Physiological and ultrastructural responses of the brown seaweed Undaria pinnatifida to triphenyltin chloride (TPTCL) stress.

Triphenyltin chloride (TPTCL) is a well-known marine pollutant that may constitute major environmental threats to seaweed mariculture. In the present study, the toxic effects of TPTCL on physiology and ultrastructure of cultivated sporophytes of Undaria pinnatifida were investigated under different TPTCL concentrations ranging from 0 to 100 µg L-1. Significant negative effects of increased TPTCL concentration were detected in the relative growth rates, survival percentages and chlorophyll a contents of young and adult sporophytes. Low TPTCL concentrations could significantly stimulate the activities of enzymes related to nitrogen metabolism. The chloroplast, mitochondria and nucleus inside cells were greatly damaged by TPTCL. Meanwhile, significant increases of electron dense deposits and physodes were found. Additionally, young sporophytes exhibited greater tolerance to TPTCL stress than adult sporophytes. The results of this study indicate that coastal TPTCL pollution could reduce the productivity and quality of cultivated U. pinnatifida.

[Effects of grass cover combined with different fertilization regimes on soil nutrients and enzyme activities in apple orchard in Weibei dryland, China.] / æ¸­åŒ—æ—±åœ°è‹¹æžœå›­ç”Ÿè‰è¦†ç›–ä¸‹ä¸åŒè‚¥æ–™é æ–½å¯¹åœŸå£¤å »åˆ†å’Œé ¶æ´»æ€§çš„å½±å“.

The split-plot design was adopted in this experiment, with main treatments of grass cover and control and sub-treatments included four fertilization regimes: no fertilization, CK; manure, M; N,P and K fertilizer, NPK; and NPK fertilizer combined with manure, MNPK. Microplate fluorimetry was used to study the effects of grass cover combined with different fertilization regimes on the enzyme activities in apple orchard. The results showed that after mowing the grass (the residues were left on the soil surface as mulch), the soil water content, available P, nitrite nitrogen and the activities of ßX, NAG, ßG, CBH were increased compared to the control, with no significant differences for total nitrogen, soil organic carbon, and AKP activity. For grass cover treatment, the total nitrogen, soil organic carbon, and the activities of ßX, NAG, ßG, CBH, AKP were both improved before and after mowing the grass. However, the soil water content, available phosphorus, and nitrate nitrogen of grass cover treatment were lower than that of the control before mowing the grass. Under grass cover condition, the total nitrogen, available P, and soil organic carbon of M and MNPK were higher than that of CK and NPK in both before and after mowing the grass periods, with the activities of ßX, NAG, ßG, CBH, AKP of MNPK higher than that of NPK. Under the control condition, the available P, soil organic carbon (SOC), nitrite nitrogen, total nitrogen and the activities of ßG, CBH, AKP of MNPK higher than that of CK and NPK before and after mowing the grass. Redundancy analysis showed that the activities of soil enzymes were significantly correlated with the soil nutrients, and could reflect the soil fertility. Thus, grass cover combined with MNPK significantly increased the soil nutrient contents and soil enzyme activities, and was an important practice to prevent the decrease of soil fertility and benefit the sustainability of local apple industry.

Differences in the melanosome distribution within the epidermal melanin units and its association with the impairing background of leukoderma in vitiligo and halo nevi: a retrospective study.

Skin color is determined by the number of melanin granules produced by melanocytes that are transferred to keratinocytes. Melanin synthesis and the distribution of melanosomes to keratinocytes within the epidermal melanin unit (EMU) within the skin of vitiligo patients have been poorly studied. The ultrastructure and distribution of melanosomes in melanocytes and surrounding keratinocytes in perilesional vitiligo and normal skin were investigated using transmission electron microscopy (TEM). Furthermore, we performed a quantitative analysis of melanosome distribution within the EMUs with scatter plot. Melanosome count within keratinocytes increased significantly compared with melanocytes in perilesional stable vitiligo (P < 0.001), perilesional halo nevi (P < 0.01) and the controls (P < 0.01), but not in perilesional active vitiligo. Furthermore, melanosome counts within melanocytes and their surrounding keratinocytes in perilesional active vitiligo skin decreased significantly compared with the other groups. In addition, taking the means-standard error of melanosome count within melanocytes and keratinocytes in healthy controls as a normal lower limit, EMUs were graded into 3 stages (I-III). Perilesional active vitiligo presented a significantly different constitution in stages compared to other groups (P < 0.001). The distribution and constitution of melanosomes were normal in halo nevi. Impaired melanin synthesis and melanosome transfer are involved in the pathogenesis of vitiligo. Active vitiligo varies in stages and in stage II, EMUs are slightly impaired, but can be resuscitated, providing a golden opportunity with the potential to achieve desired repigmentation with an appropriate therapeutic choice. Adverse milieu may also contribute to the low melanosome count in keratinocytes.

rhCSF3 accelerates the proliferation of human melanocytes in culture through binding CSF3R and the expression of CSF3R transcripts.

