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E Mohr

Publications and source records attributed to E Mohr.

At least 73 records · Page 4Linked to original sources
PubMed1995

[Osteochondral lesions].

MRI has demonstrated high diagnostic value in the assessment of musculoskeletal disease. Pathological joint changes, especially in the osteochondral region, are an important orthopedic problem because the signs and symptoms are vague and unspecific. Therefore, in early disease their extent and severity are difficult to ascertain clinically. Early diagnosis and exact staging are recommended for sufficient therapeutic management. MR imaging has proved to be the method of choice in the evaluation of osteochondral lesions and helps to prevent late-stage disease and joint damage.

Cartilage, Articular↗
PubMed1995

Production of hybrid oxytocin/vasopressin precursors and accumulation of oxytocin precursors in the rough endoplasmic reticulum of rat magnocellular neurons.

Most magnocellular hypothalamic neurons synthesize the precursor for either vasopressin (AVP) or oxytocin (OT). The AVP precursor is cleaved to give AVP, AVP-associated neurophysin (AVP-NP) and a glycopeptide (GP), whereas the OT precursor gives OT and OT-NP. In Brattleboro rats a frame-shift mutation in the AVP-NP-encoding region of the gene prevents the secretion of AVP by the cells and, in most AVP neurons, AVP itself is virtually undetectable. A small number of magnocellular neurons in homozygous Brattleboro rats contain very large accumulations of peptide in distended saccules of rough endoplasmic reticulum (RER), and this peptide is immunoreactive for AVP and C-terminal OT-NP, but not for OT, AVP-NP or GP (Pow et al., 1992). We have now shown that this results from somatic non-homologous crossing over of the AVP and OT genes, resulting in the production of hybrid mRNA molecules with the 5'end of the AVP sequence and the 3' end of the OT sequence (AVP/OT transcripts). In most cases, the crossing over occurs within the highly homologous B exons (Mohr et al., 1994). In addition to the production of AVP/OT hybrid transcripts, polymerase chain reaction (PCR) amplification of mRNA from the hypothalami of homozygous rats also reveals OT/AVP hybrid transcripts, with 5' OT sequences and 3' AVP sequences. Furthermore, both types of hybrid transcript are not restricted to homozygous Brattleboro rats but can also be found in normal Long Evans animals. To date, we have not been able to locate cells in which the OT/AVP hybrids are produced; all the magnocellular neurons with hybrid peptide accumulations in the RER so far studied have been shown by immunocytochemistry to be of the AVP/OT type. In both normal and homozygous Brattleboro rats large accumulations of peptide do occur in the RER of OT-producing neurons but the peptide is immunoreactive for OT and OT-NP but not for AVP, AVP-NP or GP. Such cells increase in number 10-fold after injection of 20 micrograms estradiol daily for 7 days (Pow et al., 1991). Why this apparently normal gene product accumulates within the RER remains to be determined.

Aging↗
PubMed1994

Somatic nonhomologous crossing-over between neuropeptide genes in rat hypothalamic neurons.

Molecular biological and immunocytochemical data demonstrate nonhomologous crossing-over between the closely linked vasopressin (VP) and oxytocin (OT) genes in rat hypothalamic neuroendocrine neurons. Reverse transcription of hypothalamic total RNA from wild-type or homozygous Brattleboro aged rats combined with polymerase chain reaction (PCR) amplifications in the presence of appropriate 5' forward and 3' reverse primers deduced from the VP and OT cDNA sequences yielded PCR products that, upon cloning and sequencing, revealed several hybrid transcripts. They encode the N-terminal part of the VP precursor fused to the C-terminal part of the OT precursor (VP/OT transcripts) and vice versa (OT/VP transcripts). VP/OT hybrid precursor proteins have been identified immunocytochemically in enlarged cisternae of the rough endoplasmic reticulum, yet there is no evidence that the products can be secreted from affected cells. Recombination appears to be a rather frequent genetic event affecting about 0.06-0.1% of the rat vasopressinergic magnocellular neurons in aged rats.

Amino Acid Sequence↗
PubMed1994

Symptomatic relief from treatment-induced psychosis in Parkinson's disease: an open-label pilot study with remoxipride.

Current treatment strategies for levodopa-induced psychosis in Parkinson's disease have had limited success. Remoxipride, a selective D2 receptor antagonist, was administered in an open label pilot study to seven parkinsonian patients exhibiting thought disorder. Symptoms improved significantly in six patients after treatment durations of 1-6 months and cleared completely in two individuals. One patient (at age 90 the oldest in the group) could not tolerate the compound due to significant motor deterioration, and the drug had to be discontinued after 1 week. In all remaining patients, no motor complications appeared, and therapeutic effects of remoxipride continued for up to 3 months after treatment cessation and have lasted for 2 years now in one individual. Further study of this compound in the context of treatment-induced psychosis in Parkinson's disease appears to be warranted.

Aged↗
PubMed1994

Huntington's disease: pathogenesis, diagnosis and treatment.

