Two new indole-diterpenoids from the marine-derived fungus Penicillium sp. KFD28

Two new compounds named epipaxilline (1) and penerpene J (2) were isolated from the marine-derived fungus Penicillium sp. KFD28. Their structures including absolute configurations were determined on the basis of spectroscopic methods and ECD analysis. Compounds 1 and 2 showed inhibitory activities against PTP1B with IC₅₀ values of 31.5 and 9.5 μM, respectively, and compound 2 also showed inhibitory activities against TCPTP with IC₅₀ value of 14.7 μM.

Pancreatic Metastasis from Breast Cancer: A Clinicopathological Study of Four Cases by Fine Needle Aspiration

Introduction/Objective

Pancreatic metastases are rare, and the most common neoplasms are carcinomas from the kidney, lung, and breast.

Methods/Case Report

We present four cases of breast ductal carcinoma in patients with metastases to the pancreas diagnosed by endoscopic ultrasound guided fine needle aspiration (EUS-FNA). The four female patients ranged from 37 to 64 years in age. Three patients had breast cancer histories, ranging from 1 to 21 years. The patient without cancer history was found to have breast mass also. Two patients had triple negative breast ductal carcinoma. The breast cancer biomarkers on the other two patients showed ER+, PR-, Her2 3+, and ER-, PR-, Her2 3+, respectively. Two patients had histories of metastatic breast cancer involving bone, liver and brain. All patients presented with symptoms associated with pancreatic mass. By imaging, solitary pancreatic head masses were found in three patients, ranging from 2.4 to 3.7 cm. One patient had two pancreatic masses (head, 2.6 cm; body, 2.9 cm). EUS-FNAs targeting the pancreatic head masses were performed on the four patients. Cell blocks were available for all except one (due to limited cells), which had subsequent histology diagnosis.

Results (if a Case Study enter NA)

FNAs demonstrated loosely cohesive tumor cells with enlarged, hyperchromatic nuclei, occasional prominent nucleoli, and occasional intracytoplasmic vacuoles, morphologically and immunohistochemically (CK7 +, GCDFP-15 focally +, CA19.9 -, biomarkers similar to primary tumors) consistent with breast primary. Follow-up revealed three patients expired one month, 2.5 years, and 5 years post-diagnosis, respectively. One patient without prior cancer history has been stable for 7 years.

Conclusion

Our study demonstrates the clinicopathological features of four cases of breast ductal carcinoma metastasized to the pancreas. We emphasize the important role of EUS-FNA for diagnoses of pancreas metastases. The finding of two of four cases with triple negative biomarkers may raise the importance of close follow-up in these patients for pancreatic metastasis.

[Diagnosis and treatment of Chlamydia psittaci pneumonia: experiences of 8 cases]

Objective: In order to improve the understanding and clinical treatment of Chlamydia psittaci pneumonia, we analyzed the clinical manifestations, laboratory test results and imaging features of 8 patients. Methods: We collected the clinical data of 8 patients with Chlamydia psittaci pneumonia diagnosed by metagenomic next-generation-sequencing (mNGS) from November 2018 to February 2020, including clinical features, chest CT scan, pathological features and antibiotic use. Results: A total of one male and 7 females, aged from 45 to 85 years(median 62 years), were included in this study. All the patients had high fever, cough and most had expectoration (6/8). The leukocyte count and PCT level were mostly normal (7/8). However, we observed decreased lymphocyte count(5/8), elevated C-reactive protein in all patients, and increased ESR in most patients (7/8). The chest CT of all the patients showed large patchy consolidation, with one case having pleural effusion. The pathological manifestations were nonspecific, showing infiltration of inflammatory cells and exudation. Moxifloxacin and/or doxycycline were administered after diagnosis, and the course of treatment lasted from 14 to 21 days.Chest CT showed absorption of lesions following treatment Conclusions: Chlamydia psittaci pneumonia showed certain characteristics, including high fever with pulmonary patchy consolidation, and normal white blood cell count. Molecular diagnostic methods such as mNGS could lead to rapid diagnosis and treatment which can shorten the course of hospitalization and thus improve prognosis.

