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1.
BACKGROUND: On December 26, 2004, the biggest earthquake for 40 years, measuring 9.0 on the Richter scale, triggered a tsunami that pounded the coastal areas of South Asia and East Africa. The effects of the tsunami on skin conditions have not been evaluated. OBJECTIVE: To determine the influence of the tsunami on skin conditions by evaluating the skin problems of patients presenting at hospitals after the tsunami. METHODS: Between 5 and 25 January 2005, two dermatologists evaluated patients who complained of skin problems at an outpatient clinic and emergency room of a general hospital in Banda Aceh, Aceh Province, Indonesia. RESULTS: The total number of patients that presented during the study period was 235 (131 males and 104 females), and they had a total of 265 skin problems. In terms of age distribution, most subjects were in their fourth decade (23.0%), followed by the third (22.6%) and fifth decade (16.6%). The most prevalent skin problems were infections-infestations (32.5%), followed by eczemas (29.8%) and traumatic skin disorders (29.4%). In males, traumatic skin disorders were most common. The great majority of infection-infestation cases involved superficial fungal infections. Contact dermatitis accounted for three-quarters of eczema cases, and mainly involved the arms (40.0%) and legs (27.1%). The majority of traumatic skin disorders were lacerations, punctures and penetrations, and the feet (44.7%) and hands (18.8%) were most frequently affected. CONCLUSIONS: Unhygienic conditions, exposure to a hazardous environment and contact with various objects during and after the tsunami probably increased the prevalence of infections-infestations, traumatic skin disorders and contact dermatitis. To prevent these problems and associated secondary bacterial infections, health-related education and early medical management are required.  相似文献   
2.
Thyrotropin releasing hormone [L-proglutamyl-L-histidyl-L-proline amide (TRH)], a tripeptide with molecular weight of 362 and a pKa of 6.2, was used as a model peptide for in vitro passive and iontophoretic diffusion cell studies using excised dorsal nude mouse skin. The results indicate that both the charged and uncharged TRH fluxes across the excised tissue were greater than those obtained by passive diffusion alone. The steady-state flux of both the uncharged and charged TRH was directly proportional to the applied current density, with flux being greater for the uncharged TRH. Additional studies on the transport of methylene blue indicate that transport may be occurring through pores, and that positive ions are preferentially passed through the skin. These results imply that the steady-state flux of TRH is primarily due to a direct, electrically induced ion motion and convection. A practical implication of these results is that it may be possible to enhance and control the transdermal delivery of peptides.  相似文献   
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Human chromosome 11p15.5 and distal mouse chromosome 7 include a megabase-scale chromosomal domain with multiple genes subject to parental imprinting. Here we describe mouse and human versions of a novel imprinted gene, IMPT1 , which lies between IPL and p57 KIP2 and which encodes a predicted multi-membrane-spanning protein similar to bacterial and eukaryotic polyspecific metabolite transporter and multi- drug resistance pumps. Mouse Impt1 and human IMPT1 mRNAs are highly expressed in tissues with metabolite transport functions, including liver, kidney, intestine, extra-embryonic membranes and placenta, and there is strongly preferential expression of the maternal allele in various mouse tissues at fetal stages. In post-natal tissues there is persistent expression, but the allelic bias attenuates. An allelic expression bias is also observed in human fetal and post-natal tissues, but there is significant interindividual variation and rare somatic allele switching. The fact that Impt1 is relatively repressed on the paternal allele, together with data from other imprinted genes, allows a statistical conclusion that the primary effect of human chromosome 11p15.5/mouse distal chromosome 7 imprinting is domain-wide relative repression of genes on the paternal homolog. Dosage regulation of the metabolite transporter gene(s) by imprinting might regulate placental and fetal growth.   相似文献   
6.
Recently, in-vitro maturation (IVM) of immature human oocytes recovered from non-stimulated follicles has been applied in the treatment of infertility. However, in previous reports, very few embryos cultured in conventional medium have reached the expanded blastocyst stage following in-vitro maturation and fertilization (IVM/IVF). The objective of this study was to investigate whether the developmental competence of human embryos following IVM/IVF could be enhanced by the use of a human ampullary cell co-culture system. Immature human oocytes were aspirated from small follicles at Caesarean section and then cultured in medium containing human menopausal gonadotrophin for 36 to 48 h, followed by insemination. Zygotes were randomly cultured either in conventional culture medium alone or in the co-culture system. Of 48 embryos cultured in conventional medium alone, all arrested at the 2-16- cell stage on day 3 after insemination. Of 46 embryos cultured in the co-culture system, 26 embryos (56.5%) arrested at the 2-16-cell stage. Six embryos (13%) developed to the morula stage. Fourteen embryos (30.4%) developed to expanded blastocysts and two blastocysts were hatching on day 7 after insemination. We conclude that co-culture significantly enhances the development of blastocysts in embryos resulting from IVM/IVF.   相似文献   
7.
