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Objective To investigate the relationship between iodine nutritional status and thyroid hormone levels,and to provide a guideline for monitoring iodine nutrition and thyroid function.Methods A crosssectional survey was performed by randomly selecting 341 samples (health pregnant women with a first child) from the Second People's Hospital of Guiyang,Bihai Community Medical Center and Jinhuayuan Community Center from October 2015 to September 2016.Levels of serum hormones and antibodies relative to throid of pregnant women in Guanshan Lake District of Guiyang at different pregnant times,which included throid stimulating hormone (TSH),free three triiodothyronine (FT3),free thyroxine (FT4),thyroid peroxidase antibody (TPOAb),and thyroglobulin antibody (TgAb),were measured by the electrochemical luminescence method,and urinary iodine levels were measured by heat digestion.Results The median urinary iodine of pregnant women at early,middle and late stages (T1,T2 and T3 stages) were 191.8,198.9 and 214.5 μg/L,respectively.FT3 increased first and then decreased during pregnancy.Levels of FT3 in the T2 stage were significandy higher than those in T1 and T3 stages (FT3 medians at the three stages were 4.49,4.83 and 4.57 pmol/L),and the differences were statistically significant (P ＜ 0.05).FT4 levels decreased during pregnancy (FT4 medians at the three stages were 16.32,14.65 and 13.22 pmol/L),and the differences among the three groups were statistically significant (H =67.517,P ＜ 0.01).Statistically significant differences were not found in the TSH levels among the three groups ~SH medians at the three stages were 2.05,2.01 and 2.39 mU/L,H =1.297,P ＞ 0.05).The medians of TPOAb and TgAb during T2 stage (9.60 and 19.02 U/ml) were significantly lower than those of other groups (18.92 and 24.75 U/ml at stage T1,and 13.46 and 22.06 U/ml at stage T3),and the differences were statistically significant (P ＜ 0.05).TSH levels were consistent with urinary iodine levels.TSH levels in the excessive iodine group (urine iodine:250 ～ 499 μg/L,2.54 mU/L) were significantly higher than those in the adequate iodine group (urine iodine:150 ～ 249 μg/L,1.97 mU/L) and deficient iodine group (urine iodine:＜ 150 μg/L,1.91 mU/L),and the differences were statistically significant (P ＜ 0.05).No correlations were found between levels of FT3,FT4,TPOAb,TgAb and levels of the urinary iodine.There was a significant positive correlation between urinary iodine levels and TSH levels (rs =0.180,P ＜ 0.01).The incidence of abnormal thyroid function in pregnant women was 29.33％ (100/341),which was composed of clinical hypothyroidism (accounting for 0.88％,3/341),subclinical hypothyroidism (accounting for 25.51％,87/341),low T4 level (accounting for 1.76％,6/341),clinical hyperthyroidism (accounting for 0.59％,2/341),subclinical hyperthyroidism (accounting for 0.59％,2/341),and TPOAb positive and TgAb positive (accounting for 12.61％,43/341).These abnormalities occurred mainly in the T1 and T3 stages.The prevalence of subclinical hypothyroidism increased with increasing of urinary iodine level,and the difference was statistically significant (x2 =11.269,P ＜ 0.05).Conclusion There is a positive correlation between pregnancy iodine nutritional status and its TSH level,so it is important to monitor the level of urinary iodine during pregnancy and to screen the thyroid function and antibodies in the early and middle time of pregnancy.
