Superficial Staining Research Articles

D2-40 and CK17 Immunohistochemistry as a Diagnostic Adjunct for HPV-Independent Squamous Lesions in the Vulva and Their Role in Defining Atypical Lichen Sclerosus.

Vulvar lichen sclerosus (LS) is a common, chronic inflammatory disorder with a subset of cases progressing to differentiated vulvar intraepithelial neoplasia (dVIN) and/or squamous cell carcinoma (SCC). Histopathologic diagnosis of LS and dVIN can be challenging, and it is difficult to predict the subset of LS cases that progress. Immunohistochemistry (IHC) may be a useful diagnostic aid in this setting. CK17 has been shown to be overexpressed in invasive SCC and dVIN, and less commonly in LS. Similar to CK17, D2-40 has been correlated with cutaneous SCC prognosis but has not been evaluated in vulvar lesions. We identified a total of 13 patients with HPV-independent vulvar SCC that had precursor LS or dVIN. CK17 and D2-40 IHC stain intensity and pattern was scored in foci of LS, dVIN, and SCC. An increase in basal layer D2-40 expression was observed with progression from LS to dVIN with strong and diffuse staining in SCC. CK17 maintained similar stain intensity among squamous lesions, but displayed different patterns of staining, with superficial staining in LS, suprabasal staining in dVIN, and diffuse staining in SCC. A subset of LS cases displayed an intermediate (suprabasal) CK17 IHC profile, wild-type p53 expression, and cytomorphologic and architectural features intermediate between LS and dVIN; we defined such cases as "atypical LS." We found that a panel of D2-40/CK17 can serve as a diagnostic adjunct to differentiate LS, dVIN, and invasive SCC. Additional studies with larger patient cohorts are needed to validate these findings and determine their prognostic significance.

Brighten Up Your Smile. Bring out the Natural Whiteness

Aesthetics are often a major concern for young patients with anterior tooth involvement. Patients typically seek dental care to improve their smiles due to irregularities in the enamel and superficial stains. These stains or anomalies in dental hard tissue can be caused by fluorosis, mineralized white patches, hypoplasia, and amelogenesis imperfecta. Different treatment modalities are used to treat these staining of teeth. In the present case report dental fluorosis is treated with MDC Antivet Bleaching agent in anterior teeth and stainless-steel crowns in all four permanent molars in a thirteen-year-old child. The minimal invasive technique was used for bleaching anterior teeth and molars were preserved with full coverage stainless steel crowns. The appearance of the treated enamel showed a surface almost completely free of fluorotic stains, demonstrating the satisfactory results of this treatment.

Image analysis comparison of nerve staining with food dye, methylene blue or tissue marker

ObjectiveNovel locoregional techniques use dye studies to confirm successful nerve targeting. The goal was to objectively quantify and compare nerve staining characteristics of dye mixtures commonly reported in the literature using image analysis software. Study designProspective, randomized cadaveric study. MethodsThirty-six brachial plexus nerves from unpreserved pig cadavers were randomized into three groups of 12: FD (1:10 mixture of blue food dye and bupivacaine 0.5%), MB (methylene blue 1%) and TM (0.1:10 mixture of blue tissue marker and lidocaine 2%). Nerves were immersed in dye for 1, 15, 30 or 60 minutes (n = 3 each). Images of nerves before immersion (baseline) and at each time point with epineurium intact (superficial staining) and after longitudinal bisection (deep staining) were processed using image analysis software. Color saturation values were divided into quartiles (dark, medium-dark, medium-light or light). Percentage of stained nerve area in each quartile was calculated and compared using two-way anova. ResultsSuperficially, at minute 1, dark saturation covered 40% of nerve area in FD versus 19% in MB (p = 0.04) and 0% in TM (p < 0.0001). In bisected nerves, dark and medium-dark saturations occurred only in FD; medium-light saturation comprised anywhere from 4% to 22.5% over time in FD versus <1% at any time in MB (p = 1.000; p = 0.343; p = 0.383; p = 0.262). Deep staining was not found in TM at any point. Conclusion and clinical relevanceFood dye rapidly stains superficial and deep nerve layers. Based on these characteristics, investigators can choose the appropriate dye for their study.

