Influence of exclusive breastfeeding on hippocampal structure,satiety responsiveness,and weight status

Longer exclusive breastfeeding duration has been associated with differences in neural development, better satiety responsiveness, and decreased risk for childhood obesity. Given hippocampus sensitivity to diet and potential role in the integration of satiety signals, hippocampus may play a role in these relationships. We conducted a secondary analysis of 149, 7–11‐year‐olds (73 males) who participated in one of five studies that assessed neural responses to food cues. Hippocampal grey matter volume was extracted from structural scans using CAT12, weight status was assessed using age‐ and sex‐adjusted body mass index (%BMI_p85), and parents reported exclusive breastfeeding duration and satiety responsiveness (Children''s Eating Behaviour Questionnaire). Separate path models for left and right hippocampus tested: (1) the direct effect of exclusive breastfeeding on satiety responsiveness and its indirect effect through hippocampal grey matter volume; (2) the direct effect of hippocampal grey matter volume on %BMI_p85 and its indirect effect through satiety responsiveness. %BMI_p85 was adjusted for maternal education, yearly income, and premature birth while hippocampal grey matter volume was adjusted for total intercranial volume, age, and study from which data were extracted. Longer exclusive breastfeeding duration was associated with greater bilateral hippocampal grey matter volumes. In addition, better satiety responsiveness and greater left hippocampal grey matter volume were both associated with lower %BMI_p85. However, hippocampal grey matter volumes were not associated with satiety responsiveness. Although no relationship was found between breastfeeding and child weight status, these results highlight the potential impact of exclusive breastfeeding duration on the hippocampal structure.     

Time Course for the Hazard of Radiation-induced Pneumonitis Death in Mice

The form of the hazard function for radiation-induced pneumonitis death in mice was investigated. ‘Hazard’ refers to the instantaneous failure rate at a specified time, conditional upon non-failure to that time. Thus, the hazard function describes the time profile for the risk of pneumonitis death among still-surviving subjects. Single-dose lethality data from nine previously published studies involving irradiation of the lung were combined. Sufficient data were then available to estimate the hazard for eight different dose groups (dose range 12–15 Gy). The results of this study suggest that there are multiple distinct peaks in the hazard function for radiation pneumonitis, corresponding to distinct waves of death separated by an average interval of 33 days. The times of the peak hazards are dose dependent, with the peak hazards occurring earlier after larger doses, and the values of the hazards at the peaks are also dose dependent, with larger doses corresponding to a greater risk of death. The implications of a multiply-peaked hazard function for the possible mechanisms of response to whole-lung irradiation are discussed.     

Neuromuscular choristoma presenting with unilateral limb hypoplasia in a 3‐year‐old boy

Introduction: Neuromuscular choristomas (NMCs) are rare benign peripheral nerve lesions in which skeletal muscle tissue is admixed with nerve fascicles. Methods: We describe a case of sciatic nerve NMC presenting with unilateral limb hypoplasia, monoparesis, and equinovarus contracture in a pediatric patient. We outline the unique clinical presentation and diagnostic work‐up for our patient, including electromyographic and imaging studies. Results: MRI revealed fusiform enlargement of the sciatic nerve, <50% intralesional fat, and signal characteristics similar to those of muscle tissue. Ultrasound was utilized to characterize atrophy and fatty infiltration of affected muscles. The patient was treated conservatively with a customized physical therapy program and lower limb orthosis. Conclusions: Emerging diagnostic criteria are highlighted with the goal of distinguishing NMCs from more common peripheral nerve lesions. This can have important clinical consequences, as unnecessary biopsies are associated with aggressive fibromatosis, a potentially devastating complication. Muscle Nerve 54 : 797–801, 2016     

The impact of training under different visual-spatial conditions on reverse-alignment laparoscopic skills development

Background  

Circumstances may arise during laparoscopic procedures in which alignment of the laparoscope and the instruments is off by 180°, creating a mirror image of the operative field. It has been shown that task performance is degraded under these reverse-alignment conditions, and that the magnitude of performance impairment is directly related to laparoscopic experience and skill. The aim of this study was to determine if reverse-alignment surgical skills could be developed through training.     

Serial MRI and clinical assessment of cyclops lesions

Purpose

‘Clinical cyclops syndrome’ is associated with pain and a palpable ‘clunk’ at terminal extension with the loss of full extension. The aims of this prospective controlled study were: (1) to assess whether the minimal debridement of the ACL stump and notch is associated with an increased incidence of clinical cyclops lesions, (2) to look at the incidence and natural history of ‘MRI cyclops’ lesions using serial MRI’s and (3) to assess whether ‘MRI cyclops’ lesions are associated with the loss of extension.

Methods

Forty-eight patients were randomized for ACL reconstruction into standard (23) and minimal debridement (24) techniques. One patient was excluded from the study. All patients underwent MR scanning postoperatively at 2, 6 and 12 months, together with the clinical assessment using a KT-1000 arthrometer and International Knee Documentation Committee evaluation. All observations were made by investigators blinded to the surgical technique.

Results

There was no statistical difference in the incidence of cyclops lesions between the two groups (n.s.). The overall incidence of cyclops lesions was 46.8 % (22 of 47). The natural history is variable with some getting larger, smaller or remaining static in size. Of patients with cyclops lesions, 17 patients (77 %) had cyclops lesions in the setting of full extension. Five patients (23 %) had loss of extension at 12 months with no MRI cyclops detected at 2 months.

Conclusions

The natural history is variable; although once present, the majority of cyclops remain static or regress in size. The onset of cyclops lesions is usually between 6- and 12-month post-ACL reconstruction. Minimal debridement does not lead to an increased incidence of clinical cyclops lesions. The authors conclude that loss of extension is multi-factorial, and there is a discrepancy between what we term ‘MRI cyclops’ and true ‘clinical cyclops’.

Level of evidence

Case–control study, Level II.