Urinary microRNAs miR-15b and miR-30a as novel noninvasive biomarkers for gentamicin-induced acute kidney injury

MicroRNAs serve as potential biomarkers in various pathological models, and are stable and detectable in biofluids. We investigated the urinary microRNA expression profile in a gentamicin-induced acute kidney injury canine model using RNA sequencing. A total of 234 differentially expressed microRNAs were screened after 12 consecutive days of gentamicin administration (P < 0.05). Six candidate microRNAs (miR-15b, -15b-3p, -16, -30a, -30a-3p, and -30c-2-3p) were selected according to a set criterion, and validated by real-time quantitative PCR. The diagnostic values of these six candidate microRNAs were better than the traditional serum biomarkers (all P < 0.05). Further, using receiver operating characteristic curve analysis, we found that miR-15b and -15b-3p were superior to urinary kidney injury molecule-1 (both P < 0.05). Moreover, miR-15b and -30a levels in the urine samples significantly correlated with their respective levels in the kidney tissue samples (r=0.512 and 0.505, respectively, both P < 0.05). Our data concluded that miR-15b and -30a may be promising biomarkers for renal toxicity.

Management of cN0 papillary thyroid microcarcinoma patients according to risk-scoring model for central lymph node metastasis and predictors of recurrence

BACKGROUND

The role of routine prophylactic central neck dissection (pCND) in clinically lymph node-negative (cN0) papillary thyroid microcarcinoma (PTMC) patients remains controversial. This retrospective study aimed to identify the clinical and pathologic factors of central lymph node metastasis (CLNM) and recurrence in PTMC patients.

METHODS

A total of 371 cN0 PTMC patients from two hospitals were retrospectively analyzed. All patients underwent thyroidectomy plus pCND between January 2010 and January 2018. Clinicopathological features were collected, univariate and multivariate analyses were performed to determine the risk factors of CLNM. A scoring model was constructed on the basis of the results of independent risk factors of CLNM. The Cox proportional hazards model was used to analyze the risk factors of recurrence.

RESULTS

CLNM occurred in 123 (33.2%) patients. Multivariate analysis showed male, tumor size > 0.75 cm, multifocality, extrathyroidal extension (ETE) and tumor in the middle/lower pole were independent risk predictors of CLNM (P < 0.05). A seven-point risk-scoring model was established to predict the stratified CLNM in cN0 PTMC patients. Multivariate Cox regression model showed ETE, vascular invasion and CLNM were independent risk predictors of recurrence (P < 0.05).

CONCLUSION

Our study suggested that routine pCND should be performed for cN0 PTMC patients with score ≥ 3 according to the risk-scoring model. Moreover, patients with risk factors of recurrence should consider more complete treatment and more frequent follow-up.

[Analysis of the hard and soft tissue following immediate and early implant placement in the anterior area of maxilla]

