Biomedical subjects

L N Jensen

Publications and source records attributed to L N Jensen.

10 recordsLinked to original sources

PubMed1998

Autosomal dominant pure spastic paraplegia: a clinical, paraclinical, and genetic study.

OBJECTIVES: At least three clinically indistinguishable but genetically different types of autosomal dominant pure spastic paraplegia (ADPSP) have been described. In this study the clinical, genetic, neurophysiological, and MRI characteristics of ADPSP were investigated. METHODS: Sixty three at risk members from five families were clinically evaluated. A diagnostic index was constructed for the study. Microsatellite genotypes were determined for chromosomes 2p, 14q, and 15q markers and multipoint linkage analyses were performed. Central motor conduction time studies (CMCT), somatosensory evoked potential (SSEP) measurement, and MRI of the brain and the total spinal cord were carried out in 16 patients from four families. RESULTS: The clinical core features of ADPSP were homogeneously expressed in all patients but some features were only found in some families and not in all the patients within the family. In two families non-progressive "congenital" ADPSP was seen in some affected members whereas adult onset progressive ADPSP was present in other affected family members. As a late symptom not previously described low backache was reported by 47%. Age at onset varied widely and there was a tendency for it to decline in successive generations in the families, suggesting anticipation. Genetic linkage analysis confined the ADPSP locus to chromosome 2p21-p24 in the five families. The lod scores obtained by multipoint linkage analysis were positive with a combined maximum lod score of Z=8.60. The neurophysiological studies only showed minor and insignificant prolongation of the central motor conduction time and further that peripheral conduction and integrity of the dorsal columns were mostly normal. Brain and the total spinal cord MRI did not disclose any significant abnormalities compared with controls. CONCLUSIONS: ADPSP linked to chromosome 2p21-p24 is a phenotypic heterogeneous disorder characterised by both interfamilial and intrafamilial variation. In some families the disease may be "pure" but the existence of "pure plus" families is suggested in others. The neurophysiological and neuroimaging investigations did not show any major abnormalities.

Adolescent↗

PubMed1998

Urodynamic evaluation of patients with autosomal dominant pure spastic paraplegia linked to chromosome 2p21-p24.

OBJECTIVES: There are at least three clinically indistinguishable but genetically different types of autosomal dominant pure spastic paraplegia (ADPSP). Lower urinary tract symptoms are often present but have not been described in a homogeneous patient population. In this study lower urinary tract symptoms, cystometrical, and neurophysiological characteristics are described in patients with ADPSP linked to chromosome 2p21-p24. METHODS: Lower urinary tract symptoms were recorded at an interview and according to a formalised questionnaire. Eleven patients were clinically evaluated and cystometry, measurements of the cutaneous perception threshold, bulbocavernosus reflex latency, and somatosensory evoked potentials (SSEPs) of the pudendal nerve were performed. RESULTS: All patients experienced urinary urgency or urge incontinence. Rectal urgency and sexual dysfunction were reported by most patients. The cystometrical findings showed a mixed pattern of bladder dysfunction. The SSEPs were normal in all but the bulbocavernosus reflex latency was significantly prolonged in seven patients and the cutaneous perception threshold was raised in five patients. CONCLUSIONS: Lower urinary tract symptoms and probably also bowel and sexual dysfunction in patients with ADPSP linked to chromosome 2p21-p24 are due to a combination of somatic and autonomic nervous system involvement which support the proposed multisystem affection in ADPSP linked to chromosome 2p21-p24.

Adult↗

PubMed1998

Adolescents' perceptions of caring in family, media, school, peer, and religious environments.

Adolescents were asked to select from two-word pairs the one that was emphasized more in their experiences with the environments of school, church, family, friends, or media. One of the word pairs was an indicator of caring, the other of justice. Analysis of responses of 87 adolescents indicated school was perceived as very low in caring compared to family, church, and friends.

Adolescent↗

PubMed1995

Hereditary haemochromatosis: a case of iron accumulation in the basal ganglia associated with a parkinsonian syndrome.

Hereditary haemochromatosis is characterised by excessive parenchymal iron deposition, particularly in the liver. Usually hereditary haemochromatosis is not associated with neurological symptoms and iron deposition in the brain has not previously been described as a pathological phenomenon. A patient is reported with hereditary haemochromatosis and a syndrome of dementia, dysarthria, a slowly progressive gait disturbance, imbalance, muscle weakness, rigidity, bradykinesia, tremor, ataxia, and dyssynergia. The findings on MRI of a large signal decrease in the basal ganglia, consistent with excessive iron accumulation, indicate a causal relation to the symptoms. Although the neurological symptoms did not improve in our patient, hereditary haemochromatosis should be considered in the differential diagnosis of parkinsonian syndromes, because complications of iron induced organ injury may be prevented by phlebotomy.

