Application of neuroendoscopic surgical techniques in the assessment and treatment of cerebral ventricular infection

Cerebral ventricular infection (CVI) is one of the most dangerous complications in neurosurgery because of its high mortality and disability rates. Few studies have examined the application of neuroendoscopic surgical techniques (NESTs) to assess and treat CVI. This multicenter, retrospective study was conducted using clinical data of 32 patients with CVI who were assessed and treated by NESTs in China. The patients included 20 men and 12 women with a mean age of 42.97 years. NESTs were used to obliterate intraventricular debris and pus, fenestrate or incise the intraventricular compartment and reconstruct cerebrospinal fluid circulation, and remove artificial material. Intraventricular irrigation with antibiotic saline was applied after neuroendoscopic surgery (NES). Secondary hydrocephalus was treated by endoscopic third ventriculostomy or a ventriculoperitoneal shunt. Neuroendoscopic findings of CVI were used to classify patients into Grade Ⅰ(n = 3), Grade Ⅱ(n = 13), Grade Ⅲ(n = 10), and Grade Ⅳ(n = 6) CVI. The three patients with grade ⅠCVI underwent one NES, the 23 patients with grade Ⅱ/Ⅲ CVI underwent two NESs, and patients with grade Ⅳ CVI underwent two (n = 3) or three (n = 3) NESs. The imaging features and grades of neuroendoscopy results were positively related to the number of neurosurgical endoscopic procedures. Two patients died of multiple organ failure and the other 30 patients fully recovered. Among the 26 patients with secondary hydrocephalus, 18 received ventriculoperitoneal shunt and 8 underwent endoscopic third ventriculostomy. There were no recurrences of CVI during the 6- to 76-month follow-up after NES. Application of NESTs is an innovative method to assess and treat CVI, and its neuroendoscopic classification provides an objective, comprehensive assessment of CVI. The study trial was approved by the Institutional Review Board of Beijing Shijitan Hospital, Capital Medical University, China.

The inner solar system cratering record and the evolution of impactor populations

We review previously published and newly obtained crater size-frequency distributions in the inner solar system. These data indicate that the Moon and the terrestrial planets have been bombarded by two populations of objects. Population 1,dominating at early times, had nearly the same size distribution as the present-day asteroid belt, and produced heavily cratered surfaces with a complex, multi-sloped crater size-frequency distribution. Population 2, dominating since about 3.8–3.7 Gyr,had the same size distribution as near-Earth objects(NEOs) and a much lower impact flux, and produced a crater size distribution characterized by a differential –3single-slope power law in the crater diameter range 0.02 km to 100 km. Taken together with the results from a large body of work on age-dating of lunar and meteorite samples and theoretical work in solar system dynamics, a plausible interpretation of these data is as follows. The NEO population is the source of Population 2 and it has been in near-steady state over the past ～ 3.7–3.8 Gyr; these objects are derived from the main asteroid belt by size-dependent non-gravitational effects that favor the ejection of smaller asteroids. However, Population 1 was composed of main belt asteroids ejected from their source region in a size-independent manner, possibly by means of gravitational resonance sweeping during orbit migration of giant planets;this caused the so-called Late Heavy Bombardment(LHB). The LHB began some time before ～3.9 Gyr, peaked and declined rapidly over the next ～ 100 to 300 Myr,and possibly more slowly from about 3.8–3.7 Gyr to ～2 Gyr. A third crater population(Population S) consisted of secondary impact craters that can dominate the cratering record at small diameters.

Development of a miniature silicon wafer fuel cell using L-ascorbic acid as fuel

In the current studies a miniature silicon wafer fuel cell(FC) using L-ascorbic acid as fuel was developed. The cell employs L-ascorbic acid and air as reactants and a thin polymer electrolyte as a separator. Inductively coupled plasma(ICP) silicon etching was employed to fabricate high aspect-ratio columns on the silicon substrate to increase the surface area. A thin platinum layer deposited directly on the silicon surface by the sputtering was used as the catalyst layer for L-ascorbic acid electro-oxidation. Cyclic voltammetry shows that the oxidation of L-ascorbic acid on the sputtered platinum layer is irreversible and that the onset potentials for the oxidation of L-ascorbic acid are from 0.27 V to 0.35 V versus an Ag/AgCl reference electrode. It is found that at the room temperature,with 1 mol/L L-ascorbic acid/PBS(phosphate buffered solution) solution pumped to the anode at 1 ml/min flow rate and air spontaneously diffusing to the cathode as the oxidant,the maximum output power density of the cell was 1.95 mW/cm2 at a current density of 10 mA/cm2.

