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John J Kelly

Publications and source records attributed to John J Kelly.

At least 37 records · Page 2Linked to original sources
PubMed2005

Ganglion blockade does not prevent cortisol-induced hypertension in man.

1. The aim of the present study was to assess the effect of ganglion blockade on blood pressure in cortisol treated human subjects. 2. Four healthy male subjects were treated with cortisol 80 mg/day for a 5-day period. Ganglion blockade was achieved by intravenous trimethaphan. 3. Ganglion blockade did not significantly alter blood pressure in the pretreatment phase or on the last day of cortisol treatment. 4. Taken together with our previous observations that sympathetic activity is unaltered or reduced by cortisol, these results suggest that cortisol induced hypertension in humans is not a result of overactivity of the autonomic nervous system.

Autonomic Nervous System↗
PubMed2005

Should we quantify insulin resistance in patients with renal disease?

Cardiovascular disease is a major cause of morbidity and mortality in dialysis patients. Vascular disease develops before the initiation of dialysis, and it is now recognized that chronic kidney disease (CKD) is an independent risk factor for cardiovascular disease. Death from cardiovascular disease is a more common endpoint of CKD than progression to dialysis. There are multiple mechanisms that contribute to the increased vascular risk of CKD, one of which is the presence of insulin resistance (IR). CKD is characterised by many features of the metabolic syndrome, and features of IR are also observed in dialysis and transplant patients. IR may be quantified by several different methods. One such method is homeostatic model assessment (HOMA) technique, which derives a measurement of IR from fasting plasma glucose and insulin concentrations. The HOMA index has been demonstrated to be an independent predictor of survival in dialysis patients. CKD is characterised by a chronic inflammatory response and abnormalities in the production and regulation of adipose tissue derived proteins, which may contribute to the development of IR. There are a range of interventions including diet and exercise programmes or medications that may influence IR; however, the impact of these interventions in the context of CKD has not been systematically evaluated.

Cardiovascular Diseases↗
PubMed2005

Design of a questionnaire to measure trust in an emergency department.

OBJECTIVE: To develop a valid and reliable questionnaire for measuring patient trust in an emergency department (ED) that can be administered by phone, direct interview, or mail. METHODS: This was a survey conducted at a Level 1 urban trauma center with an annual census of 52,000 visits. Literature review, focus group discussions, and direct patient interviews identified potential items for pilot surveys. Fifteen ED nurses, residents, and faculty scored the items on a 1-10 scale, rephrasing or removing ambiguous items to ensure face and content validity. A telephone survey with responses recorded on a five-point Likert scale was conducted. Reliability and internal consistency of items were tested using SPSS software. Factor analyses were performed using principal components analysis and Varimax rotation with Eigen values set at 1.0. RESULTS: A total of 383 patients seen in the ED were surveyed. Using two pilot surveys, 18 of 42 potential items were extracted among five factors identified as important to the development of trust. Internal consistency for the final 18 items was calculated, and a Cronbach's alpha of 0.88 was obtained for all items. Test-retest reliability was calculated by telephoning 38 patients twice, two weeks apart, and correlation coefficients of >0.748 were obtained for all items. CONCLUSIONS: This questionnaire can be used for telephone or direct interview to survey patients' trust in EDs.

Factor Analysis, Statistical↗
PubMed2005

Nerve conduction studies of the lateral femoral cutaneous nerve. Implications in the diagnosis of meralgia paresthetica.

The diagnosis of meralgia paresthetica, while based on clinical suspicion, can be confirmed via electrophysiological testing. Previous testing of the sensory conduction of the lateral femoral cutaneous nerve placed the stimulating electrode one centimeter medial to the anterior superior iliac spine (ASIS). This position is both uncomfortable for the patient and difficult for the operator to perform. The following article suggests an alternate position for the stimulating electrode, four centimeters distal to the ASIS. Twenty subjects served as their own controls and both the old technique and the new technique were performed. Using the old technique, the response rate was 35% (7 out of 20 subjects). Using the new technique, the response rate was 90% (18 out of 20 subjects). These results indicate a significantly higher response rate when the only variable altered is the electrode placement. This simple change in technique requires no more effort, cost, or training on the part of the operator yet produces a much higher percentage of responses.

