amphotericin B (AmB), an amphoteric molecule, has not been widely used due to serious issues with solubility and permeability. In light of the aforementioned, the objective of the present study was to increase AmB's therapeutic efficacy by formulating it into an o/w nanoemulsion (AmB-NE) system. Furthermore, to facilitate AmB-NE's retention within the vaginal cavity, it was loaded into a mixture of Carbopol® 974P and Aloe vera-based gel (CA gel). Briefly, in the present study, a kinetically stable batch of formulated AmB-NE having a globule size of 76.52 ± 3.11 nm, PDI of 0.342 ± 0.032, and zeta potential of -22.32 ± 0.88 mV was incorporated into the CA gel base. This AmB-NE loaded gel (AmB-NE gel) exhibited a non-Fickian/anomalous diffusion from the hydrophilic matrix. The texture analysis of AmB-NE gel revealed that the prepared gel was a non-drip, soft, easy to spread, and sufficiently cohesive gel that could reside in the vaginal cavity, which was confirmed by our ex-vivo retention test, which revealed that AmB-NE loaded gel could stay in the vaginal cavity for approximately 11 h. Ex-vivo skin permeation studies revealed that AmB-NE is 4.26 times more permeable than AmB-coarse gel, implying that AmB-NE facilitates AmB entry into the vaginal epithelial layers. Furthermore, in-vivo vaginal lavage studies revealed that AmB-NE gel permeated 7.03-fold more than AmB-coarse gel. Prepared AmB-NE gel was stable in refrigerated condition and showed no histopathological toxicity. Thus, the present study suggests that AmB-NE gel could eliminate the existing problem of AmB and that it could serve as an alternative option to treat vulvovaginal candidiasis.

Nanomedicines for the topical treatment of vulvovaginal infections: Addressing the challenges of antimicrobial resistance

Recent years have, surprisingly, witnessed an increase in incidence of sexually transmitted infections (STIs). At the same time, antimicrobial therapy came under the threat of ever rising antimicrobial resistance (AMR), resulting in STIs with extremely limited therapy options. In this review, we addressed the challenges of treating vaginal infections in an era of AMR. We focused on published work regarding nanomedicine destined for localized treatment of vaginal infections. Localized therapy offers numerous advantages such as assuring high drug concentration at the infection site, limiting systemic drug exposure that can lead to faster development of AMR reduction in the systemic side effects and potentially safe therapy in pregnancy. We provided a state-of-the-art overview of nanoformulations proposed to topically treat STIs, emphasizing the challenges and advantages of each type of nanocarriers, as well as issues of potential toxicity.

Women-specific routes of administration for drugs: A critical overview

The woman's body presents a number of unique anatomical features that can constitute valuable routes for the administration of drugs, either for local or systemic action. These are associated with genitalia (vaginal, endocervical, intrauterine, intrafallopian and intraovarian routes), changes occurring during pregnancy (extra-amniotic, intra-amniotic and intraplacental routes) and the female breast (breast intraductal route). While the vaginal administration of drug products is common, other routes have limited clinical application and are fairly unknown even for scientists involved in drug delivery science. Understanding the possibilities and limitations of women-specific routes is of key importance for the development of new preventative, diagnostic and therapeutic strategies that will ultimately contribute to the advancement of women's health. This article provides an overview on women-specific routes for the administration of drugs, focusing on aspects such as biological features pertaining to drug delivery, relevance in current clinical practice, available drug dosage forms/delivery systems and administration techniques, as well as recent trends in the field.

Clotrimazole-loaded N-(2-hydroxy)-propyl-3-trimethylammonium, O-palmitoyl chitosan nanoparticles for topical treatment of vulvovaginal candidiasis

