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M Jones

Publications and source records attributed to M Jones.

At least 163 records · Page 9Linked to original sources

Integrating clinical reasoning and evidence-based practice.

Evidence-based practice involves basing clinical decisions and practice on the best available evidence. What do nurses need to think about when seeking to pursue evidence-based practice? What challenges do practitioners face in blending clinical reasoning with evidence-based practice? In this article, the authors argue against basing clinical practice on narrow definitions of evidence, relying solely on experimental findings or, even more exclusively, on randomized controlled trials. Instead of defining best practice narrowly by the strength of the current empirical evidence used to guide clinical decisions, it should be defined broadly by what is the best information to use to make decisions for a given patient in a particular setting. Credible and accountable clinical decisions rely on a number of forms of knowledge and evidence. This evidence includes findings from across the range of research methods, including experimental, interpretive, and action research. In nursing, it also includes evidence that has arisen from the depth of practice knowledge of expert clinical nurses. Professionals, particularly advanced and expert clinicians such as critical care nurses, use clinical reasoning to guide their practice in the uncertainty of clinical practice contexts. This reasoning helps the nurse make judgments about the relevance of particular research and clinical evidence for a specific patient and setting.

Decision Making↗

Application of monitoring data for Giardia and Cryptosporidium to boil water advisories.

Despite the problems associated with analyzing water samples for Giardia cysts and Cryptosporidium oocysts, the data can be very useful if their strengths and weaknesses are understood. Two municipalities in northern Ontario, Temagami and Thunder Bay, both issued boil water advisories for Giardia contamination. Data from these two cities are compared to show that only one municipality experienced a real outbreak, whereas the other did not. The concentration of Giardia cysts was much higher than background during the outbreak at Temagami, and the postoutbreak concentrations of cysts were very similar to the long-term average cyst concentration at Thunder Bay. The waterborne outbreak of giardiasis at Temagami was characterized by consistent positive results from water samples, concentrations two to three orders of magnitude higher than normal, and an obvious increase in the number of cases of giardiasis in the population. No outbreak was experienced at Thunder Bay, but a boil water advisory (BWA) was set in place for more than a year on the basis of a single sample from Loch Lomond in which only two cysts were detected but the sample equivalent volume was low. This gave the impression of a sudden increase in concentration, but 39 of 41 subsequent samples were negative. Additional factors that led to a BWA at Thunder Bay are described, and recommendations are presented to help determine when a BWA is necessary and when it should be rescinded.

Animals↗

Impact of chronic gastrointestinal symptoms in diabetes mellitus on health-related quality of life.

OBJECTIVES: Morbidity from GI symptoms in diabetes is considered to be high, but no studies have quantified the impact of GI symptoms in diabetes on health-related quality of life. We hypothesized that diabetics reporting increased GI symptoms would experience more impaired quality of life. METHODS: Subjects from the community with diabetes (n = 892) and outpatients with diabetes (n = 209) were recruited for this study. Subjects were divided into type 1 (diabetes diagnosed at age <30 yr and requiring insulin) and type 2. A validated questionnaire measuring GI symptoms and diabetes status and the Short Form-36 were completed. The results were compared with Australian normal data. GI symptom groups measured were frequent abdominal pain, bowel-related abdominal pain, reflux, dyspepsia, constipation, diarrhea, and fecal incontinence. RESULTS: There was a clinically significant decrease in quality-of-life scores in diabetics compared with population norms across all subscales. The impact on quality of life in diabetes was predominantly observed in type 2 diabetics. The quality-of-life scores in all subscales decreased markedly with increasing numbers of distinct GI symptom groups, and this was similar in community and outpatient diabetics. For all the Short Form-36 subscales, GI symptom groups were significantly (all p < 0.0001) associated with poorer quality of life in diabetes, independent of age, gender, smoking, alcohol use, and type of diabetes. CONCLUSIONS: GI symptoms impact negatively on health-related quality of life in diabetes mellitus.

Adult↗

Psychological distress is linked to gastrointestinal symptoms in diabetes mellitus.

