Endogenous antigen presentation by autoantigen-transfected Epstein-Barr virus-lymphoblastoid cells. I. Generation of human thyroid peroxidase-reactive T cells and their T cell receptor repertoire.

To develop a model for endogenous thyroid autoantigen presentation, we transfected EBV-transformed B lymphoblastoid cell lines (EBV-LCL), established from patients with autoimmune thyroid disease and normal controls, with cDNA for the human thyroid autoantigen thyroid peroxidase (hTPO). hTPO-antigen presentation to patient peripheral blood T cells was demonstrated after stimulation in vitro for 7 d with irradiated hTPO-transfected or untransfected autologous EBV-LCL. Anti-hTPO-reactive T cells were subsequently cloned in the presence of irradiated, autologous hTPO-transfected EBV-LCL and IL-2.10 T cell-cloned lines exhibited specific hTPO-induced proliferation (stimulation indices of 2.1-7.9) towards autologous hTPO-transfected EBV-LCL, and were subjected to human T cell receptor (hTCR) V gene analysis, using the PCR for the detection of V alpha and V beta hTcR gene families. The results indicated a preferential use of hTCR V alpha 1 and/or V alpha 3 in 9 of the 10 lines. In contrast, hTCR V beta gene family use was more variable. These data demonstrate a model for the endogenous presentation of human thyroid peroxidase in the absence of other thyroid specific antigens. The high frequency of antigen-specific T cells obtained from PBMC using this technique will facilitate further studies at both the functional and hTCR V gene level.     

Critical issues on opioids in chronic non-cancer pain: an epidemiological study

The aim of the study was epidemiologically to evaluate the long-term effects of opioids on pain relief, quality of life and functional capacity in long-term/chronic non-cancer pain. The study was based on data from the 2000 Danish Health and Morbidity Survey. As part of a representative National random sample of 16,684 individuals (>16 years of age), 10,066 took part in an interview and completed a self-administered questionnaire. Cancer patients were excluded. The interview and the self-administered questionnaire included questions on chronic/long-lasting pain (>6 months), health-related quality of life (SF-36), use of the health care system, functional capabilities, satisfaction with medical pain treatment and regular or continuous use of medications. Participants reporting pain were divided into opioid and non-opioid users. The analyses were adjusted for age, gender, concomitant use of anxiolytics and antidepressants and pain intensity. Pain relief, quality of life and functional capacity among opioid users were compared with non-opioid users. Opioid usage was significantly associated with reporting of moderate/severe or very severe pain, poor self-rated health, not being engaged in employment, higher use of the health care system, and a negative influence on quality of life as registered in all items in SF-36. Because of the cross-sectional nature causative relationships cannot be ascertained. However, it is remarkable that opioid treatment of long-term/chronic non-cancer pain does not seem to fulfil any of the key outcome opioid treatment goals: pain relief, improved quality of life and improved functional capacity.     

Iterative reconstruction reduces abdominal CT dose

Objective

In medical imaging, lowering radiation dose from computed tomography scanning, without reducing diagnostic performance is a desired achievement. Iterative image reconstruction may be one tool to achieve dose reduction. This study reports the diagnostic performance using a blending of 50% statistical iterative reconstruction (ASIR) and filtered back projection reconstruction (FBP) compared to standard FBP image reconstruction at different dose levels for liver phantom examinations.

Methods

An anthropomorphic liver phantom was scanned at 250, 185, 155, 140, 120 and 100 mA s, on a 64-slice GE Lightspeed VCT scanner. All scans were reconstructed with ASIR and FBP. Four readers evaluated independently on a 5-point scale 21 images, each containing 32 test sectors. In total 672 areas were assessed. ROC analysis was used to evaluate the differences.

Results

There was a difference in AUC between the 250 mA s FBP images and the 120 and 100 mA s FBP images. ASIR reconstruction gave a significantly higher diagnostic performance compared to standard reconstruction at 100 mA s.

Conclusion

A blending of 50–90% ASIR and FBP may improve image quality of low dose CT examinations of the liver, and thus give a potential for reducing radiation dose.     