Vulvovaginal candidiasis (VVC) represents a considerable health burden for women. Despite the availability of a significant array of antifungal drugs and topical products, the management of the infection is not always effective, and new approaches are needed. Here, we explored cationic N-(2-hydroxy)-propyl-3-trimethylammonium, O-palmitoyl chitosan nanoparticles (NPs) as carriers of clotrimazole (CLT) for the topical treatment of VVC. CLT-NPs with approximately 280 nm in diameter were obtained by self-assembly in water and subsequent stabilization by ionic crosslinking with tripolyphosphate. The nanosystem featured pH-independent sustained drug release up to 24 h, which affected both in vitro anti-Candida activity and cytotoxicity. The CLT-loaded nanostructured platform yielded favorable selectivity index values for a panel of standard strains and clinical isolates of Candida spp. and female genital tract cell lines (HEC-1-A, Ca Ski and HeLa), as compared to the free drug. CLT-NPs also improved in vitro drug permeability across HEC-1-A and Ca Ski cell monolayers, thus suggesting that the nanocarrier may provide higher mucosal tissue levels of the active compound. Overall, data support that CLT-NPs may be a valuable asset for the topical treatment of VVC. STATEMENT OF SIGNIFICANCE: Topical azoles such as clotrimazole (CLT) are first line antifungal drugs for the management of vulvovaginal candidiasis (VVC), but their action may be limited by issues such as toxicity and poor capacity to penetrate the genital mucosa. Herein, we report on the ability of a new cationic N-(2‑hydroxy)-propyl-3-trimethylammonium, O-dipalmitoyl chitosan derivative (DPCat35) to yield tripolyphosphate-reinforced micelle-like nanostructures that are suitable carriers for CLT. In particular, these nanosystems were able to improve the in vitro selectivity index of the drug and to provide enhanced epithelial drug permeability when tested in cell monolayer models. These data support that CLT-loaded DPCat35 nanoparticles feature favorable properties for the development of new nanomedicines for the topical management of VVC.

Vulvovaginal Candidosis (Excluding Mucocutaneous Candidosis): Guideline of the German (DGGG), Austrian (OEGGG) and Swiss (SGGG) Society of Gynecology and Obstetrics (S2k-Level, AWMF Registry Number 015/072, September 2020)

Aim The aim of this official guideline, published and coordinated by the German (DGGG), Austrian (OEGGG) and Swiss (SGGG) Societies of Gynecology and Obstetrics in collaboration with the DMykG, DDG and AGII societies, was to provide consensus-based recommendations obtained by evaluating the relevant literature for the diagnosis, treatment and management of women with vulvovaginal candidosis. Methods This S2k guideline represents the structured consensus of a representative panel of experts with a range of different professional backgrounds commissioned by the Guideline Committee of the above-mentioned societies. Recommendations This guideline gives recommendations for the diagnosis, management, counseling, prophylaxis and screening of vulvovaginal candidosis.

Guideline: Vulvovaginal candidosis (AWMF 015/072, level S2k)

Approximately 70-75% of women will have vulvovaginal candidosis (VVC) at least once in their lifetime. In premenopausal, pregnant, asymptomatic and healthy women and women with acute VVC, Candida albicans is the predominant species. The diagnosis of VVC should be based on clinical symptoms and microscopic detection of pseudohyphae. Symptoms alone do not allow reliable differentiation of the causes of vaginitis. In recurrent or complicated cases, diagnostics should involve fungal culture with species identification. Serological determination of antibody titres has no role in VVC. Before the induction of therapy, VVC should always be medically confirmed. Acute VVC can be treated with local imidazoles, polyenes or ciclopirox olamine, using vaginal tablets, ovules or creams. Triazoles can also be prescribed orally, together with antifungal creams, for the treatment of the vulva. Commonly available antimycotics are generally well tolerated, and the different regimens show similarly good results. Antiseptics are potentially effective but act against the physiological vaginal flora. Neither a woman with asymptomatic colonisation nor an asymptomatic sexual partner should be treated. Women with chronic recurrent Candida albicans vulvovaginitis should undergo dose-reducing maintenance therapy with oral triazoles. Unnecessary antimycotic therapies should always be avoided, and non-albicans vaginitis should be treated with alternative antifungal agents. In the last 6 weeks of pregnancy, women should receive antifungal treatment to reduce the risk of vertical transmission, oral thrush and diaper dermatitis of the newborn. Local treatment is preferred during pregnancy.

Recent Advances in Vaginal Delivery for the Treatment of Vulvovaginal Candidiasis

BACKGROUND

Vulvovaginal candidiasis (VVC) is a common vaginal infection caused by candida species, affecting 70% of the women. It may occur due to the imbalance in the vaginal micro- biodata, pregnancy, diabetes, use of antibiotics, frequent sexual activities or AIDS.

AIM

The main aim of this review is to provide overview about different vaginal delivery systems for the administration of antifungal agents like conventional, mucoadhesive and muco-penetrating delivery systems.

