Transosseous suture loop technique for MPFL reconstruction

Patellar dislocation represents a rare but invalidating trauma. Indeed, 94 to 100% of patients suffer from medial patellofemoral ligament (MPFL) rupture just after the first patellar dislocation, and approximately half of these patients develop recurrent dislocations. MPFL reconstruction is a commonly performed surgery for patellofemoral instability. Anatomic reconstruction of the MPFL restores patellar stability in patients with recurrent patellar instability with neutral lower limb alignment. We describe a technique, which creates an anatomic reconstruction using trans-osseous suture loop. Conclusion: Compared to similar techniques, the described procedure has the following advantages: smaller tunnels, less donor side morbidity, reduced risk of graft failure, minimal invasiveness, more appealing cosmetic results and easily reproducible. Complications and outcomes of this technique, including the risk for patellar fracture, must be further evaluated in a larger patient cohort with longer follow-up.

Assessing reproducibility of data obtained with instruments based on continuous measurements

Data obtained with any research tool must be reproducible, a concept referred to as reliability. Three techniques are often used to evaluate reliability of tools using continuous data in aging research: intraclass correlation coefficients (ICC), Pearson correlations, and paired t tests. These are often construed as equivalent when applied to reliability. This is not correct, and may lead researchers to select instruments based on statistics that may not reflect actual reliability. The purpose of this paper is to compare the reliability estimates produced by these three techniques and determine the preferable technique. A hypothetical dataset was produced to evaluate the reliability estimates obtained with ICC, Pearson correlations, and paired t tests in three different situations. For each situation two sets of 20 observations were created to simulate an intrarater or inter-rater paradigm, based on 20 participants with two observations per participant. Situations were designed to demonstrate good agreement, systematic bias, or substantial random measurement error. In the situation demonstrating good agreement, all three techniques supported the conclusion that the data were reliable. In the situation demonstrating systematic bias, the ICC and t test suggested the data were not reliable, whereas the Pearson correlation suggested high reliability despite the systematic discrepancy. In the situation representing substantial random measurement error where low reliability was expected, the ICC and Pearson coefficient accurately illustrated this. The t test suggested the data were reliable. The ICC is the preferred technique to measure reliability. Although there are some limitations associated with the use of this technique, they can be overcome.

Burden in caregivers of cognitively impaired older adults living in the community: methodological issues and determinants

Considerable burden is reported by informal caregivers of older individuals with cognitive impairment. Significant progress in the understanding of determinants of this burden has been achieved. However, further progress could be attained if we considered important methodological issues that may have limited our understanding of caregiver burden. These issues include subgroups of care recipients and caregivers, measurement issues, research design, and statistical techniques. Fifty-three studies published between 1980 and 1997 (inclusive) that focused on caregiver burden were abstracted to determine the extent to which the methodological issues discussed above were considered. Overall, we found considerable variability among the studies surveyed. Further understanding of the caregiving process and reductions in caregiver burden will depend on the attention to methodological issues and understanding of burden across the whole caregiving career.

Development of delirium: a prospective cohort study in a community hospital

BACKGROUND

Previous research on risk of delirium in acute hospital settings identified mainly patient variables (e.g., age) that are not amenable to intervention. The purpose of this study was to develop a model for new delirium in hospitalized older patients that included process of care and social variables.

METHODS

A prospective cohort study was undertaken in a community hospital in Ontario, Canada. Research participants included 156 hospitalized patients age 65+ years and without delirium on admission who were admitted to a medical or surgical unit. The measures included daily appraisal of delirium using a standardized and validated tool, and assessment of patient, process of care, and social variables.

RESULTS

Delirium developed in 28 of the 156 patients (17.9%). Older age and cognitive impairment were significant patient variables. Significant process of care variables included a high number of medications administered during hospitalization, surgery, a high number of procedures during early hospitalization (e.g., x-rays, blood tests), and intensive care treatment.

CONCLUSIONS

Approximately one older patient in five developed delirium after admission to a medical or surgical unit. Risks not easily amenable to intervention included age, cognitive dysfunction, surgery, and intensive care requirements. Risk factors that are potentially modifiable included number of medications and number of procedures. Future research might focus on the efficacy of such intervention to reduce new-onset delirium in acute hospital settings.

