Emergency lung biopsy: friend or foe of the immunosuppressed child?

An acute pneumonic process in an immunosuppressed child poses a diagnostic and therapeutic challenge. These patients tolerate infection poorly. An open lung biopsy may provide prompt diagnosis. Nevertheless, a beneficial change in therapy that results in survival does not necessarily follow. Fifty-six immunosuppressed children with acute respiratory symptoms and interstitial pulmonary infiltrates underwent lung biopsy from 1974 to 1985. The most common underlying diagnosis was acute lymphocytic leukemia (60%). A specific etiology was determined in 46 (82%). Operative morbidity in 52% included prolonged intubation, recurrent pneumothorax, and hemorrhage. Overall, mortality was 34%. Those patients with solid tumor and those who required postoperative ventilation had a statistically significant higher mortality than all others. We defined biopsy "patient benefit" as follows: (1) the biopsy yielded an etiology for which a change of treatment was required; and (2) the child survived this acute illness. Despite the successful diagnostic results of this procedure, only 13 (23%) of the patients derived clinical benefit. Even though a specific infectious etiology was diagnosed in 39 (69%) patients only ten (18%) of these improved and survived after an appropriate change in therapy. Eight of these had Pneumocystis carinii. One survivor benefited from the treatment of documented radiation pneumonitis. Another was successfully treated for graft v host reaction but this diagnosis also was made by skin biopsy. One half of the biopsies were performed very early in the course of the illness, specifically to exclude Pneumocystis carinii of which we saw a peak incidence in 1978 to 1979.(ABSTRACT TRUNCATED AT 250 WORDS)     

Predictors of diagnosis of child psychiatric disorder in adult–infant social-communicative interaction at 12 months

To establish which social interactive behaviours predict later psychiatric diagnosis, we examined 180 videos of a parent–infant interaction when children were aged one year, from within the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort. Sixty of the videos involved infants who were later diagnosed with a psychiatric disorder at seven years, and 120 were a randomly selected sex-matched control group. Interactive behaviours for both the caregiver and the one year old infant were coded from the videos according to eight holistic categories of interpersonal engagement: Well-being, Contingent Responsiveness, Cooperativeness, Involvement, Activity, Playfulness, Fussiness, and Speech. Lower levels of adult activity and speech in interaction at one year significantly predicted overall diagnosis of child psychiatric disorder.     

Blunt transection of rectus abdominis following seatbelt related trauma with associated small and large bowel injury

INTRODUCTIONClosed rupture of rectus abdominis following seatbelt related trauma is rare.PRESENTATION OF CASEWe present the case of a 45 year old female who presented with closed rupture of the rectus abdominis in conjunction with damage to small bowel mesentery and infarction of small and large bowel following a high velocity road traffic accident. Multiple intestinal resections were required resulting in short bowel syndrome and abdominal wall reconstruction with a porcine collagen mesh. Post-operative complications included intra-abdominal sepsis and an enterocutaneous fistula.DISCUSSIONThe presence of rupture of rectus abdominis muscle secondary to seatbelt injury should raise the suspicion of intra-abdominal injury.CONCLUSIONOur case highlights the need for suspicion, investigation and subsequent surgical management of intra-abdominal injury following identification of this rare consequence of seatbelt trauma.     

Engineering a composite neotrachea with surgical adhesives

Background/Purpose: Reconstructive surgery often is limited by the availability of normal tissue. Tissue engineering provides promise in the development of [ldquo ]artificial tissues.[rdquo ] The purpose of this study was to test the efficacy and viability of the use of a biologic surgical adhesive TISSEEL in combining engineered bronchial epithelium with engineered cartilage. Methods: Using isolated human cells, bronchial epithelium and mature cartilage were engineered. Using a contact adhesive technique, TISSEEL was used to biologically fuse the bronchial epithelium and the cartilage. The fused composite then was supported for 5 days in tissue culture. The mechanical properties of the adhesion were tested, and the construct was studied morphologically to assess viability of the cartilage and the bronchial epithelium. The bronchial epithelium showed a normal cell size (337.2 [mu ]m²) and epithelial thickness (46.47 [mu ]m). Results: TISSEEL was effective in fusing the epithelium to the cartilage. The construct remained viable for 5 days in culture. There was no difference in the dimensions of the bronchial epithelium or the epithelial cells. Mechanical adhesion was achieved. Conclusions: Biologically compatible fibrin glue is an effective surgical adhesive that allows the tissue types to be fused while remaining viable and morphologically accurate. Surgical adhesives may show promise in the development of composite tissue development in the field of bioengineering. J Pediatr Surg 37:1034-1037.     

