Safety and feasibility of robotic surgery for colon cancer patients with previous abdominal surgery: a propensity score-matching analysis

Robotic surgery is widely used in gastrointestinal surgery. While the application of robotic surgery for colon cancer patients with previous abdominal surgery (PAS) remains controversial for the fear of intra-abdominal adhesions. This study was aimed to evaluate the safety and feasibility of robotic colectomy for patients with PAS. The medical records of colon cancer patients who underwent robotic surgery at our hospital from June 2015 to August 2020 were extracted and analyzed. Propensity score-matching (PSM) analysis was implemented to minimize selection bias. We compared perioperative outcomes and postoperative complications between the patients with PAS or with no PAS (NPAS). A total of 79 patients (PAS group) and 348 patients (NPAS group) were included in our study. After PSM, 79 patients of PAS group and 79 patients of NPAS group were selected for further analysis. We did not find statistical difference in operative time, estimated blood loss, lymph nodes retrieved, length of hospital stay and hospital costs between the two groups. No difference was noted in the incidence of postoperative complications, conversion to open surgery and mortality between the two groups. According to the results of multivariate analysis, PAS was not identified as risk factor for postoperative complications. Left hemicolectomy and perioperative transfusion were associated with postoperative complications. PAS did not negatively affect the outcomes of robotic colectomy. After individually preoperative assessment, robotic surgery could be performed feasibly and safely for colon cancer patients with PAS.

Interdigitation of Radiation Earlier in the Multimodal Treatment of Patients with Lymphoma: The Effect on Opiate Analgesic Requirements

PURPOSE/OBJECTIVE(S)

Delay in radiation therapy (RT) as part of multimodality therapy in Hodgkin (HL) and non-Hodgkin lymphoma (NHL) is associated with worse pain scores. In a heterogeneous cohort of lymphoma patients, we hypothesize that interdigitating RT before fewer (versus more) lines of chemotherapy (C) will be associated with lower opiate analgesic requirement.

MATERIALS/METHODS

From 2009-2019, patients with HL or NHL received palliative (36.5%) or definitive (63.3%) RT at a single institution. An IRB approved database with baseline treatment/disease characteristics, including oral morphine equivalent (OME) requirement, was reviewed. OME was recorded for a) 3-month period prior to RT, b) the month during RT, and c) 3 months after RT. Post-RT change in OME was calculated as the difference in "b" and "c" such that greater or less OME use post-RT was defined as positive or negative value respectively. We performed one-tailed t-test analyses to determine differences in OME during RT between different cohorts. Correlations between baseline characteristics and OME were performed using Spearman correlations, controlling for lymphoma subtype, stage, tumor volume, relapsed/refractory disease, duration of radiation and bulky disease.

RESULTS

Of 180 patients, 57.8% had NHL, 40.6% were stage IV and 29.4% had bulky disease. At median of 19 days [6-80] from diagnosis, 74% of patients received C with a median of 2 lines [1-4] before RT. The median interval from diagnosis to RT was 11 months [4-36]. Pearson correlation showed a negative association between time from diagnosis to RT and postRT OME in the definitive cohort (R2 = 0.42, F = 4.54, p = 0.002) such that the longer the time to RT, the larger the decrease in OME postRT as compared to during RT. T-test showed higher mean OME during RT for those receiving > 2 lines of C preRT (148.3mg) as compared to those receiving ≤ 2 lines before RT (51.5mg, p = 0.02). In patients receiving definitive RT, the difference remained significant: those receiving >2 lines of C had higher OME during RT as compared to those receiving ≤ 2 lines (207.5mg versus 48.3mg, p = 0.02). The difference in mean OME for patients receiving >2 C lines versus ≤ 2 lines was not significantly different in the palliative cohort (75.6 vs 60.6, p = 0.33). OME use during RT was also found to be higher in patients with bulky disease as compared to non-bulky disease (175.7 versus 52.0, p = 0.04).

CONCLUSION

In our single-center experience, patients who received >2 lines of C prior to RT were found to have a significantly higher mean OME requirement during RT. In patients receiving definitive RT, longer time to receipt of RT was found to be associated with a larger decrease in OME post-RT, likely related to starting with a higher OME. Interdigitation of RT early on, prior to the 3rd line of chemotherapy, may help reduce pain and improve quality of life.

