Single-crystal growth, structure and thermal transport properties of the metallic antiferromagnet Zintl-phase β-EuIn2As2

Zintl-phase materials have attracted significant research interest owing to the interplay of magnetism and strong spin-orbit coupling, providing a prominent material platform for axion electrodynamics. Here, we report the single-crystal growth, structure, magnetic and electrical/thermal transport properties of the antiferromagnet layer Zintl-phase compound β-EuIn2As2. Importantly, the new layered structure of β-EuIn2As2, in rhombohedral (R3̄m) symmetry, contains triangular layers of Eu2+ ions. The in-plane resistivity ρ(H, T) measurements reveal metal behavior with an antiferromagnetic (AFM) transition (TN ∼ 23.5 K), which is consistent with the heat capacity Cp(H, T) and magnetic susceptibility χ(H, T) measurements. Negative MR was observed in the temperature range from 2 K to 20 K with a maximum MR ratio of 0.06. Unique 4f7J = S = 7/2 Eu2+ spins were supposed magnetically order along the c-axis. The Seebeck coefficient shows a maximum thermopower |Smax| of about 40 μV K-1. The kink around 23 K in the Seebeck coefficient originates from the effect of the antiferromagnetic phase on the electron band structure, while the pronounced thermal conductivity peak at around 10 K is attributed to the phonon-phonon Umklapp scattering. The results suggest that the Eu2+ spin arrangement plays an important role in the magnetic, electrical, and thermal transport properties in β-EuIn2As2, which might be helpful for future potential technical applications.

[The application of 3D bioprinting in ophthalmology]

On the basis of 3D printing technology, 3D bioprinting has emerged with great development potential and good prospects in the field of medicine and tissue engineering. With this technique, different types of cells and biomaterials can be precisely incorporated into 3D anatomical structures, achieving tissue substitutes with superior structures or functions. In recent years, great progress has been made in the application of 3D bioprinting in ophthalmology. This article reviews not only the differences between 3D printing and 3D bioprinting, but also the development, types, characteristics, application, and prospects of 3D bioprinting in the production of eye tissue engineering materials.

Combining Multiple Plant Attributes to Reveal Differences in Community Structure in Two Distant Deserts in Central Asia

International interest is growing in biodiversity conservation and sustainable use in drylands. Desert ecosystems across arid Central Asia are severely affected by global change. Understanding the changes in a plant community is an essential prerequisite to revealing the community assembly mechanism, vegetation conservation, and management. The knowledge of large-scale spatial variation in plant community structure in different Central Asian deserts is still limited. In this study, we selected the Taukum (TD, Kazakhstan) and the Gurbantunggut (GD, China) deserts as the research area, with similar latitudes despite being nearly 1000 km apart. Thirteen and 15 sampling plots were set up and thoroughly investigated. The differences in community structure depending on multiple plant attributes (individual level: plant height, canopy diameter, and plant volume, and community level: plant density, total cover, and total volume) were systematically studied. TD had a better overall environmental status than GD. A total of 113 species were found, with 68 and 74 in TD and GD, respectively. The number of species and plant attributes was unequally distributed across different families and functional groups between deserts. The values of several plant attributes, such as ephemerals, annuals, dicotyledons, and shrubs with assimilative branches in GD, were significantly lower than those in TD. The Motyka indices of six plant attributes (26.18-38.61%) were higher between the two deserts than the species similarity index (20.4%), indicating a more robust convergence for plant functional attributes. The community structures in the two deserts represented by different plant attribute matrices demonstrated irregular differentiation patterns in ordination diagrams. The most variance in community structure was attributed to soil and climatic factors, while geographic factors had the smallest proportion. Consequently, the community structures of the two distant deserts were both different and similar to an extent. This resulted from the long-term impacts of heterogeneous environments within the same region. Our knowledge is further deepened by understanding the variation in community structure in different deserts on a large spatial scale. This therefore provides valuable insights into conserving regional biodiversity in Central Asia.

Effects of N and P additions on twig traits of wild apple (Malus sieversii) saplings

BACKGROUND

Wild apple (Malus sieversii) is under second-class national protection in China and one of the lineal ancestors of cultivated apples worldwide. In recent decades, the natural habitation area of wild apple trees has been seriously declining, resulting in a lack of saplings and difficulty in population regeneration. Artificial near-natural breeding is crucial for protecting and restoring wild apple populations, and adding nitrogen (N) and phosphorous (P) is one of the important measures to improve the growth performance of saplings. In this study, field experiments using N (CK, N1, N2, and N3: 0, 10, 20, and 40 g m^- 2 yr^- 1, respectively), P (CK, P1, P2, and P3: 0, 2, 4, and 8 g m^- 2 yr^- 1, respectively), N20Px (CK, N2P1, N2P2, and N2P3: N20P2, N20P4 and N20P8 g m^- 2 yr^- 1, respectively), and NxP4 (CK, N1P2, N2P2, and N3P2: N10P4, N20P4, and N40P4 g m^- 2 yr^- 1, respectively) treatments (totaling 12 levels, including one CK) were conducted in four consecutive years. The twig traits (including four current-year stem, 10 leaf, and three ratio traits) and comprehensive growth performance of wild apple saplings were analyzed under different nutrient treatments.