Longitudinal functional connectivity changes correlate with mood improvement after regular exercise in a dose‐dependent fashion

Exercise increases wellbeing and improves mood. It is however unclear how these mood changes relate to brain function. We conducted a randomized controlled trial investigating resting‐state modifications in healthy adults after an extended period of aerobic physical exercise and their relationship with mood improvements. We aimed to identify novel functional networks whose activity could provide a physiological counterpart to the mood‐related benefits of exercise. Thirty‐eight healthy sedentary volunteers were randomised to either the aerobic exercise group of the study or a control group. Participants in the exercise group attended aerobic sessions with a physiotherapist twice a week for 16 weeks. Resting‐state modifications using magnetic resonance imaging were assessed before and after the programme and related to mood changes. An unbiased approach using graph metrics and network‐based statistics was adopted. Exercise reduced mood disturbance and improved emotional wellbeing. It also induced a decrease in local efficiency in the parahippocampal lobe through strengthening of the functional connections from this structure to the supramarginal gyrus, precentral area, superior temporal gyrus and temporal pole. Changes in mood disturbance following exercise were correlated with those in connectivity between parahippocampal gyrus and superior temporal gyrus as well as with the amount of training. No changes were detected in the control group. In conclusion, connectivity from the parahippocampal gyrus to motor, sensory integration and mood regulation areas was strengthened through exercise. These functional changes might be related to the benefits of regular physical activity on mood.     

Collagen crosslinking and cell density have distinct effects on fibroblast-mediated contraction of collagen gels

Background/purpose: Fibroblasts are actively and dynamically involved in wound healing (dermal regeneration, wound contraction, and scar contracture) and fibrosis. Fibroblast-seeded collagen gels provide an in vitro model for these processes. Over time, fibroblasts will contract the gels, but the mechanisms are not completely understood. This research investigated the influence of cell density and collagen crosslinking on the contraction of fibroblast-populated gels by varying seeding density and blocking the catalyzing enzyme lysyl oxidase, respectively.
Methods: Collagen gels were seeded with fibroblasts at either 3 × 10⁴ or 1 × 10⁵ cells/mL and incubated with or without the lathyrogen β-aminoproprionitrile (BAPN) for 8 days. In all, four experimental groups were analyzed: low cell density control, high cell density control, low density plus BAPN, and high density plus BAPN. Digital images were taken daily and gel area was calculated.
Results: Contraction was dependent on cell concentration, with higher density gels being contracted to a greater extent. BAPN had no effect until after day 2 when it inhibited (high density) or almost completely blocked (low density) the gel contraction. BAPN also reduced total long-term contraction.
Conclusion: The results demonstrated a bimodal nature to fibroblast-mediated gel contraction: a cell density-dependent component, most likely mediated through cellular forces, and a delayed collagen crosslinking component that could be blocked by BAPN. In the long-term, similar contraction rates among the four experimental groups, particularly between the two BAPN groups, implies that the collagen crosslinking effect is discrete and independent of cell density.     

Fas-mediated induction of hepatocyte apoptosis in a neuroblastoma and hepatocyte coculture model.

BACKGROUND: We have previously demonstrated an increase in hepatocyte apoptosis when they are cocultured with neuroblastoma cells. Death receptors in the tumor necrosis factor (TNF) family such as TNFR1 and Fas have been identified as regulators of apoptosis and may be responsible for the altered regulation of apoptosis seen in our coculture model. To evaluate the effects of released factors and remove the potential alterations induced by direct contact, a noncontact coculture system was used to study the interaction between hepatocytes and neuroblastoma cells. METHODS: Human Chang hepatocytes (HC) were plated onto Falcon cell culture inserts with 0.45-micrometer pores in the permeable membrane. Human neuroblastoma cells (NB-IMR-32) were seeded into wells of the Falcon companion plate. After 24 h, inserts containing HC were placed into wells containing NB cells and incubated for 4 days. This provided a coculture environment without actual cellular contact. Immunohistochemical staining for TNFalpha, Fas, and Fas ligand (Fas-L) was performed. Apoptosis was detected via the TUNEL method. Images were analyzed with ImagePro-Plus. Statistical analyses were done with significance determined at P < 0.05. RESULTS: Chang hepatocytes demonstrated a significant increase in the levels of TNF, Fas, and Fas-L when cocultured with neuroblastoma cells (P < 0.005). In addition, the cocultured hepatocytes had a 20-fold increase in the apoptotic rate (P < 0.001). Neuroblastoma cells had no demonstrable level of Fas or TNF when grown alone and in cocultures. Neuroblastoma cells that were grown alone had an elevated level of Fas-L, but this level diminished by 44% when cocultured with hepatocytes (P < 0.001). CONCLUSION: An upregulated TNF/Fas receptor-ligand system may be responsible for increased apoptosis in hepatocytes when cocultured with neuroblastoma. This upregulation may be due to release of neuroblastoma-derived Fas ligand into the media. Tumors may alter the regulation of apoptosis in surrounding tissues via the death receptors.