Alternative application of percutaneous cholecystostomy in patients with biliary obstruction

PURPOSE

Percutaneous cholecystostomy (PC) is an important modality for acute cholecystitis and has been applied for other clinical scenarios as well. In the present study, we aimed to investigate an alternative use of PC for obstructive jaundice.

METHODS

From January 2012 to December 2018, eligible subjects were selected from patients undergoing PC in our institute. The characteristics, spectrum of underlying disease, indication for PC performance, details of the procedure, and treatment effect were all investigated.

RESULTS

During the study period, 1364 patients underwent PC. Seventy patients fulfilled the defined inclusion criteria. While 47 patients were diagnosed with malignant biliary obstruction with or without cholangitis, 23 patients were diagnosed with nonmalignant biliary obstruction and acute cholangitis. There were 63 patients (90%) diagnosed with acute cholangitis. Pancreatic cancer (n = 24, 51%) and advanced malignancy (n = 28, 59%) were noted mostly in the group with malignant biliary obstruction. Treatment effects were proven by laboratory data, including the white blood cell count, C-reactive protein level, and hepatic function.

CONCLUSION

PC can temporize definitive therapies and serve as an alternative treatment for patients with nonmalignant conditions. For patients with advanced malignancy, PC can serve as a palliative procedure that has a high success rate and low complication rate and effectively relieves biliary obstruction.

Metabolism of Proteins and Amino Acids in Critical Illness: From Physiological Alterations to Relevant Clinical Practice

The clinical impact of nutrition therapy in critically ill patients has been known for years, and relevant guidelines regarding nutrition therapy have emphasized the importance of proteins. During critical illness, such as sepsis or the state following major surgery, major trauma, or major burn injury, patients suffer from a high degree of stress/inflammation, and during this time, metabolism deviates from homeostasis. The increased degradation of endogenous proteins in response to stress hormones is among the most important events in the acute phase of critical illness. Currently published evidence suggests that adequate protein supplementation might improve the clinical outcomes of critically ill patients. The role of sufficient protein supplementation may even surpass that of caloric supplementation. In this review, we focus on relevant physiological alterations in critical illness, the effects of critical illness on protein metabolism, nutrition therapy in clinical practice, and the function of specific amino acids.

[The prognostic value of myoglobin difference in sepsis related chronic critical illness]

Objective: To investigate the predictive value of myoglobin (Mb) for the prognosis of sepsis related chronic critical illness (CCI). Methods: Retrospective study was conducted on septic patients with the length of ICU stay equal or greater than 14 days, and sepsis-related organ failure assessment (SOFA) score equal or greater than 2 on the 14th day in ICU in the First Department of Critical Care Medicine at the First Affiliated Hospital of Sun Yat-sen University from January 2017 to March 2020. Patients' clinical and laboratory data were collected on the 1st and 14th day in ICU. The survival on day 28 in ICU was recorded. According to the myoglobin levels on day 1 and day 14, all subjects were divided into myoglobin elevation group and decline group. Kaplan-Meier survival curve was used to compare the cumulative survival rate at day 28. Cox regression analysis was used to analyze the independent risk factors of mortality. Receiver operating characteristic (ROC) curve was used to analyze the prognostic value of myoglobin. Results: A total of 131 patients with sepsis related CCI were recruited, including 58 patients in the elevation group and 73 in the decline group. The Mb level in elevation group on day 1 was significantly lower than that in decline group [172.40(59.99, 430.53) μg/L vs. 413.60(184.40, 1 328.50) μg/L, Z=3.749, P=0.000], and the Mb level on day 14 was the opposite change in two groups [483.65(230.38, 1 471.75)μg/L in elevation group vs. 132.20(76.86, 274.35)μg/L in decline group, Z=5.595, P=0.000]. Kaplan-Meier survival curve analysis showed that the 28-day cumulative survival rate of the elevation group was significantly lower than that of decline group (χ²=7.051, P=0.008). Cox ratio regression analysis suggested that elevated myoglobin was an independent risk factor for 28-day mortality in septic patients with CCI (OR=2.534, 95%CI 1.212-5.295, P=0.013). ROC curve analysis suggested that the sensitivity of myoglobin elevation in predicting mortality related to CCI within 28 days was 64.5%, and the specificity was 32.0% with area under the curve(AUC) 0.661(95%CI 0.550-0.773,P=0.007) and Jorden Index was 0.325. Conclusion: Elevated myoglobin, an independent risk factor for mortality within 28 days in ICU, can predict the prognosis of sepsis related chronic critical illness.

