Insular dysfunction and descending pain inhibition in anorexia nervosa

OBJECTIVE

Reduced perception of pain is a well-established phenomenon in patients with anorexia nervosa (AN). We tested the hypothesis that altered processing of pain within the insula might account for reduced perception of pain.

METHOD

Heat pain thresholds were obtained in nineteen patients with AN and matched controls. Thereafter, a thermode was used to deliver thermal painful stimuli to the right arm during functional magnetic resonance imaging (fMRI) measurements. Stimuli were initiated for 10 s from a baseline resting temperature (32°C) to three different levels (37, 42, 45°C).

RESULTS

Significantly increased heat pain thresholds were observed in patients. A stronger activation during heat pain perception was found in the left posterior insula in controls. In contrast, higher levels of activity were shown in the ipsilateral pons in patients when compared to controls. In patients, we found a significant interrelation between the depression score (Beck depression inventory) and heat pain activations.

CONCLUSION

We suggest that reduced activity in the left posterior insula might contribute to increased pain thresholds in patients, while increased activations in the right anterior insula and pons mirror augmented sympathetic modulation putatively related to amplification of adrenergic descending pain inhibition. In addition, pain thresholds and brain activations were influenced by disease-inherent depressed mood.

Concentration-controlled treatment of lupus nephritis with mycophenolate mofetil

Background:

Mycophenolate mofetil (MMF) has recently been established as a potent drug in maintenance treatment for lupus nephritis. However, there is no consensus on the optimal dosing regimen because of a high inter-individual variability of mycophenolic acid (MPA), the active metabolite of MMF. This retrospective study aimed to investigate the effect of an individualized dosing regimen through concentration-controlled treatment on MPA exposure and renal outcome in patients with lupus nephritis.

Methods:

Sixteen patients with lupus nephritis and treatment with low-dose intravenous cyclophosphamide followed by MMF were included. MPA area under the plasma concentration-time curve from 0 to 12 hours (MPA-AUC0–12) was assessed within a month after MMF initiation. After determination of MPA-AUC0–12, MMF doses were titrated to achieve a target MPA-AUC0–12 of 60–90 mg*h/l. After on average six months, MPA-AUC0–12 measures were repeated to assess the effect of dose adjustment.

Results:

One month after introducing MMF, MPA-AUC0–12 was low and showed a high inter-individual variability. Dose adjustment with a target MPA-AUC0–12 of 60–90 mg*h/l resulted in individualized MMF dosing, significantly higher MPA-AUC0–12 levels, and a non-significant reduction in variability of MPA-AUC0–12. Adverse effects were reported by 37.5% of patients, which resulted in a switch to azathioprine in two patients. There was no significant relationship between the occurrence of adverse effects and MPA-AUC0–12. At 12 months of follow-up 87.5% of patients had achieved either partial (18.7%) or complete (68.8%) remission.

Conclusion:

Concentration-controlled dose adjustments with a target MPA-AUC0–12 of 60–90 mg*h/l was associated with optimized MPA exposure and an excellent renal outcome at 12 months of follow-up in a small sample of SLE patients with lupus nephritis.

Biologically based strategies to augment rotator cuff tears

Lesions of the rotator cuff (RC) are among the most frequent tendon injuries. In spite of the developments in both open and arthroscopic surgery, RC repair still very often fails. In order to reduce the failure rate after surgery, several experimental in vitro and in vivo therapy methods have been developed for biological improvement of the reinsertion. This article provides an overview of the current evidence for augmentation of RC reconstruction with growth factors. Furthermore, potential future therapeutic approaches are discussed. We performed a comprehensive search of the PubMed database using various combinations of the keywords “tendon,” “rotator cuff,” “augmentation,” “growth factor,” “platelet-rich fibrin,” and “platelet-rich plasma” for publications up to 2011. Given the linguistic capabilities of the research team, we considered publications in English, German, French, and Spanish. We excluded literature reviews, case reports, and letters to the editor.

