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1.
Med Hypotheses ; 136: 109530, 2020 Mar.
Article in English | MEDLINE | ID: mdl-31862686

ABSTRACT

BACKGROUND: The hierarchical model of stem cell genesis is based on the idea that the number of cell divisions between the zygote and fully differentiated epithelial cells is kept close to the minimum, which is log to the base 2 of the total number of cells produced in a human lifetime. The model assumes the orderly progression of stem cell divisions requires precise control at every stage in development. If the orderly progression is maintained then cancer will be rare. A prediction of the model is that if the orderly progression of the stem cell hierarchy is disturbed by trauma, ulceration or inflammation then cancer will occur. HYPOTHESIS: Bacterial induced inflammation in breast ducts disturbs the stem cell hierarchy and is a cause of breast cancer. EVIDENCE: Mammalian milk is not sterile. It contains a range of bacteria, derived endogenously by the entero-mammary circulation. The dominant flora consists of lactose fermenting bacteria. Pregnancy and breast feeding reduce the risk of subsequent breast cancer. The implication is that a lactose fermenting bacterial flora in breast ducts is protective. Malignant and benign breast tissue contains bacteria derived endogenously, but studies so far have not revealed a specific flora associated with malignancy. Periodontitis is associated with oral, oesophageal, colonic, pancreatic, prostatic and breast cancer. The pathogenic bacteria which cause periodontitis spread endogenously to cause inflammation at other epithelial sites. Meta-analysis of epidemiological studies shows that the consumption of yoghurt is associated with a reduction in the risk of breast cancer. CONCLUSION: The hypothesis, although not proven, is supported by the available evidence. Lactose fermenting bacteria protect but pathogenic bacteria which induce inflammation raise the risk of breast cancer. The consumption of yoghurt also appears to be protective.


Subject(s)
Bacterial Infections/diagnosis , Breast Neoplasms/microbiology , Breast Neoplasms/physiopathology , Inflammation/microbiology , Stem Cells/cytology , Breast/microbiology , Cell Division , Disease Progression , Female , Humans , Lactation , Milk, Human/microbiology , Pregnancy
2.
Stat Methods Med Res ; 25(2): 741-53, 2016 04.
Article in English | MEDLINE | ID: mdl-23136147

ABSTRACT

An important assumption in many linear mixed models is that the conditional distribution of the response variable is normal. This assumption is violated when the models are fitted to an outcome variable that counts the number of correctly answered questions in a questionnaire. Examples include investigations of cognitive decline where models are fitted to Mini Mental State Examination scores, the most widely used test to measure global cognition. Mini Mental State Examination scores take integer values in the 0-30 range, and its distribution has strong ceiling and floor effects. This article explores alternative distributions for the outcome variable in mixed models fitted to mini mental state examination scores from a longitudinal study of ageing. Model fit improved when a beta-binomial distribution was chosen as the distribution for the response variable.


Subject(s)
Cognition , Cognitive Dysfunction/diagnosis , Linear Models , Statistics, Nonparametric , Aged , Aged, 80 and over , Aging , Female , Humans , Longitudinal Studies , Male , Surveys and Questionnaires
3.
Gut ; 58(8): 1104-12, 2009 Aug.
Article in English | MEDLINE | ID: mdl-19398439

ABSTRACT

OBJECTIVE: Ileocaecal resection (ICR) is common in Crohn's disease. Inflammation and fibrosis frequently recur at the site of anastomosis or in the small intestine (SI). No animal models of postsurgical inflammation and fibrosis exist. A model of ICR was developed in interleukin 10 (IL10) null and wild-type (WT) mice to test the hypothesis that ICR promotes postsurgical inflammation and fibrosis in the SI or anastomosis of genetically susceptible IL10 null, but not WT or germ-free (GF)-IL10 null mice. METHODS: GF-IL10 null mice were conventionalised (CONV) and 3 weeks later randomised to ICR, transection (T) or no treatment (NoTx). Age-matched conventionally raised (CONV) WT and GF-IL10 null mice received ICR, T or NoTx. Animals were killed 28 days later. Histological scoring, real-time PCR for tumour necrosis factor alpha and collagen, and immunostaining for CD3(+) T cells assessed inflammation and fibrosis. RESULTS: After ICR, CONV-IL10 null, but not CONV-WT mice, developed significant inflammation and fibrosis in the SI and inflammation in anastomosis compared with NoTx or T controls. Fibrosis occurred in the anastomosis of both CONV-IL10 null and CONV-WT mice following ICR. GF-IL10 null mice developed little or no inflammation or fibrosis in the SI or anastomosis after ICR. CONCLUSIONS: ICR in CONV-IL10 null mice provides a new animal model of postsurgical inflammation and fibrosis in the SI and anastomosis. Absence of inflammation and fibrosis in the SI of CONV-WT and GF-IL10 null mice following ICR indicates that postsurgical small bowel disease occurs only in genetically susceptible IL10 null mice and is bacteria dependent.