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Objective To investigate the changes of serum thyroid peroxidase(TPOAb)and thyroglobulin antibody(TGAb)and their relationship with thyroid function in pregnant women during different gestation period Methods Totally 341 cases of primiparae were selected from October 2015 to September 2016 and levels of se-rum thyrotropin(TSH),free triiodothyronine(FT3),free thyroxine(FT4),thyroid peroxidase antibody(TPOAb) and thyroglobulin antibody(TgAb)were measured by electrochemiluminescence. Results The prevalence of thy-roid dysfunction and positive serum thyroid autoantibodies were 13.2%and 12.61%respectively,which mainly oc-curred in early and middle pregnancy. Thyroid dysfunction in subjects included hypothyroidism(0.59%),subclini-cal hypothyroidism(7.92%),low T4 hyperlipidemia(3.23%),hyperthyroidism(0.88%)and subclinical hyper-thyroidism(0.59%). The positive rate of TPOAb was significantly higher than that of TgAb(10.85% vs. 4.99%, P<0.01). The positive rate of TPOAb in women with thyroid disfunction was significantly higher than that in those with normal thyroid function(44.44%vs. 5.74%,P<0.01). TSH level of TPOAb positive subjects was higher than that of TPOAb negative ones(P<0.05,P<0.01);TSH level of TPOAb positive subjects with thyroid dysfunction were significantly higher than those of TPOAb negative subjects and TPOAb positive pregnant women but with nor-mal thyroid function(P < 0.01). The hypothyroidism prevalence rate of TPOAb positive subjects was significantly higher than that of TPOAb negative subjects in early and middle stage of pregnancy (P < 0.01). The prevalence rates of subclinical hypothyroidism ,low T4 hyperlipidemia and clinical hypothyroidism were significantly higher in TPOAb positive pregnant women(29.17%,20.83% and 8.33%)than those in TPOAb negative pregnant women (P < 0.01). Conclusions Thyroid dysfunction is closely related to positive status of TPOAb and TgAb in pregnancy,which could influence the outcome of pregnancy and the development of offspring. Since levels of TSH, FT3 and FT4 could not fully reveal thyroid function ,it is necessary to monitor the status of TPOAb and TgAb as early as possible for the early diagnosis and treatment of thyroid disease in pregnancy.
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Objective To investigate the changes of serum thyroid peroxidase(TPOAb)and thyroglobulin antibody(TGAb)and their relationship with thyroid function in pregnant women during different gestation period Methods Totally 341 cases of primiparae were selected from October 2015 to September 2016 and levels of se-rum thyrotropin(TSH),free triiodothyronine(FT3),free thyroxine(FT4),thyroid peroxidase antibody(TPOAb) and thyroglobulin antibody(TgAb)were measured by electrochemiluminescence. Results The prevalence of thy-roid dysfunction and positive serum thyroid autoantibodies were 13.2%and 12.61%respectively,which mainly oc-curred in early and middle pregnancy. Thyroid dysfunction in subjects included hypothyroidism(0.59%),subclini-cal hypothyroidism(7.92%),low T4 hyperlipidemia(3.23%),hyperthyroidism(0.88%)and subclinical hyper-thyroidism(0.59%). The positive rate of TPOAb was significantly higher than that of TgAb(10.85% vs. 4.99%, P<0.01). The positive rate of TPOAb in women with thyroid disfunction was significantly higher than that in those with normal thyroid function(44.44%vs. 5.74%,P<0.01). TSH level of TPOAb positive subjects was higher than that of TPOAb negative ones(P<0.05,P<0.01);TSH level of TPOAb positive subjects with thyroid dysfunction were significantly higher than those of TPOAb negative subjects and TPOAb positive pregnant women but with nor-mal thyroid function(P < 0.01). The hypothyroidism prevalence rate of TPOAb positive subjects was significantly higher than that of TPOAb negative subjects in early and middle stage of pregnancy (P < 0.01). The prevalence rates of subclinical hypothyroidism ,low T4 hyperlipidemia and clinical hypothyroidism were significantly higher in TPOAb positive pregnant women(29.17%,20.83% and 8.33%)than those in TPOAb negative pregnant women (P < 0.01). Conclusions Thyroid dysfunction is closely related to positive status of TPOAb and TgAb in pregnancy,which could influence the outcome of pregnancy and the development of offspring. Since levels of TSH, FT3 and FT4 could not fully reveal thyroid function ,it is necessary to monitor the status of TPOAb and TgAb as early as possible for the early diagnosis and treatment of thyroid disease in pregnancy.