Dutch guidelines for diagnosis and therapy of proliferative lupus nephritis

Proliferative lupus nephritis is a strong predictor of morbidity and mortality in patients with systemic lupus erythematosus. Despite improvements in the management of lupus nephritis, a significant number of the patients do not respond to immunosuppressive therapy and progress to end-stage renal failure. In order to optimise the diagnostic strategy and treatment of patients with proliferative lupus nephritis, guidelines are needed. In this review, the Dutch Working Party on Systemic Lupus Erythematosus provides recommendations regarding four important areas in patients with proliferative lupus nephritis: I) indications for a first renal biopsy, II ) definitions of treatment response, III ) selection of treatment options, and IV) indications for a repeat biopsy.

Geometric phase and nonadiabatic effects in an electronic harmonic oscillator

Steering a quantum harmonic oscillator state along cyclic trajectories leads to a path-dependent geometric phase. Here we describe its experimental observation in an electronic harmonic oscillator. We use a superconducting qubit as a nonlinear probe of the phase, which is otherwise unobservable due to the linearity of the oscillator. We show that the geometric phase is, for a variety of cyclic paths, proportional to the area enclosed in the quadrature plane. At the transition to the nonadiabatic regime, we study corrections to the phase and dephasing of the qubit caused by qubit-resonator entanglement. In particular, we identify parameters for which this dephasing mechanism is negligible even in the nonadiabatic regime. The demonstrated controllability makes our system a versatile tool to study geometric phases in open quantum systems and to investigate their potential for quantum information processing.

Receptor for advanced glycation end products (RAGE) polymorphisms are associated with systemic lupus erythematosus and disease severity in lupus nephritis

OBJECTIVE

Interaction of advanced glycation end products (AGEs) with their receptors (RAGE) plays an important role in inflammation in auto-immune diseases. Several functional polymorphisms of RAGE have been described. In this study we analysed the role of RAGE polymorphisms in disease susceptibility for systemic lupus erythematosus (SLE). In addition, we investigated whether these polymorphisms in SLE are associated with serum levels of soluble RAGE (sRAGE), renal involvement (lupus nephritis (LN)) and its outcome.

METHODS

For this cross-sectional study DNA samples of 97 SLE patients, 114 LN patients and 429 healthy controls (HC) were genotyped for four RAGE polymorphisms: -429 T/C, -374 T/A, 2184 A/G and Gly82Ser. Differences in genotype frequencies and allele frequencies were tested between patients and HCs. In SLE patients, sRAGE was measured by enzyme-linked immunosorbent assay (ELISA). In addition, association of genotypes with sRAGE and disease severity in LN was analysed.

RESULTS

The C allele of -429 T/C, the T allele of -374 T/A and the G allele of 2184 A/G were significantly more prevalent in SLE and LN compared with HC. In LN, the C allele of RAGE -429 T/C, the A allele of -374 T/A and the G allele of RAGE 2184 A/G polymorphism were significantly associated with more proteinuria and worse renal function during the first two years of treatment. No association of genotype with sRAGE was found.

CONCLUSION

RAGE polymorphisms are associated with susceptibility to SLE and LN. In addition, some of these polymorphisms are likely to be associated with disease severity and initial response to treatment in LN.

Mannan-binding lectin mediates renal ischemia/reperfusion injury independent of complement activation

Ischemia/reperfusion injury (IRI) remains a major problem in renal transplantation. Clinical studies have identified that high serum levels of Mannan-binding lectin (MBL), the initiator of the lectin pathway of complement activation, are associated with inferior renal allograft survival. Using a rat model, we identified an entirely novel role for MBL in mediating renal IRI. Therapeutic inhibition of MBL was protective against kidney dysfunction, tubular damage, neutrophil and macrophage accumulation, and expression of proinflammatory cytokines and chemokines. Following reperfusion, exposure of tubular epithelial cells to circulation-derived MBL resulted in internalization of MBL followed by the rapid induction of tubular epithelial cell death. Interestingly, this MBL-mediated tubular injury was completely independent of complement activation since attenuation of complement activation was not protective against renal IRI. Our identification that MBL-mediated cell death precedes complement activation strongly suggests that exposure of epithelial cells to MBL immediately following reperfusion is the primary culprit of tubular injury. In addition, also human tubular epithelial cells in vitro were shown to be susceptible to the cytotoxic effect of human MBL. Taken together, these data reveal a crucial role for MBL in the early pathophysiology of renal IRI and identify MBL as a novel therapeutic target in kidney transplantation.

