Use of coisogenic host blastocysts for efficient establishment of germline chimeras with C57BL/6J ES cell lines.

Gene targeting in embryonic stem (ES) cells allows the production of mice with specified genetic mutations. Currently, germline-competent ES cell lines are available from only a limited number of mouse strains, and inappropriate ES cell/host blastocyst combinations often restrict the efficient production of gene-targeted mice. Here, we describe the derivation of C57BL/6J (B6) ES lines and compare the effectiveness of two host blastocyst donors, FVB/NJ (FVB) and the coisogenic strain C57BL/6-Tyr(c)-2J (c2J), for the production of germline chimeras. We found that when B6 ES cells were injected into c2J host blastocysts, a high rate of coat-color chimerism was detected, and germline transmission could be obtained with few blastocyst injections. In all but one case, highly chimeric mice transmitted to 100% of their offspring. The injection of B6 ES cells into FVB blastocysts produced some chimeric mice. However; the proportion of coat-color chimerism was low, with many more blastocyst injections required to generate chimeras capable of germline transmission. Our data support the use of the coisogenic albino host strain, c2J, for the generation of germline-competent chimeric mice when using B6 ES cells.

Regulation of the segmental swim-generating system by a pair of identified interneurons in the leech head ganglion.

1. The aim of this study was to identify neurons that modulate activity of segmental swim gating interneurons. We found a pair of bilaterally symmetrical interneurons, cells SE1, whose activity level directly influences three groups of segmental neurons associated with generating swimming in the medicinal leech. 2. The somata of cells SE1 are located on the dorsal surface of the subesophageal ganglion. Their axons extend most, if not the entire, length of the ventral nerve cord and appear to make identical connections with the same group of swim-generating neurons in all segmental ganglia. 3. Cells SE1 excite monosynaptically all segmental swim gating interneurons, cells 204, examined. The level of excitation in cell 204 is directly correlated with the firing frequency of cell SE1. In most quiescent preparations (when the preparation is not swimming) hyperpolarization of a single cell SE1 eliminates all excitatory synaptic input to cells 204. 4. Cells SE1 excite monosynaptically three swim oscillatory interneurons, cells 115, 28, and 208. The strength of the connection from cell SE1 to cell 115 is stronger than the connection from cell SE1 to either cells 28 or 208. The level of excitation in cell 115 is directly correlated with the firing frequency of cell SE1. In most quiescent preparations, hyperpolarization of a single cell SE1 eliminates all excitatory synaptic input to cell 115 but has only a minor effect on the level of activity in cells 208 and 28. 5. Due most likely to the strong and direct connections cells SE1 have with swim gating and oscillatory interneurons, brief stimulation of cell SE1 can elicit swimming. Swimming generally occurs within 1 s after stimulation of cell SE1. During swimming, the membrane potential of cell SE1 depolarizes by 2-5 mV, and its firing frequency increases. Brief depolarization of cell SE1 during swimming reliably shifts the phase of the swimming rhythm, whereas longer periods of depolarization increase both swim period and burst duration. 6. Excitatory motor neurons to the dorsal longitudinal muscles, cells 3, 5, and 7, are strongly excited by stimulation of cell SE1. The firing frequency of cell 3 is positively correlated with the firing frequency of cell SE1. 7. The results of this study indicate that cells SE1 can modulate the level of excitation in three groups of neurons associated with generating leech swimming.(ABSTRACT TRUNCATED AT 400 WORDS)

Perceived prestige and health careers recruitment.

Perceived occupational prestige is an important factor in career choice. The purpose of this study was to obtain prestige ratings of 13 allied health occupations and 13 general occupations for high school students, community college students (nonhealth majors), and community college health occupations students. The obtained ratings were compared with ratings of a combined group of health care providers. There was little agreement among the groups as to level of prestige. The high school rankings were the most disparate. Career exploration and outreach programs as part of recruitment efforts by health care institutions are suggested.

Readability and writing style analysis of selected allied health professional journals.

Using US Department of Defense text sampling procedures, nine allied health journals were analyzed for readability and selected writing style indices via Right Writer, a commercial software program. Two indices of readability were computed for each journal as were several indices of writing style. The computed readability ranged from 13.0 to 15.4, depending upon the journal in question. Two journals showed the highest levels of readability (15.4) compared to the other seven journals. The writing style analyses indicated generally normal ranges for the descriptive and jargon indices, but seven journals showed below recommended strength indices. Sentence structure analyses indicated a need to reduce sentence structure complexity. Implications for journal editors and authors are discussed.

