A fronto-insular-parietal network for the sense of body ownership

Neuropsychological disturbances in the sense of limb ownership provide unique opportunities to study the neurocognitive basis of body ownership. Previous small sample studies that showed discrete cortical lesions cannot explain why multisensory, affective, and cognitive manipulations alter disownership symptoms. We tested the novel hypothesis that disturbances in the sense of limb ownership would be associated not only with discrete cortical lesions but also with disconnections of white-matter tracts supporting specific functional networks. We drew on an advanced lesion-analysis and Bayesian statistics approach in 49 right-hemisphere patients (23 with and 26 without limb disownership). Our results reveal that disturbances in the sense of ownership are associated with lesions in the supramarginal gyrus and disconnections of a fronto-insular-parietal network, involving the frontal-insular and frontal inferior longitudinal tracts, confirming previous disconnection hypotheses. Together with previous behavioral and neuroanatomical results, these findings lead us to propose that the sense of body ownership involves the convergence of bottom-up, multisensory integration, and top-down monitoring of sensory salience based on contextual demands.

Role of PD-L1 in heart transplant rejection

Background

Acute cellular rejection remains a major cause of morbidity after heart transplantation with up to 30% of patients experiencing at least one rejection episode during the first year. Unfortunately, the mechanism underling rejection remains poorly understood and the gold standard for diagnosing rejection remains frequent cardiac biopsy for rejection surveillance – a process that is both invasive and costly.

Purpose

PD-L1 is a co-inhibitory transmembrane protein that interacts with PD-1 on T cells to inhibit T cell activation. Endothelial PD-L1 expression in the heart has been shown in mouse models to play a key role in attenuating immune-mediated cardiac disease like myocarditis. Recent data that anti-PD-1 and anti-PD-L1 therapy can lead to myocarditis further supports a role for PD-1/PD-L1 signaling in cardiovascular homeostasis. We hypothesize that PD-L1 expression correlates with rejection severity.

Methods

Endomyocardial biopsy from a cohort of 19 heart transplant patients were analyzed for PD-L1 expression using immunohistochemistry and image analysis with HALO software. Each patient had biopsies corresponding to 0R, 1R, and 2R grades of rejection (n=57) and thus each patient served as their own internal control. Detailed clinical data was also collected on these patients from the electronic medical record.

Results

Average PD-L1 levels associated with 0R (n=19), 1R (n=21), and 2R (n=17) rejection were 1.54, 9.15, and 18.90 respectively (P<0.001). In patients who were treated for 2R rejection with increased immunosuppression (n=9), PD-L1 levels decreased from an average of 21.72 before treatment to an average of 5.64 after treatment (P<0.05). A multiple regression was run to see if PD-L1 level was associated with right heart pressures, EKG intervals, echo data, or common lab values. Accounting for age, race, and sex, it was found that PD-L1 was significantly associated with PA pressure (P<0.01, beta = 0.45), PCW pressure (P<0.01, beta = 0.42), and BNP (P<0.01, beta = 0.55).

Conclusions

Upregulation of PD-L1 in the heart is strongly associated with severity of cellular rejection after heart transplantation. Successful treatment of rejection with immunosuppression decreases PD-L1 levels. These data suggest that PD-L1 is a potential biomarker for heart transplant rejection. Further correlation of PD-L1 levels with signs of right heart strain (increased PA and PCW pressure) and systolic dysfunction (BNP) supports a clinical picture of PD-L1 as a useful biomarker for detecting both cellular rejection and reversal of rejection after treatment.

Cohort identification and results

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): National Institutes of Health grants R56 HL141466 and R01 HL141466

Understanding the influence of 24-hour movement behaviours on the health and development of preschool children from low-income South African settings: the SUNRISE pilot study

Background

The International Study of Movement Behaviours in the Early Years, SUNRISE, was initiated to assess the extent to which young children meet movement behaviour guidelines (physical activity, sedentary behaviour, screen time, sleep).

Objective

The South African SUNRISE pilot study assessed movement behaviours in preschool children from two low-income settings, and associations between these movement behaviours, adiposity, motor skills and executive function (EF).

Methods

Preschool child/parent pairs (n = 89) were recruited from preschools in urban Soweto and rural Sweetwaters. Height and weight were measured to assess adiposity. Physical activity was assessed using accelerometers while sedentary behaviour, screen time and sleep were assessed via parent report. Fine and gross motor development were measured using the Ages and Stages Questionnaire-3, and EF was assessed using the Early Years Toolbox.

Results

The proportion of children meeting the physical activity guideline was 84%, 66% met the sleep guideline, 48% met the screen time guideline, and 26% met all three guidelines. Rural children were more active, but spent more time on screens compared to urban children. Most children were on track for gross (96%) and fine motor (73%) development, and mean EF scores were in the expected range for all EF measures. EF was negatively associated with screen time, and gross motor skills were positively associated with physical activity.

Conclusion

The South African SUNRISE study contributes to the growing literature on 24-hour movement behaviours in SA preschool children, and highlights that these behaviours require attention in this age group.

Serogroups, and drug resistance of nontyphoidal Salmonella in symptomatic patients with community-acquired diarrhea and chicken meat samples in Tehran

BACKGROUND

Salmonella is considered as a main cause of community-acquired diarrhea in humans, however, sources of the multi-drug resistant (MDR) strains and their link with the disease are not well known.

