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101.
Acanthocephaloides irregularis n. sp. (Arhythmacanthidae) is described from four species of marine fishes in the Gulf of Odessa and Sukhyi Lyman, Ukrainan Black Sea waters, making it the tenth species of the genus. The hosts are the combtooth blenny Parablennius zvonimiri (Kolombatovic) (Blenniidae), the mushroom goby Ponticola eurycephalus (Kessler) (Gobiidae), the tubenose goby Proterorhinus marmoratus (Pallas) (Gobiidae) and the black-striped pipefish Syngnathus abaster Risso (Syngnathidae). The new species is most similar to its closest relative, Acanthocephaloides propinquus (Dujardin, 1845), in proboscis shape and armature (12 longitudinal rows of 5 hooks) and the shape of the trunk, reproductive system and lemnisci, but differs in having randomly distributed trunk spines. These trunk spines are organised in circular rings of individual spines separated by aspinose zones. The new species is also unique in having an anterior trunk collar, a very large triangular cephalic ganglion, nucleated pouches at the posterior end of the proboscis receptacle, and hooks and spines with roots bearing anterior manubria. Valid and invalid species of Acanthocephaloides Meyer, 1932 are listed and a key to all ten species is included.  相似文献   
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103.
A simple approach to synthesize phospholipids to modulate drug release and track lipid-based particulate drug-carriers is described. We synthesized two ether lipids, 1 1-O-hexadecyl-2-pentadenoyl-sn-glycerol-3-phosphocholine (C(31)PC) and 2 1-O-hexadecyl-2-pentadenoyl-sn-glycerol-3-phosphomethanol (C(31)PM), and examined their ability to alter enzymatically triggered release of 6-carboxyfluorescein from liposomes incubated in TRIS buffer or fetal bovine serum solutions. Further, we demonstrated that odd-chain lipids, for example, C(31)PC, could be identified in rat plasma without interference of endogenous lipids. This approach can be adapted to synthesize a variety of lipids for use in developing and optimizing multifunctional drug-carriers.  相似文献   
104.
Previous reports suggest that burn-induced muscle proteolysis can be inhibited by treatment with GSK-3beta inhibitors, suggesting that burn injury may be associated with increased GSK-3beta activity. The influence of burn injury on muscle GSK-3beta activity, however, is not known. We determined the effect of a 30% total body surface full-thickness burn injury in rats on muscle GSK-3beta activity by measuring GSK-3beta activity and tissue levels of serine 9 phosphorylated GSK-3beta, p(Ser9)-GSK-3beta, by Western blot analysis and immunohistochemistry. Because burn-induced muscle wasting is, at least in part, mediated by glucocorticoids, we used dexamethasone-treated cultured muscle cells in which GSK-3beta expression was reduced with small interfering RNA (siRNA) to further assess the role of GSK-3beta in muscle atrophy. Burn injury resulted in a seven-fold increase in GSK-3beta activity in skeletal muscle. This effect of burn was accompanied by reduced tissue levels of p(Ser9)-GSK-3beta, suggesting that burn injury stimulates GSK-3beta in skeletal muscle secondary to inhibited phosphorylation of the enzyme. In addition, burn injury resulted in inhibited phosphorylation and activation of Akt, an upstream regulatory mechanism of GSK-3beta activity. Reducing the expression of GSK-3beta in cultured muscle cells with siRNA inhibited dexamethasone-induced protein degradation by approximately 50%. The results suggest that burn injury stimulates GSK-3beta activity in skeletal muscle and that GSK-3beta may, at least in part, regulate glucocorticoid-mediated muscle wasting.  相似文献   
105.
BACKGROUND: Adenoid cystic carcinoma is a very rare primary pulmonary neoplasm. Cytologic findings of pulmonary washing and brushing in 2 cases of primary bronchial adenoid cystic carcinoma with special histologic features are described, with an emphasis on some points that have not been reported previously, together with the diagnostic pitfalls. CASES: Two cases of primary adenoid cystic carcinoma of the lung were diagnosed on exfoliative cytology. The patients' ages were 55 and 65 years old. Cytologic findings included large and small clusters of small cells in both 2 and 3 dimensions with occasional cystlike spaces containing mucoid material. The cells were arranged in spherical, cylindrical, basaloid and rosettelike arrangements. There were also abundant small and large mucoid globules, cylinders of homogeneous, acellular, mucous material and "cannon balls." Cytoplasmic and intranuclear round inclusions were noted in case 1. Rare findings of nuclear molding were noted. In case 2, chondromyxoid material and a bimorphic population of tumor cells caused diagnostic confusion with other salivary gland-type tumors of the lung. CONCLUSION: These cases showed characteristic cytologic findings of adenoid cystic carcinoma together with rare findings of intracellular and extracellular inclusionlike bodies, myxochondroid material, bimorphic populations and nuclear molding, which can cause diagnostic confusion with other lung tumors.  相似文献   
106.
OBJECTIVE: To describe new cytologic clues to diagnose localized leishmania lymphadenitis (LLL). STUDY DESIGN: The study examined cytologic smears of 170 cases of LLL referred to our department from November 1989 to October 2004. A total of 120 cases were confirmed by detecting Leishman-Donovan (LD) bodies in at least 1 of the cytologic smears and 50 cases, which were histologically confirmed. For comparison we studied cytologic smears of 20 cases of tuberculous lymphadenitis, 20 cases of toxoplasma lymphadenitis and 20 cases of granulomatous lymphadenitis of unspecified causes. RESULTS: Cases were divided into 4 major groups. Cytologic findings in these groups were studied to find highly suggestive clues. Cytologic findings present in most of these groups, but absent or very rare in other granulomatous lymphadenitis, were LD kinetoplasts, plasma cells with different shapes of inclusions and lymphogranular bodies. Rare findings not reported previously were: intraneutrophilic LD bodies, hematoxylin body-like inclusions, fibroblasts, cytoplasmic blebbing and floating parasitophorous vacuoles. CONCLUSION: Despite previous reports emphasizing detecting LD bodies in diagnosing LLL, we present cytologic clues highly suggestive of this self-limited disease when LD bodies cannot be detected or are very few on the smears.  相似文献   
107.
Biological Trace Element Research - Chronic oxidative stress and reactive oxygen species (ROS) in oral cavity as well as acidic pH on dental enamel surface due to the metabolic activities of...  相似文献   
108.
AimDental enamel, the most rigid biological tissue of the tooth known to mankind, is the most integral and fundamental part of the tooth. Enamel matrixes compile 5% of Enamelin peptides and at the time of tooth development, they are considered to effect the formation and elongation of enamel crystallites. ENAM plays critical role in enamel formation. Any changes in ENAM may affect the thickness of enamel and may lead to dental caries. The present study is aimed to evaluate the association of ENAM gene polymorphisms and susceptibility of dental caries development risk.Material and methodsThe present study was carried out on 168 South Indian children, children’s with dental caries were included in study. Written consent was taken from their parents/guardians. Additionally 193 healthy individuals were enrolled as controls. Sampling was done after dental examination of the individuals. Three ENAM gene single nucleotide polymorphisms (SNPs) were rs7671281, rs3796704 and rs12640848 was genotyped to check their role in susceptibility of dental caries development risk.ResultsOut of three SNPs rs7671281 showed statistically significant risk association with dental caries susceptibility in this ethnic population at heterozygous allele CT (OR: 1.939, p = .01865) and with minor allele T (OR: 1.451, p = .001292). SNP rs3796704 showed significant protective association with dental caries in Indian population at heterozygous allele GA (OR: 0.409, p = .0192) and with minor allele A (OR: 0.645, p = .00875). SNP rs12640848 showed significant protective association with dental caries in Indian population at heterozygous allele AG (OR: 3.041, p = .00642) and with minor allele G (OR: 1.478, p = .02184). Preliminary insilico analysis also showed that rs7671281 (Ile648Thr) amino acid change will cause the structural and functional changes in ENAM protein.ConclusionsIn the present study significant association was observed between ENAM gene SNP rs7671281 and dental caries susceptibility in South Indian children. These results suggested that ENAM gene variants may contribute to dental caries in children.  相似文献   
109.
The hepatitis C virus (HCV), the main cause of morbidity and mortality, is endemic worldwide. HCV causes cirrhosis and other complications that often lead to death. HCV is most common in underdeveloped nations, with the highest prevalence rates in Egypt. Tumor suppressor gene (P53) induces the expression of apoptotic antigen-1 gene (APO-1) by binding to its promoter for mediating apoptosis; an important mechanism for limiting viral replication. This study aims at investigating the impact of P53 72 Arg/Pro and APO-1 − 670 A/G polymorphisms on HCV genotype 4a susceptibility. Two hundred and forty volunteers were enrolled in this study and divided into two major groups; 160 HCV infected patient group and 80 healthy control group. HCV patients were classified according to Metavir scoring system into two subgroups; 72 patients in F0/1-HCV subgroup (patients with no or mild fibrotic stages) and 38 patients in F3/4-HCV subgroup (patients with advanced fibrotic stages). Quantification of HCV-RNA by qRT-PCR and fibrotic scores as well as genotyping of HCV-RNA, P53 at 72 Arg/Pro, and APO-1 at − 670 A/G were performed for all subjects. It was resulted that F0/1-HCV patients have significant differences of P53 at 72 (Pro/Pro and Arg/Arg) genotypes and dominant/recessive genetic models as well as APO-1 − 670 A/A genotype and dominant genetic model as compared to F3/4-HCV patients. Moreover, HCV patients have significant differences of P53 at 72 (Pro/Pro) genotype and recessive genetic model as well as APO-1 − 670 A/A genotype and dominant genetic model as compared to those of healthy individuals. Finally, it was concluded that P53 rs 1042522 (Pro/Pro and Arg/Arg) genotypes and APO-1 rs 1800682 A/A genotype may be potentially used as sensitive genetic markers for HCV genotype 4a susceptibility.  相似文献   
110.

