Biomedical subjects

C Phillips

Publications and source records attributed to C Phillips.

At least 73 records · Page 4Linked to original sources

PubMed1998

Benefit of early Class II treatment: progress report of a two-phase randomized clinical trial.

Preadolescent children with overjet greater than 7 mm were randomly assigned to observation only, headgear (combination), or functional appliance (modified bionator) and were monitored for 15 months. Of the 166 patients who completed this first phase of the trial, 147 continued to a second phase of treatment. The data from the first 107 patients to complete phase 2 are available and form the basis of this progress report. During phase 1, on average there was no change in the jaw relationship of untreated children, but 5% showed considerable improvement and 15% demonstrated worsening. Both early-treatment groups had a significant average reduction in ANB angle, more by change in maxillary dimensions in the headgear group and mandibular growth in the functional appliance group. There were wide variations in response, however, with only 75% of the treated children showing favorable skeletal response. Failure to respond favorably could not be explained by lack of cooperation alone. The preliminary results from phase 2 show that, on average, time in fixed appliances was shorter for children who underwent early treatment, but the total treatment time was considerably longer if the early phase of treatment was included. Only small differences were noted in anteroposterior jaw position between the groups at the completion of treatment, and the changes in dental occlusion, judged on the basis of Peer Assessment Rating scores, were similar between groups. Neither the severity of the initial problem nor the duration of treatment was correlated with the occlusal result. The number of patients who required extraction of permanent teeth was greater in the early functional appliance group than in the headgear or control group. The option of orthognathic surgery was presented more often in the cases of children who did not undergo early treatment, but surgery was accepted or was still being considered almost as frequently in the previous headgear group as in the controls, less often in the patients previously treated with functional appliances.

Activator Appliances↗

PubMed1998

Electroencephalographic and psychometric differences between boys with and without attention-deficit/Hyperactivity disorder (ADHD): a pilot study.

Attention-Deficit/Hyperactivity Disorder (ADHD) is reported to have an incidence of 3-5%, and is associated with a variety of interpersonal, academic, and social problem behaviors. There is controversy as to whether ADHD is a learned behavioral or brain dysfunction. Research has explored a variety of measures to assess behavioral and brain dysfunctions in this population, with no consistent and clearly diagnostic results. We investigated whether a new psychometric and a new electroencephalographic procedure would clearly differentiate ADHD. The psychometric was based on DSM-IV criteria and the EEG measure was based on the assumption that ADHD interferes with cognitive transition from one discrete task to another. Parents of four ADHD boys (ages 8-12) and four age- and interest-matched non-ADHD boys completed the ADHD Symptom Inventory, while their sons' EEG was monitored during viewing of a video and reading of a book. For the ADHD boys, this was repeated a second time, 3 months later, to assess test-retest reliability. Both the psychometric and the EEG measures clearly differentiated the two samples (p's < .01) with no overlap in scores, were reliable over 3 months (r = .87), and were significantly correlated with one another (r = .85). While a small sample size, these robust, related and reliable findings suggest that both the psychometric and the psychophysiological EEG measures deserve further replication and exploration.

Attention Deficit Disorder with Hyperactivity↗

PubMed1998

Dentofacial disharmony: psychological status of patients seeking treatment consultation.

A sample of 194 patients whose dentofacial disharmonies were severe enough to warrant an orthognathic surgical treatment option completed the SCL-90-R, a 90-item assessment tool used to measure current level of psychological distress. Two global and nine primary dimension scores of psychological distress were computed. The average interpersonal sensitivity, psychoticism, and obsessive-compulsive dimension scores were higher than the nonpsychiatric patient population norms for both males and females, but the confidence intervals for these dimensions were still in the upper end of the normal range of functioning (< 1 SD above the normative mean). No statistically significant differences by gender or age group were observed. Over 15% of the patients were clinically elevated on obsessive-compulsive behavior, interpersonal sensitivity problems, hostility, paranoid ideation, and psychoticism; and 24.7% qualified as a positive diagnosis for a psychiatric disorder. It appears that a surprisingly large number of individuals with dentofacial disharmonies who are seeking treatment consultation are experiencing a level of psychological distress that warrants intervention.

