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71.
BACKGROUND: Alveolar soft part sarcoma (ASPS) is a rare soft tissue tumor. It has characteristic histomorphology, with typical ultrastructural features demonstrating unique crystalloids. It occurs predominantly in adolescents and young adults, in whom the most common location is within the fascial planes of skeletal muscle of the lower extremity. CASE: We present fine needle aspiration biopsy (FNAB) findings along with histopathologic features and ultrastructural appearance of a large gluteal mass in a 29-year-old female. FNAB cytology smears showed single and small groups of polyhedral malignant cells with granular cytoplasm, anisokaryosis and prominent nucleoli. The delicate cytoplasm had a tendency to rupture, with the presence of many bare nuclei. The characteristic crystals were observed in Papanicolaou-stained smears within the cytoplasm and in the background near the tumor cells. This consolidated the radiologic suspicion of ASPS and facilitated the application of relevant ancillary tests. Biopsy of the mass showed the characteristic histologic pattern. Electron microscopy confirmed the diagnosis with demonstration of membrane-bound, rhomboid crystalloids with a latticelike ultrastructure. CONCLUSION: Detection of characteristic crystalloids in Papanicolaou-stained FNAB smears facilitated a proper evaluation and correct diagnosis of ASPS.  相似文献   
72.
BACKGROUND: The histology of a few cases of adenocarcinoma simulating cervical microglandular hyperplasia (MGH-AdCa) has been reported. However, the cytologic features of MGH-AdCa in cervical smears and the immunohistochemical profile have not been described. CASE: A 73-year-old female presented with vaginal bleeding. The cervical Pap smear was initially interpreted by the cytotechnologist as "reactive endocervical cells" and was referred for cytopathologist review. The final interpretation was atypical glandular cells of undetermined significance (AGUS), probably neoplastic. Endometrial biopsy and total abdominal hysterectomy with bilateral salpingo-oophorectomy showed International Federation of Gynecologists and Obstetricians grade 1 endometrial carcinoma. The superficial component of the tumor resembled cervical microglandular hyperplasia (MGH); the deeper component had an endometrioid pattern. The Pap smear predominantly showed a glandular component with features of MGH. However, the presence of scattered single cells with hyperchromatic nuclei, one to three nucleoli, easily detectable mitotic figures, randomly scattered apoptotic bodies and focal, watery diathesis suggested a neoplastic process. Immunohistochemistry was studied on paraffin sections. In addition to other markers, the tumor cells were immunoreactive for carcinoembryonic antigen (CEA). CONCLUSION: Although the cervical Pap smear in this case had an MGH-like pattern, some features were atypical enough to suggest a diagnosis of AGUS, probably neoplastic. CEA immunoreactivity of MGH-AdCa could also help to differentiate it from MGH.  相似文献   
73.
Ten peptides with differential growth-inhibitory activity against the gram-positive bacterium, Staphylococcus aureus, the gram-negative bacterium, Escherichia coli, and the yeast Candida albicans were isolated from an extract of the skin of a North American frog, the green frog Rana clamitans. Ranatuerin-1C (SMLSVLKNLGKVGLGLVACKINKQC), ranalexin-1Ca (FLGGLMKAFPALICAVTKKC), ranalexin-1Cb (FLGGLMKAFPAIICAVTKKC), ranatuerin-2Ca (GLFLDTLKGAAKDVAGKLLEGLKCKIAGC KP), and ranatuerin-2Cb (GLFLDTLKGLAGKLLQGLKCIKAGCKP), are members of three previously characterized families of antimicrobial peptides, first identified in the North American bullfrog Rana catesbeiana. In addition, five structurally related peptides (temporin-1Ca, -1Cb, -1Cc, -1Cd, and -1Ce), comprising 13 amino acid residues and containing a C-terminally alpha-amidated residue, belong to the temporin family first identified in the European common frog Rana temporaria. Peptides belonging to the brevinin-1, brevinin-2, esculentin-1, and esculentin-2 families, previously isolated from the skins of Asian and European Ranid frogs, were not identified in the extract. The data support the hypothesis that the distribution and amino acid sequences of the skin antimicrobial peptides are valuable tools in the identification and classification of Ranid frogs.  相似文献   
74.
Hereditary hearing loss is a genetically heterogeneous disorder. Mutations in connexin 26 (CX26), are a major cause in many countries and are largely dependent on ethnic groups. The purpose of our study was to evaluate the prevalence of GJB2 mutations among affected individuals from south of Iran. Fifty patients presenting with autosomal recessive non-syndromic hearing loss from Fars, province in south of Iran, were studied for mutations in GJB2 gene and screened by direct sequencing. Mutations were detected in 15 out of 50 patients (30?%). Eight different mutations were identified; six of them were previously identified (35delG, V27I M34V, V153I, A149T, V198M). The remaining two alleles, L28I and N169T, were novel variants. The most common mutations were 35delG followed by V153I with an allele frequency of 7 and 6?%, respectively. In this study, 30?% of our subjects were found to have the causative variants or polymorphisms in GJB2 and the c.35delG mutation was the most common cause in our patients. However, more study with larger sample size as well as in vitro functional study for these new variants in Xenopus oocytes is required.  相似文献   
75.
