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71.
Multiple genetic typing of Salmonella enterica serotype typhimurium isolates of different phage types (DT104, U302, DT204b,and DT49) from animals and humans in England,Wales, and Northern Ireland
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Liebana E Garcia-Migura L Clouting C Clifton-Hadley FA Lindsay E Threlfall EJ McDowell SW Davies RH 《Journal of clinical microbiology》2002,40(12):4450-4456
Salmonella enterica serotype Typhimurium is a common cause of salmonellosis among humans and animals in England, Wales, and Northern Ireland. Phage types DT104 and U302 were the most prevalent types in both livestock and humans in 2001. In addition, Salmonella serotype Typhimurium DT204b was responsible for a recent international outbreak involving England. A total of 119 isolates from humans (n = 28) and animals or their environment (n = 91), belonging to DT104 (n = 66), U302 (n = 33), DT204b (n = 12), and DT49 (n = 8), were fingerprinted by a combination of well-established genetic methods (pulsed-field gel electrophoresis [PFGE], PstI/SphI [PS] ribotyping, and plasmid profiling). The different techniques identified different degrees of polymorphism (from greatest to least, plasmid profiling [40 types], PS ribotyping [34 types], and PFGE [23 types]). It seems clear that a prevalent genomic clone, as well as a variety of less frequent clones, is present for each of the phage types. In most cases, the prevalent clones appeared within isolates from several animal species and from several geographical locations. We did not find clear evidence of a higher degree of diversity for any of the animal species included, or of any link between isolates from particular animal species and humans. The data presented show the inaccuracy of drawing epidemiological conclusions based on a single fingerprinting method. Strains that share one of the markers do not necessarily belong to the same clone, and a multiple typing approach is required to enable enough discrimination to track strains for epidemiological investigations. 相似文献
72.
Elisabeth Puchhammer-Stckl Wolfgang Mor Michael Kundi Franz-Xaver Heinz Hanns Hofmann Christian Kunz 《Journal of medical virology》1994,43(2):143-147
Serum samples from 46 children with chronic and probably transfusion acquired hepatitis were tested for the presence of hepatitis C virus (HCV) RNA by a “nested” polymerase chain reaction (PCR) assay, to judge a possible risk of HCV transmission from these patients. In 73% of the samples, viral RNA was detected, indicating a high virus prevalence in this patient group. High titers of HCV-RNA were observed in some sera as shown by the detection of virus in some samples even at dilutions of 10?3. Comparison of simultaneously obtained PCR results and ALT values revealed no significant correlation between virus presence in serum and higher ALT levels. It was, however, shown that unusually high ALT values may reflect a high titer of viral RNA in serum. To investigate the prevalence of viral RNA in saliva, which could be a vehicle of virus transmission, 35 throat washing samples from the HCV-infected children were screened by PCR. Using three different sample preparation procedures, 20% of the throat washings were found to be positive for HCV-RNA. This indicates a prevalence of virus in this fluid lower than that reported previously. © 1994 Wiley-Liss, Inc. 相似文献
73.
Frank EL Schwarz EL Juenke J Annesley TM Roberts WL 《American journal of clinical pathology》2002,118(1):124-131
Carbamazepine, phenobarbital, phenytoin, and valproic acid are commonly used antiepileptic drugs that show complicated pharmacokinetic behavior Nonisotopic immunoassays are used routinely to monitor these drugs, and assay specificity is important to obtain accurate results. By using samples from subjects receiving each of these antiepileptic medications, competitive immunoassays for them were evaluated on an IMMULITE 2000 automated chemiluminescent analyzer (Diagnostic Products, Los Angeles, CA). Phenytoin assays were evaluated using an additional set of samples from patients with abnormal renal function. All 4 methods were linear, had imprecision of less than 10%, and compared well with other commercial immunoassays. A positive bias was observed for phenytoin measured in samples from uremic patients compared with a high-performance liquid chromatography reference method. The molar cross-reactivity of carbamazepine-10,11-epoxide was 12% in the carbamazepine assay. Phenytoin metabolites and fosphenytoin had substantial cross-reactivity in the phenytoin assay. All antiepileptic drug assays performed well and are suitable for use in monitoring patients receiving antiepileptic drug therapy. One possible exception is the phenytoin assay with samples from patients with renal insufficiency. 相似文献
74.