RESULTS

N addition had a significantly positive effect on stem length, basal diameter, leaf area, and leaf dry mass, whereas P addition had a significantly positive effect on stem length and basal diameter only. The combination of N and P (NxP4 and N20Px) treatments evidently promoted stem growth at moderate concentrations; however, the N20Px treatment showed a markedly negative effect at low concentrations and a positive effect at moderate and high concentrations. The ratio traits (leaf intensity, leaf area ratio, and leaf to stem mass ratio) decreased with the increase in nutrient concentration under each treatment. In the plant trait network, basal diameter, stem mass, and twig mass were tightly connected to other traits after nutrient treatments, indicating that stem traits play an important role in twig growth. The membership function revealed that the greatest comprehensive growth performance of saplings was achieved after N addition alone, followed by that under the NxP4 treatment (except for N40P4).

CONCLUSIONS

Consequently, artificial nutrient treatments for four years significantly but differentially altered the growth status of wild apple saplings, and the use of appropriate N fertilizer promoted sapling growth. These results can provide scientific basis for the conservation and management of wild apple populations.

[A preliminary study on the prevention of hemorrhage after laparoscopic pancreaticoduodenectomy by wrapping gastroduodenal artery stump in the left external liver lobe and the left caudate lobe]

Objective: To investigate the safety and efficacy of embedding the stump of gastroduodenal artery between the left lateral lobe of the liver and the left caudate lobe to prevent bleeding after laparoscopic pancreaticoduodenectomy. Methods: The clinical data of 41 patients who underwent laparoscopic pancreaticoduodenectomy at the second Hospital of Hebei Medical University from October 2021 to April 2022 were analyzed retrospectively.There were 27 males and 14 females, aged (63.0±9.2)years (range: 48 to 78 years), and the body mass index was (24.1±3.2)kg/m² (range: 15.4 to 31.6 kg/m²). After routine laparoscopic pancreaticoduodenectomy, the stump of gastroduodenal artery was embedded between the left lateral lobe and the left caudate lobe of the liver, and the hepatic parenchyma of the left lateral lobe and the left caudate lobe were sutured with absorbable sutures.The occurrence and recovery of postoperative complications (pancreatic fistula, biliary fistula, postoperative abdominal bleeding, abdominal infection, liver abscess) were observed. Results: All the operations of 41 patients were completed successfully.The operation time was (277.5±52.0) minutes (range: 192 to 360 minutes). The entrapment time of gastroduodenal artery stump was (3.1±0.6) minutes (range: 2.3 to 4.2 minutes), and the intraoperative blood loss (M(IQR)) was 300 (200) ml (range: 50 to 800 ml).The results of ultrasound examination of hepatic artery on the first day after operation showed that the blood flows of hepatic artery were unobstructed.Postoperative pancreatic fistula occurred in 3 cases, including grade B pancreatic fistula in 2 cases (1 case with abdominal infection) and biochemical leakage in 1 case. Three patients with pancreatic fistula were discharged successfully after continuous abdominal drainage. There was no biliary fistula, abdominal bleeding, abdominal infection, liver abscess or postoperative liver dysfunction. Conclusion: The encasement of the gastroduodenal artery stump by the left outer and left caudate lobes of the liver may be an effective way to prevent bleeding from the rupture of the gastroduodenal artery stump after laparoscopic pancreatoduodenectomy, which is easy and safe to perform.

Differences and allometric relationships among assimilative branch traits of four shrubs in Central Asia

Shrubs play a major role in maintaining ecosystem stability in the arid deserts of Central Asia. During the long-term adaptation to extreme arid environments, shrubs have developed special assimilative branches that replace leaves for photosynthesis. In this study, four dominant shrubs with assimilative branches, namely Haloxylon ammodendron, Haloxylon persicum, Calligonum mongolicum, and Ephedra przewalskii, were selected as the research objects, and the dry mass, total length, node number, and basal diameter of their assimilative branches and the average length of the first three nodes were carefully measured, and the allometric relationships among five traits of four species were systematically compared. The results indicated that: (1) Four desert shrubs have different assimilative branches traits. Compared with H. persicum and H. ammodendron, C. mongolicum and E. przewalskii have longer internodes and fewer nodes. The dry mass of H. ammodendron and the basal diameter of H. persicum were the smallest; (2) Significant allometric scaling relationships were found between dry mass, total length, basal diameter, and each trait of assimilative branches, all of which were significantly less than 1; (3) The scaling exponents of the allometric relationship between four traits and the dry mass of assimilative branches of H. persicum were greater or significantly greater than those of H. ammodendron. The scaling exponents of the relationships between the basal diameter, dry mass, and total length of E. przewalskii were higher than those of the other three shrubs. Therefore, although different species have adapted to drought and high temperatures by convergence, there was great variability in morphological characteristics of assimilative branches, as well as in the scaling exponents of relationships among traits. The results of this study will provide valuable insights into the ecological functions of assimilative branches and survival strategies of these shrubs to cope with aridity and drought in desert environments.

