نتایج جستجو برای: herbal melanin

تعداد نتایج: 29520  

Journal: :Eukaryotic cell 2005
Read Pukkila-Worley Quincy D Gerrald Peter R Kraus Marie-Josée Boily Matthew J Davis Steven S Giles Gary M Cox Joseph Heitman J Andrew Alspaugh

Cryptococcus neoformans is an opportunistic human fungal pathogen that elaborates several virulence attributes, including a polysaccharide capsule and melanin pigments. A conserved Galpha protein/cyclic AMP (cAMP) pathway controls melanin and capsule production. To identify targets of this pathway, we used an expression profiling approach to define genes that are transcriptionally regulated by ...

2012
Doekele G. Stavenga Hein L. Leertouwer Takahiko Hariyama Hans A. De Raedt Bodo D. Wilts

Mature male Calopteryx japonica damselflies have dark-blue wings, due to darkly coloured wing membranes and blue reflecting veins. The membranes contain a high melanin concentration and the veins have a multilayer of melanin and chitin. Female and immature C. japonica damselflies have brown wings. We have determined the refractive index of melanin by comparing the differently pigmented wing mem...

2010
Kyoung-Chan Park Sun Young Huh Hye Ryung Choi Dong-Seok Kim

Increased production and accumulation of melanin are characteristics of a large number of skin diseases, including melasma, post-inflammatory hyperpigmentation and lentigo. A number of clinical agents can reduce normal or abnormal pigmentation, but none of these have achieved satisfactory effects. This review discusses the mechanisms behind the different approaches. Tyrosinase is a pivotal enzy...

2012
Kshitija R. Deshmukh

Melanin producing organism was isolated from a soil sample of Ahmednagar district, Maharashtra using Tyrosine casein media. The isolated organism’s morphology and spore arrangement was studied. The isolated organism was suspected to belong to the genus Streptomyces. Parameter optimization of the Tyrosine casein media with respect to carbon and nitrogen source was done. Starch and L-glycine were...

Journal: :Acta biochimica Polonica 2013
Dominika Michalczyk-Wetula Aleksander Salwiński Małgorzata Popik Monika Jakubowska Przemysław M Płonka

Cancer chemotherapy is associated with serious side effects, including temporary hair loss and impairment of pigmentation. We suspect that ectopic melanin deposition occurring due to chemotherapy may add to these effects worsening the already unpleasant symptoms. We associated the ectopic occurrence of follicular melanin after chemotherapy with splenic melanosis - an interesting example of extr...

Journal: :Otolaryngology--head and neck surgery : official journal of American Academy of Otolaryngology-Head and Neck Surgery 2016
Isaac D Erbele Frank R Lin Yuri Agrawal Howard W Francis John P Carey Wade W Chien

OBJECTIVES Melanin pigmentation is present in the human inner ear. In this study, we quantify the melanin pigmentation in the vestibular system and examine racial differences of vestibular melanin pigmentation using human cadaveric temporal bone specimens. STUDY DESIGN Basic research. SETTING Laboratory. SUBJECTS AND METHODS Light microscopy was used to examine specimens from 40 left temp...

2002
J. It. WHITT

[Z-W]Thiouracil and [%]thiouracil are incorporated into the melanin of chick retinal pigment epithelium incubated in vitro. This synthesis of a thiouracil pheomelanin (thiolcuntaining melanin) can be used to measure the rate of melanin synthesis in living cells. Thiouracil incorporation is dependent on tyrosinase activity: incorporation is inhibited by phenylthiourea, a tyrosinase inhibitor, an...

Journal: :Microbiology 2009
Helene C Eisenman Susana Frases André M Nicola Marcio L Rodrigues Arturo Casadevall

Recently, several pathogenic fungi were shown to produce extracellular vesicles that contain various components associated with virulence. In the human pathogenic fungus Cryptococcus neoformans, these components included laccase, an enzyme that catalyses melanin synthesis. Spherical melanin granules have been observed in the cell wall of C. neoformans. Given that melanin granules have dimension...

Journal: :Biochemistry 2008
Junyan Zhong Susana Frases Hsin Wang Arturo Casadevall Ruth E Stark

Melanins serve a variety of protective functions in plants and animals, but in fungi such as Cryptococcus neoformans they are also associated with virulence. A recently developed solid-state nuclear magnetic resonance (NMR) strategy, based on the incorporation of site-specific (13)C-enriched precursors into melanin, followed by spectroscopy of both powdered and solvent-swelled melanin ghosts, w...

Journal: :The Journal of antibiotics 1995
R Hashimoto S Takahashi K Hamano A Nakagawa

Melanin biosynthesis in insects involves the following three key steps: oxidation of tyrosine to dopa by monophenoloxidase (tyrosinase), conversion of dopa to dopachrome by diphenoloxidase and formation of melanin by polymerization of dopachrome.1] Whenthe larval haemolymphof Bombyxmori is exposed to air, it changes from pale yellow to black. This color change is based on melanin formation, by ...

نمودار تعداد نتایج جستجو در هر سال

با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید