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P Mallon

Publications and source records attributed to P Mallon.

10 recordsLinked to original sources
PubMed2006

Increased cholecystectomy rate in the laparoscopic era: a study of the potential causative factors.

BACKGROUND: It has been suggested that an increased cholecystectomy rate in the laparoscopic era may be due to a reduced threshold for surgery or diagnostic confusion with irritable bowel syndrome (IBS). This study aims to determine the validity of these suggestions. METHODS: Questionnaires were sent to patients who had undergone cholecystectomy between 1988-1990 (open) and 1998-2000 (laparoscopic). Patients were asked about abdominal pain, fatty food intolerance, jaundice, and indigestion pre- and postoperatively. Questionnaires included Rome II criteria for the diagnosis of IBS and SF-36 quality-of-life data. Histological severity of gallbladder disease was assessed using a standard scoring system. RESULTS: A total of 124 of 196 patients in the open group and 264 of 400 patients in the laparoscopic group replied. There was no difference between the groups in gender, age at surgery, IBS incidence, or quality-of-life scores. The laparoscopic group reported a lower incidence of preoperative fat intolerance (45.8 vs 58.1%, p < 0.05) and a higher incidence of persistent postoperative abdominal pain (27.3 vs 17.7%, p < 0.05). Mean histopathology severity scores were higher in the open group (4.42 vs 3.95, p < 0.01). CONCLUSIONS: Increased cholecystectomy rate in the laparoscopic era cannot be attributed to diagnostic confusion with IBS. However, a reduction in the threshold for surgery may have contributed to the increased rate of cholecystectomy.

Abdominal Pain↗
PubMed2005

Genetic analysis of susceptibility to endometrial adenocarcinoma in the BDII rat model.

Most cancers are genetically complex and heterogeneous, a serious obstacle to identifying specific genes underlying the disease. If inbred animal models are used, then both the genetic constitution and environmental influences can be carefully controlled. Females of the BDII inbred rat strain are genetically predisposed to endometrial cancer; more than 90% of virgin BDII females will develop endometrial adenocarcinoma (EAC) during their life span. BDII females were crossed to males from inbred strains with low EAC incidence (SPRD or BN). When F(1) males were backcrossed to BDII females to generate N(1) populations of offspring, about one fourth of the female progeny developed EAC. With transmission disequilibrium test analysis, significant association was detected in three chromosomal regions (on RNO1, RNO11, and RNO17) in the SPRD crosses and in the short arm of RNO20 in the BN crosses. It appears that several susceptibility genes with minor but cooperating effects are responsible for the susceptibility. Furthermore, it seems clear from the interstrain crosses not only that the onset of tumors depends on the presence of susceptibility alleles from the EAC-prone BDII strain, but also that tumor development is affected by the contribution of a genetic component derived from the nonsusceptible strains.

Adenocarcinoma↗
PubMed2001

Fatal portal hypertension, liver failure, and mitochondrial dysfunction after HIV-1 nucleoside analogue-induced hepatitis and lactic acidaemia.

Acute hepatitis with lactic acidosis is a life-threatening but reversible toxic effect on mitochondria of HIV-1 nucleoside-analogue treatment. We report fatal portal hypertension, liver failure, and persistent mitochondrial dysfunction in a man aged 65 years with HIV-1 infection who had recovered from nucleoside-analogue-induced acute hepatitis and lactic acidaemia more than 18 months previously. We believe that symptom free patients who receive nucleoside-analogue therapy should have hepatic function constantly monitored, especially those with past or present lactic acidaemia.

Acute Disease↗
PubMed2001

Molecular diagnosis of infective endocarditis--a new Duke's criterion.

The molecular approach of PCR amplification of specific gene targets and universal loci for bacteria (16S rRNA) and fungi (18S, 28S and 5.8S rRNA) and subsequent sequencing was used to identify the possible causal microbial agent(s) in blood culture (47 patients) and heart valve material (30 patients) from patients with suspected infective endocarditis (IE). Culture and molecular results were analysed with respect to the patients' clinical background and the Duke Criteria. The findings demonstrated that: (i) all patients who were definite or possible cases were positive by PCR, even patients whose blood culture and valve material were culture-negative; and (ii) all patients who were rejected as having IE were also negative by PCR, with the exception of 1 patient who had bacteraemia from another source and 5 patients whose blood culture material was believed to contain an environmental contaminant. Direct molecular identification of the aetiological agents responsible for IE from blood culture material may enable specific treatment to commence at an earlier stage of the disease and hence reduce the need for valve replacement. Such a molecular approach may aid in the diagnosis of IE and should therefore be included as an additional major criterion in the Duke's classification scheme.

Bartonella↗
PubMed2000

Breath isoprene during acute respiratory exacerbation in cystic fibrosis.

Patients with cystic fibrosis (CF) experience a combination of chronic systemic oxidative stress, generation of free radicals in the lungs due to a hyperimmune response and a diminished ability to scavenge free radicals secondary to malabsorption and increased consumption. The authors asked the question, "Does breath isoprene content reflect systemic oxidative stress?" The study involved 12 CF patients and 12 matched healthy controls. The patients were sampled during acute respiratory exacerbation (increased respiratory symptoms, reduction in forced expiratory volume (FEV1) of >10%, and a decision to treat with intravenous antibiotics) and after two weeks of antibiotic treatment. Blood samples were examined for markers of oxidative stress. Breath samples were analysed for isoprene content. Malondialdehyde (MDA), erythrocyte membrane polyunsaturated fatty acids, protein sulphydryls and protein carbonyls all showed evidence of increased oxidative stress which was moderated by antibiotic treatment. Breath isoprene production rate was significantly lower in patients during exacerbation than in controls with a mean difference of-39 (95% confidence interval (CI) -11-57) pmol.min.kg(-1) and increased to normal values following treatment (mean change 63 (95% CI 42-84) pmol.min.kg(-1)). In conclusion, breath isoprene cannot be considered a reliable marker of oxidative stress.