Stover return and nitrogen application affect soil organic carbon and nitrogen in a double-season maize field

Cultivation techniques have an important influence on grain yield of maize. This experiment investigated the effect of stover return (SR) and different nitrogen (N) application rate on soil organic carbon (SOC) composition, soil nutrient and maize yield. Different nitrogen application rate 100 (N100), 150 (N150), 200 (N200), 250 (N250) or 300 (N300) kg ha^-1 applied to the maize field with stover return and without stover return traditional planting (TP) method. Nitrogen application rate and stover return affected the SOC, labile organic carbon (LOC), microbial biomass (MBC), NO₃ ^- -N, NH₄ ⁺ -N and maize yield. Soil N, soil carbon content and maize yield of SR were all higher than TP. The SOC content of SR and TP were 9.67 and 9.19 g kg^-1 , respectively. Nitrogen application was significantly and positively correlated with soil MBC, LOC, SOC, NO₃ ^- -N, NH₄ ⁺ -N and yield. The maximum values of SOC composition, soil nutrients and maize yield were reached at SR with 250 kg ha^-1 . Stover return with application of N 250 kg ha^-1 significantly increased the growth attribute and maize yield in subtropical region compared with traditional planting.

Thermal Dynamics of Charge Density Wave Pinning in ZrTe_{3}

Impurity pinning has long been discussed to have a profound effect on the dynamics of an incommensurate charge density wave (CDW), which would otherwise slide through the lattice without resistance. Here, we visualize the impurity pinning evolution of the CDW in ZrTe_{3} using the variable temperature scanning tunneling microscopy. At low temperatures, we observe a quasi-1D incommensurate CDW modulation moderately correlated to the impurity positions, indicating a weak impurity pinning. As we raise the sample temperature, the CDW modulation gets progressively weakened and distorted, while the correlation with the impurities becomes stronger. Above the CDW transition temperature, short-range modulations persist with the phase almost all pinned by impurities. The evolution from weak to strong impurity pinning through the CDW transition can be understood as a result of losing phase rigidity.

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.

[Stem hydraulic architecture of Malus sieversii in degraded wild fruit forest in Ili valley, China]

To reveal mechanisms underlying the dieback of Malus sieversii in degraded wild fruit forest in Ili valley of China, we compared the differences in stem hydraulic architecture, water transport effectiveness and safety, as well as their influencing factors among three growth classes of dead branches ratios, including Class Ⅰ (<20%), Class Ⅱ (40%-60%) and Class Ⅲ (>80%), respectively. With the increases in degradation degree of Xinjiang wild fruit forest, sapwood-specific hydraulic conductivity and leaf-specific hydraulic conductivity decreased, without significant differences among the three growth classes. Branch embolism at dusk and hydraulic safety significantly increased. The xylem water potential at 50% loss of hydraulic conductivity was -1.87, -1.35 and -0.53 MPa for Class Ⅰ, Ⅱ and Ⅲ, respectively. Predawn and midday leaf water potential and the hydraulic safety margin exhibited an order of Ⅰ>Ⅱ>Ⅲ. Xylem anatomical cha-racteristics and branch and leaf traits related to hydraulics were significantly different among the three growth classes. Results from correlation analysis revealed a weak tradeoff between xylem-specific hydraulic efficiency and xylem safety of M. sieversii. Stem hydraulic architecture of M. sieversii altered with the decline of Xinjiang wild apple forest. With increasing degrees of degradation, the severity of xylem embolisms aggravated, resistance to cavitation embolisms reduced, and the risk of water imbalance increased.

[Clinical characteristics of recurrent appendicitis]

Objective: To analyze clinical characteristics of recurrent appendicitis. Methods: A retrospective cohort study was carried out. Clinical data of patients who underwent appendectomy due to acute appendicitis confirmed by pathology in the Affiliated Hospital of Qingdao University from January 2011 to December 2015 were analyzed retrospectively. Exclusion criteria: (1) age of less than 18 years;(2) chronic appendicitis; (3) periappendiceal abscess; (4) appendiceal mucocele or mucinous neoplasms; (5) appendiceal neuroendocrine tumors or cancers; (6) appendicitis during pregnancy; (7) concurrent AIDS, hematological disease, autoimmune disease, inflammatory bowel disease or advanced cancer; (8) other simultaneous surgery. A total of 373 patients were enrolled the study. These patients were divided into the recurrent group (133 cases) and the first episode group (240 cases) according to the previous history of antibiotic therapy for acute appendicitis. The prevalence of recurrent appendicitis was calculated, and the clinical characteristics were analyzed, including gender, age, comorbidities and preoperative CT images. Results: Of 373 patients, 209 were male and 164 were female, with a median age of 42 (18 to 88) years. Median recurrent time of the recurrent group was 4 (1 to 60) months. Compared to the first episode group, the recurrent group had higher proportion of age <50 years [71.4% (95/133) vs. 57.5% (138/240), χ(2)=7.081, P=0.008], higher proportion of concurrent diabetes [13.5% (18/133) vs. 5.4% (13/240), χ(2)=7.399, P=0.007], shorter onset time [(41.7±13.6) hours vs. (59.4±56.2) hours, t=-3.286, P=0.001], lower proportion of abdominal tension and rebound pain [57.9% (77/133) vs. 66.7% (160/240), χ(2)=5.065, P=0.024], lower score of modified Alvarado score [(5.6±1.9) point vs. (6.1±1.9) point, t=-2.417, P=0.016], lower WBC count [(10.5±4.6) ×10(9)/L vs. (11.5±4.5)×10(9)/L, t=-1.190, P=0.047], higher percentage of lymphocyte [(19.4±14.7)% vs. (16.1±13.3)%, t=2.069, P=0.039]. In the recurrent group, ratio of length of removed appendix ≥7 cm was higher as compared with the first episode group [44.4% (59/133) vs. 32.9% (79/240), χ(2)=4.808, P=0.028], while the ratio of complicated appendicitis was significantly lower [8.3% (11/133) vs. 22.9% (55/240), χ(2)=10.823, P=0.001]. CT images were available in 129 patients, intraluminal appendicoliths was found in 19 of 50 patients (38%) in the recurrent group, while in 16 of 79 patients (20.3%) in the first episode group, and there was statistically significant difference between the two groups (χ(2)=4.880, P=0.027). Conclusions: Clinical characteristics of recurrent acute appendicitis include age less than 50 years, concurrent diabetes, short onset time, less abdominal tension or rebound pain, low modified Alvarado score, low WBC count, high percentage of lymphocyte, appendix length longer than 7 cm, non-complicated appendicitis and intraluminal appendicoliths.

