Persistent Anti-Borrelia IgM Antibodies without Lyme Borreliosis in the Clinical and Immunological Context.

The aim of the study was to investigate the etiology of persistent IgM antibodies against Borrelia burgdorferi sensu lato (sl) and to analyze their association with nonspecific symptoms. The study group comprised individuals with persistent IgM antibodies in the absence of IgG. The relation between ELISA values and time elapsed since past erythema migrans (EM) was analyzed. Previous antibiotic treatments were assessed. The association between persistent IgM and nonspecific symptoms was evaluated statistically. Specificity of IgM antibodies for outer surface protein C (OspC) of B. burgdorferi sl was examined by immunoblotting. Further, we investigated the cross-reactivity with Borrelia-unrelated proteins. Fifty-nine patients (46 women; 78%) were included in the study group. The mean IgM-ELISA values did not change significantly during follow-up (median 6.2 months). The mean ELISA value in the study group was dependent on time elapsed since past EM. Nonspecific symptoms improved significantly more often in patients with lower IgM ELISA results. Persistent IgM antibodies were specific for the C-terminal PKKP motif of OspC. Cross-reacting C-terminal PKKP antigens from both human and prokaryotic origins were identified. We demonstrate that the C-terminal PKKP motif plays a main role for the reactivity of persistent Borrelia IgM toward OspC. However, cross-reactivity to other eukaryotic and/or prokaryotic antigens may hamper the specificity of OspC in the serological diagnosis of Lyme borreliosis. Lack of improvement of nonspecific symptoms was associated with higher IgM ELISA values. IMPORTANCE The reactivity of human IgM with the outer surface protein C (OspC) of Borrelia burgdorferi sensu lato is frequently used to detect Borrelia specific IgM in commercial immunoassays, and such antibodies usually occur in the early phase of the infection. We identified a group of individuals with persistent Borrelia IgM without symptoms of Lyme borreliosis. We used their sera to demonstrate that the C-terminal epitope of OspC binds the IgM. Strikingly, we found that the same epitope occurs also in certain proteins of human and environmental origin; the latter include other bacteria and food plants. Our experimental data show that these Borrelia-unrelated proteins cross-react with the OpsC-specific IgM. This knowledge is important for the development of serologic assays for Lyme borreliosis and provides a cross-reactive explanation for the persistence of Borrelia-IgM.

Neuroretinal atrophy following resolution of macular oedema in retinal vein occlusion.

BACKGROUND/AIMS: To characterise neuroretinal atrophy in retinal vein occlusion (RVO). METHODS: We included patients with central/branch RVO (CRVO=196, BRVO=107) who received ranibizumab according to a standardised protocol for 6 months. Retinal atrophy was defined as the presence of an area of retinal thickness (RT) <260 µm outside the foveal centre. Moreover, the thickness of three distinct retinal layer compartments was computed as follows: (1) retinal nerve fibre layer to ganglion cell layer, (2) inner plexiform layer (IPL) to outer nuclear layer (ONL) and (3) inner segment/outer segment junction to retinal pigment epithelium. To characterise atrophy further, we assessed perfusion status on fluorescein angiography and best-corrected visual acuity (BCVA), and compared these between eyes with/without atrophy. RESULTS: 23 patients with CRVO and 11 patients with BRVO demonstrated retinal atrophy, presenting as sharply demarcated retinal thinning confined to a macular quadrant. The mean RT in the atrophic quadrant at month 6 was 249±26 µm (CRVO) and 244±29 µm (BRVO). Individual layer analysis revealed pronounced thinning in the IPL to ONL compartment. Change in BCVA at 6 months was similar between the groups (BRVO, +15 vs +18 letters; CRVO, +14 vs +18 letters). CONCLUSIONS: In this exploratory analysis, we describe the characteristics of neuroretinal atrophy in RVO eyes with resolved macular oedema after ranibizumab therapy. Our analysis shows significant, predominantly retinal thinning in the IPL to ONL compartment in focal macular areas in 11% of patients with RVO. Eyes with retinal atrophy did not show poorer BCVA outcomes.

