GORE-TEX SCLERAL-SUTURED ENVISTA INTRAOCULAR LENS DISLOCATION: THREE CASES AND AN ASSESSMENT OF EYELET TENSILE STRENGTH, FRACTURE CHARACTERISTICS, AND RISK FACTORS.

PURPOSE: Three cases of dislocation of a Gore-Tex scleral-sutured EnVista intraocular lens are reported. The tensile strength of the lens eyelets under two suturing methods is assessed. Pursuant surgical considerations are discussed. METHODS: A chart review was performed to identify cases of scleral-sutured EnVista lens dislocations. In addition, six EnVista lenses were suspended in a balanced salt solution tank, tied either with suture over haptic or simple pass technique. Eyelet tensile strength was calculated by gradual addition of weights. Eyelet fracture position and width were measured. The tensile strength of one additional EnVista lens was assessed in open air. PATIENTS: In a retrospective, consecutive case series, three dislocated lenses were identified out of 17 surgeries from one institution. Two dislocations occurred postoperatively, and one occurred intraoperatively. RESULTS: The EnVista eyelet demonstrated greater tensile strength tied with the simple pass method (0.27 ± 0.017 N, n = 3) than with the suture over haptic method (0.15 ± 0.016 N, n = 3; P = 0.0015). Eyelet fracture location corresponded to tensile strength. The lens in air withstood greater tensile stress. CONCLUSION: Stress is placed on different regions of the eyelet with each suturing method. Simple pass may withstand greater tension and decrease risk for lens fracture, but the operating surgeon must consider multiple factors when forming an operative plan.

Implementation of basic quality control tests for malaria medicines in Amazon Basin countries: results for the 2005-2010 period.

BACKGROUND: Ensuring the quality of malaria medicines is crucial in working toward malaria control and eventual elimination. Unlike other validated tests that can assess all critical quality attributes, which is the standard for determining the quality of medicines, basic tests are significantly less expensive, faster, and require less skilled labour; yet, these tests provide reproducible data and information on several critical quality attributes, such as identity, purity, content, and disintegration. Visual and physical inspection also provides valuable information about the manufacturing and the labelling of medicines, and in many cases this inspection is sufficient to detect counterfeit medicines. The Promoting the Quality of Medicines (PQM) programme has provided technical assistance to Amazon Malaria Initiative (AMI) countries to implement the use of basic tests as a key screening mechanism to assess the quality of malaria medicines available to patients in decentralized regions. METHODS: Trained personnel from the National Malaria Control Programmes (NMCPs), often in collaboration with country's Official Medicine Control Laboratory (OMCL), developed country- specific protocols that encompassed sampling methods, sample analysis, and data reporting. Sampling sites were selected based on malaria burden, accessibility, and geographical location. Convenience sampling was performed and countries were recommended to store the sampled medicines under conditions that did not compromise their quality. Basic analytical tests, such as disintegration and thin layer chromatography (TLC), were performed utilizing a portable mini-laboratory. RESULTS: Results were originally presented at regional meetings in a non-standardized format that lacked relevant medicines information. However, since 2008 information has been submitted utilizing a template specifically developed by PQM for that purpose. From 2005 to 2010, the quality of 1,663 malaria medicines from seven AMI countries was evaluated, mostly collected from the public sector, 1,445/1,663 (86.9%). Results indicate that 193/1,663 (11.6%) were found not to meet quality specifications. Most failures were reported during visual and physical inspection, 142/1663 (8.5%), and most of these were due to expired medicines, 118/142 (83.1%). Samples failing TLC accounted for 27/1,663 (1.6%) and those failing disintegration accounted for 24/1,663 (1.4%). Medicines quality failures decreased significantly during the last two years. CONCLUSIONS: Basic tests revealed that the quality of medicines in the public sector improved over the years, since the implementation of this type of quality monitoring programme in 2005. However, the lack of consistent confirmatory tests in the quality control (QC) laboratory, utilizing methods that can also evaluate additional quality attributes, could still mask quality issues. In the future, AMI countries should improve coordination with their health authorities and their QC lab consistently, to provide a more complete picture of malaria medicines quality and support the implementation of corrective actions. Facilities in the private and informal sectors also should be included when these sectors constitute an important source of medicines used by malaria patients.