Origins of accessory small ring marker chromosomes derived from chromosome 1

Three patients with accessory small ring chromosomes derived from chromosome 1 are presented together with additional clinical details and cytogenetic analyses of a previously reported patient. Cytogenetic analysis was undertaken by FISH using a reverse painting probe generated from one of the patients by microdissection of the r(1) chromosome and with a BAC923C6 which maps to 1p12. Results indicated that patients with r(1) chromosomes consisting of 1q12 heterochromatin and short arm pericentric euchromatin which extends to at least the BAC923C6 were associated with a normal or mild phenotype. Patients with abnormal phenotypes possessed two types of rings. One patient had evidence for contiguous pericentric short arm euchromatin which extended from the centromere to beyond the BAC923C6. Two patients showed molecular cytogenetic results which were compatible with non-contiguous chromosome 1 euchromatin. The diversity of origin of r(1)s will hamper attempts to define phenotype/genotype relationships.

Towards automatic cell identification in DIC microscopy

A general method is proposed for constructing templates of cells in differential interference contrast (DIC) microscopy. This takes account of the optics which generate DIC images, and is applicable to both transparent and semi-transparent cells of simple and complex shapes. Then, a template matching methodology is presented, which uses fast Fourier transforms to fit templates of a range of sizes and orientations to images. For illustration, this is used to automatically identify and measure individual Candida yeast cells in clusters.

Synthetic peptides representing discontinuous CD4 binding epitopes of HIV-1 gp120 that induce T cell apoptosis and block cell death induced by gp120

A vaccine against HIV-1 virus would block initial infection and must target conserved residues. Since initial infection depends on binding of the viral envelope protein gp120 to CD4 on the cell surface, the CD4 binding site of gp120 is a target for vaccine design. To identify the optimal biologically active site, we synthesized a series of 32-mer peptides, based on conserved residues in the C3 and C4 regions of gp120. These included three of five sequence discontinuous residues known to be involved in CD4 binding, one or two of which were substituted with alanine. We also synthesized a 44-mer peptide with an additional branch to incorporate an extra C4 region sequence including a fourth CD4 binding residue. All these peptides used an oxidized Cys-X-Cys bridge to link the discontinuous sequence elements in a manner suggested by the known conserved disulfide bridges in gp120. Polyclonal sera raised to these peptides indicate that they all contain both B and T lymphocyte epitopes. Binding of the peptides to CD4-transfected HeLa cells reveals a hierarchy dependent on the number of relevant CD4 binding residues present. Furthermore, antibody cross-linking of peptides bound to the surface of human T cells results in apoptosis that is similar to the known properties of gp120. The peptide incorporating three CD4 binding residues competitively inhibited gp 120-induced T lymphocyte apoptosis. Thus, we have synthesized novel, branched peptides incorporating conserved discontinuous sequences from two different conserved domains of HIV-1 gp120 that contain T and B lymphocyte epitopes and mimic biological functions of the native protein. These synthetic peptides are candidates for future vaccine development.

Effects of morning phototherapy on circadian markers in seasonal affective disorder

BACKGROUND

The suppression of melatonin by light at 00.30 hours has been shown to be greater in winter than in summer on patients with seasonal affective disorder (SAD) but not in matched normal controls.

METHOD

In this study 12 patients with SAD and 12 matched normal controls were exposed to morning light therapy in the winter. Melatonin profiles and sensitivity to light were measured before and after treatment.

RESULTS

The SAD but not the normal group showed a phase advance of melatonin rhythms in response to phototherapy. There was an association between phase position and phase shift in the SAD but not in the normal group.

CONCLUSIONS

There may be instability of circadian rhythms in SAD mediated by a high-amplitude phase response curve, rather than a fixed phase abnormality as had been previously suggested. This instability may be secondary to impaired serotoninergic function in the afferent pathways to the suprachiasmatic nuclei.

Effect of fluoxetine on melatonin in patients with seasonal affective disorder and matched controls

BACKGROUND

The aim was to investigate the secretion profile of melatonin and seasonal affective disorder before and after treatment with fluoxetine.

METHOD

A six-week case-controlled study with repeated overnight blood sampling was conducted. Ten patients fulfilling the criteria for major depressive disorder, seasonal type, with a 29-item Hamilton Depression Rating Scale (HDRS) score of at least 20 were compared with ten age- and sex-matched healthy controls in a clinical laboratory. The effects of fluoxetine (20 mg/day) on the HDRS and melatonin concentration were measured.

RESULTS

Fluoxetine significantly reduced melatonin levels in both groups. There was no significant difference in melatonin secretion between the groups.

CONCLUSIONS

The effect of fluoxetine differs from tricyclics and fluvoxamine, both of which increase melatonin.

Observation of pain behaviors during episodes of sickle cell disease pain

OBJECTIVE

To assess the utility of a brief behavioral observation method to quantify pain.

DESIGN

Correlational study.

PATIENTS

31 sickle cell disease (SCD) patients first seen in an outpatient clinic in painful crisis.

