Ex vivo response to mucosal bacteria and muramyl dipeptide in inflammatory bowel disease

AIM To evaluate how mucosal bacteria impact on the spontaneous and muramyl dipeptide(MDP)-induced inflammation in Crohn's disease(CD) and ulcerative colitis(UC).METHODS Colonic mucosal biopsies were collected from children with active or remissive CD, UC and controls. Two tissue samples were taken from inflamed mucosal segments(in patients with active disease) or from noninflamed mucosa [in patients in remission or in healthy controls(HC)]. Experiments were performed in the presence or absence of antibiotics, to assess whether the disease-associated microbiota can modulate the cytokine response ex vivo. For this purpose, each specimen was half-cut to compare spontaneous and MDP-induced inflammation in the presence of live bacteria(LB) or antibiotics. After 24 h of culture, an array of 17 cytokines was assessed in supernatants. Statistical analyses were performed to find significant differences in single cytokines or in patterns of cytokine response in the different groups. RESULTS We demonstrated that subjects with CD display a spontaneous production of inflammatory cytokines including granulocyte-colony stimulating factor(G-CSF), interleukin(IL) 6, IL8, IL10 and IL12, that was not significantly influenced by the addition of antibiotics. UC specimens also displayed a trend of increased spontaneous secretion of several cytokines, which however was not significant due to broader variability among patients. After the addition of antibiotics, spontaneous IL8 secretion was significantly higher in UC than in controls. In HC, a trend towards the weakening of spontaneous IL8 production was observed in the presence of live mucosal bacteria with respect to the presence of antibiotics. In contrast, in the presence of LB UC showed an increasing trend of spontaneous IL8 production, while MDP stimulation resulted in lower IL8 production in the presence of antibiotics. We also showed that subjects with CD seem to have a lowered production of IL8 in response to MDP in the presence of LB. Only with the addition of antibiotics, likely reducing the contribution of LB, multivariate statistical analysis could identify the combination of measures of G-CSF, tumor necrosis factor alpha, IL4 and IL17 as a good discriminator between CD and UC.CONCLUSION We showed that the presence of LB or antibiotics can significantly influence the inflammatory response ex vivo in inflammatory bowel diseases.     

Restless legs syndrome triggered by heart surgery

This report presents the case of a 9-year-old child with a familial history of restless legs syndrome who began to complain of restless legs syndrome symptoms after heart surgery. Hypotheses on the potential interactions between genetic and environmental factors in the development of her restless legs syndrome are discussed. Increasing evidence supports reduced brain iron in the pathophysiology of idiopathic restless legs syndrome. It is possible that the child inherited a compromised brain and peripheral iron regulation, which predisposed her to restless legs syndrome. The interaction between her dysfunctional iron management and her intraoperatory blood loss may have led to a significant decrease in brain iron, triggering restless legs syndrome symptoms. Other factors, such as immobilization and sleep deprivation after surgery, may have contributed to trigger the restless legs syndrome symptoms. If confirmed by further evidence, this patient suggests the need to carefully monitor for restless legs syndrome symptoms in young surgical patients who present with a familial history of restless legs syndrome.     

Subcortical Plasticity Following Perceptual Learning in a Pitch Discrimination Task

Practice can lead to dramatic improvements in the discrimination of auditory stimuli. In this study, we investigated changes of the frequency-following response (FFR), a subcortical component of the auditory evoked potentials, after a period of pitch discrimination training. Twenty-seven adult listeners were trained for 10 h on a pitch discrimination task using one of three different complex tone stimuli. One had a static pitch contour, one had a rising pitch contour, and one had a falling pitch contour. Behavioral measures of pitch discrimination and FFRs for all the stimuli were measured before and after the training phase for these participants, as well as for an untrained control group (n = 12). Trained participants showed significant improvements in pitch discrimination compared to the control group for all three trained stimuli. These improvements were partly specific for stimuli with the same pitch modulation (dynamic vs. static) and with the same pitch trajectory (rising vs. falling) as the trained stimulus. Also, the robustness of FFR neural phase locking to the sound envelope increased significantly more in trained participants compared to the control group for the static and rising contour, but not for the falling contour. Changes in FFR strength were partly specific for stimuli with the same pitch modulation (dynamic vs. static) of the trained stimulus. Changes in FFR strength, however, were not specific for stimuli with the same pitch trajectory (rising vs. falling) as the trained stimulus. These findings indicate that even relatively low-level processes in the mature auditory system are subject to experience-related change.     

Polydimethylsiloxane (macroplastique®) injection for vesicoureteral reflux in duplex ureters: a comparison with single renal systems

Objective

VUR in patients with a duplex system (DS) is often treated by open surgery. The aim of this study was to evaluate the efficacy of subureteric polydimethylsiloxane (Macroplastique^®) injection (SMING) in the management of VUR in duplex and single (SS) renal systems.

Patients and methods

Fifteen children (24 refluxing renal units) with VUR in DS underwent SMING. VUR was more frequent in the lower moiety. VUR was graded moderate/severe in 88% of renal units. There was a history of urinary tract infections in 40% of cases. The outcome for DS patients was compared with 44 children (60 refluxing renal units) with moderate/severe VUR in SS.

Results

The VUR resolution/improvement rate was 88% in DS and 95% in SS patients. Ureteric reimplantation was required because of recurrent VUR in 13% and 7% of DS and SS groups, respectively. Transient ureteral obstruction was observed in 1/15 and 5/44 patients. Two required double-J ureteric stenting for 3 months.

Conclusion

SMING seems an effective treatment for VUR in both DS and SS patients, even in severe cases. The complication rate does not significantly differ between the two groups.     

