Vertical transmission and prevalence of white spot syndrome virus (WSSV) in the wild spawning population of the Indian white shrimp, Penaeus indicus

White spot disease, caused by white spot syndrome virus (WSSV), has historically been the most devastating disease in shrimp aquaculture industry across the world. The mode of virus transmission is the most crucial stage in the dynamics and management of virus infection. This study explored the mechanism of vertical transmission of WSSV in Indian white shrimp, Penaeus indicus, potential native species for domestication and genetic improvement, using quantitative real time PCR (q RT PCR), light and electron microscopy, and in situ hybridization. Wild brooders of P. indicus (n = 2576) were sampled along the South east coast of India, during 2016 to 2021. Of these ∼ 58 % of the brooders were positive for WSSV, and almost 50 % of infected wild brooders were at the various stages of reproductive maturation. WSSV-PCR positive brooders (n = 200) were analysed for vertical WSSV transmission. The q RT PCR studies of reproductive tissues revealed that 61 % (n = 13) of spermatophore, 54 % (n = 28) of immature ovaries and 48 % (n = 27) of ripe ovaries were infected with WSSV. The lowest level of infection was recorded in females with ripe ovaries (6.84 × 101 ± 9.79 × 100 ng genomic DNA) followed by fertilized eggs (1.59 × 102 ± 3.69 × 101 ng genomic DNA), and larvae (nauplius and zoea). The histology of gravid females with high WSSV copies showed pyknotic and karyorrhectic germinal vesicle with degenerated cortical rods. Conversely, the gravid females with low WSSV copies showed fully developed ovary without characteristic signs of WSSV infection. Transmission electron microscopic studies clearly established the presence of WSSV particles in both ovaries and spermatophores. When subjected to in situ hybridization, WSSV-specific signals were observed in connective tissues of spermatophore, although gravid ovary and fertilized eggs were failed to produce WSSV specific signals. The present study provides the first molecular and histological evidence for trans-ovarian vertical transmission of WSSV. Development of disease-free base population being the cornerstone and first step in establishing the breeding program, the present findings could be a basis for development of such programs.

COVID-19 and Stroke Trends in A Tertiary Care Center from South India -Our Monsoon Experience

INTRODUCTION

The unprecedented challenges during the COVID pandemic and the subsequent lockdown had resulted in a delay in treatment metrics for acute stroke. There is a rising concern that COVID-19 co-infection can adversely affect stroke outcome. We aim to investigate the impact of COVID-19 in the management of stroke patients. We also compared the differences in stroke manifestations, etiological pattern, treatment course, and outcome of acute stroke patients in COVID-19 confirmed cases.

METHODOLOGY

A single-center retrospective study was done at the Stroke Unit, Government Medical College, Thiruvananthapuram. Consecutive patients of acute stroke confirmed by imaging, presenting within 24 hours of the onset of symptoms in May to July 2020 and May to July 2019, were included. The primary data variables included baseline demographics, risk factors, admission NIHSS, stroke timings, thrombolysis rate, TOAST etiology, mRS at discharge, and in-hospital mortality.

RESULTS

Strokes with higher NIHSS, arrival blood sugar and blood pressure, and delays in door-to-CT and door-to-needle time were more during the pandemic. Intravenous thrombolysis was less and mortality was higher in COVID-19 strokes during the pandemic. COVID-19-positive stroke patients had more hemorrhagic strokes, more severe strokes with low CT ASPECTS, more hemorrhagic transformation, high in-hospital mortality, and poor functional outcome at discharge and 3 months.

CONCLUSION

Our study was a hypothesis-generating study with a limited number of patients. This study has reconfirmed the higher severity of the stroke, with a higher mRS score and mortality during the pandemic, especially among COVID-19-positive stroke patients.

Microbial community composition associated with early developmental stages of the Indian white shrimp, Penaeus indicus

Gut microbiota is known to influence the physiology, health, nutrient absorption, reproduction, and other metabolic activities of aquatic organisms. Microbial composition can influence intestinal immunity and are considered as health indicators. Information on gut microbial composition provides potential application possibilities to improve shrimp health and production. In the absence of such information for Penaeus indicus, the present study reports the microbial community structure associated with its early developmental stages. Bacterial community associated with the early developmental stages (egg, nauplii, zoea, mysis, PL1, PL6 and PL12) from two hatchery cycles were analysed employing 16S rRNA high throughput sequencing. Proteobacteria and Bacteroidetes, were the two dominant phyla in P. indicus development stages. Sequential sampling revealed the constant change in the bacterial composition at genus level. Alteromonas was dominant in egg and nauplii stage, whilst Ascidiaceihabitans (formerly Roseobacter) was the dominant genera in both PL6 and PL12. The bacterial composition was highly dynamic in early stages and our study suggests that the mysis stage is the critical phase in transforming the microbial composition and it gets stabilised by early post larval stages. This is the first report on the composition of microbiota in early developmental stages of P. indicus. Based on these results the formation of microbial composition seems to be influenced by feeding at early stages. The study provides valuable information to device intervention strategies for healthy seed production.

Amelioration of oxidative stress by Tabernamontana divaricata on alloxan-induced diabetic rats

Objective:

The purpose of this study was to evaluate the anti-diabetic activity of ethanol extract of Tabernamontana divaricata (L.) and its ameliorative effect on oxidative stress in alloxan-induced diabetic rats.

