Tear Strips Research Articles

Assessment of Salivary Flow Rate and Salivary PH in Subjects with Smoked, Smokeless, and Combined form of Tobacco Habits (Epidemiological-Based Study)

Abstract Background: Saliva is a complicated secretion of the oral cavity and is the first fluid to be exposed to the toxic components of tobacco products. Saliva undergoes structural and functional changes due to tobacco use throughout time. As a result, measurements of salivary flow rate (SFR) and pH were made in subjects with habit of smokeless, smoked, and combined forms of tobacco habits. Methodology: The study was conducted in a dental institute. Subjects with the habit of smoking, smokeless, and combined forms of habits were included in this study. Schirmer tear strips and pH strips were used to assess SFR and pH. Results: On comparison of SFR between control and habit groups, a statistically significant reduction of SFR was observed in habit groups. On comparison of salivary pH, a statistically significant decrease was observed in smokeless and smoked form of tobacco usage group when compared with the control group. Duration, frequency, and exposure also alter SFR and pH. Significant gradual decline in resting salivary flow rate levels with increase in duration of tobacco usage and increase in number of packs consumed/day was observed. Conclusion: The role of salivary flow and pH is to maintain oral and dental health. Based on the results of this study, we concluded that long-term habits, whether smokeless, smoking, or combined tobacco habit, significantly reduce SFR and pH. These alterations can render oral mucosa more vulnerable to various oral diseases.

Usefulness of Schirmer's tear strips and borosilicate glass tubes in chemical analysis of human tear fluid: A practical check in VEGF detection.

Human tears contain a number of agents which may play an important role in diagnosing local eye disorders as well as systemic diseases. The small amount of fluid obtained during the collection and the consequent difficulty in analysing it are the main problems encountered in the diagnostic process. We decided to investigate the practical usefulness of two simple methods of collecting tear fluid for chemical analysis, i.e., glass tubes and Schirmer's strips. The substance analyzed was vascular endothelial growth factor (VEGF), a compound commonly recognized in ophthalmology. We used standard Schirmer's tear test and calibrated glass tubes for tear fluid collection in healthy volunteers. The standard ELISA assay was used to check the effectiveness of the tear sampling by estimating the VEGF level. The results of the study show that Schirmer's tear strip test is a more effective tool of the two. Moreover, using Schirmer's strips to obtain tear fluid was found to be more patient friendly and amounts of the tear fluid collected with that test were enough and better for the VEGF detection. Our study indicates that the widely used Schirmer tear test may be the best method of tear collection for chemical analysis. However, further studies on test calibration are needed.

Tear Fluid as a Biomarker for Parkinson’s Disease: Downregulation of DNA Repair Genes/Pathways via RNA-Seq Analysis (S37.007)