Adult↗
PubMed2005

Peripheral neuropathy: the importance of history and examination for correct diagnosis.

A 48-year-old woman presented to the emergency department with hematemesis and a 6-month history of unsteady gait and falls due to tripping. Because of a history of alcohol abuse, the initial diagnosis was upper gastrointestinal bleeding secondary to alcoholic gastritis or gastric ulcer, with the neuropathy likely due to alcoholism or chronic inflammatory demyelinating polyneuropathy. After further neurological examination and careful review of nerve conduction studies, however, an inherited neuropathy was suspected. Despite denial by the patient and her daughter of a family history of neuropathy, both had a pes cavus deformity with muscle atrophy and partial foot drop gait. Subsequent testing of the daughter revealed the same nerve conduction findings as the patient's. Genetic testing showed that both women had the myelin PMP22 repeat defect characteristic of Charcot-Marie-Tooth disease. Endoscopy revealed that the patient had Osler-Weber-Rendu disease, which accounted for the hematemesis.

Alcoholism↗
PubMed2004

Oral appliance therapy reduces blood pressure in obstructive sleep apnea: a randomized, controlled trial.

STUDY OBJECTIVE: To investigate the short-term effect (4 weeks) of oral appliance therapy for obstructive sleep apnea on blood pressure. DESIGN: Randomized, controlled, crossover trial. SETTING: Multidisciplinary sleep disorders clinic in a university teaching hospital. PATIENTS: Sixty-one patients diagnosed with obstructive sleep apnea on polysomnography (apnea hypopnea index > or = 10 per hour and at least 2 of the following symptoms--daytime sleepiness, snoring, witnessed apneas, fragmented sleep; age > 20 years; and minimum mandibular protrusion of 3 mm). INTERVENTION: A mandibular advancement splint (MAS) and control oral appliance for 4 weeks each. MEASUREMENTS AND RESULTS: Polysomnography and 24-hour ambulatory blood pressure monitoring were carried out at baseline and following each 4-week intervention period. Patients showed a 50% reduction in mean apnea hypopnea index with MAS compared with the control and a significant improvement in both minimum oxygen saturation and arousal index. There was a significant reduction with the MAS in mean (+/- SEM) 24-hour diastolic blood pressure (1.8 +/- 0.5 mmHg) compared with the control (P = .001) but not in 24-hour systolic blood pressure. Awake blood-pressure variables were reduced with the MAS by an estimated mean (+/- SEM) of 3.3 +/- 1.1 mmHg for systolic blood pressure (P = .003) and 3.4 +/- 0.9 mmHg for diastolic blood pressure (P < .0001). There was no significant difference in blood pressure measured asleep. CONCLUSION: Oral appliance therapy for obstructive sleep apnea over 4 weeks results in a reduction in blood pressure, similar to that reported with continuous positive airway pressure therapy.

Adult↗
PubMed2004

Obesity.

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Gastric Bypass↗
PubMed2004

Electron-conducting quantum-dot solids with ionic charge compensation.

Electron-conducting quantum-dot solids can be prepared on the basis of assemblies of colloidal insulating nanocrystals if electrons can be injected in the delocalized conduction orbitals. We discuss the energetics of electron injection in such an artificial solid consisting of weakly coupled quantum dots. We show that quantum confinement and electron electron repulsion determine the charging characteristics. The electron electron repulsion energy can be screened by three-dimensional charge compensation from trapped holes or positive inert ions inserted in the assembly. We present experimental results on the electron storage and long-range transport in assemblies of ZnO nanocrystals in which the electron charge is compensated by positive ions. The electron electron repulsion energy in assemblies permeated with an aqueous electrolyte solution is strongly screened. In contrast, the repulsion energy is about 100 meV in aprotic solvents; the repulsion energy strongly influences electron storage and the characteristics of long-range electron transport.