Basal Ganglia↗

PubMed1992

Relative bioavailability in man of noscapine administered in lozenges and mixture.

The bioavailability of noscapine base administered in lozenges in a dose of 100 mg to twelve healthy volunteers, in a study using an open balanced cross-over design, was compared with that of 100 mg of noscapine hydrochloride given perorally as a mixture. The bioavailability of noscapine after administration in lozenges was significantly higher than that after administration of the drug as a mixture. It is concluded that the lozenges containing noscapine base may be a valuable alternative to the conventional noscapine hydrochloride mixture.

Adult↗

PubMed1991

A method for histological preparation of undecalcified bone sections containing acrylic bone cement.

An improved and time reducing method is presented for the histological evaluation of bone containing polymethylmethacrylate (PMMA) bone cement. The undecalcified bone was embedded in epoxy resin and section of 50-100 microns thickness were produced using a commercially available cutting grinding system. The sections were stained with Stevenel's blue and van Gieson picrofuchsin or a modified hematoxylineosin. PMMA bone cement was not dissolved and remained enabling examination in situ of an intact cement bone interface and tissue reaction without decalcification.

Animals↗

PubMed1991

Chewing gum and lozenges as delivery systems for noscapine.

Chewing gum and lozenges were evaluated as delivery systems for noscapine with the aim of developing improved antitussive preparations. The formulations studied were prepared with both the water-soluble hydrochloride salt of noscapine and with the poorly soluble embonate salt and noscapine free base. The release characteristics of the preparations were evaluated both in vitro and in vivo, and their taste properties examined. Only the formulations containing noscapine base were without any appreciable taste. Chewing gum containing this compound showed, however, a low level of drug release both in vitro and in vivo and is therefore not a suitable dosage form. Only a lozenge formulation containing noscapine base fulfilled the requirements of taste acceptability and adequate release properties.

Chewing Gum↗

PubMed1991

Histological evaluation of cortical bone reaction to PMMA cement.

This study was designed to investigate histological changes in the tibia of adult mongrel dogs receiving PMMA bone cement in one tibial shaft and an inert filler, Bone wax, in the other. Sixteen dogs were used, 2 dogs were investigated at one week, 6 dogs at four weeks and 8 dogs at twelve weeks. It was shown in this study, that intramedullary implantation of PMMA bone cement leads to considerable impairment of bone remodelling. At each period of observation the index periosteal apposition/cortex thickness was lower on the cemented side; at 4 weeks an index of 0.42 (0.17-0.64) compared to 0.72 (0.42-0.91), and a 60-70 microns concentric fibrillar fibrous membrane was seen between cement and bone. On the Bone wax side few or no areas of fibrous tissue were detected at both 4 and 12 weeks; and when such tissue was present, islands of bone developing directly onto the wax was seen. The bone remodelling was impaired on the cemented side and limited to the outer half after 4 weeks.

Animals↗

PubMed1990

Bone growth into a revised porous-coated patellar implant.

A noncemented and clinically stable porous-coated patellar component (PCA) was removed from a patient after 11 months because of infection. It was sectioned and examined histologically in undecalcified, thin-ground sections. The bone ingrowth into the porous space was measured at eight levels. Each histologic section was quantified by a conventional point-counting method using a square grid. There was inhomogeneous, but extensive, bone ingrowth, often extending to the core of the patellar component, with direct contact between bone and porous coating without any interstitial fibrous membrane.

Adult↗

PubMed1989

A method for preparing and staining histological sections containing titanium implants for light microscopy.

An improved method for preparing and staining ground tissue-implant sections for light microscopy is presented. Undecalcified tissue blocks with titanium implants were dehydrated in an ascending series of ethanol and stained in toto with basic fuchsin. Specimens were infiltrated and embedded in methyl methacrylate and sections were prepared using a cutting-grinding-system. The polished surface was counterstained with light green or anilin blue. Light polymerizing resin was used as slide mounting medium and for mounting the coverglass. The sections obtained were 10-15 microns thick with tissue architecture which clearly differentiated structures at the tissue-implant interface. The method was very useful for computer assisted morphometric analysis.

Animals↗