<h3>Objective:</h3> We performed an RNA-Seq analysis of tears from 16 Parkinson’s Disease (PD) patients and 16 healthy, age-matched healthy controls (HC) to identify genes and pathways that may serve as biomarkers of PD. <h3>Background:</h3> We previously demonstrated that PD tears have significantly higher levels of oligomeric a-synuclein than HC tears. Analyses of hundreds of subjects demonstrated this biomarker predicted PD diagnosis, irrespective of disease duration (AUROC=0.76). To improve this model, we performed RNA-Seq on PD and HC tears. Pilot studies of brain and tears revealed ~74% of genes expressed in aged cortex were expressed in tears. <h3>Design/Methods:</h3> Schirmer’s Tear Strips were frozen at −80°C. RNA was extracted and evaluated for quantity and integrity (RIN). RNA-Seq libraries were prepared with the NEBNext Ultra II RNA Library Prep Kit and sequenced on an Illumina NovaSeq sequencer. FASTQ files were aligned with Tophat and transcripts were counted and compared with Cufflinks. Pathway analysis was performed using the Qiagen Ingenuity Pathway Analysis (IPA) software and unsupervised, hierarchical clustering of significantly affected pathways was tested with RStudio. <h3>Results:</h3> RNA-Seq analysis showed more genes were downregulated in PD tears (N=898) vs. upregulated (N=238). IPA analysis of downregulated genes revealed DNA repair pathways were significantly affected, and reflected the downregulation of 60 genes related to DNA excision repair, recombination, and damage in PD tears. These 60 genes included <i>HNRNPC</i>, <i>TARDBP</i>, <i>USP47</i>, <i>EZH2</i>, <i>FANCC.</i> Unsupervised hierarchical clustering of these 60 genes’ transcript levels (FPKMs) separated PD and HC with 83.9% accuracy (sensitivity 93.3% and specificity 75%). <h3>Conclusions:</h3> RNA-Seq may provide a useful strategy for PD diagnosis using tears, a non-invasive biofluid. Preliminary data suggests increased diagnostic accuracy compared to our tear investigations of oligomeric a-synuclein levels alone. Downregulation of DNA repair genes/pathways suggests that alterations observed in PD brains and dopaminergic neurons are also observed in tears <b>Disclosure:</b> Dr. Lew has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for Supernus. Dr. Lew has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for kyowa. Dr. Lew has received personal compensation in the range of $5,000-$9,999 for serving as a Consultant for neurocrine. Dr. Lew has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Acorda. Dr. Lew has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Acadia. Dr. Lew has received personal compensation in the range of $500-$4,999 for serving as a Consultant for RegenXBio. Dr. Lew has received personal compensation in the range of $10,000-$49,999 for serving on a Speakers Bureau for Neurocrine. Dr. Lew has received personal compensation in the range of $5,000-$9,999 for serving on a Speakers Bureau for Kyowa. Dr. Lew has received personal compensation in the range of $500-$4,999 for serving on a Speakers Bureau for acorda. The institution of Dr. Lew has received research support from MJFF. Dr. Lew has received research support from NIH. Miss Omidsalar has nothing to disclose. Miss Singh Kakan has nothing to disclose. Mr. Gerke has nothing to disclose. Ms. Tanveer has nothing to disclose. Dr. Feigenbaum has nothing to disclose. Dr. Tamadonfar has nothing to disclose. Sarah Hamm-Alvarez has received personal compensation in the range of $500-$4,999 for serving as a Consultant for Oyster Point. The institution of Sarah Hamm-Alvarez has received research support from Oyster Point. Dr. Hjelm has nothing to disclose.

Tear levels of IL-7, IL-1α, and IL-1β may differentiate between IgG4-related disease and Sjögren's syndrome.

We aim to assess and compare a cytokine and chemokine profile in tears from patients with IgG4-related disease (IgG4-RD) and Sjögren's syndrome (SS), and to see if this profile could aid in differentiating these two diseases. We included 10 patients with IgG4-RD who met the Comprehensive Diagnostic Criteria for IgG4-RD and 17 patients who met the AECG criteria for primary SS. The Schirmer-I test was carried out using two standardized sterile tear strips, which were then immediately frozen at - 86°C until assayed. The tears were extracted from the strips after they had been defrosted using a buffer containing 0.5M NaCl and 0.5% Tween-20. The amounts (pg/ml) of the following cytokines and chemokines were then measured using luminometry: IFN-γ, TNF-α, G-CSF, IL-1-α, IL-1β, IL-4, IL-7, IL-12p40, IL-12p70, IL-13, IL-17A, CCL2, CCL3, CCL4, CCL11, and CXCL10. In the IgG4-RD group, seven patients had lacrimal gland involvement, five had dry eye symptoms, and six had a positive Schirmer-I test. In the SS group, 16 (94.1%) had dry eyes and all had a positive Schirmer-I test. We were able to differentiate between both diseases using levels of IL-7, IL-1α, and IL-1β; in particular, the IL-7/IL-1α and IL-7/IL-1β ratios had the best discriminatory potential, with cut-off values of 0.32 (AUC: 0.93, sensitivity: 94%, specificity: 80%, p = 0.0003) and 12.55 (AUC: 0.96, sensitivity: 94%, specificity: 90%, p = 0.0001), respectively. Our results suggest that IL-7, IL-1α, and IL-1β tear levels could help differentiate IgG4-RD from SS. Key Points • The lacrimal gland is frequently involved in IgG4-RD and SS. This characteristic makes both diseases mimics of one another. • Patients with IgG4-RD and SS have different profiles of tear cytokines and chemokines. • Tear IL-7, IL-1α, and IL-1β levels may serve as helpful biomarkers in separating IgG4-RD from SS.