COMPARISON BETWEEN ATRAUMATIC RESTORATIVE TREATMENT AND NON-RESTORATIVE TREATMENT FOR CARIES DISEASE CONTROL

Non-restorative treatment, along with atraumatic restorative treatment (ART) are considered minimally invasive procedures within dentistry. Non-restorative treatment basically consists of preventing, controlling and reversing the carious lesion and atraumatic restorative treatment (ART) in the removal of carious tissue using manual instruments, promoting remineralization of both enamel and dentin. These techniques are considered as an alternative to control fear and anxiety within Pediatric Dentistry, in patients with behavioral problems, in cases of anxious, non-collaborative children or those with systemic impairments. Thus, the present work turns to a literature review with the objective of comparing Atraumatic Restorative Treatment and Non-restorative Treatment within their indications for long-term caries control, describing the materials that are used and methods used. As a result, we observed the effectiveness of fluoride in its various compositions, the ability to prevent carious lesions using Silver Fluoride Diamine, the regression of lesions through the use of casein and the benefit of ART in reducing dental anxiety and patient discomfort. It is concluded that the type of treatment to be chosen depends on the characteristic and degree of the lesion. In the case of superficial stains, the procedure adopted is non-restorative and in the case of dentinal cavities, ART offers good results.

Esthetic treatments for white and yellow/brown enamel stains

In order to solve the dental aesthetic pattern of a patient, who has dental stains on the enamel surface, we carried out this case report where are presented the steps employed for bleaching of teeth with superficial yellow/brown enamel stains with carbamide peroxide and micrometric removal of hard white enamel stains using the enamel microabrasion technique. The worn of dental surface during enamel microabrasion technique was measured with a digital analysis, using a intraoral scanner. It was observed a surprisingly esthetic outcome as the superficial enamel stains were camouflaged by the at-home dental bleaching. Only the superficial white enamel stains that remained evident were removed by enamel microabrasion technique with a minimal average wear of 118 um of the dental enamel on all anterior teeth, showing to be a conservative technique. Dental bleaching can solve the discoloration of vital teeth, such as the superficial yellow/brown hard enamel stains, as well as can mask the superficial white enamel stains. But when necessary, enamel microabrasion technique is an effective minimally-invasive option that can also be adopted.

Efficacy of non-hydrogen peroxide mouthrinses on tooth whitening: An in vitro study.

To evaluate the tooth whitening efficacy of non-hydrogen peroxide containing mouthrinses. Forty incisors were randomly assigned into four groups. Four whitening mouthrinses, Oral-B 3D White Luxe/Procter & Gamble (WL), Listerine Advanced White/Johnson & Johnson (AW), Colgate Max White/Colgate (MW), and iWhite Whitening Mouthwash/Sylphar (iW), were used over a four-week period. Color changes of L*, a*, b*, ΔE*ab , and ΔE00 , were recorded by a digital spectrophotometer (Spectroshade Micro/Mht), at baseline and intermediate week-intervals. Data were statistically analyzed using repeated measures ANOVA at α=0.05. The first-week mean change of L* was 0.76 and significantly different from the baseline for all solutions, without any further changes. Correspondingly, a* decreased by -0.36, while b* increased by 0.48, contributing to a color change of 1.15 ΔE*ab or 0.91 ΔE00 . No differences were found among the solutions in respect to color-parameter changes (p > 0.05). Differences among time intervals were significant (p< 0.05) and mainly observed between the baseline and the following week-measurements. There was no statistically significant time-solution interaction (p > 0.05). Non-hydrogen peroxide whitening mouthrinses, slightly contribute to tooth whitening, by removing superficial staining, without any further tooth bleaching effect. Non-hydrogen peroxide containing whitening mouthrinses, despite having a quick initial action, reach their ceiling relatively soon. Their effectiveness is barely perceptible and definitely inferior to other professional tooth bleaching methods. Thus, they can only be considered as a supplementary way of keeping teeth whiter, mainly by preventing recurrent tooth discoloration.