Safety and feasibility of robotic surgery for old rectal cancer patients

Robotic surgery is widely utilized for rectal cancer. Older patients are associated with comorbidity and diminished cardiopulmonary reserve, resulting in uncertainty and reluctance to perform robotic surgery in older patients. The aim of the study was to assess the safety and feasibility of robotic surgery in older rectal cancer patients. We collected the data of patients diagnosed with rectal cancer and operated at our hospital from May 2015 to January 2021. All patients undergoing robotic surgery were classified into two groups: the old group (≥ 70 years) and young group (< 70 years). Perioperative outcomes were analyzed and compared between the two groups. Risk factors related to postoperative complications were also explored. A total of old N = 114 and young N = 324 rectal patients were enrolled in our study. Older patients were prone to exhibit comorbidity than the young and had lower body mass index and higher scores of American Society of Anesthesiologists than the young. No statistical difference was found in operative time, estimated blood loss, lymph nodes retrieved, tumor size, pathological TNM stage, hospital stay after surgery and total hospital cost between the two groups. The incidence of postoperative complications did not show difference between the two groups. On multivariate analyses, male sex and longer operative time could predict postoperative complications, whereas old age was not an independent factor for postoperative complications. After careful preoperative evaluation, robotic surgery is a technically feasible and safe procedure for older rectal cancer patients.

Could immune-related hepatitis rapidly progress to immune-related cirrhosis?

BACKGROUND

Immune-related hepatitis is one of the prevalent adverse events associated with immunotherapy, especially immune checkpoint inhibitors (ICIs). For patients without a history of liver disease, autoimmune disease, or alcohol consumption, it is not clear whether immune-related hepatitis could rapid progress to immune-related cirrhosis.

CASE REPORT

We report the case of a 54-year-old female with stage IIIB primary pulmonary lymphoepithelioma-like carcinoma (PLELC) diagnosed with immune-related hepatitis. After 15 months, a liver biopsy demonstrated the rapid progression of liver cirrhosis although systematic corticosteroid administration.

CONCLUSIONS

Long-term immune activation caused by ICIs may exacerbate the process of cirrhosis. Great attention should be paid to the rapid progression to liver cirrhosis of immune-related hepatitis in the clinic.

Genome-wide association study for reproduction-related traits in Chinese domestic goose

1. This study measured six reproduction traits in a Sichuan white goose population (209 individuals), including fertility, qualified egg rate, plasma concentrations of progesterone (P), follicle-stimulating hormone (FSH), prolactin (PRL) and oestrogen (E2).2. Whole-genome resequencing data from the same goose population (209 individuals) were used in a genome-wide association study (GWAS) utilising a mixed linear model to investigate the genes and genetic markers associated with reproduction traits. The frequency of the selected SNPs and haplotypes were determined using the Matrix-Assisted Laser Desorption Ionisation Time-Of-Flight Mass Spectrometry (MALDI-TOF MS) method.3. In total, 42 SNPs significantly associated with these traits were identified. A haplotype block was constructed based on five SNPs that were significantly associated with qualified egg rate, with individuals having the haplotype CCTTAAGGAA having the lowest qualified egg rate.4. In conclusion, these results provided potential markers for marker-assisted selection to improve goose reproductive performance and a basis for elucidating the genetics of goose reproduction.

Surgical and oncological outcomes of robotic- versus laparoscopic-assisted distal gastrectomy with D2 lymphadenectomy for advanced gastric cancer: a propensity score‑matched analysis of 1164 patients

BACKGROUND

Studies on surgical outcomes after robotic surgery are increasing; however, long-term oncological results of studies comparing robotic-assisted distal gastrectomy (RADG) versus laparoscopic-assisted distal gastrectomy (LADG) for advanced gastric cancer (AGC) are still limited. This study aimed to assess the surgical and oncological outcomes of RADG and LADG for the treatment of AGC.

METHODS

A total of 1164 consecutive AGC patients undergoing RADG or LADG were enrolled between January 2015 and October 2021. Propensity score-matched (PSM) analysis was performed to minimize selection bias. The perioperative and oncological outcomes between the two groups were compared.