Materials and Methods:

Diabetes was induced by single intraperitoneal injection of alloxan monohydrate (140 mg/kg body weight). Methanol extract of T. divaricata was administered at the doses of 100 and 200 mg/kg body weight in diabetic induced rats including glibenclamide (3 mg/kg) as a reference drug. In the continuous 21 days treatment, fasting blood glucose level was determined on 0, 7, 14 and 21 days. On day 21, serum lipid profiles and glycosylated hemoglobin, liver antioxidant enzymes levels were estimated.

Results:

Experimental findings showed a significant anti-diabetic potential of the extract in terms of reduction in blood glucose levels and a correct effect on the altered biochemical parameters. Observed data were found statistically significant in correction of antioxidant enzyme level accompanied with diabetes, particularly at the dose of 200 mg/kg body weight.

Conclusion:

Based on the results, it can be concluded that the T. divaricata is found to be effective in type 2 diabetes in rats and to have an ameliorative effect on the associated oxidative stress.

Malignant thyroglossal duct cyst with synchronous occult thyroid gland papillary carcinoma

A 52-year-old male was referred to our department with complaints of a painless midline neck swelling. Clinico-radiological evaluation suggested a 6 × 5 cm thyroglossal cyst with non-palpable nodules in isthmus and right lobe of thyroid gland. FNAC of the thyroglossal cyst was suggestive of papillary carcinoma. He underwent Sistrunk's operation, total thyroidectomy, and central compartment neck dissection. Co-existence of papillary carcinoma of thyroid gland and thyroglossal cyst is a rare presentation and in this report, we describe our management and propose an evidence-based algorithm to assist decision-making in the management of these patients in future.

Algoriphagus shivajiensis sp. nov., isolated from Cochin back water, India

Novel orange-pigmented, Gram-negative, rod-shaped, non-motile bacteria, designated strains NIO-S3(T) and NIO-S4, were isolated from a water sample collected from Cochin back waters, Thanneermukkom and Arookutty, Kerala, India. Both strains were positive for oxidase and catalase activities, and hydrolyzed gelatin and Tween 40. The predominant fatty acids were iso-C15:0, anteiso-C15:0, iso-C17:0 3OH, C16:1ω7c/C16:1ω6c (summed feature 3) and iso-C17:1ω9c/C16:0 10-methyl (summed feature 9), whereas MK-7 was the major respiratory quinone, and phosphatidylethanolamine, two unidentified phospholipids and one unidentified lipid were the only polar lipids. The DNA G+C content of the two strains was 43.7 and 43.6mol%, respectively. The 16S rRNA gene sequence analysis indicated that they were members of the genus Algoriphagus and closely related to Algoriphagus olei CC-Hsuan-617(T), Algoriphagus aquatilis A8-7(T), Algoriphagus aquaeductus LMG 24398(T) and Algoriphagus mannitolivorans DSM 15301(T), with pairwise sequence similarities of 96.8, 96.6, 96.2 and 96.2%, respectively. DNA-DNA hybridization between strains NIO-S3(T) and NIO-S4 showed a relatedness of 89%. Based on data from the current polyphasic study, the strains are proposed as a novel species of the genus Algoriphagus, for which the name Algoriphagus shivajiensis sp. nov. is proposed. The type strain of A. shivajiensis is NIO-S3(T) (=JCM 17885(T)=MTCC 11066(T)).

Friend or foe: genetic and functional characterization of plant endophytic Pseudomonas aeruginosa

Endophytic Pseudomonas aeruginosa strain BP35 was originally isolated from black pepper grown in the rain forest in Kerala, India. Strain PaBP35 was shown to provide significant protection to black pepper against infections by Phytophthora capsici and Radopholus similis. For registration and implementation in disease management programmes, several traits of PaBP35 were investigated including its endophytic behaviour, biocontrol activity, phylogeny and toxicity to mammals. The results showed that PaBP35 efficiently colonized black pepper shoots and displayed a typical spatiotemporal pattern in its endophytic movement with concomitant suppression of Phytophthora rot. Confocal laser scanning microscopy revealed high populations of PaBP35::gfp2 inside tomato plantlets, supporting its endophytic behaviour in other plant species. Polyphasic approaches to genotype PaBP35, including BOX-PCR, recN sequence analysis, multilocus sequence typing and comparative genome hybridization analysis, revealed its uniqueness among P. aeruginosa strains representing clinical habitats. However, like other P. aeruginosa strains, PaBP35 exhibited resistance to antibiotics, grew at 25-41°C and produced rhamnolipids and phenazines. PaBP35 displayed strong type II secretion effectors-mediated cytotoxicity on mammalian A549 cells. Coupled with pathogenicity in a murine airway infection model, we conclude that this plant endophytic strain is as virulent as clinical P. aeruginosa strains. Safety issues related to the selection of plant endophytic bacteria for crop protection are discussed.

Recursive framework for joint inpainting and de-noising of photographic films

We address the problem of inpainting noisy photographs. We present a recursive image recovery scheme based on the unscented Kalman filter (UKF) to simultaneously inpaint identified damaged portions in an image and suppress film-grain noise. Inpainting of the missing observations is guided by a mask-dependent reconstruction of the image edges. Prediction within the UKF is based on a discontinuity-adaptive Markov random field prior that attempts to preserve edges while achieving noise reduction in uniform regions. We demonstrate the capability of the proposed method with many examples.

A recursive filter for despeckling SAR images

This correspondence proposes a recursive algorithm for noise reduction in synthetic aperture radar imagery. Excellent despeckling in conjunction with feature preservation is achieved by incorporating a discontinuity-adaptive Markov random field prior within the unscented Kalman filter framework through importance sampling. The performance of this method is demonstrated on both synthetic and real examples.