Analysis and comparison of tear protein profiles in dogs using different tear collection methods

BackgroundTear proteomic analysis has become an important tool in medical and veterinary research. The tear collection method could influence the tear protein profile. This study aims to evaluate the protein profiles of dog tears collected using microcapillary tubes (MT), Schirmer tear strips (ST), and ophthalmic sponges (OS).MethodsThe tear samples were collected using MT, ST, and OS. Tear protein profiles were analyzed using two-dimensional electrophoresis (2-DE) and the different protein spots’ expression was compared. Fourteen protein spots were identified using liquid chromatography-tandem mass spectrometry (LC-MS/MS).ResultsTear protein concentrations ranged from 2.80 to 4.03 μg/μL, with no statistically significant differences among collection methods. Protein expression in each collection method differed in terms of both the number and intensity of the spots. There were 249, 327, and 330 protein spots found from tears collected with MT, ST, and OS, respectively. The proteins albumin, haptoglobin, and lactoferrin identified from OS were found to have higher spot intensities than other methods of collection. The use of MT demonstrated the downregulation of nine proteins.ConclusionsThe recent study supported that tear protein analysis is affected by different tear collection methods. Although ST is commonly used for tear collection, it provides insufficient information to study particular tear proteins.

High-throughput proteomic sample preparation using pressure cycling technology.

High-throughput lysis and proteolytic digestion of biopsy-level tissue specimens is a major bottleneck for clinical proteomics. Here we describe a detailed protocol of pressure cycling technology (PCT)-assisted sample preparation for proteomic analysis of biopsy tissues. A piece of fresh frozen or formalin-fixed paraffin-embedded tissue weighing ~0.1–2 mg is placed in a 150 μL pressure-resistant tube called a PCT-MicroTube with proper lysis buffer. After closing with a PCT-MicroPestle, a batch of 16 PCT-MicroTubes are placed in a Barocycler, which imposes oscillating pressure to the samples from one atmosphere to up to ~3,000 times atmospheric pressure. The pressure cycling schemes are optimized for tissue lysis and protein digestion, and can be programmed in the Barocycler to allow reproducible, robust and efficient protein extraction and proteolysis digestion for mass spectrometry-based proteomics. This method allows effective preparation of not only fresh frozen and formalin-fixed paraffin-embedded tissue, but also cells, feces and tear strips. It takes ~3 h to process 16 samples in one batch. The resulting peptides can be analyzed by various mass spectrometry-based proteomics methods. We demonstrate the applications of this protocol with mouse kidney tissue and eight types of human tumors.

Cadaveric study to assess the feasibility of S1 neurectomy and contralateral S1 transfer for spastic hemiparesis

PurposeAcquired brain injury causing spasticity, pain and loss of function is a major cause of disability and lower quality of life. Sacral 1 (S1) neurectomy claims promising outcomes in spastic hemiparesis. This cadaveric study was conducted to study the surgical anatomy, surgical approach and feasibility of S1 neurectomy and contralateral S1 (cS1) transfer. MethodsThis study was conducted over a period of 10 months and 10 cadavers (age 18–60 years, 7 male and 3 female) were included in the study. 2 cadavers underwent endoscopic S1 neurectomy and 8 cadavers underwent open S1 neurectomy. Mean S1 root length and diameter were recorded using Schirmer tear strips and Vernier calliper. Feasibility of transfer was also assessed by measuring the length of donor nerve and distance between distal ends to proximal end of recipient nerve. ResultsMean thickness of right S1 root was 4.02 ± 1.5 mm and left S1 was 3.89 ± 1.18 mm. Mean length of right S1 root was 24.9 ± 4.56 mm and left S1 was 23.6 ± 2.86 mm. Endoscopically dissected length of S1 was much less as compared to open technique. ConclusionS1 neurectomy is simple procedure to reduce spasticity in lower limb without any permanent deficit. It can be done by open as well as with endoscopic approach while for contralateral S1 transfer open approach need to be used.