RESULTS

Patient's characteristics were comparable between the two groups after PSM. RADG group represented a longer operative time (205.2 ± 43.1 vs 185.3 ± 42.8 min, P < 0.001), less operative blood loss (139.3 ± 97.8 vs 167.3 ± 134.2 ml, P < 0.001), greater retrieved lymph nodes (LNs) number (31.4 ± 12.1 vs 29.4 ± 12.3, P = 0.015), more retrieved LNs in the supra-pancreatic areas (13.4 ± 5.0 vs 11.4 ± 5.1, P < 0.001), and higher medical costs (13,608 ± 4326 vs 10,925 ± US $3925, P < 0.001) than LADG group. The overall complication rate was 13.7% in the RADG group and 16.6% in the LADG group, respectively; the difference was not significantly different (P = 0.242). In the subgroup analysis, the benefits of RADG were more evident in high BMI patients. Moreover, the 3-year overall survival (75.5% vs 73.1%, P = 0.471) and 3-year disease-free survival (72.9% vs 71.4%, P = 0.763) were similar between the two groups.

CONCLUSION

RADG appears to be a safe and feasible procedure and could serve as an alternative treatment for AGC in experienced centers.

Learning Curve of Robotic-Assisted Total Mesorectal Excision for Rectal Cancer

Background

Although some studies have assessed the learning curve of robotic-assisted total mesorectal excision for rectal cancer, most studies included limited sample sizes, no study used postoperative complications as an independent variable to analyze the learning curve of robotic rectal surgery, and no study evaluated the influence of the learning curve on long-term oncologic outcomes.

Methods

Clinical data on consecutive patients who underwent robotic-assisted total mesorectal excision for rectal cancer by a single surgeon between January 2015 and December 2018 at the First Affiliated Hospital of Nanchang University were retrospectively collected. The cumulative sum (CUSUM) and risk-adjusted cumulative sum (RA-CUSUM) were used to visualize the learning curve of operation time and postoperative complications (CD ≥ grade II). Comparisons of clinical outcomes at different learning phases analyzed by RA-CUSUM were performed after propensity score matching.

Results

A total of 389 consecutive patients were included in the analysis. The numbers of patients needed to overcome the learning curves of operation time and postoperative complications of robotic-assisted laparoscopic surgery for rectal cancer were 34 and 36, respectively. The learning process was divided into two phases based on RA-CUSUM: the learning phase (1st-36th cases) and the mastery phase (37th-389th cases). Before matching, the mastery phase had more patients with older age, lower tumor location, and neoadjuvant therapy. After matching, the two phases exhibited similar characteristics. The operation time, intraoperative blood loss, postoperative hospital stay, and postoperative complications in the mastery phase were reduced compared with the learning phase, with a median follow-up of 35 months, and the long-term oncologic outcomes were not significantly different between the two phases.

Conclusions

An experienced laparoscopic surgeon initially implements robotic-assisted total mesorectal excision for rectal cancer, surgical outcomes improved after 36 cases, and the learning curve seemingly did not have an obvious impact on long-term oncologic outcomes.

Male urogenital function after robot-assisted and laparoscopic total mesorectal excision for rectal cancer: a prospective cohort study

Background

Urogenital dysfunction is recognized as a serious complication affecting patient quality of life after rectal cancer surgery to treat rectal cancer; however, the studies focus on the urogenital function after robot-assisted rectal cancer surgery compared to laparoscopic surgery are limited.

Methods

Male patients undergoing robotic total mesorectal excision (R-TME) or laparoscopic total mesorectal excision (L-TME) were prospectively enrolled. The International Prostate Symptom Score (IPSS) and the five-item version of the International Index of Erectile Function (IIEF-5) scale were used to compare the urogenital function of the two groups preoperatively and 3, 6, and 12 months postoperatively.