METHOD

The conventional delivery systems available have limited efficacy due to the less residence time and adverse effects. In order to overcome these issues, a delivery system with mucoadhesive and muco-penetrating properties is required. Mucoadhesive polymers have excellent binding properties with mucin and thus increasing residence time. On the other hand, muco-penetrating polymers transport the antifungal agents across the mucus layer.

RESULTS

This review summarizes the pathophysiology of VVC along with novel delivery systems for the treatment of infection through mucoadhesive and muco-penetrating approaches. Surface modifications of nano/ microparticles with mucoadhesive or muco-penetrating particles may provide delivery systems with improved therapeutic efficacy.

CONCLUSION

Based on the available data, conventional and mucoadhesive drug delivery systems have some limitations, they still require improvement/ development for safe and effective delivery of antifungal agents.

Antifungal, anti-inflammatory and antioxidant activity of bi-herbal mixtures with medicinal plants from Argentinean highlands

ETHNOPHARMACOLOGICAL RELEVANCE

Argentinean medicinal plants such as Larrea divaricata Cav., Larrea cuneifolia Cav., Larrea nitida Cav., Zuccagnia punctata Cav. and Tetraglochin andina Ciald. are used alone and in combination in traditional medicine by inhabitants from northwestern Argentina to solve mycosis, vaginal infections, gastrointestinal, respiratory, and inflammatory processes.

AIM OF THE STUDY

To assess the effect of interactions between hydroalcoholic extracts of these five species of medicinal plants against yeast strains isolated from vaginal infections, select the most active mixtures and evaluate anti-inflammatory and antioxidant activities.

MATERIAL AND METHODS

Synergy between the plant extracts was studied by using a broth microdilution assay by means of the checkerboard method against Saccharomyces cerevisiae, Candida albicans, and non albicans strains. The inhibitory effect on lipoxygenase and the antioxidant capacity in cell-free and cell systems were studied. The chemical profile was evaluated by qualitative and quantitative screening, whereas chemical markers were quantified by HPLC-DAD.

RESULTS

A synergistic antifungal effect was observed in some binary combinations. Z. punctata/L. divaricata, Z. punctata/L. cuneifolia, and Z. punctata/L. nitida were the most active mixtures. Nordihydroguaiaretic acid and 2',4'-dihydroxychalcone, two antifungal compounds, present in these extracts, were identified and quantified by HPLC-DAD. Both single extracts and bi-herbal mixtures showed antioxidant activity (in cellular and in cell-free systems) and were active on pro-inflammatory enzymes (LOX).

CONCLUSIONS

Our results indicated that the most active combinations of these species extracts could be useful in the treatment of vaginal infectious diseases caused by Saccharomyces cerevisiae and Candida spp. strains and in associated oxidative and inflammatory processes, supporting its traditional use. In addition, the results highlighted the phyto-therapeutic potential of total phytochemical compounds present in these medicinal plants.

Use of Lactobacillus crispatus to produce a probiotic cheese as potential gender food for preventing gynaecological infections

This research is aimed to evaluate the suitability of Squacquerone cheese to support the viability of Lactobacillus crispatus BC4, a vaginal strain endowed with a strong antimicrobial activity against urogenital pathogens and foodborne microorganisms, in order to recommend a gender food for woman wellbeing. The viability of L. crispatus BC4, used as adjunct culture, was evaluated during the refrigerated storage of Squacquerone cheese, as well as when the cheese was subjected to simulated stomach-duodenum passage tested by the patented Simulator of the Human Intestinal Microbial Ecosystem (SHIME). Moreover, the effects of L. crispatus BC4 addition were evaluated on product hydrolytic patterns, in terms of proteolysis, lipolysis and volatile molecule profiles. The data showed that L. crispatus BC4 maintained high viability, also in presence of physiological stress conditions, until the end of the refrigerated storage. Moreover, the inclusion of L. crispatus BC4 gave rise to cheese product with higher score of overall acceptability when compared to control cheese. In addition, the survival of L. crispatus BC4, carried in test cheese, in gastro intestinal conditions was confirmed by SHIME. The results showed that the vaginal Lactobacillus strain was more affected by the low pH of the stomach, simulated by the SHIME reactor, rather than to bile salts and pancreatic juices. Although only in vivo trials will be able to confirm the functionality of the cheese in the vaginal environment, these data represent a first step towards the employment of the Squacquerone cheese as probiotic food able to promote the woman’s health by preventing gynaecological infections.