OUTCOME MEASURES

Observed pain behaviors, physician rating of patient pain on a 0 to 10 scale, patient rating of pain on a 0 to 10 scale, and patient pain report from the McGill Pain Questionnaire.

RESULTS

High interrater reliability for the brief behavioral observation was found, and observed pain behavior was found to correlate significantly with physician ratings of pain.

CONCLUSIONS

This study is an important first step toward developing a systematic behavior-observation methodology for the analysis of SCD pain. The current methodology was found to be reliable and easily implemented in a busy, outpatient clinic.

The Headache Self-Efficacy Scale: adaptation to recurrent headaches

This paper describes the development, construct and discriminant validity, and incremental utility of a headache self-efficacy scale. The Headache Self-Efficacy Scale is a 51 item scale designed specifically for recurrent headache sufferers. It assesses individuals' belief that they are able to do the things necessary to prevent a moderately painful headache when confronted with personally relevant headache precipitants. High self-efficacy was associated with less depression, anxiety, and physical symptoms, and less use of passive coping strategies (P < .01), even when headache frequency, intensity and chronicity were controlled statistically. Self-efficacy also explained unique variance in psychological and somatic symptoms beyond that explained by locus of control and general self-efficacy. These findings suggest that adaptation to headaches is influenced by self-efficacy beliefs, and that the assessment of self-efficacy may provide useful information in the evaluation of recurrent headache sufferers.

Community-wide outbreak of group G streptococcal pharyngitis

Although several outbreaks of group G beta-hemolytic streptococcal (GGBHS) pharyngitis have been described, doubt still remains regarding the etiologic role of GGBHS in acute pharyngitis beyond a limited number of situations. In the winter/spring of 1986/87, throat cultures were obtained from 222 consecutive children seen at a private pediatric office with acute pharyngitis and group A beta-hemolytic streptococci (GABHS) were recovered from 91 children (41%) and GGBHS from 56 children (25%). One patient had both GABHS and GGBHS isolated. This isolation rate of GGBHS was dramatically greater than in previous and subsequent years, and 67% of the GGBHS isolates occurred during an 8-week period. Results of DNA fingerprinting of the 57 isolates of GGBHS demonstrated that 43 (75%) appeared to be the same strain. The patients with GGBHS were comparable to those with GABHS with respect to clinical findings, antistreptolysin-O titer response, and clinical response to antibiotic therapy. However, patients with GGBHS were significantly older (P less than .05). This is the first well-documented, community-wide outbreak of GGBHS pharyngitis and the first respiratory outbreak of GGBHS pharyngitis in a pediatric population. GGBHS may be a more important cause of acute, treatable pharyngitis than had been previously recognized.

The headache-specific locus of control scale: adaptation to recurrent headaches

This paper describes the development, psychometric properties, and construct and incremental validity of a Headache-Specific Locus of Control Scale (HSLC). The HSLC is a 33 item scale designed specifically for recurrent headache sufferers. It assesses the individual's perceptions that headache problems and headache relief are determined primarily by: the individual's behavior (Internal factors), Health Care Professionals, or Chance factors. The psychometric properties of the HSLC were satisfactory. Among our findings were that: (1) the belief that headache problems and relief are determined by chance factors was associated with higher levels of depression, physical complaints, reliance on maladaptive pain coping strategies (p less than .001), and greater headache-related disability (p less than .01); (2) the belief that headache problems and relief are influenced primarily by the ministrations of health care professionals was associated with higher levels of medication use (p less than .01) and preference for medical treatment (p less than .001); and (3) the belief that headache problems are determined by the individual's responses and behaviors was associated with a preference for self-regulation treatment (p less than .01). These findings suggest adaptation to headache problems is influenced not only by the frequency and severity of the headache episodes, but by locus of control beliefs. The assessment of locus of control beliefs may provide useful information not typically obtained from standard medical evaluations.

Comparison of epidemic and endemic group G streptococci by restriction enzyme analysis

Restriction enzyme profiles of group G beta-hemolytic streptococci associated with a point source outbreak and an outbreak of sporadic pharyngitis in two different communities were compared. To asses the epidemiologic utility of this approach for studying group G streptococci, DNA fingerprints of strains responsible for a point source outbreak of pharyngitis associated with the consumption of contaminated food were compared with DNA fingerprints of pharyngeal isolates from children with pharyngitis seen at a pediatric practice during a 6-month period. In each epidemiologic situation, a single strain characterized by a unique restriction enzyme pattern predominated. The results are compatible with the conclusion that human infections could be limited to a few strains of group G streptococci which have the capacity to spread through a given population. The restriction enzyme profiles proved to be a highly specific and precise means of evaluating strain relatedness and of providing further understanding of the epidemiology of group G streptococcal infections.