Melanogenic paracrine and autocrine cytokine networks have recently been discovered in vitro between melanocytes and other types of skin cells. Granulocyte colony-stimulating factor receptor (CSF3R) controls the survival, proliferation and differentiation of many kinds of cells, including neutrophils. To understand the function of CSF3R and recombinant human granulocyte colony-stimulating factor (rhCSF3) on melanocyte proliferation, this study compared the expression of CSF3R and the effects of rhCSF3 in primary human melanocytes, neutrophils and HEL 92.1.7 cells. The results show that CSF3R is localized in the cytoplasm and on cell membranes of melanocytes and neutrophils. The percentage of CSF3R(+) melanocytes was higher than CSF3R(+) HEL 92.1.7 cells, but was lower than CSF3R(+) neutrophils. Both CSF3R mRNA and CSF3R protein levels in melanocytes were higher than in HEL 92.1.7 cells, but were lower than in neutrophils. Treatment with rhCSF3 increased the proliferation of human melanocytes, but not their tyrosinase activity. Transcripts of CSF3R in human melanocytes, M14, A375 melanoma and A431 squamous cell carcinoma cells were also detected. Expression of the CSF3R V3 transcript was lower in melanocytes than in M14, A375 melanoma and A431 squamous cell carcinoma cells. In conclusion, rhCSF3 can promote melanocyte proliferation through CSF3R without affecting tyrosinase activity.

A comparative study of mitochondrial ultrastructure in melanocytes from perilesional vitiligo skin and perilesional halo nevi skin.

Vitiligo and halo nevi are both pigmentary disorders of the skin characterized by the acquired loss of functional epidermal melanocytes manifesting as white macules and patches. The cellular mechanism(s) and biochemical changes that result in the appearance of these two types of achromic lesions are still uncertain; and the relationship between vitiligo and halo nevi has been in dispute. In this study, we investigated the ultrastructure of mitochondria in melanocytes and in keratinocytes from perilesional vitiligo skin and from perilesional halo nevi skin using Transmission Electron Microscopy. Furthermore, we performed a quantitative analysis of mitochondrial morphology through a stereological study. As previously reported, we found that melanocytes from perilesional active vitiligo skin were loosely connected with their surroundings by their retracted dendrites. The surface density and the volume density of mitochondria in melanocytes and in keratinocytes from perilesional vitiligo skin are increased significantly compared with the controls, especially in active vitiligo. In contrast, there are no significant differences in mitochondria in melanocytes and in keratinocytes from perilesional halo nevi skin compared with the controls. In summary, the tendency of different morphologic alterations in mitochondria from perilesional vitiligo skin and from perilesional halo nevi skin reflect heterogeneous backgrounds between the two diseases, revealing that vitiligo and halo nevi may have separate pathogenic mechanisms. These findings may help elucidate the relationship of these two diseases and their underlying mechanisms.

Stevens-Johnson Syndrome and toxic epidermal necrolysis: a multi-aspect comparative 7-year study from the People's Republic of China.

BACKGROUND: Stevens-Johnson Syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare but severe cutaneous drug reactions. They are differentiated based on the fraction of the body surface area affected. Optimal therapy for SJS and TEN is a controversial issue. OBJECTIVE: We compared the treatments given to and the clinical outcomes of 39 cases of SJS and 48 cases of TEN seen at a single institution between January 2007 and December 2013 for better understanding of the clinical characteristics and development of the two conditions. METHODS: Demographic data, clinical characteristics, treatments given, and therapeutic responses observed were retrospectively collected. RESULTS: The incidence rates of hypoproteinemia and secondary infections are significantly higher in TEN than in SJS (P=0.001 and P=0.002, respectively). The corticosteroid dose did not influence the time from the initiation of therapy to control of the lesions in SJS, but increasing the dosage of corticosteroids progressively decreased the time from the initiation of therapy to control of the lesions in TEN. With increases in the utilization ratio of intravenous immunoglobulin (IVIG), the length of the hospital stay became shorter, whereas the time from the initiation of therapy to control of the lesions remained the same in SJS. However, for TEN, both the length of the hospital stay and the time from the initiation of therapy to control of the lesions became shorter with increases in the utilization ratio of IVIG. CONCLUSION: SJS and TEN are two variants of the same spectrum, and they differ from each other not only in the severity of epidermal detachment but also in other clinical parameters and their distinct clinical courses. Thus, differential treatment of both conditions may have benefits for their prognosis.

Transcript expression profiles of Takifugu rubripes spermatozoa and eggs by expressed sequence tag analysis.

Two cDNA libraries from Takifugu rubripes spermatozoa and eggs were constructed and a total of 620 expressed sequence tag (EST) clones were generated from the two libraries: 300 clones are from the spermatozoa library and 320 clones are from the eggs library. The most abundant cDNA clones in the two libraries were identified. A total of 207 'contigs' (or single) EST clones were found to share significant sequence identity with known sequences in the GenBank database, representing at least 51 different genes. In order to understand the two types of germ cells further, the expression profiles of the identified clones in these cDNA libraries were analyzed. Furthermore, the presence of specific messenger RNAs in the spermatozoa and eggs has been demonstrated with BLAST analysis; the spermatozoa and egg library can supply unique and novel cDNA sequences in the Takifugu rubripes EST project. Another aim of this study is to identify cDNA clones that can be used as molecular markers for the analysis of the spermatogenesis and oogenesis in Takifugu rubripes. Six potential clones (S1-3 from spermatozoa and E1-3 from eggs) were selected to analyze their expression patterns by reverse transcription (RT)-PCR analyses. Half of these showed a specific expression in the expected tissue. Two of the clones were found by RT-PCR and in situ hybridization to be expressed specifically in the testis or ovary, and they maybe suitable molecular markers for the analysis of spermatogenesis and oogenesis.