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131.
BACKGROUND: Placental site trophoblastic tumor (PSTT) is a rare and unique form of gestational trophoblastic disease (GTD). This tumor represents a neoplastic transformation of intermediate trophoblastic cells. We document a case of long term remission in a patient with metastatic PSTT. CASE PRESENTAION: A 27-year-old patient with metastatic PSTT was treated with combination therapy (chemotherapy and surgery). Patient is alive after 10 years without any evidence of recurrence. Literature on PSTT was searched using Medline and cross references, and pertinent articles were reviewed. CONCLUSION: With surgery and chemotherapy it is possible to achieve long-term remission in metastatic PSTT. Only a handful of previously reported cases with prolonged remission had been treated with the described combined chemotherapy and surgical approach. We suggest that this approach may be recommended for metastatic PSTT. 相似文献
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134.
Fatemeh Ghaffarifar 《Experimental parasitology》2010,126(2):126-129
Cantharidin is a natural poisonous compound secreted by male blister beetles. The effect of different doses of cantharidin on Leishmania major (MRHO/IR/75/ER) were investigated both in vitro (promastigote and amastigote viability) and in experimentally-infected BALB/c mice (skin lesions) using ointment or soluble cantharidin. In this study, cantharidin with concentrations of 0.5, 1, 2, 5, 10, 20 and 50 μg/ml inhibited the growth of L. major promastigotes after 24 h and the resultant inhibition levels were 39.22%, 41.95%, 49.88%, 54.78%, 58.01%, 68.30% and 80.04%, respectively. After 72 h, the mean number of amastigotes per macrophage in the culture using 2 μg/ml of cantharidin, (the 50% inhibitory concentration dose (IC50)), was 1.2 while in the control group it was 2.7. In order to perform the inflammatory blister technique, 500 μg of cantharidin were solved in 25 μl of DMSO to show the formation of the blister which leads to treatment of cutaneous leishmaniasis. Using the blister technique, the small lesions (<5 mm) healed after one session. Two weeks of topical treatment with 0.1% cantharidin ointment was an effective method for treating cutaneous leishmaniasis in infected BALB/c mice. 相似文献
135.
Tahereh Taheri Ali-Hatef Salmanian Fatemeh Doustdari Sima Rafati 《Experimental parasitology》2010,126(2):135-145
Leishmania major (L. major) signal peptidase type I (SPase I) is an endopeptidase encoded by a single-copy gene. In all organisms, SPase I is responsible for removing the signal peptide from secretory pre-proteins and releasing mature proteins to cellular or extra-cellular space. In this study, the role of SPase I in L. major is investigated by gene deletion using homologous recombination (HR). The null mutant of SPase I was not possible to create, suggesting that SPase I is an essential gene for parasite survival.The obtained heterozygote mutant by disrupting one allele of SPase I in L. major showed significantly reduced level of infectivity in bone marrow-derived macrophages. In addition, the heterozygote mutants are unable to cause cutaneous lesion in susceptible BALB/c mice. This is the first report showing that SPase I may have an important role in Leishmania infectivity, e.g. in differentiation and survival of amastigotes. Apparently, the SPase I expression is not essential for in vitro growth of the parasite. 相似文献
136.
Composition and antimicrobial activity of the essential oil of Dicyclophora persica Boiss. from Iran
Salehi P Sonboli A Mohammadi F 《Zeitschrift für Naturforschung. C, Journal of biosciences》2006,61(5-6):315-318
The chemical composition of the essential oil of Dicyclophora persica Boiss. was identified by GC and GC-MS analysis. The analysis of the oil resulted in the identification of forty-five components constituting 98.6% of the total oil. The main constituents were a-pinene (31.5%), (Z)-beta-ocimene (23.3%), p-cymene (6.7%) and (E)-beta-ocimene (5.4%). The antimicrobial activity of the oil was tested by the disk diffusion method against four Gram-positive (Bacillus subtilis, Staphylococcus aureus, Staphylococcus epidermidis and Enterococcus faecalis) and three Gram-negative (Escherichia coli, Klebsiella pneumoniae and Pseudomonas aeruginosa) bacteria together with a fungus (Aspergillus niger). The oil showed strong inhibition activity toward all the tested microorganisms except for Pseudomonas aeruginosa. 相似文献
137.