To determine whether antibodies to the B oligomer of pertussis toxin (PT) were present in patients diagnosed with pertussis or vaccinees who had received diphtheria-tetanus-whole-cell pertussis vaccine, we analyzed serum samples from 5 patients and 10 vaccinees by both enzyme-linked immunosorbent assay (ELISA) and Western immunoblotting techniques. Antibodies to the B oligomer were detected by ELISA in all samples containing antibodies to holotoxin. Western immunoblotting procedures were less efficient than ELISA techniques for detecting antibodies to the B oligomer. Antibodies which inhibit the ability of the B oligomer to agglutinate erythrocytes were detected in purified human immunoglobulin preparations. In addition, serum samples containing antibodies to PT inhibited the binding of purified B oligomer and holotoxin to a 165-kDa glycoprotein which has been considered a potential PT receptor in Chinese hamster ovary (CHO) cells. These results suggest that antibodies to the B oligomer contribute to the human serologic response to PT, but their detection and characterization require appropriate methods.  相似文献   
8.
To identify the neutralizing epitopes on the S1 subunit (A promoter) of pertussis toxin, we characterized anti-S1 monoclonal antibodies (MAbs) X2X5, 3CX4, and 6FX1. We confirmed by immunoblot analysis that these MAbs bind to the S1 subunit and not to the B oligomer of pertussis toxin and that they recognize different epitopes by a competitive binding enzyme-linked immunosorbent assay. These MAbs had differential abilities to neutralize the lymphocytosis-promoting factor activity of pertussis toxin in mice: 3CX4 and 6FX1 had partial neutralizing abilities, while MAb X2X5 had none. With these MAbs, the epitopes on the S1 subunit were examined by using trypsinized S1 peptides, recombinant truncated S1 molecules, and synthetic peptides. The non-neutralizing MAb X2X5 bound in immunoblots to tryptic peptides of various sizes as small as 1.5 kilodaltons; the neutralizing MAbs 3CX4 and 6FX1 bound only to a 24-kilodalton tryptic peptide band. Immunoblot studies with recombinant truncated S1 molecules demonstrated that amino acid residues 7 to 14 and 15 to 26 play an important role in the binding of neutralizing MAbs and the non-neutralizing MAb, respectively. The binding of these MAbs was not dependent upon the presence of C-terminal amino acid residues 188 to 234. To further define B-cell epitopes, the binding of the MAbs we tested to synthetic peptides representing the entire S1 subunit were examined. Neutralizing MAbs 3CX4 and 6FX1 bound to none of these peptides, further suggesting that these MAbs recognize conformational epitopes. The non-neutralizing MAb X2X5 bound to peptides 11 to 26 and 16 to 30, demonstrating that the major antigenic determinant recognized by this MAb is a linear epitope located within residues 16 to 26.  相似文献   
9.
Mutations in the gene encoding the Survival Motor Neuron (SMN) protein are responsible for autosomal recessive proximal spinal muscular atrophy (SMA). SMN orthologues have been identified in the nematode worm Caenorhabditis elegans and the yeast Schizosaccharomyces pombe but, to date, no human paralogues have been described. Here we describe identification and characterization of an SMN-related protein (SMNrp) gene that encodes a novel protein of 239 amino acids, which has recently been identified as a constituent of the spliceosome complex and designated SPF30. Significant similarity to the SMN protein is apparent only within a central region of SMNrp that represents a tudor domain. The SMNrp/SPF30 gene has been mapped to chromosome 10q23. It is differentially expressed, with abundant levels in skeletal muscle. An exclusively nuclear localization for SMNrp in cultured cells and muscle sections was revealed using GFP fusion constructs and thereafter confirmed with a polyclonal antibody raised against SMNrp. Overexpression of SMNrp as a fusion protein in HeLa cells in culture induced dose-dependent apoptosis with positive TUNEL staining. In addition to a possible role for this protein as a pro-apoptotic factor, SMN and its related protein share significant similarities in sequence and cellular function.   相似文献   
10.
Background:  Control of mRNA stability is an essential regulatory process in eukaryotic gene expression. HuR, a 3'UTR mRNA binding protein, can protect AU-rich mRNA from degradation in response to stresses. PlGF, an angiogenic growth factor, contains two consensus AU-rich sites suggesting that under normal conditions HuR may protect PlGF mRNA from degradation. Trophoblast expression of PlGF is significantly decreased in preeclampsia and by hypoxia in vitro . We hypothesize that decreased levels of cytoplasmic HuR may contribute to decreased PlGF expression in hypoxic and preeclamptic trophoblast.
Methods:  Western blots were used to determine relative effects of in vitro hypoxia on HuR protein expression and subcellular localization in trophoblast. Immunohistochemistry was used to compare HuR expression patterns in trophoblast of preeclamptic and normal placentae.
Results:  Cytoplasmic expression of HuR was decreased 1.4 fold in the cytoplasm and 1.2 fold in the nucleus of JEG3 cells. A shift in HuR was more apparent in primary trophoblast with a greater than 2-fold decrease in the cytoplasm and a 1.4 fold decrease in the nucleus following 24 hr of hypoxia. Immunohistochemical analyses detected HuR expression in near term trophoblast in situ . However, this technical approach did not detect a significant change in HuR expression between normal and preeclamptic trophoblast.
Conclusions:  HuR expression is decreased in hypoxic trophoblast, at least in vitro , which may provide a causal link to decreased PlGF mRNA expression. Down regulation of trophoblast PlGF expression is thought to contribute to the pathophysiology associated with preeclampsia including the relative lack of perfusion of the placenta and systemic renal effects.  相似文献   
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