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101.
Marwan Osman Dima El Safadi Sadia Benamrouz Karine Guyot Eduardo Dei-Cas El Moukhtar Aliouat Colette Creusy Hassan Mallat Monzer Hamze Fouad Dabboussi Eric Viscogliosi Gabriela Certad 《PloS one》2015,10(5)
Cryptosporidium spp. represent a major public health problem worldwide and infect the gastrointestinal tract of both immunocompetent and immunocompromised persons. The prevalence of these parasites varies by geographic region, and no data are currently available in Lebanon. To promote an understanding of the epidemiology of cryptosporidiosisin this country, the main aim of this study was to determine the prevalence Cryptosporidium in symptomatic hospitalized patients, and to analyze the genetic diversity of the corresponding isolates. Fecal specimens were collected in four hospitals in North Lebanon from 163 patients (77 males and 86 females, ranging in age from 1 to 88 years, with a mean age of 22 years) presenting gastrointestinal disorders during the period July to December 2013. The overall prevalence of Cryptosporidium spp. infection obtained by modified Ziehl-Neelsen staining and/or nested PCR was 11%, and children <5 years old showed a higher rate of Cryptosporidium spp. The PCR products of the 15 positive samples were successfully sequenced. Among them, 10 isolates (66.7%) were identified as C. hominis, while the remaining 5 (33.3%) were identified as C. parvum. After analysis of the gp60 locus, C. hominis IdA19, a rare subtype, was found to be predominant. Two C. parvum subtypes were found: IIaA15G1R1 and IIaA15G2R1. The molecular characterization of Cryptosporidium isolates is an important step in improving our understanding of the epidemiology and transmission of the infection. 相似文献
102.
Osamu Kaneko Lucy Gong Jingli Zhang Johanna K. Hansen Raffit Hassan Byungkook Lee Mitchell Ho 《The Journal of biological chemistry》2009,284(6):3739-3749
Ovarian cancer and malignant mesothelioma frequently express both
mesothelin and CA125 (also known as MUC16) at high levels on the cell surface.
The interaction between mesothelin and CA125 may facilitate the implantation
and peritoneal spread of tumors by cell adhesion, whereas the detailed nature
of this interaction is still unknown. Here, we used truncated mutagenesis and
alanine replacement techniques to identify a binding site on mesothelin for
CA125. We examined the molecular interaction by Western blot overlay assays
and further quantitatively analyzed by enzyme-linked immunosorbent assay. We
also evaluated the binding on cancer cells by flow cytometry. We identified
the region (296–359) consisting of 64 amino acids at the N-terminal of
cell surface mesothelin as the minimum fragment for complete binding activity
to CA125. We found that substitution of tyrosine 318 with an alanine abolished
CA125 binding. Replacement of tryptophan 321 and glutamic acid 324 with
alanine could partially decrease binding to CA125, whereas mutation of
histidine 354 had no effect. These results indicate that a
conformation-sensitive structure of the region (296–359) is required and
sufficient for the binding of mesothelin to CA125. In addition, we have shown
that a single chain monoclonal antibody (SS1) recognizes this CA125-binding
domain and blocks the mesothelin-CA125 interaction on cancer cells. The
identified CA125-binding domain significantly inhibits cancer cell adhesion
and merits evaluation as a new therapeutic agent for preventing or treating
peritoneal malignant tumors.Ovarian cancer largely is confined to the peritoneal cavity for much of its
natural history (1). Peritoneal
mesothelioma is a highly invasive tumor originating from the mesothelial
linings of the peritoneum (2).
