Search PubMed⌕ Search

Biomedical subjects

M J Henderson

Publications and source records attributed to M J Henderson.

At least 19 recordsLinked to original sources

Carnitine transporter defect: diagnosis in asymptomatic adult women following analysis of acylcarnitines in their newborn infants.

Carnitine transporter defect (CTD) is an autosomal recessive disorder characterized by episodes of non-ketotic hypoglycaemia, hyperammonaemia and liver disease, or by the development of cardiomyopathy, both of which occur in infancy and childhood. Blood carnitine concentrations are extremely low. The diagnosis can be confirmed by finding abnormal fat oxidation and carnitine uptake in skin fibroblasts. The condition has not previously been thought to present later in life or to be benign. We report the identification of four women discovered to have CTD as a consequence of finding low carnitine concentrations in the cord blood or newborn samples from their infants. All four mothers had been asymptomatic and none had a cardiomyopathy.

Adult↗

Reference data for cerebrospinal fluid and the utility of amino acid measurement for the diagnosis of inborn errors of metabolism.

BACKGROUND: Cerebrospinal fluid (CSF) amino acid analysis is fundamental to the investigation of several inherited metabolic diseases, particularly those presenting with unexplained seizures. CSF glycine measurement is often crucial to the diagnosis of glycine encephalopathy (GE), low CSF serine concentrations are characteristic of 3-phosphoglycerate dehydrogenase deficiency (3-PGDD) and the presence of sulphocysteine is pathognomonic of sulphite oxidase deficiency (SOD), and a vital clue to molybdenum cofactor deficiency (MCD). Limited information is available in the literature on reference values of amino acids in CSF during infancy and CSF samples from healthy individuals are not easily obtained. METHODS: In order to establish paediatric CSF amino acid reference ranges, we performed a retrospective analysis of all quantitative CSF amino acid data collected in our laboratory over a five-year period. Amino acid analysis was performed using ion-exchange chromatography on a Biochrom-20 amino acid analyser with ninhydrin detection. CSF samples were collected from infants undergoing investigation for unexplained seizures. RESULTS: About 18 of the 95 samples received were excluded from the reference data-set; one was from a patient in whom a diagnosis of GE was confirmed by enzyme analysis, one was from a patient with CSF sulphocysteine of 19 micromol/L in whom a diagnosis of SOD was confirmed by enzyme analysis; the remaining 16 were clearly bloodstained (n = 4) or xanthochromic (n = 12). Frequency of distribution analysis revealed that concentration values for each amino acid demonstrated a right-skewed distribution which was not normalized by log transformation. Data were therefore analysed using non-parametric descriptive statistics and reference ranges were defined by the 2.5th and 97.5th centile limits. CONCLUSIONS: Our reference data were derived from 77 CSF samples taken from 77 infants. Median CSF glycine concentration was 9 micromol/L with a reference range of 3-19 micromol/L. For serine, the median CSF concentration was 52 micromol/L with a reference range of 25-105 micromol/L. Sulphocysteine was not normally present in detectable quantities (<1 micromol/L).

Amino Acid Metabolism, Inborn Errors↗

Remembering Sophie.

Explore the source record for details and available documents.

Aged, 80 and over↗

Time-dependent changes in the formation of titania-based films at the air-water interface.

The growth of surfactant-assisted titanium dioxide-based films at the air-water interface previously reported (Henderson et al. Aust. J. Chem. 2003, 56, 933) has been monitored with a time resolution of minutes over the whole growth period by X-ray energy-dispersive reflectometry. Two new phenomena are described: (a) short-term shifts in the Bragg spacing of the layer structure and (b) the periodic disappearance of the diffraction from the film. We associate these with changes in the chemistry of the reacting mixture, with changes in the packing of the templated titanium species, and with macroscopic and (possibly) microscopic rippling of the solid film during growth.

Journal Article↗

Cholesterol granuloma of the frontal sinus.

It is common to see cholesterol granuloma in the mastoid air cells, less common in the orbit, and uncommon in the paranasal sinuses. Cholesterol granuloma is thought to be due to an interruption to normal aeration with impaired lymphatic drainage, resulting in a closed cavity where it may form. These expanding cysts cause bone destruction and compression of the surrounding structures that lead to clinical symptoms. Diagnosis and management of cholesterol granuloma cysts can be challenging. Magnetic resonance imaging (MRI) and computed tomographic (CT) scans are usually diagnostic. We present a rare case of cholesterol granuloma in the frontal sinus, few cases have been reported in the literature.

Aged↗

Alcohol expectancies and motives in a substance abusing male treatment sample.

Although prior research has demonstrated the utility of both alcohol expectancies and drinking motives in the prediction of alcohol use and problems, the specific relationship between these domains has not been examined in a clinical sample. One-hundred, forty-seven veterans on an inpatient substance abuse unit completed questionnaires measuring alcohol expectancies and alcohol motives and provided information on their alcohol consumption and related problems. Covariance structure modeling was used to test four theoretically competing models. Findings indicated that: (1) motives mediate the effects of expectancies on use and problems and expectancies do not exert an independent influence on consumption and alcohol problems and (2) contrary to past findings, alcohol use only partially mediates the relationship between enhancement motives and alcohol problems.

Adaptation, Psychological↗

Novelty seeking as a predictor of treatment retention for heroin dependent cocaine users.

