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M D Barber

Publications and source records attributed to M D Barber.

At least 19 recordsLinked to original sources

Disordered metabolic response with cancer and its management.

The metabolic changes in cancer cachexia appear to be mediated by a complex network of proinflammatory cytokines, neuroendocrine hormones, neurotransmitters, eicosanoids, and tumor-derived factors produced by the body in response to the tumor and by the tumor itself. The relative importance of these various mediator pathways in relation to either the anorexia or hypermetabolism associated with weight loss in cancer remains to be fully elucidated. Our current understanding suggests that proinflammatory mediators may indeed be a valid target for therapeutic intervention. Trials attempting to modify the inflammatory response to cancer with the hope of improving appetite and reversing catabolism and perhaps thereby improving qualityof life and survival are currently underway.

Animals↗

Characteristics of patients with pancreatic cancer expressing a novel cancer cachectic factor.

BACKGROUND: Recently a novel tumour-derived cachectic factor was identified in the murine MAC16 colonic adenocarcinoma model of cachexia. This factor, provisionally named proteolysis-inducing factor (PIF), was subsequently identified in the urine of weight-losing patients with cancer but not in the urine of weight-stable patients with cancer or weight-losing controls with benign disease. This study determined the nutritional characteristics of patients with pancreatic cancer who excrete PIF in the urine and investigated the relationship between PIF and the acute-phase protein response. METHODS: PIF was isolated from urine by precipitation and ultrafiltration and was then identified by Western blotting of nitrocellulose membranes using a previously developed monoclonal antibody. Full nutritional assessment of patients was undertaken at the same time as urine collection. RESULTS: PIF was detected in the urine of 80 per cent of patients (n = 55). These patients had a significantly greater total weight loss and rate of weight loss than patients whose urine did not contain PIF (median 12.5 (range 4-43) kg versus 4.5 (0-14) kg; P < 0.0002). No association was evident between the presence of PIF in patients' urine and serum C-reactive protein (CRP) concentration. Furthermore, the accelerated weight loss associated with PIF expression also appeared to be independent of the acute-phase response. Overall the presence of PIF was not associated with reduced survival, although the previously reported association between raised CRP concentration and poor prognosis was confirmed. CONCLUSION: PIF is associated with an accelerated rate of weight loss in patients with a tumour of the pancreatic head. This observation appears to be independent of the effect of an increased hepatic acute-phase protein response.

Aged↗

Metabolic response to feeding in weight-losing pancreatic cancer patients and its modulation by a fish-oil-enriched nutritional supplement.

Weight-losing patients with advanced cancer often fail to gain weight with conventional nutritional support. This suboptimal response might be explained, in part, by an increased metabolic response to feeding. It has been suggested that eicosapentaenoic acid (EPA) can modify beneficially the metabolic response to cancer. The aim of the present study was to examine the metabolic response to feeding in cancer and the effects of an EPA-enriched oral food supplement on this response. A total of 16 weight-losing, non-diabetic patients with unresectable pancreatic adenocarcinoma and six healthy, weight-stable controls were studied by indirect calorimetry in the fasting and fed states. Body composition was estimated by bioimpedence analysis. Cancer patients were then given a fish-oil-enriched nutritional supplement providing 2 g of EPA and 2550 kJ daily, and underwent repeat metabolic study after 3 weeks of such supplementation. At baseline, resting energy expenditure whether expressed per kg body weight, lean body mass or body cell mass was significantly greater in the cancer patients compared with controls. Fat oxidation was significantly higher in the fasting state in cancer patients [median 1.26 g.kg(-1).min(-1) (interquartile range 0.95-1.38)] than in controls [0.76 g.kg(-1). min(-1) (0.62-0.92); P<0.05]. Over the 4 h feeding period, changes in insulin and glucose concentrations in cancer patients suggested relative glucose intolerance. In response to oral meal feeding, the percentage change in the area under the curve of energy expenditure was significantly lower in the cancer patients [median 7.9% (interquartile range 3.4-9.0)] than in controls [12.6% (9.9-15.1); P<0.01]. After 3 weeks of the EPA-enriched supplement, the body weight of the cancer patients had increased and the energy expenditure in response to feeding had risen significantly [9.6% (6. 3-12.4)], such that it was no different from baseline healthy control values. Similarly, fasting fat oxidation fell to 1.02 g. kg(-1).min(-1) (0.8-1.18), again no longer significantly different from baseline healthy control values. While weight-losing patients with advanced pancreatic cancer have an increased resting energy expenditure and increased fat oxidation, the energy cost of feeding is, in fact, reduced. Provision of a fish-oil-enriched nutritional supplement results in some normalization of the metabolic response in both the fasted and fed states, in association with an improvement in nutritional status.