Results

Eighty-nine patients who planned to undergo R-TME and L-TME were prospectively enrolled; 77 patients of these patients (86.5%) completed all questionnaires at all time points and were thus included in the final analysis. Of the included patients, 38 underwent R-TME and 39 underwent L-TME. There was no significant difference in age, BMI, American Society of Anesthesiologists (ASA) score, tumor location, neoadjuvant therapy, operation method, postoperative pathological results and adjuvant therapy between the two groups. Preoperative urogenital function was similar in both groups; however, the IPSS was significantly lower in R-TME patients than that in T-TME patients at 6 months and 12 months [(7.82 ± 2.25 vs. 9.95 ± 3.01, P = 0.006; 7.62 ± 2.5 vs. 9.12 ± 2.64, P = 0.012)]. IIEF-5 scores decreased 3 months after R-TME and L-TME surgery (14.87 ± 3.27 vs. 13.92 ± 3.62, p = 0.231) and then gradually increased; at 12 months, IIEF-5 scores were comparable to those at baseline in both groups. IIEF-5 scores were higher in R-TME patients than those in L-TME patients at 6 months (18.55 ± 3.45 vs. 16.75 ± 3.26, P = 0.021), but there was no significant difference between the two groups at 12 months (21.22 ± 3.06 vs. 19.95 ± 3.03, P = 0.071).

Conclusions

The robotic approach for TME was associated with more rapid restoration of male urogenital function than the laparoscopic approach.

Whole-genome sequencing reveals breed-differential CNVs between Tongcheng and Large White pigs

Large phenotypic differences have been observed between Tongcheng and Large White pigs. However, little is known about their genetic basis. This study performed a genome-wide comparison of CNVs between Tongcheng and Large White pigs using genome sequencing data. By combining the advantages of three different strategies (read depth, paired-end mapping and split read), we detected in total 18 687 CNVs that covered approximately 3.5% of the pig genome length for Tongcheng and Large White pigs. We identified 1864 breed-stratified CNVs (top 10%) by performing V_ST statistics. Functional enrichment analyses for genes located in breed-stratified CNVs were found to be involved in pigmentation, behavior, immune system and reproductive processes, which coincide with phenotypic differences between the two breeds. Using a systematic analysis of the genome and transcriptome data, we further identified four novel breed-differential CNVs on the functional genes (disease-resistant, DCUN1D2 and SPARCL1; lipid metabolism, PLEKHA2 and SLCO1A2). Subsequent PCR validation confirmed their accurate breakpoint positions in 33 Tongcheng pigs and 33 Large White pigs. This study provides essential information on differential CNVs for further research on the genetic basis of phenotypic differences between Tongcheng and Large White pigs.

Short- and long-term outcomes for transvaginal specimen extraction versus minilaparotomy after robotic anterior resection for colorectal cancer: a mono-institution retrospective study

BACKGROUND

Colorectal cancer resection surgery with transvaginal specimen extraction is becoming increasingly accepted and used by surgeons. However, few publications on robotic anterior sigmoid colon and rectal cancer resection with transvaginal specimen extraction (TVSE) have been reported, and a clinical outcome comparison between conventional robotic minilaparotomy (LAP) and transvaginal specimen extraction in anterior sigmoid colon and rectal cancer resection has not been performed. The current study compared the short- and long-term outcomes of TVSE and LAP for sigmoid colon cancer and rectal cancer in a mono-institution.

METHODS

From December 2014 to October 2018, 45 patients who underwent TVSE and 45 patients who underwent LAP matched by tumor location, tumor stage, body mass index (BMI), American Society of Anesthesiologists (ASA) classification, gender, and age at the same period were included in the current study. The short- and long-term outcomes of TVSE and LAP were discussed.

RESULTS

No significant differences were found in patient characteristics. For the short-term outcomes, the operative time in the TVSE group was longer than that in the LAP group, and the postoperative pain and additional analgesia were lower in the TVSE group. Patients in the TVSE group required slightly less time to pass first flatus. There were no significant differences in overall complications, time to regular diet, length of hospital stay after surgery, estimated blood loss, or pathological outcomes. For long-term outcomes, the 3-year overall survival (94.9% vs. 91.7%, p = 0.702) and 3-year disease-free survival (88.4% vs. 86.2%, p = 0.758) were comparable between the two groups.

