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101.
Genetic factors affecting the consistency and magnitude of changes in plasma cholesterol in response to dietary challenge 总被引:3,自引:0,他引:3
Humphries SE; Talmud PJ; Cox C; Sutherland W; Mann J 《QJM : monthly journal of the Association of Physicians》1996,89(9):671-680
We examined the role of common genetic variation in determining the
consistency and magnitude of change in plasma total cholesterol (TC) levels
in response to two separate changes from a high-saturated (SFA) to a
low-saturated/high-polyunsaturated-fat (PUFA) diet, in a group of
free-living healthy men and women. Consistent responders were defined as
those whose mean difference in the change in TC was within one SD of the
mean for all participants, and the remainder were defined as variable
responders. DNA was obtained from 55 individuals and genotype determined at
the apolipoprotein (apo) B locus (signal peptide, SP), apoCIII (C1100-T)
and lipoprotein lipase (LPL) gene loci (HindIII). In the 38 consistent
responders, the apoBSP24 allele was significantly more common than in the
17 individuals with a variable response (0.29 vs. 0.12; p < 0.05). No
other polymorphism showed a significant frequency difference between
groups. In the group as a whole, the correlation between the change in TC
level in response to the first and second dietary change was 0.28 (p =
0.05), but those with one or more apoB SP24 alleles and those with the
apoCIII genotype CC had a significantly higher correlation than those with
other genotypes (0.46 (p = 0.05) vs. 0.12 (NS) and 0.31 (p = 0.05) vs. 0.02
(NS), respectively). In the group as a whole, mean response left TC 10%
higher on the SFA than on the PUFA diet, and neither apoB nor apoCIII
genotypes affected the magnitude of this response. However, individuals
with the LPL HindIII genotype H+ H+ had a significantly smaller change in
mean TC in response to diet than those with one or more H- allele (9.3% vs.
14.4%; p = 0.03). Thus variation at the apoB and apoCIII loci affects the
consistency of response to change in dietary fat content, while variation
at the LPL gene locus affects magnitude of response.
相似文献
102.
Wierzbicki AS; Lumb PJ; Semra YK; Crook MA 《QJM : monthly journal of the Association of Physicians》1998,91(4):291-294
Lipid targets can be difficult to attain in familial hypercholesterolaemia.
To compare atorvastatin with simvastatin- fenofibrate and
simvastatin-cholestyramine therapy, we studied 54 patients with familial
hypercholesterolaemia over periods of 2-6 months on each therapeutic
regimen. The atorvastatin regimen reduced total cholesterol by 41.2 +/-
11.2%, LDL by 45.6 +/- 15.5%, triglycerides by 33.8 +/- 24.8%, and
increased HDL by 2.3 +/- 37.0%. Simvastatin- fenofibrate therapy achieved
reductions of 33.9 +/- 8.5% in cholesterol, 42.0 +/- 12.2% in LDL, 34.7 +/-
38.3% for triglycerides, and a 25.4 +/- 55.1% increase in HDL.
Simvastatin-cholestyramine gave a reduction of 31.3 +/- 11.8% in
cholesterol, 36.0 +/- 14.4% in LDL, 13.7 +/- 36.3% in triglycerides, and a
1.1 +/- 30.3% rise in HDL. The atorvastatin regimen was marginally but not
significantly better than simvastatin-fenofibrate in improving the LDL:HDL
ratio, LDL:apoB and and apolipoprotein B:A1 ratios. Eleven patients (20.4%)
had side- effects: two discontinued atorvastatin due to side-effects; two
patients had rashes; six had myalgia and two had diarrhoea.
Gastrointestinal side-effects were described in 16 (30.1%) patients on
simvastatin-cholestyramine therapy and four cases of myalgia (11.2%) were
seen with simvastatin-fenofibrate. In nine patients on atorvastatin (20.4%)
a 30% or greater fall in HDL was observed, compared to five patients with
resin therapy (9.2%) and two with fibrate therapy (5.5%). There were no
significant differences in liver or muscle biochemistry between the
regimens, but atorvastatin did raise transaminase and creatine kinase
concentrations significantly compared to pre-treatment values (p = 0.001).
Atorvastatin significantly improves the lipid profile in most patients
compared with other regimens. It has a comparable incidence of side-effects
to combination therapy regimens.
相似文献
103.