[Traumatic brain injury in children]

The general practitioner has an important role in the acute management and during the rehabilitation process of children after a traumatic head injury. Latest research shows that sequelae may occur even after a mild head injury without loss of consciousness. Recognizing the warning signs and symptoms after a head injury allows the general practitioner to counsel the child and parents in secondary prevention, particularly in order to avoid any further head injury during the recovery phase. Under the supervision of the general practitioner, a gradual progressive return to the child's everyday activities optimizes the chances of a rapid and complete recovery.

A transgenic approach to identify thyroxine transporter-expressing structures in brain development

Transporters are essential in thyroid hormone metabolism. Thyroxine (T4) is transported by solute carrier organic anion transporter 1c1 (SLCO1C1, OATP14) into the adult brain, where T4 is converted to 3,5,3'-triiodothyronine (T3). In adults, SLCO1C1 expression is found in two brain barrier structures: the blood-brain barrier (BBB) and choroid plexus. However, little is known about how T4 is transported in the developing brain, when the BBB is not yet completely formed. We employed bacterial artificial chromosome recombineering to generate transgenic mice carrying Cre recombinase in the Slco1c1 locus (Slco1c1-Cre mice). In Slco1c1-Cre mice Cre was expressed at the sites that have been previously reported for SLCO1C1 in adults. To trace Cre expression during development, we crossed Slco1c1-Cre transgenic mice with Rosa26 reporter mice. β-galactosidase staining showed Cre activity in neurones of various brain structures, such as cortical layer 2/3 and the hippocampus, suggesting transient Slco1c1 expression during brain development. At embryonic day15, SLCO1C1 was expressed at the same site as TBR2, a marker of neuronal progenitors. Neurones that express SLCO1C1 during their development could be T4 sensitive. In support of this hypothesis, hypothyroxinaemia induced by propylthiouracil treatment of dams decreased the number of β-galactosidase-positive neurones in cortical layer 2/3 of newborn Slco1c1-Cre/Rosa26 mice. In conclusion, by generating Slco1c1-Cre transgenic mice, we demonstrated that SLCO1C1 is expressed in the neuronal cell lineage during brain development. Expression of SLCO1C1 may underlie the extraordinary sensitivity of specific neuronal populations to hypothyroxinaemia.

Illness perceptions in patients with systemic lupus erythematosus and proliferative lupus nephritis

This study investigated the illness perceptions of patients with systemic lupus erythematosus (SLE) and whether perceptions are influenced by type of treatment for proliferative lupus nephritis. In addition, the illness perceptions of SLE patients were compared with those of patients with other chronic illnesses. Thirty-two patients who had experienced at least one episode of proliferative lupus nephritis were included. Patients were treated with either a high or low-dose cyclophosphamide (CYC) regimen (National Institutes of Health [NIH] vs. Euro-Lupus protocol). Illness perceptions were measured with the Brief Illness Perception Questionnaire (B-IPQ) and a drawing assignment. The low-dose CYC group perceived their treatment as more helpful than the high-dose CYC group. In comparison with patients with asthma, SLE patients showed more negative illness perceptions on five of the eight illness perception domains. Drawings of the kidney provided additional information about perceptions of treatment effectiveness, kidney function and patients' understanding of their illness. Drawing characteristics showed associations with perceptions of consequences, identity, concern and personal control. These findings suggest that the type of treatment SLE patients with proliferative lupus nephritis receive may influence perceptions of treatment effectiveness. In addition, patients' drawings reveal perceptions of damage caused by lupus nephritis to the kidneys and the extent of relief provided by treatment. The finding that SLE is experienced as a more severe illness than other chronic illnesses supports the need to more frequently assess and aim to improve psychological functioning in SLE patients.