AIMS

This study aimed to investigate the frequency, serogroup diversity, and antimicrobial susceptibility patterns of Salmonella strains in poultry meat and stool samples of patients with community acquired diarrhea in Tehran.

METHODS

We compared the frequency of non-typhoidal Salmonella serogroups, the similarities of their resistance patterns to 10 antimicrobial compounds, the prevalence of extended spectrum β-lactamase (ESBL) and ampicillinase C (AmpC) genetic determinants, and class 1 and 2 integrons in 100 chicken meat and 400 stool samples of symptomatic patients in Tehran during June 2018 to March 2019.

RESULTS

Salmonella was isolated from 75% and 5.5% of the chicken meats and human stool samples, respectively. The chicken meat isolates mainly belonged to serogroup C (88%, 66/75), while the human stool isolates were mainly related to serogroup D (59.1%, 13/22). The MDR phenotype and the most common rates of resistance to antibiotics, including tetracycline, trimethoprim/sulfamethoxazole (TS) and azithromycin, were detected in 4.5% and 45.3%, 59% and 13.6%, 43% and 9.1%, 42% and 9.1% of the human stool and chicken meat samples, respectively. Carriage of bla _CTX, bla _SHV, and bla _PER genes in the meat isolate with ESBL resistance phenotype and bla _ACC, bla _FOX, and bla _CMY-2 among the 7 meat strains with AmpC resistance phenotype was not confirmed using polymerase chain reaction (PCR). High prevalence of class 1 and 2 integrons was characterized and showed a correlation with resistance to TS and chloramphenicol.

CONCLUSION

These findings showed a lack of association between chicken meats and human isolates due to discrepancy between the characterized serogroups and resistance phenotypes.

Impact of early postoperative platelet count on volumetric liver gain and perioperative outcomes after major liver resection

Background

Although perioperative platelet count has been associated with postoperative morbidity and mortality, its impact on liver regeneration has not been examined directly. This study sought to determine the impact of platelet count on liver regeneration after major liver resection using cross-sectional imaging volumetric assessment.

Methods

Patients who underwent major liver resection between 2004 and 2015 and had available data on immediate postoperative platelet count, as well as preoperative and postoperative CT images, were identified retrospectively. Resected liver volume was subtracted from total liver volume (TLV) to define postoperative remnant liver volume (RLVp). The liver regeneration index was defined as the relative increase in liver volume within 2 months ((RLV2m – RLVp)/RLVp, where RLV2m is the remnant liver volume around 2 months after surgery). The association between platelet count, liver regeneration and outcomes was assessed.

Results

A total of 99 patients met the inclusion criteria. Overall, 25 patients (25 per cent) had a low platelet count (less than 150 × 109/l), whereas 74 had a normal–high platelet count (at least 150 × 109/l). Despite having comparable clinicopathological characteristics and RLVp/TLV at surgery (P = 0·903), the relative increase in liver volume within 2 months was considerably lower in the low-platelet group (3·9 versus 16·5 per cent; P = 0·043). Patients with a low platelet count had an increased risk of postoperative complications (72 versus 38 per cent; P = 0·003), longer hospital stay (8 versus 6 days; P = 0·004) and worse median overall survival (24·5 versus 67·3 months; P = 0·005) than those with a normal or high platelet count.

Conclusion

After major liver resection, a low postoperative platelet count was associated with inhibited liver regeneration, as well as worse short- and long-term outcomes. Immediate postoperative platelet count may be an early indicator to identify patients at increased risk of worse outcomes.

Präoperative und palliative Embolisation des Nierenzellkarzinoms: Nachsorge von 49 Patienten

PURPOSE

To evaluate the influence of preoperative and palliative embolization of renal cell carcinomas on survival, intra- and post-operative procedures, and symptom control for palliative and preoperative indications.

MATERIALS AND METHODS

56 patients who underwent renal cell carcinoma embolization from 1981 to 1999 were included in this retrospective study.

RESULTS

24 women and 32 men were included (mean age 59.4 years). Complete follow-up data was available for 49 patients. 42 patients underwent preoperative embolization at different tumor stages (pT1: 1 patient, pT2: 6, pT3 a: 4, pT3 b: 19, pT3 c: 2, pT4: 5). 14 patients underwent palliative embolization (T1: 0 patients, T2: 5, T3: 4, T4: 4). Indications for preoperative embolization were bleeding of the renal tumor in 6 cases -- non-recurrent bleeding reported, flank pain in 4 patients -- 3 of 4 patients had no further symptoms, recurrent tumor embolization in 1 patient, and 2 patients who wanted to be treated without symptoms. The mean survival time of preoperative embolized patients was 3.1 +/- 5.11 years with a 5-year survival rate of 50 %. The mean survival time of palliative embolized patients was 0.67 +/- 0.76 years with initial metastases (n = 7) and 2.33 +/- 2.40 without metastases (n = 6).

CONCLUSION

Palliative embolization of renal cell carcinomas is a safe therapeutic method to treat advanced renal cell carcinomas allowing control of symptoms such as hematuria and flank pain in more than 90 % of our cases. Preoperative embolization yields a patient survival time comparable to that of patients at earlier tumor stages and is dependent on the metastases.