Impact of the highest amylase level in drain fluid on surgical outcomes and postoperative interventions in patients undergoing pancreaticoduodenectomy

OBJECTIVES

The clinical significance of the highest drain fluid amylase (DFA) level beyond pancreaticoduodenectomy (PD) postoperative day three (POD 3) remains unclear. This study investigated the impact of highest DFA level beyond POD 3 on postoperative pancreatic fistula (POPF) severity and outcomes of patients undergoing PD with POPF.

METHODS

Patient demographics of biochemical POPF and clinically relevant POPF (CR-POPF) were compared. Predictive factors were assessed using binary logistic regression. Receiver operating characteristic curve analysis was performed to determine the optimal cutoff value of highest DFA (beyond POD 3). We compared length of hospital stay, surgical mortality rates, and need for postoperative interventions by highest DFA level.

RESULTS

Patients with CR-POPF had an older age (p = 0.039), required intraoperative blood transfusion (p = 0.006), and had greater highest DFA levels (p = 0.001) than those with biochemical POPF. The optimal highest DFA cutoff was 2014.5 U/L. Multivariate analysis showed that percentage of patients with intraoperative blood transfusion (p = 0.011; odds ratio, 3.716) and a highest DFA > 2014.5 U/L beyond POD 3 (p = 0.001; odds ratio, 5.722) was predictive of CR-POPF.

CONCLUSION

Highest DFA > 2014.5 U/L beyond POD 3 is an independent predictor for CR-POPF. At a highest DFA >2014.5 U/L, 30-day surgical mortality rate, length of stay, and need for postoperative interventions did not differ.

Carcinogenesis of Male Oral Submucous Fibrosis Alters Salivary Microbiomes

Most oral squamous cell carcinoma (OSCC) tumors arise from oral premalignant lesions. Oral submucous fibrosis (OSF), usually occurring in male chewers of betel quid, is a premalignant stromal disease characterized by a high malignant transformation rate and high prevalence. Although a relationship between the inhabited microbiome and carcinogenesis has been proposed, no detailed information regarding the oral microbiome of patients with OSF exists; the changes of the salivary microbiome during cancer formation remain unclear. This study compared the salivary microbiomes of male patients with OSCC and a predisposing OSF background (OSCC-OSF group) and those with OSF only (OSF group). The results of high-throughput sequencing of the bacterial 16S rRNA gene indicated that OSF-related carcinogenesis and smoking status significantly contributed to phylogenetic composition variations in the salivary microbiome, leading to considerable reductions in species richness and phylogenetic diversity. The microbiome profile of OSF-related malignancy was associated with increased microbial stochastic fluctuation, which dominated the salivary microbiome assembly and caused species co-occurrence network collapse. Artificial intelligence selection algorithms consistently identified 5 key species in the OSCC-OSF group: Porphyromonas catoniae, Prevotella multisaccharivorax, Prevotella sp. HMT-300, Mitsuokella sp. HMT-131, and Treponema sp. HMT-927. Robust accuracy in predicting oral carcinogenesis was obtained with our exploratory and validation data sets. In functional analysis, the microbiome of the OSCC-OSF group had greater potential for S-adenosyl-l-methionine and norspermidine synthesis but lower potential for l-ornithine and pyrimidine deoxyribonucleotide synthesis and formaldehyde metabolism. These findings indicated that the salivary microbiome plays important roles in modulating microbial metabolites during oral carcinogenesis. In conclusion, our results provided new insights into salivary microbiome alterations during the malignant transformation of OSF.