Aspergillus fumigatus, the main etiological agent for various forms of human aspergillosis, gets access to the respiratory system of human host by inhalation of airborne conidia. These conidia possibly adhere to extracellular matrix (ECM) proteins. Among the ECM proteins involved in adherence, fibrinogen is thought to be crucial. Here, we studied whether A. fumigatus three-week culture filtrate (3wcf) proteins promote binding of A. fumigatus to ECM proteins and promote fungal growth. We observed that incubation of ECM with 3wcf proteins led to dose- and time-dependent increase in adherence of conidia to the ECM. In order to identify the catalogue of fibrinogen-binding A. fumigatus proteins, we carried out fibrinogen affinity blotting using two-dimensional gel electrophoresed 3wcf proteins. A total of 15 fibrinogen-binding protein spots corresponding to 7 unique proteins were identified in 3wcf using matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF-TOF). Among these, 4 proteins, namely, beta-glucosidase, alpha-mannosidase, pectate lyase A and oryzin precursor were predicted to have cell wall or extracellular localization, whereas amidase family protein and two hypothetical proteins did not display the signal sequence. This study reports seven novel fibrinogen-binding proteins of A. fumigatus, some of which could be further explored for targeting the adhesion phenomenon as antifungal strategy.  相似文献   
76.
77.

Background  

Cloning of cattle by somatic cell nuclear transfer (SCNT) is associated with a high incidence of pregnancy failure characterized by abnormal placental and foetal development. These abnormalities are thought to be due, in part, to incomplete re-setting of the epigenetic state of DNA in the donor somatic cell nucleus to a state that is capable of driving embryonic and foetal development to completion. Here, we tested the hypothesis that DNA methylation patterns were not appropriately established during nuclear reprogramming following SCNT. A panel of imprinted, non-imprinted genes and satellite repeat sequences was examined in tissues collected from viable and failing mid-gestation SCNT foetuses and compared with similar tissues from gestation-matched normal foetuses generated by artificial insemination (AI).  相似文献   
78.
Keyhole limpet hemocyanin (KLH) is widely used as an immune stimulant and hapten carrier derived from a marine mollusc Megathura crenulata. To provide details of the stability and equilibrium of KLH, different intermediate species were investigated with a series of biophysical techniques: circular dichroism, binding of hydrophobic dye, 1-anilino-8-naphthalene sulfonic acid, acrylamide-induced fluorescence quenching, thermal stability and dynamic light scattering. KLH in its native state at pH 7.4 exists in the stable didecameric form with hydrodynamic radii (R h) of 28.22 nm, which is approximately equal to a molecular mass of 8.8 ± 0.6 MDa. The experimental results demonstrated the presence of two structurally distinct species in the conformational transition of KLH under acidic conditions. One species populates at pH 2.8, characterized as decameric (4.8 ± 0.2 MDa; R h = 22.02 nm), molten globule-like state, while the other accumulates at pH 1.2 and is characterized as a tetramer (2.4 ± 0.8 MDa; R h = 16.47 nm) with more organized secondary and tertiary structures. Our experimental manipulation of the oligomeric states of KLH has provided data that correlate well with the known oligomeric forms obtained from total KLH formed in vivo and extends our understanding of multimer formation by KLH. The results are of particular interest in light of the important role of the mechanistic pathway of pH-dependent structural changes of Hc stability in the biochemical and medical applications of these respiratory proteins.  相似文献   
79.
Two hundred and ninety three fully identified species representing 203 genera and 77 families were collected from Mt. Merapi, Mt. Sago, Baso, Simarasap Forest, Ngalau Forest, Padang, Air Sirah Forest, and Ulu Gadat Forest in West Sumatra and tested for the presence of alkaloids. Positive results were obtained for 58 species representing 50 genera and 26 families.  相似文献   
80.
Exposure to lead is known to cause vasoconstriction, exact mechanism of which remains to be elucidated. In this study, we investigate contractile responses of rat aortal rings equilibrated with Pb(II) in organ bath system, explore pathways responsible for hypercontraction and examine two ameliorators of lead-induced hypercontraction. At 1 μmol L?1 Pb(II), aortal rings showed an average increase of 50 % in isometric contraction. Incubation of rings, unexposed to Pb(II), with 1 μmol L?1 sodium nitroprusside (nitric oxide (NO) donor), 100 μmol L?1 apocynin (reactive oxygen species (ROS) inhibitor), and 100 μmol L?1 indomethacin (cyclooxygenase inhibitor) lead to decrease in phenylephrine-induced contraction by 31, 27, and 29 %, respectively. This decrease of contraction for Pb(II)-exposed rings was 48, 53, and 38 %, respectively, indicating that ROS- and NO-dependent components of contractions are significantly elevated in Pb(II)-induced hypercontraction. Cyclooxygenase-dependent contractile component did not show significant elevation. Eugenol and carvacrol are plant-derived phenols known to possess antioxidant activity and hence could act as possible ameliorators of hypercontraction. At saturating concentrations of 100 μmol L?1, eugenol and carvacrol caused a decrease in contraction by 38 and 42 % in unexposed rings and 46 and 50 % in Pb(II)-exposed rings. Co-incubation of rings with eugenol/carvacrol and various inhibitors suggests that both these active principles exert their relaxant effect via quenching of ROS and stimulation of NO synthesis. To conclude, Pb(II) is shown to induce hypercontraction of aortal rings through elevation of ROS and depletion of NO. This hypercontraction is effectively mitigated by eugenol and carvacrol.  相似文献   
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