black pigmentation
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ZooKeys ◽  
2021 ◽  
Vol 1070 ◽  
pp. 151-164
Author(s):  
Geon Hyeok Lee ◽  
Karin Meißner ◽  
Seong Myeong Yoon ◽  
Gi-Sik Min

A new spionid polychaete, Spio pigmentatasp. nov., is described from the southern and western coasts of Korea. This new species differs from its congeners by the combination of the following morphological characteristics: the presence of orange-brown pigmentation on the anterior part of the prostomium, black pigmentation on the peristomium and along the body, U-shaped nuchal organs, a comparatively long extension of metameric dorsal ciliated organs, three pairs of white dots per chaetiger, two to three posterior abranchiate chaetigers, and the presence of tridentate neuropodial hooded hooks. The partial 16S ribosomal DNA (rDNA) and nuclear 18S rDNA sequences of the new species and Spio sp. 2 reported by Abe and Sato-Okoshi (2021) from Japan showed high similarity, indicating that these two specimens belong to the same species. A detailed description and illustrations of the new species, together with molecular information, are provided.


2021 ◽  
pp. 2021059
Author(s):  
Enrique Rodríguez-Lomba ◽  
Belén Lozano-Masdemont ◽  
Lula María Nieto-Benito ◽  
Elisa Hernández de la Torre ◽  
Ricardo Suárez-Fernández ◽  
...  

Introduction: The literature regarding the association of dermoscopic structures with Breslow thickness in melanoma is scarce, limited to small case series, and mostly outdated. Objective: This study determined the dermoscopic patterns, colors and structures that are associatedwith melanoma in situ, thin melanomas (<0.8 mm) and thick melanomas potentially requiring sentinellymph node biopsy according to current guidelines (≥0.8 mm). Methods: A retrospective evaluation of 245 dermoscopic images of primary cutaneous melanomalocated on the trunk or limbs was performed by consensus of 2 dermoscopists. Results: Red-pink, blue-gray and white color, blue-white veil, shiny white streaks, irregular vessels,blue-black pigmentation, milky red areas, pseudolacunae, ulceration and rainbow pattern were associated with thickness ≥0.8 mm, whereas atypical pigmented network, regression and hypopigmentedareas were significantly associated with early melanomas. Limitations: This is a retrospective study performed in a single institution. Melanomas of specialsites were excluded from our evaluation. Dermoscopy is based on subjective evaluations that dependlargely on the observers’ experience. Conclusions: The identification of certain dermoscopic structures and colors might help in the discrimination between thin and thick melanomas.


Author(s):  
Takahiro Shojima ◽  
Yasuyuki Zaima ◽  
Kazuyoshi Takagi ◽  
Tohru Takaseya ◽  
Hiroyuki Otsuka ◽  
...  

We report about a 78-year-old woman with severe aortic valve stenosis (AS). She had heavily calcified and thickened aortic valve leaflets with black pigmentation. After excision of the aortic valve leaflets, biological aortic valve replacement (AVR) was performed. Alkaptonuria was diagnosed and confirmed based on increased urinary excretion of homogentisic acid. She has had no cardiovascular system-related symptoms for 3 years and no evidence of structural valve deterioration. Data on the long-term outcomes of AVR associated with structural valve deterioration that could regulate prosthetic valve selection in alkaptonuria are limited. Therefore, further research on the natural evolution of AS and the rate of structural valve deterioration after AVR is needed to provide an optimal prosthesis for these patients.


2021 ◽  
Author(s):  
Michelle D. Glew ◽  
Dhana G. Gorasia ◽  
Paul J. McMillan ◽  
Catherine A. Butler ◽  
Paul D. Veith ◽  
...  

