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J M Miller

Publications and source records attributed to J M Miller.

At least 19 recordsLinked to original sources
PubMed2006

Revisiting reliability of quantified perineal ultrasound: Bland and Altman analysis of a new protocol for the rectangular coordinate method.

AIMS: This study tested the reliability of a new protocol for the rectangular coordinate method of quantifying perineal ultrasound. METHODS: Representative scans of healthy primiparous females were quantified by positioning a pubic bone template, drawn onto an acetate sheet containing x-y axes, over scans, by aligning the x-axis with the pubic bone central axis. Values for x (D(x)) and y (D(y)) located the urethrovesical junction (UVJ) at Rest, and at maximal Valsalva and Kegel. Range of motion (V-K) was calculated. Bland and Altman analysis, correlations, and t-tests determined intra- and inter-rater reliability, and variance due to designation of the pubic bone central axis (template control). RESULTS: Correlations averaged 0.72, 0.70, and 0.92 for intra-rater, inter-rater, and template control experiments. D(x) Rest, D(x) Kegel, and V-K were reliable in all experiments. First and second measures for inter-rater D(y) Rest and D(y) Kegel, and template control D(y) Valsalva were significantly different. Bland and Altman analysis showed D(y) Rest, D(y) Kegel, and D(x) and D(y) Valsalva for both reliability experiments to have limits of agreement (LOA's) large enough to explain >or=50% of the actual value ranges. Template control LOA's explained <or=30% of the actual value ranges. CONCLUSIONS: The reliability of this protocol varied according to the conditions analyzed; accurate reliability assessment of all conditions required Bland and Altman analysis; and the designation of the pubic bone central axis remained a source of variance between investigators. Our results suggest Bland and Altman analysis be used with each study that quantifies perineal ultrasound.

Adult↗
PubMed2006

Experimental second passage of chronic wasting disease (CWD(mule deer)) agent to cattle.

To compare clinicopathological findings in first and second passage chronic wasting disease (CWD(mule deer)) in cattle, six calves were inoculated intracerebrally with brain tissue derived from a first-passage CWD-affected calf in an earlier experiment. Two uninoculated calves served as controls. The inoculated animals began to lose both appetite and weight 10-12 months later, and five subsequently developed clinical signs of central nervous system (CNS) abnormality. By 16.5 months, all cattle had been subjected to euthanasia because of poor prognosis. None of the animals showed microscopical lesions of spongiform encephalopathy (SE) but PrP(res) was detected in their CNS tissues by immunohistochemistry (IHC) and rapid Western blot (WB) techniques. Thus, intracerebrally inoculated cattle not only amplified CWD PrP(res) from mule deer but also developed clinical CNS signs in the absence of SE lesions. This situation has also been shown to occur in cattle inoculated with the scrapie agent. The study confirmed that the diagnostic techniques currently used for diagnosis of bovine spongiform encephalopathy (BSE) in the US would detect CWD in cattle, should it occur naturally. Furthermore, it raised the possibility of distinguishing CWD from BSE in cattle, due to the absence of neuropathological lesions and to a distinctive multifocal distribution of PrP(res), as demonstrated by IHC which, in this study, appeared to be more sensitive than the WB technique.

Animals↗
PubMed2006

First and second cattle passage of transmissible mink encephalopathy by intracerebral inoculation.

To compare clinicopathologic findings of transmissible mink encephalopathy (TME) with other transmissible spongiform encephalopathies (TSE, prion diseases) that have been shown to be experimentally transmissible to cattle (sheep scrapie and chronic wasting disease [CWD]), two groups of calves (n = 4 each) were intracerebrally inoculated with TME agents from two different sources (mink with TME and a steer with TME). Two uninoculated calves served as controls. Within 15.3 months postinoculation, all animals from both inoculated groups developed clinical signs of central nervous system (CNS) abnormality; their CNS tissues had microscopic spongiform encephalopathy (SE); and abnormal prion protein (PrP(res)) as detected in their CNS tissues by immunohistochemistry (IHC) and Western blot (WB) techniques. These findings demonstrate that intracerebrally inoculated cattle not only amplify TME PrP(res) but also develop clinical CNS signs and extensive lesions of SE. The latter has not been shown with other TSE agents (scrapie and CWD) similarly inoculated into cattle. The findings also suggest that the diagnostic techniques currently used for confirmation of bovine spongiform encephalopathy (BSE) would detect TME in cattle should it occur naturally. However, it would be a diagnostic challenge to differentiate TME in cattle from BSE by clinical signs, neuropathology, or the presence of PrP(res) by IHC and WB.

