Bioluminescence of green Noctiluca scintillans from the coastal waters of Kochi (southwest coast of India) and in vivo experiments on bioluminescence in response to mechanical stimuli and its diurnal variations

AbstractThe present communication reports on the occurrence of a multi-species diatom bloom in the upwelled waters along the southwest coast of India. During the late summer monsoon season (September 2009) a multi-species diatom bloom with a pale green discoloration of the sea surface was observed in the coastal waters of southwest coast of India. The bloom spread over an area of approximately 15 km2 along the coastal waters off Kannur (Lat. 11°59.471 N, Long. 75°03.446 E). Total diatom cell density of the bloom area was 16 × 104 cells l−1. Proboscia (=Rhizosolenia) alata (Brightwell) Sandstrom constituted 90% of the total phytoplankton population. Other phytoplankton groups that contributed to the bloom population included Chaetoceros spp., Pseudo-nitzschia spp., Rhizosolenia spp., Coscinodiscus sp., Leptocylindrus danicus, Thalassiosira sp., and Bacteriosira sp. Among these Pseudo-nitzschia multiseries, a toxic species with the ability to produce potent neurotoxin domoic acid, was observed with a cell density of 4 × 103 cells l−1. Surface chlorophyll a concentration of the bloom region was 14.1 μg l−1. Nutrient concentrations of the bloom area were 0.01 μmol l−1 for NO2-N, 0.1 μmol l−1 for NO3-N, 0.83 μmol l−1 for PO4-P and 11.44 μmol l−1 for SiO4.

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Bacterial Growth Efficiency in the Tropical Estuarine and Coastal Waters of Goa, Southwest Coast of India

Microbial Ecology ◽

10.1007/s00248-002-3005-9 ◽

2003 ◽

Vol 45 (1) ◽

pp. 88-96 ◽

Cited By ~ 33

Author(s):

A.S. Pradeep Ram ◽

S. Nair ◽

D. Chandramohan

Keyword(s):

Bacterial Growth ◽

Coastal Waters ◽

Growth Efficiency ◽

Bacterial Growth Efficiency ◽

Southwest Coast Of India ◽

Southwest Coast ◽

Tropical Estuarine

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Antinociceptive modulation by the adhesion GPCR CIRL promotes mechanosensory signal discrimination

eLife ◽

10.7554/elife.56738 ◽

2020 ◽

Vol 9 ◽

Author(s):

Sven Dannhäuser ◽

Thomas J Lux ◽

Chun Hu ◽

Mareike Selcho ◽

Jeremy T-C Chen ◽

...

Keyword(s):

High Threshold ◽

Mechanical Stimuli ◽

In Vivo Experiments ◽

Physiological Processes ◽

Signal Discrimination ◽

Low Threshold ◽

Sensory Responses ◽

Opposing Effects ◽

Adhesion Gpcr

Adhesion-type GPCRs (aGPCRs) participate in a vast range of physiological processes. Their frequent association with mechanosensitive functions suggests that processing of mechanical stimuli may be a common feature of this receptor family. Previously, we reported that the Drosophila aGPCR CIRL sensitizes sensory responses to gentle touch and sound by amplifying signal transduction in low-threshold mechanoreceptors (Scholz et al., 2017). Here, we show that Cirl is also expressed in high-threshold mechanical nociceptors where it adjusts nocifensive behaviour under physiological and pathological conditions. Optogenetic in vivo experiments indicate that CIRL lowers cAMP levels in both mechanosensory submodalities. However, contrasting its role in touch-sensitive neurons, CIRL dampens the response of nociceptors to mechanical stimulation. Consistent with this finding, rat nociceptors display decreased Cirl1 expression during allodynia. Thus, cAMP-downregulation by CIRL exerts opposing effects on low-threshold mechanosensors and high-threshold nociceptors. This intriguing bipolar action facilitates the separation of mechanosensory signals carrying different physiological information.

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