Development and validation of 14 human serum protein assays on the Roche cobas® c 501.

Many laboratories rely on dedicated nephelometers and turbidimeters for the measurement of serum proteins. There are, however, a number of chemistry analyzers that offer open channel configurations for end-user applications. We developed and validated 14 human serum protein assays (α(1)-antitrypsin, α(2)-macroglobulin, albumin, apolipoproteins AI and B, complement components 3 and 4, haptoglobin, immunoglobulins A, G, and M, orosomucoid, transferrin, and transthyretin) on the Roche cobas(®) c 501. We obtained excellent precision at low, normal, and high physiologic concentrations of each protein (within-run imprecision CVs ≤2.5%, total imprecision CVs ≤3.6%). Linearity for each method was within 5% of the expected value throughout the calibration range, and method comparison studies to commercial assays from Roche or Siemens were in good agreement (r>0.975). We observed no significant interference from bilirubin (up to 414 mg/l), hemoglobin (up to 8.9 g/l), triglyceride (up to 28 g/l), or rheumatoid factor (up to 3,930 IU/ml). Calibration was stable for at least 14 days. The instrument's small reaction cell allowed us to conserve nearly 60% of our specimen and reagent volume compared with our previous system. These newly developed assays provide precise and accurate results with high throughput, but without the associated cost of a dedicated instrument.

Maternal obesity and markers of inflammation in pregnancy.

OBJECTIVES: To evaluate whether obesity is associated with changes in pro-inflammatory and immunomodulatory cytokines in pregnancy. METHODS: We performed a cross-sectional study using maternal serum from the early second trimester to examine biomarkers associated with inflammation in relation to maternal body mass index (n=80 total). RESULTS: Leptin and high sensitivity C-reactive protein were significantly different between groups and increased with increasing body mass index. MCP-1 was significantly increased in the morbidly obese mothers. Interleukin-2 exhibited a U-shaped relationship with body mass index; transforming growth factor-beta1 demonstrated a nonsignificant negative trend with body mass index; and the levels of hepatocyte growth factor and tumor necrosis factor-alpha did not differ appreciably between groups. CONCLUSIONS: Maternal obesity in pregnancy is associated with changes in cytokines, protein hormones and acute phase proteins in the second trimester, with an increase in MCP-1 in the morbid obesity category, and an increase in Leptin and hsCRP with increasing BMI category.

Evaluation of the recombinant VlsE-based liaison chemiluminescence immunoassay for detection of Borrelia burgdorferi and diagnosis of Lyme disease.

Recent efforts to improve the serologic diagnosis of Lyme disease have included the use of a synthetic peptide (C6) that reproduces the sequence of invariable region 6 of VlsE, the variable surface antigen of Borrelia burgdorferi. In the present study, the diagnostic performance of DiaSorin's recombinant VlsE-based chemiluminescence immunoassay in 1,947 human serum samples was evaluated. Sensitivity was determined using two serum panels from the CDC. For panel I, we observed sensitivities of 68.4% and 75.6% for subjects with early, localized (n=19) or disseminated (n=41) disease, respectively. For panel II, we observed sensitivities of 61.5% and 100% for subjects with early (n=26) or late-stage (n=11) disease, respectively. We observed a specificity of 99.5% for healthy donors (n=600) living either in regions of the United States where the disease is endemic or in regions where it is not endemic. Overall, specificity among 207 potentially cross-reactive sera from subjects who had other spirochetal infections, nonspirochetal infections including bacterial and viral infections, or autoimmune or neurologic disease; who were positive for rheumatoid factor or anti-mouse antibodies; or who had been previously vaccinated for Lyme disease was 93.7%. In a direct comparison of 1,038 prospectively collected samples for Lyme disease testing we observed a relative sensitivity of 70%, a relative specificity of 99.1%, and an overall agreement of 97.1% between the DiaSorin recombinant VlsE chemiluminescence immunoassay and the Immunetics peptide-based C6 enzyme-linked immunosorbent assay.