[Retrospective investigation of spontaneous bloody tears: a report of 27 cases]

Objective: To summarize clinical experience on the clinical feature, etiology and treatment of patients with spontaneous bloody tears as the initial symptom. Methods: Retrospective series of case studies. The clinical data and follow-up data of 27 cases of bloody tears as the first symptom in Lacrimal Center of Ophthalmology, the Third Medical Center of Chinese PLA General Hospital from June 2015 to December 2018 were reviewed. The clinical feature, specific cause, diagnosis, treatment and prognosis of these cases were evaluated. Results: A total of 27 cases were collected in this study. The patients were 10 males (37.0%) and 17 females (63.0%), including 21 adults (≥ 18 years old, 77.8%) and 6 minors (<18 years old, 22.2%). There were 22 monocular cases (81.5%) and 5 binocular cases (18.5%). Five cases (18.5%) were bleeding from the eye and other parts of the body, and 22 cases (81.5%) were bleeding only from the eye. There were 19 cases (70.4%) with hematic epiphora and secretions from the punctum, 3 cases (11.1%) with blood-stained tears, and 7 cases (25.9%) with blood-like tears. With regard to etiology, 6 cases (22.2%) were combined with systemic lesions, one of which was granulomatosis with polyangiitis and five of which (<18 years old) were idiopathic bloody tears. Twenty-one cases (77.8%) were local lesions, including 18 cases only involving the lacrimal system, 2 cases only involving the ocular surface, and 1 case involving both the lacrimal system and the ocular surface. Among the 21 cases with local lesions, 5 cases were induced by foreign body, 6 cases were induced by simple inflammation, and 10 cases were induced by tumor including 1 case with conjunctival benign tumor and 9 cases with tumor of the lacrimal system (5 with malignant tumor and 4 with benign tumor). Patients with idiopathic bloody tears received psychological and medical treatment, and interictal discharge was lengthened. One case of granulomatosis with polyangiitis was treated by trans-nasal endoscopic dacryocystorhinostomy. With the recurrence of granulomatosis and polyangiitis, bloody tears recurred after surgery. One patient with conjunctival hemangioma was untreated. Lesions in the lacrimal duct system were removed and dacryocystorhinostomy was performed. In this study, 2 patients (1 with small cell neuroendocrine carcinoma and 1 with adenoid cystic adenocarcinoma) died and the other had a good prognosis. Conclusions: Among the cases of bloody tears, adults and local lesions are more common. Most of the lesions are located in the lacrimal system and are tumors. The main treatment is to remove the lesions, and if necessary, to expand the resection and reconstruct the lacrimal duct. Idiopathic bloody tears occur in minors, who are gave psychotherapy and necessary medical treatment. (Chin J Ophthalmol, 2020, 56: 53-58).

LncRNAGAS5 sponges miRNA-221 to promote neurons apoptosis by up-regulated PUMA under hypoxia condition

Objectives: Long noncoding RNAs (lncRNAs) play substantial roles in cerebral ischemia. Growth arrest-specific 5 (GAS5) was reported to be involved in stroke. In the present study, we aimed to investigate the roles of GAS5 in cerebral condition and unveil the underlying mechanism.Method: Transient focal ischemia was induced by intraluminal occlusion of the right Middle cerebral artery occlusion (MCAO) and 2,3,5-triphenyltetrazolium chloride (TTC) staining was used to evaluate the volume of cerebral infarction. RT-qPCR was applied to evaluate the level of GAS5 and miR-221. Fluorescence activated Cell Sorting (FACS) and Terminal deoxynucleotidyl transferased (TUNEL)  were used for detection of apoptosis. Western blotting was applied for protein level. Luciferase assay was applied to reveal the underlying relationship between GAS5 and miR-221 or p53-upregulated modulator of apoptosis (PUMA) and miR-221.Results: The results indicated that GAS5 was up-regulated in MCAO rats and in vitro hypoxia cell model while miR-221 expression was decreased in vitro hypoxia cell model. GAS5 promoted cells apoptosis, while miR-221 inhibited cell apoptosis through regulation of PUMA and downstream JNK/H2AX signaling. Moreover, GAS5 and miR-221 have direct interaction and PUMA was the target of miR-221, indicating that GAS5 regulated PUMA through sponging miR-221.Conclusions: the present study revealed that GAS5 aggravated cell apoptosis in hypoxia condition via miR-221/PUMA axis, which may provide potential targets for the treatment of stroke.