A Case of Amyloidosis Cutis Dyschromica

The patient was a 56-year-old female. The whole body has brown patches for 16 years. Dermatological examination: brown patches were observed on the trunk and lower limbs, with scattered hypomigmentation patches and symmetrical distribution of skin lesions. Histopathology of the skin showed mild hyperkeratosis in the epidermis, focal liquefaction degeneration in the basal layer, masses of light red stained material in the dermal papilla, scattered or small patches of lymphocytes and tissue cell infiltration around capillaries in the superficial dermis, more pigmentophagocytes and positive methyl violet staining were observed. Diagnosis: cutaneous amyloidosis with abnormal pigmentation. The patient is still being followed up.

Effectiveness of a microabrasion technique using 16% HCL with manual application on fluorotic teeth: A series of studies.

BACKGROUNDDental fluorosis is caused by excessive fluoride ingestion during tooth formation. As a consequence, there is a higher porosity on the enamel surface, which causes an opaque look.AIMThe aim of this study was to identify a dental intervention to improve the smile in patients with tooth fluorosis. Additional aims were to relate the stain size on fluorotic teeth with the effectiveness of stain removal, enamel loss and procedure time using a manual microabrasion technique with 16% hydrochloric acid (HCL).METHODSAn experimental study was carried out on 84 fluorotic teeth in 57 adolescent patients, 33 females and 24 males, with moderate to severe fluorosis. The means, standard deviations and percentages were analyzed using nonparametric statistics and ArchiCAD 15 software was used for the variables including stain size and effectiveness of stain removal.RESULTSThe average enamel loss was 234 µm and was significantly related to the procedure time categorized as 1-4 min and 4.01-6 min, resulting in a P > 0.000. The microabrasion technique using 16% HCL was effective in 90.6% of patients and was applied manually on superficial stains in moderate and severe fluorosis. Procedure time was less than 6 min and enamel loss was within the acceptable range.CONCLUSIONMicroabrasion is a first-line treatment; however, the clinician should measure the average enamel loss to ensure that it is within the approximate range of 250 µm in order to avoid restorative treatment.

GLUT1 expression in human papillomavirus-positive anogenital lesions.

GLUT1, an ubiquitous glucose transporter in the mammalian cells, is upregulated in many tumours, including human papillomavirus (HPV)-induced head and neck or cervical cancer. To study in anogenital lesions whether or not GLUT1 expression correlates with genomic high-risk HPV integration, the first step in neoplastic transformation. Forty-three HPV-positive biopsies positive for either low-risk or high-risk HPV were selected. Paraffin sections adjacent to those tested for the presence of HPV were processed for GLUT1 immunocytochemistry. GLUT1 expression was analysed by two histologists, blinded to HPV type and status and then compared with HPV typing results. Two main staining patterns were observed, either staining from the basal to the granular layer or staining of superficial layers only. The first staining pattern corresponded to lesions with high number of episomal HPV-positive nuclei. Superficial staining was observed in lesions with low number of episomal HPV nuclei or when high-risk HPV was integrated in the cell genome. Our results show that GLUT1 overexpression correlates with the number of episomally infected cells in the lesion, but not with the type (low or high risk) of HPV.

Influence of different application protocols of universal adhesive system on the clinical behavior of Class I and II restorations of composite resin \u2013 a randomized and double-blind controlled clinical trial