Subject(s)
Cecum/surgery , Crohn Disease/surgery , Disease Models, Animal , Ileum/surgery , Postoperative Complications/microbiology , Anastomosis, Surgical , Animals , Collagen/biosynthesis , Collagen/genetics , Crohn Disease/metabolism , Crohn Disease/microbiology , Fibrosis , Genetic Predisposition to Disease , Interleukin-10/deficiency , Intestine, Small/microbiology , Intestine, Small/pathology , Mice , Mice, Knockout , RNA, Messenger/genetics , Recurrence , Tumor Necrosis Factor-alpha/biosynthesis , Tumor Necrosis Factor-alpha/genetics , Up-Regulation
4.
Oncogene ; 26(33): 4833-41, 2007 Jul 19.
Article in English | MEDLINE | ID: mdl-17297444

ABSTRACT

Intestinal injury or chronic inflammation induce cytokines that promote crypt regeneration and mucosal repair. If excessive or prolonged, such mechanisms may increase colon cancer risk. Factors that terminate or limit cytokine action in intestinal epithelial cells (IEC) may protect against crypt hyperplasia and neoplasia. We hypothesized that suppressor of cytokine signaling-3 (SOCS3) is such a factor. Mice with Vilin-promoter/Cre-recombinase (VC)-mediated IEC-specific SOCS3 gene disruption (VC/HO), WT/HO littermates with floxed but intact SOCS3 genes and VC/WT mice were studied. Colon was examined after acute dextran sodium sulfate (DSS)-induced mucosal injury or after azoxymethane (AOM) and chronic DSS. Signaling pathways were examined in colon, cultured IEC or colon cancer cell lines. VC/HO mice showed no basal phenotype. After acute DSS, VC/HO exhibited enhanced crypt proliferation and crypt hyperplasia and reduced transforming growth factor (TGF) beta expression in colon. Inflammation and mucosal damage were similar across genotypes. Following AOM/DSS, VC/HO mice had increased size, number and load of colonic tumors and increased STAT3 and nuclear factor-kappa B (NF-kappaB) activation in colon. In vitro, SOCS3 overexpression reduced proliferation, IL-6-mediated STAT3 activation and tumor necrosis factor (TNF) alpha-mediated NF-kappaB activation. We conclude that cytokine induction of SOCS3 normally provides an intrinsic mechanism to limit injury-induced crypt hyperproliferation and inflammation-associated colon cancer by regulating both STAT3 and NF-kappaB pathways.


Subject(s)
Cell Proliferation , Colon/metabolism , Colonic Neoplasms/pathology , Suppressor of Cytokine Signaling Proteins/genetics , Animals , Blotting, Western , Caco-2 Cells , Cell Line , Cell Line, Tumor , Colon/pathology , Colonic Neoplasms/genetics , Colonic Neoplasms/metabolism , Female , Gene Expression , Humans , Inflammation/genetics , Inflammation/metabolism , Inflammation/pathology , Interleukin-6/pharmacology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , NF-kappa B/metabolism , Phosphorylation/drug effects , Reverse Transcriptase Polymerase Chain Reaction , STAT1 Transcription Factor/metabolism , STAT3 Transcription Factor/metabolism , Suppressor of Cytokine Signaling 3 Protein , Suppressor of Cytokine Signaling Proteins/physiology , Tumor Burden , Tumor Necrosis Factor-alpha/pharmacology
5.
Genes Immun ; 7(7): 592-9, 2006 Oct.
Article in English | MEDLINE | ID: mdl-16943797

ABSTRACT

Systemic lupus erythematosus is an autoimmune disease in which complex interactions between genes and environmental factors determine the disease phenotype. We have shown that genes from the non-autoimmune strains 129 and C57BL/6 (B6), commonly used for generating gene-targeted animals, can induce a lupus-like disease. Here, we conducted a genome-wide scan analysis of a cohort of (129 x B6)F2 C1q-deficient mice to identify loci outside the C1qa locus contributing to the autoimmune phenotype described in these mice. The results were then confirmed in a larger dataset obtained by combining the data from the C1q-deficient mice with data from previously reported wild-type mice. Both analyses showed that a 129-derived interval on distal chromosome 1 is strongly linked to autoantibody production. The B6 genome contributed to anti-nuclear autoantibody production with an interval on chromosome 3. Two regions were linked to glomerulonephritis: a 129 interval on proximal chromosome 7 and a B6 interval on chromosome 13. These findings demonstrate that interacting loci between 129 and B6 mice can cause the expression of an autoimmune phenotype in gene-targeted animals in the absence of any disrupted gene. They also indicate that some susceptibility genes can be inherited from the genome of non-autoimmune parental strains.