Prevalence and antifungal susceptibility profiles of Candida glabrata, Candida parapsilosis and their close-related species in oral candidiasis

OBJECTIVE

To evaluate the importance of Candida glabrata, Candida parapsilosis and their close-related species, Candida bracarensis, Candida nivariensis, Candida metapsilosis and Candida orthopsilosis in patients with oral candidiasis and, to determine the in vitro activities of antifungal drugs currently used for the treatment.

METHODS

One hundred fourteen isolates of C. glabrata and 97 of C. parapsilosis, previously identified by conventional mycological methods, were analysed by molecular techniques. In vitro antifungal susceptibility to fluconazole, itraconazole, miconazole, and nystatin was evaluated by CLSI M44-A2 disk diffusion test, and by CLSI M27-A3 microdilution for fluconazole.

RESULTS

All C. glabrata isolates were identified as C. glabrata sensu stricto, 93 out of 97 C. parapsilosis isolates as C. parapsilosis sensu stricto, three as C. orthopsilosis and one as C. metapsilosis. Candida glabrata was mainly isolated in mixed cultures but C. parapsilosis complex was more frequent in pure culture. Candida metapsilosis and C. orthopsilosis were isolated as pure culture and both species were susceptible to all antifungal agents tested. Most C. glabrata isolates were susceptible to miconazole and nystatin, but resistant to fluconazole and itraconazole. Azole cross resistance was also observed. Candida parapsilosis isolates were susceptible to fluconazole although azole cross resistance to miconazole and itraconazole was observed.

CONCLUSION

This study highlights the importance of accurate identification and antifungal susceptibility testing of oral Candida isolates in order to have an in-depth understanding of the role of C. glabrata and C. parapsilosis in oral candidiasis.

Argentinean Larrea Dry Extracts with Potential Use in Vaginal Candidiasis

Larrea divaricata (Ld), Larrea cuneifolia (Lc) and Larrea nitida (Ln) are shrubs occurring in Northwestern Argentina used in traditional medicine to treat fungal and bacterial infections and as anti-inflammatory. Antibacterial and antifungal activity of several Larrea species has been reported. However, their potential use in vaginal infections has been so far not assessed. The aim of this work was to determine the botanical difference between Larrea species, the chemical composition and the activity of Larrea dry extracts (DE) on Candida species isolated from vaginal infections and to assess their potential as antioxidant agents because infections are usually associated with oxidative processes. The main botanical difference between Larrea species resides in the morphology and shape of leaf, leaflets and stipules, presence or absence of mucron and rachis, percentage of coalescence of the leaflets. The position and abundance of the sclerenchymatic tissue at the mind vein and petiole transection allows the differentiation of the three species. The profile of phenolic compounds in the Larrea DE was determined. HPLC-ESI-MS/MS analysis of DE allowed the identification of 2 flavonoids and 10 lignans. Trihydroxy-6,7′cyclolignan was found only in L. divaricata and dihydroxy-methoxy-epoxylignan in L. cuneifolia and L. nitida, nordihydroguaiaretic acid (NDGA) was found in the three species. All extracts showed antioxidant capacity. The DE showed to be effective against Candida albicans and non-albicans strains. According to our results, the local vaginal use of Larrea DE in the concentration range of MIC values for Candida species does not affect the Lactobacillus normal vaginal microbiota. This work adds evidence to the potential use of Larrea DE as phytomedicine in vulvovaginal candidiasis with multiple effects, including antifungal and antioxidant activity.

Novel mixed vesicles containing lactobacilli biosurfactant for vaginal delivery of an anti-Candida agent

