Netrin Signaling Defines the Regional Border in the Drosophila Visual Center

The brain consists of distinct domains defined by sharp borders. So far, the mechanisms of compartmentalization of developing tissues include cell adhesion, cell repulsion, and cortical tension. These mechanisms are tightly related to molecular machineries at the cell membrane. However, we and others demonstrated that Slit, a chemorepellent, is required to establish the borders in the fly brain. Here, we demonstrate that Netrin, a classic guidance molecule, is also involved in the compartmental subdivision in the fly brain. In Netrin mutants, many cells are intermingled with cells from the adjacent ganglia penetrating the ganglion borders, resulting in disorganized compartmental subdivisions. How do these guidance molecules regulate the compartmentalization? Our mathematical model demonstrates that a simple combination of known guidance properties of Slit and Netrin is sufficient to explain their roles in boundary formation. Our results suggest that Netrin indeed regulates boundary formation in combination with Slit in vivo.

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Netrin regulates boundary formation in combination with Slit in the fly brain

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Dual Netrin functions as attractant and repellent explain boundary formation

Temporal patterning of neurogenesis and neural wiring in the fly visual system

During neural development, a wide variety of neurons are produced in a highly coordinated manner and form complex and highly coordinated neural circuits. Temporal patterning of neuron type specification plays very important roles in orchestrating the production and wiring of neurons. The fly visual system, which is composed of the retina and the optic lobe of the brain, is an outstanding model system to study temporal patterning and wiring of the nervous system. All of the components of the fly visual system are topographically connected, and each ommatidial unit in the retina corresponds to a columnar unit in the optic lobe. In the retina, the wave of differentiation follows the morphogenetic furrow, which progresses in a posterior-to-anterior direction. At the same time, differentiation of the optic lobe also accompanies the wave of differentiation or temporally coordinated neurogenesis. Thus, temporal patterning plays important roles in establishing topographic connections throughout the fly visual system. In this article, we review how neuronal differentiation and connectivity are orchestrated in the fly visual system by temporal patterning mechanisms.

Role of Toll-like Receptor 4 Expressed by Fibroblasts in Allograft Fibrosis in Mouse Orthotopic Tracheal Transplantation

Development of chronic lung allograft dysfunction involves various alloimmune-independent insults including those mediated by Toll-like receptor (TLR) signaling, which is known to activate alloimmune responses. We hypothesized that TLR signaling may also contribute to the activation of fibroblasts and promoting allograft airway fibrosis. Mouse orthotopic tracheal transplants were conducted between major histocompatibility complex (MHC)-mismatched Balb/c donor and wild-type C3H or C3H-derived TLR4 mutant recipients (nonfunctional TLR4). Immunohistochemistry on day 21 showed significantly smaller alpha-smooth muscle actin (α-SMA)-positive areas in TLR4 mutant recipients than wild-type recipients (P = .01). No difference was found for CD3+ T-cell infiltration. Proliferation of alloreactive T cells derived from the recipient spleen showed no difference between TLR4 mutant and wild-type recipients in a mixed lymphocyte reaction. The effect of TLR4 signaling was examined in primary pulmonary fibroblast cultures both with lipopolysaccharide (LPS) and transforming growth factor (TGF)-β1. Stimulation with LPS significantly increased expression of α-SMA mRNA in wild-type fibroblasts cultured with TGF-β1 compared with the control without LPS (P = .001). Taken together, these findings suggest disruption of TLR signaling leads to reduced activation of fibroblasts without affecting T-cell infiltration and proliferation in this model. TLR4-mediated activation of fibroblasts may be a potentially important mechanism of allograft remodeling.

Asymptomatic recurrence detection and cost-effectiveness in urothelial carcinoma

For the management of muscle-invasive bladder cancer or upper tract urothelial carcinoma, the set guidelines recommend regular surveillance after radical cystectomy or radical nephroureterectomy. However, the prognostic benefit of regular oncological surveillance remains controversial in the absence of prospective studies although several retrospective studies with relatively large sample sizes have demonstrated the association between asymptomatic recurrence and better oncological outcomes. Seven out of eight studies reported that patients diagnosed with symptomatic recurrence showed significantly poorer prognosis in comparison to those diagnosed with asymptomatic recurrence. However, potential lead-time and length-time biases prevent the determination of any benefit of regular surveillance. In addition, an optimal surveillance protocol has yet to be established because conventional pathology-based protocols cannot identify the heterogenetic tumor biology of urothelial carcinoma, such as rapid- or slow-growing form of the disease. Several studies suggest that conventional pathology-based surveillance resulted in reduced cost-effectiveness. Recurrence risk-score stratified surveillance protocol including clinical and pathological factors may improve cost-effectiveness. The establishment of optimal risk stratification and surveillance strategies are required to improve the efficacy of regular oncological surveillance. Well-planned prospective studies are necessary to address the prognostic benefit of regular oncological surveillance and shared decision making.