OBJECTIVE: Gastrointestinal (GI) symptoms are common in patients with long-standing diabetes mellitus, but the pathogenesis is controversial. We aimed to determine if GI symptoms are linked to psychological distress in diabetes. METHODS: A consecutive sample of outpatients with diabetes mellitus (n = 209) and a random sample of community diabetics (n = 892) completed a validated questionnaire measuring GI symptoms, the Hospital Anxiety and Depression (HAD) Scale for anxiety and depression, and the Eysenck short neuroticism scale. RESULTS: Overall, 42% reported one or more GI symptoms: bloating, abdominal pain, loose stools, and urgency were most common. The mean HAD and neuroticism scores were significantly higher for most GI symptoms (11 of 14, all p < 0.05), and a dose-response relationship was observed. GI symptoms were, in general, approximately twice as frequent in cases with anxiety or depression (HAD > or = 11). Anxiety, depression, and neuroticism were each independently associated with the number of GI symptoms, adjusting for age, gender, duration and type of diabetes, and self-reported glycemic control. CONCLUSIONS: Increased levels of state anxiety and depression and neuroticism are associated with upper and lower GI symptoms in diabetes mellitus. It is uncertain whether psychological distress is causally linked to symptoms, or whether GI symptoms per se increase levels of anxiety and depression.

Anxiety↗

Can symptoms discriminate among those with delayed or normal gastric emptying in dysmotility-like dyspepsia?

OBJECTIVE: Different subgroups can be identified in functional dyspepsia based on symptom type or severity, and may correlate with pathophysiological disturbances. In particular, female sex and severe fullness and vomiting have been reported to be strong independent predictors of slow solid gastric emptying. We aimed to determine if symptom patterns or severity could identify those with abnormal gastric emptying among patients with dysmotility-like functional dyspepsia and, for comparison, type I diabetes mellitus. METHODS: Patients with postprandial symptoms and documented functional dyspepsia by endoscopy (n = 551) and patients with type I diabetes who had postprandial dyspepsia (n = 247) enrolling in two separate randomized controlled trials were evaluated at baseline. Patients were assigned to either the delayed or normal gastric emptying strata, based on a validated C13 octanoic acid breath test with sampling over 4 h. A self-report questionnaire measured the presence and severity of eight symptoms on visual analog scales. The validated Nepean Dyspepsia Index measured the frequency, severity, and bothersomeness of 15 upper GI symptoms on Likert scales. RESULTS: Gastric emptying was definitely delayed (t1/2 > 192 min) in 24% of patients with functional dyspepsia and 28% with diabetes. Delayed gastric emptying was associated with female gender but not age or Helicobacter pylori status. The age- and sex-adjusted risk (odds ratio) of delayed gastric emptying for the upper GI symptoms ranged from 0.99 to 1.0 (all p values > or =0.2). The results were very similar in functional dyspepsia and diabetes. There was also no correlation between t1/2 and number of symptoms or symptom severity scores. CONCLUSIONS: Symptom prevalence and severity were similar in dyspeptic patients with and without delayed gastric emptying. Specific symptoms do not seem to be of predictive value in dysmotility-like dyspepsia for identifying alterations of gastric emptying.

Adult↗

Marrow-derived CD40-positive cells are required for mice to clear Cryptosporidium parvum infection.

To clear a Cryptosporidium parvum infection, mice need CD4+ T cells, major histocompatibility complex class II, and an intact CD40-CD154 signaling pathway. CD40 is constitutively expressed on marrow-derived cells such as dendritic cells and B lymphocytes and is induced by gamma interferon (IFN-gamma) on most somatic cells. To determine whether the CD40 needed to clear a C. parvum infection has to be on marrow-derived mononuclear cells or on the epithelial cells that normally harbor the parasite, we transplanted CD40-/- mice with CD40+/- bone marrow and then infected them with C. parvum. These chimeras cleared the C. parvum infection, while CD40+/- controls transplanted with CD40-/- marrow cells remained infected. CD40 expression on marrow-derived cells therefore suffices for a C. parvum infection to be cleared, while CD40 expression on intestinal epithelial cells is not sufficient. There was no difference between the acquisition of CD69 and CD154 by mesenteric lymph node T cells of C. parvum-infected animals with intact or disrupted CD40-CD154 pathways. CD4 T cells entered the intestinal laminae propriae of C. parvum-infected animals whether or not the CD40 genes of these recipients were intact. These results suggest that, for a C. parvum infection to be cleared, CD40 is not necessary for T-cell activation but may instead contribute to an effector pathway of marrow-derived cells.

Adoptive Transfer↗

Epstein-Barr virus LMP-1 natural sequence variants differ in their potential to activate cellular signaling pathways.