Background

Cervical cancer is the second-most-common cause of malignancies in women worldwide, and the oncogenic activity of the human papilloma virus types (HPV) E7 protein has a crucial role in anogenital tumors. In this study, we have designed a therapeutic vaccine based on chitosan nanodelivery systems to deliver HPV-16 E7 DNA vaccine, considered as a tumor specific antigen for immunotherapy of HPV-associated cervical cancer. We have developed a Nano-chitosan (NCS) as a carrier system for intramuscular administration using a recombinant DNA vaccine expressing HPV-16 E7 (NCS-DNA E7 vaccine). NCS were characterized in vitro for their gene transfection ability.

Results

The transfection of CS-pEGFP NPs was efficient in CHO cells and the expression of green fluorescent proteins was well observed. In addition, NCS-DNA E7 vaccine induced the strongest E7-specific CD8+ T cell and interferon γ responses in C57BL/6 mice. Mice vaccinated with NCS-DNA E7 vaccine were able to generate potent protective and therapeutic antitumor effects against challenge with E7-expressing tumor cell line, TC-1.

Conclusions

The strong therapeutic effect induced by the Chitosan-based nanodelivery suggest that nanoparticles may be an efficient carrier to improve the immunogenicity of DNA vaccination upon intramuscular administration and the platform could be further exploited as a potential cancer vaccine candidate in humans.  相似文献   
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