This study examined the relationship between novelty seeking between treatment retention and among heroin dependent cocaine users. Participants were treated with buprenorphine maintenance and contingency management. The Tridimensional Personality Questionnaire's (TPQ) Novelty Seeking scale was administered to 68 participants prior to buprenorphine induction. Demographics, mood and anxiety disorders, antisocial personality disorder, and substance use were also assessed. Variables with significant relationships with overall retention were entered into a logistic regression analysis. In addition, using a survival analysis, all variables with significant relationships with time to drop-out were entered into a multivariate proportional hazards regression with time dependent covariates. Results demonstrated that although high novelty seekers, in comparison to low novelty seekers, were more likely to drop-out by the end of treatment, they had higher retention rates during the early phases of treatment. It is suggested that buprenorphine and contingency management were viewed by participants as novel treatment components and thus facilitated high novelty seekers' success early in treatment. If replicated, results suggest that inclusion of novel treatment components might facilitate retention among this at-risk group.

Adult↗

Micro syndrome in Muslim Pakistan children.

OBJECTIVE: To date, Micro syndrome has been reported in only three children from one family. We describe an additional 14 children from 11 families. DESIGN: Retrospective case series. PARTICIPANTS: Fourteen children from 11 families attending one of five British hospitals. MAIN OUTCOME MEASURES: The following features were documented: pre- and postoperative eye findings, electrophysiologic analysis, systemic abnormalities, development, neuroimaging, genealogy, geographic origin of family. RESULTS: We expand and modify the description of ocular and electrophysiologic findings in Micro syndrome. The eye findings of microphakia, microphthalmos, characteristic lens opacity, and atonic pupils were the presenting feature in all infants and were the most reliable diagnostic signs in the immediate postnatal period. Cortical visual impairment, microcephaly, and developmental delay were not always detectable initially; they developed in all children by 6 months of age. Microgenitalia were a useful diagnostic clue in affected males only. Therefore, eye features were more consistently useful in determining diagnosis than dysmorphology or brain imaging. The families of all the children originate from the Muslim population of Northern Pakistan. Inheritance is likely to be autosomal recessive. CONCLUSIONS: Micro syndrome usually presents to the ophthalmologist, who may be able to make the diagnosis on the basis of characteristic eye findings combined with ethnic origin. Initially, the nature and severity of nonophthalmic features are not apparent. Early diagnosis of the underlying condition is important to guide management of the cataracts, glaucoma, and developmental delay. It is helpful for the family and medical staff to be aware of the low level of vision that develops despite optimal ophthalmic intervention. Genetic counseling extending into the wider family is particularly important in view of the high rate of consanguinity.

Adolescent↗

Comparison of past and current barriers to novice nurse practitioner practice: The California perspective.

Novice nurse practitioners (NPs) face unique obstacles to practice. Few studies examine factors influencing early NP clinical performance. Therefore, this research project was designed to collect data from members of an NP professional organization who were asked to identify barriers encountered within the first 3 years of practice. Responses were received from 243 beginning and more experienced NPs. The top three barriers named were lack of public knowledge, lack of positions for NPs, and a lower salary than anticipated. The promotion of NP assets through expanded media coverage and individual educational efforts, the national standardization of the role, and the elimination of restrictive practice legislation can help reduce current barriers. Through the efforts of individuals, NP professional groups, and legislators, existing practice constraints can be mitigated, potential barriers anticipated, and solutions generated to ensure the continued success of this essential advanced practice role.

Adult↗

Successful treatment of carbohydrate deficient glycoprotein syndrome type 1b with oral mannose.

An Asian girl presented with failure to thrive, congenital hepatic fibrosis, protein losing enteropathy, and hypoglycaemia. Phosphomannose isomerase activity in skin fibroblasts was reduced. She is homozygous for a mutation, D131N, in the phosphomannose isomerase gene (PM1), consistent with the diagnosis of carbohydrate deficient glycoprotein syndrome type 1b. She responded to oral mannose treatment.

Administration, Oral↗

Quality of life and locus of control of migraineurs.

Advanced practice nurses (APNs) are essential primary healthcare providers actively engaged in health promotion, illness prevention, and the management of acute and chronic diseases. The purpose of this study was to measure the quality of life and locus of control (LOC) among three different groups of migraineurs. A retrospective quantitative study was conducted using Ferrans and Powers' (1985) Quality of Life Index and Martin, Holroyd, and Penzien's (1990) Headache Specific Locus of Control questionnaire. The analysis of 79 adult migraineurs indicated that those who received headache education had a higher quality of life and higher external LOC scores than those without the intervention. This study's findings reinforce the notion that disease-specific education is an effective practice intervention. APNs can positively affect the quality of life for migraineurs by providing an educational intervention as part of high-quality, accessible, and cost-effective primary care.

Adolescent↗

Measurement of phenylalanine and tyrosine in plasma by high-performance liquid chromatography using the inherent fluorescence of aromatic amino acids.

An isocratic high-performance liquid chromatography (HPLC) method is described using the natural fluorescence of phenylalanine and tyrosine compared with that of an internal standard N-methyl phenylalanine. Plasma precipitated with 6% perchloric acid was separated isocratically using a base-deactivated C18 column with 5% acetonitrile in water as the mobile phase. Fluorescent measurements at an excitation wavelength of 215 nm and emission 283 nm showed only three peaks for tyrosine, phenylalanine and the internal standard eluting within 9 min. Inter-batch coefficients of variation for phenylalanine were 2.9% and 1.8% at levels of 70 and 567 mumol/L, respectively, and 2.9% at a level of 63 mumol/L for tyrosine. The results for phenylalanine for this method showed a small mean positive bias (11 mumol/L) when compared with the target all-method means for UK National External Quality Assessment Scheme samples (n = 31). The results for tyrosine showed a small positive mean bias (10 mumol/L) when compared with an ion-exchange chromatographic method (n = 40). This method provides a quick and simple alternative to those using HPLC with pre- or post-column derivatization for monitoring patients with phenylketonuria. It is also less subject to interferences than HPLC methods using ultraviolet detection, particularly for the early eluting tyrosine peak.

Chromatography, High Pressure Liquid↗