Effect of Mobile Phone Radiation on Parotid and Submandibular Salivary GlandsAn Ultrasonographic Study

Introduction: In this era of digitalism, mobile phones have become a cultural accessory. Frequent smartphone usage results in possible adverse effects from low radiofrequency radiation and thermal effect emitted by these devices. One of the major concerns is salivary glands as the mobile phones are held against the side of face in close proximity to these glands. Aim: To assess the effect of cell phone radiation on the volume, systolic velocity, salivary flow rate of parotid and submandibular gland between the dominant and non dominant side of mobile phone users. Materials and Methods: A cross-sectional study was conducted in the Department of Oral Medicine and Radiology with the sample size of 100 (50 males and 50 females). Inclusion criteria were based on the frequency of mobile phone usage of more than two hours per day. Mobile phone usage was determined based on patient’s answer to the questionnaire. Ultrasonography (USG) of both parotid and submandibular gland was done bilaterally to measure the volume of the glands and Colour Doppler of external carotid artery to measure systolic velocity. Modified Schirmer tear strips were used bilaterally to measure unstimulated salivary flow rate. The data was entered into MS excel and significance was calculated using independent sample t-test. Results: In parotid gland, mean volume, mean systolic velocity and mean salivary flow rate were of higher value in the dominant side (14.22±2.17 mL; 15.14±3.74 cm/s; 0.37±0.26 mm/5 mins) compared to the non dominant side (13.76±2.14 mL; 14.53±3.39 cm/s; 0.24±0.2 mm/5 mins). In submandibular gland, mean volume, mean systolic velocity and mean salivary flow rate were of higher value in the dominant side (9.60±1.96 mL; 15.70±6.44 cm/s; 0.30±0.22 mm/5 mins) compared to the non dominant side (8.88±2.17 mL; 13.87±4.83 cm/s; 0.26±0.21 mm/5 mins). Conclusion: The volume, systolic velocity of blood flow, the salivary flow rate, of the parotid gland and submandibular gland were significantly more on the dominant side than the non dominant side of mobile phone usage. The study emphasised that prolonged mobile phone usage causes biological changes in salivary glands and its flow rate.

Tear fluid collection methods: Review of current techniques

Tear fluid, composed of lipid, aqueous, and mucin layers, contains electrolytes, water, proteins, peptides, and glycoproteins. Its components may serve as diagnostic indicators of local and systemic diseases. The aim of the study was to conduct literature review in order to identify the current methods of tear collection. The most commonly used method which was relatively easy to perform and allowed to obtain sufficient tear volume for further chemical and physical analysis was selected through PubMed database search for the following keywords: tear sampling, human tears, chemical analysis of tears, physical tear analysis, animal tear sampling. Final criteria of articles selection were: human tears, tear sample collection, chemical and physical analysis of tears. Time of publication of the articles not older than 1995. The analysis of 70 articles revealed that the most common tear fluid collection methods are Schirmer tear strips and capillary tubes. Thus, we recommend the use of Schirmer strips and microcapillary tubes as the cheapest and easiest methods for sampling of tear fluid for further chemical analysis.

A LC-MS/MS validated method for determination of azithromycin in human tears and its application to an ocular pharmacokinetic study.

A rapid and sensitive method for the quantitative analysis of azithromycin in human tears by LC-MS/MS was developed and validated. Following extraction from collected Schirmer tear strips by methanol-water (4:1, v/v), the analyte and IS (azithromycin-d3) were separated on a Waters Atlantis™ dC18 column (2.1 mm × 30 mm, 3 μm) by gradient elution with 0.1% (v/v) formic acid in methanol-water (1:9) and methanol-acetonitrile (9:1) as the mobile phase. Electrospray ionization in positive ion mode and MRM were used to monitor the ion transitions at m/z 749.6 → 591.6 (azithromycin) and 752.4 → 594.4 (azithromycin-d3). The results indicated that the method had excellent sensitivity and specificity. The analyte appeared to have good linearity in the range of 5-1000 ng/ mL. Both the intra-batch and inter-batch precisions (in terms of RSD) were <10%, and the accuracies (in terms of RE) were within ±15%. The lower limit of quantification, matrix effect, extraction recovery, stability and dilution integrity were also evaluated and satisfied the validation criteria. Artificial tears served as the surrogate matrix, and no matrix difference was found when compared with that of real human tears. Finally, this method was successfully applied in an ocular pharmacokinetic study in healthy volunteers following instillation of azithromycin eyedrops.