The purpose of this work was to prepare and characterize an innovative formulation for vaginal delivery of econazole nitrate, commonly used for the treatment of Candida infections. A novel biosurfactant isolated from a vaginal Lactobacillus strain was used to prepare phosphatidylcholine based mixed vesicles. Biosurfactant was produced by Lactobacillus gasseri BC9, isolated from the vagina of a healthy premenopausal woman, and was chemically characterized by FT-IR and ESI-MS. Mixed vesicles, obtained through film rehydration and extrusion method, were characterized in terms of size, zeta potential, encapsulation efficiency, mucoadhesion properties and econazole release. Moreover, the antimicrobial activity of the mixed vesicles was tested towards both planktonic cultures and biofilms of Candida albicans. Biosurfactant produced by L. gasseri BC9 was composed by peptide-like molecules containing hydrocarbon chains and possessed a high surface activity together with a low critical micelle concentration. All the mixed vesicles presented optimal diameter range (226-337nm) for topical vaginal administration. Econazole-loaded mixed vesicles containing biosurfactant showed higher encapsulation efficiency and mucoadhesion ability with respect to vesicles containing Tween 80. Further, they allowed a sustained release of econazole nitrate, maintaining the antifungal activity against C. albicans planktonic culture. Notably, biosurfactant-based vesicles were significantly more active than free econazole in the eradication of Candida biofilm. In conclusion, mixed vesicles are promising new vaginal delivery systems for the potential employment in the treatment of chronic infections.

Determination of Antibacterial and Technological Properties of Vaginal Lactobacilli for Their Potential Application in Dairy Products

Functional foods could differently affect human health in relation to the gender. Recent studies have highlighted the anti-Candida and anti-Chlamydia activities of some Lactobacillus strains isolated from the vagina of healthy women. Considering these important beneficial activities on women's health, the preparation of functional food containing active vaginal lactobacilli can represent a great scientific challenge for the female gender. In this context, the aim of this work was to study some functional and technological properties of 17 vaginal strains belonging to the species Lactobacillus crispatus, Lactobacillus gasseri, and Lactobacillus vaginalis in the perspective to include them in dairy products. The antagonistic activities against the pathogenic and spoilage species associated to food products and against the principal etiological agents of the genitourinary tract infections were evaluated. Moreover, the vaginal lactobacilli were characterized for their antibiotic resistance, and for their fermentation kinetics and viability during the refrigerated storage in milk. Finally, the volatile molecule profiles of the obtained fermented milks were determined. The results showed that several strains, mainly belonging to the species Lactobacillus crispatus, exhibited a significant antagonistic activity against spoilage and pathogenic microorganisms of food interest, as well as against urogenital pathogens. All the vaginal lactobacilli showed antimicrobial activity against strains belonging to the foodborne pathogenic species Listeria monocytogenes, Listeria innocua, Eenterococcus faecalis and Escherichia coli. In addition, most of the Lactobacillus strains were active toward the main pathogens responsible of vaginal and urinary tract infections including Staphylococcus aureus, Enterococcus faecium, Gardnerella vaginalis, and Proteus mirabilis. The antimicrobial activity can be attributed to the high production of organic acids. The fermentation kinetics in milk indicated the unsuitability of these lactobacilli as fermentation starters for the industrial production of dairy products. However, some strains, belonging to the species Lactobacillus crispatus and Lactobacillus gasseri, maintained a high viability in pasteurized milk at 4°C for over a month, showing their potential application as adjunct cultures for the production of female gender foods. These data represent a first step for the set-up of a new functional dairy product, directed to the women well-being, contributing also to innovate the dairy sector.

Polymer-based nanocarriers for vaginal drug delivery

The vaginal delivery of various drugs is well described and its relevance established in current medical practice. Alongside recent advances and achievements in the fields of pharmaceutical nanotechnology and nanomedicine, there is an increasing interest in the potential use of different nanocarriers for the delivery of old and new pharmacologically active molecules with either therapeutic or prophylactic purposes. Nanosystems of polymeric nature in particular have been investigated over the last years and their interactions with mucosal fluids and tissues, as well as genital tract biodistribution upon vaginal administration, are now better understood. While different applications have been envisioned, most of the current research is focusing in the development of nano-formulations with the potential to inhibit the vaginal transmission of HIV upon sexual intercourse. The present work focuses its discussion on the potential and perils of polymer-based nanocarriers for the vaginal administration of different pharmacologically active molecules.

Polymeric films as a promising carrier for bioadhesive drug delivery: Development, characterization and optimization

Bioadhesive films using tamarind seed polysaccharide were prepared for the treatment of candida vaginitis using nystatin as the model drug. Films were prepared by solvent casting method. A 3² factorial design was employed to study the effect of independent variables (polymer and plasticizer concentration) on a range of dependent variables namely mechanical, swelling, interfacial, and bioadhesive properties through response surface methodological approach, using Design Expert® software. Formulation composition that provided the most desired and optimized results was selected using desirability approach. Nystatin was solubilized using Tween 60 and was incorporated into the selected film. Drug solubilization and dispersion were confirmed by scanning electron microscopy and differential scanning calorimetry. The optimized film released 73.92 ± 2.54% of nystatin at the end of 8 h in simulated vaginal fluid and the release data showed best fit to Korsmeyer–Peppas model with R² of 0.9990 and the release mechanism to be super case-II. The optimized film also showed appropriate anti candida activity through appearance of zone of inhibition during antifungal activity testing study.

