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PubMed1984

The statistical analysis of microfilarial skin snip counts: stabilization of the variance of microfilarial counts.

Microfilarial skin snip counts from savannah and rain forest areas of West Africa and from Central America were analyzed. Before parametric statistical tests, such as the comparison of means, can be properly performed, the variance must be independent of the mean. The best transformation of the skin snip counts to make the variance independent of the mean was determined. Frequency distributions of skin snip counts are shown for several different transformations. In three out of four sets of data that were examined, the best transformation was found to be the fourth root of the counts, not the logarithm of the count as has been customarily used.

Animals↗
PubMedDate not supplied

M-wave stability in H-reflex testing: analysis of three rejection criteria.

Two criteria reported in recent literature were compared with the criterion of 95% probability (using analysis of variance) for their abilities to detect significant differences in M-waves due to repositioning of the ankle joint during human soleus H-reflex testing. Data from five normal adult males were analyzed using all three rejection criteria, and results from the three analyses were compared. Variability of M-wave amplitudes within a condition was found to be quite small. Commonly used M-wave rejection criteria which do not account for within-condition variability of M-waves were shown to do a relatively poor job of detecting alterations of M-wave amplitude due to a change in ankle position.

Adult↗
PubMed1993

Histologic analysis of a screw implant retrieved from man: influence of early loading and primary stability.

This paper presents a histologic analysis of a one-piece screw implant put into immediate function and retrieved from man after 7 years of clinical function. Compact lamellar bone with many Haversian canals and osteons was found very near the metal surface, and the morphometric analysis of the perimeter of the implant showed a percentage of bone contact of 86.69% (SD = 5.43). The compact bone was particularly thickened around the top of the spires. At high-power magnification, it was possible to observe optically a small empty gap between bone and titanium, and the use of a histochemical stain (von Kossa) showed that mineralized bone was separated from the metal surface by a very thin layer of unmineralized red-stained material; this layer had the same staining features as the osteoid and the osteocyte lamina limitans.

Aged↗
PubMed1997

Analysis of longitudinal arch supports in stabilizing the arch of the foot.

Two orthotic devices commonly prescribed as arch supports were studied to evaluate their efficacy in stabilizing the foot. Fourteen cadaveric feet were mounted in a loading frame, and an axial load of 222, 445, or 667 N was applied while three-dimensional positions of the talus, calcaneus, navicular, and first metatarsal were monitored with a magnetic tracking system. Feet were tested with and without the use of two commonly prescribed arch supports. The two indices used to assess arch stabilization were arch height and joint rotation. Joint rotations consistently increased on load application. Significant differences were observed with Inserts 1 and 2 in metatarsal talar abduction, dorsiflexion and eversion, calcaneal talar eversion, and talar tibial dorsiflexion. Arch height significantly increased with both inserts. Contrary to previously published results, the arch supports that were studied provided measurable improvement in arch stability in a simulated standing at ease position.

Biomechanical Phenomena↗
PubMed1999

An opportunistic stability strategy; simulation with real data.

A multivariate modelling procedure is proposed in order to identify factors influencing stability, to estimate shelf-life, to select new batches for further stability testing and to evaluate changes in new batches. A model developed by the proposed procedure predicts the degradation rate constant as a function of storage temperature, pH, concentration and volume. The predicted rate constants were compared with prospectively measured rate constants, primarily from new batches stored under stress conditions, which emphasised batch differences earlier than storage under normal conditions. Strong deviations from expected rate constants led to extended testing of the batches concerned. The new data were used to upgrade the multivariate model. The procedure proposed led to the formulation of an opportunistic stability strategy (OSSY). Of the 15 batches of injectable solutions, nine batches are proposed tested by using OSSY. This led to an approximately 75% reduction in analytical measurements. Hold samples are recommended for storage under several stability conditions for back up analysis. In general, a multivariate stability model should be based on scientific data obtained from early studies, such as preformulation and formulation studies to provide both a qualitative and quantitative understanding of the mechanisms involved.

Contrast Media↗
PubMed2004

An early return to vigorous activity may destabilize anterior cruciate ligaments reconstructed with hamstring grafts.