Porphyromonas gingivalis, a bacterial pathogen contributing to human periodontitis, exports and anchors cargo proteins to its surface enabling the production of black pigmentation using a type IX secretion system (T9SS) and conjugation to A-lipopolysaccharide (A-LPS). To determine whether T9SS components need to be assembled “in situ” for correct secretion and A-LPS modification of cargo proteins, combinations of non-pigmented mutants lacking A-LPS or a T9SS component were mixed to investigate in trans complementation. Re-acquisition of pigmentation only occurred between an A-LPS mutant and a T9SS mutant which coincided with A-LPS modification of cargo-proteins detected by Western blot and co-immunoprecipitation/quantitative mass spectrometry. Complementation also occurred using an A-LPS mutant mixed with outer membrane vesicles (OMVs) or purified A-LPS. Fluorescence experiments demonstrated that OMVs can fuse with and transfer lipid to P. gingivalis leading to the conclusion that complementation of T9SS function occurred through A-LPS transfer between cells. None of the two strain crosses involving only the five T9SS OM component mutants produced black pigmentation implying that the OM proteins cannot be transferred in a manner that restores function and surface pigmentation and hence a more ordered temporal in situ assembly of T9SS components maybe required. Our results show that LPS can be transferred between cells or between cells and OMVs to complement deficiencies in LPS biosynthesis and hemin-related pigmentation to reveal a potentially new mechanism by which the oral microbial community is modulated to produce clinical consequences in the human host. Importance Porphyromonas gingivalis is a keystone pathogen contributing to periodontitis in humans leading to tooth loss. The oral microbiota is essential in this pathogenic process and changes from predominantly Gram-positive (health) to predominantly Gram-negative (disease) species. P. gingivalis uses its type IX secretion system (T9SS) to secrete and conjugate virulence proteins to anionic lipopolysaccharide (A-LPS). This study investigated whether components of this secretion system could be complemented and found that it was possible for A-LPS biosynthetic mutants to be complemented in trans both by strains that had the A-LPS on the cell surface and by exogenous sources of A-LPS. This is the first known example of LPS exchange in a human bacterial pathogen which causes disease through complex microbiota-host interactions.


2021 ◽  
Vol 21 ◽  
pp. 37-41
Author(s):  
I. K. Odubote

Records on 1344 West African dwarf goats collected between 1982 and 1992 were used in this study. The records were used to describe determine the mode of inheritance for certain qualitative traits in the breed. All the goats have the stiff, short and straight hair coat  type. The goat colour was very variable, irregular and this include white, black brown, pied and mixed colours. Nonetheless basic black colour predominate (53.3%). Basic white and brown goats account for 6.8% and 39.9% respectively. All goats studied irrespective of sex were horned. The goats also have a pair of teats observed. Possession of beard is common in all breeding bucks, nonetheless, 11.6% of the females have beard. About two-thirds of thegoats were wattled which could be bilateral (63%) or unilateral (6.2%) but no sex difference was observed. The mean lengths of body hair, ruff on bisket, wattle, beard in males and females were 2.90±0.80cm, 10.90±3,30 cm, 2.40±0.70 cm, 7.40cm±3.20cm and 9.20±2.7cm, respectively. Gene frequencies of 0.66, 0.08, 0.33and 1.0 were obtained for presence of wattle, albinism, black pigmentation and non polled respectively.


2021 ◽  
Author(s):  
Zhaoying Liu ◽  
Haofan Liu ◽  
Yang Xie ◽  
Yingxue Yao ◽  
Xiaofen Xing ◽  
...  

2021 ◽  
Vol 10 (01) ◽  
pp. e39-e41
Author(s):  
Christina Putz ◽  
Franz Josef Putz ◽  
Andreas Keyser ◽  
Christof Schmid

Abstract Background Alkaptonuria is a rare autosomal recessive genetic disorder of tyrosine metabolism, which results in accumulation of homogentisic acid in various tissues, including the cardiovascular system. Case Description We report on a 64-year-old man with mixed aortic valve disease who underwent conventional aortic valve replacement. Intraoperative aortotomy revealed black pigmentation of the intima of the ascending aorta and the aortic valve was observed with thickened and calcified dark black leaflets. Histopathological diagnosis of ochronosis of the aortic valve was made. Conclusion Despite several previous signs and symptoms, the diagnosis of alkaptonuria was not established until aortic valve replacement.