Animals↗
PubMed2006

Abnormal prion protein in ectopic lymphoid tissue in a kidney of an asymptomatic white-tailed deer experimentally inoculated with the agent of chronic wasting disease.

Chronic wasting disease (CWD), a transmissible spongiform encephalopathy (TSE) of deer and elk, is one of a group of fatal, neurologic diseases that affect several mammalian species, including human beings. Infection by the causative agent induces accumulations of an abnormal form of prion protein (PrPres) in nervous and lymphoid tissues. This report documents the presence of PrPres within ectopic lymphoid follicles in a kidney of a white-tailed deer that had been experimentally inoculated by the intracerebral route with CWD 10 months previously. The deer was nonclinical, but spongiform lesions characteristic of TSE were detected in tissues of the central nervous system (CNS) and PrPres was seen in CNS and in lymphoid tissues by immunohistochemistry. The demonstration of PrPres in lymphoid tissue in the kidney of this deer corroborates a recently published finding of PrPres in lymphoid follicles of organs other than CNS and lymphoid tissues in laboratory animals with TSE (scrapie).

Animals↗
PubMed2006

Tibial tuberosity advancement in 65 canine stifles.

The tibial tuberosity advancement (TTA) procedure was developed to treat dogs with cranial cruciate ligament deficient stifles. A retrospective, descriptive study was performed on 57 dogs that underwent unilateral or bilateral TTA. Medical records were reviewed and pre-, postoperative and follow-up radiographs were evaluated for patellar ligament-tibial plateau angle (alpha), distance of the tibial tuberosity advancement and progression of degenerative joint disease. A questionnaire was sent to all owners to obtain their assessment of the procedural outcome. Sixty-five stifles in 57 dogs received a TTA. Mean age was 5.2 +/- 2.5 years while mean weight was 39.7 +/- 11.9 kg. Eighteen breeds were represented with Labrador retrievers and mixed breeds predominating. The mean duration of lameness prior to surgery was 6.2 +/- 6.7 months, with a median lameness score of 3/4. Fifty-nine percent of cases encountered complications, the majority of which were minor. Major post-operative complications were uncommon but consisted of implant failure, tibial crest displacement and medial meniscal tears. The mean radiographic preoperative angle alpha was 100 degrees, while the postoperative was 95.5 degrees. Mean osteoarthrosis scores were significantly different between preoperative and follow-up radiographs with 67% of cases showing radiographic progression. Seventy percent of owners responded to the survey with overall outcome considered good to excellent in 90%. Activity level was improved in 90% of responses. TTA subjectively appears to be a useful alternative in the management of cranial cruciate ligament disease. Few severe complications were encountered. Good clinical outcome and owner satisfaction was reported with the procedure in this set of cases.

Animals↗
PubMed2005

Non-invasive half millimetre 32 detector row computed tomography angiography accurately excludes significant stenoses in patients with advanced coronary artery disease and high calcium scores.