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Objective To evaluate the changes to mitochondrial ultrastructure in melanocytes of perilesional skin from patients with vitiligo.Methods Skin specimens were obtained from the perilesional area (0.5-1 cm distal to vitiligo lesions) of 10 patients with progressive vitiligo and 10 patients with stable vitiligo,as well as from the normal skin of 10 healthy volunteers.The morphology of melanocytes was observed by using transmission electron microscopy (TEM).Besides,stereological parameters of mitochondria,such as volume density (Vv),surface density (Sv) and numerical density (Nv),were measured.Results In melanocytes from the healthy controls,there were a large number of melanosomes with the number of melanosomes per melanocyte being 28.57± 3.21,which were mainly at stage Ⅲ and Ⅳ; mitochondria with normal structure and densely packed cristae were regularly arranged; autophagosomes were seen occasionally.Compared with the melanocytes from healthy controls,there was an obvious decrease in the number of melanosomes (especially stage Ⅲ melanosomes) in melanocytes from the perilesional skin of patients,with the number of melanosomes per melanocyte being 22.00 ± 6.16 (P ＜ 0.05) and 17.43 ± 6.24 (P ＜ 0.05) in patients with progressive vitiligo and stable vitiligo,respectively.TEM also showed disorganized or disrupted mitochondria in various shapes and sizes,most of which were swelling with obscure cristae and vacuolization,in melanocytes from the perilesional skin,and no autophagy was observed.The three stereological parameters were significantly different between the three groups of tissue specimens (all P ＜ 0.05),with the Nv,Vv and Sv of mitochondria being (7.194 ± 1.434) μm-3,(4.8 ± 1.2) ％,(2.42 ± 0.86) μ m-1 respectively in melanocytes from the healthy controls,(4.055 ± 0.906) μm-3,(7.4 ± 2.1)％,(3.58 ± 1.15)μm-1 respectively from patients with progressive vitiligo,(5.311 ± 0.873) μm-3,(6.5 ± 1.4)％,(2.82 ± 0.94) μm-1 respectively from patients with stable vitiligo.Conclusions Mitochondria are injured in melanocytes from perilesional skin of patients with vitiligo,and the degree of injury is more intense in progressive vitiligo than in stable vitiligo.
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Objective To measure the expression of granulocyte colony-stimulating factor receptor (G-CSFR) in human melanocytes and to evaluate the biologic effect of recombinant human granulocyte colony-stimulating factor (rhG-CSF) on human melanocytes.Methods Melanocytes were obtained from circumcision specimens of healthy males,and neutrophils were isolated from heparin-andcoagulated peripheral blood of healthy human followed by a primary culture.Then,the melanocytes in third passage were cultured with or without the presence of various concentrations (200,400,600,800 μg/L) of rhG-CSF for 72 hours.The growth and morphology of melanocytes were observed.Flow cytometry was performed to detect the expression of G-CSFR in untreated human melanocytes,neutrophils and erythroleukemia cells (HEL 92.1.7).Western blot and reverse transcription PCR (RT-PCR) were carried out to measure the expression of G-CSFR protein and mRNA respectively in the neutrophils,HEL 92.1.7 cells,treated or untreated human melanocytes.Methyl thiazolyl tetrazolium (MTT) assay was performed to evaluate the proliferation,and dopa-oxidation assay to estimate the tyrosinase activity,of treated melanocytes.Results The expression rate of G-CSFR was 76.81％ ± 10.70％ in human melanocytes,significantly higher than that in the HEL 92.1.7 cells (2.53％ ± 1.54％,P ＜ 0.01 ),but lower than that in the neutrophils (85.76％ ± 15.71％,P ＜ 0.05).Both G-CSFR protein and mRNA were expressed in melanocytes,and there was no significant differences in the expression level of G-CSFR protein and mRNA among melanocytes treated with different concentrations of rhG-CSF (both P ＞ 0.05).The expression levels of G-CSFR protein and mRNA in the melanecytes were significantly higher than those in the HEL 92.1.7 cells (both P ＜ 0.01 ),but lower than those in the neutrophils (P ＜ 0.05 or ＜ 0.01 ).rhG-CSF at 200-800 μg/L displayed a significantly promotive effect on the proliferation of melanocytes (P ＜ 0.01 or ＜ 0.05 ),and the effect was in a dose-dependent manner when rhG-CSF ranged from 200 to 600 μg/L (P ＜ 0.01 ).The rhG-CSF at 600 μg/L and 12-O-tetradecanoyl-phorbol-13-acetate (TPA) at 20 μg/L showed an equivalent effect on the proliferation of melanocytes (164.04％ ± 13.0％ vs.165.62％ ± 10.6％,P ＞ 0.05).However,rhG-CSF from 200 to 800 μg/L had no significant impact on the tyrosinase activity of melanocytes (all P ＞ 0.05 ).Conclusions G-CSFR is expressed in human melanocytes. rhG-CSF can promote the proliferation of cultured human melanocytes,but has no obvious influence on the tyrosinase activity of melanocytes.