Journal Article↗
PubMed2004

Use of 16S rRNA, 23S rRNA, and gyrB gene sequence analysis to determine phylogenetic relationships of Bacillus cereus group microorganisms.

In order to determine if variations in rRNA sequence could be used for discrimination of the members of the Bacillus cereus group, we analyzed 183 16S rRNA and 74 23S rRNA sequences for all species in the B. cereus group. We also analyzed 30 gyrB sequences for B. cereus group strains with published 16S rRNA sequences. Our findings indicated that the three most common species of the B. cereus group, B. cereus, Bacillus thuringiensis, and Bacillus mycoides, were each heterogeneous in all three gene sequences, while all analyzed strains of Bacillus anthracis were found to be homogeneous. Based on analysis of 16S and 23S rRNA sequence variations, the microorganisms within the B. cereus group were divided into seven subgroups, Anthracis, Cereus A and B, Thuringiensis A and B, and Mycoides A and B, and these seven subgroups were further organized into two distinct clusters. This classification of the B. cereus group conflicts with current taxonomic groupings, which are based on phenotypic traits. The presence of B. cereus strains in six of the seven subgroups and the presence of B. thuringiensis strains in three of the subgroups do not support the proposed unification of B. cereus and B. thuringiensis into one species. Analysis of the available phenotypic data for the strains included in this study revealed phenotypic traits that may be characteristic of several of the subgroups. Finally, our results demonstrated that rRNA and gyrB sequences may be used for discriminating B. anthracis from other microorganisms in the B. cereus group.

Bacillus cereus↗
PubMed2004

The evaluation of peripheral neuropathy. Part I: clinical and laboratory evidence.

Diagnosing peripheral neuropathies continues to be a challenge. Many potential etiologies exist and must be evaluated for those patients in whom the underlying cause of the neuropathy is unclear. The clinician must determine the tests that are appropriate given the clinical and laboratory findings and the extent of investigation that is warranted before diagnosing the neuropathy as idiopathic. A practical diagnostic approach for the non-neuromuscular neurologist is presented as the first installment of a 3-part review on evaluating peripheral neuropathies.

Biopsy↗
PubMed2004

The evaluation of peripheral neuropathy. Part II: Identifying common clinical syndromes.

The first of this 3-part series on the diagnosis and management of peripheral neuropathy focused on the recognition of neuropathy and its clinical and laboratory characterization as essential to determining etiology. This approach allows for the construction of a differential diagnosis that can be narrowed by subsequent diagnostic testing. This installment, along with the final one, will focus on recognition and management of common neuropathies likely to be seen by the average practitioner. Neuropathies covered in this second part include diabetic, autoimmune and inflammatory, toxic, neuropathies associated with plasma cell dyscrasias, and paraneoplastic neuropathies.

Adult↗
PubMed2003

Long-range transport in an assembly of ZnO quantum dots: the effects of quantum confinement, Coulomb repulsion and structural disorder.

We have studied the storage and long-range transport of electrons in a porous assembly of weakly coupled ZnO quantum dots permeated with an aqueous and a propylene carbonate electrolyte solution. The number of electrons per ZnO quantum dot is controlled by the electrochemical potential of the assembly; the charge of the electrons is compensated by ions present in the pores. We show with optical and electrical measurements that the injected electrons occupy the S, P, and D type conduction electron levels of the quantum dots; electron storage in surface states is not important. With this method of three-dimensional charge compensation, up to ten electrons per quantum-dot can be stored if the assembly is permeated with an aqueous electrolyte. The screening of the electron charge is less effective in the case of an assembly permeated with a propylene carbonate electrolyte solution. Long-range electron transport is studied with a transistor set-up. In the case of ZnO assemblies permeated with an aqueous electrolyte, two quantum regimes are observed corresponding to multiple tunnelling between the S orbitals (at a low occupation) and P orbitals (at a higher occupation). In a ZnO quantum-dot assembly permeated with a propylene carbonate electrolyte solution, there is a strong overlap between these two regimes.