OBJECTIVE: To show an overall diagnostic accuracy > or = 90% for detection of > or = 50% stenoses by coronary half millimetre 32 detector row computed tomography angiography (32 x 0.5-MDCTA) in patients with advanced coronary artery disease (CAD) and a high likelihood of raised calcium scores. METHODS: ECG gated 32 x 0.5-MDCTA (32 x 0.5 mm cross sections, 0.35 x 0.35 x 0.35 mm3 isotropic voxels, 400 ms rotation) was performed after injection of iodixanol (120 ml, 320 mg/ml) in 30 consecutive patients (25 men, mean (SD) age 59 (13) years, body mass index 26.2 (4.9) kg/m2). Native arteries, including > or = 1.5 mm branches, and bypass grafts were screened for > or = 50% stenoses. Stents were excluded. Conventional coronary angiography (performed 18 (12) days before 32 x 0.5-MDCTA) was analysed by quantitative coronary angiography. RESULTS: Median Agatston calcium score was 510 (range 3-5066). Sensitivity, specificity, and positive and negative predictive values for detection of > or = 50% stenoses in native arteries were 76% (29 of 38), 94% (190 of 202), 71% (29 of 41), and 96% (190 of 199), respectively. Overall diagnostic accuracy was 91% (219 of 240). Due to the following artefacts 20% (69 of 352) of the vessels were excluded: motion, noise, and low contrast enhancement isolated or in combination (45 of 69 (65%)); image distortion by implantable cardioverter-defibrillator or pacemaker leads (18 of 69 (26%)); and blooming secondary to severe calcification (6 of 69 (9%)). CONCLUSIONS: Coronary 32 x 0.5-MDCTA accurately excludes > or = 50% stenoses in patients with advanced CAD and high calcium scores with an overall diagnostic accuracy of 91%.

Adult↗
PubMed2005

Cognitive and behavioral effects of lamotrigine and topiramate in healthy volunteers.

BACKGROUND: The relative cognitive and behavioral effects of lamotrigine (LTG) and topiramate (TPM) are unclear. METHODS: The authors directly compared the cognitive and behavioral effects of LTG and TPM in 47 healthy adults using a double-blind, randomized crossover design with two 12-week treatment periods. During each treatment condition, subjects were titrated to receive either LTG or TPM at a target dose of 300 mg/day for each. Neuropsychological evaluation included 17 measures yielding 41 variables of cognitive function and subjective behavioral effects. Subjects were tested at the end of each antiepileptic drug (AED) treatment period and during two drug-free conditions (pretreatment baseline and 1 month following final AED withdrawal). RESULTS: Direct comparison of the two AEDs revealed significantly better performance on 33 (80%) variables for LTG, but none for TPM. Even after adjustment for blood levels, performance was better on 19 (46%) variables for LTG, but none for TPM. Differences spanned both objective cognitive and subjective behavioral measures. Comparison of TPM to the non-drug average revealed significantly better performance for non-drug average on 36 (88%) variables, but none for TPM. Comparison of LTG to non-drug average revealed better performance on 7 (17%) variables for non-drug average and 4 (10%) variables for LTG. CONCLUSIONS: Lamotrigine produces significantly fewer untoward cognitive and behavioral effects compared to topiramate (TPM) at the dosages, titrations, and timeframes employed in this study. The dosages employed may not have been equivalent in efficacy. Future studies are needed to delineate the cognitive and behavioral effects of TPM at lower dosages.

Adult↗
PubMed2005

Detection of Mycobacterium avium subspecies paratuberculosis in free-ranging bison (Bison bison) by PCR.

Bacterial culture is the 'gold standard' for detecting Mycobacterium avium subspecies paratuberculosis (MAP) infection, but is time consuming, laborious, and recovery of organism varies with species of animal tested. PCR has been used for detection of MAP DNA in feces and tissues. We used PCR to detect MAP DNA isolated from tissues from 25 free-ranging North American bison (Bison bison), each with clinical signs compatible with Johne's disease. We report the performance of PCR to detect MAP DNA in both frozen and paraffin-embedded ileum, jejunum, and ileocecal lymph node samples collected at the time of slaughter. Specific oligonucleotide primers for PCR amplification were derived from 16S rRNA sequence M. avium subspecies (MAs) and insertion elements IS1245 (MAs avium), IS901 (MAs avium), IS900 (MAP), and hspX (MAP). Genomic DNA samples were prepared three different ways; crude DNA from frozen tissues, crude DNA from paraffin-embedded tissues, and purified DNA from paraffin-embedded tissues. An animal was considered infected if MAP DNA was detected in at least two separate tissues using the IS900 primer set. Using these criteria, 25 of 25 bison tested were positive for MAP. The data indicate that these free-ranging bison have been infected by MAP.

Animals↗
PubMed2005

Post-exposure treatment attenuates noise-induced hearing loss.