Serum cytokine concentrations, chorioamnionitis and the onset of bronchopulmonary dysplasia in premature infants

OBJECTIVE

To investigate the relationships between serum cytokine concentrations and chorioamnionitis (CAM) and CAM-related bronchopulmonary dysplasia (BPD) in premature infants.

METHODS

Serum was collected at 0 and 7 days after birth from 36 premature infants born at <32 weeks of gestation. We examined the relationships between 30 cytokine concentrations and CAM, BPD, and other perinatal factors.

RESULTS

On day 0, GM-CSF, IL-15, IL-17, IL-2, IL-2R, VEGF, and MIG concentrations were significantly higher in the CAM group (n = 17) than in the non-CAM group (n = 19). These concentrations had decreased by day 7 and were similar in both groups. The IL-12p70 concentration on day 0 was significantly lower in the BPD group (n = 16) than in the non-BPD group (n = 15). BPD incidence was similar between the CAM and non-CAM groups.

CONCLUSIONS

These data support the hypothesis that intrauterine inflammation is not a primary risk factor for BPD. The immunological environment at birth or soon after, rather than intrauterine fetal inflammation (e.g., CAM), is a primary risk factor for BPD onset in preterm infants. Decreased inflammatory responses are particularly relevant, as indicated by the relationship between BPD and low serum IL-12p70 concentrations on day 0.

Azathioprine-induced Agranulocytosis and Severe Alopecia After Kidney Transplantation Associated With a NUDT15 Polymorphism: A Case Report

BACKGROUND

Azathioprine (AZA) is the drug recommended for the continuation of immunosuppressive treatment after renal transplant in women during pregnancy.

CASE REPORT

A 37-year-old Japanese female developed agranulocytosis and severe alopecia after initiation of AZA (50 mg), used as an alternative to mycophenolate mofetil (MMF, 1000 mg) therapy in anticipation of a planned pregnancy. Within 4 days of the initiation of AZA therapy, the patient developed a high fever, leucopenia, and cranial alopecia. Genetic testing revealed a homozygous polymorphism of NUDT15 (rs116855232, NM_018283.3:c.415C>T: p.Arg139Cys), which has previously been identified as a risk factor for AZA-related complications in patients with inflammatory bowel disease.

CONCLUSION

Genetic screening for NUDT15 could contribute to the prevention of serious adverse reactions to AZA and provide the opportunity for personalized medicine. Identification of a safe alternative to MMF during pregnancy after a renal transplant is a problem to be resolved in the future.

Low-Dose Induction Radiotherapy for Stomach Conservation in Patients with Massive Gastric Lymphoma

Low-dose induction radiotherapy was performed in 4 patients with massive gastric lymphoma in order to treat the disease without gastrectomy. Following the radiotherapy, gastric lesions had shrunk considerably without any complications. Standard chemotherapy and/or radiotherapy could then be performed safely, and stomach conservation could be achieved in all 4 patients.

Reliability of Cardiac Output Measurements Using LiDCOrapid and Calibration by Transesophageal Echocardiography With the Continuous Pulmonary Artery Thermodilution Method in Patients Undergoing Aortic Valve Replacement for Aortic Stenosis

OBJECTIVE

This study investigated the accuracy of arterial waveform analysis estimations of cardiac output (CO_AW) and the efficacy of calibrations involving transesophageal echocardiography with continuous cardiac output values obtained using a pulmonary artery catheter.

DESIGN

Prospective cohort study.

SETTING

University hospital operating room.

PARTICIPANTS

Twelve patients undergoing aortic valve replacement for aortic stenosis.

INTERVENTIONS

A pulmonary artery catheter was placed in each patient, and continuous cardiac output was determined using thermodilution principles. LiDCOrapid and transesophageal echocardiography were used to measure CO_AW and to perform the calibration, respectively.

MEASUREMENTS AND MAIN RESULTS

Simultaneous recording of continuous cardiac output and CO_AW values were performed every 20 minutes, after inducing anesthesia. CO_AW was calibrated using transesophageal echocardiography (CO_AW-cal) before and after initiating cardiopulmonary bypass (CPB); the CO_AW and CO_AW-cal were recorded concurrently using a LiDCOrapid monitor. For the pre-CPB dataset (34 data pairs), the mean bias and percentage error were, respectively, 0.10 L/min and 34% for CO_AW versus continuous cardiac output and -0.098 L/min and 27% for CO_AW-cal versus continuous cardiac output. Similarly, for the post-CPB (45 data pairs), the mean bias and percentage error were, respectively, 0.75 L/min and 34% for CO_AW and 0.059 L/min and 26% for CO_AW-cal. A 4-quadrant plot demonstrated an acceptable pre-CPB concordance rate of 93.3% for CO_AW and 93.8% for CO_AW-cal.

CONCLUSION

CO_AW measurements, using LiDCOrapid, have acceptable trending ability pre-CPB. The determination of cardiac output variations, using transesophageal echocardiography, is useful for managing patients undergoing aortic valve replacement for aortic stenosis.