The Auditory Enhancement Effect is Not Reflected in the 80-Hz Auditory Steady-State Response

The perceptual salience of a target tone presented in a multitone background is increased by the presentation of a precursor sound consisting of the multitone background alone. It has been proposed that this “enhancement” phenomenon results from an effective amplification of the neural response to the target tone. In this study, we tested this hypothesis in humans, by comparing the auditory steady-state response (ASSR) to a target tone that was enhanced by a precursor sound with the ASSR to a target tone that was not enhanced. In order to record neural responses originating in the brainstem, the ASSR was elicited by amplitude modulating the target tone at a frequency close to 80 Hz. The results did not show evidence of an amplified neural response to enhanced tones. In a control condition, we measured the ASSR to a target tone that, instead of being perceptually enhanced by a precursor sound, was acoustically increased in level. This level increase matched the magnitude of enhancement estimated psychophysically with a forward masking paradigm in a previous experimental phase. We found that the ASSR to the tone acoustically increased in level was significantly greater than the ASSR to the tone enhanced by the precursor sound. Overall, our results suggest that the enhancement effect cannot be explained by an amplified neural response at the level of the brainstem. However, an alternative possibility is that brainstem neurons with enhanced responses do not contribute to the scalp-recorded ASSR.     

Intraoperative radiotherapy for breast cancer

Postoperative radiotherapy, which forms part of breast-conserving therapy, may not need to encompass the whole breast. Apart from the consumption of huge resources and patients' time, postoperative radiotherapy deters many women from receiving the benefits of breast-conserving surgery, forcing them to choose a mastectomy instead. If radiotherapy could be given in the operating theatre immediately after surgery, many of these disadvantages could be overcome. One striking fact about local recurrence after breast-conserving surgery is that most occurs in the area of breast immediately next to the primary tumour; this is despite the finding that two-thirds of mastectomy samples have microscopic tumours distributed throughout the breast, even when radiotherapy is omitted. Thus, only the area adjacent to the tumour may need treatment with radiotherapy. On the basis of this premise, clinical scientists have used new technology to administer radiotherapy to the area at greatest risk of local recurrence, with the aim of completing the whole local treatment in one sitting. In this review, we have elaborated on the rationale and different methods of delivery of intraoperative radiotherapy. If this approach is validated by the results of current randomised trials, it could save time, money, and breasts.     

Hemophagocytic lymphohistiocytosis is a sign of poor outcome in pediatric Epstein‐Barr virus‐associated post‐transplant lymphoproliferative disease after allogeneic hematopoietic stem cell transplantation

EBV‐related PTLD developing after HSCT is a potentially life‐threatening disease. HLH is uncommon after allogeneic HSCT. Data on outcome of patients with PTLD and concomitant HLH after allogeneic HSCT are limited. In this retrospective study, we collected demographic, clinical, laboratory, and outcome data for 408 patients who underwent allogeneic HSCT from 2006 to 2015. Graft source included CB (n = 135; 33.1%), PBSCs (n = 34; 8.3%), and BM (n = 239; 58.6%). Eight out of 408 patients (2%) developed EBV‐PTLD with a median age at HSCT of 5.9 years (range: 2.3‐17.3). All eight patients received ATG as part of the conditioning regimen. Graft source was PBSC in three patients (37.5%), BM in four patients (50%), and CB in one patient (12.5%). Donors were matched unrelated in five patients (62.5%) and matched sibling in three patients (37.5%). Seven out of eight patients developed EBV‐PTLD within the first 100‐day post‐HSCT. Lymph node biopsy revealed early lesions in three patients, polymorphic in three patients, and monomorphic PTLD in two patients. Three patients (37.5%) died within 1 month of EBV‐PTLD diagnosis. All deceased patients developed HLH manifestations with two of them meeting HLH diagnostic criteria and one having an incomplete workup. PTLD after allogeneic HSCT with manifestations of HLH is associated with high mortality. Early identification and treatment of EBV‐PTLD seems imperative to control the disease, especially if signs of HLH are evolving.     

Lewis lung carcinoma (3LL) cells treated in vitro with ultraviolet radiation show reduced metastatic ability due to an augmented immunogenicity

The metastatic ability of 3LL tumor following in vitro irradiation with ultraviolet (u.v.) light was studied. Tumor cells were exposed to two courses of u.v.-irradiation (3LL × 2u.v. cells) and after two weeks of culture they were inoculated intravenously (i.v.) into syngeneic mice. These cells produced significantly fewer pulmonary metastases than the untreated population. In addition, intrafootpad (i.f.p.) injections of 3LL × 2u.v. cells into immunocompetent animals induced tumors only in 40 per cent of recipients. Interestingly, in normal mice with progressively growing 3LL × 2u.v. tumors, the formation of spontaneous pulmonary metastases was prevented, whereas metastatic foci were observed in 70 per cent of the nude recipients. The metastatic properties of u.v.-treated tumor cells were further analysed by using individual clones with varying immunogenicity. We found that variants with augmented immunogenicity also showed a parallel decrease in metastatic potential. Studies on H-2 antigen expression in different clones revealed that immunogenic and low metastatic variants expressed levels of H-2 antigens higher than the tumorigenic and metastatic clones. Finally, by using cyclophosphamide (Cy) treatment and adoptive transfer of immune spleen cells we were able to eradicate macroscopic 3LL pulmonary metastasis. These results demonstrate that the decrease of metastatic ability in u.v.-treated cells was mainly due to an increase in their immunogenicity and H-2 antigen expression.