Adolescent↗

PubMed1998

Functional brain imaging of human sleep.

This paper presents an overview of the contribution of functional brain mapping to the study of human sleep. Early studies were essentially successful in describing the variations of the global level of cerebral metabolism. More recently, regional distribution of cerebral blood flow was reported. The results suggest that the permissive and executive processes of slow wave sleep and REM sleep are similar in humans and in animals. They also show cortical blood flow distributions specific to each sleep stage. The cellular mechanisms underlying the involvement of these cortical areas in sleep are not yet precisely known. They should be looked for by further investigations in animals. Future research in functional neuroimaging will attempt to explore functional and, hopefully, effective connectivity between cerebral areas involved in sleep processes. This final goal will probably require the co-registration of two or more brain imaging techniques to precisely describe the spatio-temporal course of neuronal interactions occurring during sleep.

Brain↗

PubMed1998

MEG covariance difference analysis: a method to extract target source activities by using task and control measurements.

A method is proposed for extracting target dipolesource activities from two sets of evoked magnetoencephalographic (MEG) data, one measured using task stimuli and the other using control stimuli. The difference matrix between the two covariance matrices obtained from these two measurements is calculated, and a procedure similar to the MEG-multiple signal classification (MUSIC) algorithm is applied to this difference matrix to extract the target dipole-source configuration. This configuration corresponds to the source-configuration difference between the two measurements. Computer simulation verified the validity of the proposed method. The method was applied to actual evoked-field data obtained from simulated task-and-control experiments. In these measurements, a combination of auditory and somatosensory stimuli was used as the task stimulus and the somatosensory stimulus alone was used as the control stimulus. The proposed covariance difference analysis successfully extracted the target auditory source and eliminated the disturbance from the somatosensory sources.

Algorithms↗

PubMed1998

Mite allergens: significance of enzymatic activity.

Ten years ago, the cloning and sequencing of a cDNA encoding the group I allergen of house-dust mites unequivocally determined that protein allergens may have biochemical functions in addition to their ability to bind IgE. Since this discovery, several groups have speculated that the biochemical activities of allergens, or substances associated with allergens, may be involved in their immunogenicity or allergenicity. This paper will focus on just one biochemical function, proteolytic activity, and will be illustrated by examples of our own work that we believe support the hypothesis that this category of molecules are endowed with the properties of proallergic adjuvants.

Allergens↗

PubMed1998

Environmental correlates of resident agitation in Alzheimer's disease special care units.

OBJECTIVE: To determine the point prevalence of agitated behaviors in a representative sample of Alzheimer's disease Special Care Units, and to determine the extent to which agitation is associated with aspects of the treatment environment. DESIGN: A cross-sectional study in which nonparticipant observers recorded 3723 observations of resident behaviors in 53 Alzheimer's disease Special Care Units. Observational data were gathered on the physical environment and staff treatment in these settings, and resident characteristics were extracted from a data base developed in the study states by the Health Care Financing Agency. Analyses studied the association between aspects of the staff and physical environment and resident agitation levels, controlling for resident cognitive and functional status. SETTING: Special Care Units in nursing homes in Kansas, Maine, Mississippi, and South Dakota. PARTICIPANTS: All residents and staff of the participating units. MAIN OUTCOME MEASURES: Eight specific agitated behaviors and two indexes of resident agitation were measured by direct observation by research assistants on three to four data collection walk-throughs in each of the study facilities. RESULTS: The most common agitated behaviors noted were repetitive mannerisms (4.5% of resident observations) and non-loud verbal excess (3.8%). Wandering, which frequently reflects agitation, was noted in 6.5% of resident observations. The proportion of residents exhibiting an agitated behavior varied from none in some units to 38% in one unit. Independent correlates of low unit agitation levels included favorable scores on measures of the physical environment and of staff treatment activities, low rates of physical restraint use, a high proportion of residents in bed during the day, small unit size, low levels of resident functional dependency, and fewer numbers of comorbid conditions. CONCLUSIONS: While the prevalence of agitation tends to increase as Alzheimer's disease progresses, modifiable treatment factors appear to have a strong influence on the prevalence of agitation. Both physical design and staff treatment appear to influence agitation rates, as do some measures consistent with a low stimulus approach to Alzheimer's care.

