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R B Phillips

Publications and source records attributed to R B Phillips.

At least 37 records · Page 2Linked to original sources
PubMed1997

Physical localization and characterization of the BglI element in the genomes of Atlantic salmon (Salmo salar L.) and brown trout (S. trutta L.).

This work describes chromosomal localization, fine physical mapping, and population variation of the BglI element in the genome of Atlantic salmon (Salmo salar L.) and a similar sequence in the genome of brown trout (S. trutta L.). Results from a variety of complementary approaches, clearly demonstrate that the BglI element does not occur as a satellite-like repetitive DNA in these species but is part of the rDNA cistron as suggested by Goodier and Davidson (1993). Coincident hybridization of BglI clones with rDNA loci in both single and double-probe fluorescence in situ hybridization (FISH) experiments demonstrated physical linkage between the BglI element and rDNA loci. Fine physical mapping by Southern analysis and PCR amplification showed the BglI element to be located approximately 1.6 kb upstream of the 18S gene. The BglI element was used to screen for population-specific markers by Southern analysis. Population-specific banding patterns were only observed in brown trout, allowing identification of individual populations of this species. Sequence comparisons revealed sequences similar to the BglI element present in the rDNA cistron of other salmonids. This result suggests the presence of this sequence in the genome of the salmonid tetraploid ancestor.

Animals↗
PubMed1997

An AluI fragment isolated from lake trout (Salvelinus namaycush), maps to the intergenic spacer region of the rDNA cistron.

The relationship between a 217-bp AluI fragment (SnAluI-33c) from lake trout (Salvelinus namaycush) which hybridizes to the nucleolar organizer regions (NORs) and the ribosomal RNA genes was examined by Southern analysis and comparative hybridization. Restriction enzymes with recognition sites mapped in the lake trout rDNA cistron were used to digest genomic DNA into fragments of predetermined size. Comparison of the hybridization pattern of SnAluI-33c with those of two rDNA-specific probes placed this fragment within the intergenic spacer region of the rDNA cistron, approximately 3 kb upstream (5') of the 18S gene. This finding is consistent with in situ hybridization experiments showing hybridization of this fragment to sites of rDNA [Reed, K.M. and Phillips, R.B., Cytogenet. Cell Genet. 70 (1995) 104-107]. Based on cross hybridization and sequence comparisons, homologous sequences are present in other salmonid species.

Animals↗
PubMed1997

Polymorphism of the nucleolus organizer region (NOR) on the putative sex chromosomes of Arctic char (Salvelinus alpinus) is not sex related.

Polymorphism of the nucleolus organizer region (NOR) on the putative sex chromosomes of Arctic char (Salvelinus alpinus) was examined using conventional cytogenetic and molecular techniques. Variation was observed in the number, size and position of rDNA loci on the sex pair. Fluorescence in situ hybridization (FISH) analyses showed that the sex chromosomes of Arctic char lack the repetitive DNA sequences (Mbol/BglII family) that are a prominent feature of the sex chromosomes of lake trout (S. namaycush). Southern analyses of genomic DNAs using an rDNA fragment as probe revealed extensive restriction fragment length polymorphism (RFLP) variation among individuals. Despite the presence of variation in all aspects of this rDNA locus, no sex-specific differences were detected. Repetitive DNAs (multicopy rDNA as in Arctic char or tandem repetitive DNA as in lake trout) appear to play important but different roles in the evolution of the sex chromosomes in these species.

Animals↗
PubMed1997

Characteristics of two salmonid repetitive DNA families in rainbow trout, Oncorhynchus mykiss.

DNA sequence and genomic location of two repetitive DNA families in rainbow trout (Oncorhynchus mykiss) were investigated to develop molecular markers for chromosome identification. DNA fragments with sequences similar to the tandem and interspersed elements described in other salmonids were isolated. One clone showed differential hybridization to 12 pairs of chromosomes and should be a useful marker for physical mapping.

Animals↗
PubMed1997

Comparison of entrance requirements for health care professions.