OBJECTIVE: To evaluate the actual date of the return to activity and its impact on the postsurgical stability of anterior cruciate ligament reconstruction (ACLR) using hamstring grafts. DESIGN: A retrospective analysis. The time of return to activity was determined by a questionnaire at 24 to 36 months after ACLRs. SETTING: An orthopedic center. PARTICIPANTS: Fifty consecutive patients who had ACLRs using hamstring grafts 24 to 36 months earlier. INTERVENTIONS: Not applicable. Main outcome measure The time of return to activity from a questionnaire and serial KT-2000 data at 3, 6, 12, 18, and 24 months postsurgery. RESULTS: Patients were divided into 2 groups according to their KT-2000 side-to-side difference at 12, 18, and 24 months postsurgery. Group I consisted of patients whose differences were 3mm or less. Group II consisted of patients whose differences were more than 3mm. At 12 and 18 months postsurgery, significant differences were detected for the time of return to running and full-speed running. A multiple regression analysis for postsurgical stability at 24 months and the time of return to these 5 activities indicated that the time of return to full-speed running and sports activities had an effect on ACL stability. CONCLUSIONS: An early return to vigorous activities is not recommended in patients undergoing ACLRs with hamstring grafts.

Adolescent↗
PubMed1995

The role of coiled-coil alpha-helices and disulfide bonds in the assembly and stabilization of cartilage matrix protein subunits. A mutational analysis.

Cartilage matrix protein (CMP) exists as a disulfide-bonded homotrimer in the matrix of cartilage. Each monomer consists of two CMP-A domains that are separated by an epidermal growth factor-like domain. A heptad repeat-containing tail makes up the carboxyl-terminal domain of the protein. The secreted form of CMP contains 12 cysteine residues numbered C1 through C12. Two of these are in each of the CMP-A domains, six are in the epidermal growth factor-like domain, and two are in the heptad repeat-containing tail. Two major categories of mutant CMPs were generated to analyze the oligomerization process of CMP: a mini-CMP and a heptadless full-length CMP. The mini-CMP consists of the CMP-A2 domain and the heptad repeat-containing tail. In addition, a number of mutations affecting C9 through C12 were generated within the full-length, the mini-, and the heptad-less CMPs. The mutational analysis indicates that the heptad repeats are necessary for the initiation of CMP trimerization and that the two cysteines in the heptad repeat-containing tail are both necessary and sufficient to form intermolecular disulfide bonds in either full-length or mini-CMP. The two cysteines within a CMP-A domain form an intradomain disulfide bond.

Amino Acid Sequence↗
PubMed1992

Cervical stability after foraminotomy. A biomechanical in vitro analysis.

Laminectomy or facetectomy of the cervical spine, or both, may be needed for decompression of the spinal cord or of the nerve-roots. Acute stability of the cervical spine was tested after laminectomy and progressive staged foraminotomies in an in vitro model. Twelve cervical spines from human cadavera were used in the experiment. Biomechanical testing included the application of an axial load, the application of a flexion and extension moment, and the application of a torsional moment. Each specimen was tested intact, after laminectomy of the fifth cervical vertebra, and after progressive foraminotomy of the sixth cervical root. Foraminotomy was performed by resection of 25, 50, 75, and 100 per cent of the facet joint and capsule. Torsional stiffness decreased dramatically when more than 50 per cent of the facet had been resected. Statistically equivalent subsets were the intact specimen, laminectomy, 25 per cent facetectomy, and 50 per cent facetectomy in one subset, and 75 and 100 per cent facetectomy in the least-stiff subset. Flexion-moment testing showed that the posterior strain did not differ among three groups: the intact specimens, those that had been treated with laminectomy, and those that had been treated with a 25 per cent facetectomy. The 50 per cent facetectomy resulted in a 2.5 per cent increase in posterior strain, and the 75 or 100 per cent facetectomy, in a 25 per cent increase in posterior strain compared with the intact specimen. Segmental hypermobility of the cervical spine results if a foraminotomy involves resection of more than 50 per cent of the facet.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1990

Effect of excipients on the stability of levothyroxine sodium tablets.

Levothyroxine sodium tablets from two different manufacturers were analysed using the USP-NF method of analysis, a stability-indicating high pressure liquid chromatographic (HPLC) procedure. The results indicate that one particular manufacturer's 0.2-mg pink tablets contain some excipient(s) which act as a catalyst to hasten decomposition after extraction of levothyroxine for analysis. The same tablets from a different batch showed an additional long peak in the chromatogram, which indicated that the excipient(s) may have been changed. The same manufacturer has also used three different types of bottles/lids for the same product during the last year. Good manufacturing practice requires that new compatibilities/stability studies be conducted to assure the quality of the product. Ongoing stability studies are required by the Food and Drugs Administration (FDA). The use-life of 0.2-mg pink tablets of this manufacturer may be short.

17 alpha-Hydroxyprogesterone Caproate↗
PubMed1992

Effect of lumbar orthosis on intervertebral mobility. A roentgen stereophotogrammetric analysis.