The latent membrane protein 1 (LMP-1) oncogene of Epstein-Barr virus (EBV) is believed to contribute to the development of many EBV-associated tumors, and there is evidence that sequence variation can affect some functions of LMP-1. Most studies have been restricted to the prototype B95.8 LMP-1 gene and genes isolated from EBV of nasopharyngeal carcinoma (NPC) patients. Here, we analyzed the signaling functions of LMP-1 from a panel of nine EBV isolates, including representatives of four defined groups of European LMP-1 variants (groups A to D [K. Sandvej, J. W. Gratama, M. Munch, X. G. Zhou, R. L. Bolhuis, B. S. Andresen, N. Gregersen, and S. Hamilton-Dutoit, Blood 90:323-330, 1997]) and Chinese NPC-derived LMP-1. Chinese and group D variants activated the transcription factor NF-kappa B two- to threefold more efficiently than B95.8 LMP-1, while Chinese, group B, and group D variants similarly activated activator protein 1 (AP-1) transcription more efficiently than did B95.8 LMP-1. However, there were no amino acid substitutions in the core binding regions for tumor necrosis factor receptor-associated adapter proteins known to mediate NF-kappa B and AP-1 activation. In contrast, despite sequence variation in the proposed Janus kinase 3 binding region, STAT activation was remarkably constant among the panel of LMP-1 variants. Analysis of the induction of CD54 (intercellular adhesion molecule 1) protein expression by the LMP-1 variants showed differences that did not correlate with either NF-kappa B or AP-1. Therefore, while the defined sequence variant groups do correlate with LMP-1 function, the results highlight the fact that the relationship between sequence variation and signaling function is extremely complex. It appears unlikely that one particular amino acid substitution or deletion will define a disease-associated variant of LMP-1.

Amino Acid Sequence↗

Effect of intragenic rearrangement and changes in the 3' consensus sequence on NSP1 expression and rotavirus replication.

The nonpolyadenylated mRNAs of rotavirus are templates for the synthesis of protein and the segmented double-stranded RNA (dsRNA) genome. During serial passage of simian SA11 rotaviruses in cell culture, two variants emerged with gene 5 dsRNAs containing large (1.1 and 0.5 kb) sequence duplications within the open reading frame (ORF) for NSP1. Due to the sequence rearrangements, both variants encoded only C-truncated forms of NSP1. Comparison of these and other variants encoding defective NSP1 with their corresponding wild-type viruses indicated that the inability to encode authentic NSP1 results in a small-plaque phenotype. Thus, although nonessential, NSP1 probably plays an active role in rotavirus replication in cell culture. In determining the sequences of the gene 5 dsRNAs of the SA11 variants and wild-type viruses, it was unexpectedly found that their 3' termini ended with 5'-UGAACC-3' instead of the 3' consensus sequence 5'-UGACC-3', which is present on the mRNAs of nearly all other group A rotaviruses. Cell-free assays indicated that the A insertion into the 3' consensus sequence interfered with its ability to promote dsRNA synthesis and to function as a translation enhancer. The results provide evidence that the 3' consensus sequence of the gene 5 dsRNAs of SA11 rotaviruses has undergone a mutation causing it to operate suboptimally in RNA replication and in the expression of NSP1 during the virus life cycle. Indeed, just as rotavirus variants which encode defective NSP1 appear to have a selective advantage over those encoding wild-type NSP1 in cell culture, it may be that the atypical 3' end of SA11 gene 5 has been selected for because it promotes the expression of lower levels of NSP1 than the 3' consensus sequence.

Amino Acid Sequence↗

Sensitisation to natural rubber latex: an epidemiological study of workers exposed during tapping and glove manufacture in Thailand.