An eye on the dog as the scientist's best friend for translational research in ophthalmology: Focus on the ocular surface.

Preclinical animal studies provide valuable opportunities to better understand human diseases and contribute to major advances in medicine. This review provides a comprehensive overview of ocular parameters in humans and selected animals, with a focus on the ocular surface, detailing species differences in ocular surface anatomy, physiology, tear film dynamics and tear film composition. We describe major pitfalls that tremendously limit the translational potential of traditional laboratory animals (i.e.,rabbits, mice, and rats) in ophthalmic research, and highlight the benefits of integrating companion dogs with clinical analogues to human diseases into preclinical pharmacology studies. This One Health approach can help accelerate and improve the framework in which ophthalmic research is translated to the human clinic. Studies can be conducted in canine subjects with naturally occurring or noninvasively induced ocular surface disorders (e.g., dry eye disease, conjunctivitis), reviewed herein, and tear fluid can be easily retrieved from canine eyes for various bioanalytical purposes. In this review, we discuss common tear collection methods, including capillary tubes and Schirmer tear strips, and provide guidelines for tear sampling and extraction to improve the reliability of analyte quantification (drugs, proteins, others).

Tear film concentrations of topically applied 0.5% oxytetracycline ointment in normal canine eyes.

To determine the tear film levels of oxytetracycline in normal canine eyes after application of the ophthalmic ointment, Terramycin™ (0.5% oxytetracycline, polymyxin B sulfate), to guide appropriate treatment frequency. Ten research beagles. Ten research beagles with confirmed normal eyes were administered 0.02mL of Terramycin™ ophthalmic ointment onto the dorsal bulbar conjunctival surface of the right eye. Tear samples were collected via dye-less Schirmer tear strips at 2, 4, 6, 8, and 12hours post-administration. The sample for each timepoint was collected on a separate day, and concentrations of oxytetracycline were determined using high-performance liquid chromatography (HPLC). There was a semi-logarithmic decline in the median tear concentration of oxytetracycline. The median (2.5th and 97.5th percentiles) tear concentrations of oxytetracycline at 2, 4, 6, 8, and 12hours were 43.5μg/mL (11.1-302.2μg/mL), 28.7μg/mL (8.04-113.7μg/mL), 16.1μg/mL (4.96-37.7μg/mL), 9.2μg/mL (4.52-28.1μg/mL), and 6.11μg/mL (4.36-26.7μg/mL), respectively. Mean (±SD) drug recovery via HPLC was 88% (±7.5%). Ophthalmic Terramycin™ achieves a substantially higher tear level than the MIC for common bacterial corneal pathogens up to 12hours post-administration in normal eyes. Anti-collagenolytic tear levels were not achieved at the timepoints evaluated or with the manufacturer-prescribed dosing frequency. HPLC can be used to analyze tear concentrations of ophthalmic ointment formulations.