CONCLUSION

The robotic TVSE is safe and feasible in selected sigmoid/upper rectal cancer patients with tumor diameter < 5 cm. This approach has slightly better short-term outcomes in terms of less postoperative pain and less analgesic requirements without any significant difference in long-term outcomes.

miR-152 promotes spinal cord injury recovery via c-jun amino terminal kinase pathway

OBJECTIVE

The aim of this research is to explore the possible role of miR-152 in spinal cord injury and its underlying mechanism.

MATERIALS AND METHODS

After a mouse model of spinal cord injury (SCI) was developed, Real Time-quantitative Polymerase Chain Reaction (RT-qPCR) was used to detect the expression of miR-152 and c-jun in the mouse. In addition, the expression levels of interleukin-1b (IL-1b), interleukin-18 (IL-18) and tumor necrosis factor-α (TNF-α) were detected by enzyme-linked immunosorbent assay (ELISA). Subsequently, miR-152 was overexpressed and the levels of inflammation and c-jun after spinal cord injury were detected by Western blot. Furthermore, the grip strength of double forelimb, left forelimb or right forelimb of the mice was detected using a grip force test after miR-152 was overexpressed in the injured area of each group.

RESULTS

By constructing a mouse model of spinal cord injury, we found that the expression of miR-152 in the injured area decreased with time; meanwhile, the inflammatory relative genes including IL-1b, IL18, TNF-α, and c-jun were significantly increased. However, miR-152 overexpression significantly reduced the levels of inflammation genes as well as the expression of c-jun. Besides, the strength of the forelimbs in the spinal cord injury mice was restored.

CONCLUSIONS

MiR-152 could inhibit inflammatory responses and promote the recovery of the spinal cord injury through the c-jun N-terminal kinase pathway and it can be a target molecular for treating spinal cord injury.

[Clinicopathological and molecular features of pulmonary enteric adenocarcinoma]

Objective: To investigate the clinicopathological and molecular characteristics of pulmonary enteric adenocarcinoma (PEAC). Methods: The clinical and pathological data of 19 cases of PEAC in the Affiliated Cancer Hospital of Zhengzhou University were retrospectively collected from 2015 to 2019. Immunohistochemistry (IHC) was used to detect the relevant immunophenotypes, amplification refractory mutation system (ARMS) and fluorescence in situ hybridization (FISH) were used to detect the expression of EGFR, KRAS and ALK genes. The patients were followed up, and the relevant literature was reviewed and analyzed. Results: There were 19 cases, including 10 males and 9 females, with a mean age of 58 years (range 33-71 years). Microscopically, the tumors showed moderately to highly differentiated adenoid and/or papillary growth patterns. The tumor cells were highly columnar and sometimes showed pseudostratification. Inflammatory necrosis and scattered nuclear fragmentation were seen in some glandular lumens. IHC showed variable expression of CK7 (19/19), TTF1 (8/19), Napsin A (6/19), villin (17/19), CK20 (16/19) and CDX2 (10/19). Molecular testing showed KRAS mutation in nine cases (9/19), EGFR mutation in one case (1/19), and positive ALK split signal in one case (1/19). In the literature, the reported mutation rate of KRAS in PEAC was much higher than that of EGFR and ALK. All 19 cases underwent surgical resection and 11 cases were subjected to chemotherapy or radiotherapy. Conclusions: PEAC is a rare variant of invasive pulmonary adenocarcinoma, and has similar histological and cytological features to that of colorectal adenocarcinoma. However, detailed medical history, histologic heterogeneity, an IHC combination of CK7(+)/villin(+) and high KRAS mutation rate are the key points of diagnosis. The prognosis needs long-term follow-up and big data statistics.