OBJECTIVES: To estimate the prevalence of sensitisation to natural rubber latex in latex tappers and latex glove factory workers, and to relate this to airborne exposure to latex. METHODS: Five hundred workers employed in three latex glove factories, 314 tappers, and 144 college students (control group) were studied. The workers in the glove factories were classified into three exposure groups; high, moderate, and low. Personal exposures to natural rubber latex aeroallergens were measured by immunoassay. Symptom questionnaires and skin prick tests with latex allergens (Stallergènes 1:200 w/v) and other common environmental allergens were performed. The criterion for positivity was a wheal reaction at least 3 mm in diameter greater than that to a diluent control. RESULTS: The geometric mean (GM) concentration of latex in air was 15.4 microg/m(3) for those employed in glove stripping, glove inspections, and packing of powdered gloves. The moderate exposure glove manufacturing group and the tappers had GM concentrations of 2.3 and 2.4 microg/m(3) respectively, compared with United Kingdom users of latex powdered gloves,who had GM concentrations of 0.5 microg/m(3). The prevalence of sensitisation to latex in the tappers and latex glove factory workers was 1.3% and 1.7% respectively. No positive cases were found among the college students. Workers who showed a positive skin prick test to latex were more likely to be atopic. Work related respiratory and dermatological symptoms were found in about 20% of each population studied, but were not related to the presence of positive latex prick tests. CONCLUSIONS: This study suggests that in the Thai latex industries, latex sensitisation is rare despite high concentrations of airborne exposure and is less prevalent than in the healthcare sector in Europe where skin exposure is greater.

Adult↗

Report of occupational asthma due to phytase and beta-glucanase.

OBJECTIVES: Occupational asthma is the principal cause of respiratory disease in the workplace. The enzymes phytase and beta-glucanase are used in the agricultural industry to optimise the nutritional value of animal feeds. A relation between these enzymes and occupational asthma in a 43 year old man was suspected. METHODS: Inhalation challenge tests were performed with the enzymes phytase, beta-glucanase, and amylase. Skin prick tests were performed with the enzymes diluted to a concentration of 1 mg/ml and 5 mg/ml. Specific IgE to phytase and beta-glucanase were measured with a radioallergosorbent test. RESULTS: Baseline spirometry values were normal. A histamine challenge test showed bronchial hyperreactivity. Exposure to phytase and beta-glucanase led to significant reductions in forced vital capacity and forced expired volume in 1 second. No significant differences were noted after exposure to amylase. Skin tests showed a positive reaction to beta-glucanase (5 mm) at a concentration of 1 mg/ml and positive reactions to beta-glucanase (7 mm) and phytase (5 mm) at a concentration of 5 mg/ml. Similarly specific IgE was present against both phytase and beta-glucanase, at 2.5% and 9.3% binding respectively (2% binding is considered positive). CONCLUSIONS: This is the first description of occupational asthma due to the enzymes phytase and beta-glucanase. Their addition to the ever increasing list of substances associated with occupational asthma will have notable implications for those exposed to these enzymes.

6-Phytase↗

Genes other than TLR4 are involved in the response to inhaled LPS.

For several decades, the mouse strains C3H/HeJ and C57BL/10ScNCr have been known to be hyporesponsive to endotoxin or lipopolysaccharide (LPS). Recently, mutations in Toll-like receptor (TLR) 4 have been shown to underlie this aberrant response to LPS. To further determine the relationship between TLR4 and responsiveness to LPS, we genotyped 18 strains of mice for TLR4 and evaluated the physiological and biological responses of these strains to inhaled LPS. Of the 18 strains tested, 6 were wild type for TLR4 and 12 had mutations in TLR4. Of those strains with TLR4 mutations, nine had mutations in highly conserved residues. Among the strains wild type for TLR4, the inflammatory response in the airway induced by inhalation of LPS showed a phenotype ranging from very sensitive (DBA/2) to hyporesponsive (C57BL/6). A broad spectrum of airway hyperreactivity after inhalation of LPS was also observed among strains wild type for TLR4. Although the TLR4 mutant strains C3H/HeJ and C57BL/10ScNCr were phenotypically distinct from the other strains with mutations in the TLR4 gene, the other strains with mutations for TLR4 demonstrated a broad distribution in their physiological and biological responses to inhaled LPS. The results of our study indicate that although certain TLR4 mutations can be linked to a change in the LPS response phenotype, additional genes are clearly involved in determining the physiological and biological responses to inhaled LPS in mammals.

Animals↗

The current status of maggot therapy in wound healing.

The clinical use of sterile maggots under the brand name LarveE has increased steadily in the UK since they were introduced in the UK in late 1995. Some 50 articles have been published in the last 4 years that describe the cost-effectiveness of maggot therapy in a variety of wound types including leg ulcers, pressure ulcers and diabetic ulcers. The ability of these creatures to combat wound infection has been well documented including those caused by antibiotic-resistant strains of bacteria such as methicillin-resistant Staphylococcus aureus. No significant risks or adverse events have been linked to the use of maggots, although their presence may increase pain levels in leg ulcers associated with ischaemic disease.