Chitosan-coated liposomes for topical vaginal therapy: assuring localized drug effect

The choice of drug therapy in pregnant patients suffering from vaginal infections is limited by the safety profile of the drug. Assuring the efficient topical therapy to avoid systemic absorption is considered the best therapy option. Chitosan-coated liposomes have been developed and optimized to assure localized therapy of clotrimazole. Chitosan was selected as mucoadhesive polymer both to prolong system's retention at the vaginal site and act on biofilms responsible for high recurrence of infections. Sonicated liposomes were coated with chitosan in three different concentrations, namely 0.1, 0.3 and 0.6% (w/v). Clotrimazole-containing (22 μg/mg lipid) chitosan-coated liposomes were in the size range of 100-200 nm. The in vitro release studies confirmed prolonged release of clotrimazole from both non-coated and chitosan-coated liposomes as compared to control. The ex vivo penetration experiments performed on the pregnant sheep vaginal tissue showed that coated liposomes assured increased clotrimazole tissue retention and reduced its penetration as compared to the control. Mucin studies revealed that the coating with lower chitosan concentration increased the system's mucoadhesive potential, as compared to coating with higher concentrations. These results provide a good platform for further in vivo animal studies on mucoadhesive liposomes destined to localized vaginal therapy.

Pregnancy, breast-feeding and drugs used in dentistry

BACKGROUND AND OVERVIEW

Despite advances in the study of birth defects related to drug exposures during pregnancy, medication use during pregnancy still causes anxiety and misunderstanding among both members of the public and health care professionals. This may result in a woman's unknowingly taking a medication that may harm the fetus or cause a birth defect or discontinuing medications necessary for treating chronic conditions. Using medications while breast-feeding also represents a challenge for patients and prescribers. Many mothers are told they must stop breast-feeding or "pump and discard" their breast milk if they are taking certain medications; however, in many cases, this advice-based on what may be limited education on the part of the health care provider about breast-feeding and medication use-may be incorrect. The authors review the current evidence regarding drugs that may be safe for pregnant or breast-feeding patients and medications that such patients should avoid.

CONCLUSIONS

When considering prescribing in pregnancy, the dentist must weigh the risk to the fetus versus the benefit to the mother, and the appropriate conclusion should reflect current evidence. In some cases medication dosing should be avoided or altered; however, there are times when it is unnecessary to stop the use of medications. Breast-feeding also represents a clinical challenge, the risks and benefits of which need to be understood by both the patient and practitioner before any medication is administered.

PRACTICE IMPLICATIONS

Dentists should be familiar with the risks and benefits for pregnant or breast-feeding patients posed by five types of medications: analgesics and anti-inflammatories, antibiotics, local anesthetics, sedatives and emergency medications.

In vitro assessment of gentian violet anti- candida activity

BACKGROUND/AIM

Recurrent vulvovaginal candidosis (RVVC) needs alternative therapeutic approaches. Gentian violet (GeV) has been traditionally used to treat mucocutaneous candidosis. The aim of the present study was to evaluate the in vitro activity of GeV against Candida spp. and contribute to clarify the mechanism of action, supporting its clinical therapeutic use.

METHODS

Seventeen clinical Candida isolates from RVVC and one C. albicans type collection (ATCC 10231) were studied; the antifungal activity of GeV was evaluated according to the CLSI M27-A3 protocol. To elucidate its mechanism of action, cells were stained with propidium iodide and afterwards analyzed by flow cytometer.

RESULTS

GeV showed a fungicidal activity against most Candida spp. C. albicans and C. tropicalis were the most susceptible species. Minimal lethal concentrations were similar to minimal inhibitory concentrations for most tested strains. The fungicidal effect was not related to a primary lesion of the cytoplasmic membrane.

CONCLUSION

In accordance with our findings, GeV is a valuable potent fungicidal drug to be used topically, isolated or in combination with oral antifungal drugs, particularly in RVVC cases.