Reactive oxygen species (ROS) and reactive nitrogen species (RNS) are involved in sensory cell and neural death in the peripheral nervous system, including damage induced by noise trauma. Antioxidant administration prior to or concomitant with noise exposure can prevent auditory deficits, but the efficacy of a delayed treatment is not known. We have recently found continued reactive oxygen species/reactive nitrogen species formation in the ear for 7-10 days following noise exposure and reasoned that antioxidant intervention during this period should also reduce noise-induced hearing loss. Guinea-pigs were subjected to 4 kHz octave band noise at 120 decibels sound- pressure-level (dB SPL) for 5 hours and received treatment with ROS and RNS scavengers (salicylate and trolox) beginning 3 days prior, 1 hour, 1, 3, or 5 days after noise exposure. Auditory thresholds were assessed by sound-evoked auditory brainstem response at 4, 8, and 16 kHz, before and 10 days after noise exposure. Hair cell damage was analyzed by quantitative histology, and free radical activity was determined immunohistochemically via 4-hydroxynonenal and nitrotyrosine as markers of reactive oxygen species and reactive nitrogen species action. Delivered up to 3 days after noise exposure, salicylate and trolox significantly reduced auditory brainstem response deficits, reduced hair cell damage, and decreased reactive oxygen species and reactive nitrogen species formation. Earlier drug treatment was more effective than later treatment. Our results detail a window of opportunity for rescue from noise trauma, and provide evidence for both morphological and functional protection by delayed pharmacological intervention.

Aldehydes↗
PubMed2005

Second passage of sheep scrapie and transmissible mink encephalopathy (TME) agents in raccoons (Procyon lotor).

To determine the transmissibility and pathogenicity of sheep scrapie and transmissible mink encephalopathy (TME) agents derived from raccoons (first passage), raccoon kits were inoculated intracerebrally with either TME (one source) or scrapie (two sources-each in separate groups of raccoons). Two uninoculated raccoon kits served as controls. All animals in the TME-inoculated group developed clinical signs of neurologic dysfunction and were euthanatized between postinoculation month (PIM) 6 and 8. Raccoons in the two scrapie-inoculated groups manifested similar clinical signs of disease, but such signs were observed much later and the animals were euthanized between PIM 12 and 18. Necropsy revealed no gross lesions in any of the raccoons. Spongiform encephalopathy was observed by use of light microscopy, and the presence of protease-resistant prion protein (PrPres) was detected by use of immunohistochemical (IHC) and Western blot analytic techniques. Results of IHC analysis indicated a distinct pattern of anatomic distribution of PrPres in the TME- and scrapie-inoculated raccoons. These findings confirm that TME and sheep scrapie are experimentally transmissible to raccoons and that the incubation periods and IHC distribution for both agents are distinct. Therefore, it may be possible to use raccoons for differentiating unknown transmissible spongiform encephalopathy (TSE) agents. Further studies, with regard to the incubation period and the pattern of PrPres deposition by use of IHC analysis in bovine spongiform encephalopathy and for other isolates of scrapie, chronic wasting disease, and TME in raccoons are needed before the model can be further characterized for differentiation of TSE agents.

Animals↗
PubMed2005

Lower serum magnesium levels are associated with more rapid decline of renal function in patients with diabetes mellitus type 2.