OBJECTIVE: To compare U.S. chiropractic college admissions requirements with those of allopathy, osteopathy, optometry, podiatry and dentistry. DESIGN: Survey. PARTICIPANTS: The schools that participated in the comparison were selected based on their geographic location within the United States. The number of schools selected were 16 chiropractic college, 17 allopathic colleges, 16 osteopathic colleges, 16 optometric colleges, 7 podiatric colleges and 15 dental colleges. MAIN OUTCOME MEASURES: Information collected from the individual schools included: (a) minimum number of undergraduate semester hours (toward a bachelor's degree) that are required on entrance; (b) actual percentage of applicants with a 4-yr bachelor's degree on entrance; (c) minimum GPA required on entrance and (d) actual average GPA of applicants on entrance. RESULTS: Averages were computed for each outcome. Overall, allopathic averages were highest and chiropractic averages were lowest for each of the four outcome measures, with the other programs scoring at varying points in between. CONCLUSION: Successful completion of preprofessional requirements may be an indicator for success within a rigorous professional curriculum. These data reflect overall differences between health-care professions on a very few entrance criteria. Further investigation is needed to understand the long-term impact of these differences as well as the possible economic or political factors that may be influencing these results.

Chiropractic↗
PubMed1996

A new method for detecting nucleolus organizer regions in fish chromosomes using denaturation and propidium iodide staining.

A rapid method for detecting nucleolus organizer regions (NORs) in fish chromosomes based on thermal denaturation and staining with propidium iodide is described. Under epifluorescence, the NORs of 15 fish species from six families could be detected. This protocol differentiates constitutive heterochromatin in mammalian and avian chromosomes, and in some cases, heterochromatic blocks in fish chromosomes. The staining of NORs of fish chromosomes with propidium iodide following denaturation with formalin is likely the result of differential denaturation of the rDNA due to the thermal characteristics of AT- and GC-rich domains of the rDNA cistron. This technique provides a new useful marker for descriptive fish cytogenetic studies.

Animals↗
PubMed1995

Phylogenetic analysis of Pacific salmon (genus Oncorhynchus) based on mitochondrial DNA sequence data.

Previous phylogenetic analyses of the fishes belonging to the genus Oncorhynchus based on mitochondrial DNA data have produced conflicting trees. This is especially true with respect to the relationships among the three most derived Pacific salmon species, the pink salmon (Oncorhynchus gorbuscha), sockeye salmon (Oncorhynchus nerka), and chum salmon (Oncorhynchus keta). Smith (Syst. Biol. 41(1): 41-57, 1992) suggested that introgression in opposite directions on either side of the Pacific ocean may account for some of the conflicting data. The ATPase 6 and ND3 mitochondrial genes were sequenced from Asian and North American representatives of several species of Pacific salmon and the aligned sequences were analyzed along with other data on these genes. Analysis of the ATPase 6 and ND3 sequence data and RFLP data gives strong support for a sister relationship between pink salmon and chum salmon.

Adenosine Triphosphatases↗
PubMed1995

Molecular characterization and cytogenetic analysis of highly repeated DNAs of lake trout, Salvelinus namaycush.

The chromosomes of lake trout (Salvelinus namaycush) contain a considerable amount of heterochromatin located at the centromeres and/or telomeres of several chromosomes, including a sex-specific block located distally on the X chromosome. In order to investigate further the repetitive DNAs of lake trout, genomic DNA from a female was size fractionated (<600 bp) with the restriction endonuclease AluI and fragments were cloned into the bacteriophage M13. A total of 42 clones were isolated. Relative copy number of individual inserts within the lake trout genome was estimated by Southern analysis. Twelve clones were determined to be highly repetitive and were chosen for further investigation. Inserts of these clones contained sequences similar to the AluI/RsaI, EcoRI/DraI, DraI/BstEII, and MboI/BglII families reported from Arctic char (Salvelinus alpinus). The chromosomal location of several of these fragments was determined in lake trout by fluorescence in situ hybridization (FISH). Two related AluI/RsaI sequences (Type A, approximately 140 bp, and Type B,approximately 120 bp) showed differential hybridization. Type A hybridized to the centromeres of all metacentric as well as several acrocentric chromosomes. Type B hybridized to the centromeres of most acrocentric chromosomes. A sequence with homology to the EcoRI/DraI family hybridized to the centromeres of several acrocentric chromosomes. Sequences with partial similarity to the DraI/BstEII family hybridized to the major rDNA sites (nucleolar organizer regions, NORs) and several minor telomeric sites. The interstitial and telomeric heterochromatin of lake trout, including that of the X chromosome, appears to comprise sequences belonging to the MboI/BglII family.