Subject(s)
Lupus Erythematosus, Systemic/genetics , Animals , Antibodies, Antinuclear/biosynthesis , Chromosome Mapping , Complement C1q/deficiency , Complement C1q/genetics , Female , Lupus Erythematosus, Systemic/immunology , Mice , Mice, Inbred C57BL , Mice, Knockout , Phenotype , Quantitative Trait Loci , Species Specificity
6.
Rheumatology (Oxford) ; 45(9): 1062-7, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16769771

ABSTRACT

Defining the polymorphisms that contribute to the development of complex genetic disease traits is a challenging, although increasingly tractable problem. Historically, the technical difficulties in conducting association studies across the entire human genome are such that murine models have been used to generate candidate genes for analysis in human complex diseases, such as SLE. In this article we discuss the advantages and disadvantages of this approach and specifically address some assumptions made in the transition from studying one species to another, using lupus as an example. These issues include differences in genetic structure and genetic organisation which are a reflection on the population history. Clearly there are major differences in the histories of the human population and inbred laboratory strains of mice. Both human and murine genomes do exhibit structure at the genetic level. That is to say, they comprise haplotypes which are genomic regions that carry runs of polymorphisms that are not independently inherited. Haplotypes therefore reduce the number of combinations of the polymorphisms in the DNA in that region and facilitate the identification of disease susceptibility genes in both mice and humans. There are now novel means of generating candidate genes in SLE using mutagenesis (with ENU) in mice and identifying mice that generate antinuclear autoimmunity. In addition, murine models still provide a valuable means of exploring the functional consequences of genetic variation. However, advances in technology are such that human geneticists can now screen large fractions of the human genome for disease associations using microchip technologies that provide information on upwards of 100,000 different polymorphisms. These approaches are aimed at identifying haplotypes that carry disease susceptibility mutations and rely less on the generation of candidate genes.


Subject(s)
Lupus Erythematosus, Systemic/genetics , Mice, Inbred NZB , Models, Animal , Polymorphism, Genetic , Animals , Genetic Predisposition to Disease , Genome , Haplotypes , Humans , Mice , Species Specificity
7.
Clin Exp Immunol ; 139(2): 245-56, 2005 Feb.
Article in English | MEDLINE | ID: mdl-15654823

ABSTRACT

Intestinal dendritic cells (DC) are likely to regulate immunity to gut microflora, but little is known about their responses to bacterial antigens. Therefore, DC from normal murine colon were characterized and their cytokine responses to components of Gram-negative and/or Gram-positive bacteria assessed. Cells were obtained by digestion of colonic tissue and contained DC that were identified by flow cytometry as CD11c(+) major histocompatibility complex (MHC) class II(+) cells. Purified DC were obtained by immunomagnetic separation plus cell sorting. DC had the morphology of immature myeloid cells, were endocytically active, expressed low levels of co-stimulatory molecules and stimulated a weak allogeneic mixed leucocyte reaction. Analysis of flow cytometry data by a sensitive subtraction method allowed measurement of production of interleukin (IL)-12 and IL-10 by small numbers of gut DC by intracellular staining. Fewer than 5% of unstimulated DC produced either IL-10 or IL-12. IL-10 production was significantly up-regulated following stimulation with Bifidobacteria longum, but not after exposure to lipopolysaccharide (LPS) or Streptococcus faecium. In contrast, colonic DC produced IL-12 in response to both LPS and B.longum. Thus, colonic DC can produce both IL-12 and IL-10 following bacterial stimulation. Cell wall components from different bacteria stimulate distinct responses and may direct immune responses differentially in the gut.


Subject(s)
Antigens, Bacterial/immunology , Bifidobacterium/immunology , Colon/immunology , Dendritic Cells/immunology , Interleukin-10/biosynthesis , Interleukin-12/biosynthesis , Animals , CD11c Antigen/immunology , Cell Proliferation , Cell Separation/methods , Cells, Cultured , Enterococcus faecium/immunology , Female , Lipopolysaccharides/pharmacology , Mice , Mice, Inbred BALB C
8.
Clin Exp Immunol ; 138(1): 39-46, 2004 Oct.
Article in English | MEDLINE | ID: mdl-15373903