Objective: To compare the difference of soft and hard tissue changes between immediate implant and early implant placement in maxillary anterior region, so as to provide the basis for the selection of implant timing and surgical method for patients in clinical maxillary anterior dental esthetic zone. Methods: From January 2016 to January 2019, 89 patients [48 males and 41 females, aged (38.0±13.3) years] with dentition defect and single tooth implant restoration in the Department of Oral Implantology, Dalian Stomatological Hospital were retrospectively collected. The patients were divided into three groups according to different implant timing and operation methods: immediate implant flapless group (26 cases), immediate implant flap group (30 cases) and early implant group (33 cases, early implant 4-8 weeks after tooth extraction). The operation time, intraoperative and postoperative complications were compared among the three groups. Cone-beam CT was taken before operation, immediately after operation and 6 months after operation. The bone plate thickness immediately after implantation, bone plate thickness at 6 months after operation and absorption amount of bone plate thickness at labial side (immediately after operation minus 6 months after operation) were measured, and the absorption rate of labial bone plate was calculated. Three dimensional quantitative analysis was performed on the lip bone increment, residual bone volume (6 months after operation minus preoperative), and bone volume absorption rate of the three groups immediately after operation by using GuideMia, PlastyCAD and Geomagic engineering software. The pink and white esthetic indexes of the three groups were evaluated at 9 months and 15 months after implant placement. The implant stability quotient (ISQ) value was measured at 6 months after implantation, and the patients' satisfaction with the whole treatment process was investigated at 6 months after implantation. Results: The operation time of immediate implant flapless group was the shortest, the median (lower quartile, upper quartile) was 36.5 (33.3, 38.5) min. At 9 months after operation, PES was relatively high [8.5 (8.0, 9.0)], and the final patient satisfaction was 8.0 (7.3, 8.8), and the difference was statistically significant compared with the other two groups (P<0.05). There was no significant difference in the incidence of intraoperative and postoperative complications among the groups (P>0.05). At 6 months after operation, the thickness of labial bone plate in early group was 3.09 (3.00, 3.25) mm, which was greater than that in the immediate non flap group [1.90 (1.72, 2.33) mm] and that in the immediate implant flap group [2.39 (2.05, 3.06) mm], and the difference was statistically significant (P<0.05). The absorption of labial bone thickness in immediate implant flapless group [0.61 (0.35, 0.98) mm] was significantly lower than that in the immediate implant flap group [1.13 (0.97, 1.53) mm] and that in the early implant group [1.23 (1.07, 1.37) mm] (P<0.05). After 6 months, the residual bone volume of immediate flapless group was 38.7 (31.2, 54.6) mm³ and was significantly different from that in early implant group [109.1 (85.6, 263.1) mm³] (P<0.05), and there was no significant difference in the residual bone volume between immediate implant flapless group and immediate implant flap group (P>0.05). Conclusions: Immediate implant can reduce the treatment time with equal esthetic outcome of implant supported restoration of anterior teeth, and patients prefer it more. The bone volume of lip side was not significantly increased after immediate flap operation, and the bone absorption was less after immediate flap operation. Early implant placement can better maintain the three-dimensional bone mass, and the three groups can obtain good clinical results in the short term, but the long-term effect needs further follow-up study.

[Risk factors of permanent stoma in rectal cancer patients undergoing transabdominal anterior resection with temporary stoma]

Objective: To investigate the risk factors of turning temporary stoma into permanent stoma in rectal cancer patients undergoing transabdominal anterior resection with temporary stoma. Methods: A case-control study was carried out. Data of rectal cancer patients who underwent transabdominal anterior resection with temporary stoma and completed follow-up in Department of General Surgery of Xiangya Hospital of Central South University from June 2008 to June 2018 were collected and analyzed. In this study, temporary stoma included defunctioning stoma (ostomy was made during operation) and salvage stoma (ostomy was made within one month after operation due to anastomotic leakage or severe complications). Cases of multiple intestinal tumors were excluded. A total of 308 rectal cancer patients were enrolled in the study, including 198 males and 110 females with a median age of 56 (48-65) years. Ninety-four patients received intraperitoneal chemotherapy during operation. Among 308 patients, upper rectal cancer was observed in 64 cases, middle rectal cancer in 89 cases and low rectal cancer in 155 cases. Twenty patients underwent transverse colostomy and 288 underwent ileostomy. Phone call following-up was conducted from August to September 2019 to investigate whether stoma was reversed, causes of reversal failure, and tumor relapsed or not in detail. Permanent stoma was defined as that the stoma was still not reversed by the latest follow-up. The univariate analysis was performed with chi-square test or Fisher's exact test, and variables with P value < 0.10 were included in the non-conditional logistic regression model for multivariate analysis. Results: The median follow-up time was 54.3 (32.4-73.8) months. During follow-up, 8 cases had local recurrence and 37 cases had distant metastasis. Among the 308 patients with temporary ostomy, 247 (80.2%) patients had stomas reversed and the median interval time was 4.5 (3.5-6.1) months. The median interval time in 65 patients with salvage stoma was significantly longer that in 182 patients with defunctioning stoma [5.5 (4.3-7.5) vs. 4.2 (3.4-5.5) months; Z=-4.387, P<0.001]. The temporary ostomy was confirmed to become permanent stoma in 61 patients (19.8%), including 45 cases of defunctioning stoma and 16 cases of salvage stoma. Univariate analysis showed that preoperative anemia, intraperitoneal chemotherapy during operation, middle rectal cancer, transverse colostomy, pathological stage, postoperative local recurrence and distant metastasis were associated with permanent stoma (all P<0.10). Multivariate analysis revealed that the intraperitoneal chemotherapy during operation (OR=1.961, 95% CI: 1.029-3.738, P=0.041), middle rectal cancer (OR=2.401, 95% CI: 1.195-4.826, P=0.014), transverse colostomy (OR=3.433, 95% CI: 1.234-9.553, P=0.018), and distant metastasis (OR=8.282, 95% CI:3.820-17.954, P<0.001) were independent risk factors of permanent stoma. Conclusions: There is high risk of turning temporary stoma into permanent stoma among rectal cancer patients undergoing transabdominal anterior resection who receive intraperitoneal chemotherapy during operation, present as the middle rectal cancer, undergo transverse colostomy or develop distant metastasis. Surgeons need to evaluate and balance the risks and benefits thoroughly, and then inform the patients in order to avoid potential conflicts.