Prestige: radiologic technologists rate themselves and other allied health professionals.

This study investigated radiologic technologists' (RTs) prestige ratings of 13 allied health professions and 13 general occupations selected from the original National Opinion Research Center (NORC) list. RTs ranked themselves fifth and on the whole tended to elevate the ratings of the allied health professions. There was a high degree of agreement between RTs' ratings and the NORC occupations data. Implications for the RT profession and for future research are noted.

Femoropopliteal bypass using autogenous vein and modified human umbilical vein. A comparative study.

This study is based on 223 consecutive femoro-popliteal and femorotibial bypass grafts performed between January 1978 and June 1985 at the Western General Hospital. Autogenous vein grafts demonstrated better 5 year patency rates (54%) than modified human umbilical vein (32%). The superiority of autogenous vein was even more marked when anastomoses were to below knee vessels: 56% compared with 26% at 5 years. Grafts anastomosed to the superficial femoral artery had similar long term patency to those anastomosed to the common femoral artery. When grafts were required for severe ischaemia, similar 5 year patency rates were achieved with autogenous vein (35%) and modified human umbilical vein (30%). The 5 year limb salvage rate in severe ischaemia was 72% for autogenous vein and 63% for modified human umbilical vein. The findings confirm that modified human umbilical vein is a satisfactory alternative when autogenous vein is not available.

Differential attitudes of Chinese students toward people with disabilities: a cross-cultural perspective.

The purpose of this study was to examine the attitudes of 338 Chinese secondary school students toward three major disability groups (people who are physically disabled, emotionally disturbed, and mentally retarded) using an adaptation of the American Scale of Attitudes toward Disabled Persons (SADP). We found that physically disabled persons were rated higher across the three subscales of the SADP compared to either emotionally disturbed and mentally retarded individuals, who were rated similarly low by the students. The lack of differentiation between the two mental handicapping conditions is at variance with contemporary western findings. The overall negative attitudes toward people with mental disabilities may have significant implications for community rehabilitation programming for this population.

Treatment of acute nontoxic megacolon during colonoscopy: tube placement versus simple decompression.

The study compares the efficacy of colonoscopic decompression versus decompression and tube placement in the treatment of Ogilvie's syndrome. Nine patients were treated with a single colonoscopic decompression which resulted in four recurrences. In contrast, there were no recurrences observed in 11 patients who underwent decompression and subsequent tube placement (p less than 0.05). There was no morbidity observed from either decompression or tube placement. Tube placement added less than 10 min of additional procedure time to the colonoscopy. The tube utilized in this study was an enteroclysis tube with sideholes cut in the distal 20 cm. The tube was easily inserted over a Teflon-coated flexible guide wire inserted through the colonoscope into the cecum following decompression. This study demonstrates that colonoscopic decompression followed by tube placement is the preferred treatment modality for acute nontoxic megacolon.

Stereotyping. Physical and occupational therapists characterize themselves and each other.

Physical therapists (n = 53) and occupational therapists (n = 53) appraised themselves and each other by selecting personal and job-based adjectives (54 pairs) on the Health Team Stereotype Scale. The PTs' self-appraisal differed statistically from the OTs' perception of PTs on 31 adjective pairs (57%). The OTs judged PTs as having fewer of the qualities PTs professed on 16 pairs. On 15 pairs, the OTs chose negative adjectives, whereas the PTs chose the positive. The OTs' self-assessment differed statistically from the PTs' perception of OTs on 24 pairs. The PTs perceived OTs as having fewer of the positive adjectives than did the OTs. The PTs' and OTs' self-assessments differed statistically on pairs such as Strong-Weak, Intelligent-Unintelligent, and Aggressive-Passive, with the PTs' mean scores being higher than the OTs'. Overall, the PTs' self-appraisal mean scores were higher than the OTs'. The extent of differences perceived by another profession may explain team conflict or team effectiveness.

Prestige of radiologic technologists: perception of two allied health professions.

Physical and Occupational Therapists in large urban hospitals rated the prestige of 13 allied health professions, generally hospital based. Radiologic Technologist was ranked 13th by PTs and 12th by OTs. PTs were more negative with 35% using ratings below "average," while OTs assigned 28%. Only 27% of the PTs used ratings above "average," while 33% of the OTs did so. Prestige scores derived for Radiologic Technologists placed them among nonprofessionals.