Activities of Daily Living↗

PubMed1998

Efficiency of multi-strand steel, superelastic Ni-Ti and ion-implanted Ni-Ti archwires for initial alignment.

In a clinical trial involving 155 dental arches with irregularity > 5 mm, the rate of alignment was used to compare the alignment efficiency of 16 mil superelastic Ni-Ti versus 17.5 mil triple-stranded steel archwires, and to determine whether ion implantation of the Ni-Ti wire improved its performance. Subjects were randomly assigned to archwire types; both 18 and 22 slot edgewise appliances were employed. Pre-treatment equivalence of the experimental groups was verified. Anterior irregularity was determined monthly (using Little's irregularity index) until it decreased below 2 mm, and the elastomeric ligatures were replaced at each appointment. Effective tooth movement occurred with each of the archwire types. There were no significant differences among wires, but the rate of alignment was significantly faster in the lower arch for subjects with the 22 slot appliance.

Adolescent↗

PubMed1998

A smoking cessation counsellor: should every hospital have one?

The study was performed in order to ascertain the sustained smoking cessation rate in hospital patients who received a structured programme of advice and support from a counsellor and to estimate the cost-effectiveness of such an intervention. Hospital in-patients out-patients were referred by their physician/surgeon to the smoking cessation counsellor who provided advice to reinforce that of the doctor and gave support by repeated follow-up sessions, weekly in the first month and thereafter at three, six and twelve months. Of 1,155 patients referred to the counsellor, 114 (13%) failed to keep the first appointment and 348 (30%) attended for advice on one occasion only. Among the latter, the self-reported sustained cessation rate at one year was 5%. In the 663 patients who participated in the programme the validated (expired air CO) 12-month, sustained cessation rate was 21%. Allowing 7.5% success rate among patients receiving a physician's advice only, the cost of each additional success achieved as a result of the programme is 851 Pounds and the cost per life year saved is between 340 Pounds and 426 Pounds. Assuming that after one year's abstinence relapse rates are relatively small, this represents a sound investment in the light of the cost of treating patients with smoking-related illnesses and compares favourably with other smoking cessation strategies and health care interventions.

Cost-Benefit Analysis↗

PubMed1998

Culturally sensitive validation of screening questionnaires for depression in older African-Caribbean people living in south London.

BACKGROUND: We tested the validity of two screens for depression in older African-Caribbean adults, the 15-item Geriatric Depression Scale (GDS) and a new Caribbean Culture-Specific Screen for emotional distress (CCSS). Two independent criteria were used for validity: (a) a psychiatric diagnosis derived from GMS-AGECAT, and (b) a culturally sensitive assessment of mental disorder, derived from a tool developed with local African-Caribbean religious healers. METHOD: One hundred and sixty-four consecutive African-Caribbean primary care users, aged 60 years or older, were screened with the GDS and the CCSS. Diagnostic interviews were carried out on 80% of high scorers and 20% of low scorers. RESULTS: The number of cases detected by the two separate diagnostic approaches was similar. However, the agreement between who was and who was not a case was only modest. At a cut-off of > or = 5, the GDS was an adequate case detector for psychiatric depression, and, at a cut-off of > or = 4, for 'depressed/lost spirit', as defined by culture-specific criteria. It performed as well as the new CCSS. CONCLUSIONS: At a cut-off of > or = 4 the 15-item GDS can be recommended as a case detector for significant forms of depression in older African-Caribbean people living in south London.