Abstract P1-07-13: Obesity is associated with poor prognosis of Japanese breast cancer, especially in ER positive/HER2 negative subtype, which tendency is prominent

Introduction: Body mass index (BMI) is defined as a poor prognostic factor in breast cancer patients in western countries. Since the percentage of the overweight differs between Asian and western breast cancer patients, we do not know if breast cancer prognosis in Asia is related to obesity, the same as in western countries. Therefore, we have investigated the association between BMI and the prognosis of Japanese breast cancer patients.

Patients and Methods: This study is a retrospective analysis of the 1,924 primary Japanese female breast cancer patients with clinical stage I through III disease to have undergone surgery between January 2004 and December 2013 at the Hokkaido Cancer Center. The data of BMI were at the time of diagnosis, and stratified into 2 groups as non-Obese (BMI &lt; 25 kg/m2), Obese (BMI ≥ 25 kg/m2). The overall survival (OS) and disease-free survival (DFS) were compared between two BMI groups using the Kaplan-Meier method and Cox hazards model.

Results: The number of non-Obese group was 1,353 (70.3%) and Obese group was 571 (29.7%) of the 1,924 patients. Six hundred and thirty two patients were in premenopausal (32.8%), 1,289 were in postmenopausal (67.0%) and 3 were unknown. The median follow-up period was 73 months. Breast cancer recurred in 239 patients (12.2%), and 204 patients died. There were 110 cases of breast cancer-related death, 48 cases of non-breast cancer death, and 46 cases of unknown as the cause of death. Patients in Obese group had shown significantly poorer OS (adjusted hazard ratio (HR) = 1.68, 95% confidence interval (CI) = 0.45 to 0.79) and DFS (HR = 1.46, 95% CI = 1.16 to 1.82). As investigating by subtype analysis, a high BMI in ER positive/HER2 negative patients was associated with a significantly worse OS (HR = 2.04, 95% CI = 1.42 to 2.92) and significantly worse DFS (HR = 1.61, 95% CI = 1.23 to 2.11). On the other hand, there was no significant interaction found between the BMI and OS or DFS in ER negative/HER2 negative patients and HER2 positive patients. Subsequently, when analysis was limited to ER positive HER2 negative, there was a difference in the degree of association between obesity and prognosis due to the difference in menopause status. In premenopausal patients with ER positive/HER2 negative cancer, Obese group had significantly poorer OS (HR = 2.83, 95%CI = 1.32 to 5.88) and significantly poorer DFS (HR = 2.41, 95%CI = 1.41 to 3.99). In postmenopausal patients, Obese group patients had significantly poorer OS (HR = 1.71, 95%CI = 1.11 to 2.58) and poorer DFS (HR = 1.35, 95%CI = 0.98 to 1.86), however. The relevance was not so large compared with that in premenopausal patients.

Conclusion: Among Japanese breast cancer patients, Obese (BMI ≥ 25 kg/m2) was one of poor prognostic factors. Specifically, obesity was associated as an extremely strong prognostic factor in ER positive/HER2 negative premenopausal patients. Since hormone therapy has been practiced in almost all ER positive breast cancers, the relationship between hormonal therapy susceptibility and obesity is noticed not only in western patients but also in Asian patients.

Citation Format: Sato M, Terai S, Tachikawa H, Maeda H, Yamamoto M, Tomioka N, Watanabe K, Takahashi M. Obesity is associated with poor prognosis of Japanese breast cancer, especially in ER positive/HER2 negative subtype, which tendency is prominent [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P1-07-13.

Detecting asymptomatic recurrence after radical nephroureterectomy contributes to better prognosis in patients with upper urinary tract urothelial carcinoma

Background

The prognostic benefit of regular follow-up to detect asymptomatic recurrence after radical nephroureterectomy (RNU) remains unclear. We aimed to assess whether regular follow-up to detect asymptomatic recurrence after RNU improves patient survival.

Materials and Methods

We retrospectively analysed 415 patients who underwent RNU for upper tract urothelial carcinoma at four hospitals between January 1995 and February 2017. All patients had regular follow-up examinations after RNU including urine cytology, blood biochemical tests, and computed tomography. We investigated the first site and date of tumor recurrence. Overall survivals of patients who developed recurrence, stratified by mode of recurrence (asymptomatic vs. symptomatic group), were estimated using the Kaplan-Meier method with the log-rank test. Cox proportional hazards regression analysis was performed using inverse probability of treatment weighting (IPTW) to evaluate the impact of the mode of recurrence on survival.

Results

Of the 415 patients, 108 (26%) experienced disease recurrences after RNU. Of these, 62 (57%) were asymptomatic and 46 (43%) were symptomatic at the time of diagnosis. The most common recurrence site and symptom were lymph nodes and pain, respectively. Overall survival after RNU and time from recurrence to death in the asymptomatic group were significantly longer than that in the symptomatic group. Multivariate Cox regression analysis showed that symptomatic recurrence was an independent risk factor for overall survival after RNU and survival from recurrence to death.

Conclusions

Routine oncological follow-up for detection of asymptomatic recurrence contributes to a better prognosis after RNU.