To determine the stabilizing effect of external lumbar supports on the intervertebral mobility in the lower lumbar spine, seven patients with a posterolateral lumbosacral fusion without internal fixation were examined by roentgen stereophotogrammetric analysis in supine and erect positions 1 month after surgery, that is, after soft tissue healing but before fusion consolidation. Each patient was examined without lumbar support, with a molded, rigid orthosis and with a canvas corset with molded, plastic posterior support. Neither of the two types of lumbar support had any stabilizing effect on the sagittal, vertical, or transverse intervertebral translations. This study using roentgen stereophotogrammetric analysis confirms that lumbosacral orthosis has effect by restricting gross motions of the trunk rather than intervertebral mobility in the lumbar spine.

Adult↗
PubMed2026

Association of galectin-3 in systemic lupus erythematosus: A systematic review and meta-analysis.

BackgroundSystemic lupus erythematosus (SLE) is an autoimmune condition showing persistent profiling of inflammation and damage of organs and immune system. Amongst many biomarkers for such autoimmune diseases, Galectin-3 (Gal-3) a &#x3b2;-galactoside-binding lectin responsible for regulation, inflammation, and fibrosis of immune repsonses, has engrossed researchers for further investigations as a potential biomarker. However, correlation has been studied between circulating Galectin-3 levels and SLE but outcomes still remain inconsistent. Therefore, this systematic review and meta-analysis evaluated the association between circulating galectin-3 levels and SLE.Materials and MethodsPubMed, Scopus, ScienceDirect, Web of Science, and Embase databases are extensively used for literature search. The last database search was conducted on September 6, 2025. Eligible studies included case control studies reporting circulating galectin-3 levels in individuals with SLE and healthy controls. Two independent reviewers performed study selection and data extraction. Study quality was evaluated using the Newcastle-Ottawa Scale. Comprehensive Meta-Analysis software was used for statistical analysis. Pooled effect sizes were calculated as mean differences with 95% confidence intervals. Heterogeneity was assessed using the Cochrane Q test and I2 statistics, and publication bias was evaluated using Begg's funnel plot and Egger's regression analysis.ResultsSeven eligible studies were included in the meta-analysis. The pooled results showed that patients with SLE had significantly higher circulating Galectin-3 levels than healthy controls (mean difference = 8.48; 95% CI: 3.84-13.12; p < 0.0001). Substantial heterogeneity was observed across studies (Tau square: 32.57, Q = 196.03; p < 0.0001, I2 = 96.93%). Sensitivity analysis confirmed the stability of the overall findings. Begg's funnel plot and Egger's regression analysis indicated no publication bias among studies. Subgroup analysis supports the results of the overall analysis.ConclusionThis meta-analysis depicts that galectin-3 may serve as a biomarker associated with SLE pathogenesis and inflammatory activity due to significantly elevated levels of circulating galectin-3 levels in patients with systemic lupus erythematosus.

Humans↗
PubMed2003

[Kinesiologic analysis of gait and abnormal movements].

Gait disorders, postural instability and movement disorders, such as tremor, chorea or dystonia, are common complaints in day-to-day neurological practice. These conditions are quite difficult to appreciate objectively when relying on clinical observation only, yet a correct assessment of their phenomenology and an accurate measurement of their main characteristics are required to address the questions of both the underlying diagnosis and the functional impairment they may generate. By contrast, kinesiological analyses allow qualitative and quantitative studies of gait, posture and movements and may lead to specific therapeutic interventions. kinesiological analyses, which requires a high-technology laboratory conducted by a trained staff, is based on the sequential or simultaneous use of various and complementary measurement methods, whose choice is problem-oriented. Hence, the use of specific observational analysis, three-dimensional kinematic recordings, poly-electromyography and electro goniometry for the analysis of gait, the use of force plate for the analysis of postural stability and the use of electromyography and multiaxial accelerometers or gyroscopes for the analysis of movement disorders. In the present article, we review the particular features of these measurement tools and the clinical usefulness of their routine use illustrated by case reports.

Dyskinesias↗
PubMed1991

Mandibular reconstruction with a recombinant bone-inducing factor. Functional, histologic, and biomechanical evaluation.