Aged↗

Pancreatic cancer as a model: inflammatory mediators, acute-phase response, and cancer cachexia.

Patients with pancreatic cancer frequently develop the syndrome of cancer cachexia. Pro-inflammatory cytokines have been strongly implicated in the pathogenesis of this syndrome. In patients with pancreatic cancer an acute-phase response (an index of pro-inflammatory cytokine activity) is associated with accelerated weight loss, hypermetabolism, anorexia, and a shortened duration of survival. However, little is known about the primary significance of the acute-phase response in terms of altered hepatic export protein synthesis rates and its potential impact on the body's nitrogen economy. In a recent series of studies on weight-losing pancreatic cancer patients with hypoalbuminemia we have demonstrated albumin synthesis to be unaltered whereas fibrinogen synthesis is increased two- to threefold compared with healthy controls. Because of the mismatch in amino acid composition between the body's main labile amino acid reserve (skeletal muscle) and that of acute-phase proteins, these results lend support to the concept that in pancreatic cancer the reprioritization of body protein metabolism during an acute-phase response may well be a significant factor in the loss of lean tissue in these patients.

Acute-Phase Proteins↗

Accuracy of clinical assessment of paravaginal defects in women with anterior vaginal wall prolapse.

OBJECTIVE: The objective of this study was to determine the accuracy of clinical assessment of paravaginal defects in women with anterior vaginal wall prolapse. STUDY DESIGN: A retrospective chart review of all women undergoing surgery for anterior vaginal wall prolapse during the years of 1994 to 1996 identified operative notes that described the surgical assessment of paravaginal support. These surgical findings were compared with the preoperative clinical assessment. Clinical parameters that predicted poor correlation were identified. Statistical analysis used the chi(2) test. RESULTS: One hundred seventeen patients had surgery for anterior vaginal prolapse. Seventy had documentation of an intraoperative paravaginal support evaluation. Of these, 44 patients had vaginal procedures, and 26 had abdominal procedures. All patients had at least stage 2 prolapse before surgery, and all were noted to have excellent pelvic support 4 to 6 weeks after surgery. The prevalence of paravaginal defects at surgery was 47% on the right and 41% on the left. The sensitivity and negative predictive value for the clinical assessment for paravaginal defects were good on both the right and left sides, whereas the specificity and positive predictive values were poor. Stage of prolapse, previous hysterectomy, or previous anterior colporrhaphy did not significantly affect the accuracy of the clinical examination in predicting fascial defects. However, previous retropubic urethropexy did significantly decrease the accuracy of the clinical examination in predicting right paravaginal defects (P <.01) but not left. CONCLUSION: Although preoperative clinical assessment for paravaginal defects is useful, it does not substitute for careful intraoperative evaluation for endopelvic fascial defects.

Adult↗

The effect of an oral nutritional supplement enriched with fish oil on weight-loss in patients with pancreatic cancer.

Previous studies have suggested that administration of oral eicosapentaenoic acid (EPA) will stabilize weight in patients with advanced pancreatic cancer. The aim of the present study was to determine if a combination of EPA with a conventional oral nutritional supplement could produce weight gain in these patients. Twenty patients with unresectable pancreatic adenocarcinoma were asked to consume two cans of a fish oil-enriched nutritional supplement per day in addition to their normal food intake. Each can contained 310 kcal, 16.1 g protein and 1.09 g EPA. Patients were assessed for weight, body composition, dietary intake, resting energy expenditure (REE) and performance status. Patients consumed a median of 1.9 cans day(-1). All patients were losing weight at baseline at a median rate of 2.9 kg month(-1). After administration of the fish oil-enriched supplement, patients had significant weight-gain at both 3 (median 1 kg, P= 0.024) and 7 weeks (median 2 kg, P = 0.033). Dietary intake increased significantly by almost 400 kcal day(-1) (P = 0.002). REE per kg body weight and per kg lean body mass fell significantly. Performance status and appetite were significantly improved at 3 weeks. In contrast to previous studies of oral conventional nutritional supplements in weight-losing cancer patients, this study suggests that an EPA-enriched supplement may reverse cachexia in advanced pancreatic cancer.

Adenocarcinoma↗

Two polymorphisms of the tumour necrosis factor gene do not influence survival in pancreatic cancer.