Aquaporin 1 (AQP1) Expression in Healthy Dog Tears

Simple SummaryThe characterisation of tear proteins is very important for scientists and clinicians, as it enhances their understanding of ocular physiological phenomena that sometimes evolve into diseases. Recently, ophthalmic research has been focused on aquaporins (AQPs), a family of water channel proteins that are largely ubiquitous in body tissues and are known for their role in water and small solute transport across cell membranes. Based on AQPs’ presumable role in the eye, the aim of the present study was to investigate the expression of aquaporin-1 (AQP1) by Western blot analysis in canine eye tears. To this end, we collected tears from both eyes of 15 healthy dogs by employing two tear collection methods: Schirmer tear strips (STS) and ophthalmic sponges (OS). Moreover, ocular parameters such as Schirmer tear test 1 (STT 1), intraocular pressure (IOP), and tear film break up time (BUT) were measured, and fluorescein and lissamine green staining were performed to uncover possible correlations among the aforementioned parameters. Our results showed that the expression of AQP1 in tears collected by both methods and expressed as multiple bands (measured by densitometry) was higher for the tears collected by OS than for those collected by STS. This work forms the basis of future studies aiming to understand and establish the involvement of AQPs in the production and secretion of tears.Aquaporins (AQPs) are a family of thirteen membrane proteins that play an essential role in the transport of fluids across the cell plasma membrane. Recently, the expression of AQPs in different ocular tissues and their involvement in the pathophysiology of eye diseases, have garnered attention. Considering that literature on AQP expression in the lacrimal glands and their secretion is scarce, we aimed to characterise AQP1 expression in the tears of healthy dogs using two tear collection methods (Schirmer tear strips (STS) and ophthalmic sponges (OS)). Fifteen healthy dogs, free of ophthalmic diseases, were included in the study. Tear collection was performed by using STS in one eye and OS in the other. After the extraction of proteins from the tears, the expression of AQP1 was analysed by Western blotting. AQP1 was expressed as a band of 28 kDa. In addition, differences were observed in the expression of AQP1 and in the correlation between tear volume and protein concentration, in tears collected by the two different methods. Our results suggest that AQP1 has a specific role in tear secretion; further research is required to assess its particular role in the function of the ocular surface in eye physiology and pathology.

A novel and less invasive technique to assess cytokine profile of vitreous in patients of diabetic macular oedema.

PurposeA pilot study to validate the collection of vitreous reflux (VR) after intravitreal injection using Schirmers tear strips was carried out. We assessed its efficiency for proteomics studies by estimating the differential expression of 27 cytokines using multiplexed bead array in diabetic macular oedema and proliferative diabetic retinopathy. To set, validate and assess the efficacy of Schirmer tear strips for collecting VR in patients undergoing intravitreal injections for diabetic macular oedema (DME).Patients and methodsVR samples were collected from 11 eyes of DME patients after intravitreal injections using Schirmer tear strips. Undiluted vitrectomy samples were obtained from six eyes of non-diabetic patients with idiopathic macular hole and seven eyes of diabetic patients with high-risk proliferative diabetic retinopathy (Hr-PDR), which were also subsampled on the Schirmer tear strips. Tear sampling was done in a subset of the DME patients. Total protein concentration between VR and vitrectomy samples was compared. Levels of the set of 27 cytokines in Schirmer tear strips samples were measured. Inter-group comparison for cytokines was done using Mann-Whitney U-test.ResultsSimilar protein concentration in VR samples and vitrectomy samples (P<0.05) was obtained. Tear protein contamination was not detected in VR samples. In comparison with no-DR patients, 25 and 20 of the measured 27 cytokines were significantly elevated (P<0.05) in the Hr-PDR and DME patients, respectively. As compared with no-DR patients, vascular endothelial growth factor was only moderately elevated in DME patients (P>0.05), but significantly elevated in Hr-PDR patients (P<0.05). Interleukin 1 receptor antagonist/interleukin 1b (IL1RA/IL1b) ratio was 13 times higher in DME patients as compared with Hr-PDR group.ConclusionWe demonstrated a simple, safe method of VR sampling. This technique provides a pure, albeit small, vitreous sample for proteomics. IL1RA/IL1b ratio was found to be 13-fold higher in the DME group as compared to the Hr-PDR.

The formation mechanism of tear strips on stretched Ti-22Al-25Nb alloy sheets

This paper reports the presence of tear strips on the surface of a Ti-22Al-25Nb alloy sheet stretched at 960 °C. The test piece reveals a “bamboo”-shaped pattern on its surface, which severely affects the quality of the alloy. Microstructure analysis indicates that the formation mechanism of the tear strip is related to both the rich α2 phase layer and the interfacial B2 phase dynamic recrystallization layer between the α2 phase layer and the substrate metal.