Animals↗
PubMed1995

Microdissection of the Y chromosome and fluorescence in situ hybridization analysis of the sex chromosomes of lake trout, Salvelinus namaycush.

Lake trout, Salvelinus namaycush, is one of the few salmonids with morphologically differentiated sex chromosomes. Genetic analysis suggested that the sex-determining region of this species lies on the short arm of the Y chromosome. The differential arm of the Y chromosome was microdissected and the resulting DNA amplified in a sequence-independent manner. Amplified DNA was biotin labeled as a probe for fluorescence in situ hybridization (FISH). Strong hybridization signals were seen covering defined regions of both the Y and X chromosomes. Homeologous chromosomes of the ancestrally tetraploid genome were not identified by FISH with the Y probe, indicating diploidization of this region of the genome.

Animals↗
PubMed1995

Hypervariability of ribosomal DNA at multiple chromosomal sites in lake trout (Salvelinus namaycush).

Variation in the intergenic spacer (IGS) of the ribosomal DNA (rDNA) of lake trout (Salvelinus namaycush) was examined. Digestion of genomic DNA with restriction enzymes showed that almost every individual had a unique combination of length variants with most of this variation occurring within rather than between populations. Sequence analysis of a 2.3 kilobase (kb) EcoRI-DraI fragment spanning the 3' end of the 28S coding region and approximately 1.8 kb of the IGS revealed two blocks of repetitive DNA. Putative transcriptional termination sites were found approximately 220 bases (b) downstream from the end of the 28S coding region. Comparison of the 2.3-kb fragments with two longer (3.1 kb) fragments showed that the major difference in length resulted from variation in the number of short (89 b) repeats located 3' to the putative terminator. Repeat units within a single nucleolus organizer region (NOR) appeared relatively homogeneous and genetic analysis found variants to be stably inherited. A comparison of the number of spacer-length variants with the number of NORs found that the number of length variants per individual was always less than the number of NORs. Examination of spacer variants in five populations showed that populations with more NORs had more spacer variants, indicating that variants are present at different rDNA sites on nonhomologous chromosomes.

Animals↗
PubMed1994

A prospective randomized three-week trial of spinal manipulation, transcutaneous muscle stimulation, massage and corset in the treatment of subacute low back pain.

STUDY DESIGN: A randomized prospective trial of manipulation, massage, corset and transcutaneous muscle stimulation (TMS) was conducted in patients with subacute low back pain. OBJECTIVES: The authors determined the relative efficacy of chiropractic treatment to massage, corset, and TMS. SUMMARY OF BACKGROUND DATA: Although all of these treatments are used for subacute low back pain treatment, there have been few comparative trials using objective outcome criteria. Patients were enrolled for a period of 3 weeks. They were evaluated once a week by questionnaires, visual analog scale, range of motion, maximum voluntary extension effort, straight leg raising and Biering-Sorensen fatigue test. The dropout rate was highest in the muscle stimulation and corset groups and lowest in the manipulation group. Rates of full compliance did not differ significantly across treatments. A measure of patient confidence was greatest in the manipulation group. RESULTS: After 3 weeks, the manipulation group scored the greatest improvements in flexion and pain while the massage group had the best extension effort and fatigue time, and the muscle stimulation group the best extension. CONCLUSION: None of the changes in physical outcome measures (range of motion, fatigue, strength or pain) were significantly different between any of the groups.