The development of effective drug regimens against ovarian cancer and
mesothelioma has proven extremely difficult.Mesothelin was first identified in 1992 by the monoclonal antibody
(mAb)2 K1 that was
generated by the immunization of mice with human ovarian carcinoma (OVCAR-3)
cells (3). The mesothelin gene
encodes a 71-kDa precursor protein that is processed to a 40-kDa protein
termed mesothelin, which is a glycosylphosphatidylinositol (GPI)-anchored
glycoprotein present on the cell surface
(4). Mesothelin is a
differentiation antigen that is present on a restricted set of normal adult
tissues such as the mesothelium. In contrast, it is overexpressed in a variety
of cancers including mesothelioma, ovarian cancer, and pancreatic cancer
(5). In addition, mesothelin is
also expressed on the surface of non-small cell lung cancer cells
(6,
7), especially most lung
adenocarcinomas (8).We and others have shown that mesothelin is shed from tumor cells
(9,
10), and antibodies specific
for mesothelin are elevated in the sera of patients with mesothelioma and
ovarian cancer (11). Shed
serum mesothelin has been approved by the United States Food and Drug
Administration (FDA) as a new diagnostic biomarker in mesothelioma. In a Phase
I clinical study of an intrapleural interferon-β gene transfer using an
adenoviral vector in patients with mesotheliomas, we found that antitumor
immune responses targeting mesothelin were elicited in several patients
(12). A recent study indicated
that anti-mesothelin antibodies and circulating mesothelin relate to the
clinical state in ovarian cancer patients
(13). Pastan and colleagues
(14) developed an immunotoxin
(SS1P) with a Fv for mesothelin. Two Phase I clinical trials were completed at
the National Cancer Institute (National Institutes of Health, Bethesda, MD)
and there was sufficient antitumor activity of SS1P to justify a Phase II
trial. A chimeric antibody containing the mouse SS1 Fv for mesothelin was also
developed and is currently examined in a Phase I clinical trial for ovarian
cancer, mesothelioma, pancreatic cancer, and non-small cell lung cancer
(15).Mucins are heavily glycosylated proteins found in the mucus layer or at the
cell surface of many epitheliums
(16). There are two
structurally distinct families of mucins, secreted and membrane-bound forms.
CA125 (also known as MUC16) was first identified in 1981 by OC125, a mAb that
had been developed from mice immunized with human ovarian cancer cells
(17). The first cDNA clones
were reported in 2001 (18,
19). CA125 is a very large
membrane-bound cell surface mucin, with an average molecular mass between 2.5
and 5 million daltons. It is also heavily glycosylated with both
O-linked and N-linked oligosaccharides
(20). The peptide backbone of
CA125 is composed of the N-terminal region, extensive Ser/Thr/Pro-rich tandem
repeats (TR) with 156 amino acids each with both N- and
O-glycosylations, a SEA domain with high levels of
O-glycosylation and a C-terminal region with a short cytoplasmic tail
(19). The SEA domain was first
identified as a module commonly found in sea urchin sperm protein,
enterokinase and agrin (21,
22). The significance of the
SEA domain in CA125 is not clear.CA125 was originally used as a biomarker in ovarian cancer due to its high
expression in ovarian carcinomas and that it is shed into the serum
(23). A majority (88%) of
mesotheliomas are also CA125 positive on the cell membrane
(24). It was shown that 25% of
peritoneal mesotheliomas have high CA125 expression
(25). The intensity of CA125
membranous expression is indistinguishable between ovarian carcinomas and
peritoneal mesotheliomas. Gene expression analysis using the SAGE tag data
base has shown that mesothelioma has the second highest co-expression of CA125
and mesothelin after ovarian cancer
(26). Rump and colleagues
(26) have shown that
mesothelin binds to CA125 and that this interaction may mediate cell adhesion.
Scholler et al. (27)
recently showed that CA125/mesothelin-dependent cell attachment could be
blocked with anti-CA125 antibodies. Because mesothelin is present on
peritoneal mesothelium, there may be an important role for the
mesothelin-CA125 interaction in the tumorigenesis of ovarian cancer and
mesothelioma in the peritoneal cavity. The mesothelin binding site on CA125
may lie within the 156-amino acid TR units, indicating multimeric binding of
mesothelin to CA125. It has been found that the extraordinarily abundant
N-glycans on CA125, presumably in the TR region, are required for
binding to both glycosylated and non-glycosylated mesothelin
(28).Here, we identified the binding site of CA125 on mesothelin by use of
truncated mutagenesis and alanine replacement approaches. We measured binding
qualitatively by Western blot overlay assays and quantitatively by
enzyme-linked immunosorbent assay (ELISA). We also evaluated the interaction
of CA125 and mesothelin on cancer cells by flow cytometry. Furthermore, we
have shown that a single chain mAb (SS1) recognized the CA125-binding domain
and blocked the mesothelin-CA125 interaction on cancer cells. The identified
CA125-binding domain-Fc fusion protein also significantly inhibited cancer
cell adhesion. Our results suggest that conformation-sensitive structures of
the region (296–359) are required and sufficient for specific binding of
mesothelin to CA125. The domain proteins or the antibodies that block the
mesothelin-CA125 interaction merit evaluation as new therapeutic agents in
treating peritoneal malignant tumors. 相似文献
103.