Pulmonary infection complicated with gastroesophageal reflux in children: Influential factors and clinical features

AIM

To explore the influencing factors and clinical features for pulmonary infection complicated with gastroesophageal reflux (GER) in children.

METHODS

A total of 139 children with pulmonary infection admitted to Changshan County People's Hospital from March 2015 to August 2017 were selected as an experimental group and 98 children who were examined at our hospital during the same period were selected as a reference group. All children were monitored for 24-h esophageal pH. The relationship between pulmonary infection and GER was analyzed, and Logistic regression method was used to analyze the influencing factors on them. The clinical features of children with pulmonary infection complicated with GER were summarized.

RESULTS

The number of reflux episodes, mean time to reflux, longest reflux time, acid elimination time, acid exposure time, Boix-Ochoa score, and GER positive rate in the experimental group were significantly higher than those in the reference group (P < 0.05 for all). Univariate analysis showed that the factors influencing pulmonary infection complicated with GER were age, severity of illness, chronic pharyngitis, and sedative drug use (P < 0.05 for all), but gender had no effect (P > 0.05). Logistic regression analysis showed that age, severity of illness, chronic pharyngitis, and sedation drug use in children affected the occurrence of pulmonary infection complicated with GER (P < 0.05 for all). Of the 56 children with GER who developed pulmonary infection, 29 developed coughing, 21 developed galactorrhea, 11 developed vomiting, 8 developed crying and antifeedant, 6 developed choking, 5 developed wheezing, and 2 developed wheezing respiration. Among them, cough and galactorrhea were found in 13 cases, cough and vomit in 7 cases, cough and crying antifeedant in 6 cases, and cough and choking symptoms in 4 cases. There were 29 (51.79%) children with underlying diseases: 11 cases of laryngeal softening, 5 cases of milk allergy and congenital heart disease each, 3 cases of exercise retardation, 2 cases of funnel chest and esophageal hiatus each, and 1 case of malnutrition.

CONCLUSION

The incidence of GER in children with pulmonary infection is high, and age, severity of pulmonary infection, chronic pharyngitis, and sedative drug use are risk factors affecting their occurrence. There are many basic diseases in these children. GER should be considered in children with pulmonary infection who have clinical symptoms associated with cough, galactorrhea, vomiting, crying and antifeedant, choking, and wheezing.

Accuracy and efficiency of computer-aided anatomical analysis using 3D visualization software based on semi-automated and automated segmentations

OBJECTIVE

We investigated and compared the functionality of two 3D visualization software provided by a CT vendor and a third-party vendor, respectively. Using surgical anatomical measurement as baseline, we evaluated the accuracy of 3D visualization and verified their utility in computer-aided anatomical analysis.

METHODS

The study cohort consisted of 50 adult cadavers fixed with the classical formaldehyde method. The computer-aided anatomical analysis was based on CT images (in DICOM format) acquired by helical scan with contrast enhancement, using a CT vendor provided 3D visualization workstation (Syngo) and a third-party 3D visualization software (Mimics) that was installed on a PC. Automated and semi-automated segmentations were utilized in the 3D visualization workstation and software, respectively. The functionality and efficiency of automated and semi-automated segmentation methods were compared. Using surgical anatomical measurement as a baseline, the accuracy of 3D visualization based on automated and semi-automated segmentations was quantitatively compared.

RESULTS

In semi-automated segmentation, the Mimics 3D visualization software outperformed the Syngo 3D visualization workstation. No significant difference was observed in anatomical data measurement by the Syngo 3D visualization workstation and the Mimics 3D visualization software (P>0.05).

CONCLUSIONS

Both the Syngo 3D visualization workstation provided by a CT vendor and the Mimics 3D visualization software by a third-party vendor possessed the needed functionality, efficiency and accuracy for computer-aided anatomical analysis.

Morphometric measurement of the cervical spine for minimally invasive pedicle screw fixation using reverse engineering and three-dimensional reconstruction

BACKGROUND

Percutaneous cervical pedicle screw fixation has been proven to be an effective method of cervical screw instrumentation, which has the advantages of less invasiveness and low blood loss. Emerging evidence has indicated that the cervical spinous process plays an important role in percutaneous spine surgery. However, there is a limited amount of information on the fundamental research of pedicle and its associated imaging parameter measurement. The purpose of this study was to measure the anatomic data of the pedicle screw channel (PSC) using reverse engineering and three-dimensional reconstruction, and also to discuss the three-dimensional relationship between the cervical spinous process and the pedicle screw channel.