Surgical options for submucosal tumors near the esophagogastric junction: does size or location matter?

Background

Submucosal tumors (SMTs) of different etiologies exist from esophagus to rectum. Esophagogastric junction (EGJ) is one of the known difficult locations for tumor resection. Although minimally invasive surgery (MIS) is a well-established approach for gastrointestinal surgery, there is no consensus that MIS for resection of SMTs around EGJ is superior to laparotomy. We tried to clarify the factors that determine the surgeons’ choices between these two approaches.

Methods

From January 2002 to June 2016, 909 patients with SMTs underwent resection in our department. Among them, 119 patients (13%) had SMTs around EGJ were enrolled by retrospective review. The clinicopathological features and tumor-related parameters were reviewed and analyzed.

Results

The cohort was stratified into three groups according to the extent of gastrectomy and surgical approaches. The three groups are as following: major gastrectomy (n = 13), minor gastrectomy by laparotomy (n = 51), and minor gastrectomy with MIS (n = 55). The average tumor size was significantly larger in the major gastrectomy group than in the two minor gastrectomy groups; however, there was no difference between the two minor gastrectomy groups (5.33 cm, 4.07 cm, and 3.69 cm, respectively). The minor gastrectomy with MIS required least hospital stay and operation duration also. We re-stratify the two minor gastrectomy groups (n = 106) according to the orientation of SMTs around the EGJ into 4 zones. Most of SMTs located on the greater curvature side of the EGJ were resected with MIS (82% versus 18%), whereas SMTs in the other zones were resected more often by laparotomy (59% versus 41%). There was no surgical mortality within the cohort, while minor gastrectomy with MIS yielded least number of leakages among the three groups.

Conclusions

For SMTs around the EGJ, larger tumors (diameter of more than 5 cm) are more likely to be resected with major gastrectomy. To resect SMTs around the EGJ in a wedge-like (minor gastrectomy) fashion, tumors located other than the greater curvature side were more often resected by laparotomy. However, MIS yielded acceptable safety and surgical outcomes compared to conventional laparotomy for SMTs around the EGJ of the same size.

[A comparison of the clinical diagnosis and outcome in preterm infants with bronchopulmonary dysplasia under two different diagnostic criteria]

Objective: To compare the clinical diagnosis and outcomes of preterm infants with bronchopulmonary dysplasia (BPD) under two different diagnostic criteria. Methods: A retrospective study was performed in 157 preterm infants who were admitted to Neonatal Intensive Care Unit of the Children's Hospital, Zhejiang University School of Medicine from January 2015 to December 2018. Enrolled infants, with gestational age <32 weeks and survived >14 days, met the 2001 National Institute of Child Health and Human Development(NICHD) definition of moderate and severe BPD or died between 14 days of postnatal age and 36 weeks owing to persistent parenchymal lung disease and respiratory failure. The severities of BPD were revaluated according to the 2018 revised definition of BPD proposed by NICHD. Characteristics and outcomes of these infants were compared with the two different diagnostic criteria with t-test, nonparametric test or Chi-square test. Results: In the 157 enrolled infants (100 males), severities of BPD were classified as moderate in 62, severe in 84 and unclassifiable in 11 according to the 2001 NICHD criteria, while grade Ⅰ in 51, Ⅱ in 29, Ⅲ in 66 and ⅢA in 11 infants respectively according to the 2018 NICHD criteria. Duration of oxygen therapy, positive pressure ventilation and endotracheal intubation in grade Ⅱinfants of 2018 criteria were much longer than that in moderate infants of 2001 criteria (80 (65, 95) vs. 65 (59, 77) d, 52 (38, 58) vs.30 (19, 48) d, 10 (2, 17) vs.4 (0, 12) d, Z=-2.995, -3.750, -2.073, all P<0.05). Mortality of moderate and severe infants in 2001 criteria was 10.3% (15/146), while mortality of BPD in 2018 criteria was 16.6% (26/157). Mortality of grade Ⅲ and ⅢA BPD in 2018 criteria was much higher than mortality of severe BPD in 2001 criteria (33.8% (26/77) vs. 17.9%(15/84), χ(2)=5.357, P<0.05). Conclusion: Definition and classification of BPD based on 2001 NICHD criteria may cause missed or unclassified cases, resulting in the underestimation of the morbidity and mortality of infants with severe BPD.