The ELFIN Mission

The Electron Loss and Fields Investigation with a Spatio-Temporal Ambiguity-Resolving option (ELFIN-STAR, or heretoforth simply: ELFIN) mission comprises two identical 3-Unit (3U) CubeSats on a polar (∼93^∘ inclination), nearly circular, low-Earth (∼450 km altitude) orbit. Launched on September 15, 2018, ELFIN is expected to have a >2.5 year lifetime. Its primary science objective is to resolve the mechanism of storm-time relativistic electron precipitation, for which electromagnetic ion cyclotron (EMIC) waves are a prime candidate. From its ionospheric vantage point, ELFIN uses its unique pitch-angle-resolving capability to determine whether measured relativistic electron pitch-angle and energy spectra within the loss cone bear the characteristic signatures of scattering by EMIC waves or whether such scattering may be due to other processes. Pairing identical ELFIN satellites with slowly-variable along-track separation allows disambiguation of spatial and temporal evolution of the precipitation over minutes-to-tens-of-minutes timescales, faster than the orbit period of a single low-altitude satellite (T_orbit ∼ 90 min). Each satellite carries an energetic particle detector for electrons (EPDE) that measures 50 keV to 5 MeV electrons with Δ E/E < 40% and a fluxgate magnetometer (FGM) on a ∼72 cm boom that measures magnetic field waves (e.g., EMIC waves) in the range from DC to 5 Hz Nyquist (nominally) with <0.3 nT/sqrt(Hz) noise at 1 Hz. The spinning satellites (T_spin ∼ 3 s) are equipped with magnetorquers (air coils) that permit spin-up or -down and reorientation maneuvers. Using those, the spin axis is placed normal to the orbit plane (nominally), allowing full pitch-angle resolution twice per spin. An energetic particle detector for ions (EPDI) measures 250 keV - 5 MeV ions, addressing secondary science. Funded initially by CalSpace and the University Nanosat Program, ELFIN was selected for flight with joint support from NSF and NASA between 2014 and 2018 and launched by the ELaNa XVIII program on a Delta II rocket (with IceSatII as the primary). Mission operations are currently funded by NASA. Working under experienced UCLA mentors, with advice from The Aerospace Corporation and NASA personnel, more than 250 undergraduates have matured the ELFIN implementation strategy; developed the instruments, satellite, and ground systems and operate the two satellites. ELFIN's already high potential for cutting-edge science return is compounded by concurrent equatorial Heliophysics missions (THEMIS, Arase, Van Allen Probes, MMS) and ground stations. ELFIN's integrated data analysis approach, rapid dissemination strategies via the SPace Environment Data Analysis System (SPEDAS), and data coordination with the Heliophysics/Geospace System Observatory (H/GSO) optimize science yield, enabling the widest community benefits. Several storm-time events have already been captured and are presented herein to demonstrate ELFIN's data analysis methods and potential. These form the basis of on-going studies to resolve the primary mission science objective. Broad energy precipitation events, precipitation bands, and microbursts, clearly seen both at dawn and dusk, extend from tens of keV to >1 MeV. This broad energy range of precipitation indicates that multiple waves are providing scattering concurrently. Many observed events show significant backscattered fluxes, which in the past were hard to resolve by equatorial spacecraft or non-pitch-angle-resolving ionospheric missions. These observations suggest that the ionosphere plays a significant role in modifying magnetospheric electron fluxes and wave-particle interactions. Routine data captures starting in February 2020 and lasting for at least another year, approximately the remainder of the mission lifetime, are expected to provide a very rich dataset to address questions even beyond the primary mission science objective.