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A 37-year-old female was admitted to the hospital for an itching and painful subcutaneous nodule with ulceration on the extensor aspect of her left forearm for more than 6 months.The pain was severe,continuous and localized.Systemic and local treatment with antibiotics resulted in no obvious improvement.The lesion had gradually increased in size over the past 6 months and the ulcer had enlarged for 1 month.On examination,a hard infiltrative plaque measuring about 5.5 cm × 4.0 cm with a well-defined margin was seen on the extensor aspect of her left forearm,along with ulceration and some dirty discharge on the surface.The diagnosis of fibrosarcoma,grade Ⅱ was eventually made by a biopsy of the lesion,which revealed increased pigmentation in the basal layer,and tumor tissue was tightly adherent to the epidermis.Dermis and subcutaneous fat layer were infiltrated with various sizes of spindle cells with fine collagen fiber bundles between the cells.Obvious atypia and mitotic figures were easily observed in some of the cells.Immunohistochemical analysis showed moderately positive staining for fibronectin,but negative staining for human melanoma black-45 (HMB45),S100,smooth muscle actin (SMA),Melan-a,high molecular weight cytokeratin (HCK),CD34,CD68 or cytokeratin.Some diseases should be differentiated from this case,including dermatofibrosarcoma protuberans,cutaneous spindle cell squamous carcinoma,atypical fibroxanthoma,malignant fibrous histiocytoma,and so on.
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Objective To investigate the location,fine structure of melanocytes in human fetal scalp hair follicles.Methods The scalp with hair follicles was obtained from a dead fetus of 6 months of age,and divided into two parts.One part was embedded in paraffin,tissue sections were prepared with a width of 7 μm and stained with NKI/beteb,monoclonal antibodies to HMB-45,tyrosinase and tyrosinase-related protein 1(TRP1),respectively.The other part with hair follicles was treated with collagenase type Ⅱ 0.1 g/L and trypsin,then,cell suspension was collected and cultured.After 14-day culture,follicle melanocyte cells (FMC)were separated from keratinocytes by differential trypsinization,and fibroblasts were removed with geneticin.Following three times of pure passage,FMC were seeded and fixed on mica for scanning electron microscopy(SEM)and atomic force microscope(AFM)scanning.Results Histopathological examination showed that NKI/beteb positive cells located at the outer root sheath of human hair follicles,and these cells stained negatively for HMB-45,tyrosinase and TRP1 antibodies.However,in the hair bulb,lots of cells expressed HMB-45,tyrosinase and TRP1 antigens.After fibroblasts and keratinocytes were removed,two kinds of melanocytes remained in the culture:one was small in number and showed abundant melanin,which was lost after subsequent passage;the othgr was large in number and had no melanin initially,but proliferated very rapidly.After three passages,almost all the melanocytes were positive for NKI/beteb.As SEM and AFM showed,most cultured melanocytes appeared fusiform with two(rarely three)dendrites,and the cell body was round or oval with a few melanosomes scattered in but no clear secondary branches on the dendrites.Conclusions The melanocytes in outer root sheath of hair follicles from the fetal scalp are presumed as melanocyte stem cells or their progenies.In vitro,these cells proliferate very rapidly during early phases,but the morphology and function of them still remain immature,which is unfavorable for melanosome transport.
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Objective To investigate the ultrastructural characteristics of amelanotic melanocytes (AMMCs). Methods Individual hair follicles from normal human scalp were digested with collagenase type V, then washed in phosphate buffer saline. Hair-follicle cell suspensions were prepared by trypsin and cultured in a medium suitable for melanocyte growth. The keratinocytes were removed by differential trypsinization. Geneticin (100?g/mL) was used to eliminate contaminating fibroblasts. After 3 passages the cells were trypsinized, washed in phosphate buffer saline, and finally processed for transmission electron microscopy. Results Under transmission electron microscope, the cultured cells were round or oval-shaped with a single large nucleus and double-layered karyotheca. Abundant euchromosome but sparse heterochromosome was observed within the nucleus. There were various organelles in the cytoplasm, including mitochondria, rough endoplasmic reticulum (RER), ribosomes and abundant melanosomes of nearly uniform size. The electronic density granules distributed in a concentric pattern in most of the melanosomes. Colgi complexes were inconspicuous in the cells. Conclusions Compared to epidermal melanocytes, AMMCs from human hair follicles have different ultrastructural characteristics which implies their functional immaturity. AMMCs may serve as the depot for mature melanocytes.
