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R J Morris

Publications and source records attributed to R J Morris.

At least 109 records · Page 6Linked to original sources
PubMed1994

Slowly cycling (label-retaining) epidermal cells behave like clonogenic stem cells in vitro.

Slowly cycling label-retaining epidermal cells were identified by light microscopic autoradiography in the dorsal epidermis and hair follicles of adult mice 8-10 weeks after twice daily injection of [3H]dT on days three through five after birth. Pulse-labelled epidermal cells were identified in the epidermis and hair follicles of 7-8 week old mice 1 h after a single injection of [3H]dT at 8.00 a.m. For mice of both groups, epidermal cells including those from the hair follicles were harvested by trypsinization and were cultured from low density on feeder layers of irradiated Swiss mouse 3T3. On days 2, 4, 5, 7, 10 and 12, the cultures were fixed and processed for light microscopic autoradiography, and the distribution of labelled nuclei was quantified. On day 2 of culture, both label-retaining cells (LRC) and pulse labelled cells (PLC) were found primarily as single cells. After five days, LRC were found as pairs and clusters having silver grain counts consistent with their division. In contrast, PLC remained primarily as single cells. These results suggest that LRC may divide to form colonies (are clonogenic) whereas PLC are rarely clonogenic. The significance of this experiment is that it suggests that the LRC may not only be persistent in the epidermis, but that they may also be cells with relatively greater proliferative potential than the PLC and are thus likely to be stem cells.

Aging↗
PubMed1994

The perception of speech sounds recorded within the uterus of a pregnant sheep.

The intelligibility of speech stimuli recorded within the uterus of a pregnant sheep was determined perceptually using a group of untrained judges. The intrauterine sound environment of the ewe was intended to simulate that of a pregnant woman. Two separate lists, one of meaningful and one of nonmeaningful speech stimuli, were delivered through a loudspeaker to the side of the ewe and were simultaneously recorded with an air microphone located 15 cm from the flank and with a hydrophone previously sutured to the neck of the fetus. Perceptual test tapes generated from these recordings were played to 102 judges. The intelligibility of the phonemes recorded in the air was significantly greater than the intelligibility of phonemes recorded from the uterus. A male talker's voice was more intelligible than a female talker's voice when recorded from within the uterus, but not so when recorded in the air. An analysis of the feature information transmission from recordings inside and outside the uterus revealed that voicing information is better transmitted in utero than place or manner information.

Animals↗
PubMed1994

Superior oblique tendon lengthening for acquired superior oblique overactions.

Two patients who presented with compensatory head postures and diplopia are described. They both had marked unilateral superior oblique overaction, in one patient due to a large, incomitant skew deviation. Each underwent a superior oblique tendon lengthening procedure using a segment of silicone 240 retinal band as an expander, in combination with a contralateral superior rectus recession. Both achieved an excellent result with an improvement of the compensatory head posture and an increase in the field of binocular single vision. This surgical procedure is proposed as an option in the management of superior oblique overaction, including certain cases of skew deviation.

Accidental Falls↗
PubMed1994

Age-related differences in speech intensity among adult females.

Two groups of women, one aged 20-35 years and the other aged 75 years and older, read the 'Rainbow Passage' and produced the vowel/a/at minimum, conversational, and maximum intensity levels. The results indicate that the two groups did not exhibit significant differences in speech intensity for the reading passage or the conversational level vowel productions. On the other hand, the older women exhibited significantly higher minimum and significantly lower maximum intensity vowels than the younger women.

Adult↗
PubMed1994

The mode of anchorage to the cell surface determines both the function and the membrane location of Thy-1 glycoprotein.