BackgroundMultimode adhesives incorporate the versatility of adapting to various clinical situations by its capacity to be used in different protocols. This study aimed to evaluate the clinical behavior of composite resin direct restorations (Class I and II) performed with different universal dentin adhesive application protocols comparing adapted FDI and adapted USPHS criteria.MethodsThe current study is a randomized, double-blind, split-mouth, and convenience sample controlled clinical trial. The participants (age ≥ 18 years) had restorative need of Class I and/or II due to the presence of carious lesions and/or unsatisfactory restorations in at least three dental elements. Each participant received three application protocols for Scotchbond Universal adhesive (3M ESPE), one in each tooth to be restored: ER = etch-and-rinse + adhesive (n = 50); SEE = selective enamel etch + adhesive (n = 50) and SE = self-etch adhesive (n = 50). All teeth were restored in a similar way using Filtek™ Supreme composite resin (3M ESPE). Restorations were evaluated using the adapted FDI and adapted USPHS criteria, at baseline after 7 to 21 (12.02 ± 5.68) days (T1; n = 50 per group) and after 12 to 20 (15.8 ± 2.7) months (T2; n = 46 per group) by two previously calibrated evaluators (Kappa > 0.80). The statistical tests were performed between groups (Friedman), intragroup (Wilcoxon), and between the criteria considering acceptable and not acceptable restorations (McNemar), α = 0.05.ResultsA statistically significant difference was observed only for the property “superficial staining”, between groups at T2 (p = 0.01) for ER (n = 13 with score 2 or more) and SEE (n = 3 with score 2 or more) and intragroup for ER (T1, n = 1 with score 2 or more; T2, n = 13 with score 2 or more, p = 0.001) and SE (T1, n = 0 with score 2 or more; T2, n = 8 with score 2 or more p = 0.007). For the other comparisons between groups, intragroup, and between the adapted FDI and adapted USPHS criteria, there were no statistically significant differences (p ≥ 0.05).ConclusionsIt can be concluded that the different application protocols of the universal adhesive resulted in clinically “acceptable” restorations after 15.8 ± 2.7 months of follow-up. Adapted FDI and adapted USPHS criteria provided similar results to each other.Trial registration.Number in Brazilian Registry of Clinical Trials (ReBEC): RBR-9p3hdp. Registered 24 May 2015.

Anatomic variability of the intercostal neurovascular bundle in human fetuses.

Background. Studying the features of fetal topography of the intercostal neurovascular bundle in fetuses of different ages allows establishing general biological patterns of morphogenesis, typical structure and topography of structures of intercostal spaces, age and individual anatomical variability of intercostals nerves and posterior intercostals vessels. Objective – to clarify the peculiarities of the topography of the intercostals neurovascular bundle components in human fetuses aged 4-10 months. Methods. The study involved 70 specimens of human fetuses with 81.0-375.0 mm of crown-rump length by macro-microscopic dissection, injection of blood vessels, superficial staining of the dissected vessels and nerves as well as morphometry. Results. During the fetal period of ontogeny, there is an age and individual anatomical variability of intercostals neurovascular bundles, which is manifested by variability of structure, topography and number of their constituents, asymmetry of topography of right and left posterior intercostals vessels and nerves, different branching of the posterior intercostals arteries and nerves, by a variety of the development of the system of the azygos vein and its tributaries, both in fetuses of different and of the same age group or even in the same fetus. Conclusions. The trunks of adjacent intercostals nerves and posterior intercostals vessels are connected by means of connecting branches. Therefore, during operations on the lateral chest wall, one should be mindful of anastomoses between the vessels and nerves of adjacent intercostals spaces that realize the effect of cross-vascularization and innervations of the structures of the chest wall. Besides, connecting branches go from the nodes of the thoracic section of the sympathetic trunk to the intercostals nerves. The variants of the topography and branching of the intercostals nerves and posterior intercostals arteries in the intercostals spaces and the peculiarities of out flow of venous blood from their posterior areas should be taken into account by fetal and neonatal surgeons during surgery.

Randomized Prospective Clinical Trial of Class II Restorations Using Low-shrinkage Flowable Resin Composite.

