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C Bruton

Publications and source records attributed to C Bruton.

12 recordsLinked to original sources

Soluble tumor necrosis factor receptor abrogates myocardial inflammation but not hypertrophy in cytokine-induced cardiomyopathy.

BACKGROUND: Transgenic mice with cardiac-specific overexpression of tumor necrosis factor (TNF)-alpha develop dilated cardiomyopathy. The present study was designed to evaluate therapeutic effects of adenovirus-mediated neutralization of TNF-alpha on this model. METHODS AND RESULTS: An adenovirus encoding the 55-kDa TNF receptor-IgG fusion protein (AdTNFRI) was injected intravenously into 6-week-old transgenic mice, which resulted in high levels of TNFRI in both plasma and myocardium. AdTNFRI did not reverse cardiomegaly but abrogated myocardial inflammation. Furthermore, AdTNFRI blocked the myocardial expression of intercellular adhesion molecule-1 and downstream cytokines, including interleukin-1beta and monocyte chemotactic protein-1. Downregulation of alpha-myosin heavy chain was restored by the treatment, whereas upregulation of beta-myosin heavy chain was not reversed. In contrast, the downregulation of sarcoplasmic reticulum Ca(2+)-ATPase and phospholamban was normalized by AdTNFRI. Echocardiographic measurements showed that left ventricular end-systolic diameter was significantly larger in transgenic mice than in control mice, and this increase was reversed by the AdTNFRI treatment. However, left ventricular wall thickening was not reversed. CONCLUSIONS: These results suggest that anti-TNF therapy may hold promise in the treatment of end-stage heart failure.

Adenoviridae↗

The use of high dose rate endobronchial brachytherapy to palliate symptomatic endobronchial recurrence of previously irradiated bronchogenic carcinoma.

Thirty-eight patients were treated with high dose rate endobronchial brachytherapy to palliate symptoms (cough, hemoptysis, fever, and/or shortness of breath) caused by endobronchial of previously irradiated (greater than or equal to 5000 cGy) bronchogenic carcinoma. The dose per fraction was 600 cGy at a radius of 1 cm from the center of the linear path of the source, and each patient received three fraction, each fraction separated by a 1-week interval. Twenty-nine patients (76%) had symptomatic improvement, 16 with complete and 13 with partial relief of symptoms. The likelihood of symptom relief was greater in those patients who had extra-bronchial tumor measuring less than 5 cm (15/15) compared to those with extra-bronchial tumor measuring greater than or equal to 5 cm (2/8). The median duration of symptom relief was 7.5 months. Repeat bronchoscopy done 3 months after brachytherapy revealed that 41% (11/27) had complete tumor regression and another 41% (11/27) had partial regression. Nine of 14 patients with post-obstructive atelectasis/pneumonitis had radiographic improvement. Twelve patients (32%) died from massive hemoptysis occurring 2-56 weeks (median 10 weeks) after brachytherapy. Location of the recurrence was the most important predictor of pulmonary hemorrhage. It occurred only in patients with recurrence in the right upper lobe, right mainstem, or left upper lobe bronchus. Whether this high rate of fatal pulmonary hemorrhage was a real phenomenon or a statistical fluke of small numbers remains an unanswered question.

Brachytherapy↗

A "mock up" of schizophrenia: temporal lobe epilepsy and schizophrenia-like psychosis.

Schizophrenia-like psychoses occur more frequently than expected in patients with chronic temporal lobe epilepsy. We have analyzed pathological and clinical data from a series (n = 249) of temporal lobectomies to determine the factors that may relate to the development of schizophrenia-like psychosis. Schizophrenia-like psychoses did not occur at random; they were significantly associated with lesions that (1) originated in the fetus or perinatally, (2) affected neurons in the medial temporal lobe, and (3) gave an early age of first fit. Gangliogliomas--developmental lesions of the medial temporal lobe containing aberrant neurons--were disproportionately (p less than 0.001) associated with risk of psychosis. Schizophrenia-like psychoses arising preoperatively occurred more often (p = 0.1) with left-sided lesions. Asymmetry of lesion was not present in cases with postoperative psychoses. These findings are of interest in relation to recent studies suggesting that the structural abnormalities found in the brains of schizophrenics arise during fetal brain development.

Adult↗

The occult aftermath of boxing.

The repeated head trauma experienced by boxers can lead to the development of dementia pugilistica (DP)--punch drunk syndrome. The neuropathology of DP in a classic report by Corsellis et al describes the presence of numerous neurofibrillary tangles in the absence of plaques, in contrast to the profusion of tangles and plaques seen in Alzheimer's disease (AD). The DP cases used in that report were re-investigated with immunocytochemical methods and an antibody raised to the beta-protein present in AD plaques. We found that all DP cases with substantial tangle formation showed evidence of extensive beta-protein immunoreactive deposits (plaques). These diffuse "plaques" were not visible with Congo-red or standard silver stains. The degree of beta-protein deposition was comparable to that seen in AD. Our data indicate that the present neuropathological description of DP (tangles but no plaques) should be altered to acknowledge the presence of substantial beta-protein deposition (plaques). The molecular markers present in the plaques and tangles of DP are the same as those in AD. Similarities in clinical symptoms, distribution of pathology and neurochemical deficits also exist. Epidemiological studies have shown that head injury is a risk factor in AD. It is probable that DP and AD share common pathogenic mechanisms leading to tangle and plaque formation.