Vincent Thomas-de-Montpréville Rémi Nottin Elisabeth Dulmet Alain Serraf 《Cardiovascular pathology》2007,16(1):22-28
BACKGROUND: Heart tumors are rare lesions with variegated histological types. Their clinicopathological features could be more comprehensively categorized. METHODS: This is a 19-year retrospective study of 17 infants/toddlers (<2 years of age) and 42 patients aged between 14 and 79 years (mean = 51.5) in a surgical center. RESULTS: Congenital tumors (n = 17; 29%), including rhabdomyomas (n = 9), ventricular fibromas (n = 6), and hemangiomas (n = 1), required surgery mainly because of mass effect. Familial myofibromatosis was the only embolic congenital lesion. Acquired benign tumors (n = 28; 47%) included myxomas (n = 21), fibroelastomas (n = 3), myofibroblastic inflammatory tumors (n = 2), and lipomas (n = 2). Eight (29%) were revealed by systemic embolization. These benign noncongenital tumors were all treated by complete resection, except for an incompletely resected lipoma of the mitral valve. Postoperative arrhythmia (n = 1) and pericardial effusion (n = 3) were the only complications. Primary sarcomas (n = 8; 14%) were mostly vascular tumors (five of eight), and patients with high-grade tumors had a mean survival of 15 months (n = 5). Cardiac metastases (n = 6; 10%) were from carcinomas (n = 3) or sarcomas (n = 3); apart from a necrotic metastasis, all patients died (mean survival of 6 months). CONCLUSIONS: This study shows that, regardless of patients' age, heart tumors can be classified as: (a) congenital lesions, which are spontaneously nonprogressive or regressive lesions possibly requiring surgery mainly because of mass effect; (b) acquired benign tumors, which are lesions requiring surgery often because of embolization risk; and (c) primary and secondary malignant tumors, which are lesions with globally poor prognosis but with some indications for resection. 相似文献
75.
76.
Rammelt S Schulze E Witt M Petsch E Biewener A Pompe W Zwipp H 《Cells, tissues, organs》2004,178(3):146-157
The early interface reaction of cancellous bone to a nanocrystalline hydroxyapatite (HA) cement containing 3 wt% collagen type I (HA/Coll) with a setting under physiological temperature and pH was observed using immunohistochemical techniques. Pure HA served as a control. Cylinders with a diameter of 2 mm were implanted into the proximal tibia of 72 adult Wistar rats. Histological sections of 6 animals were prepared after 1, 2, 4, 6, 14 and 28 days. First, osteoblast-like cells as well as a marked reaction for osteonectin, osteopontin and its ligand CD44 were observed as early as 2 days after implantation at the interface around HA/Coll implants. Further, reactivity for ED1 and cathepsin D, both markers for phagocytotic cells, appeared earlier and stronger around HA/Coll. In cell counts, a significantly higher average number of ED1- and cathepsin D-positive phagocytotic cells was observed around the HA/Coll implants on days 6 (p < 0.01), 14 and 28 (p < 0.05). The number of osteopontin-positive cells was significantly higher around HA/Coll implants at days 6 and 14 (p < 0.05). Two weeks after the implantation, first islands of newly formed woven bone were observed around the HA/Coll implant, but not around the control implant. The amount of direct bone contact after 28 days averaged 28% around pure HA and 51% around HA/Coll implants (p < 0.05). While both implants displayed a good osteoconductivity, a higher bone remodelling activity was observed around collagen-containing HA implants compared to pure HA implants. It appears that the addition of collagen to HA implants can enhance both phagocytotic and osteogenic processes. This may result in an earlier acceptance and better osseointegration of the HA/Coll implants into the surrounding tissue. 相似文献
77.
Peter J Brasted Timothy J Bussey Elisabeth A Murray Steven P Wise 《Journal of neurophysiology》2002,87(1):631-633
Rhesus monkeys learned a series of conditional visuomotor associations involving two-dimensional "objects" that instructed one of three responses: tapping a touch screen, steady contact with the screen for a brief period, or steady contact for a longer period. Relative to controls, fornix-transected monkeys were impaired in the acquisition of new associations and in the retention of preoperatively learned ones. These findings challenge the view that the hippocampal system participates in associative learning only when spatial information is relevant to either the stimulus or the response. 相似文献
78.