The aim of this prospective, randomized, split-mouth clinical trial was to evaluate postoperative sensitivity, clinical performance, and interproximal contacts after using different restorative systems. Fifty-three subjects each received three class II restorations according to the restorative systems: conventional resin composite (PA: Peak Universal+Amelogen Plus, Ultradent), low-shrinkage flowable and nanoparticulate resin composites (ABF: Adper Single Bond 2+Filtek Bulk Fill Flow+Filtek Z350XT, 3M ESPE), and low-shrinkage flowable and microhybrid resin composites (XST: XP Bond+SDR+TPH3, Dentsply). Postoperative sensitivity was assessed at 24 hours, seven days, 90 days, and six months. The clinical performance and interproximal contacts were evaluated at baseline, six months, and one year. Friedman, Wilcoxon, Kruskal-Wallis, and Mann-Whitney tests were used to evaluate postoperative sensitivity and interproximal contacts. The equality test of two proportions and logistic regression analysis were used to assess the clinical performance. No statistically significant differences were observed among groups for postoperative sensitivity. The highest spontaneous sensitivity was reported at 24 hours. ABF was the only group that did not present a reduction in cold sensitivity. Color, marginal discoloration, and superficial staining showed differences among the groups. XST did not show superficial staining after one year. No differences were observed among groups in relation to interproximal contacts. XST resulted in the loss of interproximal contact after one year. Different types of restorative systems do not influence postoperative sensitivity; however, ABF maintained cold sensitivity over time. Marginal discoloration occurred for all groups but occurred earliest for PA. XST presented a reduction of interproximal contact after one year of evaluation.

Medicaments and oral healthcare 5. Adverse effects of -medications and over-the-counter drugs on teeth

Intrinsic tooth discoloration may occur as an adverse effect of fluoride and tetracyclines. Extrinsic tooth discoloration may occur as superficial staining or as discoloration of the superficial pellicle and/or biofilm due to chlorhexidine, liquid iron salts, essential oils, some antibiotics and stannous fluoride. Inhibition of orthodontic tooth movement has been reported due to the use of prostaglandin synthetase inhibitors. If medications or over-the-counter drugs induce hyposalivation or contain much sucrose, caries may develop. Erosion may occur if the acidity of medications or over-the-counter drugs is excessive. Attrition is a well-known adverse effect of serotonin reuptake inhibitors, antiparkinson agents, and antipsychotics. Congenital dysplasia is observed following childhood treatment with cytostatic drugs. External cervical root resorption is an adverse effect of internal teeth-whitening products. Prenatal exposure to antiepileptic drugs and childhood treatment with cytostatic drugs may cause dental agenesis. Antiseptic drugs applied for external teeth-whitening and toothpastes with additional ingredients to prevent extrinsic discoloration and creation of calculus, may cause tooth hypersensitivity.

Clinical evaluation of aqueous outflow system in vivo and correlation with intraocular pressure before and after non-penetrating glaucoma surgery.

The aim of this study was to evaluate the aqueous outflow system through channelography with fluorescein during non-penetrating glaucoma surgery (canaloplasty or phacocanaloplasty) and find correlations with preoperative and postoperative intraocular pressure (IOP). Thirty-six patients (40 eyes) who had channelography while undergoing non-penetrating glaucoma surgery were included in this prospective study. Several parameters assessed during the channelography included: diffuse and superficial scleral staining, the number of visible superficial connections to collectors, trabecular permeability and number of micro-ruptures of the trabecular meshwork. IOP, the best-corrected visual acuity, the number of glaucoma medications was recorded at 1day, 7days, 3months and 6months after the operation. The change in IOP at 6months from baseline significantly correlated with the number of visible superficial connections to collectors (r=0.4, p=0.021). Eyes with canaloplasty showed a mean baseline IOP of 19.4 (4.9)mmHg and mean glaucoma medication usage of 2.9 (1.0), which decreased to 13.2 (3.1)mmHg with 0.3 (0.8) medications, respectively, at 6months postoperatively (p<0.001). Eyes with phacocanaloplasty surgery showed a mean baseline IOP of 28.2 (9.6)mmHg with 2.6 (0.9) mean drugs, which decreased to IOP of 12.8 (3.4)mmHg with 0.5 (0.8) medications at 6months (p<0.001). A larger number of defined visible superficial connections to collectors after injection of fluorescein into SC is related to a more pronounced IOP decrease after non-penetrating glaucoma surgery.

Enamel microabrasion: An overview of clinical and scientific considerations.