Molecular cloning of the goose GnRH gene and identification of GnRH polymorphisms associated with laying traits

1. Egg-laying traits are important economic characteristics in goose production (Anser cygnoides). The gene GnRH, which encodes gonadotropin-releasing hormone, is a strong candidate gene for egg-laying traits in avian species. 2. In this study, a 3520 bp genomic sequence and a 279 bp mRNA sequence for GnRH, which encoded 92 amino acids, were determined. The GnRH DNA sequence contains four exons and three introns, and the DNA and deduced amino acid sequences were highly conserved across mammals (human, macaque, cow, and sheep) and avians (chicken, fulmar and quail). 3. Using a direct sequencing method, 46 single nucleotide polymorphisms (SNPs) were identified in the GnRH genomic sequence that were shared between two Sichuan White goose populations (217 and 208 individuals). Furthermore, 44 haplotypes were constructed using a sliding window approach. Association analysis between the SNPs and haplotypes and egg-laying traits showed that 10 SNPs affected the first egg weight, average egg weight, egg number at 48 weeks and egg number at 64 weeks. 4. These results lay the foundation for further studies of the function of GnRH in geese and provide a theoretical basis for marker-assisted selection of egg-laying traits in the Sichuan white goose population.

HER2 exon 20 insertions in non-small-cell lung cancer are sensitive to the irreversible pan-HER receptor tyrosine kinase inhibitor pyrotinib

BACKGROUND

Effective targeted therapy for non-small-cell lung cancer (NSCLC) patients with human epidermal growth factor receptor 2 (HER2) mutations remains an unmet need. This study investigated the antitumor effect of an irreversible pan-HER receptor tyrosine kinase inhibitor, pyrotinib.

PATIENTS AND METHODS

Using patient-derived organoids and xenografts established from an HER2-A775_G776YVMA-inserted advanced lung adenocarcinoma patient sample, we investigated the antitumor activity of pyrotinib. Preliminary safety and efficacy of pyrotinib in 15 HER2-mutant NSCLC patients in a phase II clinical trial are also presented.

RESULTS

Pyrotinib showed significant growth inhibition of organoids relative to afatinib in vitro (P = 0.0038). In the PDX model, pyrotinib showed a superior antitumor effect than afatinib (P = 0.0471) and T-DM1 (P = 0.0138). Mice treated with pyrotinib displayed significant tumor burden reduction (mean tumor volume, -52.2%). In contrast, afatinib (25.4%) and T-DM1 (10.9%) showed no obvious reduction. Moreover, pyrotinib showed a robust ability to inhibit pHER2, pERK and pAkt. In the phase II cohort of 15 patients with HER2-mutant NSCLC, pyrotinib 400 mg resulted in a objective response rate of 53.3% and a median progression-free survival of 6.4 months.

CONCLUSION

Pyrotinib showed activity against NSCLC with HER2 exon 20 mutations in both patient-derived organoids and a PDX model. In the clinical trial, pyrotinib showed promising efficacy.

CLINICAL TRIAL REGISTRATION

NCT02535507.

The direct effects of gonadotropin-releasing hormone on proliferation of granulosa cells and development of follicles in goose

1. The study objectives were to determine the direct effects of gonadotropin-releasing hormone (GnRH) on the proliferation of ovarian granulosa cells (GCs) and the development of follicles in geese (Anser cygnoides) by colorimetry and ethynyl-2'-deoxyuridine (EdU) cell proliferation assays, in which primary GCs were treated with different concentrations of GnRH agonist (alarelin acetate) and an antagonist (cetrorelix acetate). Differently expressed genes (DEGs) were identified by RNA-sequencing and validated by quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blotting. 2. The EdU assays showed that the proliferation of GCs was affected by the GnRH agonist and antagonist in a dose-dependent manner. The effect of treatment on cell proliferation was statistically significant at the concentrations of 10^-5 mol/l alarelin and 1 mg/l cetrorelix acetate. A total of 134 DEGs (76 downregulated and 58 upregulated for alarelin treatment) and 226 DEGs (90 downregulated and 136 upregulated for cetrorelix) were identified by RNA-sequencing analysis, respectively. Enrichment analysis indicated that DEGs were enriched in the GO terms of cell-cell signalling and cell junctions. The pathways that regulate the development of follicles were identified, including the biological progress of cAMP accumulation, ovulation cycle and vasculature that are essential to follicular selection. 3. The results suggested that GnRH might directly regulate GC proliferation via autocrine or paracrine pathways related to cell junctions. In particular, it was confirmed that the mRNA and protein expression levels of the oestrogen receptor 2 (ESR2) gene, a negative transcription factor involved in follicular maturation and ovulation, were affected by GnRH agonist or antagonist in GCs. 4. In conclusion, GnRH might play an important role in follicular development by changing the expression of genes that participate in cAMP accumulation, ovulation cycle and cell junctions in ovarian GCs.

