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J McCall

Publications and source records attributed to J McCall.

At least 19 recordsLinked to original sources
PubMed2002

Rapid response and strict control measures can contain a hospital outbreak of Norwalk-like virus.

Norwalk-like viruses (NLVs) are a major cause of sporadic gastroenteritis in the community and of large outbreaks of gastroenteritis in hospitals and other institutions. In January 2001, 38 staff and 20 patients on an acute elderly care ward became ill in an outbreak of gastrointestinal infection. Using reverse transcription polymerase chain reaction (RT-PCR) the causative agent was identified as NLV. No link was found between particular foods eaten and illness. At various times in the course of the outbreak a number of wards were implicated, but in hindsight the outbreak was confined to one ward. A prompt and rigorous response was successful in containing the spread of NLV infection to just one ward and stopping it in a few days.

Caliciviridae Infections↗
PubMed2001

Liver resections in Auckland 1998-2001: mortality, morbidity and blood product use.

AIMS: There has been a marked increase in the number of liver resections undertaken at Auckland Hospital since 1998. Low central venous pressure anaesthesia was routinely used for liver resection during this period. The aim of this study was to review this experience, with particular emphasis on the peri-operative outcomes of morbidity, mortality and blood product use. METHODS: All patients undergoing liver resection from January 1998 to May 2001 were included in the review. Standardised data were collated retrospectively from hospital records and transferred to an electronic database for analysis. RESULTS: Of 123 patients undergoing liver resection, 113 were elctive and ten were urgent operations. 65% had major resections and 10% had synchronous extrahepatic surgery. There were three post-operative deaths (mortality 2.4%) due to liver failure and sepsis. One or more complications occurred in 68 patients (morbidity 55%). 72% did not receive a blood transfusion during their hospital stay. Only two of 113 elective patients required a massive blood transfusion (ten or more units). CONCLUSIONS: Mortality in the study period was low but morbidity remains significant. Blood product use was low in elective patients. These results compare well with those of specialised hepatobiliary units internationally.

Adolescent↗
PubMed2001

Electrochemiluminescence of copper(I) bis(2,9-dimethyl-1,10- phenanthroline).

The electrochemical and electrochemiluminescence (ECL) properties of Cu[dmp]2+ (dmp = 2,9-dimethyl-1,10-phenanthroline) have been investigated. ECL has been observed for Cu(dmp)2+ in aqueous, nonaqueous, and mixed solvent solutions using tri-n-propylamine as an oxidative-reductive coreactant. The ECL intensity peaks at potential corresponding to oxidation of both the coreactant and Cu(dmp)2+. The peak potential corresponding to maximum ECL emission is approximately 500 mV more anodic than corresponding oxidative peak potentials, indicating that the ECL emission may be due to the formation of either the *Cu(dmp)2+ metal-to-ligand charge-transfer excited state or an excited-state product of Cu(dmp)2+ oxidation. ECL efficiencies (phiecl = photons generated per redox event) are solvent-dependent (phiecl (CH3CN) > phiecl (50:50 (v/v) CH3CN:H20) > phiecl (H2O)) and correspond fairly well with photoluminescence efficiencies. Increased ECL efficiencies (> or = 50-fold) are observed in the presence of the nonionic surfactant Triton X-100.

Copper↗
PubMed2001

Two controlled trials of antibiotic treatment in patients with persistent symptoms and a history of Lyme disease.

BACKGROUND: It is controversial whether prolonged antibiotic treatment is effective for patients in whom symptoms persist after the recommended antibiotic treatment for acute Lyme disease. METHODS: We conducted two randomized trials: one in 78 patients who were seropositive for IgG antibodies to Borrelia burgdorferi at the time of enrollment and the other in 51 patients who were seronegative. The patients received either intravenous ceftriaxone, 2 g daily for 30 days, followed by oral doxycycline, 200 mg daily for 60 days, or matching intravenous and oral placebos. Each patient had well-documented, previously treated Lyme disease but had persistent musculoskeletal pain, neurocognitive symptoms, or dysesthesia, often associated with fatigue. The primary outcome measures were improvement on the physical- and mental-health-component summary scales of the Medical Outcomes Study 36-item Short-Form General Health Survey (SF-36)--a scale measuring the health-related quality of life--on day 180 of the study. RESULTS: After a planned interim analysis, the data and safety monitoring board recommended that the studies be discontinued because data from the first 107 patients indicated that it was highly unlikely that a significant difference in treatment efficacy between the groups would be observed with the planned full enrollment of 260 patients. Base-line assessments documented severe impairment in the patients' health-related quality of life. In intention-to-treat analyses, there were no significant differences in the outcomes with prolonged antibiotic treatment as compared with placebo. Among the seropositive patients who were treated with antibiotics, there was improvement in the score on the physical-component summary scale of the SF-36, the mental-component summary scale, or both in 37 percent, no change in 29 percent, and worsening in 34 percent; among seropositive patients receiving placebo, there was improvement in 40 percent, no change in 26 percent, and worsening in 34 percent (P=0.96 for the comparison between treatment groups). The results were similar for the seronegative patients. CONCLUSIONS: There is considerable impairment of health-related quality of life among patients with persistent symptoms despite previous antibiotic treatment for acute Lyme disease. However, in these two trials, treatment with intravenous and oral antibiotics for 90 days did not improve symptoms more than placebo.

