PubMed Health⌕ Search

Biomedical subjects

K Reardon

Publications and source records attributed to K Reardon.

11 recordsLinked to original sources
PubMed2005

A new dominant distal myopathy affecting posterior leg and anterior upper limb muscles.

OBJECTIVE: To report a dominant, slowly progressive early onset distal myopathy with sparing of the tibialis anterior. METHODS: Twelve affected and two possibly affected members from an Australian kindred were examined and investigated by EMG, imaging studies, histopathology, and genetic analysis. RESULTS: Affected patients had a slowly progressive condition with symmetric, distal weakness and wasting of the anterior upper and posterior lower limbs, with sparing of tibialis anterior, even in advanced disease. All patients remained ambulant and there was no evidence of cardiac or respiratory muscle involvement. Serum creatine kinase levels were either normal or mildly elevated. Imaging studies showed widespread involvement of the posterior and lateral leg compartments. Proximal muscles were radiologically abnormal only in advanced disease. Muscles that were mildly affected clinically appeared normal on imaging. EMG in nine patients showed widespread myopathic changes. Muscle histopathology in four patients showed either end stage muscle or nonspecific myopathic findings without inflammation or vacuoles. Microsatellite markers for distal myopathy loci were analyzed and all known distal myopathy phenotype genes and linkage regions were formally excluded by multipoint analysis. CONCLUSIONS: The affected patients in this kindred display a clinically distinct myopathy, with selective involvement of posterior lower and anterior upper limb muscles. The genetic analysis suggests the existence of one more distal myopathy locus.

Adolescent↗
PubMed2002

X-linked myoclonic epilepsy with spasticity and intellectual disability: mutation in the homeobox gene ARX.

OBJECTIVE: To describe a new syndrome of X-linked myoclonic epilepsy with generalized spasticity and intellectual disability (XMESID) and identify the gene defect underlying this disorder. METHODS: The authors studied a family in which six boys over two generations had intractable seizures using a validated seizure questionnaire, clinical examination, and EEG studies. Previous records and investigations were obtained. Information on seizure disorders was obtained on 271 members of the extended family. Molecular genetic analysis included linkage studies and mutational analysis using a positional candidate gene approach. RESULTS: All six affected boys had myoclonic seizures and TCS; two had infantile spasms, but only one had hypsarrhythmia. EEG studies show diffuse background slowing with slow generalized spike wave activity. All affected boys had moderate to profound intellectual disability. Hyperreflexia was observed in obligate carrier women. A late-onset progressive spastic ataxia in the matriarch raises the possibility of late clinical manifestations in obligate carriers. The disorder was mapped to Xp11.2-22.2 with a maximum lod score of 1.8. As recently reported, a missense mutation (1058C>T/P353L) was identified within the homeodomain of the novel human Aristaless related homeobox gene (ARX). CONCLUSIONS: XMESID is a rare X-linked recessive myoclonic epilepsy with spasticity and intellectual disability in boys. Hyperreflexia is found in carrier women. XMESID is associated with a missense mutation in ARX. This disorder is allelic with X-linked infantile spasms (ISSX; MIM 308350) where polyalanine tract expansions are the commonly observed molecular defect. Mutations of ARX are associated with a wide range of phenotypes; functional studies in the future may lend insights to the neurobiology of myoclonic seizures and infantile spasms.

Adult↗
PubMed2001

Leukaemia inhibitory factor abrogates Paclitaxel-induced axonal atrophy in the Wistar rat.

A prominent side effect of Paclitaxel chemotherapy is sensorimotor peripheral neuropathy. Leukaemia inhibitory factor (LIF) supports the survival and regrowth of axotomised sensory and motor neurons and we therefore investigated if systemically administered LIF abrogated Paclitaxel-induced neuropathy. We found that whereas animals administered Paclitaxel alone exhibited a significant decrease in the percentage of large myelinated axons, this reduction was prevented by the co-administration of LIF.

Animals↗
PubMed1996

QT dispersion and RR variations on 12-lead ECGs in patients with congestive heart failure secondary to idiopathic dilated cardiomyopathy.