A randomized cross-over trial comparing single-agents capecitabine (C) and UFT plus leucovorin (LV) in patients (Pts) with advanced colorectal cancer (CRC): Preliminary data of a patient preference study

558

Background: Oral fluoropyrimidines such as C and UFT plus LV (U) are widely used pro-drugs dedicated to the care of CRC. Although their toxicity profile may slightly differ, no direct comparison between these treatments has been done as both molecules are converted into fluorouracil. To help the physicians to choose between C and U, we initiated this randomized cross-over trial aimed to assess patient's preference.

Methods: Pts with advanced CRC received either a first cycle of C (1,250mg/m2 x 2/d for 14 days, q3 wks) or a first cycle of U (UFT 300mg/m2/d plus LV 75 mg/d in 3 divided doses every 8 hrs for 28 days, repeated at 35-day intervals). Patients were randomized to receive C at cycle 1 followed by U (arm A) or U at cycle 1 followed by C (arm B). After 2 cycles, pts were asked which treatment they preferred. Treatment was then continued with the chosen regimen. Preferences rates are presented with 95% confidence intervals and the two groups are compared with the chi-squared test.

Results: 89 pts were enrolled from 10/2005 to 6/2010. Treatment arms were well balanced for baseline characteristics: male 57%; median age 66 years; PS 0-1 81%. Most of the pts were heavily pretreated (0/1/2/ and >2 previous chemotherapy lines: 6/2/15/66). 64 (arm A: 35, arm B: 29)/89 pts received at least 2 cycles of chemotherapy and were evaluable for preference. At cycle 1, 21% and 43% of the pts presented at least 1 severe toxic event with C and U, respectively. Pts with U at cycle 1 presented more likely with severe fatigue and anorexia. There was 1 toxic death under C (gr. 3 diarrhea, gr.4 neutropenia) at cycle 1. Overall, 66% (95%CI: 52-77%) of evaluable pts expressed preference for C, and there was a statistically significant difference between arms A and B (p<0.02) with more pts preferring C in arm A: 79% (95%CI: 61-91%), as compared to arm B: 50% (95%CI: 31-79%).

Conclusions: Pts with advanced CRC preferred C over U, especially when given during the first cycle.

No significant financial relationships to disclose.

Pancreas allograft biopsies with positive c4d staining and anti-donor antibodies related to worse outcome for patients

C4d+ antibody-mediated rejection following pancreas transplantation has not been well characterized. Therefore, we assessed the outcomes of 27 pancreas transplantation patients (28 biopsies), with both C4d staining and donor-specific antibodies (DSA) determined, from a cohort of 257 patients. The median follow-up was 50 (interquartile range [IQR] 8-118) months. Patients were categorized into 3 groups: group 1, patients with minimal or no C4d staining and no DSA (n = 13); group 2, patients with either DSA present but no C4d, diffuse C4d+ and no DSA or focal C4d+ and DSA (n = 6); group 3, patients with diffuse C4d+ staining and DSA (n = 9). Active septal inflammation, acinar inflammation and acinar cell injury/necrosis were significantly more abundant in group 3 than in group 2 (respective p-values: 0.009; 0.033; 0.025) and in group 1 (respective p-values: 0.034; 0.009; 0.002). The overall uncensored pancreas graft survival rate for groups 1, 2 and 3 were 53.3%, 66.7% and 34.6%, respectively (p = 0.044). In conclusion, recipients of pancreas transplants with no C4d or DSA had excellent long-term graft survival in comparison with patients with both C4d+ and DSA present. Hence, C4d should be used as an additional marker in combination with DSA in the evaluation of pancreas transplant biopsies.