AIMS: Hypomagnesemia has been implicated in adversely affecting diabetic complications. This is a retrospective study designed to determine whether there is any association between serum magnesium concentration [Mg2+] and the rate of renal function deterioration, as determined by the slope of serum creatinine reciprocals versus time (1/SCr-vs-t), in patients with diabetes mellitus type 2 (DM2). MATERIALS AND METHODS: DM2 patients without known kidney disease seen at Olive View-UCLA Medical Center for any reason during January-March 2001 were included. For each patient, all available data from our electronic database for [Mg2+], hemoglobin A(1C) (HbA(1C), serum creatinine (SCr), lipid profiles, routine urinary analysis, as well as history of hypertension and pharmacy profiles were retrieved. The average of all parameters obtained and linear regression analyses for the slope of 1/SCr-vs-t plot were performed for each patient. Patients were stratified by gender and divided into four groups based on increasing [Mg2+]. Correlations between each parameter including the slope of 1/SCr-vs-t and the four magnesium groups were analyzed. RESULTS: 252 males and 298 females with a mean follow-up of 62.6 +/- 22.5 months were included. Patients belonging to lower [Mg2+] groups for both genders had significantly worse slopes of 1/SCr-vs-t plot independent of the presence of hypertension and use of ACEI/ARB, diuretics, HMG-CoA enzyme inhibitors or aspirin. In a multivariate regression analysis controlling for age, HbA(1C) and various components of the lipid profile, [Mg2+] remained an independent predictor for the slope of 1/SCr-vs-t. A trend for worse proteinuria based on routine urinary analysis was observed among patients belonging to the lowest [Mg2+] group. CONCLUSIONS: Lower [Mg2+] is associated with a faster renal function deterioration rate in DM2 patients.

Biomarkers↗
PubMed2004

Failure to detect prion protein (PrPres) by immunohistochemistry in striated muscle tissues of animals experimentally inoculated with agents of transmissible spongiform encephalopathy.

Transmissible spongiform encephalopathies (TSEs) are fatal neurologic diseases. Infection by the causative agent, a prion, induces accumulations of an abnormal form of prion protein (PrP(res)) in tissues of nervous and lymphoid systems. Presence of characteristic histopathologic changes (spongiform encephalopathy) and detection of protease-resistant PrP(res) in neural and lymphoid tissues are the basis of currently available methods for diagnosis of TSEs. In this study, samples of striated muscle tissues (tongue, heart, diaphragm, and masseter muscle) from 20 animals (cattle, sheep, elk, and raccoons) were examined for PrP(res) by immunohistochemistry (IHC). All the animals had developed a TSE after experimental inoculation. PrP(res) was found by IHC in the brain but not in the muscle tissues of all the animals examined. These findings are contradictory to recently published reports of laboratory animals with TSEs, where these altered prion proteins were detected in tongue and other striated muscles. Further testing of muscle tissues is needed to confirm the findings of the present study.

Animals↗
PubMed2004

Mechanomyographic time and frequency domain responses of the vastus medialis muscle during submaximal to maximal isometric and isokinetic muscle actions.

The purpose of this study was to examine the patterns for the mechanomyographic (MMG) amplitude and mean power frequency (MPF) versus torque relationships during isometric and isokinetic muscle actions. Ten adults (mean age +/- SD = 22 +/- 1 y) volunteered to perform isometric and isokinetic leg extension muscle actions at 10, 20, 30, 40, 50, 60, 70, 80, 90, and 100% of peak torque on a Cybex II dynamometer. A piezoelectric crystal contact sensor was placed on the vastus medialis to detect the MMG signal. Regression analyses indicated that for the isometric muscle actions, the relationships for MMG amplitude (R2 = 0.998) and MPF (R2 = 0.987) versus torque were cubic. For the isokinetic muscle actions, the relationships for MMG amplitude (r2 = 0.927) and MPF (r2 = 0.769) versus torque were linear. The different patterns for MMG amplitude and frequency may reflect differences in the motor control strategies that modulate torque production for isometric versus dynamic muscle actions.

Adult↗
PubMed2003

Effects of hepatitis A vaccination on atherogenesis in a murine model.

Our laboratory demonstrated that seropositivity to hepatitis A virus (HAV) independently predicts risk for coronary artery disease (CAD). As these findings are based only on the presence of HAV-specific antibodies, and not infectious virus, this prompted questions regarding possible effects of HAV vaccines on CAD development. If seropositivity to HAV alone, resulting from HAV vaccination, leads to increased atherogenesis, this raises important issues regarding the benefit of protection against HAV infection vs the risk of developing CAD. This study examines the effect of HAV vaccination on atherosclerosis development in a cholesterol-fed mouse model. Animals either received HAV vaccine, adjuvant, or saline. After 15 weeks, no significant differences were found in lesion area between the groups: HAV vaccine, 13,470 microm2; adjuvant, 16,332 microm2 and saline, 14,356 microm2. Only animals receiving HAV vaccination developed HAV-specific IgG. Thus, in this mouse model, vaccination against HAV does not contribute to the development of atherosclerosis.

