Gynecologic oncology patients are ready for telemedicine in routine care: Results from a pre-COVID survey.

OBJECTIVES: To assess telemedicine readiness of gynecologic oncology patients, particularly those at risk for care access disparities (increased distance to care, rural populations.). METHODS: Patients at all disease/treatment stages completed an anonymous survey during in-person outpatient appointments at an academic comprehensive cancer center from 1/6/2020 to 2/28/2020, conducted prior to the COVID-19 pandemic, before the introduction of telemedicine in this practice. RESULTS: Of 180 patients approached, 170 completed the survey (94.4%). Mean age was 59.6 years; 73.4% identified as White, 23.7% Black, and 2.9% other race. Ovarian cancer was most common (41.2%), followed by endometrial (27.1%), cervical (20.6%), and vaginal/vulvar (7.1%). Most patients traveled > 50 miles for appointments (63.8%); they were more likely from rural counties with significantly higher travel costs/visit ($60.77 vs $37.98, p = 0.026.) The majority expressed interest in using telemedicine (75.7%) or a smartphone app (87.5%) in their care. The majority of patients with difficulty attending appointments (88.9 vs 70.2%, p = 0.02) or from rural counties (88.7% vs 69.6%, p = 0.03) were interested in telemedicine; those with both characteristics reported 100% interest. The majority in both urban and rural counties had home internet access, and reported similarly high rates of daily use (79% vs 75%). Race and age were not associated with differences in internet access or use or telemedicine interest. CONCLUSIONS: Telemedicine is attractive to the majority of patients and may offer financial/logistical advantages. Patients have high internet use rates and comfort with using technology for healthcare. Telemedicine should be incorporated into standard practice beyond the COVID-19 pandemic to reduce healthcare access disparities.

Cluster intradermal DNA vaccination rapidly induces E7-specific CD8+ T-cell immune responses leading to therapeutic antitumor effects.

Intradermal administration of DNA vaccines via a gene gun represents a feasible strategy to deliver DNA directly into the professional antigen-presenting cells (APCs) in the skin. This helps to facilitate the enhancement of DNA vaccine potency via strategies that modify the properties of APCs. We have previously demonstrated that DNA vaccines encoding human papillomavirus type 16 (HPV-16) E7 antigen linked to calreticulin (CRT) are capable of enhancing the E7-specific CD+ T-cell immune responses and antitumor effects against E7-expressing tumors. It has also been shown that cluster (short-interval) DNA vaccination regimen generates potent immune responses in a minimal time frame. Thus, in the current study we hypothesize that the cluster intradermal CRT/E7 DNA vaccination will generate significant antigen-specific CD8+ T-cell infiltrates in E7-expressing tumors in tumor-bearing mice, leading to an increase in apoptotic tumor cell death. We found that cluster intradermal CRT/E7 DNA vaccination is capable of rapidly generating a significant number of E7-specific CD8+ T cells, resulting in significant therapeutic antitumor effects in vaccinated mice. We also observed that cluster intradermal CRT/E7 DNA vaccination in the presence of tumor generates significantly higher E7-specific CD8+ T-cell immune responses in the systemic circulation as well as in the tumors. In addition, this vaccination regimen also led to significantly lower levels of CD4+Foxp3+ T-regulatory cells and myeloid suppressor cells compared to vaccination with CRT DNA in peripheral blood and in tumor-infiltrating lymphocytes, resulting in an increase in apoptotic tumor cell death. Thus, our study has significant potential for future clinical translation.

Congenital acantholytic dyskeratotic epidermal naevus following Blaschko's lines versus segmental Darier's disease.

A Japanese newborn male with an unremarkable family history presented at birth with verrucous papules on the left side of the trunk and limbs, distributed along Blaschko's lines. Histological examination showed mild acantholytic dyskeratosis, consistent with Darier's disease; however, search for mutations of the SERCA gene, performed on DNA extracted from cells from involved and uninvolved skin and peripheral blood proved negative. The absence of detectable SERCA mutations did not allow confirmation of the diagnosis of (segmental) Darier's disease, and a tentative diagnosis of congenital acantholytic dyskeratotic epidermal nevus was considered. The relationship between the two conditions is briefly discussed.