ABSTRACT

The New Zealand Black (NZB) mouse strain is a model of autoimmune haemolytic anaemia (AHA) and systemic lupus erythematosus (SLE), characterized by the production of anti-red blood cell (RBC) antibodies and anti-nuclear antibodies (ANA), respectively. A linkage analysis was carried out in an (NZB x BALB/c) F(2) cross in order to identify loci involved in the production of both anti-RBC IgM and IgG antibodies. These regions of linkage were compared with linkage data to ANA from the same cohort and other linkage analyses involving New Zealand mice. Four previously described NZB loci linked to anti-RBC antibodies were confirmed, and eight novel loci linked to this trait were also mapped: five of which were of NZB origin, and three derived from the non-autoimmune BALB/c background. A comparison between loci linked with anti-RBC antibodies and ANA demonstrated many that co-localize, suggesting the presence of genes that result in the general breaking of tolerance to self-antigen. Furthermore, the observation that some loci were associated only with the anti-RBC response suggests an antigen specific mechanism in addition to a general breaking of tolerance. A locus linked with anti-RBC antibodies and ANA on distal chromosome 7 in this cohort is orthologous to one on the q arm of human chromosome 11, a region linked to AHA and ANA in human SLE.


Subject(s)
Anemia, Hemolytic, Autoimmune/immunology , Antibody Formation/immunology , Erythrocytes/immunology , Lupus Erythematosus, Systemic/immunology , Anemia, Hemolytic, Autoimmune/genetics , Anemia, Hemolytic, Autoimmune/pathology , Animals , Antibodies, Antinuclear/genetics , Antibodies, Antinuclear/immunology , Antibody Formation/genetics , Chromosomes, Mammalian/genetics , Chromosomes, Mammalian/immunology , Genetic Linkage/genetics , Genetic Linkage/immunology , Immunoglobulin G/blood , Immunoglobulin M/blood , Liver/immunology , Liver/pathology , Lupus Erythematosus, Systemic/genetics , Lupus Erythematosus, Systemic/pathology , Mice , Mice, Inbred BALB C , Mice, Inbred NZB
9.
Am J Kidney Dis ; 37(6): 1209-15, 2001 Jun.
Article in English | MEDLINE | ID: mdl-11382690

ABSTRACT

Patients with end-stage renal failure are a high-risk group for atherosclerotic cardiovascular disease and commonly have dyslipidemia as a major factor. Dietary manipulation is the recommended first line of therapy for reducing lipid levels in people with normal renal function; however, complex dietary requirements of dialysis-treated patients with end-stage renal failure impose significant constraints. In this study, we evaluated the effect of trying to comply with established lipid-lowering recommendations superimposed on our normally prescribed dialysis diet over 14 weeks in stable subjects treated with either hemodialysis (HD) or chronic peritoneal dialysis (PD). Of 306 dialysis patients screened, 75 subjects were enrolled; 8 subjects did not complete the study. In the remainder, HD subjects (n = 41) decreased saturated fat intakes by 18% overall and cholesterol intakes by 16%. This was associated with a decrease in total cholesterol levels from 232 +/- 8 to 209 +/- 4 mg/dL (mean +/- SEM; P = 0.007) and low-density lipoprotein cholesterol levels from 147 +/- 4 to 131 +/- 4 mg/dL (P = 0.009). However, energy intakes decreased by almost 10%. There were no statistically significant changes in PD patients (n = 26). Only 24.4% of HD (10 of 41 patients) and 15.4% of PD patients (4 of 26 patients) normalized their lipid levels. Considerable problems were encountered in maintaining compliance with the modified dialysis diets. This study shows that if adhered to, properly constructed dialysis diets are close to optimal lipid-lowering recommendations. Further dietary manipulation is difficult, leads to little benefit in the majority, and is accompanied by added problems of adherence. We conclude that the vast majority of dyslipidemic patients with end-stage renal failure require pharmacological therapy.


Subject(s)
Dietary Fats/administration & dosage , Energy Intake/drug effects , Kidney Failure, Chronic/diet therapy , Lipid Metabolism , Peritoneal Dialysis , Renal Dialysis , Body Mass Index , Carbohydrate Metabolism , Fats/metabolism , Female , Humans , Hyperlipidemias/diet therapy , Hyperlipidemias/therapy , Kidney Failure, Chronic/therapy , Male , Middle Aged , Patient Dropouts , Proteins/drug effects , Proteins/metabolism , Treatment Outcome
10.
J Immunol ; 166(8): 4958-67, 2001 Apr 15.
Article in English | MEDLINE | ID: mdl-11290774

