Swept-source optical coherence tomography objective composite activity score for uveitis

PURPOSE

To develop an objective intraocular inflammation composite score.

METHODS

Cross-sectional study. Non-invasive image acquisition and processing were conducted from April 2017 to April 2019. Inflammation-grade stratified eyes from patients with active, inactive uveitis and healthy controls were recruited. After clinical assessment, four anterior and posterior segment image acquisition protocols per eye, using swept-source optical coherence tomography (SS-OCT), were performed at inclusion. Eight imaging biomarkers in three domains: anterior, intermediate and posterior were studied. They were ranked and selected by discriminatory power and correlation with clinical scores. A final SS-OCT-derived composite uveitis activity score (SS-UAS) was developed through multiple linear regression.

RESULTS

We studied 224 eyes with uveitis (165 active and 59 inactive) from 165 patients (mean age 46.6 SD 15.5 years; 55.3% women) and 38 eyes from 19 healthy controls (mean age 43.6 SD 17.1; 47% women). The selected SS-OCT-derived biomarkers to build the final score were anterior chamber hyper-reflective dots (anterior), high-definition relative vitreous intensity (intermediate) and the averaged thickened retinal index (posterior). Swept-source (SS)-UAS was highly discriminant between active and inactive, and between active and healthy eyes (means 2.06 SD 1.86, 0.93 SD 0.44, and 0.96 SD 0.38, respectively, both p -, Mann-Whitney U). Construct validity (Cronbach's alpha = 0.7), internal consistency, criterion validity and reliability (concordance correlation coefficient intra-rater = 0.99, 95% CI: 0.98-0.99; inter-rater = 0.98, 95% CI: 0.96-0.99) were favourable.

CONCLUSIONS

Global intraocular inflammation can potentially be staged and scored objectively, continuously, consistently and in a valid manner through the combined processing of SS-OCT scans.

Her2-Positive and Microsatellite Instability Status in Gastric Cancer-Clinicopathological Implications

Gastric cancer (GC) is one of the leading causes of cancer-related death. The combination of new molecular classifications with clinicopathological data could contribute to the individualization of patients and to the development of new therapeutic strategies. We examined the various associations in two molecular types of GC: HER2-positive (human epidermal growth factor receptor 2) and microsatellite instability (MSI), assessing their influence on treatment and prognosis. A retrospective study of 142 GC patients was performed with molecular characterization through HER2 overexpression and DNA repair protein expression for MSI. The percentage of HER2-positive tumors was 13.4%, predominantly in men. Correlations were found with intestinal type, metastases, advanced stages and chemotherapy. Almost 75% of HER2-positive patients died. MSI occurred in 16.2%, associated with advanced age, female sex, distal location and intestinal type. These patients had few metastases and low stages. The percentage of deaths was higher among MSI patients who received perioperative chemotherapy. The determination of HER2 and MSI status in GC is important for their association with specific clinicopathological features and for their prognostic and predictive value.

Antituberculous Treatment Itself Might Prevent Visual Impairment in Presumed Tuberculosis-Related Uveitis

Purpose: To study the risk factors for visual loss in presumed tuberculosis-related uveitis (TRU).Methods: Retrospective observational cohort study of patients with TRU, either treated or not for tuberculosis, from January 2005 to January 2017. Clinical and demographic variables were recorded. Main outcome measure was a loss of visual acuity (VA) of ≥2 Snellen lines. A Generalized Estimation Equation was used to control between-eyes bias. A backward stepwise logistic regression multivariate analysis was conducted to elucidate independent risk factors.Results: One hundred and thirty-eight eyes from 82 patients were included. There were 45 males, median age at onset of uveitis was 40 years (Interquartile range, IQR 24). The median follow-up was 36 months (IQR 49.75) and 51 patients completed antituberculous treatment (ATT) for a mean of 9.37 months. In the multivariate model, ATT was the only independent protective factor for loss of VA (OR 0.13, 95% CI 0.04-0.37, p < 0.001).Conclusion: ATT itself may prevent visual loss in TRU.

Morphological and morphometric changes in rat optic nerve microvessels in a glaucoma experimental model

AIM

To study the morphological and morphometric changes produced in the capillaries of the optic nerve (ON) head and initial portion after the experimental increase in intraocular pressure (IOP).

MATERIAL AND METHODS

Wistar rats underwent cauterization of three episcleral veins, which produced an immediate increase in the IOP, and was maintained for 3 months. Sagittal sections of the eyeball were studied with immunohistochemical techniques, using a primary antibody to GLUT-1. The GLUT-1 positive capillaries were counted, and measurements were made of the area, perimeter and mean diameter.