D-arabinose dehydrogenase and its gene from Saccharomyces cerevisiae.

D-Arabinose dehydrogenase was purified 843-fold from the cytosolic fraction of Saccharomyces cerevisiae with a recovery of 9%. The purified enzyme gave two bands with a molecular mass of 40 and 39 kDa on SDS-PAGE. The native enzyme had a molecular mass of 74 kDa as estimated by Sephacryl S-200 chromatography. Therefore, this enzyme was considered to be a heterodimer. The purified enzyme exhibited maximum activity at pH 10.0 and around 30 degrees C. The enzyme catalysed the oxidation of D-arabinose, L-xylose, L-fucose and L-galactose in the presence of NADP+. The apparent Km values at pH 10.0 with 50 microM NADP+ for D-arabinose, L-xylose, L-fucose, and L-galactose were 161, 24, 98 and 180 mM, respectively. The pH profile of Vmax and kcat/Km showed one ionisable groups around pH 8.3. D-Erythroascorbic acid was formed in vitro from D-arabinose by D-arabinose dehydrogenase and D-arabinono-1,4-lactone oxidase. The N-terminal amino acid sequence of the heavy subunit was Ser-Thr-Glu-Asn-Ile-Val-Glu-Asn-Met-Leu-His-Pro-Lys-Thr-. The N-terminus of the light subunit was blocked. The obtained peptide sequence was identical to the translational product of an unknown open reading frame, YBR149W, in chromosome II of S. cerevisiae. When compared with the translational product of this open reading frame, the peptide sequence was identical to the amino acid sequences of residues 7 to 20. The first six amino acids of this open reading frame were lost in protein sequence, which may be modified post-translationally. The heavy subunit was composed of 344 amino acid residues and its deduced amino acid sequence contained the motifs I, II, and III of aldo-keto reductase and also leucine zipper motif. This enzyme is the first heterodimeric protein of aldo-keto reductase family. In the deletion mutant of this gene, D-arabinose dehydrogenase activity and D-erythroascorbic acid were not detected.

D-arabinose dehydrogenase and biosynthesis of erythroascorbic acid in Candida albicans.

D-Arabinose dehydrogenase was purified 2750-fold from the cytosolic fraction of Candida albicans to apparent homogeneity, with an overall yield of 3%, by a purification procedure consisting of ammonium sulfate precipitation and DEAE-Sepharose A-50, Sephacryl S-200, Cibacron blue and phenyl-Sepharose CL-4B chromatographies. Gel-filtration chromatography gave an apparent molecular mass of 41 kDa and SDS-PAGE showed only one protein band corresponding to a molecular mass of 42 kDa, indicating that the enzyme is a single polypeptide. The enzyme was optimally active at pH 8.0 and the pI value of the enzyme was 5.0. The enzyme was relatively stable from pH 4.5 to 7.5. The optimal temperature for the enzyme activity was 30 degrees C. The activity of the enzyme was inhibited by Hg2+, Fe2+, Zn2+, Cu2+, Mg2+, Mn2+, N-ethylmaleimide and p-chloromercuribenzoic acid. The enzyme catalysed the oxidation of D-arabinose, L-fucose, L-xylose and L-galactose, which have the same configurations of hydroxyl groups at C2- and C3-positions, with apparent K(m) values of 29.2, 28.9, 37.1 and 91.3 mM at pH 8.0, respectively, with 50 microM NADP+. The enzyme used NADP+ as a coenzyme. Apparent K(m) value at 60 mM D-arabinose for NADP+ was 44.6 microM. NADPH inhibited the enzyme activity competitively with respect to NADP+ (Ki = 78.6 microM). The amino-terminal sequence of the enzyme was Met-Lys-Leu-Ala-Thr-Glu-Ile-Asp-Phe-X-Leu-Asn-Asn-Gly-. The reaction product was D-arabinono-1,4-lactone, judged from gas-liquid chromatography/mass spectrometry. In C. albicans, D-erythroascorbic acid was formed from D-arabinose by D-arabinose dehydrogenase and D-arabinono-1,4-lactone oxidase.