Aged↗

PubMed1998

Teaching the microscopic examination of urine sediment to second year medical students using the Urinalysis-Tutor computer program.

The microscopic examination of urine sediment is a common diagnostic tool taught to medical students, medical technologists, and others. The urine microscopic exam is difficult to teach because supervised instruction and textbook-based teaching suffer from numerous drawbacks. Here, we describe Urinalysis-Tutor, a computer program that uses digitized microscope images and computer-based teaching techniques to systematically teach the urine microscopic exam. In addition, we report the results of a 2-year study that evaluated the effectiveness of the program in 314 second year medical students who were required to use the program. The program contained two, 20-question exams. In the first year of the study (1996), one of the exams was chosen as the pretest and the other as the posttest; the pretest had to be completed before the students viewed the contents of the program, and the posttest was taken after finishing the tutorial. In 1997, the order of the two exams was reversed. In 1996, 159 students completed the study. The mean pretest score was 34% (SD, 14%), the mean posttest score was 71% (SD, 13%), and the improvement was significant (P <0.001, paired t-test). In 1997, 155 students participated. The mean pretest score was 41% (SD, 11%), the mean posttest score was 71% (SD, 13%), and the improvement was significant (P <0.001, paired t-test). The study shows that Urinalysis-Tutor helps medical students learn to interpret the microscopic appearance of urine sediment and that it is feasible to implement this tutorial in a medical school class.

Computer-Assisted Instruction↗

PubMed1998

Ultrastructural, cell culture and karyotype study of bone marrow in a patient with congenital dyserythropoietic anaemia (CDA)-type III presenting with recurrent still-births.

A 28 year old female patients presented with refractory anaemia since childhood and recurrent still-births at 28-30 weeks of gestation. One still-born child was hydropic at birth. Bone marrow showed characteristic morphological changes of congenital dyserythropoietic anaemia (CDA)-Type III. Electron microscopy showed disruption of the nuclear membrane, spongy appearance of nuclei, stacks of microtubules in intermediate normoblasts and myelin figures in erythroid cells. In vitro culture and karyotype data from the bone marrow of the patient is presented. Recurrent still-births in association with congenital dyserythropoietic anaemia has rarely been reported in the literature.

Adult↗

PubMed1998

Role of speech therapy and sign language prior to cochlear implantation.

The speech therapist should assess and develop the communication skills of the deaf child prior and after a cochlear implantation. The goals are first the acquisition of a useful communication system by the deaf child (for avoiding a cognitive stimulation lack) and parallely the acquisition of good oral language competencies. The different modes of communication useable in the profoundly deaf education are presented. Exclusive sign language use is not indicated in implanted children. It is well demonstrated that an exclusive oral communication is associated with an insufficient knowledge of the oral language. The total communication (combination of listening, speech reading, signing with or without finger spelling) is a defective communication mode with a bad representation of the morpho-syntactic and the phonologic aspects of the oral language. The best choice seems to be the simultaneously use of a spoken language and a manually coding of their phonological structures. The limits of this alternative are discussed.

Child↗

PubMed1997

The murine IgM secretory poly(A) site contains dual upstream and downstream elements which affect polyadenylation.

Regulation of polyadenylation efficiency at the secretory poly(A) site plays an essential role in gene expression at the immunoglobulin (IgM) locus. At this poly(A) site the consensus AAUAAA hexanucleotide sequence is embedded in an extended AU-rich region and there are two downstream GU-rich regions which are suboptimally placed. As these sequences are involved in formation of the polyadenylation pre-initiation complex, we examined their function in vivo and in vitro . We show that the upstream AU-rich region can function in the absence of the consensus hexanucleotide sequence both in vivo and in vitro and that both GU-rich regions are necessary for full polyadenylation activity in vivo and for formation of polyadenylation-specific complexes in vitro . Sequence comparisons reveal that: (i) the dual structure is distinct for the IgM secretory poly(A) site compared with other immunoglobulin isotype secretory poly(A) sites; (ii) the presence of an AU-rich region close to the consensus hexanucleotide is evolutionarily conserved for IgM secretory poly(A) sites. We propose that the dual structure of the IgM secretory poly(A) site provides a flexibility to accommodate changes in polyadenylation complex components during regulation of polyadenylation efficiency.