Animals↗

Comparative practice patterns of emergency medicine physicians and pediatric emergency medicine physicians managing fever in young children.

BACKGROUND/OBJECTIVE: The management of fever in young children is a controversial topic. This study seeks to compare the management approaches between general emergency medicine physicians (GEMPs) and pediatric emergency medicine physicians (PEMPs) and correlate them to existing practice guidelines. DESIGN/METHODS: All charts of children age 3 to 36 months presenting with the complaint of fever at both a children's hospital emergency department (ED) and a general ED from June 1, 1998 to September 1, 1998; December 1, 1998 to April 1, 1999; and June 1, 1999 to September 1, 1999 were retrospectively reviewed. Fever was defined as >/=39 degrees C. Patients with a history of immunodeficiency, chronic illness, ventriculoperitoneal shunt, antibiotic use in the past 48 hours, or focal infection noted on examination were excluded. Data collected included focal exam findings, laboratory tests, diagnosis, treatment, and disposition. Variances from the practice guidelines were tabulated and compared. RESULTS: One thousand three hundred twenty-three eligible children met exclusion criteria and were seen by PEMPs; 755 were eliminated because of exclusion criteria (526 because of focal infection). Twenty-two (4%) of 568 remaining patients were admitted to the hospital. Two hundred twenty-eight eligible children were seen by GEMPs; 147 were excluded (109 because of focal infection). No patients were admitted to the hospital. PEMPs ordered more complete blood counts (324/568 vs 27/81), more blood cultures (321/568 vs 27/81), and more urine cultures (208/568 vs 20/81) than GEMPs. GEMPs ordered more chest radiographs and cerebrospinal fluid analyses than PEMPs; GEMPs ordered less complete blood counts, blood cultures, and urine cultures than PEMPs. GEMPs diagnosed more focal infections (109/228 vs 526/1323), and conflicted more often with the practice guidelines (66/79 vs 225/498) than PEMPs. Patients spent an average of 2.26 +/- 0.16 hours in the pediatric ED versus 3.0 hours +/- 0.18 hours in the general ED. CONCLUSIONS: Significant differences in the management of the young child with fever and no source exist between these two groups of physicians. These variations affect both cost and standard of care. Future studies assessing whether these strategies affect patient outcomes would further elucidate their clinical implication.

Bacterial Infections↗

Differential activation of p38 mitogen-activated protein kinase isoforms depending on signal strength.

We have investigated the ability of the mitogen-activated protein kinase (MAPK) kinase MKK6 to activate different members of the p38 subfamily of MAPKs and found that some MKK6 mutants can efficiently activate p38alpha but not p38gamma. In contrast, a constitutively active MKK6 mutant activated both p38 MAPK isoforms to similar extents. The same results were obtained upon co-expression in Xenopus oocytes and in vitro using either MKK6 immunoprecipitates from transfected cells or bacterially produced recombinant proteins. We also found that the preferential activation of p38alpha by MKK6 correlated with more efficient binding of MKK6 to p38alpha than to p38gamma. Furthermore, increasing concentrations of constitutively active MKK6 differentially activated either p38alpha alone (low MKK6 activity) or both p38alpha and p38gamma (high MKK6 activity), both in vitro and in injected oocytes. The determinants for selectivity are located at the carboxyl-terminal lobe of p38 MAPKs but do not correspond to the activation loop or common docking sequences. We also showed that different stimuli can induce different levels of endogenous MKK6 activity that correlate with differential activation of p38 MAPKs. Our results suggest that the level of MKK6 activity triggered by a given stimulus may determine the pattern of downstream p38 MAPK activation in the particular response.

Amino Acid Sequence↗

An outbreak of asthma in a modern detergent factory.

The striking decrease in the occurrence of protease-induced occupational asthma in the detergent Industry has been attributed to enzyme encapsulation. We report an outbreak of asthma, at least equal in size to those reported in the 1960s, in a modem European factory which has exclusively used encapsulated enzymes. A survey revealed that enzyme sensitisation and work-related respiratory symptoms were positively correlated with airborne enzyme exposure. We suggest that encapsulation alone is insufficient to prevent enzyme-Induced allergy and asthma.

Adolescent↗