Serologic associations of anti-cytoplasmic antibodies identified during anti-nuclear antibody testing.

BACKGROUND: There are currently no guidelines concerning additional laboratory testing for specific autoantibodies among anti-nuclear antibody-negative sera with an anti-cytoplasmic staining pattern identified by indirect immunofluorescence assay. Moreover, few data are available that address this laboratory situation. METHODS: We performed specific autoantibody assays in 200 sera with an anti-nuclear antibody titer < or =1:32 and a cytoplasmic titer (undefined staining pattern) of > or =1:64, identified sequentially in the course of routine anti-nuclear antibody testing. RESULTS: A total of 85 sera (42.5%) were positive in one (n=57) or more (n=28) of the specific autoantibody tests performed. Autoantibodies identified were antimitochondrial (15%), antimicrosomal (13%), anti-neutrophil cytoplasmic (10%), anti-smooth muscle (6%), anti-parietal cell (4%), and extractable nuclear antigen (8.5%, including histones, SSA, SSB, Sm, Jo-1 or Scl-70). A positive result in one or more of these assays was more frequent at anti-cytoplasmic titers > or =1:1024 (77.8%) than at titers of 1:64-1:128 (7%) (chi2=25.3, p<0.001). CONCLUSIONS: The present data demonstrate that undefined anti-cytoplasmic staining in anti-nuclear antibody-negative sera is associated with, although not necessarily caused by, a high frequency and wide range of specific autoantibodies. Further work is needed before specific recommendations can be made concerning follow-up in subjects with this laboratory finding.

Commutability of the CRM 470 C-reactive protein value in the Dade Behring N High Sensitivity CRP assay.

Certified Reference Material 470 (CRM 470) demonstrates commutability with both the manufacturer's calibrator and with dilutions of serum pools in the Dade Behring N High Sensitivity assay for C-reactive protein (CRP). Both regression and back calibration show similar nonlinearity for all materials, largely due to the method of calibration curve fitting used in this assay. Significant differences in values among the currently available commercial assays can be largely overcome by using appropriate calibration curve fitting and the recommended value transfer protocol, which includes a minimum of two assay runs on each of at least 3 separate days, with weight correction of all reconstitutions and dilutions. An initial weight-corrected dilution should be made each day because of the relatively high level of CRP in CRM 470. In our opinion, the degree of nonlinearity, imprecision, and differences in values in currently available assays renders the use of fixed clinical decision cut-points questionable for high-sensitivity CRP. An alternative approach is suggested.

Development of immunoturbidimetric assays for fourteen human serum proteins on the Hitachi 912.

Many laboratories rely on dedicated nephelometers or turbidimeters and commercial reagent kits for the evaluation of serum proteins. However, with growing emphasis on cost containment, laboratories are forced to seek additional operational efficiencies by capitalizing on the use of existing analyzers whenever possible. In the present paper we describe the development of immunoturbidimetric assays for routine analysis of 14 human serum proteins (alpha1-antitrypsin, alpha2-macroglobulin, albumin, apolipoproteins Al and B, complement components 3 and 4, haptoglobin, immunoglobulins A, G, and M, orosomucoid, prealbumin, and transferrin) on the Hitachi 912, a general chemistry analyzer. With this system, we obtained excellent precision at levels corresponding to low, normal, and high physiologic concentrations of each protein (within-run imprecision CVs < or = 3.4%, total imprecision CVs < or = 4.1%). Linearity for each method was within 5% of the expected value throughout the calibration range, and method comparisons with either the Roche turbidimetric or Dade Behring nephelometric assays were in good agreement (r >0.97). We observed no significant interference from bilirubin (up to 718 micromol/l), hemoglobin (up to 8 g/l), triglyceride (up to 14.7 mmol/l) or rheumatoid factor (up to 4,140 IU/ml). Calibration for the 14 protein assays was stable for at least 7 days and onboard refrigerated reagents were stable for at least 3 months. The instrument's automated sample re-run feature minimized sample handling and helped to conserve specimens. In conclusion, the newly developed assays on the Hitachi 912 offer high throughput (>250 tests per hour) without the associated cost of a dedicated instrument for protein assays.