Syed Mohammed Basheeruddin Asdaq Naira Nayeem Abida Md. Tauquir Alam Saleh I. Alaqel Mohd. Imran El-Waleed Elamin Hassan Syed Imam Rabbani 《Saudi Journal of Biological Sciences》2022,29(3):1456-1464
Tectona grandis L.f is a timber plant that is commonly referred to as teak. Its wide use as a medicine in the various indigenous systems makes it a plant of importance. A wide gamut of phytoconstituents like alkaloids, phenolic glycosides, steroids, etc. has been reported. A renewed interest in this plant has resulted in scientific investigations by various researchers towards the isolation and identification of active constituents along with scientific proof of its biological activities. The different parts of the plant have been scientifically evaluated for their antioxidant, antipyretic, analgesic, hypoglycemic, wound healing, cytotoxic, and many more biological activities. Documentation of this scientific knowledge is of importance to have consolidated precise information encompassing the various aspects of this plant, which could provide a base for future studies. This review is a compilation of the salient reports on these investigations concerning phytochemistry, the methods used to identify and quantify the constituents, the evaluation methods of the biological activity, toxicological studies, allergies and the patent/patent applications. This will further help researchers to find an area of the gap for future studies. 相似文献
104.
Devina Lobine Bryan Pairyanen Gokhan Zengin Mustafa Abdullah Yılmaz Rayene Ouelbani Souheir Bensari Gunes Ak Hassan H. Abdallah Muhammad Imran Mohamad Fawzi Mahomoodally 《化学与生物多样性》2021,18(4):e2000999
Toddalia asiatica (L.) Lam. is extensively used in traditional medicinal systems by various cultures. Despite its frequent use in traditional medicine, there is still a paucity of scientific information on T. asiatica growing on the tropical island of Mauritius. Therefore, the present study was designed to appraise the pharmacological and phytochemical profile of extracts (methanol, ethyl acetate and water) and essential oil obtained from aerial parts of T. asiatica. Biological investigation involved the evaluation of in vitro antioxidant and enzyme inhibitory potentials. The chemical profile of the EO was determined using gas chromatography coupled to mass spectrometry (GC/MS) analysis, while for the extracts, the total phenolic (TPC) and flavonoid content were quantified as well as their individual phenolic compounds by LC/MS/MS. Quinic acid, fumaric acid, chlorogenic acid, quercitrin and isoquercitrin were the main compounds in the extracts. Highest total phenolic (82.5±0.94 mg gallic acid equivalent (GAE/g)) and flavonoid (43.8±0.31 mg rutin equivalent (RE/g)) content were observed for the methanol extract. The GC/MS analysis has shown the presence of 26 compounds with linalool (30.9 %), linalyl acetate (20.9 %) and β-phellandrene (7.9 %) being most abundant components in the EO. The extracts and EO showed notable antioxidant properties, with the methanol extract proved to be superior source of antioxidant compounds. Noteworthy anti-acetylcholinesterase (AChE) and anti-butyrylcholinesterase (BChE) effects were recorded for the tested samples, while only the methanol and ethyl acetate extracts were active against tyrosinase. With respect to antidiabetic effects, the extracts and EO were potent inhibitors of α-glucosidase, while modest activity was recorded against α-amylase. Docking results showed that linalyl acetate has the highest affinity to interact with the active site of BChE with docking score of −6.25 kcal/mol. The findings amassed herein act as a stimulus for further investigations of this plant as a potential source of bioactive compounds which can be exploited as phyto-therapeutics. 相似文献
105.
Aklima Nasrin Mahbub Hassan Ping Ye 《Biochemical and biophysical research communications》2018,495(3):2118-2124
How to effectively delivering therapeutic agents, including γ-secretase inhibitors (GSIs), into live cells, remains a significant challenge. This study assessed the effect of Notch signaling inhibition by examining levels of the Notch1 intracellular domain (N1ICD) in cultured oral cancer cells analyzed with random stitched images (2D) and 3D visualizations using confocal microscopy and quantitative gene analysis. Substantially, we have developed a novel method to assist the delivery of γ-secretase inhibitor, DAPT, into live cells in the presence of an effective minimum concentration of Triton-X100 (0.001%) without damaging cell activity and membrane integrity assessed with cell proliferation assays. The images obtained in this study showed that DAPT alone could not block the γ-secretase inhibitor despite inhibiting cell growth. Further analysis of quantitative gene expressions of Notch signaling canonical pathway to verify the effectiveness of the novel method for delivering inhibitor into live cells, displayed deregulation of Notch1, Delta-like ligand 1 (DLL1) and hairy and enhancer of split 1 (Hes1). Our data suggest that Notch1/Hes1 signaling pathway is deactivated using DAPT with a low dose of Triton-X100 in this cancer cells. And the finding also suggests that Notch1 could be engaged by DLL1 to promote differentiation in oral cancer cells. Using this approach, we demonstrate that Triton-X100 is a promising and effective permeabilization agent to deliver γ-secretase inhibitor DAPT into live oral epithelial cells. This strategy has the potential to implicate in the treatment of cancer diseases. 相似文献
106.