Mitochondrial NADH-cytochrome b(5) reductase plays a crucial role in the reduction of D-erythroascorbyl free radical in Saccharomyces cerevisiae.

The relevance of NADH-cytochrome b(5) reductase to the NADH-dependent reduction of D-erythroascorbyl free radical was investigated in Saccharomyces cerevisiae. MCR1, which is known to encode NADH-cytochrome b(5) reductase in S. cerevisiae, was disrupted by the insertion of URA3 gene into the gene of MCR1. In the mcr1 disruptant cells, the activity of NADH-D-erythroascorbyl free radical reductase almost disappeared and the intracellular level of D-erythroascorbic acid was about 11% of that of the congenic wild-type strain. In the transformant cells carrying MCR1 in multicopy plasmid, the intracellular level of D-erythroascorbic acid and the activity of NADH-D-erythroascorbyl free radical reductase increased up to 1.7-fold and 2.1-fold, respectively. Therefore, it indicated that the MCR1 product, mitochondrial NADH-cytochrome b(5) reductase, plays a key role in the NADH-dependent reduction of D-erythroascorbyl free radical in S. cerevisiae. On the other hand, the mcr1 disruptant cells were hypersensitive to hydrogen peroxide and menadione, and overexpression of MCR1 made the cells more resistant against oxidative stress. These results suggested that the mitochondrial NADH-cytochrome b(5) reductase functions as NADH-D-erythroascorbyl free radical reductase and plays an important role in the response to oxidative damage in S. cerevisiae.

Copper- and zinc-containing superoxide dismutase and its gene from Candida albicans.

Cytosolic copper- and zinc-containing superoxide dismutase was purified 136-fold with an overall yield of 2.5% to apparent electrophoretic homogeneity from the dimorphic pathogenic fungus, Candida albicans. The molecular mass of the native enzyme was 39.4 kDa and the enzyme was composed of two identical subunits with a molecular mass of 19.6 kDa. The enzyme was stable in the range of pH 4.0-9.0 and up to 55 degrees C. The ultraviolet-visible absorption spectrum of the enzyme showed the absorption band of copper- and zinc-containing superoxide dismutase at 660 nm. The atomic absorption analysis revealed that the enzyme contained 0.87 g-atom of copper and 0.79 g-atom of zinc per mole of subunit. The N-terminal amino acid sequence alignments up to the 40th residue showed that copper- and zinc-containing superoxide dismutase from C. albicans has high similarity to other eukaryotic copper- and zinc-containing superoxide dismutases. The sod1 encoding copper- and zinc-containing superoxide dismutase has been cloned using a polymerase chain reaction fragment as a probe. Sequence analysis of the sod1 predicted a copper- and zinc-containing superoxide dismutase that contains 154 amino acids with a molecular mass of 16143 Da and displayed 79%, 69%, and 57% sequence identity to the homologues of Neurospora crassa, Saccharomyces cerevisiae, and bovine, respectively. The cloned sod1 contained an intron of 245 nucleotides, which was verified by reverse transcription-polymerase chain reaction.

Manganese-containing superoxide dismutase and its gene from Candida albicans.