ABSTRACT

Dendritic cells (DC) in the colon may regulate intestinal immunity but remain poorly characterized. In this study a CD11c(+)HLA-DR(+)lin(-) (CD3(-)CD14(-)CD16(-)CD19(-)CD34(-)) population has been identified by flow cytometry in cells obtained by rapid collagenase digestion of human colonic and rectal biopsies. These day 0 (d0) CD11c(+)HLA-DR(+)lin(-) cells comprised approximately 0.6% of the mononuclear cells obtained from the lamina propria, were endocytically active, and had the phenotype of immature DC; they were CD40(+) and expressed low levels of CD83 and CD86, but little or no CD80 or CD25. Similar d0 DC populations were isolated from the colonic mucosa of healthy controls and from both inflamed and noninflamed tissue from patients with Crohn's disease. The lamina propria also contained a population of cells capable of migrating out of biopsies during an overnight culture and differentiating into mature DC with lower levels of endocytic activity and high cell surface expression of CD40, CD80, CD86, CD83, and CD25. This mature DC population was a potent stimulator of an allogeneic mixed leukocyte (MLR). Overnight culture of cells isolated by enzymatic digestion on d0 yielded DC with a phenotype intermediate between that of the d0 cells and that of the cells migrating out overnight. Overnight culture of colonic cells in which DC and HLA-DR(+)lin(+) cells were differentially labeled with FITC-dextran suggested that some of the maturing DC might differentiate from HLA-DR(+)lin(+) progenitors. This study presents the first analysis of the phenotype, maturational status, and migratory activity of human gut DC.


Subject(s)
Cell Movement/immunology , Colon/cytology , Colon/immunology , Dendritic Cells/cytology , Adult , Aged , Aged, 80 and over , Cell Count , Cell Differentiation/immunology , Cell Lineage/immunology , Cell Separation , Cells, Cultured , Colon/pathology , Colon/ultrastructure , Crohn Disease/immunology , Crohn Disease/pathology , Dendritic Cells/pathology , Dendritic Cells/ultrastructure , Endocytosis/immunology , Female , HLA-DR Antigens/biosynthesis , Humans , Immunophenotyping , Inflammatory Bowel Diseases/immunology , Inflammatory Bowel Diseases/pathology , Intestinal Mucosa/cytology , Intestinal Mucosa/immunology , Intestinal Mucosa/pathology , Intestinal Mucosa/ultrastructure , Male , Middle Aged , Prospective Studies
11.
Clin Biochem ; 34(1): 77-81, 2001 Feb.
Article in English | MEDLINE | ID: mdl-11239520

ABSTRACT

OBJECTIVES: Although monitoring of cyclosporin (CsA) is standard clinical practice postrenal transplantation, mycophenolic acid (MPA) concentrations are not routinely measured. There is evidence that a relationship exists between MPA area under the concentration-time curve (AUC) and rejection. In this study, a retrospective analysis was undertaken of 27 adult renal transplant recipients. METHODS: Patients received CsA and MPA therapy and had a four-point MPA AUC investigation. The relationship between MPA AUC performed in the first week after transplantation, as well as median trough cyclosporin concentrations, and clinical outcomes in the first month posttransplant were evaluated. RESULTS: A total of 12 patients experienced biopsy proven rejection (44.4%) and 4 patients had gastrointestinal adverse events (14.8%). A statistically significant relationship was observed between the incidence of biopsy proven rejection and both MPA AUC (p = 0.02) and median trough CsA concentration (p = 0.008). No relationship between trough MPA concentration and rejection was observed (p = 0.21). Only 3 of 11 (27%) patients with an MPA AUC > 30 mg x h/L and a median trough CsA > 175 microg/L experienced acute rejection, compared with a 56% incidence of rejection for the remaining 16 patients. Patients who experienced adverse gastrointestinal events had significantly lower MPA AUC (p = 0.04), but median trough CsA concentrations were not significantly different (p = 0.24). Further, 3 of these 4 patients had rejection episodes. CONCLUSIONS: In addition to standard CsA monitoring, we propose further investigation of the use of a 4-point sampling strategy to predict MPA AUC in the first week posttransplant, which may facilitate optimization of mycophenolate mofetil dose at a time when patients are most vulnerable to acute rejection.


Subject(s)
Cyclosporine/pharmacology , Graft Rejection/drug therapy , Immunosuppressive Agents/pharmacology , Kidney Transplantation/methods , Mycophenolic Acid/pharmacology , Adult , Aged , Area Under Curve , Cyclosporine/adverse effects , Digestive System/drug effects , Dose-Response Relationship, Drug , Female , Humans , Immunosuppressive Agents/adverse effects , Male , Middle Aged , Mycophenolic Acid/adverse effects , Retrospective Studies , Time Factors , Treatment Outcome
12.
Transplantation ; 70(1): 149-52, 2000 Jul 15.
Article in English | MEDLINE | ID: mdl-10919592

ABSTRACT

BACKGROUND: In this report we describe a malignant lymphoma of donor origin inadvertently transplanted into two renal allograft recipients, despite standard comprehensive donor screening. The successful clearance of the tumor from both patients and a novel method of surveillance are detailed. METHODS: Initial management consisted of withdrawal of immunosuppression to promote rejection of the allograft and the transplanted tumor in both patients, followed by graft removal. Peripheral blood microchimerism was assessed in both recipients using nested polymerase chain reaction to detect the DYZ3 gene on the Y chromosome (donor male, recipients female). RESULTS: Although microchimerism was detected on day 6 after transplantation and day 1 after explantation, repeat peripheral blood examination at 1, 3, and 6 months after explantation demonstrated no microchimerism. Both patients remain well at 12 months and have been relisted for transplantation. CONCLUSION: Despite inadvertent transplantation of a previously undiagnosed malignancy of donor origin, the recipients' immune response was able to eliminate donor tumor cells after the withdrawal of immunosuppression. Repeated surveillance of peripheral blood from both recipients, using a novel application of the technique of nested polymerase chain reaction to amplify donor DNA, demonstrated no persistence of donor cells, supporting effective eradication of the donor malignancy.