Long-term maintenance of improvements achieved with (abortive) pharmacological and nonpharmacological treatments for migraine: preliminary findings

This report presents the first prospective comparison of the long-term maintenance of reductions in recurrent migraine headaches achieved with (abortive) pharmacological and nonpharmacological (combined relaxation training and thermal biofeedback training) treatments. Nineteen of 21 (90%) successfully treated patients (50% or greater reduction in headache activity) were contacted for follow-up evaluation 3 years later. Migraine sufferers who had been treated with ergotamine were less likely to still be relying on the treatment they had received and more likely to have additional medical treatment for their headaches and to be using prophylactic or narcotic medication than were migraine sufferers who had been treated with relaxation/biofeedback training. However, daily headache recordings revealed that patients in both treatment groups continued to show lower headache activity at 3-year follow-up than prior to treatment. Although preliminary, these findings raise the possibility that improvements achieved with nonpharmacological treatment are more likely to be maintained without additional treatment than are similar improvements achieved with abortive pharmacological treatment.

McKusick-Kaufman syndrome: report of an instructive family

We report on two sisters and their brother, all of whom are affected by McKusick-Kaufman syndrome. This sibship confirms autosomal recessive inheritance and the occurrence of the syndrome in Melanesians. It also demonstrates multisystem involvement in both sexes and illustrates difficulties in the diagnosis and management of hydrocolpos.

Altered chromatin in childhood leukaemic lymphoblasts: association with virus-like particles

An electron microscopic examination was made of masses identified as altered heterochromatin in the cytoplasm of childhood leukaemic lymphoblasts, and their relation to 'virus-like' particles (VLP). The masses were found to occur more frequently in leukaemic lymphoblasts than in normal lymphocytes, but abnormally frequent occurrence was a feature of non T rather than T or B lymphoblasts. Although these masses may be derived by phagocytosis of dead cells or cellular material, a more likely origin is by detachment of altered portions of the containing cell's own nucleus. Such in situ alterations in nuclei were seen in leukaemic lymphoblasts but not in normal lymphocytes. A close relation demonstrated between altered chromatin and VLP might suggest that VLP are a response to the presence of damaged chromatin. However, the occurrence in some VLP of solid cores and budding might make it more likely that VLP are viral, with chromatin damage as a morphologically recognizable cytopathic effect of their activity.

Lethal multiple pterygium syndrome: three consecutive cases in one family

We report on three sib fetuses with the lethal multiple pterygium syndrome (LMPS), one case occurring in a twin pregnancy. All three fetuses had a cystic hygroma and hydrops was detected by ultrasound. The classification scheme for LMPS proposed by Hall [1984] is examined. With our present state of knowledge of this syndrome, subdivision on bone-fusion types does not appear to be justified. Antenatal detection by ultrasound is possible in most pregnancies with a second affected fetus because of cystic hygroma and hydrops. In the term or near-term infant in which ultrasound has not shown cystic hygroma or hydrops, a diagnosis of Pena-Shokeir type I syndrome should be considered because pterygia are a component of that syndrome but cystic hygroma and hydrops are not.

Duplication 5q(5q22----5q33): from an intrachromosomal insertion

We report on an infant with an as yet undescribed partial duplication 5q(q22----5q33). He had a number of the already recorded manifestations of partial trisomy 5q, namely microcephaly, growth retardation, brachydactyly, long flat philtrum, thin upper lip vermilion and downturned angles of mouth and apparently low set ears. He survived only 6 months. He inherited his duplication from a maternal intrachromosomal insertion; thus he represents a pure dup(5)(q22----5q33).

Factors influencing referrals for prenatal cytogenetic diagnosis

This paper reports the results of an investigation into factors influencing the referral of women for prenatal cytogenetic diagnosis, following mid-second-trimester amniocentesis. The overall diagnostic amniocentesis rate for women over the age of 35 years was 16.8%. One hundred and forty consecutive Brisbane women referred to the 2 Queensland laboratories offering chromosome analysis of amniotic fluid cells were included in this study. 72% were referred for advanced maternal age. The socioeconomic status (SES) of the 140 women was skewed very significantly towards the professional and semiprofessional classes (Classes A and B on the Congalton Australian Four-point Scale). Twenty seven percent of all women are in SES Class D in the Brisbane population, but only 7.4% of such women (SES Class D) were within the group studied. Forty nine percent of women indicated that they themselves raised the question of prenatal diagnosis with their doctor. Diagnostic amniocentesis is not acceptable to a certain proportion of couples, but it is estimated that 60% would accept it if there were medical indications, and if it were offered. Our studies have indicated that of those women who are at increased risk of having a child with a significant chromosomal abnormality (including those over the age of 35 years) and to whom prenatal diagnosis is acceptable, 28% are actually receiving it in current practice. Those who do are a well informed, self-motivated upper and middle class group.