Adult↗
PubMed1999

Oxidative stress during acute respiratory exacerbations in cystic fibrosis.

BACKGROUND: Patients with cystic fibrosis experience chronic systemic oxidative stress. This is coupled with chronic inflammation of the lung involving bronchial polymorphonuclear neutrophil accumulation and activation. We hypothesised that, during periods of acute respiratory exacerbation, free radical activity and consequent damage would be most marked and that intensive treatment of the infection would result in improvement towards values found during stable periods. METHODS: Plasma and red blood cells were collected from 12 healthy normal volunteers and from 12 patients with cystic fibrosis with an acute respiratory exacerbation (increased respiratory symptoms, reduction in forced expiratory volume in one second (FEV1) of more than 10%, and a decision to treat with intravenous antibiotics). Further samples were collected from patients following two weeks of treatment. Samples were analysed for inflammatory markers, markers of free radical damage, and aqueous and lipid phase scavengers. RESULTS: During respiratory exacerbations FEV1 and forced vital capacity (FVC) were lower than in controls (mean differences -2.82 (95% CI -2.12 to -3.52) and -3. 79 (-3.03 to -4.55) l, respectively) but improved following treatment (mean change 0.29 (95% CI 0.18 to 0.40) and 0.33 (0.23 to 0.43) l, respectively). Inflammatory markers during exacerbations were significantly higher in patients than in controls with the following mean (95% CI) differences: C reactive protein (CRP), 46 (17 to 75) g/l; neutrophil elastase alpha1-antiprotease complexes (NEAPC), 4.4 (1.77 to 7.07) mg/l; white cell count (WCC), 5.3 (4.7 to 5.9) x 10(9)/l. These markers decreased significantly following treatment with the following mean (95% CI) changes: CRP -26 (-10 to -42) g/l; NEAPC -3.1 (-1.3 to -4.9) mg/l; WCC -1.5 (-1.3 to -1.7) x 10(9)/l. Malondialdehyde (MDA) as a marker of free radical activity was significantly higher in patients during exacerbations than in controls with a mean (95% CI) difference of 193 (107 to 279) which improved with treatment (mean change -56 (95% CI -28 to -84) nmol/mmol cholesterol). Red blood cell polyunsaturated fatty acids were significantly lower in patients than in controls with a mean difference of -4.4(95% CI -2.6 to -6.2) moles percent, but did not improve significantly after treatment. Protein carbonyls during exacerbations were not different from controls but did increase with treatment compared with levels during the exacerbation (mean change 0.39 (95% CI 0.11 to 0.67) micromol/g protein). Aqueous and lipid phase scavengers in patients during exacerbations were significantly lower than in controls with the following mean (95% CI) differences: ascorbate, -19.0 (-2.7 to -35.3) micromol/l; sulphydryls, -122 (-77 to -167) micromol/l; retinol, -237 (-47 to -427) nmol/mmol cholesterol; beta-carotene, -52.8 (-11.8 to -93.8) nmol/mmol cholesterol; luteine, -50.4 (-10.4 to -90.4) nmol/mmol cholesterol; lycopene, -90.1 (-30.1 to -150.1) nmol/mmol cholesterol. Treatment resulted in improvement with the following mean (95% CI) changes: sulphydryls, 50 (32 to 68) micromol/l; retinol, 152 (47 to 257) nmol/mmol cholesterol; alpha- and beta-carotene, 0.6 (0.0 to 1.2) and 7.6 (0.0 to 15.2) nmol/mmol cholesterol, respectively; alpha-tocopherol, 839 (283 to 1405) nmol/mmol cholesterol; and lycopene, 8.2 (0.0 to 16.2) nmol/mmol cholesterol. CONCLUSIONS: Abnormalities of markers of inflammation, free radical activity, and radical scavengers were significantly more extreme during acute respiratory exacerbations and showed improvement with treatment. The need to provide protection from inflammation and free radical damage should therefore be dynamic and related to the inflammatory and oxidative processes.

Acute Disease↗
PubMed1990

Managing for total quality in a large laboratory. Some examples.

A large laboratory, processing more than 30,000 requisitions every 24 hours, provides a unique opportunity to document the value of selected approaches to managing for total quality. Proficiency test errors are an important subset of this database. They can provide a quality control manager with essential diagnostic information if data are analyzed in a systematic fashion. There is no benefit to performing proficiency tests in duplicate or in handling them in a manner different from patients. In fact, error rates can be higher when proficiency tests are handled in a special manner. Finally, error is decreased when technologists receive real-time feedback on how well the process is performing.

Educational Measurement↗
PubMed1983

Normalization of the dexamethasone suppression test at discharge from hospital. Its prognostic value.

Fourteen patients with RDC diagnosis of primary, endogenous, major depressive disorder were studied in an inpatient setting. All were non-suppressors on the Dexamethasone Suppression Test on admission to hospital and were retested at discharge. Over 70% of patients continued to be non-suppressors at discharge, when in clinical remission. Four out of 14 patients converted to normal suppression. All 10 of the non-normalizers did poorly on follow-up: 3 patients committed suicide. All normalizers did well. Non-normalization of the DST at discharge from hospitalization may be more common than previously suspected and predicts poor clinical outcome.

Adult↗