[Coexisting mutations in NPM1-mutated elderly adults with acute myeloid leukemia]

Objective: To explore the coexisting mutations in NPM1 mutated elderly patients with acute myeloid leukemia(AML). Methods: The clinical data of 152 elderly adults(aged≥60 years) and 49 young adults(aged 18-45 years) with AML between June 2013 and December 2018 in outpatient and hospitalized patients of Changzhou Second People's Hospital and Wuxi Second People's Hospital were retrospectively analyzed. A total of 51 gene mutations were detected using targeted next-generation sequencing (NGS) and sanger sequencing. The general clinical characteristics, the occurrence of coexistence gene mutations, the correlation between coexistence gene mutations and some clinical parameters, and the initial induction remission rate between elderly and young adult AML patients with NPM1 mutations were analyzed and compared. Results: NPM1 mutations were detected in 46 of 152 elderly AML patients. Thirty eight patients (82.6%) with NPM1 mutations carried other gene mutations at the same time, among whom 8 patients (17.4%) carried NPM1 mutations alone, while 14(30.4%) carried 2, 16 (34.8%) carried 3, and 8 (17.4%) carried ≥ 4 mutations. NPM1 mutations frequently co-occurred with FLT3-ITD15 cases (32.6%) , DNMT3A10 (21.7%) , TET26 (13.4%) and FLT3-TKD5 (10.9%) . Compared with young adults with NPM1 mutations, elderly patients had higher TP53, FLT3-TKD rates, lower incidence of DNMT3A, RAS mutation (all P<0.05) and lower coexistence rate of 4 gene mutations (P=0.002).The presence of ≥ 4 mutations was found to be significantly associated with higher white blood level than those in patients with single, double and 3 mutations coexisted in elderly adults AML patients(all P<0.05). With the increase of the amount of mutations, the complete remission(CR) rate decreased gradually after the initial induction. Patients who carried 3 or more mutations showed a lower CR rate than those with single gene mutations (all P<0.05) . Patients who carried>4 genes also showed a significantly lower CR rate than those with double gene mutations (P=0.031). Patients with FLT3-ITD mutations exhibited higher white blood level and lower CR rate than that in nonmutant type group (all P<0.05). The CR rate of patients with DNMT3A mutation was also significantly lower than that with nonmutant type (P=0.033). However, patients with FLT3-TKD mutations showed a higher platelet level than that with nonmutant type (P=0.019). There was no significant difference in CR rate and peripheral blood cell level between TET2 mutated and nonmutant type. Conclusion: NPM1 mutated elderly patients with AML commonly show additional mutations, and the amount and type of coexisting mutations have an influence on the clinical features and CR rate of elderly patients with AML.

Local Schottky contacts of embedded Ag nanoparticles in Al2O3/SiN x :H stacks on Si: a design to enhance field effect passivation of Si junctions

This paper describes an original design leading to the field effect passivation of Si n⁺-p junctions. Ordered Ag nanoparticle (Ag-NP) arrays with optimal size and coverage fabricated by means of nanosphere lithography and thermal evaporation, were embedded in ultrathin-Al₂O₃/SiN _x :H stacks on the top of implanted Si n⁺-p junctions, to achieve effective surface passivation. One way to characterize surface passivation is to use photocurrent, sensitive to recombination centers. We evidenced an improvement of photocurrent by a factor of 5 with the presence of Ag NPs. Finite-difference time-domain (FDTD) simulations combining with semi-quantitative calculations demonstrated that such gain was mainly due to the enhanced field effect passivation through the depleted region associated with the Ag-NPs/Si Schottky contacts.