Subject(s)
Kidney Transplantation/adverse effects , Lymphoma, B-Cell/therapy , Tissue Donors , Aged , Chimera , Female , Humans , Immunosuppression Therapy , Lymphoma, B-Cell/diagnosis , Lymphoma, B-Cell/etiology , Male , Middle Aged , Polymerase Chain Reaction , Transplantation, Homologous
13.
J Immunol ; 164(6): 3420-5, 2000 Mar 15.
Article in English | MEDLINE | ID: mdl-10706738

ABSTRACT

Pertussis toxin (PTX) is a potent ancillary adjuvant used to elicit several different autoimmune diseases, including experimental allergic encephalomyelitis (EAE). To delineate the genetics of PTX effect in EAE, we mapped EAE-modifying (eae-m) loci in cohorts of backcross mice immunized with and without PTX. In this study, we analyzed the genetic basis of EAE susceptibility and severity and the intermediate phenotypes of mononuclear cell infiltration, suppuration, and demyelination. In animals immunized with PTX, one major locus, eae9, controls disease susceptibility and severity. Eae9 also regulates the extent of mononuclear cell infiltration of the spinal cord in male mice. Without PTX, five eae-m loci were noted, including three new loci in intervals on chromosomes 8 (eae14), 10 (eae17), and 18 (eae18). Taken together, these results suggest that eae9 controls the effects of PTX in EAE susceptibility, and is capable of overriding the other genetic checkpoints in the pathogenesis of this disease.


Subject(s)
Encephalomyelitis, Autoimmune, Experimental/genetics , Encephalomyelitis, Autoimmune, Experimental/immunology , Genetic Predisposition to Disease/genetics , Pertussis Toxin , Virulence Factors, Bordetella/immunology , Animals , Brain/pathology , Crosses, Genetic , Encephalomyelitis, Autoimmune, Experimental/etiology , Encephalomyelitis, Autoimmune, Experimental/pathology , Female , Genetic Markers , Genetic Predisposition to Disease/etiology , Histamine/immunology , Linear Models , Male , Mice , Mice, Inbred C57BL , Quantitative Trait, Heritable , Severity of Illness Index , Spinal Cord/pathology , Virulence Factors, Bordetella/toxicity
14.
Perit Dial Int ; 20(6): 715-21, 2000.
Article in English | MEDLINE | ID: mdl-11216565

ABSTRACT

OBJECTIVE: To determine the influence of an elevated body mass index (BMI) on cardiovascular outcomes and survival in peritoneal dialysis (PD) patients. DESIGN: Prospective, observational study of a prevalent PD cohort at a single center. SETTING: Tertiary care institutional dialysis center. PATIENTS: The study included all patients with a BMI of at least 20 who had been receiving PD for at least 1 month as of 31 January 1996 (n = 43). Patients were classified as overweight [BMI > 27.5; mean +/- standard error of mean (SEM): 32.1 +/- 1.1; n = 14] or normal weight (BMI 20-27.5; mean +/- SEM: 23.8 +/- 0.4; n = 29). OUTCOME MEASURES: Patient survival and adverse cardiovascular events (myocardial infarction, congestive cardiac failure, cerebrovascular accident, and symptomatic peripheral vascular disease) were recorded over a 3-year period. RESULTS: At baseline, no significant differences were seen between the groups in clinical, biochemical, nutritional, or echocardiographic parameters, except for a lower dietary protein intake (0.97 +/- 0.10 g/kg/day vs 1.44 +/- 0.10 g/kg/day, p = 0.004) and a higher proportion of well-nourished patients by subjective global assessment (100% vs 72%, p < 0.05) in the overweight group. After 3 years of follow-up, 29% of overweight patients and 69% of normal-weight patients had died (p < 0.05). Using a Cox proportional hazards model, a BMI greater than 27.5 was shown to be an independent positive predictor of patient survival, with an adjusted hazard ratio (HR) of 0.09 [95% confidence interval (CI): 0.01-0.85; p < 0.05]. However, being overweight did not significantly influence myocardial infarction-free survival (adjusted HR: 0.33; 95% CI: 0.07-1.48; p = 0.15) or combined adverse cardiovascular event-free survival (adjusted HR: 0.67; 95% CI: 0.23-1.93; p = 0.46). CONCLUSIONS: Obesity conferred a significant survival advantage in our PD population. Obese patients should therefore not be discouraged from receiving PD purely on the basis of BMI. Moreover, maintaining a higher-than-average BMI to preserve "nutritional reserve" may help to reduce the mortality and morbidity rates associated with PD.