Adult↗
PubMed1994

Minimal intraspecific variation in the sequence of the transcribed spacer regions of the ribosomal DNA of lake trout (Salvelinus namaycush).

Intraspecific variation in the sequence of the transcribed spacer regions of the ribosomal DNA (rDNA) in lake trout was examined by restriction mapping and sequencing of these regions amplified by the polymerase chain reaction. The length of the first internal transcribed spacer region (ITS-1) was 566 bases and the second internal transcribed spacer region (ITS-2) was 368 bases in lake trout. When the 1.4-kb region including the ITS-1, the 5.8S coding region, and the ITS-2 was amplified from 12 individuals from four populations and digested with eight different enzymes only one intraindividual polymorphism was found that occurred in each population. When the amplified ITS-1 region was sequenced from an additional 10 individuals from five populations, no interindividual variation was found in the sequence. A 6-kb portion of the rDNA repeat unit including 1.6 kb of the 18S coding region, the 5' external spacer region (5' ETS), and part of the adjacent intergenic spacer was cloned and a restriction map was prepared for these regions in lake trout. No intraspecific variation was found in the region adjacent to the 18S rDNA, which includes the 5' ETS, although intraspecific and intraindividual length variation was found in the intergenic spacer region 3-6 kb from the 18S. Sequencing of a 609-b segment of the 5' ETS adjacent to the 18S coding region revealed the presence of two 41-b repeats. The 198-b sequence between the repeats had some similarity to the 18S coding region of other fishes. Primers were designed for amplification of 559 b of the 5' ETS using the polymerase chain reaction.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Origins of the LACC, 1901-1922.

The Los Angeles College of Chiropractic (LACC) can trace its history from D. D. Palmer through Thomas H. Storey, D.C. to Charles A. Cale, D.C., N.D., the LACC's founder. The formation and early history of the College is intimately intertwined with the naturopathic movement and to a lesser extent the osteopathic profession in southern California during the first two decades of this century. Although the school would eventually become the largest producer of chiropractors in the densest chiropractic jurisdiction in the world, its early survival was not always certain, and its later status as a bellwether for the rest of the profession was not yet in evidence. Organized by Charles Cale in 1910 and chartered in 1911, the school would suspend operations for several years (1914-6) while Charles and Linnie Cale acquired osteopathic credentials. The school's rebirth in 1916 marked the beginning of the final push for the initiative act of 1922 that licensed chiropractors and ended some of the most intensive legal persecutions by organized medicine that chiropractors would ever experience. This initial phase of LACC's history (through 1922) set the stage for at least 12 subsequent mergers and reorganizations to form today's LACC. The College would later lead the state's and the profession's efforts to broaden and deepen the chiropractic curriculum during the middle ages of chiropractic.

Chiropractic↗
PubMed1992

Evolutionary relationships of the salmonid fish genus Salvelinus inferred from DNA sequences of the first internal transcribed spacer (ITS 1) of ribosomal DNA.

DNA sequences of the ribosomal DNA (rDNA) first internal transcribed spacer region (ITS 1) of six species of the salmonid fish genus Salvelinus (alpinus, malma, confluentus, leucomaenis, fontinalis, and namaycush) and the closely related species Hucho perryi were determined. Phylogenetic analysis of the aligned sequences by both phenetic and cladistic methods with H. perryi as an outgroup generated one best topology which pairs S. alpinus with S. malma as the most recently derived species, and pairs S. confluentus with S. leucomaenis. Three other possible topologies favor the pairing of S. namaycush and S. fontinalis, with one tree placing them on separate branches, and vary the branching order of the interior groups. These results agree with previous studies based on comparisons of morphologies, isozymes, karyotypes, and restriction sites showing a close genetic relationship and possible hybridization between the members of this genus.

Animals↗
PubMed1992

The descriptive profile of low back pain patients of field practicing chiropractors contrasted with those treated in the clinics of west coast chiropractic colleges.