RESULTS

Microscopic examination of sections of the ON of control rats revealed a lower density and larger caliber of capillaries in the prelaminar region as compared with the other regions of the ON (P<.05). Comparison between the control and the experimental groups showed a reduction in capillary density (except in the prelaminar region) and a smaller size in all the areas of the ON studied, but less evident in the initial portion (P<.05).

CONCLUSIONS

The increase in IOP was associated with significant qualitative and quantitative changes in the capillaries of the laminar and poslaminar regions of the ON head. These changes appear to return towards parameters compatible with normality in the initial portion of the ON, an area where the vascular collapse was less evident. These findings might explain the significant reduction in ocular blood flow seen in patients with primary open-angle glaucoma.

A kinetic study of isoamyl acetate synthesis by immobilized lipase-catalyzed acetylation in n-hexane

The objective of this work was to propose a reaction mechanism and to develop a rate equation for the synthesis of isoamyl acetate by acylation of the corresponding alcohol with acetic anhydride using the lipase Novozym 435 in n-hexane. The reaction between isoamyl alcohol and acetic anhydride occurred at high rate in first place. Then, if excess alcohol was used, produced acetic acid further reacted with remaining alcohol, leading to yields higher than 100% (based on initial acetic anhydride content). This reaction was much slower and took place only when acetic anhydride had been totally consumed. Optimal pH for Novozym 435 was 7.7. Acetic acid strongly inactivated the enzyme but it was partially caused by the pH drop in the biocatalyst aqueous microenvironment. Acetic anhydride also showed an important inhibition effect. On the contrary, isoamyl alcohol and isoamyl acetate had no negative effect on the lipase. The analysis of the initial rate data showed that reaction followed a Ping-Pong Bi-Bi mechanism with inhibition by acetic anhydride. The kinetic constants were obtained by multiple regression analysis of experimental findings. Equation predictions and experimental reaction rate values matched very well at conditions where acetic acid concentration in the medium was low.

Diagnostic and treatment recommendations on perianal Crohn's disease

Treatment of perianal fistulas in Crohn's disease should be defined on an individual basis. A combined medical and surgical approach is the optimal treatment. Adequate management of perianal fistula disease is based on the presence or absence of active proctitis, anatomic location, and fistula type. Furthermore, the presence of perianal abscesses must be ruled out. This evaluation includes digital rectal examination, endoscopy, and examination under anesthesia combined with pelvic magnetic resonance imaging or anorectal endoscopy ultrasonography findings.

Ultrastructural and quantitative age-related changes in capillaries of the dorsal lateral geniculate nucleus

An ultrastructural and quantitative study of age-related changes in the capillaries of the dorsal lateral geniculate nucleus was carried out using male Wistar rats aged 3, 24, and 28 months. The most important structural changes were found in the basal lamina: thickenings either homogeneously distributed or in specific points; spurs towards the astrocyte sheath; and osmiophilic membrane-like inclusions located within the basal lamina. Endothelial cells and pericytes showed an increase in inclusions and dense bodies in the cytoplasm. The quantitative study showed that the most pronounced alteration was the thickening of the basal lamina, which existed at 24 months. Later, at 28 months, thinning of the endothelial cells was observed together with an increase in mitochondria size and the number of pinocytic vesicles. These changes could be an endothelial cell response to compensate for the increasing transport difficulties caused by the thickening of the basal lamina. The progressive age-related changes observed in the structure of the capillaries might have an effect on the regulation of blood and brain tissue exchanges, and thus might contribute to the development of degenerative alterations in surrounding aging neurones.

Henoch-Schönlein purpura as a clinical presentation of small cell lung cancer

Although exceptionally, Henoch-Schönlein purpura (HSP) may appear as a paraneoplastic syndrome. We report a patient presenting with HSP. A chest X-ray showed a pulmonary nodule, while biopsy of a transthoracic needle aspiration revealed small cell lung cancer. To the best of our knowledge, HSP as a clinical presentation of small cell lung cancer has not been previously reported.

Low predictive value of polymerase chain reaction for diagnosis of cytomegalovirus disease in liver transplant recipients

The polymerase chain reaction (PCR) and viral culture techniques were prospectively compared for the detection of cytomegalovirus (CMV) in blood samples from 24 liver transplant recipients. Nine patients had one or more episodes of viremia, seven of which were clinically symptomatic infections. All samples in which CMV was isolated by culture were positive by the PCR. However, the PCR result was also positive for one or more samples from 11 patients who never developed CMV-related symptoms. Although the PCR is a very sensitive technique for CMV detection in blood samples from liver transplant recipients, it is not useful as a marker of symptomatic CMV disease.