Subject(s)
Body Mass Index , Kidney Failure, Chronic/mortality , Kidney Failure, Chronic/therapy , Obesity/complications , Peritoneal Dialysis , Aged , Cardiovascular Diseases/etiology , Female , Humans , Kidney Failure, Chronic/complications , Male , Middle Aged , Prognosis , Survival Rate
15.
Transplantation ; 69(5): 794-9, 2000 Mar 15.
Article in English | MEDLINE | ID: mdl-10755528

ABSTRACT

BACKGROUND: Patients over age 60 constitute half of all new patients accepted into the renal replacement therapy programs in Australia. However, the optimal treatment of their end-stage renal disease remains controversial. The aim of the present study was to compare survival for dialysis and renal transplantation in older patients who were rigorously screened and considered eligible for transplantation. METHODS: The study cohort consisted of 174 consecutive patients over 60 who were accepted on to the Queensland cadaveric renal transplant waiting list between January 1, 1993 and December 31, 1997. Follow-up was terminated on October 1, 1998. Data were analyzed on an intention-to-transplant basis using a Cox regression model with time-varying explanatory variables. An alternative survival analysis was also performed, in which patients no longer considered suitable for transplantation were censored at the time of their removal from the waiting list. RESULTS: There were 67 patients receiving a renal transplant, whereas the other 107 continued to undergo dialysis. These two groups were well matched at baseline with respect to age, gender, body mass index, renal disease etiology, comorbid illnesses, and dialysis duration and modality. The overall mortality rate was 0.096 per patient-year (0.131 for dialysis and 0.029 for transplant, P<0.001). Respective 1-, 3- and 5-year survivals were 92%, 62%, and 27% for the dialysis group and 98%, 95%, and 90% (P<0.01) for the transplant group. Patients in the transplant group had an adjusted hazard ratio 0.16 times that of the dialysis group (95% confidence interval 0.06-0.42). If patients were censored at the time of their withdrawal from the transplant waiting list, the adjusted hazard ratio was 0.24 (95% confidence interval 0.09-0.69). CONCLUSIONS: Renal transplantation seems to confer a substantial survival advantage over dialysis in patients with end-stage renal failure who are rigorously screened and considered suitable for renal transplantation.


Subject(s)
Aging/physiology , Kidney Transplantation , Renal Replacement Therapy , Uremia/therapy , Aged , Cohort Studies , Female , Follow-Up Studies , Humans , Kidney Transplantation/statistics & numerical data , Male , Patient Dropouts , Proportional Hazards Models , Renal Replacement Therapy/statistics & numerical data , Survival Analysis
16.
Clin Pharmacol Ther ; 66(5): 492-500, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10579476

ABSTRACT

BACKGROUND: Mycophenolic acid kinetics have been reported to vary after renal transplantation, and mycophenolic acid area under the concentration-time curve (AUC) is the best predictor of suppression of graft rejection. METHODS: To determine whether mycophenolic acid kinetics vary after renal transplantation and to examine the potential role of enterohepatic recirculation, we investigated the kinetics of mycophenolic acid and mycophenolic acid glucuronide on days 2, 5, and 28 after transplantation in 10 kidney transplant recipients (male/female ratio, 1.5; mean age, 41.7 +/- 5.0 years) given 1 g mycophenolate mofetil twice a day. To facilitate therapeutic drug monitoring, we examined a limited sampling strategy for estimating 12-hour mycophenolic acid [AUC(0-12)]. RESULTS: The mean +/- SE AUC(0-12) for mycophenolic acid on day 28 was 38.5 +/- 1.6 mg x h/L, with a secondary peak 4 to 8 hours after dosing that was attributable to enterohepatic recirculation. Marked variability was shown in the kinetic profile of mycophenolic acid among patients across the three sampling days. Mycophenolic acid AUC(0-12) was positively predicted by both serum creatinine (P = .01) and serum albumin (P = .03) but not by time after transplantation, body weight, or trough concentration. Limited sampling (at 0, 1, 3, and 6 hours) accounted for 84.1% of the variability in the mycophenolic acid AUC(0-12) data and predicted the AUC(0-12) closely (r2 = 0.954) when evaluated in 10 different kidney transplant recipients. CONCLUSIONS: Mycophenolic acid AUC(0-12) is predicted by serum albumin and creatinine after kidney transplantation, and the AUC(0-12) may be determined during the early posttransplant period while the patient remains hospitalized with use of a limited sampling strategy to facilitate therapeutic drug monitoring.