This review of the clinical features of Huntington's disease incorporates recent developments in pathophysiology, preclinical diagnosis and treatment. Although the mechanism initiating and guiding the cell destruction in this illness is currently unknown, the excitatory neurotoxin and the energy metabolism models may provide a valuable direction for future research. Similarly, although the precise relation between the neuroanatomical damage in Huntington's disease and the functional disability is not clear, applications of recently developed neural connection models have implicated a number of important brain-behavior associations. Preclinical diagnostic procedures have evolved through successive iterations that have each contributed to increased reliability. New functional brain imaging techniques are sure to add to this promising domain in the future. Preclinical diagnosis has been stimulated by the recent isolation of the Huntington's gene which has also rekindled awareness of the importance of informed genetic counselling and the inherent ethical dilemmas in genetic testing. Treatment approaches to Huntington's disease have been confined to palliative care with secondary symptom management and psychotherapeutic support. Experimental therapeutic strategies for the illness itself have had a rather disappointing record to date. Further developments in NMDA antagonism and neural cell grafting may provide some hope for the future.

Adult↗
PubMed1994

Neurotransmitter replacement therapy in Alzheimer's disease.

The relative success of symptomatic attenuation of motor dysfunction in Parkinson's disease with dopaminomimetics has spurred interest in neurotransmitter replacement therapy for treating Alzheimer's disease. While cholinergic dysfunction has been linked to various clinical parameters in Alzheimer's disease, cholinergic replacement, including precursor therapy, administration of direct-acting agonists and inhibition of enzymatic degradation has had only very modest success. The inhibition of enzymatic degradation has perhaps shown the most interesting results to date. However, conclusions with respect to efficacy continue to be controversial. Discussion continues about whether or not single transmitter replacement for Alzheimer's disease is a viable treatment approach. Deficiencies in central noradrenergic, serotonergic, GABAergic and perhaps dopaminergic neural transmission may also play a critical role in some of the clinical manifestations of Alzheimer's disease. In addition, certain neuropeptides, in particular somatostatin, may be important in this context. Several series of clinical trials are currently attempting to address these issues. Given the complexities of the pathophysiology of Alzheimer's disease, symptomatic relief may require multiple transmitter replacement and necessitate more definitive intercessions at the molecular biological level.

Aged↗
PubMed1993

Assessment of intellectual function in dementing disorders: validity of WAIS-R short forms for patients with Alzheimer's, Huntington's, and Parkinson's disease.

While commonly administered in the neuropsychological assessment of dementia, the Wechsler Adult Intelligence Scale-Revised (WAIS-R) is excessively long (70-90 min) and difficult for many patients. The present study examined WAIS-R data from patients with clinically distinct dementing disorders, including those with Alzheimer's, Huntington's, and Parkinson's disease (N = 148). The profiles of performance of these three patient groups across subtests were remarkably similar, suggesting that the use of a short form would not result in the loss of clinically significant information. The validity of several published short forms was reviewed. Although all of these systematically over- or underestimated Full Scale IQ for these patients, after a scaling table revision the Kaufman (1990) form appears to provide an accurate estimate of IQ. The use of this short form is therefore recommended to minimize frustration and fatigue on the part of the patient, and to allow the inclusion of other tests critical to the evaluation of dementia within a single assessment session.

Aged↗
PubMed1993

[Comparative computerized tomography cephalometric and pharyngometric studies of patients with severe and mild sleep apnea, and in a control group].

116 males were examined. Of these, 52 belonged to a control group, whereas 40 had severe obstructive sleep apnoea (apnoea index > 20 + clinical symptoms) and 24 mild obstructive sleep apnoea (apnoea index 5-20 + clinical symptoms) (in the following, OSA signifies obstructive sleep apnoea). Cephalometry and planimetric examinations of the pharynx were performed in recumbent position with the head in neutral position and with shallow respiration. The narrowest passage of the pharynx was measured; other measured sites were the areas of the nasopharynx, oropharynx (at the level of the tip of the palatine uvula) and of the hypopharynx (at the level of the base of the tongue). The sum of all the measured cross-sections was obtained. The cephalogram was evaluated to obtain the length and thickness of the soft palate, the distance between the mandible and hyoid bone, the posterior airspace (PAS), the nuchal subcutaneous fatty tissue at the level of the spine of the second cervical vertebra (also known as axis), the thickness of the posterior pharyngeal wall at the level of the second cervical vertebra, or axis, and the angles between the sella, nasion and superior maxilla and between the sella, nasion and mandible (SNA and SNB, respectively).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Statistical analysis of the incidence of positives in the examination of parasitological specimens.

Results of the examination of 2,000 parasitological specimens were analyzed for differences between results obtained by a technologist working in parasitology only and those obtained by general microbiologists who were also performing other laboratory work. The relative share of specimens determined to be positive by the specialist was approximately twice as high as the relative share determined by the general microbiologists.

California↗
PubMed1992

Heterogeneity in Alzheimer's disease: progression rate segregated by distinct neuropsychological and cerebral metabolic profiles.

In an attempt to define possible subgroups of Alzheimer's disease, 21 patients satisfying current clinical diagnostic criteria for this disorder were divided on the basis of progression rates of symptoms. Thirteen patients with relatively rapid intellectual deterioration did not differ from eight patients showing slow progression with respect to global intellectual performance, sex, or age at onset of symptoms. Neuropsychological testing revealed that although the two groups were indistinguishable in verbal or visuospatial functions associated with the parietotemporal cortex, the more rapidly deteriorating group had significantly greater impairment in executive functions attributed to the frontal lobe. PET scans showed equivalent reductions in glucose metabolism in the parietotemporal cortex, but patients with relatively fast progression had significantly greater hypometabolism frontally. These results suggest an association between relatively severe frontal lobe involvement and a rapid clinical course that might have important implications for the development of treatment strategies for patients with Alzheimer's disease.

Aged↗