A chitosan lactate/poloxamer 407-based matrix containing Eudragit RS microparticles for vaginal delivery of econazole: design and in vitro evaluation

A matrix based on chitosan lactate and poloxamer 407 was evaluated as a delivery system for the vaginal administration of the antifungal drug econazole. The matrix was investigated both containing the pure drug and after introducing microparticles of Eudragit RS 100 containing econazole. Eudragit RS 100 microparticles were prepared using an emulsion-extraction method and dispersed in a solution containing chitosan lactate (2% w/w) and poloxamer 407 (1.7% w/w). The microparticles, obtained with a yield of 64% w/w and an encapsulation efficiency of 42% w/w, had a diameter of less than 2 μm and a drug loading of 13% w/w. The compressed matrices, characterized by DSC, swelling, erosion, release and mucoadhesion studies, had behaviours dependent on the relative amounts of the contained microparticles. The matrix without microparticles (MECN) showed zero-order release kinetics, with a maximum drug-release of 60% w/w, while those containing 50 or 75% w/w microparticles showed a diffusion controlled release up to 8 and 16 h, respectively, and a linear trend after those time intervals, caused by the erosion process, which allowed reaching a drug-release of approximately 100% w/w at 22 h. In in vitro experiments, the matrices were mucoadhesive and active in inhibiting the growth of Candida albicans 796.

Therapeutic use of a cationic antimicrobial peptide from the spider Acanthoscurria gomesiana in the control of experimental candidiasis

Background

Antimicrobial peptides are present in animals, plants and microorganisms and play a fundamental role in the innate immune response. Gomesin is a cationic antimicrobial peptide purified from haemocytes of the spider Acanthoscurria gomesiana. It has a broad-spectrum of activity against bacteria, fungi, protozoa and tumour cells. Candida albicans is a commensal yeast that is part of the human microbiota. However, in immunocompromised patients, this fungus may cause skin, mucosal or systemic infections. The typical treatment for this mycosis comprises three major categories of antifungal drugs: polyenes, azoles and echinocandins; however cases of resistance to these drugs are frequently reported. With the emergence of microorganisms that are resistant to conventional antibiotics, the development of alternative treatments for candidiasis is important. In this study, we evaluate the efficacy of gomesin treatment on disseminated and vaginal candidiasis as well as its toxicity and biodistribution.

Results

Treatment with gomesin effectively reduced Candida albicans in the kidneys, spleen, liver and vagina of infected mice. The biodistribution of gomesin labelled with technetium-99 m showed that the peptide is captured in the kidneys, spleen and liver. Enhanced production of TNF-α, IFN-γ and IL-6 was detected in infected mice treated with gomesin, suggesting an immunomodulatory activity. Moreover, immunosuppressed and C. albicans-infected mice showed an increase in survival after treatment with gomesin and fluconazole. Systemic administration of gomesin was also not toxic to the mic

Conclusions

Gomesin proved to be effective against experimental Candida albicans infection. It can be used as an alternative therapy for candidiasis, either alone or in combination with fluconazole. Gomesin's mechanism is not fully understood, but we hypothesise that the peptide acts through the permeabilisation of the yeast membrane leading to death and/or releasing the yeast antigens that trigger the host immune response against infection. Therefore, data presented in this study reinforces the potential of gomesin as a therapeutic antifungal agent in both humans and animals.

The relationship between Candida species charge density and chitosan activity evaluated by ion-exchange chromatography

Chitosan, a natural biopolymer presents antifungal activity that seems to be dependent on the interaction of its cationic amino groups and yeast cell surface. In this work we used ion-exchange chromatography to assess the surface charge density of Candida species and subsequently to relate this with their sensitivity profile to chitosan. The ability of several strains from distinct Candida species to interact with strong anionic and cationic exchangers was tested and the yeasts charge surface was assessed by measuring the zeta potential. Our results showed that all the yeast cells tested presented no interaction with the cationic resin and a species-related pattern of interaction was observed with the anionic resin. Specifically, regarding the Q-Sepharose support, Candida glabrata showed the lower retention affinity, followed by Candida albicans, presenting Candida tropicalis an intermediate profile; Candida parapsilosis and Candida guilliermondii revealed a stronger ionic interaction. The yeasts retention synergy in the anionic resin corroborates with the zeta potential outcomes. The behavior observed fit with sensitivity patterns to chitosan as the most susceptible species to chitosan presented higher affinity to the anionic resin in contrast to the less sensitive ones (C. albicans and C. glabrata). This data confirms and reinforces that chitosan activity is probably mediated by an ionic reaction between its amino free groups and ionic charges at the cell surface.