[Value of sepsis single-disease manage system in predicting mortality in patients with sepsis]

Objective: To observe the effect of sepsis single-disease manage system on the improvement of sepsis treatment and the value in predicting mortality in patients with sepsis. Methods: A retrospective study was conducted. Patients with sepsis admitted to the Department of Surgical Intensive Care Unit of Sun Yat-Sen University First Affiliated Hospital from September 22, 2013 to May 5, 2015 were enrolled in this study. Sepsis single-disease manage system (Rui Xin clinical data manage system, China data, China) was used to monitor 25 clinical quality parameters, consisting of timeliness, normalization and outcome parameters. Based on whether these quality parameters could be completed or not, the clinical practice was evaluated by the system. The unachieved quality parameter was defined as suspicious parameters, and these suspicious parameters were used to predict mortality of patients with receiver operating characteristic curve (ROC). Results: A total of 1 220 patients with sepsis were enrolled, included 805 males and 415 females. The mean age was (59±17) years, and acute physiology and chronic health evaluation (APACHE Ⅱ) scores was 19±8. The area under ROC curve of total suspicious numbers for predicting 28-day mortality was 0.70; when the suspicious parameters number was more than 6, the sensitivity was 68.0% and the specificity was 61.0% for predicting 28-day mortality. In addition, the area under ROC curve of outcome suspicious number for predicting 28-day mortality was 0.89; when the suspicious outcome parameters numbers was more than 1, the sensitivity was 88.0% and the specificity was 78.0% for predicting 28-day mortality. Moreover, the area under ROC curve of total suspicious number for predicting 90-day mortality was 0.73; when the total suspicious parameters number was more than 7, the sensitivity was 60.0% and the specificity was 74.0% for predicting 90-day mortality. Finally, the area under ROC curve of outcome suspicious numbers for predicting 90-day mortality was 0.92; when suspicious outcome parameters numbers was more than 1, the sensitivity was 88.0% and the specificity was 81.0% for predicting 90-day mortality. Conclusion: The single center study suggests that this sepsis single-disease manage system could be used to monitor the completion of clinical practice for intensivist in managing sepsis, and the number of quality parameters failed to complete could be used to predict the mortality of the patients.

Transdermal Delivery of Luteinizing Hormone-releasing Hormone with Chitosan Microneedles: A Promising Tool for Androgen Deprivation Therapy

Long-term administration of luteinizing hormone-releasing hormone analogs (LHRHa) is the main type of androgen-deprivation therapy (ADT) for lethal prostate cancer. A fully insertable microneedle system, composed of embeddable chitosan microneedles and a dissolvable polyvinyl alcohol/polyvinyl pyrrolidone supporting array, was developed for sustained delivery of LHRHa to the skin. A porcine cadaver skin test showed that chitosan microneedles can be fully embedded within the skin and microneedle-created micropores reseal within 7 days. The measured LHRHa loading amount was 73.3±2.8 μg per microneedle patch. After applying goserelin-containing microneedles to mice, serum LH levels increased initially and then declined below baseline at day 7. In contrast, serum testosterone levels increased to reach a peak at day 14 and then declined to a castration level at day 21. Additionally, such a castration level was maintained for 2 weeks. Therefore, transdermal delivery of goserelin with embeddable chitosan microneedles can produce a castrated state in mice. Such a system is a promising, feasible means of delivering ADT.