METHODS

Twenty adult subjects (10 males, 10 females, age range 19-46 years) were studied using the method of three-dimensional CT reconstruction and reverse engineering. The centrum was divided into 10 equal parts from front to back. The bisectors were defined as borderline depths of the centrum, from front to back, 100%, 90%, 80%, 70%, 60%, 50%, 40%, 30%, 20%, 10%, 0% of borderline depths were presented. Then, a 3D coordinate system was constructed to measure all the data, including the radius of the inscribed circle, the length of the PSC, the insertion angle, the distances from entry point to cervical spinous process and skin depth. All the indexes were measured from 70% to 90% borderline depth.

RESULTS

The radius of the inscribed circles from C₃ to C₇ at 90% borderline depth were 2.94 ± 0.55 mm, 3.04 ± 0.40 mm, 3.15 ± 0.36 mm, 3.28 ± 0.47 mm, 3.89 ± 0.54 mm, respectively. The lengths of the PSC were between 25 and 32 mm. The insertion angles for 70% to 90% borderline depth were 28.33°, 34.28°, 37.92°, respectively. The relationship between the PSC and spinous process was measured as the distance from the entry point to the end of the spinous process, which were, respectively, 26.91 mm, 28.18 mm, 30.03 mm, 35.67 mm, 41.99 mm from C₃ to C₇ .The distance from the skin to the entry point of C_3-7 increased gradually.

CONCLUSIONS

The measurements of this study could provide detailed information for percutaneous cervical screw fixation. The data of the relationship between the cervical spinous process and the pedicle screw channel present valuable technical information for the design, optimization and clinical application of the aiming device for percutaneous cervical pedicle screw fixation. Copyright © 2016 John Wiley & Sons, Ltd.

Score model for predicting acute-on-chronic liver failure risk in chronic hepatitis B

AIM: To establish a clinical scoring model to predict risk of acute-on-chronic liver failure (ACLF) in chronic hepatitis B (CHB) patients.

METHODS: This was a retrospective study of 1457 patients hospitalized for CHB between October 2008 and October 2013 at the Beijing Ditan Hospital, Capital Medical University, China. The patients were divided into two groups: severe acute exacerbation (SAE) group (n = 382) and non-SAE group (n = 1075). The SAE group was classified as the high-risk group based on the higher incidence of ACLF in this group than in the non-SAE group (13.6% vs 0.4%). Two-thirds of SAE patients were randomly assigned to risk-model derivation and the other one-third to model validation. Univariate risk factors associated with the outcome were entered into a multivariate logistic regression model for screening independent risk factors. Each variable was assigned an integer value based on the regression coefficients, and the final score was the sum of these values in the derivation set. Model discrimination and calibration were assessed using area under the receiver operating characteristic curve and the Hosmer-Lemeshow test.

RESULTS: The risk prediction scoring model included the following four factors: age ≥ 40 years, total bilirubin ≥ 171 μmol/L, prothrombin activity 40%-60%, and hepatitis B virus DNA > 10⁷ copies/mL. The sum risk score ranged from 0 to 7; 0-3 identified patients with lower risk of ACLF, whereas 4-7 identified patients with higher risk. The Kaplan-Meier analysis showed the cumulative risk for ACLF and ACLF-related death in the two risk groups (0-3 and 4-7 scores) of the primary cohort over 56 d, and log-rank test revealed a significant difference (2.0% vs 33.8% and 0.8% vs 9.4%, respectively; both P < 0.0001). In the derivation and validation data sets, the model had good discrimination (C index = 0.857, 95% confidence interval: 0.800-0.913 and C index = 0.889, 95% confidence interval: 0.820-0.957, respectively) and calibration demonstrated by the Hosmer-Lemeshow test (χ² = 4.516, P = 0.808 and χ² = 1.959, P = 0.923, respectively).

CONCLUSION: Using the scoring model, clinicians can easily identify patients (total score ≥ 4) at high risk of ACLF and ACLF-related death early during SAE.

Xijiao Dihuang Decoction () and Rehmannia glutinosa Libosch. protect mice against lipopolysaccharide and tumor necrosis factor alpha-induced acute liver failure

OBJECTIVE

To investigate the hepatoprotective effect of Xijiao Dihuang Decoction (, XJDHD) on lipopolysaccharide (LPS)- and tumor necrosis factor alpha (TNF-α)-induced acute liver failure (ALF) as well as the underlying mechanism of action, and to clarify the key herbs and components of XJDHD.

METHODS

LPS/D-galactosamine (D-GalN) or TNF-α/D-GalN were intraperitoneally injected into C57BL/6J mice to induce ALF. Simultaneously, XJDHD or its individual herbs and components were orally administered. Survival rates, transaminase levels in serum, and hepatic histology were examined to evaluate the effects of XJDHD. The terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay and real-time polymerase chain reaction were additionally performed to expound the mechanism underlying the anti-apoptotic activity of XJDHD.

