Nanoanalysis of plasma volatile organic compounds using novel DNA-decorated carbon nanotube vapor sensors to noninvasively distinguish ovarian and pancreatic cancer from benign and control samples

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Background: All cells release volatile organic compounds (VOCs) which emanate from body fluids. Our previous preliminary proof of concept study demonstrated that VOCs released from tissue and plasma from ovarian cancer patients are distinct from those released from samples of patients with benign tumors and controls. We seek to create a sensitive and specific, high-throughput screening test for cancer based on analysis of VOCs using novel nanosensors, first targeting cancers with limited clinical screening modalities. In this study we use these sensors to distinguish vapor characteristics in plasma samples from patients with ovarian and pancreatic cancer from benign specimens and controls. Methods: VOCs emanating from.5 mL of thawed, previously banked plasma samples from 93 total individuals were analyzed using a 10-channel nanoelectronic olfaction (“e-nose”) system based on single-stranded DNA-decorated single-walled carbon nanotube (DNA-NT) vapor sensors. Analysis was performed on samples from 20 patients with ovarian cancer, 20 with benign ovarian tumors and 20 age-matched women as well as 13 patients with pancreatic cancer, 10 patients with benign pancreatic disease, and 10 age- and sex-matched controls. All ovarian cancer patients and comparators were non-smokers, while 1 pancreatic patient and 1 corresponding control were current smokers. The sample set included cancer patients with both early- and late-stage disease. All cancer specimens were obtained proximal to initial diagnosis and prior to initiation of therapy. With a test time of approximately 20 minutes per sample, the array output for each individual sample creates a vector in a 10-dimensional sensor space. The ability of the nanosensor array to discriminate between malignant, benign, and healthy groups was investigated using linear discriminant analysis (LDA), support vector machine (SVM), k-nearest neighbors (KNN), and random forest classification algorithms. Each algorithm was trained and tested according to leave-one-out and repeated stratified k-fold cross-validation methods. Results: Compared to their corresponding benign and control specimens, the DNA-NT sensor array was able to discriminate the VOCs from ovarian cancer with 95% accuracy and pancreatic cancer with 90% accuracy. Plasma samples from patients with early-stage ovarian and pancreatic cancers were correctly identified by the algorithms. Conclusions: Nano-enabled DNA coated vapor sensors were able to distinguish the VOC pattern between cancer, benign and control samples in both ovarian and pancreatic cancer. We provide strong evidence that ovarian and pancreatic cancer alters the VOC pattern emanating from plasma. Our results provide optimism that a diagnostic approach based on vapor detection of ovarian and pancreatic cancer is achievable.

Netarsudil/Latanoprost Fixed-Dose Combination for Elevated Intraocular Pressure: Three-Month Data from a Randomized Phase 3 Trial

PURPOSE

To compare the ocular hypotensive efficacy and safety of a fixed-dose combination (FDC) of the Rho kinase inhibitor netarsudil and latanoprost vs monotherapy with netarsudil or latanoprost.

DESIGN

Three-month primary endpoint analysis of a randomized, double-masked, phase 3 clinical trial.

METHODS

Adults with open-angle glaucoma or ocular hypertension (unmedicated intraocular pressure [IOP] >20 and <36 mm Hg at 8:00 AM) were randomized to receive once-daily netarsudil/latanoprost FDC, netarsudil 0.02%, or latanoprost 0.005% for up to 12 months. The primary efficacy endpoint was mean IOP at 8:00 AM, 10:00 AM, and 4:00 PM at week 2, week 6, and month 3.

RESULTS

Mean treated IOP ranged from 14.8-16.2 mm Hg for netarsudil/latanoprost FDC, 17.2-19.0 mm Hg for netarsudil, and 16.7-17.8 mm Hg for latanoprost. Netarsudil/latanoprost FDC met the criteria for superiority to each active component at all 9 time points (all P < .0001), lowering IOP by an additional 1.8-3.0 mm Hg vs netarsudil and an additional 1.3-2.5 mm Hg vs latanoprost. At month 3, the proportion of patients achieving mean diurnal IOP ≤15 mm Hg was 43.5% for netarsudil/latanoprost FDC, 22.7% for netarsudil, and 24.7% for latanoprost. No treatment-related serious adverse events were reported; treatment-related systemic adverse events were minimal. The most frequent ocular adverse event was conjunctival hyperemia (netarsudil/latanoprost FDC, 53.4%; netarsudil, 41.0%; latanoprost, 14.0%), which led to treatment discontinuation in 7.1% (netarsudil/latanoprost FDC), 4.9% (netarsudil), and 0% (latanoprost) of patients.