The surface glycoprotein, Thy-1, when expressed by transfection in NG115/401L neural cells, inhibits their neurite outgrowth over astrocytes. We have investigated the role of the glycosylphosphatidylinositol anchor of Thy-1 in this inhibition. Hybrid molecules, in which the lipid anchor was replaced by polypeptide transmembrane domains, were expressed by transfection. Lines expressing Thy-1 with the transmembrane and full cytoplasmic domains of NCAM-140, or with the transmembrane and truncated cytoplasmic domain of CD8, were not inhibited in their ability to extend neurites over astrocytes. Truncation of the cytoplasmic domain of NCAM-140 to just two amino acids, however, produced a transmembrane form of Thy-1 that, when expressed at high levels, inhibited neurite outgrowth. All forms of Thy-1 were concentrated in clusters that occurred primarily on fine filopodia. In double transfectants expressing normal Thy-1 and Thy-1 with the full NCAM cytoplasmic tail, the clusters of each form were separate, with no instances of the transmembrane form being found within the clusters of lipid-anchored Thy-1. Thy-1 with the two-amino-acid cytoplasmic domain of NCAM also occurred in clusters separate from those occupied by lipid-anchored Thy-1, but substantial 'invasion' of the clusters of normal Thy-1 by this transmembrane construct occurred. We suggest that the ability of this hybrid protein to enter the lipid-anchored clusters enables it to activate the signalling pathways that normal Thy-1 uses. Thus the membrane anchor, in targetting Thy-1 to different microdomains on the cell surface, determines its ability to inhibit neurite outgrowth on astrocytes.

Amino Acid Sequence↗
PubMed1994

Phenotypic variation in acrocephalosyndactyly syndromes: unusual findings in patient with features of Apert and Saethre-Chotzen syndromes.

The acrocephalosyndactyly syndromes have presented diagnostic challenges because of overlap in their clinical manifestations. We present a patient with features most suggestive of Apert syndrome, but with a pattern of syndactyly not previously described. In contrast to the complex syndactyly reported as a universal feature of this syndrome, this patient shows close to total simple syndactyly of the index through ring fingers of each hand. Differential diagnoses are discussed. Because the features are reminiscent of Apert syndrome, we suggest that a new classification of hand morphology should be added to include the pattern described here.

Acrocephalosyndactylia↗
PubMed1993

Drowning.

Explore the source record for details and available documents.

Anaphylaxis↗
PubMed1993

Urokinase-type plasminogen activator expression by neurons and oligodendrocytes during process outgrowth in developing rat brain.

The expression of tissue- and urokinase-type plasminogen activators has been studied in developing cerebellum, hippocampus, cerebral cortex, olfactory bulb and olfactory mucosa of the rat by in situ hybridization. All identifiable neurons express urokinase mRNA from an early stage in their development, and this expression appears to coincide with the onset of axogenesis. For cerebellar granule cells, both axonal growth and urokinase expression are initiated before they migrate from the external granule layer; for the majority of neocortical neurons, however, both processes are commenced after the cells have migrated to the cortical plate. Neurons continue to express this protease in the adult. The large projection neurons exhibit the highest levels of message, the smaller interneurons having much lower levels except for hippocampal granule cells, which have notably high levels of expression. Glial cells generally do not express urokinase message, except for transient expression by oligodendrocytes in developing fibre tracts during the period of myelination. Thus for both neurons and oligodendrocytes, the onset of urokinase-type plasminogen activator expression coincides with their initiation of major process outgrowth, although neurons maintain this expression in the adult, possibly to retain a degree of synaptic plasticity. In contrast, although high levels of message for the related protease, tissue plasminogen activator, are found in the embryonic floor plate, in postnatal brain it is abundantly expressed only by ventricular ependymal cells and by cells in connective tissue surrounding the olfactory nerve.

Animals↗
PubMed1993

Association of protein kinase C activation with induction of ornithine decarboxylase in murine but not human keratinocyte cultures.