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<p><b>OBJECTIVE</b>To evaluate the effects of aloin, cinnamic acid and 15 other kinds of natural chemicals on the activity of tyrosinase, in order to provide lightening agents in the treatment of hyperpigmentation disorders and cosmetic additives.</p><p><b>METHODS</b>Tyrosinase activity was estimated by measuring the oxidation rate of L-dopa. Inhibition of the enzyme was deduced according to the Lineweaver-Burk plots compared to the control.</p><p><b>RESULTS</b>Cadabine, paeonal, farrerol, evodin, cinnamic acid, aloin and sophorcarpidine had different levels of inhibition of tyrosinase. The inhibitory rates of cinnamic acid (2 mmol/L, 0.5 mmol/L), aloin (2 mmol/L) and the rest were significantly higher than that of hydroquinone (0.5 mmol/L) (P < 0.05).</p><p><b>CONCLUSIONS</b>Tyrosinase activity can be greatly inhibited by cinnamic acid, aloin and sophorcarpidine, of which sophorcarpidine functions as an uncompetitive inhibitor, compared to aloin and cinnamic acid, which are mixed-type inhibitors.</p>
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Humans , Cinnamates , Pharmacology , Cosmetics , Pharmacology , Emodin , Pharmacology , Enzyme Inhibitors , Pharmacology , Hyperpigmentation , Drug Therapy , Monophenol Monooxygenase , Plant Preparations , PharmacologyABSTRACT
The great majority of human diseases are directly or i nd irectly associated with genes. Gene mapping and genetic analysis for human compl ex polygenic disorders has become a hot-spot and the neck of the bottle in the medical genetics research recently. The approach to genome-wide search has pla yed an important role in the respect.
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AIM: Constructing plasmid that expresses human plasminogen kringle 5 gene to analyze the gene expression in E.coli. METHODS: The gene of human plasminogen kringle 5 was inserted into plasmid PBV220 EcoRI site by gene manipulation techniques and was transformed to E.coli TGI. The gene expression was observed by SDS-PAGE. RESULTS: Expression vector PBVK5 was constructed, and human plasmingen kringle 5 gene product was obtained at 42℃ induction. CONCLUSLON: Expression product of human plasminogen kringle 5 gene was soluble form of proteins, and the expression amount was 9.8% in E.coli TGI total proteins.
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We detected varicella-zoster virus (VZV) DNA sequences in bullous lesions and skin biopsies obtained from healed skin lesions in 16 patients with herpes zoster using polymerase chain reaction. A 385 bp VZV DNA fragment was found in all the bullous lesions and in two of six biopsies from the skin lesions healed within two months. No VZV DNA was found in the skin lesions two months after healing in 10 cases of herpes zoster. VZV DNA may be detected at the sites of resolved herpes zoster lesions within short duration.
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Twelve specimens of genital warts were excised from 12 patients and divided into three parts. One part was untreated, the second and the third part were treated with CO_2 laser and microwave respectively. HPV DNA was amplified and detected in 100% of untreated specimens (HPV16 and HPV11 in six patients each), in 83% and 50% of specimens treated with CO_2 laser and microwave respectively. There was a significant difference in the detection rates between untreated and microwave treated specimens (X~2=4.18, P
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Objectives To observe the effects of arsenic trioxide (As2O3) on the cell cycle, differentiation and proliferation of cultured mouse melanoma Cloudman S91 cells. Methods The cell viability was measured by MTT reduction assay. The morphological changes of the cells were examined by Wright-Giemsa staining. Clone forming was carried out to test the proliferation ability. Apoptosis rate and cell cycle of S91 cells were measured by flow cytometry. Results As2O3 in the concentrations of 0.031~0.25 ?mol/L promoted cell growth markedly and blocked the transformation of cells from G0 to G1. As2O3 in the concentrations of 0.5~8.0 ?mol/L inhibited the cell growth and induced apoptosis markedly. Conclusions As2O3 has marked effects on mouse melanoma S91 cells, which include inducing apoptosis and promoting differentiation and proliferation. These effects are dose- and time-dependent.