Polymorphisms of the tumour necrosis factor (TNF) gene have been related to TNF production and outcome in a variety of inflammatory and malignant diseases. Proinflammatory cytokines and the inflammatory state appear to affect outcome in pancreatic cancer. Thus, the present study examined the TNFB and TNF-308 polymorphisms for their relationship to the inflammatory state and survival in pancreatic cancer. Sixty-four patients with advanced pancreatic cancer and 101 healthy subjects were genotyped for each polymorphism. Serum concentrations of the two TNF receptors and C-reactive protein (CRP) were measured in 45 of the cancer patients with no evidence of infection or jaundice, 1 month after surgical intervention. There was no difference in distribution of genotypes between the patient and control groups. There was no association between any genotype and concentrations of any of the measured inflammatory mediators. While those with an elevated CRP concentration had significantly poorer survival, there was no association between either TNF genotype and survival. This study found no association between TNF genotype and the inflammatory state or survival in advanced pancreatic cancer. Other cytokines may be more important than TNF in determining the inflammatory state and disease progress in pancreatic cancer.

Adult↗

Fish oil-enriched nutritional supplement attenuates progression of the acute-phase response in weight-losing patients with advanced pancreatic cancer.

The presence of an acute-phase protein response (APPR) has been suggested to shorten survival and contribute to weight loss in patients with pancreatic cancer. Fatty acids derived from fish oil have been shown to alter proinflammatory cytokine production and acute-phase protein synthesis in vitro. The present study was designed to determine the effects of a fish oil-enriched nutritional supplement on the concentrations of a range of individual acute-phase proteins (APP) in patients with advanced pancreatic cancer. In a sequential series, 18 patients with pancreatic cancer received the supplement (providing 2 g eicosapentaenoic acid and 1 g docosahexaenoic acid/d) for 3 wk while another 18 received full supportive care alone. Six healthy subjects served as additional controls. Acute-phase proteins were measured before and after the 3-wk intervention period in cancer patients. At baseline, albumin, transferrin and pre-albumin were significantly reduced and fibrinogen, haptoglobin, alpha-1-acid glycoprotein, alpha-1-antitrypsin, ceruloplasmin and C-reactive protein (CRP) were significantly elevated in the cancer patients compared with healthy controls, reflecting their roles as negative and positive acute phase proteins, respectively. In the supplemented cancer group, the only significant change in APP concentrations over the 4-wk study period was an increase in transferrin. In the control cancer group there were further significant reductions in albumin, transferrin and pre-albumin, and a significant increase in CRP concentration. These results suggest that many positive and negative APP are altered in advanced pancreatic cancer. The APPR tends to progress in untreated patients but may be stabilized by the administration of a fish oil-enriched nutritional supplement. This may have implications for reducing wasting in such patients.

Acute-Phase Proteins↗

Changes in nutritional, functional, and inflammatory markers in advanced pancreatic cancer.

Weight loss and the acute-phase response have been associated with poor quality of life and survival in advanced pancreatic cancer; however, little information is available on changes in these factors over time and their interrelationships. This study examined changes in weight, Karnofsky performance status, C-reactive protein (CRP), and serum albumin in 25 patients with advanced pancreatic cancer given supportive symptomatic treatment only. Patients were assessed at approximately monthly intervals on a total of 70 occasions, allowing assessment of changes over 37 intervals. Overall, patients had a median weight loss of 2.3 kg/28 days. Median CRP levels rose by 15 mg/l, and serum albumin fell by 1 g/l on average over 28 days. Karnofsky performance status fell by 4 points every 28 days. The nine patients assessed close to death were compared with the 13 assessed close to diagnosis. The increase in CRP level and fall in weight and performance status were significantly greater within eight weeks of death than within eight weeks of diagnosis. Among patients close to diagnosis, 13% had an elevated CRP compared with 100% of those close to death. In multivariate analysis, Karnofsky performance status was significantly associated with percent weight loss and CRP levels. These data further implicate the acute-phase protein response as being associated with the progressive weight loss seen in patients with advanced pancreatic cancer. Changes appear to accelerate close to death. Moreover, the development of cachexia is associated with a reduction in patients' functional capacity.

Adult↗

Relationship of serum levels of interleukin-6, soluble interleukin-6 receptor and tumour necrosis factor receptors to the acute-phase protein response in advanced pancreatic cancer.