Acid-Catalyzed Rearrangements of 3-Aryloxirane-2-Carboxamides: Novel DFT Mechanistic Insights

Efficient synthesis of 3-arylquinolin-2(1H)-ones and N-(2-carboxyaryl)-oxalamides from protic acid-catalyzed rearrangements of 3-aryloxirane-2-carboxamides was achieved recently but not well understood. In contrast to the classical Meinwald rearrangement, extensive DFT calculations reveal that the proximal aryl and amide groups have strong synergetic effects to control the amide-aided and aryl-directed oxirane-opening and further rearrangement sequences. The ortho-nitro substituent of the proximal aryl is directly involved in a nucleophilic oxirane ring-opening, the amide C=O is an important proton shuttle for facile H-shifts, while the N-aryl may act as a potential ring-closing site via Friedel-Crafts alkylation. The mechanistic insights are useful for rational design of novel synthesis by changing the aryl and amide functional groups proximal to the oxirane ring.

Total tumor diameter: the neglected value in papillary thyroid microcarcinoma

BACKGROUND

Tumor multifocality is not uncommon in papillary thyroid carcinoma (PTC), especially in micro-PTC. However, assessing the size of the largest tumor may underestimate effect of additional foci. We aimed to investigate the effect of total tumor diameter (TTD) on clinicopathological features of micro-PTC.

METHODS

Data from 442 patients who underwent thyroidectomy with cervical lymph node dissection for PTC were retrospectively analyzed. Patients were classified into subgroups according to multifocality and TTD. The relationships of clinicopathological features among these groups were analyzed.

RESULTS

Multifocality was observed in 119 patients (26.9%). TTD > 1 cm and presence of extrathyroidal extension (ETE) were significantly higher in multifocal tumors compared to unifocal tumor (P < 0.001, P = 0.016, respectively). When comparing multifocal micro-PTC with TTD > 1 cm to those with unifocal micro-PTC or multifocal micro-PTC with TTD ≤ 1 cm, the proportions of cases with ETE, central lymph node metastasis (CLNM), and lateral lymph node metastasis (LLNM) were significantly higher (all P < 0.05). There was no significant difference in terms of these parameters between multifocal micro-PTC with TTD > 1 cm and macro-PTC or multifocal macro-PTC. The risk of CLNM was 2.056 (P = 0.044) times higher in multifocal micro-PTC with TTD > 1 cm than in unifocal micro-PTC.

CONCLUSION

For multifocal micro-PTC, TTD can better assess the aggressiveness of the tumor. Multifocal micro-PTC with TTD > 1 cm was more aggressive than unifocal micro-PTC or multifocal micro-PTC with TTD ≤ 1 cm.

[Analysis of misdiagnosis causes of suprasellar arachnoid cysts]