Journal Article↗
PubMed2003

L-arginine transport in humans with cortisol-induced hypertension.

A deficient L-arginine-nitric oxide system is implicated in cortisol-induced hypertension. We investigate whether abnormalities in L-arginine uptake contribute to this deficiency. Eight healthy men were recruited. Hydrocortisone acetate (50 mg) was given orally every 6 hours for 24 hours after a 5-day fixed-salt diet (150 mmol/d). Crossover studies were performed 2 weeks apart. Thirty milliliters of blood was obtained for isolation of peripheral blood mononuclear cells after each treatment period. L-arginine uptake was assessed in mononuclear cells incubated with L-arginine (1 to 300 micromol/L), incorporating 100 nmol/L [3H]-l-arginine for a period of 5 minutes at 37 degrees C. Forearm [3H]-L-arginine extraction was calculated after infusion of [3H]-L-arginine into the brachial artery at a rate of 100 nCi/min for 80 minutes. Deep forearm venous samples were collected for determination of L-arginine extraction. Plasma cortisol concentrations were significantly raised during the active phase (323+/-43 to 1082+/-245 mmol/L, P<0.05). Systolic blood pressure was elevated by an average of 7 mm Hg. Neither L-arginine transport into mononuclear cells (placebo vs active, 26.3+/-3.6 vs 29.0+/-2.1 pmol/10 000 cells per 5 minutes, respectively, at an l-arginine concentration of 300 micromol/L) nor L-arginine extraction in the forearm (at 80 minutes, placebo vs active, 1 868 904+/-434 962 vs 2 013 910+/-770 619 disintegrations per minute) was affected by cortisol treatment; ie, that L-arginine uptake is not affected by short-term cortisol treatment. We conclude that cortisol-induced increases in blood pressure are not associated with abnormalities in the l-arginine transport system.

Adult↗
PubMed2003

Predictors of complication and suboptimal weight loss after laparoscopic Roux-en-Y gastric bypass: a series of 188 patients.

HYPOTHESIS: An analysis of patients undergoing laparoscopic Roux-en-Y gastric bypass (RYGB) may identify factors predictive of complication and of suboptimal weight loss. DESIGN: Inception cohort. SETTING: Metropolitan university hospital. PATIENTS: One hundred eighty-eight consecutive patients with severe obesity who met National Institutes of Health consensus guidelines for bariatric surgery. INTERVENTIONS: Laparoscopic RYGB. MAIN OUTCOME MEASURES: Complications requiring therapeutic intervention and percentage of excess body weight lost at 1 year after surgery. RESULTS: Of the 188 patients who underwent laparoscopic RYGB, 50 (26.6%) developed complications that required an invasive therapeutic intervention, including 2 deaths. The average follow-up was 351 days (range, 89-1019 days). Multivariate analysis by stepwise logistic regression identified surgeon experience, sleep apnea (P =.003; odds ratio, 3.0; 95% confidence interval, 1.3-7.1), and hypertension (P =.07; odds ratio, 2.0; 95% confidence interval, 1.0-4.0) as predictors of complications. The most common complication requiring therapeutic intervention was stricture at the gastrojejunal anastomosis, occurring in 27 patients (14.4%). Of the 115 patients who underwent surgery more than 1 year previously, 1-year follow-up data were available for 93 (81%). The body mass index (weight in kilograms divided by the square of height in meters) decreased from 53 +/- 8 preoperatively to 35 +/- 6 at 1 year. The mean +/- SD percentage of excess body weight lost at 1 year was 61% +/- 14%. Diabetes mellitus was negatively correlated with percentage of excess body weight lost at 1 year (P =.06). CONCLUSIONS: Surgeon experience, sleep apnea, and hypertension are associated with complications after laparoscopic RYGB. Diabetes mellitus may be associated with poorer postoperative weight loss.

Adult↗