Absence of Quantum-Confined Stark Effect in GaN Quantum Disks Embedded in (Al,Ga)N Nanowires Grown by Molecular Beam Epitaxy

Several of the key issues of planar (Al,Ga)N-based deep-ultraviolet light-emitting diodes could potentially be overcome by utilizing nanowire heterostructures, exhibiting high structural perfection, and improved light extraction. Here, we study the spontaneous emission of GaN/(Al,Ga)N nanowire ensembles grown on Si(111) by plasma-assisted molecular beam epitaxy. The nanowires contain single GaN quantum disks embedded in long (Al,Ga)N nanowire segments essential for efficient light extraction. These quantum disks are found to exhibit intense light emission at unexpectedly high energies, namely, significantly above the GaN bandgap, and almost independent of the disk thickness. An in-depth investigation of the actual structure and composition of the nanowires reveals a spontaneously formed Al gradient both along and across the nanowire, resulting in a complex core/shell structure with an Al-deficient core and an Al-rich shell with continuously varying Al content along the entire length of the (Al,Ga)N segment. This compositional change along the nanowire growth axis induces a polarization doping of the shell that results in a degenerate electron gas in the disk, thus screening the built-in electric fields. The high carrier density not only results in the unexpectedly high transition energies but also in radiative lifetimes depending only weakly on temperature, leading to a comparatively high internal quantum efficiency of the GaN quantum disks up to room temperature.

Interfacial reactions during the molecular beam epitaxy of GaN nanowires on Ti/Al2O3

We investigate the occurrence of interfacial reactions during the self-assembled formation of GaN nanowires on Ti/Al₂O₃(0001) substrates in plasma-assisted molecular beam epitaxy. The conditions typical for the synthesis of ensembles of long nanowires (>1 μm) are found to promote several chemical reactions. In particular, the high substrate temperature leads to the interdiffusion of Al and O at the Ti/Al₂O₃ interface resulting in the formation of Al _x Ti _y O_1-x-y and Ti _x O_1-x compounds. Furthermore, O is found to incorporate into the nanowires degrading their luminescence by heavy n-type doping. At the same time, impinging Ga and N species react with the substrate giving rise to the simultaneous formation of single-crystalline TiN and Ga _x Ti _y O_1-x-y compounds. The latter compounds tend to form hillocks at the substrate surface, on top of which nanowires elongate with large tilt angles with respect to the substrate normal. We develop here a specific process in order to mitigate the detrimental effects of these interfacial reactions, while maintaining the low areal density and absence of coalescence which is the strong asset of growing nanowires on Ti/Al₂O₃. We find that the combination of a thick Ti film with an intentional low temperature nitridation step preceding nanowire growth and a limited growth temperature results in ensembles of uncoalesced and well-oriented nanowires with luminescence properties comparable to those of standard GaN nanowires prepared on Si. All these properties, together with the inherent benefits of integrating semiconductors on metals, make the present materials combination a promising platform for the further development of group-III nitride nanowire-based devices.

[The analysis of the effect of psycho-intervention combined with diazepam on patients with sudden sensorineural hearing loss and anxiety]

Objective: To investigate the therapeutic effect of psychological intervention combined with diazepam on sudden hearing loss patients with anxiety. Method: 108 cases of sudden hearing loss patients with anxiety were randomly divided into two groups(n=54 in each group): The control group received routine treatment of sudden hearing loss, the study group was given psychological intervention combined with diazepam tablets(2.5 mg once, twice a day) based on the routine treatment. The hearing and HAMA and SAS scores were reviewed after 10 days of treatment. Result: After 10 days of treatment, the average hearing threshold of patients in the control group and the study group were respectively increased by （19.65±7.89）dB and （26.93±9.04）dB (t=4.54, P=0.006), the HAMA score of two groups were respectively decreased by 4.68 and 10.75（t=9.949, P=0.000）and the SAS score of two groups were respectively decreased by 15.93 and 23.39 (t=6.773, P=0.000), and the total efficiency of hearing of two groups were 61.11% and 77.78% (χ²=4.441, P=0.035),respectively. the differences were statistically significant. Conclusion: Psychological intervention combined with diazepam can relieve anxiety in patients with sudden hearing loss effectively, and play a positive role in the development and prognosis of patients with sudden sensorineural hearing loss.