Increased QT dispersion, which has been proposed as a marker of ventricular repolarization inhomogeneity, may predispose to ventricular arrhythmias. Data on QT dispersion in patients with congestive heart failure are scarce. In this study, conventional 12-lead ECGs were recorded in 135 consecutive patients with congestive heart failure secondary to idiopathic dilated cardiomyopathy. Seventy-five patients were excluded from QT interval assessments due to one or more of the following reasons: (1) low amplitude of the T wave (n = 3), (2) atrial fibrillation (n = 26) and (3) bundle branch block (n = 46). QT dispersion was calculated as (1) QT-range: the difference between the maximum and minimum QT intervals on any of the 12 leads and (2) QT-SD: the standard deviation of the QT interval in all the 12 leads. RR intervals were measured in leads II, aVL, V2 and V5. QT-SD (20.85 +/- 5.00 ms) was significantly (r = 0.8997, P < 0.001) related to QT-range (65.65 +/- 15.77 ms), but not to the QT interval. Neither QT-range nor QT-SD was significantly related to age, left ventricular dimensions, left ventricular end diastolic pressure, left ventricular ejection fraction or left ventricular wall thickness. There was no significant difference in QT dispersion between survivors and those who died (n = 8) or were transplanted (n = 9) during 34 +/- 23 month follow-up. No significant difference in QT dispersion was observed between patients with and without ventricular tachycardia (> or = three consecutive beats) detected on 24-h Holter ECGs. RR interval variation was significantly lower in patients who died compared with survivors (standard deviation: 10.37 +/- 3.61 vs 36.02 +/- 35.03 ms, P < 0.001; coefficient of variance: 1.87 +/- 0.7% vs 4.50 +/- 4.9%, P = 0.001). This was also true in patients with bundle branch block. These observations suggest that QT dispersion in idiopathic dilated cardiomyopathy is not significantly related to either QT interval or cardiac size and function and does not predict death. The application of QT dispersion assessment is limited by the commonly encountered atrial fibrillation and bundle branch block in this patient population. However, reduced RR variation on standard 12-lead ECGs has important prognostic implications in these patients.

Adult↗
PubMed1995

Unexplained fever after aortic valve replacement with cryopreserved allografts.

The incidence of fever of unknown origin was studied in 3 groups of patients undergoing aortic valve replacement. Fever of unknown origin was defined as a fever greater than 38.3 degrees C detected after the third postoperative day and which initiated a negative "fever work-up." Fifty patients underwent aortic valve replacement using cyropreserved allografts. Of the 49 patients who survived the operation, 13 (26%) developed fever of unknown origin. Only 1 (2%) of 51 patients, and 4 (8%) patients undergoing aortic valve replacement with a mechanical prosthesis and porcine xenograft, respectively, developed fever of unknown origin (p = 0.0034). Fever of unknown origin after allograft aortic valve replacement developed between the fourth and sixth postoperative days, with no other associated symptoms or signs. It lasted for 24 to 48 hours, and resolved without treatment. Univariate analysis revealed that fever of unknown origin occurred in younger patients (39.9 +/- 9.4 versus 50.8 +/- 11.8 years of age). The mean white blood cell count in fever of unknown origin and afebrile patients were similar (10.4 +/- 3.2 and 8.9 +/- 2.3, p = NS), both of which were significantly lower than the white blood cell count in patients with documented infection (15.0 +/- 5.2, p = 0.02; p < 0.001). No association could be demonstrated between the fever of unknown origin and gender, previous endocarditis, operative technique, cardiopulmonary bypass or cross-clamp times, ABO match, or perioperative blood transfusions. We conclude that a significant number of patients undergoing allograft aortic valve replacement develop noninfectious postoperative fever. The etiology remains unknown, but low-grade rejection cannot be excluded.

Adult↗
PubMed1993

Proactive screening mammography counseling within the Cancer Information Service: results from a randomized trial.

In 1987, the Division of Cancer Prevention and Control, National Cancer Institute (NCI), funded a randomized trial of a proactive counseling protocol to promote screening mammography among age-eligible female callers to the Cancer Information Service (CIS). This protocol included interactive counseling by CIS counselors to help callers overcome barriers to screening mammography; this counseling was an extension of usual service and was combined with a 2-week follow-up mailout to reinforce the brief (6-minute) proactive telephone-counseling protocol. The screening-mammography counseling intervention was tested in two regional CIS offices using a randomized two-group design. Callers were randomly assigned to the intervention or control group based on the week of their call to the CIS (n = 1831 eligible female callers). Self-reported adherence to NCI screening-mammography guidelines was assessed from telephone interviews conducted at 12 months' follow-up (87% response rate). Among all CIS callers enrolled in this study, self-reported adherence to screening-mammography guidelines at 12 months' follow-up was 63.5%. The most frequently cited barriers to screening mammography reported by CIS callers were inconvenience/being too busy (52%), cost (36%), lack of physician referral (34%), no symptoms (34%), and fear of radiation (29%). A significant intervention effect on adherence behavior was found but only in one of the two test sites and only among CIS callers reporting total family income of $30,000 or more (odds ratio = 1.38, P = .04). The vast majority (90%) of CIS callers (both intervention and control subjects) endorsed the concept of proactive counseling by the CIS. The implications of these findings for the CIS and future research are discussed.