Hassan Ashktorab Hamed Rahi Daniel Wansley Sudhir Varma Babak Shokrani Edward Lee Mohammad Daremipouran Adeyinka Laiyemo Ajay Goel John M Carethers Hassan Brim 《Epigenetics》2013,8(8):807-815
CpG Island Methylator Phenotype (CIMP) is one of the underlying mechanisms in colorectal cancer (CRC). This study aimed to define a methylome signature in CRC through a methylation microarray analysis and a compilation of promising CIMP markers from the literature. Illumina HumanMethylation27 (IHM27) array data was generated and analyzed based on statistical differences in methylation data (1st approach) or based on overall differences in methylation percentages using lower 95% CI (2nd approach). Pyrosequencing was performed for the validation of nine genes. A meta-analysis was used to identify CIMP and non-CIMP markers that were hypermethylated in CRC but did not yet make it to the CIMP genes’ list. Our 1st approach for array data analysis demonstrated the limitations in selecting genes for further validation, highlighting the need for the 2nd bioinformatics approach to adequately select genes with differential aberrant methylation. A more comprehensive list, which included non-CIMP genes, such as APC, EVL, CD109, PTEN, TWIST1, DCC, PTPRD, SFRP1, ICAM5, RASSF1A, EYA4, 30ST2, LAMA1, KCNQ5, ADHEF1, and TFPI2, was established. Array data are useful to categorize and cluster colonic lesions based on their global methylation profiles; however, its usefulness in identifying robust methylation markers is limited and rely on the data analysis method. We have identified 16 non-CIMP-panel genes for which we provide rationale for inclusion in a more comprehensive characterization of CIMP+ CRCs. The identification of a definitive list for methylome specific genes in CRC will contribute to better clinical management of CRC patients. 相似文献
107.
Faraag Ahmed Hassan Ibrahim Shafaa Medhat W. Elkholy Nourhan S. AbdelHafez Lina Jamil M. 《International microbiology》2022,25(3):663-663
International Microbiology - 相似文献
108.
Biller M Mårdberg K Hassan H Clausen H Bolmstedt A Bergström T Olofsson S 《Glycobiology》2000,10(12):1259-1269
The pathogenesis of herpes simplex virus type 1 (HSV-1) implies the sequential infection of many cell types from mucosal cells to neurons, each having a unique pattern of protein glycosylation. The HSV-1 glycoprotein gC-1 is highly glycosylated and contains not only N-linked glycans but also a large number of O-linked glycans, some of which are clustered into two pronase-resistant arrays in the vicinity of the HSV-1 receptor-binding domain of gC-1. The aim of the present study was to characterize gC-1 signals for addition of clustered glycans, to determine the efficacy of synthetic peptides, representing putative O-glycosylation signals, as substrates for a panel of GalNAc transferases, and to identify possible effects of early O-linked glycosylation on the biological functions of gC-1. Gel filtration analysis of the pronase-resistant gC-1 O-glycan clusters from a glycoprotein mutant, lacking a site for N-linked glycosylation at Asn 73 in the vicinity of the O-glycosylation signal, suggested that one function of this N-linked glycan was to modulate the access for GalNAc transferases to one particular O-glycosylation peptide signal (aa 80-104). The ability of four GalNAc-transferase isoenzymes with different cell type expression patterns to initialize O-glycosylation of synthetic gC-1 derived peptides was analyzed. Two synthetic gC-1 peptides (aa 55-69 and aa 80-104) were excellent substrates for all four GalNAc-transferases, suggesting that cell types expressing less frequent GalNAc transferase species with unusual acceptor peptide sequence specificities may also produce a highly O-glycosylated gC-1 after HSV-1 infection. The O-linked glycans were not essential for cell surface expression of gC-1, but monoclonal antibody-assisted epitope analysis of N-acetylgalactosaminidase-treated gC-1 showed that the O-linked monosaccharide GalNAc contributed to expression of a three-dimensional epitope overlapping the heparan sulfate-binding domain of gC-1. 相似文献
109.