Alternative Splicing↗

PubMed1997

Report of the European DNA profiling group (EDNAP): an investigation of the complex STR loci D21S11 and HUMFIBRA (FGA).

This paper describes a collaborative exercise which was intended to demonstrate whether uniformity of DNA profiling results could be achieved between European laboratories using two complex short tandem repeat (STR) loci. The loci D21S11 and HUMFIBRA (FGA) were chosen because they are commonly used by different European laboratories. D21S11 has approximately 14 common alleles (f > 0.001), whereas HUMFIBRA has 19 common alleles. Laboratories were asked to test seven blood stains, one of which was a known control, and to report the results to the coordinating laboratory. The exercise demonstrated that complex STRs were amenable to standardisation.

Alleles↗

PubMed1997

Processing of vowels in supratemporal auditory cortex.

The auditory evoked neuromagnetic fields elicited by synthesized vowels of two different fundamental frequencies F0 were recorded in six subjects over the left and right temporal cortices using a 37-channel biomagnetometer. Single equivalent current dipole modeling of the fields elicited by all vowel types localized activity to a well-circumscribed area in supratemporal auditory cortex in both hemispheres. There were hemisphere asymmetries in the amplitude and latency of the M100 response. We also observed changes in M100 latency related to vowel type, but not to F0. There was no clear effect of vowel type or F0 on dipole localization for the M100, but a possible vowel type by latency interaction. These M100 data provide further evidence that vowels are processed independently of their pitch.

Adult↗

PubMed1997

Fibrinolysis, inhibitors of blood coagulation, and monocyte derived coagulant activity in acute malaria.

Different parameters of fibrinolytic systems like t-PA, PAI, D-dimer, and inhibitors of blood coagulation, i.e., protein C (PC), protein S(PS), and antithrombin III (AT-III), have been studied in cases of acute malaria due to Plasmodium falciparum and plasmodium vivax infection, and these patients were followed up. It was observed that the plasma PAI-1 was very high in cases of P. falciparum malaria infection as compared to normal controls and P. vivax infection. The changes in complicated cases of P. falciparum were remarkable as compared to uncomplicated ones. The PC, PS, and AT-III levels were also low in P. falciparum, particularly so in complicated cases, and were normal in P. vivax infection. The factor VIII R:Ag levels were invariably high in acute malaria. On follow-up of some of these cases the values came back to normal after the antiparasite treatment. The monocyte procoagulant activity was found to be significantly higher in P. falciparum infection as compared to that of P. vivax infection. All these findings therefore contribute towards the production of a hypercoagulable state in P. falciparum infection and partly explain the complications of P. falciparum infection like cerebral malaria.

Antithrombin III↗

PubMed1997

A qualitative study of breast cancer self-help groups.

This study reports on the experience of women in four community breast cancer self-help groups in Ontario, Canada. Semi-structured interviews were conducted with 24 women, asking them about benefits and limitations of their group involvement, and about their perspectives on group processes and structures. Overall, participants reported their group involvement to be extremely helpful for navigating the short and long-term impact of breast cancer. Emotional support benefits included connecting with other breast cancer survivors, feeling understood and sharing experiences, providing hope, and sharing healing laughter. Informational and practical support benefits included sharing of important information and learning how to get what you want. Even where there were concerns about limitations or tensions of group experience, these occurred against a backdrop of appreciation and commitment. From the discussion of group processes and structures, a number of issues were identified as problematic. Most notable were how to deal with deaths of group members and how to balance the group's primary purpose of providing mutual support with secondary goals of dealing with group business and engaging in meaningful advocacy.

Adaptation, Psychological↗