Doris Škorić‐Milosavljević Fleur V. Y. Tjong Julien Barc Ad P. C. M. Backx Sally‐Ann B. Clur Karin van Spaendonck‐Zwarts Roelof‐Jan Oostra Najim Lahrouchi Leander Beekman Regina Bökenkamp Daniela Q. C. M. Barge‐Schaapveld Barbara J. Mulder Elisabeth M. Lodder Connie R. Bezzina Alex V. Postma 《American journal of medical genetics. Part A》2019,179(9):1836-1845
The first human mutations in GATA6 were described in a cohort of patients with persistent truncus arteriosus, and the phenotypic spectrum has expanded since then. This study underscores the broad phenotypic spectrum by presenting two patients with de novo GATA6 mutations, both exhibiting complex cardiac defects, pancreatic, and other abnormalities. Furthermore, we provided a detailed overview of all published human genetic variation in/near GATA6 published to date and the associated phenotypes (n = 78). We conclude that the most common phenotypes associated with a mutation in GATA6 were structural cardiac and pancreatic abnormalities, with a penetrance of 87 and 60%, respectively. Other common malformations were gallbladder agenesis, congenital diaphragmatic hernia, and neurocognitive abnormalities, mostly developmental delay. Fifty‐eight percent of the mutations were de novo, and these patients more often had an anomaly of intracardiac connections, an anomaly of the great arteries, and hypothyroidism, compared with those with inherited mutations. Functional studies mostly support loss‐of‐function as the pathophysiological mechanism. In conclusion, GATA6 mutations give a wide range of phenotypic defects, most frequently malformations of the heart and pancreas. This highlights the importance of detailed clinical evaluation of identified carriers to evaluate their full phenotypic spectrum. 相似文献
79.
S C Bell R F James J A Jackson S R Patel G T Waites K Walczak 《American journal of reproductive immunology (New York, N.Y. : 1989)》1989,20(3):87-96
Monoclonal antibodies were raised against pregnancy-associated endometrial alpha 1-globulin (alpha 1-PEG), a 32 KD insulin-like growth factor binding protein (IGF-BP), which represents a major secretory product of the human decidualized endometrium during pregnancy. This class of IGF-BP has been implicated in the modulation of action, inhibitory and stimulatory, of insulin-like growth factors. Immunization with the protein purified from pregnancy endometrium resulted after myeloma fusion in the isolation of six hybridoma clones and the antibodies produced were characterized. The Ka of the antibodies ranged between 4.75 x 10(9) M-1 and 0.7 x 10(8) M-1. In Western blots all monoclonal antibodies reacted with purified protein of molecular weight 32 KD and specifically detected this IGF-BP species in culture medium and cytosolic extracts of pregnancy endometrium and amniotic fluid. The monoclonal antibodies appear to define three epitope-bearing regions as evidenced by their reactivity to polypeptide fragments of the protein. After synthesis and secretion by tissue explants in vitro the protein is susceptible to cleavage into fragments possessing different monoclonal antibody-defined reactivity. Employing immunohistochemical techniques the protein was principally localized to decidual cells in tissue sections of pregnancy endometrium and solely to these cells after enzymic digestion of the tissue. The implications of these results are discussed with respect to potential role of IGF-BP in the action of IGF upon the IGF-1 receptor-bearing populations, including lymphocytes and trophoblast cells, D in the decidua. 相似文献
80.
Claus J. M?ller Anne Grete Byskov Jürgen Roth Julio E. Celis Elisabeth Bock 《Anatomy and embryology》1991,184(6):541-548
Summary The expression of theNeuralCell AdhesionMolecule, NCAM, in mouse gonads and ducts was studied from fetal life to maturity. The methods used were immunocytochemical staining and Western blotting. The immunocytochemical studies showed that the only structures that remain NCAM-positive throughout life were the mesonephric-derived rete ovarii and rete testis. Also in the fetal gonads some somatic cell lining the groups of differentiating germ cells were stained. In the immature as well as in the mature ovary the granulosa cells and oocytes of growing and large follicles — but not of small follicles — were stained. A particularly strong staining of the cytoplasm of the oocyte, healthy as well as atretic, was seen. All cells of the testis remained negative except for weakly stained residual bodies and late spermatids. At all ages the male ducts showed only weak staining, whereas in the female Müllerian duct the epithelium became strongly positive at puberty. The stroma of the Müllerian duct was positive during a transitory period around day 16 of fetal life in both sexes. One-dimensional gel immunoblotting of total protein from gonads, rete and ducts from immature and mature mice showed that only the two largest isoforms of NCAM (NCAM-A and NCAM-B) were present. The gonads and the rete of both sexes and the adult uterus expressed only NCAM-B, whereas NCAM-A was also detected in the adult epididymis. The present findings suggest that NCAM may be involved in the normal development and formation of both the gonads and ducts. In particular, NCAM may play a part in sustaining the integrity of the rete testis, thus ensuring the pathway for spermatozoa from the testis to the epididymis. Furthermore this cell adhesion molecule may also be important for follicular growth and differentiation. 相似文献