Effects of oligomycin and quercetin on the hydrolytic activities of the (Na+ +K+)-dependent ATPase

Quercetin inhibited a dog kidney (Na+ + K+)-ATPase preparation without affecting Km for ATP or K0.5 for cation activators, attributable to the slowly-reversible nature of its inhibition. Dimethyl sulfoxide, a selector of E2 enzyme conformations, blocked this inhibition, while the K+-phosphatase activity was at least as sensitive to quercetin as the (Na+ + K+)-ATPase activity, all consistent with quercetin favoring E1 conformations of the enzyme. Oligomycin, a rapidly-reversible inhibitor, decreased the Km for ATP and the K0.5 for cation activators, and its inhibition was also diminished by dimethyl sulfoxide. Although oligomycin did not inhibit the K+-phosphatase activity under standard assay conditions, a reaction presumably catalyzed by E2 conformations, its effects are nevertheless accommodated by a quantitative model for that reaction depicting oligomycin as favoring E1 conformations. The model also accounts quantitatively for effects of both dimethyl sulfoxide and oligomycin on Vmax, Km for substrate, and K0.5 for K+, as well as for stimulation of phosphatase activity by both these reagents at low K+ but high Na+ concentrations.

Register of chromosomal abnormalities in Queensland

The development and use of the computer-aided retrieval of karyotypes (CAROK), a register of chromosomal abnormalities in Queensland, is described. The six independent cytogenetic laboratories serving the population of 2.2 million contribute data to the register which provides total population information on the occurrence of chromosomal abnormalities, without selection. CAROK policy on confidentiality, security, access, and safety of data is described in detail. A cytogenetic register such as this ensures a reliable permanent file of results, facilitates research, and provides a data base which will enable questions of clustering or secular trends to be answered efficiently. The register is complete for the years 1976-1981, and contains information on 880 consecutive abnormal cases; in this sense, the data constitute an unselected six-year series of diagnosed chromosomal abnormalities in Queensland. These figures show an average incidence figure (over a six-year period) for newly diagnosed cases of chromosomal abnormality of 6.61/100 000 general population per year.

The dup(3)(p25 leads to pter) syndrome: a case with holoprosencephaly

We report a patient with dup(3p) syndrome with holoprosencephaly. This infant is compared with 17 others reported previously with banding studies. In 72% of cases the duplication derived from a mother with a balanced translocation; 78% of affected individuals are males. The most common anomalies are characteristic facial changes, congenital heart defects, and hypoplasia of male genitalia. Holoprosencephaly has not been reported before in the dup(3p) syndrome.

The ring chromosome 13 syndrome

A study of the ring chromosome 13 syndrome is presented with detailed clinical and cytogenetic features of three new unrelated cases. The clinical limits of this syndrome can now be defined. An analysis of these cases together with those in the literature indicates that the syndrome forms a continuous spectrum, and no further taxonomic subdivision is possible at this stage of knowledge. The chromosome breakpoints in the first two cases are 13p11 and 13q32 and in the third case 13p11 and 13q33 or 13q34. All described cases of the ring 13 syndrome have breakpoints within the region bounded by bands 13q21 to 13q34. All rings are negative for silver banding. Peripheral blood cultures showed an average of 88% of metaphases to be 46,XX,r(13), with the remaining 12% manifesting either random loss or ring duplication. The rings vary in size and show a variable number of centromeres. An estimate of the birth incidence of this condition in the Anglo-Saxon population is 1 in 58,000. Parents of affected children are clinically and cytogenetically normal, the rings in affected offspring being meiotic in origin.

A ? developmental characteristic of the ultrastructure of childhood leukaemic lymphoblasts

Areas of chromatin demarcated from the rest of the nucleus ("separations") were found frequently in acute lymphoblastic leukaemias of childhood, in some patients in apparently all leukaemic cells, but rarely in non-lymphocytic leukaemias. In normal lymphocytes, separations were most common in fetal thymus, and less frequent in fetal lymph node and bone marrow, and child thymus, lymph node and marrow. Separations may be a developmental marker, and fetal lymphoid tissues, especially thymus, may have significance in the origin of lymphoblastic leukaemias of childhood. Nuclear loops enclosing cytoplasmic material were associated with, and may have similar significance to, separations.