Volumetric quantification of choroid and Haller's sublayer using OCT scans: An accurate and unified approach based on stratified smoothing

BACKGROUND AND OBJECTIVE

The choroid, a dense vascular structure in the posterior segment of the eye, maintains the health of the retina by supplying oxygen and nutrients, and assumes clinical significance in screening ocular diseases including age-related macular degeneration (AMD) and central serous chorioretinopathy (CSCR). As a technological assist, algorithmic estimation of choroidal biomarkers has been suggested based on sectional (B-scan) optical coherence tomography (OCT) images. However, most such 2D estimation techniques are compute-intensive, yet enjoy limited accuracy and have only been validated on OCT image datasets of healthy eyes. Not surprisingly, fine-scale analyses, including those involving Haller's sublayer, remain relatively rare and unsophisticated. Against this backdrop, we propose an efficient algorithm to quantify desired biomarkers with improved accuracy based on volume OCT scans. Specifically, we attempted an accurate, computationally light volumetric segmentation method involving stratified smoothing to detect choroid and Haller's sublayer.

METHODS

For detecting the various boundaries of the choroid and the Haller's sublayer, we propose a common volumetric method that performs suitable exponential enhancement and maintains smooth spatial continuity across 2D B-scans. Further, we achieve suitable volumetric smoothing by primarily deploying light-duty linear regression, and sparingly using compute-intensive tensor voting, and hence significantly reduce overall complexity. The proposed methodology is tested on five health and five diseased OCT volumes considering various metrics including volumetric Dice coefficient and corresponding quotient measures to facilitate comparison vis-à-vis intra-observer repeatability.

RESULTS

On five healthy and five diseased OCT volumes, respectively, the proposed method for choroid segmentation recorded volumetric Dice coefficients of 93.53 % and 93.30 %, which closely approximate the respective reference observer repeatability values of 95.60 % and 95.49 %. In terms of related quotient measures, our method achieved more than 50 % improvement over a recently reported method. In detecting Haller's sublayer as well, our algorithm records statistical performance closely matching that of reference manual method.

CONCLUSION

Advancing the state-of-the-art, the proposed volumetric segmentation, tested on both healthy and diseased datasets, demonstrated close match with the manual reference. Our method assumes significance in accurate screening of chorioretinal diseases including AMD, CSCR and pachychoroid. Further, it enables generating accurate training data for developing deep learning models for improved detection of choroid and Haller's sublayer.

Genetic structure and connectivity among Aedes aegypti populations within Madurai city in Southern India

We investigated the genetic variability and differentiation among 12 Ae. aegypti populations collected within the Madurai city in Tamil Nadu state of Southern India. Genotyping of 12 microsatellite markers in 353 individual samples showed moderate levels of genetic diversity among 12 populations. UPGMA tree, hierarchical clustering, Bayesian clustering and Discriminant Analysis on Principal Components roughly divided these populations into two genetic clusters: main city populations and the populations located at the border of the corporation limit. Significant positive correlation between genetic and geographic distance was observed among 12 populations, however, the correlation was non-significant within each genetic cluster. Population assignment and divMigrate graph depicted less migration between two groups. Overall, the findings of this study provided an overview of Ae. aegypti population structure within an urban setting in India that have implications in effective implementation of vector control in the city area.

Adjunctive Effects of A Piscean Collagen-Based Controlled-Release Chlorhexidine Chip in the Treatment of Chronic Periodontitis: A Clinical and Microbiological Study

INTRODUCTION

PerioChip a bovine origin gelatine based CHX chip has shown beneficial effects in the management of Chronic Periodontitis. A new fish collagen based CHX chip similar to PerioChip is currently available; however this product has not been thoroughly researched.

AIM

The aim of the present study was to evaluate the effectiveness of a new Piscean collagen-based controlled-release chlorhexidine chip (CHX chip) as an adjunctive therapy to scaling and root planing (SRP).

SETTINGS AND DESIGN

The study was conducted as a randomised, split-mouth, controlled clinical trial at Krishnadevaraya College of Dental Sciences, Bangalore, India.