Mitochondrial manganese-containing superoxide dismutase was purified around 112-fold with an overall yield of 1.1% to apparent electrophoretic homogeneity from the dimorphic pathogenic fungus, Candida albicans. The molecular mass of the native enzyme was 106 kDa and the enzyme was composed of four identical subunits with a molecular mass of 26 kDa. The enzyme was not sensitive to either cyanide or hydrogen peroxide. The N-terminal amino acid sequence alignments (up to the 18th residue) showed that the enzyme has high similarity to the other eukaryotic manganese-containing superoxide dismutases. The gene sod2 encoding manganese-containing superoxide dismutase has been cloned using a product obtained from polymerase chain reaction. Sequence analysis of the sod2 predicted a manganese-containing superoxide dismutase that contains 234 amino acid residues with a molecular mass of 26173 Da, and displayed 57% sequence identity to the homologue of Saccharomyces cerevisiae. The deduced N-terminal 34 amino acid residues may serve as a signal peptide for mitochondrial translocation. Several regulatory elements such as stress responsive element and haem activator protein 2/3/4/5 complex binding sites were identified in the promoter region of sod2. Northern analysis with a probe derived from the cloned sod2 revealed a 0.94-kb band, which corresponds approximately to the expected size of mRNA deduced from sod2.

Confocal laser microscopic observation of glycocalyx production by Staphylococcus aureus in vitro.

We used a scanning confocal laser microscope to study the effects of various agents on sugar production by Staphylococcus aureus in vitro. S. aureus cells attached to coverslips in Pl-TSB (plasma:tryptic soy broth=1:1) were stained with fluorescein isothiocyanate-conjugated concanavalin A (FITC-conA) and were more strongly stained over time. We considered that the materials that stained positive for FITC-conA consistent with S. aureus cells were sugars, probably glycocalyx, produced by the S. aureus cells. Since the cells in the stationary growth phase alone were strongly stained with FITC-conA, all S. aureus cells attached to the coverslips in Pl-TSB were considered to be in this phase (low growth rate). The positive staining for FITC-conA was markedly reduced when fibrin was not formed in Pl-TSB with plasmin and sucrose, and was also markedly reduced when the fibrin in Pl-TSB was destroyed with plasmin. In conclusion, the results of the present study indicate that the existence of fibrin is essential for glycocalyx production and biofilm formation of S. aureus cells to aid in the attachment of S. aureus cells in vitro, because S. aureus cells attached on coverslips and fibrin alone produce glycocalyx. Of the antimicrobial agents tested, sulfadiazine silver most strongly inhibited the production of FITC-conA-positive materials by S. aureus cells at a sub-MIC concentration. Plasmin, sucrose, and sulfadiazine silver may be useful topical applications for use on clinical dermatology for the prevention and the treatment of staphylococcal biofilms. We consider that this simple method is very useful for the detection of S. aureus glycocalyx on dermatology field.

Human papillomavirus triage of patients with atypical squamous cells of undetermined significance on cervical Papanicolaou smear.

INTRODUCTION: The recent development of affordable human papillomavirus (HPV) testing has prompted consideration of its use as adjuvant and primary screening for cervical dysplasia. This review focuses on the use of HPV testing in triage management of atypical squamous cells of undetermined significance (ASC-US) Pap smears. MATERIALS AND METHODS: A Medline search was performed for articles relevant to HPV testing as a triage strategy for ASC-US Paps. Key references from other papers that were not included in the search were also reviewed. Findings from the major randomised trials were then summarised. RESULTS: Reflex HPV testing with hybrid capture is at least as effective and potentially cheaper than repeat cytology for evaluation of an ASC-US Pap. It also avoids 50% of colposcopies that would normally be performed if immediate colposcopy were done for all ASC-US Paps, while retaining excellent negative predictive value. CONCLUSION: Reflex HPV testing using liquid-based cytology is the preferred management strategy for triage of ASC-US Paps.

Outcomes for patients with fallopian tube carcinoma managed with adjuvant chemotherapy following primary surgery: a retrospective university experience.