M C Garel W Hassan M T Coquelet M Goossens J Rosa N Arous 《Biochimica et biophysica acta》1976,420(1):97-104
The present report describes clinical, hematological and biochemical studies of a 27-year old Egyptian woman in whom a fast moving Hb variant was found. The abnormal Hb constituted 48% of the total erythrocyte Hb of the propositus and her father. Structural studies demonstrated that in the abnormal Hb lysine beta 65 is replaced by glutamine. The new Hb mutant is designated hemoglobin J Cairo beta 65 (E9) Lys leads to Gln. This substitution results in only a moderate decrease in cooperativity. No evidence of Hb instability was found. A slight anemic state has been observed in the propositus since she reached adolescence. 相似文献
110.
Zusammenfassung Kernpolyeder vonMamestra brassicae (L.) wurden auf Nebenwirkungen an zwei Entomophagen-Arten in der Basis- Konzentration (LC100 für den natürlichen Wirt) sowie der 5- und 10 fachen Konzentration geprüft. Schadwirkung durch Kontakt mit frisch angetrocknetem
Belag bzw. durch Verfüttern eines kontaminierten N?hrsubstrates auf den EiparasitenTrichogramma cacoeciae
Marchal konnte nicht nachgewiesen werden. Ebenso wurde die Entwicklung vonT. cacoeciae in parasitierten Wirtseiern durch eine Tauchbehandlung mit der Kernpolyeder-Suspension in verschiedenen Intervallen nach
der Parasitierung nicht gest?rt. Im Wahl- und Nichtwahlversuch konnte keine Repellentwirkung von Wirtseiern festgstellt werden,
die in eine Kernpolyeder-Suspension getaucht worden waren.
Die r?uberischen Larven vonChrysopa carnea
Steph. waren gegenüber der 10fachen Basiskonzentration bei direktem Bespritzen der Larven, Kontakt mit einem frisch angetrockneten
sprit zbelag sowie bei peroraler Aufnahme unempfindlich, wie die Frassleistung der Larven, die Fekundit?t der Imagines sowie
die Schlüpfrate der Eier zeigte. Bei praktischen Eins?tzen von Kernpolyeder-Pr?paraten zur Bek?mpfung der Kohleule sind im
Gegensatz zu den üblichen Anwendungen von Phosphors?ureestern keine direkten Nebenwirkungen auf die untersuchten Nutzinsekten
zu erwarten.
Nr. 2 der Serie: Wirkung von Insektenpathogenen auf Entomophagen. Als Nr. 1 gilt:S. Hassan & A. Krieg: über die schonende Wirkung vonBacillus thuringiensis-Pr?paraten auf den ParasitenTrichogramma cacoeciae (Hym.: Trichogrammatidae). — Z. Pfl. Krankh. Pfl. Schutz, 82, 515–521, 1975. 相似文献
Summary The side effect of a water suspension of polyhedral inclusion bodies of nuclnear polyhedrosis virus (NPV) fromMamestra brassicae (L.) in a concentration of 1-, 5-, and 10-fold of the LC100 for the natural host was tested on two beneficial insects. No reduction in the parasitization capacity ofTrichogramma cacoeciae Marchal (Hym.: Trichogrammatidae) was recorded when adults were exposed to a fresh dry film, or fed on contaminated honey-agar. The development of the parasite inSitotroga cerealella Oliv. host eggs was not affected when these were dipped in a suspension of the NPV at different time intervals after parasitization. In additional tests, it was shown that deposit of the NPV suspension had no repellent effect onTrichogramma. The feeding capacity of the predatory larve ofChrysopa carnea Steph., fecundity of the adults as well as viability of the eggs were not affected when the larvae were directly sprayed with the highest tested concentration of the suspension, exposed to fresh dry film or fed on contaminated diet. These experiments indicate that, in contrast to the use of the conventional organophosphorus insecticides, no hazard to the tested beneficial insects should be expected when the preparation of the polyhedral inclusion bodies will be used in the field.
Nr. 2 der Serie: Wirkung von Insektenpathogenen auf Entomophagen. Als Nr. 1 gilt:S. Hassan & A. Krieg: über die schonende Wirkung vonBacillus thuringiensis-Pr?paraten auf den ParasitenTrichogramma cacoeciae (Hym.: Trichogrammatidae). — Z. Pfl. Krankh. Pfl. Schutz, 82, 515–521, 1975. 相似文献