Abstract P3-15-04: Signalling pathways targeted by the YangZheng Xiaoji extract and the therapeutic implications in human breast cancer

Background. Yangzheng Xiaoji is a formulation of Chinese medicine and has been used in the treatment of solid cancer as an adjuvant to chemotherapy by reducing the side effects to the patient. There has been evidence to show that the medicine has a direct biological role in cancer cells. In the present study, we sought to investigate the potential effects of the medicine on breast cancer cells and in particular aimed to identify the key targets and molecular pathways contributing to the anti-cancer effect of the medicine.

Methods. Human breast cancer cell lines (BT549, BT20, MDA MB-231, MCF-7 and ZR 75-1) with varying invasiveness and receptor status were used. The soluble extract of Yangzheng Xiaoji, namely DME25 was used in the study. The effects of DME25 on the growth, toxicity and cellular migration were assessed. Signalling kinase changes were screened using kinase antibody array based array technologies. Kinases were also validated using phosphorylation based protein blotting.

Results. Of the five breast cancer cell lines tested, Yangzheng Xiaoji extract DME25 showed little cytotoxicity over a broad range of concentrations. However, DME25 were able to markedly reduce the migration of the panel of breast cancer tested, without being toxic. Triple negative cells responded in a similar fashion with other cells. It was also noted that the adhesion of these cells were also inhibited by DME25. Using a protein kinase array, it was shown that a number of kinase complexes were inhibited by the medicine, notable ones including EGFR family kinases (reduced by 35%), Janus protein kinases (JAK) (by 57%), and Ras-related C3 botulinum toxin substrate (Rac1 or CDC42 GTPase) (by 49%) and Ribosomal protein S6 kinases (RSKs) (by 52%). Given the clinical significance of RSKs in human breast cancer, we further evaluated the role of RSK and RSK inhibitors in DME mediated cell functions and have demonstrated that both in triple negative breast cancer cells and receptor positive breast cancer cell lines, DME25 was able to synergistically enhance the effect of RSK2 inhibitor, SL1010-1, on the both the cellular migration and cell growth.

Conclusion. Yangzheng Xiaoji has a broad and direct effect on the migration of breast cancer, an effect unrelated to hormone receptor status and independent of cytotoxicity. The medicine appears to target kinase pathway, particularly for the RSK kinases, suggesting an important clinical implication in the treatment of breast cancer.

Citation Format: Jiang WG, Ye L, Owen S, Ruge F, Martin TA, Sanders AJ, Gao G, Wei C, Wu Y, Davies E. Signalling pathways targeted by the YangZheng Xiaoji extract and the therapeutic implications in human breast cancer [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 P3-15-04.

Are older drivers' driving patterns during an on-road driving task representative of their real-world driving patterns?

OBJECTIVE

The current study investigated whether older drivers' driving patterns during a customized on-road driving task were representative of their real-world driving patterns.

METHODS

Two hundred and eight participants (male: 68.80%; mean age = 81.52 years, SD = 3.37 years, range = 76.00-96.00 years) completed a customized on-road driving task that commenced from their home and was conducted in their own vehicle. Participants' real-world driving patterns for the preceding 4-month period were also collected via an in-car recording device (ICRD) that was installed in each participant's vehicle.

RESULTS

During the 4-month period prior to completing the on-road driving task, participants' median real-world driving trip distance was 2.66 km (interquartile range [IQR] = 1.14-5.79 km) and their median on-road driving task trip distance was 4.41 km (IQR = 2.83-6.35 km). Most participants' on-road driving task trip distances were classified as representative of their real-world driving trip distances (95.2%, n = 198).

CONCLUSIONS

These findings suggest that most older drivers were able to devise a driving route that was representative of their real-world driving trip distance. Future research will examine whether additional aspects of the on-road driving task (e.g., average speed, proportion of trips in different speed zones) are representative of participants' real-world driving patterns.