MATERIALS AND METHODS

In a split-mouth study involving 20 sites in 10 patients with chronic periodontitis, control sites received scaling and root planing and test sites received scaling and root planing (SRP) and the intrapocket CHX chip placement as an adjunct. Subgingival plaque samples were collected from both control and test sites at baseline, 11 days and 11 weeks and the anaerobic colony count were assessed. Clinical parameters that were recorded at baseline and 11 weeks were gingival index, Plaque index, Probing pocket depth (PPD), and Clinical attachment level (CAL). Plaque index was recorded additionally at 11 days.

RESULTS

In the test group there was a statistically significant reduction in the total anaerobic colony count, gingival index and plaque scores from baseline as compared to control sites at all time intervals. An additional 0.8mm reduction in mean probing pocket depth was noted in the test group. Gain in Clinical attachment level was comparable in both groups.

CONCLUSION

The adjunctive use of the new collagen-based CHX chip yielded significant antimicrobial benefit accompanied by a reduction in probing depth and a clinical attachment level gain as compared to SRP alone. This suggests that it may be a useful treatment option of nonsurgical periodontal treatment of chronic periodontitis.

Influence of fermented tannery solid waste on morphological, biochemical, yield and nutritional responses of tomato plants

The non-tanned proteinaceous tannery solid waste animal fleshing (ANFL), containing high nutritive value, was hydrolyzed using bacteria Selenomonas ruminantium HM000123 through submerged (SmF) and solid-state (SSF) fermentation processes. In addition, the effects of ANFL fermentative hydrolysate on growth, yield and biochemical properties of tomato plants were investigated. The treatments included T1 (SmF-ANFL), T2 (SSF-ANFL), T3 (recommended dose of NPK fertilizers) and a control without any amendment. Hydrolysates of both SmF-ANFL and SSF-ANFL treatments increased the biomass and yield as evidenced by plant height, stem girth, number of leaves and fruit yield when compared with both NPK and control plants. In this 90-day study, significant (p ≤ 0.05) changes were observed in SSF-ANFL treated plants compared to the other treatments. Protein profile analyzed through SDS-PAGE indicates the expression of a high molecular weight protein (205 kDa) and other proteins in the leaves of the SSF-ANFL treated plants. Overall results revealed that SSF-ANFL can be successfully utilized as a fertilizer particularly for cultivating tomato plants.

Hyperferritinemia and markers of inflammation and oxidative stress in the cord blood of HIV-exposed, uninfected (HEU) infants

OBJECTIVES

The purpose of this study was to evaluate markers of iron status and inflammation/oxidative stress in maternal and cord blood (CB) of HIV-infected and HIV-uninfected women as potential mechanisms for poor outcomes among HIV-exposed, uninfected (HEU) infants.

METHODS

Maternal venous blood and CB specimens were obtained from 87 pregnant women (45 HIV-infected and 42 HIV-uninfected) enrolled at Kalafong Hospital, Pretoria, South Africa. Iron status [serum iron, ferritin and transferrin concentrations, transferrin saturation, soluble transferrin receptor (sTfR) concentration and the sTfR/log ferritin (sTfR/F) index], antenatal exposure to inflammation (CB C-reactive protein and interleukin-6 concentrations and haptoglobin switch-on status) and oxidative stress [total radical trapping ability of CB plasma (TRAP) and chronic oxidative stress (soluble receptor of advanced glycation end-products (sRAGE) concentration] were assessed in laboratory studies.

RESULTS

There were no differences between the HIV-infected and HIV-uninfected groups in maternal haematological and iron indices, except that HIV-infected mothers had decreased white blood cell counts (P = 0.048) and increased serum ferritin concentrations (P = 0.032). Ferritin levels were significantly higher in CB than in maternal blood (P < 0.001) in both groups and further elevated in the CB of HEU infants (P = 0.044). There was also an inverse relationship between CB sTfR/F index and sRAGE (r = -0.43; P = 0.003) in the HIV-infected but not in the HIV-uninfected group.

CONCLUSIONS

Our study showed for the first time that ferritin was significantly elevated in CB of HEU infants. The inverse relationship between sTfR/F index and sRAGE in CB suggests that chronic oxidative stress or RAGE axis activation in HIV-infected mothers may play a role in modulating ferritin levels.