RESULTS

Oral administration of XJDHD protected mice from lethal liver failure induced by LPS and TNF-α, with notable amelioration of liver injury in histology and a significant decrease in transaminase levels in serum. XJDHD significantly inhibited apoptosis of hepatocytes and enhanced expression of the antiapoptosis genes, c-Flip, Iap1, Gadd45b and A20. In addition, Rehmannia glutinosa Libosch. was identified as the key herb of XJDHD and galactose as the effective component of Rehmannia glutinosa Libosch. that protects against ALF.

CONCLUSIONS

XJDHD inhibits TNF-α-induced apoptosis of hepatocytes by promoting the expression of nuclear factor κ B-regulated anti-apoptotic genes. Rehmannia glutinosa Libosch. is the effective herb of XJDHD and galactose is an active component in this protection.

Platelet-targeted microbubbles inhibit re-occlusion after thrombolysis with transcutaneous ultrasound and microbubbles

Microbubbles (MBs) can augment the acoustic cavitation' (US), thereby facilitating the thrombolysis of external ultrasound. But we observed re-thrombosis after successful thrombolysis by MBs and transcutaneous ultrasound in an endothelium injury model. This study was designed to explore whether platelet-targeted MBs can prevent the reformation of thrombi. Arterial injury was induced in canine femoral arteries with balloon, and the arteries were completely thrombotically occluded. The arteries were treated with intra-arterial MBs or platelet-targeted MBs (TMB) and transcutaneous low frequency ultrasound (LFUS) to achieve complete thrombolysis. The arterial flow was monitored with angiogram for 4h following treatment. Results showed that both MBs and TMBs produced successful dissolution of clots in the presence of ultrasound. The re-occlusion began to occur 1h after thrombolysis in MB/LFUS treatment, and 7 of 8 arteries were re-occluded within 3h. Most of the arteries (7 of 8) in the TMB/LFUS group remained patent for 4h following treatment. The flow tended to decrease after thrombolysis in MB/LFUS treatment. These results indicated that platelet-targeted microbubbles were beneficial in preventing re-thrombosis in vivo and microbubbles served as good carrier of thrombolytic and anticoagulation drugs.

Water and phosphorus content affect PAH dissipation in spiked soil planted with mycorrhizal alfalfa and tall fescue

Polycyclic aromatic hydrocarbon (PAH) dissipation efficiency can be increased in the plant rhizosphere, but may be affected by various environmental factors. We investigated the effects of the watering regime and phosphorus concentration on PAH dissipation in the rhizosphere of mycorrhizal plants in a pot experiment. Two plant species, alfalfa (Medicago sativa) and tall fescue (Festuca arundinacea), were co-cultured and inoculated with an arbuscular mycorrhizal (AM) fungus (Glomus intraradices) in PAH (phenanthrene (PHE)=500 mg kg(-1), pyrene (PYR)=500 mg kg(-1), dibenzo(a,h)anthracene (DBA)=65 mg kg(-1)) spiked agricultural soil for 6 weeks. Treatments with different phosphorus concentrations and watering regimes were compared. The PHE dissipation reached 90% in all treatments and was not affected by the treatments. The major finding was the significant positive impact of mycorrhizal plants on the dissipation of high molecular weight PAH (DBA) in high-water low-phosphorus treatment. Such an effect was not observed in high-water high-phosphorus and low-water low-phosphorus treatments, where AM colonization was very low. A positive linear relationship was detected between PYR dissipation and the percentage of Gram-positive PAH-ring hydroxylating dioxygenase genes in high-water high-phosphorus treatments, but not in the other two treatments with lower phosphorus concentrations and water contents. Such results indicated that the phosphorus and water regime were important parameters for the dissipation of HMW-PAH.

Influence of guanidine on proteinase K resistance in vitro and infectivity of scrapie prion protein PrP(Sc)

As the scrapie prion protein PrP(Sc) is rich in beta-sheets it aggregates into prion rods, which show infectivity and proteinase K (PK) resistance. Consequently, dissociation of prion rods and breakdown of beta-sheets in PrP(Sc) by denaturation results in loss of both infectivity and PK-sensitivity. In this study, the effects of guanidine (Gdn), which solubilizes and denatures proteins by breaking down their higher structure, on the solubility, the PK-resistance in vitro and the infectivity of PrP(Sc) of scrapie strain 263K was examined. The infectivity was assayed by intracerebral inoculation into hamsters. Brain tissues of scrapie-infected hamsters were used for preparation of homogenates and crude extracts of PrP(Sc). A treatment of PrP(Sc) with Gdn enhanced its PK-sensitivity in a dose-dependent manner. The PK-resistance in vitro of PrP(Sc) denatured with lower concentrations of Gdn (<2.5 mol/l) could partially resume by renaturation. Gdn markedly reduced or, at higher concentrations, even destroyed the infectivity of PrP(Sc). On the other hand, the infectivity of PrP(Sc) inactivated by denaturation could be partially restored by renaturation. These results confirmed our assumption that all the alternations in the PK-resistance and the infectivity of PrP(Sc) caused by Gdn resulted from changes in its higher structure. However, it should be emphasized that a complete loss of PK-resistance of PrP(Sc) may not necessarily mean its full non-infectivity.