Enhanced complement activation is part of the unfavourable cardiovascular risk profile in South Asians

South Asian immigrants in western societies exhibit a high burden of diabetes and subsequent vascular complications. Diabetic vascular complications are associated with vascular inflammation. We hypothesize that enhanced complement activation is involved. Therefore, levels of complement C3 and SC5b-9 - the soluble end product of complement activation - in a group of 200 South Asians were compared with an age- and sex-matched control group of native Caucasians. In addition, the association between complement levels and albuminuria, an indicator of renal damage and a cardiovascular risk marker, was assessed in the diabetic South Asian group. Compared with native Caucasians, South Asians had significantly higher levels of both serum C3 and plasma SC5b-9, even when only non-diabetic South Asians were considered. Diabetic South Asians had significantly higher C3 levels compared with non-diabetic South Asians. In diabetic South Asians, higher levels of SC5b-9 were associated with an increased prevalence of albuminuria (odds ratio 5.4, 95% confidence interval 1.8-15.8). These results suggest that enhanced complement activation is part of the unfavourable cardiovascular risk profile in South Asians.

Mineralocorticoid receptors in control of emotional arousal and fear memory

The stress hormone corticosterone acts via two receptor types in the brain: the mineralocorticoid (MR) and the glucocorticoid receptor (GR). Both receptors are involved in processing of stressful events. A disbalance of MR:GR functions is thought to promote stress-related disorders. Here we studied the effect of stress on emotional and cognitive behaviors in mice with forebrain-specific inactivation of the MR gene (MR(CaMKCre), 4 months old; and control littermates). MR(CaMKCre) mice responded to prior stress (5 min of restraint) with higher arousal and less locomotor activity in an exploration task. A fear conditioning paradigm allowed assessing in one experimental procedure both context- and cue-related fear. During conditioning, MR(CaMKCre) mice expressed more cue-related freezing. During memory test, contextual freezing remained potentiated, while control mice distinguished between cue (more freezing) and context episodes (less freezing) in the second memory test. At this time, plasma corticosterone levels of MR(CaMKCre) mice were 40% higher than in controls. We conclude that control of emotional arousal and adaptive behaviors is lost in the absence of forebrain MR, and thus, anxiety-related responses are and remain augmented. We propose that such a disbalance in MR:GR functions in MR(CaMKCre) mice provides the conditions for an animal model for anxiety-related disorders.

Cell cycle arrest and aberration yield in normal human fibroblasts. I. Effects of X‐rays and 195 MeV u−1C ions

PURPOSE

To examine the relationship between cell proliferation and the expression of chromosomal damage in normal human skin fibroblasts after X-ray and particle irradiation.

MATERIALS AND METHODS

Confluent G0/G1 AG1522B cells were exposed to X-rays or 195MeV u(-1) C ions with a linear energy transfer of 16.6 keV microm(-1) in the dose range 1-4 Gy. Directly after irradiation, cells were reseeded at a low density in medium containing 5-bromo-2'-deoxyuridine. At multiple time points post-irradiation, the cumulative BrdU-labelling index, mitotic index and aberration frequency were measured. Based on these data, the total amount of damage induced within the entire cell population was estimated by means of mathematical analysis.

RESULTS

Both types of radiation exposure exert a pronounced effect on the cell cycle progression of fibroblasts. They result in delayed entry of cells into S-phase and into the first mitosis, and cause a dramatic reduction in mitotic activity. Measurement of chromosomal damage in first-cycle cells at multiple time points post-irradiation shows that the frequencies of aberrant cells and aberrations increase with time up to twofold for the lower doses. However, for the higher doses, this effect is less pronounced or even disappears. When the data for the whole cell population are analysed, it becomes evident that only a few damaged fibroblasts can progress to the first mitosis, a response attributable at least in part to a long-term arrest of injured cells in the initial G0/G1-phase. As observed in other investigations, the effectiveness of 195 MeV u(-1) C ions was similar or slightly higher than X-rays for all endpoints studied leading to a relative biological effectiveness in the range 1.0-1.4.

CONCLUSIONS

Cell cycle arrests affect the aberration yield observable in normal human fibroblasts at mitosis. The data obtained for the cell population as a whole reveal that injured cells are rapidly removed from the mitotically active population through a chronic cell cycle arrest, which is consistent with other studies that indicate that this response is a specific strategy of fibroblasts to minimize the fixation and propagation of genetic alterations.