Evolution of ZnS Nanoparticles via Facile CTAB Aqueous Micellar Solution Route: A Study on Controlling Parameters

Synthesis of semiconductor nanoparticles with new photophysical properties is an area of special interest. Here, we report synthesis of ZnS nanoparticles in aqueous micellar solution of Cetyltrimethylammonium bromide (CTAB). The size of ZnS nanodispersions in aqueous micellar solution has been calculated using UV-vis spectroscopy, XRD, SAXS, and TEM measurements. The nanoparticles are found to be polydispersed in the size range 6–15 nm. Surface passivation by surfactant molecules has been studied using FTIR and fluorescence spectroscopy. The nanoparticles have been better stabilized using CTAB concentration above 1 mM. Furthermore, room temperature absorption and fluorescence emission of powdered ZnS nanoparticles after redispersion in water have also been investigated and compared with that in aqueous micellar solution. Time-dependent absorption behavior reveals that the formation of ZnS nanoparticles depends on CTAB concentration and was complete within 25 min

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Not AvailableIn the present study, ontogenetic expression of different innate immune genes in the Toll pathway of tiger shrimp, Penaeus monodon, such as TLR, myeloid differentiation factor 88 (MyD88) and tumor necrosis factor (TNF) receptor-associated factor 6 (TRAF6), was investigated in different developmental stages. Ontogenetic expression by real-time PCR revealed constitutive expression of these genes in all the developmental stages selected. TLR expression was found to be the highest in PL4, whereas MyD88 and TRAF6 showed the highest expression in eggs. The ubiquitous expression of TLR, MyD88 and TRAF6 in different developmental stages of P. monodon indicates the role of these genes in protecting the animals during early development. Immersion challenge of PL 18 with V. harveyi resulted in significant upregulation of TRAF6 at all time-points and significant upregulation of TLR at most of the time-points selected; however, MyD88 showed differential modulation pat- tern. In contrast to the bacterial challenge, WSSV infection in PL18 did not show any significant change in the expression of TRAF6, except for a downregulation observed at 12 to 48 hpi. However, TLR and MyD88 showed moderate increase in their expression, especially at late time-points. The responses of these genes to V. harveyi and WSSV immersion challenges in the juveniles (average body weight 3 g) of P. monodon were investigated in selected tissues including gill, hepatopancreas, and different parts of gastrointestinal tract such as foregut (stomach), midgut and hindgut. Temporal expression analysis revealed complete downregulation of PmMyD88 at most of the time-points in the gill following V. harveyi challenge and significant induction of PmTRAF6 at all time-points following WSSV infection. Immersion challenge with V. harveyi resulted in enhanced expression of TRAF6 in stomach and MyD88 in hepatopancreas showed similar pattern of expression post-WSSV challenge. Other tissues showed varying levels of induction of these genes at different time-points following pathogen challenge. The results of the present study suggest that both bacterial and viral challenges through immersion modulates the genes involved in the Toll pathway, and this might play an important role in the immune defense of post-larvae and juveniles of P. monodon.Not Availabl

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Not AvailableTilapiines are one of the most widely farmed fish species and currently being cultured in > 100 countries in the World. Over the last few years, large-scale mortalities have been reported in tilapia due to infection with orthomyxo-like virus i.e. Tilapia Lake Virus (TiLV) which is considered as a threat to global tilapia industry. In the present study, we report outbreaks of TiLV disease in farmed tilapia in two states, West Bengal and Kerala from India. Diseased fish exhibited lethargy, inappetance and skin erosions with > 85% mortality. TiLV infection was confirmed on the basis of PCR amplification and sequencing of segment 3 of TiLV, histopathology, infection of fish cell line and bioassay. CLUSTALW alignment of the partial sequences of segment 3 of the TiLV revealed that North 24 Parganas (MF502419) and South 24 Parganas (MF582636) of West Bengal, India showed 97.2% and Ernakulam, Kerala, India (MF574205) showed 96.4% similarity with TiLV from Israel (KJ605629.1). In histopathology, typical syncytial giant cells in liver and congestion of the blood vessels along with haemorrhages in sections of brain tissue were observed. The filtered tissue homogenate prepared from liver and brain of affected tilapia produced cytopathic effects in CFF cell line derived from Pristolepis fasciatus. The disease was successfully reproduced in naive tilapia following injection of culture supernatant from infected cell line and TiLV was successfully reisolated from experimentally infected tilapia. This is the first report of TiLV from India and adds to the reports of TiLV outbreaks in five countries across three continents.Not Availabl

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Not AvailableTilapiines are one of the most widely farmed fish species and currently being cultured in > 100 countries in the World. Over the last few years, large-scale mortalities have been reported in tilapia due to infection with orthomyxo-like virus i.e. Tilapia Lake Virus (TiLV) which is considered as a threat to global tilapia industry. In the present study, we report outbreaks of TiLV disease in farmed tilapia in two states, West Bengal and Kerala from India. Diseased fish exhibited lethargy, inappetance and skin erosions with > 85% mortality. TiLV infection was confirmed on the basis of PCR amplification and sequencing of segment 3 of TiLV, histopathology, infection of fish cell line and bioassay. CLUSTALW alignment of the partial sequences of segment 3 of the TiLV revealed that North 24 Parganas (MF502419) and South 24 Parganas (MF582636) of West Bengal, India showed 97.2% and Ernakulam, Kerala, India (MF574205) showed 96.4% similarity with TiLV from Israel (KJ605629.1). In histopathology, typical syncytial giant cells in liver and congestion of the blood vessels along with haemorrhages in sections of brain tissue were observed. The filtered tissue homogenate prepared from liver and brain of affected tilapia produced cytopathic effects in CFF cell line derived from Pristolepis fasciatus. The disease was successfully reproduced in naive tilapia following injection of culture supernatant from infected cell line and TiLV was successfully reisolated from experimentally infected tilapia. This is the first report of TiLV from India and adds to the reports of TiLV outbreaks in five countries across three continents.Not Availabl