The goal of this study was to compare the response of mouse epidermal keratinocytes (MEKs) and human epidermal keratinocytes (HEKs) to 12-O-tetradecanoylphorbol-13-acetate (TPA) with respect to the activation and downregulation of protein kinase C (PKC), the expression of c-jun and c-fos, and the expression and induction of ornithine decarboxylase (ODC) activity. Keratinocytes from adult CD-1 mice and from discarded adult human skin were grown in primary culture in a high-calcium serum-free medium that supported proliferation and differentiation. Immunoblotting of freshly isolated and cultured MEKs and HEKs for isozymes of protein kinase C revealed that fresh HEKs contained PKC alpha, PKC beta, and PKC delta; no PKC gamma, PKC epsilon, or PKC zeta were detected. In fresh MEKs, PKC alpha, PKC beta, PKC delta, and PKC zeta were observed, but not PKC gamma or PKC epsilon. After 2 wk in culture, the isozyme profiles of MEKs and HEKs were similar except that PKC gamma was noticeably present in HEK cultures. Activation of partially purified total PKC by TPA was similar in freshly isolated and cultured MEKs and HEKs, indicating that the two species were similar in this regard and that 2 wk of culture did not alter this characteristic. When MEK and HEK cultures were treated with TPA for 3 h, less than 30% of the control level of PKC activity was detected, indicating that TPA-induced downregulation of PKC was similar in MEKs and HEKs. After treatment with TPA, MEK cultures produced a large induction of both c-jun and c-fos mRNA by 60 min, as determined by northern blot analysis, and a large induction of ODC mRNA and enzyme activity by 6 h. TPA treatment of cultured HEKs, however, did not induce ODC activity; in fact, less activity, compared with that of control cultures, was observed. Northern blot analysis also revealed no increase in c-jun, c-fos, and ODC mRNA in HEKs. However, c-jun and c-fos mRNA and both ODC mRNA and enzyme activity were induced in HEKs fed growth factors after several days of deprivation. This suggests that the lack of ODC induction by TPA in HEKs is probably due to species differences in downstream steps in PKC signal transduction.

Adult↗
PubMed1993

Fusion after surgical alignment of longstanding strabismus in adults.

BACKGROUND: Fusion and the development of the monofixation syndrome are well recognized after surgical alignment of congenital esotropia to within 8 delta of orthotropia. However, in adults with longstanding strabismus and a history of congenital esotropia who are not surgically aligned within the first few years of life, the prognosis for the development of fusion is believed to be poor. METHODS AND RESULTS: Twenty-four adults, 12 with a history of congenital esotropia (onset before 6 months age), 1 of congenital exotropia, and 11 with the onset of esotropia between 6 months and 2 years, were included in this study. All patients had longstanding strabismus, and none had been surgically aligned within the first 2 years of life. No patient had visual acuity worse than 20/30 in the worse eye. Preoperatively, no patient demonstrated fusion with the red glass test, Worth four-dot, or Titmus test. Postoperatively, all were aligned to within 8 delta of orthotropia, and all demonstrated peripheral fusion with the Worth four-dot at near. Twelve patients (50%), 8 of whom were in the congenital group, achieved stereopsis of 200 seconds of arc or better using the Titmus stereo test. CONCLUSION: These findings suggest that surgery in this group of patients not only eliminates the ocular alignment deformity but can confer the functional benefits of fusion and increased field of binocular vision.

Adolescent↗
PubMed1993

Phonational profiles of female professional singers and nonsingers.

Measures of the SFF, vocal intensity, phonational range, and habitual pitch level are reported for 39 professional singer and 39 nonsinger females, who were divided into three age groups (young, middle, and old age), with the professionals further divided into sopranos and altos. Each read the "Rainbow Passage" and spoke extemporaneously, from which measures of the SFF and vocal intensity were calculated; phonational range and habitual pitch levels were also determined. No significant differences were noted between the reading and speaking tasks. The SFF and intensity levels were significantly higher for the professionals in comparison to the nonsingers, but only for certain age groups. Moreover, whereas the nonsinger SFF levels varied significantly as a function of age, those for the professional singers did not. Although trends occurred, no significant differences were found for the mean phonational range or habitual pitch levels when the professionals and nonsingers were compared.

Adult↗
PubMed1993

Day case management in adjustable suture squint surgery.

Day case adjustable suture squint surgery is limited by patient cooperation in the early post-operative period. Nausea is common and may be exacerbated by adjustment. To facilitate early adjustment, in 37 consecutive patients anaesthesia was induced with propofol and the airway maintained with a laryngeal mask. Before and after adjustment patients recorded their level of nausea on a visual analogue scale (1 = no nausea, 10 = vomiting). The mean age of the group was 31.9 years with 20 men and 17 women. Adjustment was performed at a mean time of 4.9 hours after surgery. On the analogue scale of nausea the mean score was 1.54 pre-adjustment and 1.73 post-adjustment. Only 1 patient was given a post-operative anti-emetic. All patients were sufficiently alert to adjust without difficulty and were discharged the same day. The use of a laryngeal mask and induction of anaesthesia with propofol in adjustable suture squint surgery facilitates early adjustment and thus day case management.