Adult↗

Neurofibrillary tangles in some cases of dementia pugilistica share antigens with amyloid beta-protein of Alzheimer's disease.

Formalin-fixed, paraffin-embedded temporal lobe sections from eight former boxers' brains were examined using an immunohistochemical method with antibodies to amyloid beta protein. In accord with recent observations in Alzheimer's disease, significant numbers of beta-protein immunoreactive neurofibrillary tangles (NFT) were observed in three cases. Most of these immunoreactive NFTs appeared to be tombstone tangles, although not all such tangles were stained. This immunoreaction was completely abolished by preincubation of antibodies with synthetic beta-protein peptides, and the identity of the immunostained NFTs was confirmed by polarization microscopy of sections counterstained with Congo red. However, it is not yet clear if the beta-protein antigens are, in fact, an integral part of paired helical filaments. These observations, together with our recent finding of beta-immunoreactive plaque-like lesions in dementia pugilistica, also emphasize the many similarities in pathology between this condition and Alzheimer's disease.

Adult↗

A demonstration of the advantages of immunostaining in the quantification of amyloid plaque deposits.

Extracellular amyloid deposits are a feature of both Alzheimer type dementia and the 'normal' aging process. Quantification of amyloid plaque deposits may well be useful in distinguishing between the senescent changes associated with 'normal' aging and the pathological processes underlying dementia. To determine the most reliable and reproducible method for visualisation of the amyloid we have compared conventional silver staining techniques with beta-amyloid immunocytochemistry on a large sample of post-mortem brain tissue from both demented (n = 15, age range 60-87) and non-demented (n = 65, age range 14-99) patients. The degree of amyloid deposition was rated on a four point scale and ratings for the two techniques were significantly correlated (P less than 0.01). However, the immunocytochemical approach has a number of distinct advantages for quantification. The antibody to beta-amyloid is highly specific and does not stain neurofibrillary tangles or background features, it is considerably more sensitive than silver staining in highlighting diffuse amyloid deposits and, perhaps most importantly, it produces high contrast staining which allows easier image digitisation and subsequent computer image analysis.

Adolescent↗

C-reactive protein and serum amyloid P component in the plaice (Pleuronectes platessa L.), a marine teleost, are homologous with their human counterparts.

C-reactive protein and serum amyloid P component were isolated from serum of the plaice (Pleuronectes platessa L.), a murine teleost. The isolation was based on their calcium-dependent binding affinity for pneumococcal C-polysaccharide and for agarose, respectively. These specificities are the same as those of human C-reactive protein and serum amyloid P component, respectively, and we have previously reported that the plaice molecules resemble human C-reactive protein and serum amyloid P component in their electron microscopic appearance. We describe here estimation of the molecular weights of plaice C-reactive protein and serum amyloid P component and their subunits, and analysis of their amino acid composition, glycosylation and partial amino-terminal amino acid sequences. The results establish that plaice C-reactive protein and serum amyloid P component are homologous with each other and with their human counterparts and indicate that there has been stable conservation of this protein family throughout vertebrate evolution.

Amino Acid Sequence↗

Isolation and characterization of C-reactive protein and serum amyloid P component in the rat.

C-reactive protein (RP) and serum amyloid P component (SAP) have been identified for the first time in rat serum and isolated by calcium-dependent affinity chromatography. Rat CRP closely resembled human CRP in its amino acid composition, in having five subunits per molecule and in its electron microscopic appearance as a pentameric annular disc. It differed, however, from all other mammalian CRP's characterised hitherto in being a glycoprotein bearing a single complex oligosaccharide on each polypeptide subunit. Furthermore one pair of tis subunits per molecule was linked by a interchain disulphide bridges whereas in other animals the subunits of both CRP and SAP are all non-covalently associated. The serum concentration of CRP in normal healthy laboratory rats and in specific pathogen-free rats was 300-600 micrograms/ml which is much greater than has been described in any other species and exceeds even maximal acute phase levels of CRP in man. Following injections of casein or croton oil, serum CRP levels rose to a maximum of about 900 micrograms/ml. Rat CRP bound to pneumococcal C-polysaccharide (CPS( but, in marked contrast to the behaviour of CRP from man, rabbit and marine teleost fish, it did not precipitate with CPS solutions, agglutinate CPS-coated sheep erythrocytes or initiate complement activation. Rat SAP, like SAP of other species, was a glycoprotein but unlike them it was composed only of a single pentameric disc not two such discs interacting face-to-face. The normal level of SAP in rat serum was 20-50 micrograms/ml, very similar to the levels seen in man, and it did not behave as an acute phase reactant in response to casein or croton-oil injections. In this respect it resembled human SAP but differed from murine SAP which is a major acute phase reactant.

Amino Acids↗

Gram-scale purification of methionyl-tRNA and tyrosyl-tRNA synthetases from Escherichia coli.

A procedure is presented for the purification of 3 g of homogeneous methionyl-tRNA synthetase and 1 g of homogeneous tyrosyl-tRNA synthetase from 50 kg batches of Escherichia coli. The procedure permits the isolation of many enzymes simultaneously and the elution positions of seven other aminoacyl-tRNA synthetases, catalase, rhodanese, phosphofructokinase, elongation factor Tu and cytochrome b-562 are indicated. The problems of extraction work on this scale are discussed.

Amino Acyl-tRNA Synthetases↗