H-2 effects on cell-cell interactions in the response to single non-H-2 alloantigens. II. H-2 D region control of H-7.1-specific stimulator function in mixed lymphocyte culture and susceptibility to lysis by H-7.1- specific cytotoxic cells 下载免费PDF全文
The relative immunogenicity of the H-7.1 alloantigen has been shown in a previous communication to be regulated by a gene in the D region of the mouse major histocompatibility (H-2) complex. The level of relative immunogenicity was inferred from survival times of H-7.1-incompatible skin grafts donated by donors with different H-2 haplotype origins of H-2D region genes. In this communication we report the results of an extension of these previous investigations into the possible role of H-2D region genes in controlling the capacity of H-7.1-incompatible lymphocytes to stimulate H-7.1-speciflc mixed lymphocyte culture proliferation and generation of cytotoxic effector cells. The results reported herein demonstrate that the H-2D genotype of H-7.1-incompatible stimulator cells determines the relative H-7.1-specific capacity of those lymphocytes to stimulate H-7.1-specific proliferation of in vivo primed responder T cells in secondary mixed lymphocyte culture. H-2D(b)-bearing, H-7.l-incompatible stimulators were significantly more effective in stimulating H-7.1-specific proliferation than H-2D(d)-bearing stimulators. As expected, H-2D(b), H-7.1-in-compatible stimulators were also more effective than H-2D(d) a stimulators in generating H-7.1- specific cytotoxic effector cells. Further, the susceptibility of (51)Cr- labeled, H-7.1-incompatible lymphoblast targets to H-7.1-specific lysis was similarly regulated by an H-2D gene. Reciprocal H-2 restriction (F(1) cells are capable of killing only the cells bearing the immunizing cell parental H-2 haplotype) observed by other investigators for cytolysis of non-H-2-incompatible targets was not observed. H-2D a-bearing, H-7.1- incompatible stimulators stimulated generation of cytotoxic effectors capable of detectably lysing H-2D(b) but not H-2D(a)-bearing, H-7.1- incompatible targets. The impact of these observations on the proposed models for H-2 restriction of non-H-2 histocompatibility antigen-specific cytolysis is discussed. 相似文献
104.
Bo Yang Aroosa Malik Victoria Waidley Kellianne C. Kleeman Xiaoting Wu Elizabeth L. Norton David M. Williams Minhaj S. Khaja Whitney E. Hornsby 《The Journal of thoracic and cardiovascular surgery》2018,155(4):1360-1370.e1
Objective
To evaluate short-term outcomes following direct aortic root and arch repair in patients with acute type A aortic dissection (ATAAD) without technical adjuncts.Methods
Between 2012 and 2016, 94 consecutive patients with ATAAD underwent surgical repair, including aortic root repair (n = 45), root replacement (n = 39), or no root procedure (n = 10). Aortic root repair was achieved by running approximation of the dissected aortic wall circumferentially at the sinotubular junction and reinforcing the coronary ostia with 5-0 Prolene. The aortic root and arch were anastomosed to the Dacron graft with 5-0 Prolene without Teflon felt or biological glue.Results
Postoperative new-onset myocardial infarction, stroke, renal failure, and complete heart block occurred in 0%, 4%, 13%, and 0% of patients, respectively, whereas 30-day mortality was 4%. The incidences of permanent neurologic deficit and renal failure were 1% and 2%, respectively. Up to 5 years, the aortic root repair group was free from residual or recurrent aortic root dissection, major change in the aortic root diameter, and moderate to severe aortic regurgitation; the entire cohort was free of anastomotic pseudoaneurysm and reoperation for proximal aortic pathology or significant change in diameter of the aortic arch and descending thoracic aorta. Overall survival was 85% at 4 years and was significantly enhanced in the aortic root repair group compared with the Bentall group (n = 24) (93% vs 57%; P = .035).Conclusions
Direct aortic root and arch repair with approximation of the aortic wall without use of technical adjuncts is safe and effective for patients with ATAAD. If warranted, preservation of the native aortic valve should be considered for a potential survival benefit. 相似文献105.
OSTLERE L; WARNER T; MEUNIER PJ; HULME P; HESP R; WATTS RWE; REEVE J 《QJM : monthly journal of the Association of Physicians》1991,79(3):503-515
Two patients with Type 1 (adult) Gaucher's disease and majorskeletal involvement with multiple fractures have been treatedwith the second generation bisphosphonate pamidronate for extensiveperiods. There was evidence of an immediate reduction in boneresorption, with increased calcium absorption (delayed in Patient1), improved calcium balance and maintained or improved bonedensity indices in the axial and peripheral skeleton. Therewas no evidence of immediate relapse on treatment cessation.No toxic effects of pamidronate treatment were identified andsubjective skeletal pain diminished in both patients. Histomorphometryof transiliac bone biopsies obtained before the start of treatment,after double in vivo tetracycline labelling, represents oneof the earliest reports of the quantitative findings in iliacbone invaded by Gaucher cells. 相似文献
106.