Nutrient and enzymatic changes of hydrolysed tannery solid waste treated with epigeic earthworm Eudrilus eugeniae and phytotoxicity assessment on selected commercial crops

Animal fleshing (ANFL) is the predominant proteinaceous solid waste generated during processing of leather and it is confronting disposal problems. The aim of this study was to assess the potential of epigeic earthworm Eudrilus eugeniae to utilize and transform the fermented ANFL in the solid state (SSF) and submerged state (SmF) into a value added product along a low residence period (25 days). A total of six treatment units containing different waste mixture compositions were established. Fifty healthy and non-clitellated earthworms were introduced in three different treatment containers: control, SSF, and SmF (+worm). Another set of treatment mixtures (control, SSF, SmF) was established without earthworms (-worm) to compare the results. The products were characterized for physico-chemical, enzymatic analysis and seedling growth parameters to compare the differences in the process with and without earthworms. The changes observed in the analytical parameters were in the following order: SSF > SmF > control mixtures (p < 0.05). The vermicompost showed a significant reduction in heavy metals, total organic carbon and an increase in total Kjeldhal nitrogen as compared to the product untreated by earthworms. The maximum enzymatic activities were observed after 21 days of vermicomposting. The relative seed germination of vermicompost extracts were in the order of tomato (Lycopersicon esculentum) > green gram (Vigna radiata) > cucumber (Cucumis sativus) > bottle gourd (Lagenaria siceraria (Mol.) Standl.) and showed no phytotoxicity effects. The results indicated that the combination of both ANFL hydrolysis through fermentation and vermicomposting is a good alternative to the management of this kind of waste.

Studies on the distribution of bacterial isolates in rare earth environment

Rare earth soil is precious, but very common across Arabian coast especially in Chavara, (Quilon district, Kerala) south west coast of India. They are widely distributed but usually occur in small amounts and enhance the soil properties. In the present study, 18 different bacterial isolates were identified from three different samples such as soil and biofilm formed on metal surfaces from the rare earth environment of Chavara using 16S rDNA gene sequencing. The accumulation of rare earth elements (REE) by microbes was studied using FT-IR analysis. In the FTIR spectrum of the test system, a peak at 1548 and 1449 cm(-1) indicates the presence of aromatic nuclei (carboxylic acid), while C=C stretch for C-O-C group was noticed at 1237 cm(-1). Thus significant variations in the peak position confirm the presence of carboxyl group and thus it was confirmed that rare earth elements induce the bacteria to produce carboxylic acid and thereby accumulate rare earth elements.

Phytochelatin systhesis and cadmium uptake of Brassica napus

Soil contamination with cadmium (Cd) poses risk to human health. Metal hyperaccumulator plants play an important role in phytoextraction of heavy metals from such contaminated sites. Accumulation of Cd and its influence on the induction of phytochelatins in Brassica napus was investigated. Brassica napus plants were grown in nutrient culture with 1 and 5 microM Cd for 10 days. The biomass negatively correlates with Cd concentration in the nutrient solution and the reduction in dry weight was significantly higher for the root than the shoot. Cadmium accumulation positively correlates with the Cd concentration in the nutrient solution and the Cd accumulation in root is significantly higher than the shoot. High-performance liquid chromatography (HPLC) analysis revealed the induction of PC2, PC3 and PC4 in response to Cd in B. napus and their concentrations vary with the Cd level in the external solution. In 1 microM Cd treated plants; PC2 was the dominant thiol fraction in the root, followed by PC3 and PC4, whereas in the shoot, PC3 is the dominant species followed by PC4 and PC2. In 5 microM Cd treated plants, the concentration of both PC3 and PC4 are higher than that of PC2 in the roots. In the shoot, the concentration of PC3 and PC4 was higher than the PC2 irrespective of the quantity of Cd uptake, implying that the detoxification of Cd involves higher molecular weight thiol complexes in the shoot. Considering the high aboveground biomass and Cd accumulation in the shoot, B. napus can be a potential candidate for the phytoextraction of Cd.