CONCLUSIONS

Once-daily netarsudil/latanoprost FDC demonstrated IOP reductions that were statistically and clinically superior to netarsudil and latanoprost across all 9 time points through month 3, with acceptable ocular safety.

Utility of digital stereo images for optic disc evaluation

PURPOSE

To assess the suitability of digital stereo images for optic disc evaluations in glaucoma.

METHODS

Stereo color optic disc images in both digital and 35-mm slide film formats were acquired contemporaneously from 29 subjects with various cup-to-disc ratios (range, 0.26-0.76; median, 0.475). Using a grading scale designed to assess image quality, the ease of visualizing optic disc features important for glaucoma diagnosis, and the comparative diameters of the optic disc cup, experienced observers separately compared the primary digital stereo images to each subject's 35-mm slides, to scanned images of the same 35-mm slides, and to grayscale conversions of the digital images. Statistical analysis accounted for multiple gradings and comparisons and also assessed image formats under monoscopic viewing.

RESULTS

Overall, the quality of primary digital color images was judged superior to that of 35-mm slides (P < 0.001), including improved stereo (P < 0.001), but the primary digital color images were mostly equivalent to the scanned digitized images of the same slides. Color seemingly added little to grayscale optic disc images, except that peripapillary atrophy was best seen in color (P < 0.0001); both the nerve fiber layer (P < 0.0001) and the paths of blood vessels on the optic disc (P < 0.0001) were best seen in grayscale. The preference for digital over film images was maintained under monoscopic viewing conditions.

CONCLUSIONS

Digital stereo optic disc images are useful for evaluating the optic disc in glaucoma and allow the application of advanced image processing applications. Grayscale images, by providing luminance distinct from color, may be informative for assessing certain features.

Patients' and physicians' perceptions of the travoprost dosing aid: An open-label, multicenter study of adherence with prostaglandin analogue therapy for open-angle glaucoma or ocular hypertension

OBJECTIVE

This study describes patients' and physicians' perceptions of issues related to dosing adherence with topical therapies for lowering intraocular pressure before and after use of the travoprost dosing aid (Travatan Dosing Aid, Alcon Research Ltd., Fort Worth, Texas).

METHODS

The study had an open-label, multicenter, single-treatment-arm design that included sequential patients with open-angle glaucoma (with or without pigment dispersion or pseudoexfoliation component) or ocular hypertension who were taking any prostaglandin analogue monotherapy. Ten participating physicians were chosen on the basis of factors such as their experience, qualifications, and previous clinical study participation. The study consisted of 2 visits: screening and week 4. Patients were asked to complete a survey about their medication adherence before study entry at the screening visit and at study exit during the week-4 visit. In addition, each physician was asked to complete an entry and exit survey on each patient as well as a survey to provide feedback on the travoprost dosing aid.

RESULTS

Of the 87 enrolled patients, 6 did not complete the exit survey; therefore, 81 patients were included in the intent-to-treat analysis. Mean (SD) age at enrollment was 65.4 (11.6) years; 61.7% (50/81) of the patients were women and 60.5% (49/81) were white. Most patients (96.3% [78/81]) had open-angle glaucoma. Participating physicians perceived that problems involving dosing and adherence were reduced after patients used the dosing aid. Physicians indicated that they would recommend continued use of the travoprost dosing aid for 91.3% (73/80) of patients. All 10 participating physicians said that they would recommend the dosing aid to patients in the future. Of the 81 patients, the majority (68.8% [55/80]) indicated that they would like to continue using the travoprost dosing aid. For 67.5% (54/80) of patients, dosing adherence as recorded by the travoprost dosing aid was >70%. The dosing lever (39.7% [31/78]) and the visual alarm (29.5% [23/78]) were the 2 most favored features of the dosing aid reported by all evaluable patients. The majority of patients (58.8% [47/80]) indicated that they were "relieved" or "very relieved" that the doctor was able to monitor when they dosed their medication; few (7.5% [6/80]) were "concerned" or "very concerned" that the doctor was able to monitor their dosing.

CONCLUSIONS

The travoprost dosing aid was perceived to be effective in reminding this group of patients to take their medication as prescribed. In this study, the device was well accepted by both patients and physicians.