Wang W Wang L Endoh A Hummelke G Hawks CL Hornsby PJ 《The Journal of endocrinology》2005,184(1):85-94
In order to establish whether there are differences in DNA-binding proteins between zona fasciculata (ZF) and zona reticularis (ZR) cells of the human adrenal cortex, we prepared nuclear extracts from separated ZF and ZR cells. The formation of DNA-protein complexes was studied using an element in the first intron of the type I and type II 3beta-hydroxysteroid dehydrogenase genes (HSD3B1 and HSD3B2). Using the element in the HSD3B2 gene as a probe, a complex (C1) was formed with extracts from ZF cells but was formed only at a low level with ZR cell extracts. Another pair of complexes (C2/C3) was formed with both ZF and ZR cell extracts. The ZF-specific protein forming C1 was enriched by column chromatography on DEAE-Sepharose and carboxymethyl-Sepharose. Oligonucleotide competition analysis on the enriched fraction gave results consistent with those obtained on the unfractionated material. A further enrichment was brought about by passing the protein over an oligonucleotide affinity column based on the HSD3B2 element. The protein bound to the column was identified as alpha-enolase by mass spectrometry. Although alpha-enolase is a glycolytic enzyme, it binds to specific DNA sequences and has been found to be present in nuclei of various cell types. We performed immunohistochemistry on sections of adult human adrenal cortex and found alpha-enolase to be located in nuclei of ZF cells but to be predominantly cytoplasmic in ZR cells. Transfection of an alpha-enolase expression vector into NCI-H295R human adrenocortical cells increased HSD3B2 promoter activity, suggesting a possible functional role for this protein in regulation of HSD3B2 expression. 相似文献
107.
FcR gamma-chain is essential for both surface expression and function of human Fc gamma RI (CD64) in vivo 总被引:5,自引:0,他引:5
van Vugt MJ; Heijnen AF; Capel PJ; Park SY; Ra C; Saito T; Verbeek JS; van de Winkel JG 《Blood》1996,87(9):3593-3599
Most Ig receptors exist as hetero-oligomeric complexes with separate ligand binding (alpha) and signal transducing (beta, gamma, or zeta) subunits. For Fc gamma RIIIa and Fc epsilon RI, association with the FcR gamma-chain is essential for surface expression. However, the human high affinity IgG receptor, hFc gamma RI, was found to be surface- expressed by itself in transient transfection models. We have now analyzed the integrity of hFc gamma RI expression in more detail in stable transfectants. In vitro we noted that, in the absence of FcR gamma-chain, surface expression of hFc gamma RI rapidly declined to background levels, in both IIA1.6 B cells and NIH3T3 fibroblasts. The effect of FcR gamma-chain on hFc gamma RI surface expression in vivo was evaluated by using two newly generated transgenic mouse lines, selectively expressing hFc gamma RI on myeloid cells. These transgenic mice were crossed with FcR gamma-chain-deficient mice. Analysis of blood monocytes and peritoneal macrophages showed that surface expression of hFc gamma RI was reduced by approximately 80%. The remaining approximately 20% of receptors were still capable of binding IgG-opsonized RBC, suggesting FcR gamma-chain not to be critical for hFc gamma RI ligand-binding capacity. Importantly, however, hFc gamma RI signaling capacity was lost in FcR gamma-chain-deficient cells. No phagocytosis could be observed using either ligand sensitized (EA- IgG2a) or CD64-targeted erythrocytes (using a bispecific antibody) in both hFc gamma RI transgenic lines. This documents the FcR gamma-chain to be indispensable for both surface membrane expression and function of human Fc gamma RI in vivo. 相似文献
108.
Mycobacterial Infections After Renal Transplantation 总被引:5,自引:0,他引:5
HIGGINS RM; CAHN AP; PORTER D; RICHARDSON AJ; MITCHELL RG; HOPKIN JM; MORRIS PJ 《QJM : monthly journal of the Association of Physicians》1991,78(2):145-153
Mycobacterial infections occurred in 11 of 633 (1.7 per cent)recipients of successful renal transplants. There were no casesof tuberculosis in patients receiving chemoprophylaxis, butamongst those who did not receive prophylaxis disease occurredin six of the 27 (22 per cent) high-risk patients. The majorcause of morbidity during treatment was renal allograft rejection,largely due to reduction in immunosuppressive drug therapy. 相似文献
109.
WY Khoder AJ Becker B Schlenker S Tritschler PJ Bastian CG Stief 《European journal of medical research》2009,14(7):320-322
Introduction
Rectal polypectomy causes thinning (or even perforation) of the rectal wall in addition to thermic injury at the polypectomy site.Case report
We present a rare case of spontaneous rectal perforation after uncomplicated nerve sparing endoscopic extraperitoneal radical prostatectomy in a patient with a previous history of rectal polypectomy at the perforation site. The patient could be treated conservatively. There was complete healing of the fistula without any effect on functional results. This Conservative therapy for such rectal perforations is indicated if the patient''s general condition remains stable without any signs of infection.Conclusions
Polypectomy is an important risk factor for rectal perforation during nsEERPE. Adequate time interval should be given to allow healing and avoid adding further thermal wall damage which may obscure healing leading to complications like fistula. Conservative therapy for small missed rectal perforations constitutes an attractive, feasible and non invasive treatment entity. Following this principle we have not faced this complication in following similar cases. 相似文献110.
Jones LW Liang Y Pituskin EN Battaglini CL Scott JM Hornsby WE Haykowsky M 《The oncologist》2011,16(1):112-120