Superficial stains and irregularities of the enamel are generally what prompt patients to seek dental intervention to improve their smile. These stains or defects may be due to hypoplasia, amelogenesis imperfecta, mineralized white spots, or fluorosis, for which enamel microabrasion is primarily indicated. Enamel microabrasion involves the use of acidic and abrasive agents, such as with 37% phosphoric acid and pumice or 6% hydrochloric acid and silica, applied to the altered enamel surface with mechanical pressure from a rubber cup coupled to a rotatory mandrel of a low-rotation micromotor. If necessary, this treatment can be safely combined with bleaching for better esthetic results. Recent studies show that microabrasion is a conservative treatment when the enamel wear is minimal and clinically imperceptible. The most important factor contributing to the success of enamel microabrasion is the depth of the defect, as deeper, opaque stains, such as those resulting from hypoplasia, cannot be resolved with microabrasion, and require a restorative approach. Surface enamel alterations that result from microabrasion, such as roughness and microhardness, are easily restored by saliva. Clinical studies support the efficacy and longevity of this safe and minimally invasive treatment. The present article presents the clinical and scientific aspects concerning the microabrasion technique, and discusses the indications for and effects of the treatment, including recent works describing microscopic and clinical evaluations.

Effect of finishing and polishing procedures on biofilm adhesion to composite surfaces: An ex vivo study

Introduction: Surface roughness allows plaque accumulation resulting in gingival inflammation, superficial staining and secondary caries. Proper surface finishing and polishing are critical clinical procedures which enhance esthetics and longevity of restorations. This study evaluated adhesion of Streptococcus mutans biofilm on the surface of composite resin discs (nanofilled, Filtek Z350, 3M ESPE, Salt Lake City, UT, USA) after finishing and polishing by different techniques. Methodology: Sixty samples of nanofilled composite resin were prepared in a circular shaped disc- 6 mm × 2 mm and divided randomly in three groups (n = 20) for surface treatments. Control group: composite resin surface in contact with Mylar matrix strips with no finishing or polishing performed, Sof-Lex aluminum oxide disc technique and 30-blade tungsten carbide burs and silicon carbide brushes, Astrobrush. The samples were subjected to biofilm adhesion by inoculation in suitable media. The response variable was the mean CFU/mL present in the Streptococcus mutans biofilms formed on the composite resin surface. Data was statistically analyzed by three-way analysis of variance (ANOVA). Results: The Mean adhesion found in Mylar matrix strip group at 10 dilution was 74.7 ± 3.5, in Sof-Lex group was 147.3 ± 7.0 and in Astrobrush group was 149.4 ± 8.1. This difference in the mean values between the groups was found to be statistically significant (p < 0.01). Conclusion: Mylar matrix strips promoted the least bacterial adhesion, polishing with Sof-Lex aluminium oxide discs provided a smoother surface than Astrobrush and hence less bacterial adhesion than Astrobrush system.

Gently remove superficial stains

Gently remove superficial stains

Evaluation of the physicochemical, physical and sensory properties of fresh cape gooseberry and vacuum impregnated with physiologically active components

Background: Functional Foods are considered nowadays by consumers as the range of foods of major interest. Objectives: The aim of the present work was the evaluation of color, texture and sensorial properties of fresh Cape Gooseberry (FG) and vacuum impregnated Cape Gooseberry (IG) with calcium and vitamins B9, C, D and E during storage at 4ºC. Methods: Entire cape gooseberries were vacuum impregnated (VI) with tocopherol and cholecalciferol emulsified in aqueous phase with sucrose, ascorbic acid, folic acid, calcium chloride, calcium fumarate, low methoxyl pectin, isolated soy protein, tensoactives and preservatives. The texture was determined from puncture assays, and the color from the CIE Lab coordinates. The sensorial profile was determined with the aid of trained panelists, through a multidimensional approach of characteristic descriptors of general appearance, odor, taste and texture. Results: The instrumental values of color and texture for IG were significantly different from the FG, because are being softer, more elastic, darker, brighter and of less color saturation. The samples of FG and IG presented intense sensorial characteristics in the descriptors orange color, brightness, spherical uniformity, smooth surface, fresh appearance, odor, cape gooseberry characteristic taste and frutal, fleshy texture, juicy, firmness and turgidity. By the effect of VI process the most relevant significant differences were the descriptors orange color, superficial stains, fresh appearance, sweet taste and cape gooseberry characteristic taste, soft texture, firmness and juicy; whereas for the effect of storage time were fresh appearance, dehydrated appearance, peduncle cicatrization, aromatic odor, overripe, cape gooseberry characteristic taste, frutal taste, soft texture, juicy, firmness and turgidity. Conclusions: The VI significantly affects the objective&#x0D; assessment of color and texture, finding correspondence with the sensorial evaluation; nonetheless, the general quality of the FG presented a greater score than those presented by IG.