Adult↗
PubMed1984

Parent report as a means of administering the prescreening developmental questionnaire: an evaluation study.

The increasing emphasis on screening the pediatric population for developmental delays requires that rapid and efficient screening tests be developed and evaluated. This study assessed the ability of three rapid screening procedures to predict full Denver Developmental Screening Test (DDST) results. Ninety children were randomly assigned to one of three prescreening groups. The first group was prescreened with the Prescreening Developmental Questionnaire (PDQ), administered in the "standard" fashion, i.e., mother reads and answers 10 questions about her child's development. The second group was prescreened using a modified means of administering the PDQ (PDQ-M); a health care professional read each PDQ question to the mother. The third group was prescreened with the Alpern-Boll Developmental Profile II, a relatively lengthy procedure utilizing parent report information. All of the children were then tested with the DDST. Each of the prescreening procedures was highly predictive of performance on the DDST. The Alpern-Boll profile, as anticipated, demonstrated greater validity than the PDQ and PDQ-M on six of seven indices of prescreening test validity, generated from a four-group referral matrix. The PDQ-M was more similar to the Alpern-Boll on four indices, while the PDQ was more similar on three. It was judged that the two PDQ procedures were equivalent in their validity characteristics. The PDQ-M appears to be an acceptable means of rapidly screening preschool children for developmental delays.

Attitude↗
PubMedDate not supplied

Quadriceps muscle wasting persists 5 months after total hip arthroplasty for osteoarthritis of the hip: a pilot study.

AIMS: To determine whether additional muscle fibre wasting of the ipsilateral vastus lateralis muscle occurs in the early postoperative period after total hip arthroplasty for osteoarthritis of the hip and whether there is an improvement in preoperative measures of quadriceps muscle thickness, strength, pain and function over a 5-month postoperative period. METHODS: Twelve patients had ipsilateral needle quadriceps biopsy for muscle morphology and bilateral quadriceps muscle thickness ultrasound preoperatively, 5 days and 4 weeks postoperatively and a further muscle thickness measurement at 5 months. Seven additional patients and five age-matched control subjects had bilateral quadriceps muscle ultrasound thickness preoperatively, 6 weeks and 5 months postoperatively, with assessment of quadriceps muscle dynamometry, pain scores and Timed Up and Go (TUG) test. RESULTS: Preoperatively, all 19 patients demonstrated significant atrophy of the ipsilateral compared with the contralateral quadriceps muscle (P = 1.8 x 10(-7)) on muscle ultrasound, which persisted at 5 months follow up (P = 0.009). Muscle morphology preoperatively showed type 2A and 2B muscle fibre atrophy on needle muscle biopsy, with further atrophy of all three fibre types (P = 0.029) at 5 days postoperatively associated with a fibre type shift from type 1 to 2A fibres (P = 0.0011) at 1 month. There was improvement in hip pain postoperatively and a significant improvement in the TUG test (P = 0.007). However, there was no improvement in muscle strength on dynamometry. CONCLUSIONS: There is significant ipsilateral quadriceps atrophy and weakness with 2A and 2B fibre atrophy preoperatively in patients with osteoarthritis of the hip with exacerbation and further atrophy of all three fibre types 5 days postoperatively. Postoperative follow up showed that the reduction in ipsilateral quadriceps muscle thickness persisted at 5 months despite physical rehabilitation. Patients did note significant improvement in pain postoperatively and improvement on functional assessment with the TUG test. Other therapeutic strategies may have to be developed to reverse disuse muscle atrophy.

Aged↗
PubMedDate not supplied

Influencing spermicide use among low-income minority women.

Spermicides reduce the risk of a variety of sexually transmitted diseases (STDs) and hold promise for reducing the risk of human immunodeficiency virus (HIV) transmission. Many high-risk women are unaware that they are at risk for STDs and are unfamiliar with spermicides, however. A program promoting spermicides for the prevention of STDs was tested in a controlled intervention among low-income minority women seeking services in a public health family planning clinic. Women exposed to the intervention had more positive attitudes toward spermicides and used spermicides more than three times as often, on average, as control subjects. The best predictor of spermicide/condom use was knowledge of how to use spermicides correctly (OR 3.2, 95% CI 2.0, 5.0). Fear of acquired immune deficiency syndrome (AIDS) or STDs did not predict spermicide use. This study demonstrates that brief interventions in waiting areas of public health clinics can have a significant impact in helping women protect themselves from HIV and STDs.

Female↗