The level of the acute-phase response is a major predictor of survival in patients with advanced pancreatic cancer. This study examines the association between the acute-phase protein response, as determined by serum C-reactive protein, and serum levels of interleukin-6, soluble interleukin-6 receptor and the soluble tumour necrosis factor receptors in patients with pancreatic cancer. Thirty-four blood samples were collected from 13 patients with advanced pancreatic cancer. Samples were also collected from six healthy subjects. Levels of C-reactive protein, interleukin-6, soluble interleukin-6 receptor and soluble tumour necrosis factor receptors 55 and 75 were measured by indirect ELISA. Serum levels of C-reactive protein, interleukin-6 and soluble tumour necrosis factor receptors 55 and 75 were significantly higher in cancer patients than in controls. Levels of serum soluble interleukin-6 receptor were not significantly different between the two groups. In cancer patients, a significant positive association was found between the level of the acute-phase protein response and serum levels of interleukin-6, soluble tumour necrosis factor receptor 55 and soluble tumour necrosis factor receptor 75. No association was found between levels of soluble interleukin-6 receptor and any other factor. There is no significant relationship between the level of soluble interleukin-6 receptor and the acute-phase protein response in vivo and the biological role of soluble interleukin-6 receptor in the chronic inflammatory component of cachexia remains unclear.

Acute-Phase Reaction↗

Biological evaluation of a lipid-mobilizing factor isolated from the urine of cancer patients.

We have previously shown human lipid-mobilizing factor (LMF) to be homologous with the plasma protein Zn-alpha2-glycoprotein in amino acid sequence, electrophoretic mobility, and immunoreactivity. In this study, both LMF and Zn-alpha2-glycoprotein have been shown to stimulate glycerol release from isolated murine epididymal adipocytes with a comparable dose-response profile. Both LMF and Zn-alpha2-glycoprotein caused a stimulation of adenylate cyclase in murine adipocyte plasma membranes in a GTP-dependent process, with maximum stimulation at 0.1 microM GTP and with saturation at protein concentrations of >5 microg/assay. Administration of LMF to exbreeder male mice over a 89-h period produced a decrease in body weight without a change in food and water intake. Body composition analysis showed a 42% reduction in carcass lipid when compared with controls. Treatment of ob/ob mice with human LMF over a 160-h period also produced a decrease in body weight, with a 19% reduction in carcass fat, without a change in body water or nonfat mass. Serum levels of glycerol and 3-hydroxybutyrate were significantly increased, as was oxygen uptake by interscapular brown adipose tissue, providing evidence of increased lipid mobilization and utilization. Human white adipocytes responded to both LMF and isoprenaline to the same extent, although the maximal response was lower than that for murine white adipocytes. These results suggest that LMF not only has the capacity to induce lipid mobilization and catabolism in mice, but it also has the potential to exert similar effects in cachectic cancer patients.

Adenylyl Cyclases↗

New reference allelic ladders to improve allelic designation in a multiplex STR system.

This paper reports the composition of a new reference allelic ladder mixture for use with a multiplex DNA profiling system consisting of six short tandem repeat loci. The loci included in this mixture are HUMTH01, D21S11, D18S51, D8S1179, HUMVWAF31/A, HUMFIBRA/FGA and an amelogenin sex test. Sequence analysis of individual ladder alleles was carried out and allelic designations made in accordance with the recommendations of the International Society of Forensic Haemogenetics (1992; 1994). A series of rare alleles which increase the range of alleles previously reported were identified. By including some of the rare alleles into the ladder marker system, we have significantly improved the ability to identify new alleles in unknown samples.

Alleles↗

Recurrent appendicitis.

BACKGROUND: The existence of appendiceal inflammation which resolves spontaneously without surgical intervention has long been controversial. This study was undertaken, therefore, to determine the existence and incidence of recurrent appendicitis. METHODS: The existence of a large database of patients with abdominal pain enabled a retrospective study of the casenotes of the 1084 patients who had an inflammed appendix removed between January 1982 and December 1991 in a Scottish District General Hospital. Sixty consecutive patients who had a normal appendix removed during this period were also studied. RESULTS: Seventy-one patients (6.5 per cent) attended the accident and emergency department 89 times with symptoms and signs compatible with appendicitis which resolved spontaneously between 3 weeks and 12 years before an attendance during which an inflamed appendix was removed. There were significant differences in clinical signs and symptoms (using the Alvarado scoring system) between patients whose symptoms resolved, those with a normal and those with an inflamed appendix. Those who had a normal appendix removed were more likely to be female than those with resolving symptoms (67 versus 42 per cent, P < 0.01). CONCLUSION: Recurrent appendicitis exists and affects at least 6.5 per cent of those who ultimately have an inflamed appendix removed.

Adolescent↗