Giant popliteal aneurysm presenting with foot drop

Popliteal aneurysms are the most common peripheral arterial aneurysm and occur most commonly among older men with established cardiovascular disease. Popliteal aneurysms are asymptomatic or otherwise present with intermittent claudication, pressure symptoms in the popliteal fossa, distal embolization, and, rarely, rupture. We present a patient with a remarkably large popliteal aneurysm of 10 cm presenting as a popliteal swelling with foot drop and no signs of limb ischemia. According to our literature search, it is the largest reported popliteal aneurysm, and its corresponding symptoms are unusual. The diagnostic workup and treatment are presented.

Speciation of heavy metals during co-composting of sewage sludge with lime

During composting the humification of organic matter will have a significant effect on the physicochemical form of existence of heavy metals. Therefore the present study was conducted to investigate the effect of co-composting sewage sludge with lime on heavy metal speciation and the changes in DTPA extractable metals. Metal speciation was conducted to evaluate the redistribution of Cu, Mn, Ni, Pb and Zn in sewage sludge composted with lime. Sewage sludge was mixed with sawdust in 2:1 (w/w fresh weight) and then composted with lime at 0%, 0.63%, 1% or 1.63% (dry weight) for 100 days. The lime addition did not cause any changes in the different forms of Cu and Mn, but the composting process caused transformations of residual form of Cu and Mn into oxidizable and reducible form, respectively. For Ni, the reducible form was mainly transformed into residual form and lime addition decreased this transformation. Major transformation of different forms of Pb was not found, however the residual form of Pb increased with lime addition. The predominant residual form of Zn was mainly transformed into oxidizable form and the lime addition reduced this transformation. Addition of lime to sewage sludge during composting resulted in lower DTPA extractable metal contents. Therefore, lime is a suitable material to co-compost with sewage sludge to reduce the availability of heavy metals.

Phytoremediation and rehabilitation of municipal solid waste landfills and dumpsites: A brief review

Environmental problems posed by municipal solid waste (MSW) are well documented. Scientifically designed landfills and/or open dumpsites are used to dispose MSW in many developed and developing countries. Non-availability of land and need to reuse the dumpsite space, especially in urban areas, call for rehabilitation of these facilities. A variety of options have been tried to achieve the goals of rehabilitation. In the last couple of decades, phytoremediation, collectively referring to all plant-based technologies using green plants to remediate and rehabilitate municipal solid waste landfills and dumpsites, has emerged as a potential candidate. Research and development activities relating to different aspects of phytoremediation are keeping the interest of scientists and engineers alive and enriching the literature. Being a subject of multi-disciplinary interest, findings of phytoremediation research has resulted in generation of enormous data and their publication in a variety of journals and books. Collating data from such diverse sources would help understand the dynamics and dimensions of landfill and dumpsite rehabilitation. This review is an attempt in this direction.

The state of the health care workforce

The shortage of health care workers has emerged as one of the field's biggest long-term challenges. The number of nurses, technicians, pharmacists and even housekeeping staff is on the way down, and worker dissatisfaction is on the way up. The health care workforce is slowly vanishing, and those workers who remain are unhappy. In this special fold-out section, Hospitals & Health Networks looks at this complex problem by analyzing how serious it really is and how bad it's going to get, taking a look at workers' frustration, and offering tips and resources to start to fix it.

Spleno-gonadal fusion. A case report

Examination of a two-year-old boy with bilateral inguinal hernia revealed a firm, smooth, non-tender mass continuous with the upper pole of the testis and extending upwards to the inguinal canal. Histological examination revealed splenic tissue. The article describes the details of this case of splenogonadal fusion and quotes 50 further references from literature.

Leiomyoma of the duodenum presenting as a pyogenic liver abscess

Leiomyoma of the duodenum is a rare condition which is most often diagnosed only as an incidental finding at post-mortem. It may present clinically with pain or haemorrhage. A case is described of degeneration of a leiomyoma of the fourth part of the duodenum giving rise to pyogenic liver abscess. There is no previous report of this association in the literature.

Topical thrombin and control of wound haematoma

The frequency of wound haematoma was investigated in 45 prophylactically heparinised patients undergoing abdominal surgery. Thrombin was applied locally to the wound in 15 patients, and in these patients wound haematoma was significantly less common than in the controls.