The aim is to evaluate disease-free (DFS) and overall survival (OS) of patients with fallopian tube carcinoma (FTCA) treated with adjuvant chemotherapy. An Institutional Review Board approved retrospective review identified 38 patients with FTCA that received adjuvant chemotherapy following primary surgery from 1975 to 2001. Median age was 56 (range 36-78) and 95% of patients were white. Twenty patients (53%) had FIGO stage III/IV FTCA. Seventeen patients underwent second-look laparotomy, 8 (47%) patients were found to have disease. Adjuvant chemotherapeutic regimens consisted of melphalan in 11 patients, platinum-based chemotherapy without paclitaxel in 17 patients, and the combination of paclitaxel and platinum in 10 patients. Although DFS was similar for the three chemotherapy cohorts (P= 0.19), patients receiving paclitaxel had superior OS compared to patients receiving either melphalan (P= 0.02) or platinum without paclitaxel (P= 0.04). Of the twenty patients with stage III/IV disease, 55% of patients had optimal cytoreduction performed at their initial surgery. Both median DFS, 68 versus 50 months (P= 0.14) and OS, 73 versus 50 months (P= 0.12) were greater in patients with optimal cytoreduction. When compared to historical chemotherapeutic regimens, the combination of paclitaxel and platinum has superior efficacy for the management of patients with FTCA. Although not statistically significant in our study, optimal cytoreduction likely improves both DFS and OS and should be the goal of all patients surgically managed for FTCA.

Prevalence and distribution of HPV genotypes among HIV-infected women in Zambia.

We screened 145 HIV-infected non-pregnant women at a tertiary care centre in Lusaka, Zambia. Liquid-based cytology and human papillomavirus (HPV) genotyping with PGMY09/11 biotinylated primers (Roche Linear Array HPV genotyping test) maximised sensitivity of cytology and HPV assessments. Among high-risk (HR) types, HPV 52 (37.2%), 58 (24.1%) and 53 (20.7%) were more common overall than HPV 16 (17.2%) and 18 (13.1%) in women with high-grade squamous intraepithelial lesions or squamous cell carcinoma (SCC) on cytology. High-risk HPV types were more likely to be present in women with CD4+ cell counts <200 microl(-1) (odds ratios (OR): 4.9, 95% confidence intervals (CI): 1.4-16.7, P=0.01) and in women with high-grade or severe cervical cytological abnormalities (OR: 8.0, 95% CI: 1.7-37.4, P=0.008). Human papillomavirus diversity in high-grade lesions and SCC on cytology suggests that HPV 16- and 18-based vaccines may not be adequately polyvalent to induce protective immunity in this population.

Salvage of isolated vaginal recurrences in women with surgical stage I endometrial cancer: a multiinstitutional experience.

The objective of this study was to evaluate the treatment outcomes and risk factors of women with surgical stage I endometrial adenocarcinoma who were initially treated with surgery alone and subsequently developed isolated vaginal recurrences. Patients with surgical stage I endometrial adenocarcinoma diagnosed from 1975 to 2002 were identified from tumor registry databases at seven institutions. All patients were treated with surgery alone including a total hysterectomy, bilateral salpingo-oophorectomy, pelvic (+/- para-aortic) lymph node dissection, and peritoneal cytology and did not receive postoperative radiation therapy. Vaginal recurrences were documented histologically. Metastatic disease in the chest and abdomen was excluded by radiologic studies. Overall survival was calculated by the Kaplan-Meier method. Sixty-nine women with surgical stage I endometrial cancer with isolated vaginal recurrences were identified. Of the 69 patients, 10 (15%) were diagnosed with stage IA disease, 43 (62%) were diagnosed with stage IB disease, and 16 (23%) were diagnosed with stage IC disease. Patients diagnosed with grade 1 disease were 22 (32%), grade 2 disease were 26 (38%), and grade 3 disease were 21 (30%). Among women, 81% with isolated vaginal recurrences were salvaged with radiation therapy. The mean time to recurrence was 24 months, and the mean follow-up was 63 months. Among women, 18% died from subsequent recurrent disease. The 5-year overall survival was 75%. The majority of isolated vaginal recurrences in women with surgical stage I endometrial cancer can be successfully salvaged with radiation therapy, further questioning the role of adjuvant therapy for patients with uterine-confined endometrial cancer at the time of initial diagnosis.