Benchmark the best factory data collection system (FDC) using AHP-GRA method

Purpose – The purpose of this paper is to propose a multi-criteria decision making method to evaluate factory data collection (FDC) system alternatives. Design/methodology/approach – “Information” in is fundamental resource to the success of any business which is as valuable as capital or people. The factory data (information) collection system (FDC system) consists of the various paper documents, terminals, and automated devices located throughout the plant for collecting data on shop floor operations for compiling and processing the data. In this paper, nine alternatives of FDC methods are evaluated on the basis of eight criteria. The weight of each criterion is determined using Analytic Hierarchy Process, and the same weights are used to evaluate alternatives of FDC system using Grey Relational Analysis – A multi-criterion decision making method. Findings – The methodology facilitates the selection of the best FDC system that will minimize the data entry time and chances of errors. The methodology suggests Radio-Frequency Identification (RFID) system is the most preferred choice (ideal) among the nine alternatives whereas Operation tear strips is the worst solution. Originality/value – The proposed methodology will provide a useful tool to the decision maker, which may help to eliminate the associated risks during data entry. The selected best FDC system, i.e. RFID is most suitable tool for ERP system to integrate internal (manufacturing) and external (sales and service) management information system.

Dual quantification of dapivirine and maraviroc in cervicovaginal secretions from ophthalmic tear strips and polyester-based swabs via liquid chromatographic–tandem mass spectrometric (LC–MS/MS) analysis

BackgroundTopical microbicidal agents are being actively pursued as a modality to prevent HIV viral transmission during sexual intercourse. Quantification of antiretroviral agents in specimen sources where antiviral activity is elicited is critical, and drug measurements in cervicovaginal fluid can provide key information on local drug concentrations. Two antiretroviral drugs, dapivirine and maraviroc, have gained interest as vaginal microbicidal agents, and rugged methods are required for their quantification in cervicovaginal secretions. MethodsCervicovaginal fluid spiked with dapivirine and maraviroc were applied to ophthalmic tear strips or polyester-based swabs to mimic collection procedures used in clinical studies. Following sample extraction and the addition of isotopically labeled internal standards, samples were subjected to liquid chromatographic–tandem mass spectrometric (LC–MS/MS) analysis using a Waters BEH C8, 50mm×2.1mm, 1.7μm particle size column, on an API 4000 mass analyzer operated in selective reaction monitoring mode. The method was validated according to FDA Bioanalytical Method Validation guidelines. ResultsDue to the disparate saturation capacity of the tested collection devices, the analytical measuring ranges for dapivirine and maravirocin cervicovaginal fluid on the ophthalmic tear strip were 0.05–25ng/tear strip, and 0.025–25ng/tear strip, respectively. As for the polyester-based swab, the analytical measuring ranges were 0.25–125ng/swab for dapivirine and 0.125–125ng/swab for maraviroc. Dilutional studies were performed for both analytes to extended ranges of 25,000ng/tear strip and 11,250ng/swab. Standard curves were generated via weighted (1/x2) linear or quadratic regression of calibrators. Precision, accuracy, stability and matrix effects studies were all performed and deemed acceptable according to the recommendations of the FDA Bioanalytical Method Validation guidelines. ConclusionsA rugged LC–MS/MS method for the dual quantification of dapivirine and maraviroc in cervicovaginal fluid using two unique collection devices has been developed and validated. The described method meets the criteria to support large research trials.

Effect of Autoclave Sterilisation on the Dimensional Stability and Tear Strength of Three Silicone Impression Materials

Objectives: There is a risk of spreading infectious material via non-sterile impressions. The aim of this study was to compare the effect of autoclave sterilisation on dimensional stability and tear strength of impression materials. Methods: Twenty-four specimens were produced using a standard ruled test block for each of three impression materials (Affinis, Aquasil and Speedex) to test dimensional stability. Thirty tear strips for each material were prepared for the tear test (ISO 34-1). Specimens were randomly allocated to 3 different groups (autoclaved, disinfected or untreated). A non-contact scanner was used to analyse dimensional change and a universal testing machine was used to determine tear strengths. Results: There were no significant differences in the test dimensions measured for any of the three impression materials following autoclave treatment compared to the disinfected or untreated control groups. The tear strengths were not adversely affected by autoclave sterilisation at 134°C. Conclusion: These addition and condensation-cured silicone impression materials can be steam autoclaved without adverse effects on dimensional accuracy or tear strength.