Adolescent↗
PubMed1993

Administration errors with a conventional metered dose inhaler versus a novel breath actuated device.

Metered dose inhalers are difficult for patients to use. A device that eliminates coordination and timing of actuation may simplify the use of metered dose inhalers. This trial compared (1) number of errors made and (2) specific errors made between the conventional press and breathe metered dose inhaler (MDI) and the novel breath actuated Autohaler inhalation device in 24 subjects. We studied the use of each device in 12 patients trained and experienced in using an MDI and in 12 volunteers who had never been exposed to any inhalation device. We observed that even experienced patients continue to have difficulty with the coordination and timing of metered dose inhalers. The volunteer group had equal difficulty with both devices but it appeared that it was easier for them to learn how to use the breath actuated device than the MDI.

Administration, Inhalation↗
PubMed1992

Utility of immunohistochemistry in distinguishing ovarian sertoli-stromal cell tumors from carcinosarcomas.

Poorly differentiated Sertoli-stromal cell tumors and carcinosarcomas of the ovary both show biphasic epithelial and stromal patterns and may both show heterologous stromal elements, presenting a difficult diagnosis. We studied the immunohistochemical profile of Sertoli cell differentiation in human testes and applied these findings to the ovarian tumors. Eleven Sertoli-stromal cell tumors, six carcinosarcomas of the ovary, and 11 testes (six fetal, one infant, and four adult) were studied using antibodies to cytokeratin AE1:AE3 (AE1:3), cytokeratin CAM 5.2 (CAM), epithelial membrane antigen (EMA), vimentin, desmin, muscle-specific actin (MSA), S-100 protein (S-100), CA 19-9, CA 125, carcinoembryonic antigen monoclonal (CEA-M), carcinoembryonic antigen polyclonal (CEA-P), and placental alkaline phosphatase (PLAP). In the fetal testes, immature gonadal stroma and sex cord areas stained with vimentin (six of six cases), AE1:3 (five of six cases), and CAM (six of six cases). Sertoli cells in immature gonadal stroma areas, sex cords, and seminiferous tubules of normal fetal, infant, or adult testes never showed immunoreactivity for EMA, S-100, CA 19-9, CA 125, CEA-M, CEA-P, or PLAP. All Sertoli-stromal cell tumors stained with AE1:3 and CAM in areas of Sertoli cell differentiation (11 of 11 cases) but did not stain with EMA, PLAP, CEA-P, CEA-M, CA 19-9, CA 125, or S-100 (none of 11 cases). Carcinosarcomas expressed AE1:3 and CAM in all epithelial areas (six of six cases) and most stromal areas (five of six cases). Carcinomatous areas of carcinosarcoma also showed immunoreactivity for EMA (six of six cases), CA 125 (two of six cases), PLAP (two of six cases), CEA-P (two of six cases), and CEA-M (one of six cases), while stromal areas of carcinosarcoma expressed EMA (four of six cases) and S-100 (four of six cases). Heterologous stromal elements were present in three of 11 Sertoli-stromal cell tumors (two showed skeletal muscle and one showed both skeletal muscle and cartilage differentiation) and in four of six carcinosarcomas (one skeletal muscle, one cartilage, and two cartilage and skeletal muscle). All skeletal muscle heterologous elements expressed desmin, vimentin, and MSA. The heterologous cartilage in carcinosarcoma stained with S-100 (three of three), while the one case of heterologous cartilage in Sertoli-stromal cell tumor did not. These results suggest that ovarian Sertoli-stromal cell tumor can be distinguished from carcinosarcoma by the absence of staining for EMA, PLAP, CEA, CA 125, or CA 19-9 in epithelial areas of Sertoli-stromal cell tumor.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