Characterization of the gene family encoding alternative oxidase from Candida albicans.

Candida albicans possesses a cyanide-resistant respiratory pathway mediated by alternative oxidase (AOX), which seems to be encoded by a gene family with two members. Cloning and expression of AOX1a, one of the genes encoding alternative oxidase from C. albicans, has previously been reported [Huh and Kang (1999) J. Bacteriol. 181, 4098-4102]. In the present study we report the isolation of another gene coding for alternative oxidase, designated AOX1b. AOX1b contains a continuous open reading frame that encodes a polypeptide consisting of 365 amino acids. Interestingly, AOX1a and AOX1b were found to be located in tandem on one of the chromosomes of C. albicans. The presence of cyanide in the culture medium remarkably retarded the growth of the aox1a/aox1a mutants. The growth of the aox1b/aox1b mutants and the aox1a/aox1a aox1b/aox1b double mutants was almost completely inhibited in the same medium. beta-Galactosidase reporter assays indicated that, whereas AOX1a was expressed constitutively, the expression of AOX1b was dependent on growth phase and was induced by treatment with cyanide, antimycin A, H(2)O(2), menadione and paraquat. Growth of the cells in media with non-fermentable carbon sources also enhanced the expression of AOX1b. CaSLN1, which encodes a histidine kinase, seems to be involved in the regulation of AOX expression in C. albicans on the basis of the observation that the activity of cyanide-resistant respiration and the expression level of AOX in the casln1/casln1 mutants were found to be significantly low under normal conditions and slightly increased in the presence of respiratory inhibitors compared with the wild-type strain. Like AOX1a, AOX1b could also be functionally expressed in AOX-deficient Saccharomyces cerevisiae and confer cyanide-resistant respiration on the organism.

Altered restriction patterns of microwave irradiated lambdaphage DNA.

Samples of lambdaphage DNA exposed to short pulses of microwave irradiation were subjected to restriction fragmentation by Eco RI and Bam HI. Eco RI digests of microwaved DNA samples yielded three additional fragments ranging in base pair lengths between 24,226 and 7,421 besides the six expected fragments. While Bam HI digests of the microwaved samples did not yield any additional fragments, mobilities of the Bam HI fragments from the microwaved DNA samples were slower and the bands were broader in comparison to those from native samples. We attribute these altered restriction patterns to the conformational anomolies in DNA resulting from single strand breaks and localized strand separations induced by microwave irradiation.

Molecular cloning and functional expression of alternative oxidase from Candida albicans.

The AOX1 gene, which encodes an alternative oxidase, was isolated from the genomic DNA library of Candida albicans. The gene encodes a polypeptide consisting of 379 amino acids with a calculated molecular mass of 43,975 Da. The aox1/aox1 mutant strain did not show cyanide-resistant respiration under normal conditions but could still induce cyanide-resistant respiration when treated with antimycin A. The measurement of respiratory activity and Western blot analysis suggested the presence of another AOX. When C. albicans AOX1 was expressed in alternative oxidase-deficient Saccharomyces cerevisiae, it could confer cyanide-resistant respiration on S. cerevisiae.

Allergic contact dermatitis from a pyridine derivative in polyvinyl chloride leather.

Antimicrobial coating of household products has gained wide acceptance in Japan in the past several years. Pyridine derivatives, used as antifungal or antibacterial agents in many common products, are known to cause contact dermatitis. We present a case of severe contact dermatitis caused by a pyridine derivative used as an antifungal agent in the polyvinyl chloride (PVC) leather of a chair. An open patch test was performed with each ingredient of the PVC leather. Other products were previously eliminated from consideration based on a series of negative patch tests. The PVC leather obtained from the patient's chair gave a ++ reaction with evident blistering, according to the International Contact Dermatitis Research Group standard. Fifteen ingredients of the PVC leather were open patch tested; a positive reaction was found with 2,3,5,6-tetrachloro-4 (methylsulphonyl) pyridine (1% in petrolatum). Clinicians should be aware that antifungal or antibacterial agents may be increasingly incorporated into common household products and should be suspected in cases of contact dermatitis.