Estimation of the elastic thickness over ancient Mare Moscoviense

The Moscoviense basin is an atypical lunar impact basin with concentric rings of positive and negative gravity anomalies. This basin can provide insights into the inhomogeneous thermal activities across the farside of the Moon. Based on an updated spherical harmonic thin elastic-shell loading model, we used localized admittance analyses to estimate the elastic thickness as well as other associated selenophysical parameters for the Moscoviense basin. The high precision gravity and topography data employed in our estimation were collected by the Gravity Recovery and Interior Laboratory and the Lunar Orbiter Laser Altimeter missions. Our results indicate that the crust-mantle interface is mainly compensated by the prefilling depth rather than the observed surface topography. The results constrained within two standard deviations yielded a small load ratio(~0.168), a best-fit crustal thickness of 36.2 km, and an optimized crustal density of 3159.5 kg m-3. Such large density approaches the density of olivine-rich mantle materials, implying that the excavation of the Mare Moscoviense occurred during a basin-forming impact. The inversed elastic thickness at Mare Moscoviense was around 18 km, lower than the previous results(~60 km) found over Mare basins on the lunar nearside. These results indicate that extreme thermal activity existed during the Moscoviense basin-forming period such as reheating mechanisms from a double-impact process and mare volcanism.

Metabolism alternation of schisandra chinensis in carbon tetrachloride-intoxicated rats and patients with advanced hepatocellular carcinoma

OBJECTIVE To study the pharmacokinetics change of schisandra chinensis under the pathological condition of liver dysfunction for safe and rational use of herbal medicines.METHODS The metabolism of four effective lignans from schisandra chinensis(SC),schisandrin,schisantherin A,deoxyshisandrin and γ-schisandrin was studied using microsomes from patients with advanced hepato.cellular carcinoma.In situ intestinal and hepatic perfusions were conducted to clarify the contributions from impairments of gut and liver on the pharmacokinetics of the four schisandra lignans in CCl4-intoxi.cated rats.The metabolism in rat and human liver microsomes and transport in Caco-2 monolayer cell model were studied to reveal the key factors for the in vivo disposition of the four lignans.RESULTS When SC alcoholic extract was orally administrated to CCl4-intoxicated rat for a short term(4 d),the pharmacokinetics of four active SC lignans was significantly changed while its hepatoprotective effect was not obviously observed.The plasma concentrations of the four schisandra lignans were dramatical.ly elevated compared with the control.The Cmax,AUC and MRT were all increased or prolonged signif.icantly while parameter CLz/F was obviously reduced in rat pretreated with CCl4.In hepatic perfusion study and liver microsomes incubation,it was found that the hepatic metabolism of the four lignans was markedly decreased mainly due to the activity reduction of multiple CYP450 isoenzymes involved the metabolism,which,eventually,might lead to the alternation of their pharmacokinetic profiles in CCl4-intoxicated rats or patients with advanced hepatocellular carcinoma.CONCLUSION The pharmacoki.netic studies of SC components in pathological situation of liver dysfunction are expected to provide useful data for rational and safe application of SC preparations in clinic or further pharmacological and toxicological research.