Administration, Oral↗
PubMed2001

Pediatric minor head trauma: indications for computed tomographic scanning revisited.

BACKGROUND: Although the use of computed tomographic (CT) scanning in severe head trauma is an accepted practice, the indications for its use in minor injury remain ill defined and subjective. We sought to define the incidence and identify risk factors for intracranial injury (ICI) after minor head trauma in children who did not have suspicious neurologic symptoms in the field or on presentation. METHODS: From January 1, 1992, until April 1, 2000, 569 blunt trauma patients (age < 16 years) with a Glasgow Coma Scale score of 14 or 15 triaged by American College of Surgeons Pediatric Mechanism Criteria at a Level I trauma center received head CT scan. Loss of consciousness (LOC) status was known for 429. This subgroup was retrospectively reviewed for mechanism, age, Injury Severity Score, LOC status, GCS score, associated injuries, and CT scan findings (normal, fracture only, or intracranial injury). Relative risk values for intracranial injury were generated and statistical significance was assessed. RESULTS: Fourteen percent (62 of 429) of study patients (GCS score of 14 and 15) had ICI. Sixteen percent of patients (35 of 215) with GCS score of 15 and (-)LOC (negative for LOC) had intracranial injury manifesting as subdural hematoma, epidural hematoma, subarachnoid hemorrhage, or brain contusion. Three required surgery for intracranial mass lesions. One patient deteriorated and required intubation and intensive care unit management. Neither (+)LOC (positive for LOC) nor GCS score of 14 increased the likelihood of intracranial injury over those patients without loss of consciousness or with GCS score of 15. Distant injury was also not an independent predictor of ICI for those with GCS scores of 14 or 15, as 84% of the ICI group had head injury only. Skull fracture was a risk factor for ICI but had poor negative predictive value, as 45% of patients with ICI did not have fractures. Similarly, minor craniofacial soft tissue trauma was a significant risk factor (relative risk, 11) that had marginal negative predictive value (0.95), as 14% (9 of 62) of ICI patients did not have superficial craniofacial injury. CONCLUSION: A normal neurologic exam and maintenance of consciousness does not preclude significant rates of intracranial injury in pediatric trauma patients. Contrary to convention, neither LOC nor mild altered mentation is a sensitive indicator with which to select patients for CT scanning. Skull fractures and superficial craniofacial injury are similarly unreliable. Identification of these patients is important for the occasional case requiring intervention and for the tracking of complications. A liberal policy of CT scanning is warranted for pediatric patients with a high-risk mechanism of injury despite maintenance of normal neurologic status in the field and at hospital screening.

Adolescent↗
PubMed2001

Delayed diagnosis in pediatric blunt trauma.

OBJECTIVE: Identification of injuries of a traumatized patient is a mandate for the emergency department (ED) and the trauma team. Delayed diagnosis of injury in trauma patients leads to increased morbidity, mortality, dissatisfaction, and risk of litigation. Comparing children admitted for blunt trauma, with and without delay, this study examines risk factors for delayed diagnosis. METHODS: Delays in diagnosis from 1991 to 1996 were identified during prospective collection of trauma registry data. Controls were randomly selected from the trauma registry. Charts from both groups were retrospectively reviewed. RESULTS: Fifty-eight patients had 65 delays in diagnosis. Significant independent delay variables included: female, motor vehicle crash (MVC)-related mechanism, altered consciousness, higher injury severity score, and multiple injuries (P < 0.05). Trauma team activation, documentation of tertiary survey, and length of hospitalization were greater in patients with delay injuries (P < 0.05). Logistic regression identified MVC-related mechanism, female, facial, and extremity injuries as a combination of predictors. CONCLUSIONS: Delays occurred in 1% of patients. Trauma team care itself did not protect all patients from delay. Injury severity at presentation alone is not an adequate predictor of delayed diagnosis in the pediatric patient. A combination of variables was identified as negative predictors of delay. Further study is needed to validate these criteria, and determine if earlier diagnosis would effect quality.

Academic Medical Centers↗
PubMed2001

Co-stimulatory blockade and tolerance induction in transplantation.

Recipients of organ and tissue transplants require lifelong immunosuppression to prevent rejection. Better understanding of the processes culminating in allograft rejection has led to novel approaches to modulating the immune response. Co-stimulatory signals between antigen-presenting and -responding cells are essential for a normal alloimmune response, and blockade of these pathways during initial graft-host interaction may be used to ameliorate or prevent a destructive response from proceeding. A large number of experimental studies now support this concept, and early clinical trials have been initiated. Despite some early difficulties and many unanswered questions, co-stimulatory blockade has major potential as a future immune-modulating mechanism for use in clinical transplantation.

Animals↗
PubMed2000

The kinetics of CD154 (CD40L) expression in peripheral blood mononuclear cells of healthy subjects in liver allograft recipients and X-linked hyper-IgM syndrome.