Subject(s)
Enzyme Inhibitors/pharmacokinetics , Kidney Transplantation , Mycophenolic Acid/pharmacokinetics , Adult , Analysis of Variance , Area Under Curve , Creatinine/blood , Enzyme Inhibitors/blood , Female , Humans , Male , Middle Aged , Mycophenolic Acid/blood , Serum Albumin/metabolism , Time Factors
18.
Clin Transplant ; 13(6): 520-5, 1999 Dec.
Article in English | MEDLINE | ID: mdl-10617243

ABSTRACT

BACKGROUND: With current techniques, renal failure patients are now able to regain near-normal health following renal transplantation. However, the development of premature cardiovascular disease is a major problem. Dyslipidaemia may be an important contributor to this. The use of lipid lowering agents in renal allograft recipients has been limited by potential interaction of these agents with the now widely used immunosuppressive agent, cyclosporine. AIM: This study was designed to investigate efficacy and safety of simvastatin in subjects taking either cyclosporine or azothioprine post renal transplantation. METHODS: Fifty-one subjects (32 females, 19 males -- mean age 51 +/- 12.5 yr) who were at least 1 yr post transplant, had creatinine < or = 2.5 mmol/L and a total cholesterol > or = 6 mmol/L were enrolled in a prospective, double-blind, placebo-controlled study. After an initial 10-wk dietary period, the last 4 wk on placebo, subjects were randomised to receive either 5 mg simvastatin/d for 6 wk followed by 10 mg simvastatin/d for 6 wk, or matching placebo. After this 12-wk double-blind phase, there was an open-label phase when all subjects were treated with 10 mg simvastatin/d for a period of 36 wk. RESULTS: Compared to placebo, 5 mg simvastatin/d significantly decreased total cholesterol by 20% (p < 0.01), low-density lipoprotein cholesterol (LDL cholesterol) by 29% (p < 0.01), and Apolipoprotein B (ApoB) by 26% (p < 0.01). Increasing simvastatin to 10 mg/d did not lead to further significant changes. But high-density lipoprotein cholesterol (HDL cholesterol) increased by 9% (p < 0.01) and Apolipoprotein A1 (ApoA1) by 7% (p < 0.01) only on 10 mg simvastatin/d. During the open-label phase, subjects previously randomised to placebo achieved similar significant changes to their lipoprotein profile. The benefits achieved from simvastatin were maintained to the end of the study. There were three withdrawals from the study, all from the simvastatin/ cyclosporine group. Two subjects had musculoskeletal pain and 1 had abdominal pain. Minor adverse events were similar in both the simvastatin- and placebo-treated groups. CONCLUSION: Low-dose simvastatin is an effective and well-tolerated agent in the treatment of dyslipidaemia in renal allograft recipients.


Subject(s)
Hyperlipidemias/drug therapy , Hyperlipidemias/etiology , Hypolipidemic Agents/therapeutic use , Kidney Transplantation/adverse effects , Simvastatin/therapeutic use , Adolescent , Adult , Aged , Double-Blind Method , Female , Humans , Male , Middle Aged , Prospective Studies
19.
Transplantation ; 66(5): 655-61, 1998 Sep 15.
Article in English | MEDLINE | ID: mdl-9753350

ABSTRACT

BACKGROUND: A kidney transplant recipient inadvertently contracted donor-origin melanoma, which was found to be very advanced at presentation. Withdrawal of immunosuppression failed to induce rejection, and interferon-alpha was required. When florid allograft rejection was in progress, the allograft was removed, before it was recognized that the transplanted melanoma was not being simultaneously rejected. METHODS: Subsequent immunotherapy was required, which largely recapitulated treatment of recognized value in autologous melanoma and included interferon-alpha, use of cultured melanoma cells as tumor vaccine, pooled allogeneic cell vaccination, and adoptive immunotherapy using lymphokine-activated killer cells. RESULTS: Prolonged immunotherapy eradicated the widespread malignancy, and the patient went on to a successful second renal transplant, with follow-up of over 24 months. CONCLUSIONS: This unique case demonstrates the successful cure of advanced transplanted melanoma through the use of immunotherapy, which did not require sophisticated tumor vaccine technology, and successful retransplantation.


Subject(s)
Kidney Transplantation/adverse effects , Melanoma/pathology , Tissue Donors , Transplantation Immunology , Adult , Antineoplastic Agents/therapeutic use , Female , Humans , Immunosuppressive Agents/therapeutic use , Interferon alpha-2 , Interferon-alpha/therapeutic use , Kidney Transplantation/immunology , Male , Melanoma/immunology , Middle Aged , Recombinant Proteins
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