Separating the left cardiac ventricle from the atrium in short axis MR images using the equation of the atrioventricular plane

Short axis (SA) images obtained from cardiac magnetic resonance imaging are used to advantage in the calculation of important clinical parameters such as the ejection fraction and stroke volume (SV). A prerequisite for these calculations is the separation of the left ventricle and the left atrium. When only using the information seen in the SA images this separation can be a source of error due to the through-plane motion of the basal part of the left ventricle. In this study a method is proposed where the separation of the left ventricle and the atrium is performed by identifying the intersections of the atrioventricular plane in the SA images. The equation of the atrioventricular plane was determined in both systole and diastole using long axis and four chamber image views. Stroke volumes were measured in 20 patients using SA images where the endocardium had been delineated. The SV obtained using the new method was compared with quantitative flow measurements and the conventional technique for calculation of SV from SA images, respectively. The agreement of SV was, according to Bland-Altman analysis, 2.0 ml (95% CI -12.0 to 15.9 ml) in comparison with the flow measurements and 2.2 ml (95% CI -9.2 to 13.6 ml) compared to the conventional method. Inter- and intra-observer variability, when using the new proposed method, was small. This study shows that the identification of the left atrioventricular plane in SA images can be used in the separation of the left atrium and ventricle.     

Cobalamin status and its biochemical markers methylmalonic acid and homocysteine in different age groups from 4 days to 19 years

BACKGROUND: Recent data indicate that cobalamin and folate status, including the metabolic markers methylmalonic acid (MMA) and total homocysteine (tHcy), undergo marked changes during childhood, particularly during the first year. METHODS: Serum cobalamin, serum and whole-blood folate, and plasma MMA and tHcy were determined in a cross-sectional study of 700 children, ages 4 days to 19 years. RESULTS: During the first 6 months, serum cobalamin was lower than and plasma MMA, tHcy, and serum folate were higher than the concentrations detected in the other age groups. In infants 6 weeks to 6 months of age, median MMA and tHcy concentrations were >0.78 and >75 micro mol/L, respectively. In older children (>6 months), serum cobalamin peaked at 3-7 years and then decreased, median plasma MMA remained low (<0.26 micro mol/L), median plasma tHcy was low (<6 micro mol/L) and increased from the age of 7 years on, and serum folate gradually decreased. Plasma MMA was inversely associated with cobalamin (r = -0.4) in both age groups, but across the whole range of cobalamin concentrations, MMA was markedly higher in infants (< or =6 months) than in older children. Plasma tHcy showed a strong negative correlation to cobalamin (r = -0.52) but not to serum folate in infants < or =6 months. In older children, tHcy showed the expected association with both cobalamin (r = -0.48) and folate (r = -0.51). CONCLUSIONS: In infants 6 weeks to 6 months, concentrations of the metabolic markers MMA and tHcy were higher than in the other age groups and strongly correlated to cobalamin, whereas in older children, both makers showed correlations to cobalamin and folate concentrations documented in adults. Whether this metabolic profile in infants is explained by impaired cobalamin status, which in turn may have long-term effects on psychomotor development, remains to be addressed in intervention studies.     

Neutrophil gelatinase-associated lipocalin in adult septic patients with and without acute kidney injury

Purpose

To study the impact of inflammation/sepsis on the concentrations of neutrophil gelatinase-associated lipocalin (NGAL) in plasma and urine in adult intensive care unit (ICU) patients and to estimate the predictive properties of NGAL in plasma and urine for early detection of acute kidney injury (AKI) in patients with septic shock.

Methods

Sixty-five patients admitted to the general ICU at the Karolinska University Hospital Solna, Sweden, with normal plasma creatinine were assessed for eligibility. Twenty-seven patients with systemic inflammatory response syndrome (SIRS), severe sepsis, or septic shock without AKI and 18 patients with septic shock and concomitant AKI were included in the final analysis. Plasma and urine were analyzed twice daily for plasma NGAL (pNGAL), C-reactive protein (CRP), procalcitonin, myeloperoxidase, plasma cystatin C, plasma creatinine, urine NGAL (uNGAL), urine cystatin C, and urine α1-microglobulin.

Results

Of the 45 patients, 40 had elevated peak levels of pNGAL. Peak levels of pNGAL were not significantly different between septic shock patients with and without AKI. Peak levels of uNGAL were below the upper reference limit in all but four patients without AKI. uNGAL was a good predictor (area under ROC 0.86) whereas pNGAL was a poor predictor (area under ROC 0.67) for AKI within the next 12 h in patients with septic shock.