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Objective To investigate the inhibitory effects of traditional Chinese medicine (TCM) on hypermelanosis and provide experimental evidence for treating skin pigmentary disorders. Methods Five TCMs with strong inhibitory effects on tyrosinase activity were tested. The changes of the number and morphology of melanocytes induced by UVB were observed in the experimental hypermelanosis model (brownish guinea pig). Results Decreased melanocytes and melanin granules were found with the treatment of Poria cocos, Polyporus umbellatus, Cornus officinalis Sieb. et Zucc., Atractylodes macrocephala Koidz., Astoagalus complanatus R. Br. ex Bge. Conclusion There are inhibitory effects on hypermelanosis induced by UVB with the treatment of Poria cocs, Polyporus umbellatus, Cornus officinalis Sieb.et Zucc., Atractylodes macrocephala Koidz., Astoagalus complanatus R. Br.ex Bge.
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Objective To identify the gene mutations and mu tating patterns in a pedigree with X-linked anhidrotic ectodermal dysplasia(EDA)so as to provide a basis for gene diagn osis and genetic counselling of this disorder.Methods Polymerase chain reaction-single s trand conformation polymorphism(PCR-SSCP)analysis and DNA sequencing of amplified prod ucts were performed to screen mutati ons and mutating patterns of EDA1gen e,responsible for EDA pathogenesis,i n a X-linked EDA family of Han people.Results Abnormal single strand bands were found in the amplified fra gments as well of exon 1of EDAgene in t he patients as well as their mothers,the carriers.The DNAsequencing of ampl ified products revealed a point muta tion at nucleotide 404(C→Gtransversion)in the proband compared with that of t he normal controls,which resulted i n the transversion of histidine with glutamine at codon 54in the ectodysplasin-A(H54Q).Meanwhile there were heterozyous double peaks of nucleotide Cand Gat the same position in his mother.Conclusion A missense mutation(404C→G)in exon 1of EDA1gene has been determined in the pedigree with X-linked EDA,which is probably one of the molecular bases of EDA pathogenesis.
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Objective To study CD40 expression on melanocytes induced by IFN-?and its significance. Methods CD40 expression was detected by flow cytometry. The capacity of melanocytes to stimulate T lymphocytes was evaluated by mixed ly mphocyte reaction and the supernatant cytokine levels were determined by ELISA. ResultsHuman melanocytes(MC) cultured in vitro expressed low but detectable CD40 surf ace protein. The surface expression of CD40 was markedly up-regulated by stimul ation with interferon(IFN)-?with different concentrations for 24 hours,48 hour s and 72 hours, respectively. The expression of CD40 was correlated with IFN-? levels after 24 hour incubation. MC underwent a morphologic change with an incre ased capacity to stimulate allogenic lymphocytes to proliferate after IFN-?sti mulation. Optimal enhancement of stimulating index(SI) was observed at an IFN-?concentration of 300 IU/ml after 72 hour treatment. Meanwhile concentrations o f interleukin-12 but not interleukin-8 or 10 were obviously increased in the s upernatants of cultured MC. Furthermore, ligation of CD40 via soluble CD40 ligan d(SCD40L) could enhance CD80 and ICAM-1 expression, which could be blocked by s pecific monoclonal antibody to CD40L. Conclusions Since CD40-CD40L is a pair of important and special costimulating signal, it is of great value to elucidate t he fact that CD40 is functionally expressed on MC, thus for a better understandi ng of MC′s role in cellular immune responses. MC might activate cytotoxic T lym phocyte directly and not via CD4 positive lymphocyte.
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Objective To evaluate the effects of monomers of aloin, cinnamic acid and sophocarpidine on the acitivity of tyrosinase,so as to provide depigmenting agents in the treatment of hyperpigmentation disorders and cosmetics additives as well. Methods Tyrosinase activity was estimated by measuring the oxidation rate of DL dopa. The inhibitory pattern of each monomers was determined according to their Lineweaver Burk curve as compared to controls. Results Aloin,cinnamic acid and sophocarpidine down regulated the activity of tyrosinase. The inhibitory rates were significantly higher in cinnamic acid group(2 mmol/L, 0.5 mmol/L), aloin group (2 mmol/L)and sophocarpidine group than those in hydroquinone group (0.5 mmol/L)(P