Impact of infrared radiation on UVB-induced skin tumourigenesis in wild type C57BL/6 mice.

Although infrared radiation (IR) represents more than 50% of the solar radiation reaching the Earth's surface, this waveband has been hardly investigated in terms of tumourigenesis. The objective of the present study was to investigate the influence of IR on ultraviolet B (UVB)-induced carcinogenesis in male and female wild type mice. For this purpose, male and female C57BL/6N mice were subjected to a long-term irradiation protocol. Mice were irradiated once neonatally and from the age of eight weeks for 36 weeks with a cumulative dose of 576 kJ m-2 UVB and/or 78 895 kJ m-2 IR. In order to resemble natural sun irradiation, exposure to physiological doses of UVB and IR was performed simultaneously. Mice were screened for arising lesions twice a week. Lesions were excised and histologically diagnosed. Kaplan-Meier analyses were carried out and lesion counts and cumulated hazard rates for the development of lesions in the UVB and IR + UVB-exposed groups in male and female mice were compared. We found that IR-exposure did not change the number of epithelial malignant tumours in UVB-exposed wild type mice. In combination with IR there was a tendency of more tumours with increased malignancy: 23 vs. seven spindle cell shaped sarcomas and seven vs. two MelanA+/S100+ tumours in groups of 35 C57BL/6 mice. IR did not influence UVB-induced carcinogenesis differently in male and female mice. However, comparing UVB and sham irradiated animals irrespective of IR exposure, UVB-induced non-epithelial tumours arose significantly earlier in male mice than in female mice.

Automated tube voltage selection in pediatric non-contrast chest CT.

BACKGROUND: Modern CT scanners provide automatic dose adjustment systems, which are promising options for reducing radiation dose in pediatric CT scans. Their impact on patient dose, however, has not been investigated sufficiently thus far. OBJECTIVE: To evaluate automated tube voltage selection (ATVS) in combination with automated tube current modulation (ATCM) in non-contrast pediatric chest CT, with regard to the diagnostic image quality. MATERIALS AND METHODS: There were 160 non-contrast pediatric chest CT scans (8.7±5.4 years) analyzed retrospectively without and with ATVS. Correlations of volume CT Dose Index (CTDIvol) and effective diameter, with and without ATVS, were compared using Fisher's z-transformation. Image quality was assessed by mean signal-difference-to-noise ratios (SDNR) in the aorta and in the left main bronchus using the independent samples t-test. Two pediatric radiologists and a general radiologist rated overall subjective Image quality. Readers' agreement was assessed using weighted kappa coefficients. A p value <0.05 was considered significant. RESULTS: CTDIvol correlation with the effective diameter was r = 0.62 without and r = 0.80 with ATVS (CI: -0.04 to -0.60; p = 0.025). Mean SDNR was 10.88 without and 10.03 with ATVS (p = 0.0089). Readers' agreement improved with ATVS (weighted kappa between pediatric radiologists from 0.1 (0.03-0.16) to 0.27 (0.09-0.45) with ATVS; between general and each pediatric radiologist from 0.1 (0.06-0.14) to 0.12 (0.05-0.20), and from 0.22 (0.11-0.34) to 0.36 (0.24-0.49)). CONCLUSION: ATVS, combined with ATCM, results in a radiation dose reduction for pediatric non-contrast chest CT without a loss of diagnostic image quality and prevents errors in manual tube voltage setting, and thus protecting larger children against an unnecessarily high radiation exposure.

Concordance of three alternative gestational age assessments for pregnant women from four African countries: A secondary analysis of the MIPPAD trial.