Endometrial carcinoma.

Endometrial cancer is a common tumor of the female genital tract. The majority of women diagnosed with endometrial cancer present with early-stage disease. Although the optimal treatment for these patients requires hysterectomy, the use of lymphadenectomy is controversial. Growing scientific data support the use of lymphadenectomy in all patients diagnosed with endometrial cancer. When performed by an experienced surgeon, pelvic and para-aortic lymphadenectomy is a safe and potentially therapeutic procedure that provides prognostic information to the patient and physician. This information allows appropriate, cost-effective treatment strategies to be created for all women with endometrial cancer.

Deficiency of D-erythroascorbic acid attenuates hyphal growth and virulence of Candida albicans.

In some lower eukaryotes, D-erythroascorbic acid, a five-carbon analog of L-ascorbic acid, is present instead of L-ascorbic acid. We have cloned ALO1, the gene encoding D-arabinono-1,4-lactone oxidase, which catalyzes the final step of D-erythroascorbic acid biosynthesis in Candida albicans. The ALO1 gene contained a continuous open reading frame of 1,671 bp that encodes a polypeptide consisting of 557 amino acids with a calculated molecular mass of 63,428 Da. To investigate the functional roles of D-erythroascorbic acid in C. albicans, we disrupted or overexpressed the ALO1 gene. In the alo1/alo1 null mutants, the activity of D-arabinono-1,4-lactone oxidase was completely lost and D-erythroascorbic acid could not be detected. When ALO1 on a multicopy plasmid was transformed in C. albicans, the enzyme activity and the intracellular D-erythroascorbic acid level were increased up to 3.4-fold and 4.0-fold, respectively. The alo1/alo1 null mutants of C. albicans showed increased sensitivity towards oxidative stress. Overexpression of ALO1 made the cells more resistant to the same stress. The alo1/alo1 mutants showed defective hyphal growth and attenuated virulence. Taken together, our results suggest that D-erythroascorbic acid functions as an important antioxidant and can be considered one of the virulence factors enhancing the pathogenicity of C. albicans.

Confocal laser scanning microscopic observation of glycocalyx production by Staphylococcus aureus in mouse skin: does S. aureus generally produce a biofilm on damaged skin?

BACKGROUND: Bacteria that adhere to damaged tissues encase themselves in a hydrated matrix of polysaccharides, forming a slimy layer known as a biofilm. This is the first report of detection of glycocalyx production by Staphylococcus aureus using confocal laser scanning microscopy (CLSM) on damaged skin tissues. OBJECTIVES: To analyse glycocalyx production by S. aureus cells on damaged skin tissues and the influence of polymorphonuclear leucocytes (PMNs) and various antimicrobial agents on its production using CLSM in cyclophosphamide (Cy)-treated (neutropenic) or non-Cy-treated (normal) mice. METHODS: S. aureus cells were inoculated on damaged skin tissues in neutropenic or normal mice with or without topical application of antimicrobial agents. S. aureus cells were stained with safranine, and positive staining with fluorescein isothiocyanate-conjugated concanavalin A was considered to indicate the presence of glycocalyx. RESULTS: All S. aureus cells tested on damaged skin tissues formed microcolonies encircled by glycocalyx. The colony counts of S. aureus cells on croton oil dermatitis in normal mice treated with 2% fusidic acid ointment were about 100 times lower than those in neutropenic mice (control). CONCLUSIONS: As S. aureus cells can generally produce a biofilm on damaged skin tissues, antimicrobial agents may not eradicate S. aureus cells without the help of PMNs. S. aureus glycocalyx may play a crucial role in colonization and adherence to damaged skin tissues.