Conclusions

pNGAL is raised in patients with SIRS, severe sepsis, and septic shock and should be used with caution as a marker of AKI in ICU patients with septic shock. uNGAL is more useful in predicting AKI as the levels are not elevated in septic patients without AKI.     

Improvement in glycemic control over 11 years in patients monitored for diabetes in one county.

BACKGROUND: Hemoglobin A(1c) (HbA(1c)) has been used in controlled trials for the last 10 years but has never been evaluated in clinical practice as an effective parameter for clinical outcome. We investigated the trend for glycemic control over 11 years in one county of 350,000 citizens. METHODS: We studied 226,382 HbA(1c-DCCT-aligned) from 39,455 patients in whom routine monitoring for diabetes was initiated in 1993, 1996, or 2001. The trend in glycemic control was investigated in groups by probit plots, and in individual patients by target plots. RESULTS: From 1993 to 2001, the number of HbA(1c) measurements increased three-fold. The number of new monitoring series increased from 0.22% to 0.27% of the county population, and the number of patients monitored using HbA(1c) as a proxy for diabetes increased from 0.5% to 1.5%. A proportional reduction in high HbA(1c) concentrations of 5% was identified in the 1993 group, compared to 15% in the 1996 group, and 20% in the 2001 group. The percentage of patients with diabetic first HbA(1c) experiencing normalization increased from 8% to 30% for males and from 9% to 24% for females (1993-2001). The percentage of HbA(1c) concentrations that were not normalized decreased from 78% to 53% for males and from 83% to 59% for females (1993-2001). The median HbA(1c) at initiation of monitoring decreased from 8.7% in 1993 to 7.5% in 2001 (p < 10(-5)). The number of normal first HbA(1c) results in monitoring series increased from 7% to 17% for males and from 8% to 22% for females. Up to 10% of subjects developed diabetic concentrations during monitoring. CONCLUSION: On average, patients with diabetic first HbA(1c) concentrations (> or =6.62%) showed an improvement in glycemic control from 5% in 1993 to 20% in 2001. High concentrations were easiest to reduce. In patients with originally diabetic HbA(1c) levels, 66% on average showed improved glycemic control in the 2001 series compared to 50% in the 1993 series. An average of 6% (1993) vs. 9% (2001) with originally normal HbA(1c) levels showed an upward trend inHbA(1c) levels. Median HbA(1c) at initiation of monitoring decreased from 8.7% in 1993 to 7.5% in 2001 (p < 10(-5)). The incidence of new cases was constant.     

Residual substance P levels after capsaicin treatment correlate with tendon repair

The aim of the study was to assess healing after capsaicin‐induced substance P (SP) depletion during rat Achilles tendon repair by biomechanical testing. Capsaicin treatment reduced the concentrations of SP by ～60% and calcitonin gene‐related peptide by ～40% as compared with the control group, as assessed by radioimmunoassay in the dorsal root ganglia, at 1 and 4 weeks post‐tendon rupture. Also, the peripheral neuronal presence of SP and calcitonin gene‐related peptide, as assessed by immunohistochemistry, was lower at both weeks 1 and 4. The decreased peripheral neuronal presence of SP at week 1 correlated with the corresponding levels in the dorsal root ganglia (r = 0.54, p = 0.018). The reduced presence of SP/calcitonin gene‐related peptide after capsaicin treatment was verified by a decreased sensitivity to painful mechanical and thermal stimuli (p < 0.05). Correlation analyses between individual residual SP levels and biomechanical tissue properties were performed because of differences in failure mode between the groups and high individual variations in the SP levels after capsaicin treatment. Thus, the residual SP levels in the dorsal root ganglia correlated with transverse area, ultimate tensile strength, and stress at failure (r = 0.39, p = 0.036; r = 0.53, p = 0.005; and r = 0.43, p = 0.023, respectively). Furthermore, individual pain sensitivity at week 2 correlated with peripheral occurrence of SP and was correlated with tensile strength and stress at failure (r = 0.89, p = 0.006 and r = 0.78, p = 0.015) at week 4. In conclusion, rats with higher residual SP levels after capsaicin‐induced neuropathy develop improved tensile strength and stress at failure in the healing of Achilles tendon.