Patient preferences and treatment safety for uncomplicated vulvovaginal candidiasis in primary health care

Background

Vaginitis is a common complaint in primary care. In uncomplicated candidal vaginitis, there are no differences in effectiveness between oral or vaginal treatment. Some studies describe that the preferred treatment is the oral one, but a Cochrane's review points out inconsistencies associated with the report of the preferred way that limit the use of such data. Risk factors associated with recurrent vulvovaginal candidiasis still remain controversial.

Methods/Design

This work describes a protocol of a multicentric prospective observational study with one year follow up, to describe the women's reasons and preferences to choose the way of administration (oral vs topical) in the treatment of not complicated candidal vaginitis. The number of women required is 765, they are chosen by consecutive sampling. All of whom are aged 16 and over with vaginal discharge and/or vaginal pruritus, diagnosed with not complicated vulvovaginitis in Primary Care in Madrid.

The main outcome variable is the preferences of the patients in treatment choice; secondary outcome variables are time to symptoms relief and adverse reactions and the frequency of recurrent vulvovaginitis and the risk factors. In the statistical analysis, for the main objective will be descriptive for each of the variables, bivariant analysis and multivariate analysis (logistic regression).. The dependent variable being the type of treatment chosen (oral or topical) and the independent, the variables that after bivariant analysis, have been associated to the treatment preference.

Discussion

Clinical decisions, recommendations, and practice guidelines must not only attend to the best available evidence, but also to the values and preferences of the informed patient.

Therapeutic efficacy of voriconazole against a fluconazole-resistant Candida albicans isolate in a vaginal model

BACKGROUND

The purpose of this study was to assess the therapeutic efficacy of oral versus intravaginal voriconazole and compare it with fluconazole for the treatment of experimental vaginitis caused by a fluconazole-resistant Candida albicans isolate.

METHODS

Mice were treated with voriconazole at 5, 10 and 20 mg/kg once a day and 20 mg/kg twice a day or with fluconazole at 20 mg/kg once or twice a day orally. Intravaginal treatments were evaluated with voriconazole and fluconazole at 0.5, 1 and 5 mg/kg once a day. All treatment regimens were given on days 1-5 post-challenge. One day 6, the vaginas were swabbed to assess treatment effects.

RESULTS

Mice treated orally with voriconazole at >or=10 mg/kg and fluconazole at >or=20 mg/kg showed significantly reduced fungal counts over controls (P = 0.0002-0.007). Significant differences were found between the groups that received voriconazole at 20 mg/kg once or twice daily and those that received fluconazole at 20 mg/kg once or twice daily, orally (P = 0.010 and 0.001, respectively). Mice treated with voriconazole or fluconazole administered intravaginally at >or=0.5 mg/kg exhibited a reduced fungal burden when compared with the control group (P = 0.0002-0.007). There was no statistically significant difference in fungal burden between topical treatment with doses of 0.5, 1 and 5 mg/kg once daily of voriconazole or fluconazole. Sterilization of vaginas was not observed with voriconazole and fluconazole without taking into consideration the therapeutic modality.

CONCLUSIONS

Voriconazole could emerge as a new alternative for treatment of vaginal candidosis.

Fenticonazole activity measured by the methods of the European Committee on Antimicrobial Susceptibility Testing and CLSI against 260 Candida vulvovaginitis isolates from two European regions and annotations on the prevalent genotypes

The activity of fenticonazole was studied against 260 West and Southeast European vulvovaginal candidiasis isolates, and low MICs were displayed. Fenticonazole was assessed by European Committee on Antimicrobial Susceptibility Testing and CLSI microdilution methods for the first time, and the results showed excellent agreement (97%) and significant interclass correlation coefficient (P < 0.0001). Also, the levels of agreement for the results for itraconazole, fluconazole, and ketoconazole were 84%, 90%, and 98% (P < 0.0001), respectively. Multilocus typing by PCR fingerprinting and subsequent cluster analysis delineated geographically associated alignments for Candida albicans and fluconazole resistance-related clusters for Candida glabrata.