Grajcar L El Amri C Ghomi M Fermandjian S Huteau V Mandel R Lecomte S Baron MH 《Biopolymers》2006,82(1):6-28
We rank the reactivity of the adenyl residues (A) of model DNA and RNA molecules with electropositive subnano size [Ag]n+ sites as a function of nucleic acid primary sequences and secondary structures and in the presence of biological amounts of Cl- and Na+ or Mg2+ ions. In these conditions A is markedly more reactive than any other nucleic acid bases. A reactivity is higher in ribo (r) than in deoxyribo (d) species [pA>pdA and (pA)n>(pdA)n]. Base pairing decreases A reactivity in corresponding duplexes but much less in r than in d. In linear single and paired dCAG or dGAC loci, base stacking inhibits A reactivity even if A is bulged or mispaired (A.A). dA tracts are highly reactive only when dilution prevents self-association and duplex structures. In d hairpins the solvent-exposed A residues are reactive in CAG and GAC triloops and even more in ATC loops. Among the eight rG1N2R3A4 loops, those bearing a single A (A4) are the least reactive. The solvent-exposed A2 is reactive, but synergistic structural transitions make the initially stacked A residues of any rGNAA loop much more reactive. Mg2+ cross-bridging single strands via phosphates may screen A reactivity. In contrast d duplexes cross-bridging enables "A flipping" much more in rA.U pairs than in dA.T. Mg2+ promotes A reactivity in unpaired strands. For hairpins Mg2+ binding stabilizes the stems, but according to A position in the loops, A reactivity may be abolished, reduced, or enhanced. It is emphasized that not only accessibility but also local flexibility, concerted docking, and cation and anion binding control A reactivity. 相似文献
138.
Fatemeh Rafieenia Seyed Omar Ebrahimi Ensieh sadat Emadi Forough Taheri Somayeh Reiisi 《Biotechnology progress》2023,39(6):e3387
Today, biologic prodrugs have led to targeting specific tumor markers and have increased specificity and selectivity in cancer therapy. Various studies have shown the role of ncRNAs in cancer pathology and tumorigenesis and have suggested that ncRNAs, especially miRNAs, are valuable molecules in understanding cancer biology and therapeutic processes. Most miRNAs-based research and treatment are limited to chemically synthesized miRNAs. Synthetic alterations in these miRNA mimics may affect their folding, safety profile, and even biological activity. However, despite synthetic miRNA mimics produced by automated systems, various carriers could be used to achieve efficient production of bioengineered miRNAs through economical microbial fermentation. These bioengineered miRNAs as biological prodrugs could provide a new approach for safe therapeutic methods and drug production. In this regard, bioengineered chimeric miRNAs could be selectively processed to mature miRNAs in different types of cancer cells by targeting the desired gene and regulating cancer progression. In this article, we aim to review bioengineered miRNAs and their use in cancer therapy, as well as offering advances in this area, including the use of chimeric tRNA/pre-miRNAs. 相似文献
139.
Namvaran F Rahimi-Moghaddam P Azarpira N Nikeghbalian S 《Molecular biology reports》2012,39(3):3219-3223
Adiponectin which possesses anti-inflammatory and insulin-sensitizing properties is elevated in blood circulation of liver
cirrhosis patients. The genetic variations in the adiponectin gene can affect the circulating adiponectin level and stimulation
of adiponectin receptor that may affect the activity of adiponectin. We investigated the effect of adiponectin single nucleotide
polymorphisms (SNP) 45 T/G and adiponectin receptor-2 gene SNP 795G/A in cirrhotic Iranian population. A total of 97 cirrhotic
patients and 128 healthy controls from Iranian population were genotyped for the adiponectin and adiponectin receptor 2 gene
(+45T>G and 795G/A) by polymerase chain reaction-restriction fragment length polymorphism. G frequency was 21.1% versus 12.89%
(P = 0.001) for SNP45, and G frequency was 75.8% versus 76.2% (P = 0.526) for SNP795G/A in the patients and control group, respectively. Based on our findings, the expression of the G allele
at SNP45 is higher in the patient group compared with healthy subjects, suggesting that it may affect liver injury through
changes in the plasma adiponectin level. 相似文献
140.
Fatemeh Shaki Mir-Jamal Hosseini Mahmoud Ghazi-Khansari Jalal Pourahmad 《Biochimica et Biophysica Acta (BBA)/General Subjects》2012