Efficacy and safety of acupuncture for polycystic ovary syndrome:An overview of systematic reviews

Background:Polycystic ovary syndrome(PCOS)is the primary cause of anovulatory infertility,bringing serious harm to women’s physical and mental health.Acupuncture may be an effective treatment for PCOS.However,systematic reviews(SRs)on the efficacy and safety of acupuncture for PCOS have reported inconsistent results,and the quality of these studies has not been adequately assessed.Objective:To summarize and evaluate the current evidence on the efficacy and safety of acupuncture for PCOS,as well as to assess the quality and risks of bias of the available SRs.Search strategy:Nine electronic databases(Cochrane Library,MEDLINE,Embase,PsycINFO,CINAHL,Chinese National Knowledge Infrastructure,Wanfang Data,Chongqing VIP Chinese Science and Technology Periodical Database,and China Biology Medicine disc)were searched from their establishment to July 27,2022.Based on the principle of combining subject words with text words,the search strategy was constructed around search terms for“acupuncture,”“polycystic ovary syndrome,”and“systematic review.”Inclusion criteria:SRs of randomized controlled trials that explored the efficacy and(or)safety of acupuncture for treating patients with PCOS were included.Data extraction and analysis:Two authors independently extracted study data according to a predesigned form.Tools for evaluating the methodological quality,risk of bias,reporting quality,and confidence in study outcomes,including A Measurement Tool to Assess Systematic Reviews 2(AMSTAR 2),Risk of Bias in Systematic Reviews(ROBIS),Preferred Reporting Items for Systematic Reviews and Metaanalyses for Acupuncture(PRISMA-A),and the Grading of Recommendations Assessment,Development and Evaluation(GRADE),were used to score the included SRs.Results:A total of 885 studies were retrieved,and 11 eligible SRs were finally included in this review.The methodological quality of 2 SRs(18.18%)was low,while the other 9 SRs(81.82%)were scored as extremely low.Four SRs(36.36%)were considered to be of low risk of bias.As for reporting quality,the reporting completeness of 9 SRs(81.82%)was more than 70%.Concerning the confidence in study results,2study results were considered to have a high quality of evidence(3.13%),14(21.88%)a“moderate”quality,28(43.75%)a“low”quality,and 20(31.24%)considered a“very low”quality.Descriptive analyses suggested that combining acupuncture with other medicines can effectively improve the clinical pregnancy rate(CPR)and ovulation rate,and reduce luteinizing hormone/follicle-stimulating hormone ratio,homeostasis model assessment of insulin resistance,and body mass index(BMI).When compared with medicine alone,acupuncture alone also can improve CPR.Further,when compared with no intervention,acupuncture had a better effect in promoting the recovery of menstrual cycle and reducing BMI.Acupuncture was reported to cause no adverse events or some adverse events without serious harm.Conclusion:The efficacy and safety of acupuncture for PCOS remains uncertain due to the limitations and inconsistencies of current evidence.More high-quality studies are needed to support the use of acupuncture in PCOS.

Efficacy analysis of flexible neuroendoscopy combined with dry-field techniques in the treatment of chronic subdural hematoma

Chronic subdural hematoma (CSDH) is a common and frequently occurring disease in neurosurgery, whose incidence accounts for around 10% of all intracranial hematomas. There have been many theories about the mechanism of CSDH, including acute subdural hematoma, slow hemorrhage after bridge vein injury, and traumatic subdural effusion evolution With improvements in medical imaging technology and related basic research, the perception of CSDH as an inflammatory vascular proliferative disease has gradually reached consensus In addition to head trauma, brain atrophy leading to expanded subdural space is the premise and primary reason for the occurrence of CSDH in the older adult population.

Image Encryption Algorithm Based on Compressive Sensing and Fractional DCT via Polynomial Interpolation

Based on compressive sensing and fractional discrete cosine transform(DCT)via polynomial interpolation(PI-FrDCT),an image encryption algorithm is proposed,in which the compression and encryption of an image are accomplished simultaneously.It can keep information secret more effectively with low data transmission.Three-dimensional piecewise and nonlinear chaotic maps are employed to obtain a generating sequence and the exclusive OR(XOR)matrix,which greatly enlarge the key space of the encryption system.Unlike many other fractional transforms,the output of PI-FrDCT is real,which facilitates the storage,transmission and display of the encrypted image.Due to the introduction of a plain-image-dependent disturbance factor,the initial values and system parameters of the encryption scheme are determined by cipher keys and plain-image.Thus,the proposed encryption scheme is very sensitive to the plain-image,which makes the encryption system more secure.Experimental results demonstrate the validity and the reliability of the proposed encryption algorithm.