BACKGROUND: At times, ultrasound is not readily available in low resource countries in Africa for accurate determination of gestational age, so using alternative methods is pivotal during pregnancy. These assessments are used to aid the risk analysis for an infant and management strategies for premature delivery, if necessary. Currently, date of last menstrual period, fundal height measurements, and the New Ballard Score are commonly used in resource-limited settings. However, concordance of these measures is unknown for sub-Saharan Africa. We obtained data from an open-label randomized controlled trial, to assess the concordance of these alternative assessment methods. The purpose of our study was to determine the agreement between these alternative methods when used in sub-Saharan African populations. METHODS: A total of 4,390 pregnant women from Benin, Gabon, Mozambique and Tanzania were included in our analysis. The assessment methods compared were: 1) reported last menstrual period, 2) symphysis-fundal height measurement, and 3) the New Ballard Score. The Bland-Altman method and intraclass correlation coefficient (ICC) were used to test the degree of agreement. Survival range gestational age, used as an inclusion criterion for further analysis, was from 22 to 44 weeks. FINDINGS: Plots showed a lack of agreement between methods and the 95% limits of agreement too wide to be clinically useful. ICC = 0.25 indicated poor agreement. A post-hoc analysis, restricted from 32 to 42 weeks, was done to check for better agreement in this near-term population. The plots and ICC = 0.16 still confirmed poor agreement. CONCLUSION: The alternative assessments do not result in comparable outcomes and discrepancies are far beyond the clinically acceptable range. Last menstrual period should not be used as the only estimator of gestational age. In the absence of reliable early ultrasound, symphysis-fundal height measurements may be most useful during pregnancy for fetal risk assessment and the New Ballard Score after delivery as a confirmation of these estimations and for further neonatal management. However, promotion of portable ultrasound devices is required for accurate assessment of gestational age in sub-Sahara Africa.

Efficacy of different revision procedures for infected megaprostheses in musculoskeletal tumour surgery of the lower limb.

PURPOSE: The incidence of recurrent infections in patients following one or two stage revision for infected megaprostheses after resection of bone tumours was investigated. The difference between retaining at least one well fixed stem and a complete removal of the megaprosthesis during a two stage revision was also analysed. METHODS: 627 patients who experienced a replacement of a musculoskeletal tumour by megaprostheses were recorded. An infection occurred in 83 of 621 patients available for follow-up. 61 patients underwent one stage revision, and 16 patients two stage revision for the first revision surgery. In the entire study period, two stage revision was performed 32 times (first, second, and third revision). RESULTS: The cumulative incidence analysis showed a reinfection probability after one stage revision of 18% at one year, 30% at two years, 39% at five years, 46% at ten years, and 56% at 15 years. After two stage revision, a reinfection probability of 28% at two years, and 48% at five years was calculated. Cumulative incidence curves did not differ significantly (Gray's test; p = 0.51) between one and two stage revision (with and without complete removal of the stems). In two stage revision (n = 32), a statistically significant difference in infection rates between patients treated with complete removal of the megaprosthesis (n = 18) including anchorage stems and patients with at least one retained stem (n = 14) was shown (Fisher's exact test, p = 0.029). CONCLUSION: Two stage revisions with complete removal of the megaprosthesis showed the best results among limb salvage procedures for the treatment of infected megaprosthesis.

Hand MRI and the Greulich-Pyle atlas in skeletal age estimation in adolescents.

OBJECTIVE: To evaluate the feasibility of hand MRI in age assessment in adolescents using the Greulich-Pyle (GP) atlas criteria. MATERIALS AND METHODS: Two radiologists, who were blinded to the study subjects' chronologic ages, semi-objectively evaluated 1.5-T MRIs of the left hands of ten patients (13.5 ± 2.6 years) who had left-hand radiographs and 50 healthy volunteers (15 ± 2 years). RESULTS: A coronal T1-weighted, volumetric, interpolated, breath-hold examination with water excitation (T1 VIBE-3D-WE) achieved the best image quality. The correlation between estimated patients' ages on radiographs and MRI was high. The average estimated age difference between the MRIs and radiographs was -0.05 years for reader 1 and -0.175 years for reader 2. The interclass coefficients (ICCs) showed high interobserver agreement (radiographs: ICC = 0.95, MRI: ICC = 0.97). The ICC, calculated separately for the male and female volunteers' estimated ages by MRI, also showed a high agreement between the two readers (male: ICC = 0.97, female: ICC = 0.95). Reader 1 estimated 94% of volunteers within 2 standard deviations (SD) and 62% within 1 SD. The results for reader 2 were 92% and 54%, respectively. Thirty-nine percent of girls and 27% of boys were estimated to be older using 1 SD. CONCLUSION: MRI of the left hand is a feasible alternative to hand radiographs for skeletal age estimation in adolescents using the GP criteria with 2 SD. Using 1 SD, the age of healthy volunteers tended to be estimated as higher than the chronologic age. Future studies should evaluate the results in a larger number of participants.