2020 ◽  
Vol 44 (1) ◽  
Author(s):  
Kome Otokunefor ◽  
Blessing O. Famakin ◽  
Dorothy O. Douglas

Abstract Background Fomites have long been known to play a key role in the spread of disease causing agents. Hospital-associated fomites in particular have been linked with transmission of members of the Enterococci sp which are key human pathogens. Few studies have explored the role non-hospital door handles might play as potential sources of these isolates. This study therefore set out to explore this role. Results A total of hundred toilet and office door handles in a tertiary institution in Rivers State, Nigeria, were sampled using the swab and rinse method. The presence and drug susceptibility of Enterococcus was determined using the selective bile esculin agar (BEA) and standard microbiological methods. Growth on BEA was observed in 71% of cases, with more growth (38/50, 76%) observed from toilet door handles. Only 35% of samples produced the characteristic black pigmentation associated with Enterococcus sp. Six different bacterial groups were identified from this subset with Enterococcus sp. making up only 14% (5/35) of the isolates. All (100%) Enterococci were isolated from toilet door handles. Antibiotic susceptibility testing revealed very high levels of resistance (80–100%) against 75% of the test antibiotics. An analysis of the antibiotic resistance pattern of each isolate revealed 11 unique antibiogram patterns. Only 2 of these patterns were associated with the enterococci, with majority (4/5) exhibiting resistance to Augmentin (AUG), Ceftazidime (CAZ), Ceftriaxone (CTR), Cefuroxime (CRX), Cloxacillin (CXC), Erythromycin (ERY), Gentamicin (GEN), Ofloxacin (OFL) (antibiogram of AUG–CAZ–CRX–CTR–CXC–ERY). None of the enterococci, however, was resistant to vancomycin. Conclusion This study reports low level contamination of door handles by enterococci. Identical antibiogram patterns linked with majority of the enterococci could however point at the occurrence of a single clone perhaps indicating single source contamination. Reports of high levels of ampicillin resistance among these isolates are problematic as ampicillin–gentamicin combination is the treatment of choice for nosocomial enterococci pathogens.


Genes ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1399
Author(s):  
Linhai Wang ◽  
Senouwa Segla Koffi Dossou ◽  
Xin Wei ◽  
Yanxin Zhang ◽  
Donghua Li ◽  
...  

Seed coat color is a crucial agronomic trait in sesame (Sesamum indicum L.) since it is strongly linked to seed oil, proteins, and lignans contents, and also influences consumer preferences. In East Asia, black sesame seed is used in the treatment and the prevention of various diseases. However, in sesame, little is known about the establishment of the seed coat color, and only one gene has been reported to control black pigmentation. This study provides an overview of developing seeds transcriptome of two varieties of sesame “Zhongfengzhi No.1” (white seed) and “Zhongzhi No.33” (black seed) and shed light on genes involving in black seed formation. Until eight days post-anthesis (DPA), both the seeds of the two varieties were white. The black sesame seed turned to yellow between 9 and 11 DPA and then black between 12 and 14 DPA. The black and white sesame showed similar trend-expressed genes with the numbers increased at the early stages of seed development. The differentially expressed genes (DEGs) number increased with seed development in the two sesame varieties. We examined the DEGs and uncovered that more were up-regulated at the early stages. The DEGs between the black and white sesame were mainly enriched in 37 metabolic pathways, among which the flavonoid biosynthesis and biosynthesis of secondary metabolites were dominants. Furthermore, we identified 20 candidate genes associated with pigment biosynthesis in black sesame seed, among which 10 were flavonoid biosynthesis and regulatory genes. These genes also include isochorismate and polyphenol oxidase genes. By comparing the phenotypes and genes expressions of the black and white sesame seed at different development stages, this work revealed the important role of 8–14 DPA in black pigment biosynthesis and accumulation. Moreover, it unfolded candidate genes associated with black pigmentation in sesame. These findings provide a vast transcriptome dataset and list of genes that will be targeted for functional studies related to the molecular mechanism involved in biosynthesis and regulation of seed coat color in sesame.


Zootaxa ◽  
2020 ◽  
Vol 4861 (2) ◽  
pp. 257-269
Author(s):  
EDUARDO LÓPEZ

During a survey on the benthic invertebrates of the upper reaches of river Eo (Galicia, NW Spain), a dense population of epigean asellid isopods were detected in the source of the river. After examination, these specimens resulted to belong to a new species of the genus Bragasellus Henry & Magniez, 1968. The new species comes to fill a geographical gap between the two alleged ancestral areas of the genus and is characterized by its appendix masculina (male pleopod II endopod), which bears a short but distinct cylindrical cannula and lacks basal process. Other characteristic traits are uniform black pigmentation in live specimens, pereopod I dactylus shorter than the palm of the propodus, smooth (instead of plumose) texture of the marginal setae on male pleopod I exopod, and pleopod III exopod with a straight internal side. In this job, description of the new taxon is provided, as well as a key to all the known species belonging to the genus. 


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