Animals↗
PubMed2003

Early induction of humoral and cellular immune responses during experimental Mycobacterium avium subsp. paratuberculosis infection of calves.

Johne's disease (paratuberculosis) of cattle is widespread and causes significant economic losses for producers due to decreased production and poor health of affected animals. The chronic nature of the disease and the lack of a reproducible model of infection hinder research efforts. In the present study, instillation of Mycobacterium avium subsp. paratuberculosis into the tonsillar crypts of neonatal calves resulted in peripheral colonization as detected by antemortem culture of feces and postmortem (320 days postchallenge) culture of intestinal tissues. Antigen-specific blastogenic, gamma interferon (IFN-gamma), and nitric oxide responses by blood mononuclear cells from infected calves exceeded prechallenge responses beginning 194 days postchallenge. Upon in vitro stimulation with paratuberculosis antigens, CD4(+) cells from infected calves proliferated, produced IFN-gamma, and increased expression of CD26 and CD45RO (indicative of an activated memory phenotype). Utilizing a lipoarabinomannan-based enzyme-linked immunosorbent assay, specific serum immunoglobulin was detected as early as 134 days postchallenge and generally increased after this time point. Two antigens of approximately 50 and approximately 60 kDa were particularly immunodominant early in infection, as shown by immunoblot with serum collected within 2 weeks postchallenge. Findings indicate that the intratonsillar inoculation route will prove useful as an experimental model for paratuberculosis infection. Additionally, this study confirms that mycobacteria-specific antibody is detectable early in the course of experimental Johne's disease, even preceding the development of specific cell-mediated responses.

Animals↗
PubMed2003

Preliminary observations on the experimental transmission of scrapie to elk (Cervus elaphus nelsoni) by intracerebral inoculation.

To determine the transmissibility of scrapie to Rocky Mountain elk (Cervus elaphus nelsoni), six elk calves were inoculated intracerebrally with brain suspension from sheep naturally affected with scrapie. One elk developed a brain abscess and was euthanatized at 7 weeks postinoculation (PI), and two others died at 6 and 15 months PI because of physical injuries. At 25 and 35 months PI, two other elk died after brief terminal neurologic episodes. Necropsy of these revealed moderate weight loss but no other gross lesions. Microscopically, characteristic lesions of spongiform encephalopathy were seen throughout the brains and the spinal cords, and in both cases these tissues were positive for PrP(res) by immunohistochemistry. Brains of both animals were positive for PrP(res) by western blot and for scrapie-associated fibrils (SAFs) by negative stain electron microscopy. PrP(res) and SAFs were not detected in the three elk that died or were euthanatized because of coincidental causes. Over 3.5 years after initiation of this experiment, the one remaining inoculated elk and two uninoculated (control) elk are alive and apparently healthy. These preliminary findings demonstrate that 1) sheep scrapie agent can be transmitted to elk by intracerebral inoculation; 2) the infection can result in severe, widely distributed spongiform change and accumulations of PrP(res) in the central nervous system (CNS); and 3) based on the examination of a limited number of CNS sections from two cases, this condition cannot be distinguished from chronic wasting disease with currently available diagnostic techniques.

Animals↗
PubMed2002

Large-scale, decelerating, relativistic x-ray jets from the microquasar XTE J1550-564.

We have detected, at x-ray and radio wavelengths, large-scale moving jets from the microquasar XTE J1550-564. Plasma ejected from near the black hole traveled at relativistic velocities for at least 4 years. We present direct evidence for gradual deceleration in a relativistic jet. The broadband spectrum of the jets is consistent with synchrotron emission from high-energy (up to 10 tera-electron volts) particles that were accelerated in the shock waves formed within the relativistic ejecta or by the interaction of the jets with the interstellar medium. XTE J1550-564 offers a rare opportunity to study the dynamical evolution of relativistic jets on time scales inaccessible for active galactic nuclei jets, with implications for our understanding of relativistic jets from Galactic x-ray binaries and active galactic nuclei.

Journal Article↗