Bone morphogenetic protein-2 (BMP-2) is a human recombinant bone-inducing factor that stimulates bone formation within 14 days. Twenty-six dogs underwent reconstruction of 3-cm full-thickness mandibular defects. After stabilizing the defects with stainless steel reconstruction plates, test implants composed of inactive dog bone matrix carrier and human recombinant BMP-2 were placed in defects of 12 animals (group 1). Control implants (carrier without BMP-2) were used in 10 animals (group 2), and no implants were placed in mandibular defects of four animals (group 3). Animals were killed at 3 and 6 months. The reconstructed segments were evaluated by roentgenography, analysis of functional stability, histology, histomorphometry, and analysis of biomechanical strength using three-point bend testing. In group 1, reconstruction plates were removed at 10 weeks because stiff, noncompressible mineralized bone formed across the defects, allowing the animals to chew a solid diet. The defects from groups 2 and 3 showed minimal, if any, bone formation and remained grossly unstable, prohibiting plate removal or advancement to a solid diet. Histomorphometric analysis at 6 months revealed that 68% of the group 1 implants were replaced by mineralized bone, whereas mineralized bone occupied less than 4% of the implants in groups 2 and 3. Biomechanical testing at 6 months revealed that the average bending strength of the reconstructed hemimandibles (expressed as a percentage of the contralateral hemimandible) was 27% for group 1 and 0% for group 2. The biomechanical strength of the defects reconstructed with BMP-2 increased significantly from 3 to 6 months and was related to degree of mineralization and thickness of bone bridging the defect.

Animals↗
PubMed2000

Two-time window and multiangle photon correlation spectroscopy size and zeta potential analysis--highly sensitive rapid assay for dispersion stability.

Polysaccharide-stabilized iron oxide particles are highly potent contrast agents in magnetic resonance imaging. After intravenous injection, the size of these small or ultrasmall particles strongly influences their distribution in the body. Knowledge about the uniformity of particle size distribution within this particle size range is not accessible by laser diffraction (lower edge of detection range), and photon correlation spectroscopy (PCS) data only yield insufficient information, the so-called polydispersity index. A combination of two-time window and multiangle analysis makes detailed characterization of particle size distribution and particle aggregation feasible, which was shown using five different iron oxide dispersions. Additional particle charge characterization yielded conclusions about the type of stabilization present in the dispersion - electrostatic or steric stabilization. Thus, this thorough particle size and charge analysis is a tool for quick detection of broad particle distributions or aggregates.

Ferric Compounds↗
PubMed2005

The stability of vocational interests from early adolescence to middle adulthood: a quantitative review of longitudinal studies.

The present meta-analysis examined the stability of vocational interests from early adolescence (age 12) to middle adulthood (age 40). Stability was represented by rank-order and profile correlations. Interest stability remained unchanged during much of adolescence and increased dramatically during the college years (age 18-21.9), where it remained for the next 2 decades. Analyses of potential moderators showed that retest time interval was negatively related to interest stability and that rank-order stability was less stable than profile stability. Although cohort standings did not moderate stability, interests of the 1940s birth cohort were less stable than those of other cohorts. Furthermore, interests reflecting hands-on physical activities and self-expressive/artistic activities were more stable than scientific, social, enterprising, and clerical interests. Vocational interests showed substantial continuity over time, as evidenced by their higher longitudinal stability when compared with rank-order stability of personality traits. The findings are discussed in the context of psychosocial development.

Adolescent↗
PubMedDate not supplied

Three-dimensional nonlinear flutter analysis of long-span suspension bridges during erection.

In this work, the aerodynamic stability of the Yichang Suspension Bridge over Yangtze River during erection was determined by three-dimensional nonlinear flutter analysis, in which the nonlinearities of structural dynamic characteristics and aeroelastic forces caused by large deformation are fully considered. An interesting result obtained was that the bridge was more stable when the stiffening girders were erected in a non-symmetrical manner as opposed to the traditional symmetrical erection schedule. It was also found that the severe decrease in the aerodynamic stability was due to the nonlinear effects. Therefore, the nonlinear factors should be considered accurately in aerodynamic stability analysis of long-span suspension bridges during erection.

Journal Article↗
PubMed2005

Stability of the Birmingham hip resurfacing arthroplasty at two years. A radiostereophotogrammetric analysis study.

The Birmingham hip resurfacing metal-on-metal arthroplasty was introduced in 1997 and has shown promising short- to mid-term results. We used radiostereophotogrammetric analysis (RSA) to study the stability of 20 resurfacing arthroplasties over a follow-up period of 24 months. Radiological examinations for RSA were performed immediately after surgery and at two, six, 12 and 24 months after operation. Precision and detection of migration thresholds (non-zero movement) were calculated. All the results corresponded well to those found in similar experimental arrangements with standard hip prostheses. Migration of the cup and vertical and mediolateral migration of the head were calculated. The values were low at two years compared with those of earlier studies of cemented femoral components in conventional total hip replacements indicating that there was no evidence of excessive early migration or loosening of the components.

Arthroplasty, Replacement↗