Determination of ofloxacin in tear by HPLC–ESI-MS/MS method: Comparison of ophthalmic drug release between a new mucoadhesive chitosan films and a conventional eye drop formulation in rabbit model

Ofloxacin, second-generation fluoroquinolone derivative, is one of the most commonly used to treat and prevent superficial ocular infection in animals and human beings. However, poor bioavailability, rapid elimination, and non compliance by patients are several problems associated with ocular route. Ophthalmic controlled drug delivery offers the potential to enhance the efficacy of treatment for pathological conditions, while reducing the side effects and the toxicity associated with frequent applications. Specific analytical methods to determine drugs in eye are needed to analyze and compare the new controlled release ocular devices with those conventional eye drops. The topical eye administration of ophthalmic drugs induces lachrymation, and the tear promotes a drug wash out. Quantify drugs in tear is a good tool to study their kinetic comportment in the eye. A liquid chromatography-electrospray ionization tandem mass spectrometry (HPLC-ESI-MS/MS) method for quantitation of ofloxacin in rabbits' tears was developed and validated. The tear was collected with tear strips, extracted by a liquid extraction procedure and then separated on an ACE C(18) column with a mobile phase composed of 0.15% aqueous formic acid and methanol (60:40, v/v). Calibration curve was constructed over the range of 10-5000 ng/mL for ofloxacin. The mean R.S.D. values for the intra-run and inter-run precision were 5.15% and 4.35%, respectively. The mean accuracy value was 100.16%. The validated method was successfully applied to determine the ofloxacin concentration in tears of rabbits treated with a mucoadhesive chitosan films and a conventional eye drop formulation.

Hyaluronic acid coated poly-ɛ-caprolactone nanospheres deliver high concentrations of cyclosporine A into the cornea

The objective of this study was to determine cyclosporine A (Cy A) levels in ocular tissues and fluids after topical administration of poly-ɛ-caprolactone (PCL)/benzalkonium chloride (BKC) nanospheres and hyaluronic acid (HA) coated PCL/BKC nanospheres onto healthy rabbit corneas. Nanospheres were prepared by nanoprecipitation and purified by gradient-rate centrifugation. Cy A (0.1%) in either castor oil solution (group 1), PCL/BKC nanosphere formulation (group 2) or HA coated PCL/BKC nanosphere formulation (group 3) was instilled onto rabbit corneas. Tear samples were adsorbed onto Schirmer tear strips. Cy A concentrations of fluid (blood, aqueous humor, tear) and specimen extracts (cornea, conjunctiva, iris/ciliary body) were determined by high performance liquid chromatography–mass spectrometry (LC–MS). The mean corneal Cy A concentration obtained at 0.5, 1, 2, 4, 8 and 24 h following instillation of the formulations ranged between 0.12 and 1.2 ng/mg tissue for group 1, 5.9–15.5 ng/mg tissue for group 2 and 11.4–23.0 ng/mg for group 3 (one-way analysis of variance (ANOVA) and pairwise tests (SNK (Student–Newman–Keuls) and Tukey); p < 0.05). Conjunctival Cy A levels of group 2 and 3 were not significantly different at any of the time points tested. However, there was a significant difference between Cy A concentration of castor oil formulation and that of PCL/BKC nanosphere formulation at 1 and 8 h ( p < 0.05). The mean iris/ciliary body concentrations obtained with the three formulations were not significantly different at any time point with the exception of group 2 levels being higher than those of groups 1 and 3 at 1 h ( p < 0.05). The lowest ocular tear Cy A concentrations (16–114 ng/ml) were found following the instillation of HA coated PCL/BKC nanoparticles (group 3) during the time period tested. Cy A loaded PCL/BKC and HA coated PCL/BKC nanospheres are able to achieve high levels of Cy A in the cornea that is 10–15-fold higher than that is achieved with Cy A solution in castor oil. Nanosphere formulation and HA may play an important role in delivering high levels of cyclosporine A into the cornea.