Estradiol impairs the antiproliferative and proapoptotic effect of Zoledronic acid in hormone sensitive breast cancer cells in vitro.

BACKGROUND: Zoledronic acid (ZA) has antiresorptive effects and protects from bone metastasis in women with early breast cancer. In addition, in postmenopausal women with endocrine responsive breast cancer ZA prolongs DFS. The exact mechanism is still unclear. We have therefore investigated the effect of increasing concentrations of ZA in breast cancer cell lines in the absence or presence of estradiol to mimic the hormonal environment in vitro. MATERIALS AND METHODS: Using assays for cell proliferation (EZ4U, BrdU) and cell death (Annexin/PI), we have analyzed the dose-dependent antiproliferative and pro-apoptotic effects of ZA in two hormone sensitive cell lines (MCF-7 and T47D) and a hormone insensitive, triple negative cell line (MDA-MB-231) in the presence of 0, 1 and 10 nM estradiol. RESULTS: In the absence of estradiol, ZA exerts dose-dependent antiproliferative and pro-apoptotic antitumor effects in both, hormone sensitive (MCF-7, T47D) and -insensitive (MDA-MB-231) breast cancer cell lines (p<0.0001). In the presence of estradiol, the antitumoral effect of ZA was significantly decreased only in the hormone sensitive MCF-7 and T47D cell lines (p = 0.0008 and p = 0.0008, respectively). CONCLUSION: We have demonstrated that estradiol impairs the antiproliferative and proapoptotic effect of ZA in hormone sensitive, but not in hormone insensitive breast cancer cell lines. Our findings provide a possible explanation for the differential effect of ZA on DFS in pre- and postmenopausal patients with hormone sensitive early breast cancer, which has been demonstrated clinically. We further hypothesize that endocrine insensitive tumors such as triple negative breast cancer (TNBC) should benefit from ZA irrespective of their menopausal status.

The Distribution of Leakage on Fluorescein Angiography in Diabetic Macular Edema: A New Approach to Its Etiology.

Purpose: To determine the distribution of leakage on fluorescein angiography (FA) and explore the clinically protective role of astrocytes against damage to the inner blood retinal barrier (iBRB) in diabetic macular edema (DME). Methods: A consecutive case series of 87 eyes of 87 patients with DME was included. We measured the leakage area in each field of the Early Treatment Diabetic Retinopathy Study (ETDRS) grid on late-phase FA images. The normative thickness of the nerve fiber layer (NFL), in which the astrocytes are confined, was derived from a previous work using spectral-domain optical coherence tomography. We explored the difference in leakage areas in every two fields. Moreover, we investigated the correlation between the mean of the leakage area and the mean of thickness of the NFL in each ETDRS field. Results: The leakage areas in the nasal, inferior, superior, and temporal fields were 2.34 mm2, 2.84 mm2, 3.03 mm2, and 3.96 mm2. The difference in leakage area between each two fields was significant in all cases (P < 0.05) except between the inferior and superior fields (P = 0.65). The temporal field was the only field that showed leakage in all 87 cases. The correlation between the leakage area and the thickness of the NFL in the ETDRS fields was negative and highly significant: r = -0.96 (95% confidence interval -0.99 to -0.02). Conclusion: The distribution of leakage correlates inversely and statistically significantly with the thickness of the NFL, suggesting astrocytes in the NFL play a pivotal role in preventing damage to the iBRB and subsequent evolution of microaneurysms in DME. Moreover, fluid extravasation due to damage to the iBRB is expressed earlier in the temporal than in the other three fields.