Laser Doppler flowmetry in asymmetric glaucoma

PURPOSE

To evaluate the relationship between extent of glaucoma damage and optic nerve blood flow, we investigated optic nerve head bloodflow in patients with asymmetric glaucoma damage between their two eyes and also in glaucomatous eyes with asymmetric damage inferiorly versus superiorly.

METHODS

From our institutional practice, 16 subjects with asymmetric glaucoma damage between their two eyes and 25 eyes of 20 patients with asymmetric damage superiorly versus inferiorly were included in the study. Determinations of relative optic nerve head blood flow, velocity, and volume were obtained with laser Doppler flowmetry in the superotemporal and inferotemporal neuroretinalrim and in the cup. Means of flow (Flow(3)), velocity (Vel(3)), and volume (Vol(3))were calculated from these three measurement sites, and eyes or hemidisks with greater glaucomatous damage were compared to eyes or hemidisks with less damage.

RESULTS

For subjects with asymmetric glaucoma damage between eyes, Flow(3) and Vel(3) were significantly lower in the eyes with worse glaucoma damage(mean difference = 2.09, p = 0.005, and mean difference = 0.05, p = 0.002,respectively). When comparing optic disks displaying within-eye asymmetry, the hemidisk with greater damage showed significantly lower blood velocity than the hemidisk with less damage (mean difference = 0.05, p = 0.013); however,no difference in blood flow or volume was detected.

CONCLUSIONS

This study provides additional evidence that impaired optic nerve circulation is associated with the extent of glaucomatous pathology.

Association between lower optic nerve laser Doppler blood volume measurements and glaucomatous visual field progression

AIM

To perform a preliminary assessment of the relation between optic nerve circulatory parameters and glaucomatous visual field progression.

METHODS

This study included 29 eyes of 23 patients with open angle glaucoma that had typical glaucomatous nerve fibre bundle visual field defects and increased cup to disc ratios. Laser Doppler flowmetry (Oculix) was used to measure relative optic nerve blood volume (Vol), velocity (Vel) and flow in the superior temporal (ST) and inferior temporal (IT) neuroretinal rim of the optic nerve. After blood flow measurements patients were followed for 6-62 months (mean 33 (SD 17) months) and 2-11 Humphrey visual fields (4.7 (2.6) fields) were obtained. Progression of glaucoma was assessed by the slope of the corrected pattern standard deviation (CPSD) values versus time, which was calculated manually for each eye using regression analysis.

RESULTS

A significant negative correlation was observed between Vol in the IT rim and the CPSD slope (r=-0.56, p=0.002); patients with lower Vol tended to show faster progression of glaucomatous field damage than those with higher Vol. When the eyes were arbitrarily divided into two groups according to lower Vol (0.32 (0.06) arbitrary units, AU, n=15) or higher Vol (0.49 (0.06) AU, n=14), those with lower Vol had significantly worse mean CPSD slopes (0.50 (0.48) dB/year) than those with higher Vol (-0.67 (1.38) dB/year; Student's t test, p=0.009).

CONCLUSIONS

In the IT rim, the area most prone to develop glaucomatous field damage, lower Vol is associated with subsequently faster CPSD progression. These measurements suggest that circulatory abnormalities may have a role in the development of glaucoma.

Comparison of phacotrabeculectomy with 5-fluorouracil, mitomycin-C, and without antifibrotic agents

BACKGROUND AND OBJECTIVE

To evaluate the potential benefits, complications, and prognostic risk factors for failure of phacotrabeculectomy performed with or without 5-fluorouracil (5-FU) and mitomycin-C (MMC).

PATIENTS AND METHODS

Retrospective chart review of 78 patients who underwent phacotrabeculectomy during a 2-year period. Patients were divided into 3 groups, those who received 5-FU (N = 28). MMC (N = 29), or no antifibrotic agent (N = 21).

RESULTS

All 3 groups had statistically significant lower intraocular pressures (IOP) on fewer antiglaucomatous medications at 6-month, 12-month, and last follow-up compared to preoperative levels (P < .05). Intraocular pressures were lower in the group that received MMC compared to the 5-FU group, but not in the group that did not receive antimetabolites, at all time intervals measured (P < .05). Black race was a strong predictor of failure of trabeculectomy (P = 009). No differences in final visual acuity or complications were found between groups.

CONCLUSIONS

Phacotrabeculectomy is effective regardless of antimetabolite use. Race is a strong predictor of failure.