[Clinical effectiveness of pleural abrasion in video-assisted thoracic surgery for bullae resection]

Objective: To evaluate the efficacy of pleural abrasion in treatment of spontaneous pneumothorax with video-assisted thoracic surgery (VATS) for bullae resection. Methods: The clinical data of 158 patients with initial spontaneous pneumothorax who underwent video-assisted thoracic wedge resections with or without pleural abrasion in Henan Provincial People's Hospital from June 2010 to June 2015 were retrospectively analyzed. The patients were assigned to two equal groups according to whether pleural abrasion was applied or not: experimental group (with pleural abrasion) and control group (without pleural abrasion); and there were 79 patients in each group.There were 62 males and 17 females aged 15-60 years (mean age 34 years) in pleural abrasion group. And there were 70 males and 9 females aged 18-60 years (mean age 38 years) in non-pleural abrasion group.After surgery, all patients were evaluated for postoperative pain, chest tube removal time, hospital stay and other complications.Independent samples t test was used to compare the data between groups. Results: Surgeries for 158 patients were performed successfully.No mortality occurred.There was no conversion to thoracotomy.Postoperative pain, operation time, intraoperative blood loss, chest tube removal time, pleural canals flowand average hospital stay in non-pleural abrasion group was significantly lower for 4.4, 19 minutes, 10 ml, 21 hours, 87 ml and 1.4 days respectively when compared with those in pleural abrasion group (t=32.478, 7.140, 11.093, 7.288, 10.246, 8.070, all P<0.05). There was no missing case with a follow-up of 30 months.No complications, such as pneumothorax, was observed. Conclusions: Postoperative pain, chest tube removal time and hospital stay in non-pleural abrasion group are all lower than those in pleural abrasion group.And there is no significant difference in the recurrence of pneumothorax between the two groups after VATS bullae resection.

[The surgical management of giant intracranial vestibular schwannoma via retrosigmoid approach: a retrospective review of 657 cases]

OBJECTIVE

To discuss the surgical technique and common complications from the microsurgical treatment of giant intracranial vestibular schwannoma via suboccipital retrosigmoid approach and to propose strategies for minimizing such complications.

METHODS

Surgical outcomes and complications were evaluated in a consecutive series of 657 unilateral giant vestibular schwannomas treated in Shanghai Huashan Hospital via suboccipital retrosigmoid approach from 1999 to 2014. According to the international classification of vestibular schwannoma, giant tumor means tumor's size over 4 cm in diameter. Clinical status and complications were assessed postoperatively within 14 days and at follow-ups (range, 6-191 months; mean, 59.6 months).

RESULTS

Follow-up data were available for 566 of the 657 patients (86.1%). The most frequent clinical symptoms were hearing loss in different levels (100%), deafness (36.4%), facial numbness (68.8%). Total tumor resection was achieved in 556 patients (84.6%), subtotal resection in 99 patients (15.1%), and partial resection in 2 patients (0.3%). The common postoperative complications included new deafness (49.6%), intracranial infection (7.6%), low cranial nerve defect (7.5%) and pneumonia (6.2%). The facial nerve was preserved anatomically in 589 cases (89.6%) after operation, and the functional valuation of facial nerve according to postoperative House-Brackmann showed 216 patients (32.9%) in grade Ⅰ-Ⅱ, 308 cases (46.9%) in grade Ⅲ, 133 patients (20.2%) in grade Ⅳ-Ⅵ. Long-term followed-up results showed 428 patients (75.6%) in grade Ⅰ-Ⅲ one year after surgical treatment.

CONCLUSIONS

Many of these complications are avoidable. Surgical experiences and the clinical anatomy of the approach, accompany with using intraoperative nerve monitoring, preoperatively study the individual imaging and clinical data and multidisciplinary cooperation are the key points to avoid the complications of giant intracranial vestibular schwannoma via suboccipital retrosigmoid approach.

High-order mode conversion based on adiabatical mode evolution for mode division multiplexing applications

Mode conversion based on adiabatical mode evolution in a two-core configuration is investigated. The configuration can convert all the launching modes to higher-order modes from one port and convert all the launching modes to lower-order modes from another port. Mode conversion between the two degenerated high-order modes is also demonstrated numerically. The mode conversion feature is only dependent on the relationship between the effective mode indices of the two cores in the configuration, which shows the characteristics of high flexibility and large fabrication tolerance.