Mechanisms of superficial micropunctate corneal staining with sodium fluorescein: The contribution of pooling

To establish if sodium fluorescein (SFL) dye accumulation within intercellular spaces on the ocular surface contributes to the appearance of superficial punctate corneal staining. Thirteen subjects bilaterally wore PureVision™ lenses that had been pre-soaked in ReNu MultiPlus® multipurpose solution. After 1h of lens wear, corneal staining with SFL was assessed using a standard slit-lamp technique. Participants who presented with bilateral, corneal staining were selected for further evaluation. A randomly selected eye was rinsed with saline three times. Fellow eyes (control) received no rinsing. After each rinse, the appearance of SFL staining was recorded without any further instillation of the dye. To eliminate any confounding effects of staining due to residual fluorescein in the tear menisci, corneal staining was induced in freshly excised, isolated, rabbit eyes by topical administration of 0.001% PHMB and staining, rinsing and grading were performed as above. Nine out of 13 subjects presented with bilateral diffuse corneal staining (mean grade±SD: 2.4±0.7). The mean staining grades in test and control eyes respectively after each of the three rinses were (1) 2.41±0.41, 2.25±0.69 (p=0.9); (2) 2.34±0.79, 2.1±0.83 (p=0.8); and (3) 1.71±0.65, 1.60±0.79 (p=0.6) there was no significant reduction in staining with rinsing (p>0.05) and no difference was observed between test and control eyes at any sampling-point. Similar observations made in ex vivo rabbit eyes replicated these results. Pooling or accumulation of SFL solution within intercellular spaces does not appear to contribute to the appearance of superficial micropunctate corneal staining.

Immunization of Mice with Lactobacillus casei Expressing a Beta-Intimin Fragment Reduces Intestinal Colonization by Citrobacter rodentium

Enteropathogenic Escherichia coli (EPEC) is a common cause of diarrhea in children from developing countries. Intimate adhesion of the bacteria to intestinal cells occurs via binding of the adhesin intimin to the TIR receptor exposed on cell surfaces. Here, Lactobacillus casei expressing a fragment of β-intimin (L. casei-Int(cv)) was tested as mucosal vaccines in mice against intestinal colonization with the murine pathogen Citrobacter rodentium. Oral or sublingual immunization of C57BL/6 mice with L. casei-Int(cv) induced anti-Int(cv) IgA in feces but no IgG in sera. Conversely, anti-Int(cv) IgG was induced in the sera of mice after sublingual immunization with purified Int(cv). All vaccines were able to decrease C. rodentium recovery from feces. However, this reduction was more evident and sustained over time in mice immunized with L. casei-Int(cv) by the sublingual route. These mice also displayed an increase in interleukin 6 (IL-6) and gamma interferon (IFN-γ) secretion by spleen cells 10 days after infection. Additionally, oral or sublingual immunization of C3H/HePas mice, which are highly susceptible to C. rodentium infection, with L. casei-Int(cv) induced anti-Int(cv) antibodies and significantly increased survival after challenge. Immunohistological analysis of colon sections revealed that C. rodentium was located in deep fractions of the tissue from C3H/HePas mice immunized with L. casei whereas superficial staining was observed in colon sections from mice immunized with L. casei-Int(cv.) The results indicate that vaccines composed of L. casei expressing intimin may represent a promising approach and that the C3H/HePas infection model with C. rodentium can be used to evaluate potential vaccines against EPEC.