Objective: To investigate the causes of misdiagnosis of suprasellar arachnoid cysts, analyze its characteristics and put forward the diagnostic basis and differential points. Methods: The clinical data fo 97 cases of suprasellar arachnoid cysts diagnosed and treated in the neurosurgery department of Beijing Tiantan Hospital and Hebei General Hospital from March 2015 to March 2019 were analyzed retrospectively. All patients underwent CT and MRI scans with obstructive hydrocephalus. 13 cases were misdiagnosed, including 7 males and 6 females. First visit age 1-31 years old, with an average age of 6.3 years. There were 10 patients younger than 6 years old. The remaining 15-year-old patients, 31-year-old patients and 26-year-old patients each have one case. 11 cases were misdiagnosed as obstructive hydrocephalus, 2 cases as cystic craniopharyngioma. Results: 13 cases were misdiagnosed and mistreated, 11 cases were treated with intraventricular and abdominal shunt, 9 cases were treated with neuroendoscopy and recovered well. One cases of intracranial hematomas underwent craniotomy again, the hematomas were removed again and the bone slise were decompressed. One case had fissured stable after shunt. There were no operative deaths and no complications in this group. After endoscopic reoperation, CT and/or MRI scans showed that the ventricle narrowed in varying degrees, some of them returned to normal size and the flow of cerebrospinal fluid (cerebrospinal fluid) was unobstruct at the end of magnetic resonance cerebrospinal fluid angiography (MRI) fistula after endoscopic reoperation. Conclusions: The incidence of suprasellar arachnoid cysts is low, it is rare in clinic and it is easy to misdiagnose and mistreate. At present, it is recognized that the best treatment methods are partial resection of endoscope cyst wall, cyst ventricle fistula and third ventricle floor fisthla.

Development of ATLID Retrieval Algorithms

ATLID (“ATmospheric LIDar”) is the lidar to be flown on the multi-instrument Earth Clouds and Radiation Explorer (EarthCARE or ECARE) joint ESA/JAXA mission now scheduled for launch in 2022. ATID is a 3 channel linearly polarized High-Spectral Resolution (HSRL) system operating at 355nm. Cloud and aerosol optical properties are key ECARE products. This paper will provide an overview of the ATLID L2a (i.e. single instrument) retrieval algorithms being developed and implemented in order to derive cloud and aerosol optical properties.

[Interpretation of clinical practice guideline for anorectal day surgery 2019 edition]

As the rapid development of minimally invasive techniques, anesthesia, and enhanced recovery after surgery (ERAS), anorectal day surgery receiving more and more attention by improving efficiency of medical care while reducing cost and hospitalized infection. However, day surgery also faces the challenge of completing the whole process from patient admission to discharge within 24 hours. Therefore, establishing a reasonable and detailed day surgery process is the cornerstone to guarantee safe medical practice and patients satisfaction. National Clinical Research Center for Geriatric Disorders (Xiangya), together with China Ambulatory Surgery Alliance formulates the clinical practice guideline for anorectal day surgery 2019 edition. Here we make some interpretations of the guidelines on the detailed process of anorectal day surgery, including indication, preoperative examination, preoperative risk evaluation, health education, assessment of day surgery anesthesia and before leaving postanesthesia care unit (PACU), postoperative management, assessment of discharge and follow-up, for the convenience of various medical centers.

Catalytic Difunctionalization of Unactivated Alkenes with Unreactive Hexamethyldisilane through Regeneration of Silylium Ions

A metal-free, intermolecular syn-addition of hexamethyldisilane across simple alkenes is reported. The catalytic cycle is initiated and propagated by the transfer of a methyl group from the disilane to a silylium-ion-like intermediate, corresponding to the (re)generation of the silylium-ion catalyst. The key feature of the reaction sequence is the cleavage of the Si-Si bond in a 1,3-silyl shift from silicon to carbon. A central intermediate of the catalysis was structurally characterized by X-ray diffraction, and the computed reaction mechanism is fully consistent with the experimental findings.

Anomalous Thermoelectric Effects of ZrTe_{5} in and beyond the Quantum Limit

Thermoelectric effects are more sensitive and promising probes to topological properties of emergent materials, but much less addressed compared to other physical properties. We study the thermoelectric effects of ZrTe_{5} in a magnetic field. The presence of the nontrivial electrons leads to the anomalous Nernst effect and quasilinear field dependence of thermopower below the quantum limit. In the strong-field quantum limit, both the thermopower and Nernst signal exhibit exotic peaks. At higher magnetic fields, the Nernst signal has a sign reversal at a critical field where the thermopower approaches zero. We propose that these anomalous behaviors can be attributed to the gap closing of the zeroth Landau bands in topological materials with the band inversion. Our understanding to the anomalous thermoelectric properties in ZrTe_{5} opens a new avenue for exploring Dirac physics in topological materials.