Microvascular function in women with former gestational diabetes: A cohort study.

OBJECTIVE: In the long term, diabetes mellitus is potentially associated with the occurrence of microvascular damage. This study sought to assess whether a history of prior gestational diabetes mellitus is associated with long-term effects on the women's microcirculation. METHODS: Within the scope of a long-term follow-up of the 'Viennese Post-Gestational Diabetes Project', women with prior gestational diabetes mellitus as well as women with previous pregnancy but with no history of gestational diabetes mellitus (controls) were enrolled in this cross-sectional study. Microvascular function was assessed by post-occlusive reactive hyperaemia using laser Doppler fluxmetry. Baseline perfusion, biological zero, peak perfusion, time to peak and recovery time were recorded and compared between both groups. RESULTS: Microvascular function was assessed in 55 women with prior gestational diabetes mellitus (46.1 ± 4.6 years) and 32 women with previous pregnancy but without prior gestational diabetes mellitus (42.9 ± 5.3 years). The mean period of time between delivery and the assessment of microvascular function was 16.2 ± 5.2 years in women with prior gestational diabetes mellitus group and 14.2 ± 4.8 years in controls. Regarding microvascular function, baseline perfusion, biological zero, peak perfusion, time to peak and recovery time did not differ between women with prior gestational diabetes mellitus and controls (all p > 0.05). CONCLUSION: In the long term, microvascular function appears not to be impaired in women with prior gestational diabetes mellitus.

Supraclavicular Approach to the Subclavian Vein as an Alternative Venous Access Site for ECMO Cannulae? A Retrospective Comparison.

Venous reperfusion and double-lumen cannulae for extracorporeal membrane oxygenation (ECMO) are usually inserted via the right internal jugular vein. The supraclavicular approach to the right or left subclavian vein could serve as a possible alternative. The aim of this analysis was to compare feasibility, complications, and performance of supraclavicular and jugular cannulation. We retrospectively analyzed charts and registry data of patients undergoing venovenous ECMO. Twenty-four patients underwent jugular cannulation, and 11 patients underwent supraclavicular cannulation. Ten patients underwent femoro-jugular, and five patients underwent femoro-supraclavicular ECMO. Double-lumen cannulae were inserted via the jugular approach in 14 patients and via the supraclavicular approach in 6 patients. No cannulation-associated complications but for a single minor bleeding from the insertion site of a supraclavicular double-lumen cannula were recorded. Performance of the extracorporeal circuit was comparable between jugular and supraclavicular groups but for a more pronounced oxygenation effect in the supraclavicular double-lumen group caused by higher blood flows via larger (24 F) cannulae. The supraclavicular approach seems safe and equivalent to jugular cannulation and could serve as a valid alternative.

CD23 surface density on B cells is associated with IgE levels and determines IgE-facilitated allergen uptake, as well as activation of allergen-specific T cells.

BACKGROUND: Increasing evidence suggests that the low-affinity receptor for IgE, CD23, plays an important role in controlling the activity of allergen-specific T cells through IgE-facilitated allergen presentation. OBJECTIVE: We sought to determine the number of CD23 molecules on immune cells in allergic patients and to investigate whether the number of CD23 molecules on antigen-presenting cells is associated with IgE levels and influences allergen uptake and allergen-specific T-cell activation. METHODS: Numbers of CD23 molecules on immune cells of allergic patients were quantified by using flow cytometry with QuantiBRITE beads and compared with total and allergen-specific IgE levels, as well as with allergen-induced immediate skin reactivity. Allergen uptake and allergen-specific T-cell activation in relation to CD23 surface density were determined by using flow cytometry in combination with confocal microscopy and T cells transfected with the T-cell receptor specific for the birch pollen allergen Bet v 1, respectively. Defined IgE-allergen immune complexes were formed with human monoclonal allergen-specific IgE and Bet v 1. RESULTS: In allergic patients the vast majority of CD23 molecules were expressed on naive IgD+ B cells. The density of CD23 molecules on B cells but not the number of CD23+ cells correlated with total IgE levels (RS = 0.53, P = .03) and allergen-induced skin reactions (RS = 0.63, P = .008). Uptake of allergen-IgE complexes into B cells and activation of allergen-specific T cells depended on IgE binding to CD23 and were associated with CD23 surface density. Addition of monoclonal IgE to cultured PBMCs significantly (P = .04) increased CD23 expression on B cells. CONCLUSION: CD23 surface density on B cells of allergic patients is correlated with allergen-specific IgE levels and determines allergen uptake and subsequent activation of T cells.