UNLABELLED: The costimulatory pathways play a key role in T cell activation during allograft rejection (AR). Inhibition of the T cell costimulatory molecule CD154 (CD40 ligand) has been effective in producing long-term allograft survival in rodents and non-human primates. The role of the CD40-CD154 pathway in human orthotopic liver transplantation (OLT) has not been examined. AIM: To describe the patterns of CD154, CD69 and CD152 (CTLA4) expression in OLT recipients and to determine their temporal relationship to AR. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from 15 OLT allograft recipients just prior to and for seven consecutive days postoperatively. Gene and protein expression of CD154, CD69 and CD154 were examined by reverse transcription-polymerase chain reaction (RT-PCR) and flow cytometry (FC), respectively. RESULTS: FC failed to demonstrate an up-regulation of CD154 and CD152 protein expression during the first postoperative week. Intracellular FC did not increase the sensitivity. There was an increased level of CD3+ CD8+ T cells expressing CD69 at the time of rejection compared to that on day 0. RT-PCR demonstrated a sporadic expression of CD154 and CD69 mRNA, with no correlation to episodes of acute cellular rejection. In vitro stimulation of PBMCs revealed an impaired up-regulation of CD154 in patients receiving conventional immunosuppression compared to healthy controls. The assays were validated using positive and negative controls, including a family with X-linked hyper-IgM syndrome. CONCLUSION: We found no evidence of spontaneous CD154 gene or protein expression in PBMCs associated with acute rejection episodes following OLT. Immunosuppression resulted in impaired responses to ex vivo stimulation. Lymphocyte costimulatory pathways play a critical role in mediating acute allograft rejection. However, we found no evidence of spontaneous CD154 gene or protein expression in PBMCs associated with acute rejection episodes following OLT. Furthermore, stimulation in vitro resulted in less up-regulation of CD154 than for healthy controls.

Abatacept↗
PubMed2000

Fibroid embolisation: a technique not without significant complications.

Uterine artery embolisation is a new minimally invasive technique used for the treatment of fibroids. Twenty-one women underwent bilateral uterine artery embolisation at our unit, and we assessed the efficacy, morbidity and patient satisfaction with the procedure. Mixed outcomes were found. Reduction in fibroid volume measured by magnetic resonance imaging was impressive, and the majority of women felt their symptoms had improved. One woman achieved a full term pregnancy following the procedure. However, the procedure involved a significant inpatient stay, analgesia requirement, and a slower recovery time than anticipated. One woman died following overwhelming sepsis occurring 10 days after the procedure. Further studies are required to assess the role this technique may play in the management of uterine fibroids.

Adult↗
PubMed1999

Determinaton of two major metabolites of the novel anti-tumour agent 5,6-dimethylxanthenone-4-acetic acid in hepatic microsomal incubations by high-performance liquid chromatography with fluorescence detection.

High-performance liquid chromatographic methods have been developed and validated for the glucuronidated and oxidative metabolites of the novel anti-tumour agent 5,6-dimethylxanthenone-4-acetic acid (DMXAA), produced in human liver microsomal incubations. Calibration curves for DMXAA acyl glucuronide (DMXAA-Glu) and 6-hydroxymethyl-5-methylxanthenone-4-acetic acid (6-OH-MXAA) were constructed over the concentration ranges of 0.25 to 20 and 0.5 to 40 microM, respectively. Assay performance was determined by intra- and inter-day accuracy and precision of quality control (QC) samples. The difference between the theoretical and measured concentration, and the coefficient of variation, were less than 15% at low QC concentrations, and less than 10% at medium and high QC concentrations for both analytes. The methods presented good accuracy, precision and sensitivity for use in kinetic studies of the glucuronidated and oxidative metabolites of DMXAA in human liver microsomes.

Antineoplastic Agents↗
PubMed1999

Perceived and physiological indicators of relaxation: as different as Mozart and Alice in chains.

The effects of listening to different types of music on perceived and physiological indicators of relaxation were evaluated. Fifty-six undergraduate students, 24 males and 32 females, mean age of 21, were randomly assigned to listen to classical, hard rock, self-selected relaxing music, or no music. Participants' relaxation level, skin temperature, muscle tension and heart rate were evaluated before and after exposure to a music condition. Analyses of variance using baseline measures as covariates indicated that skin temperature decreased for all conditions (p = 0.001) and the classical, self-selected relaxing music and no music groups reported significant increases in feelings of relaxation (p = 0.004). These results partially support the hypothesis that classical and self-selected relaxing music can increase perceptions of relaxation to a greater degree than listening to hard rock music. However, no differences were found between different types of music on physiological indicators of arousal. Implications for using music to reduce stress were discussed.

Adult↗
PubMed1999

Embolization of uterine fibroids.

14 patients have undergone uterine artery embolization of uterine fibroids. No complications related to the procedure have occurred. In all six of the cases with available data, there has been a reduction in fibroid volume as measured with MRI at 2 months post procedure (average reduction 43%). Technical aspects of this promising procedure are described.

Adult↗