Fractional Deletion of Compound Kushen Injection Indicates Cytokine Signaling Pathways are Critical for its Perturbation of the Cell Cycle

We used computational and experimental biology approaches to identify candidate mechanisms of action of aTraditional Chinese Medicine, Compound Kushen Injection (CKI), in a breast cancer cell line (MDA-MB-231). Because CKI is a complex mixture of plant secondary metabolites, we used a high-performance liquid chromatography (HPLC) fractionation and reconstitution approach to define chemical fractions required for CKI to induce apoptosis. The initial fractionation separated major from minor compounds, and it showed that major compounds accounted for little of the activity of CKI. Furthermore, removal of no single major compound altered the effect of CKI on cell viability and apoptosis. However, simultaneous removal of two major compounds identified oxymatrine and oxysophocarpine as critical with respect to CKI activity. Transcriptome analysis was used to correlate compound removal with gene expression and phenotype data. Many compounds in CKI are required to trigger apoptosis but significant modulation of its activity is conferred by a small number of compounds. In conclusion, CKI may be typical of many plant based extracts that contain many compounds in that no single compound is responsible for all of the bioactivity of the mixture and that many compounds interact in a complex fashion to influence a network containing many targets.

Acylation Reactions of Dibenzo-7-phosphanorbornadiene: DFT Mechanistic Insights

Extensive DFT calculations provide deep mechanistic insights into the acylation reactions of tert-butyl dibenzo-7-phosphanobornadiene with PhCOX (X=Cl, Br, I, OTf) in CH2Cl2 solution. Such reactions are initialized by the nucleophilic P⋅⋅⋅C attack to the carbonyl group to form the acylphosphonium intermediate A+ together with X- anion, followed either by nucleophilic X-⋅⋅⋅P attack (X=Cl, Br, and I) toward A+ to eliminate anthracene or by slow rearrangement or decomposition of A+ (X=OTf). In contrast to the first case (X=Cl) that is rate-limited by the initial P⋅⋅⋅C attack, other reactions are rate-limited by the second X-⋅⋅⋅P attack for X=Br and I and even thermodynamically prevented for X=OTf, leading to isolable phosphonium salts. The rearrangement of phosphonium A+ is initiated by a P-C bond cleavage, followed either by sequential proton-shifts to form anthracenyl acylphosphonium or by deprotonation with additional base Et3N to form neutral anthracenyl acylphosphine. Our DFT results strongly support the separated acylphosphonium A+ as the key reaction intermediate that may be useful for the transfer of acylphosphenium in general.

Suspended low-loss germanium waveguides for the longwave infrared

Germanium is a material of high interest for mid-infrared (MIR) integrated photonics due to its complementary metal-oxide-semiconductor (CMOS) compatibility and its wide transparency window covering the 2-15 μm spectral region exceeding the 4 and 8 μm limit of the silicon-on-insulator platform and Si material, respectively. In this Letter, we report suspended germanium waveguides operating at a wavelength of 7.67 μm with a propagation loss of 2.6±0.3  dB/cm. To the best of our knowledge, this is the first demonstration of low-loss suspended germanium waveguides at such a long wavelength. Suspension of the waveguide is achieved by defining holes alongside the core providing access to the buried oxide layer and the underlying Si layer so that they can be wet etched using hydrofluoric acid and tetramethylammonium hydroxide, respectively. Our MIR waveguides create a new path toward long wavelength sensing in the fingerprint region.

Suspended silicon waveguides for long-wave infrared wavelengths

In this Letter, we report suspended silicon waveguides operating at a wavelength of 7.67 μm with a propagation loss of 3.1±0.3  dB/cm. To our knowledge, this is the first demonstration of low-loss silicon waveguides at such a long wavelength, with loss comparable to other platforms that use more exotic materials. The suspended Si waveguide core is supported by a sub-wavelength grating that provides lateral optical confinement while also allowing access to the buried oxide layer so that it can be wet etched using hydrofluoric acid. We also demonstrate low-loss waveguide bends and s-bends.