Relation of Nailfold Capillaries and Autoantibodies to Mortality in Patients With Raynaud Phenomenon.

BACKGROUND: In incipient Raynaud phenomenon, nailfold capillaroscopy and autoantibody tests are obtained to screen for an emerging connective tissue disease. Whether the presence of abnormal nailfold capillaries and autoantibodies are related to mortality in patients with incipient Raynaud phenomenon is not known. METHODS AND RESULTS: In 2958 consecutive patients (78% women, median age 45 years) with incipient Raynaud phenomenon without previously known connective tissue disease, nailfold capillaroscopy and laboratory tests for antinuclear antibodies (ANA) and ANA subsets were obtained at initial presentation. During a median follow-up period of 9.3 years, 227 women (9.9% of female patients) and 129 men (20% of male patients) with Raynaud phenomenon died. In comparison with a demographically matched standard population, survival was poorer in patients with Raynaud phenomenon (log-rank test P<0.0001). In patients with Raynaud phenomenon, mortality was higher in men than in women (P<0.0001, Cox proportional hazards model). In women, the presence of abnormal nailfold capillaries, ANA, and anti-Scl-70 antibodies were related to an increase in all-cause mortality. The conjoint presence of abnormal nailfold capillaries and autoantibodies was associated with the highest mortality rates. In men, abnormal nailfold capillaries, and ANA and ANA subsets, as well, were not related to survival. In both sexes, patients' age and serum creatinine were associated with mortality. CONCLUSIONS: In Raynaud phenomenon, male sex, age, and serum creatinine are related to mortality. Abnormal nailfold capillaries and autoantibodies are associated with an increase in all-cause mortality in female patients, but not in male patients with Raynaud phenomenon.

Human alpha-defensins HNPs-1, -2, and -3 in renal cell carcinoma: influences on tumor cell proliferation.

The alpha-defensins human neutrophil peptides (HNPs)-1, -2, and -3 have been described as cytotoxic peptides with restricted expression in neutrophils and in some lymphocytes. In this study we report that HNPs-1, -2, and -3 are also expressed in renal cell carcinomas (RCCs). Several RCC lines were found to express mRNA as well as the specific peptides of HNP-1, -2, and -3 demonstrated by reverse transcriptase-polymerase chain reaction, mass spectrometric, and flow cytometric analyses. At physiological concentrations HNPs-1, -2, and -3 stimulated cell proliferation of selected RCC lines in vitro but at high concentrations were cytotoxic for all RCC lines tested. As in RCC lines, alpha-defensins were also detected in vivo in malignant epithelial cells of 31 RCC tissues in addition to their expected presence in neutrophils. In most RCC cases randomly, patchy immunostaining of alpha-defensins on epithelial cells surrounding neutrophils was seen, but in six tumors of higher grade malignancy all tumor cells were diffusely stained. Cellular necrosis observed in RCC tissues in association with extensive patches of HNP-1, -2, and -3, seemed to be related to high concentrations of alpha-defensins. The in vitro and in vivo findings suggest that alpha-defensins are frequent peptide constituents of malignant epithelial cells in RCC with a possible direct influence on tumor proliferation.