OBJECTIVE: To compare the demographic and clinical characteristics of low back pain patients from chiropractic college clinics and private practice settings on the west coast of the United States. DESIGN AND SETTING: A survey analysis of consecutive new patients in a specified time frame from multiple private office settings contrasted with a previous survey of consecutive new patients in a similar time frame from chiropractic college clinics. PATIENTS: In the private practice setting, new patients were selected on a consecutive basis as subjects for the study. Selection was limited to low back pain patients. INTERVENTIONS: None. This was a self-report survey only. MAIN OUTCOME: There is a strong similarity of the two low back pain patient groups, with the exception of higher levels of income, work time loss, severity and functional disability reported in the private practice setting. RESULTS: Similarities between the two low back pain patient groups were found in the distribution of gender, age, job description and education. Statistical significances were not determined due to variations in data collection. CONCLUSIONS: The two patient populations are reasonably comparable in sociodemographic variables, but clinical variation does exist. These results suggest the need to consider clinical findings when extrapolating research findings in a college clinic setting to the chiropractic profession in general.

Adult↗
PubMed1992

Proposal for establishing structure and process in the development of implicit chiropractic standards of care and practice guidelines.

With the advent of health care's "era of accountability", the chiropractic profession is now faced with generating implicit standards and guidelines for care or having it done for us by outside agencies. Already we see chiropractic groups in individual states and provinces being pressured into naive efforts of guideline development. Current knowledge and experience are available through recent health care literature that clearly defines the structure and process of guideline development and offers suggestions on how to measure outcomes of those processes. In addition, the United States Congress has directed a new federal agency to oversee this activity and monitor outcomes of quality improvement programs. The time has come for the chiropractic profession to define its exact role in health care delivery and develop implicit standards of care and practice guidelines. This sentinel effort should be managed by a commissioned body of empaneled experts that generally represent the academic and clinical chiropractic profession. A protocol for selection of these panelists and the panel chairperson needs to be developed and memorialized. Appropriate methodology (with definitions) needs to be developed for the process of standards/guideline development. Adherence to the accepted structure and process of guideline development will ensure the continuity of this dynamic process in the coming generations. This proposal offers a preliminary definition of the structure and process, including a "seed" policy statement and decision flow chart, specific to guideline development. Once the structure and process of guideline development for chiropractic are defined, the profession can then present this product to federal and state agencies, private sector health care purchasers, patient advocacy groups and other stakeholders of chiropractic care.(ABSTRACT TRUNCATED AT 250 WORDS)

Chiropractic↗
PubMed1992

Functional outcomes of low back pain: comparison of four treatment groups in a randomized controlled trial.

The revised Oswestry Low Back Pain Questionnaire (ROLBPQ) and Roland-Morris Activity Scale (RMAS) were compared in a randomized controlled trial of chiropractic manipulation, stroking massage, corset and transcutaneous muscular stimulation (TMS). This trial employed specific inclusion and exclusion criteria, including nonspecific low back pain for a duration of 3 wk to 6 months and ages between 18 and 55. We had the opportunity to ask 85 patients to answer the questionnaires. Sixty-three patients, who completed the initial and final evaluations, were used for data analysis. Both ROLBPQ and RMAS showed good internal consistency with alpha coefficients ranging from .77 to .93. Both instruments showed a significant difference between the chiropractic manipulation and massage groups (p less than .05). RMAS was able to further show significant differences between the chiropractic manipulation and TMS groups, and between the corset and massage groups, but the ROLBPQ failed to do so. RMAS also showed that chiropractic manipulation had a better but nonsignificant result than corset, possibly due to insufficient sample size and/or duration of treatment. We conclude that both instruments are reliable for measuring low back pain disability, and chiropractic manipulation has a superior short-term benefit when compared to stroking massage and TMS in subacute low back pain patients. In addition, it appears that RMAS is preferable in a clinical trial situation for subacute low back pain because it is more sensitive than ROLBPQ to detect changes.

Adolescent↗