Applied anatomy of the V-shaped fibular osteomyocutaneous flap in reconstruction of the hindfoot

To establish the applied anatomy of the V-shaped fibular osteomyocutaneous flap pedicled on the peroneal vessels, cadaver dissections were made in 60 lower limbs and 40 calcanei were examined to sum up the features of calcaneal biomechanics on the stability of the foot and the blood supply of the fibular osteomyocutaneous flap. There were four anastomoses and large communicating branches between the lower segment of the peroneal artery and the anterior and posterior tibial arteries. The flap was well supplied by a retrograde circulation through these anastomoses. A suitable length of pedicle was 20 cm. In the sagittal section of the calcaneus passing through the center of the articular surface for the cuboid bone, the arrangement of the trabeculae formed a triangular zone. The V-shaped flap corresponds nicely with the calculated lines of stress evoked by the weight of the body. The procedure may provide a new method for hindfoot reconstruction. This flap meets the criteria outlined for composite tissue reconstruction of defects of the extremities and biomechanics of the hindfoot, especially for calcaneal and cuboid defects.

A molecular switch for specific stimulation of the BKCa channel by cGMP and cAMP kinase

The cGMP and the cAMP pathways control smooth muscle tone by regulation of BK(Ca) (BK) channel activity. BK channels show considerable diversity and plasticity in their regulation by cyclic nucleotide-dependent protein kinases. The underlying molecular mechanisms are unclear but may involve expression of splice variants of the BK channel alpha subunit. Three isoforms, BK(A), BK(B), and BK(C), which were cloned from tracheal smooth muscle, differed only in their C terminus. When expressed in HEK293 cells, cGMP kinase (cGK) but not cAMP kinase (cAK) stimulated the activity of BK(A) and BK(B) by shifting the voltage dependence of the channel to more negative potentials. In contrast, BK(C) was exclusively stimulated by cAK. BK(C) lacks a C-terminal tandem phosphorylation motif for protein kinase C (PKC) with Ser(1151) and Ser(1154). Mutation of this motif in BK(A) switched channel regulation from cGK to cAK. Furthermore, inhibition of PKC in excised patches from cells expressing BK(A) abolished the stimulatory effect of cGK but allowed channel stimulation by cAK. cAK and cGK phosphorylated the channel at different sites. Thus, phosphorylation/dephosphorylation by PKC determines whether the BK channel is stimulated by cGK or cAK. The molecular mechanisms may be relevant for smooth muscle relaxation by cAMP and cGMP.

Effects of doxorubicinol on excitation--contraction coupling in guinea pig ventricular myocytes

The cardiotoxicity of the anticancer drug doxorubicin may be related to its main metabolite doxorubicinol. In this study, the acute effects of doxorubicinol on excitation-contraction coupling in isolated guinea pig ventricular myocytes were investigated and compared with doxorubicin using the whole-cell patch-clamp-, fura-2 fluorescence- and cell-edge tracking techniques. Both drugs were applied intracellularly by diffusion from the patch electrode for 15--20 min. Doxorubicin (100 microM) prolonged the action potential duration (APD) by 31% and enhanced cell shortening by 26%. Contrary to doxorubicin, doxorubicinol (10 microM) shortened APD by 25% and decreased cell shortening by 31%. APD shortening by doxorubicinol was due to an increase of the delayed rectifier K(+) current. Neither the inward rectifier K(+) current nor the L-type Ca(2+) current was influenced by doxorubicinol. The decline in cell shortening induced by doxorubicinol was not exclusively due to APD shortening because doxorubicinol reduced the peak Ca(2+) transient by 23% in cells clamped with an action potential of constant duration. Despite opposite effects on APD and contractility, both doxorubicin and doxorubicinol produced a considerable delay in the activation and inactivation of contraction and Ca(2+) transient, compatible with an impaired function of the sarcoplasmic reticulum. It is suggested that doxorubicinol-induced APD shortening may amplify the detrimental effects of both doxorubicin and doxorubicinol on sarcoplasmic reticulum Ca(2+) load and hence on contractile function. The accumulation of doxorubicinol in the cardiac myocytes may play an important role in the time-dependent development of doxorubicin-induced ventricular dysfunction.

BK(Ca) channel activation by membrane-associated cGMP kinase may contribute to uterine quiescence in pregnancy

We investigated the influence of pregnancy on large-conductance calcium-activated potassium channel (BK(Ca)) activity (NP(o)) and on channel expression in membranes of isolated human myometrial smooth muscle cells. NP(o) in inside-out patches was higher in pregnant myometria (PM) compared with nonpregnant myometria (NPM), and the half-maximal activation potential was shifted by 39 mV to more negative potentials. This effect was not due to an enhanced BK(Ca) channel expression. In the presence of cAMP kinase (PKA) or cGMP kinase (PKG), NP(o) increased in patches from PM but decreased in those from NPM. Western blot analysis and use of a specific PKG inhibitor (1 microM KT-5823) verified the existence of a partially active membrane-associated PKG. Inhibition of PKA by 100 nM PKI, the inhibitory peptide of PKA, had no effect on NP(o). 8-p-Chlorophenylthio-cGMP (8-pCPT-cGMP) hyperpolarized cells from PM. This effect was abolished by iberiotoxin, a specific blocker of BK(Ca) channels. It is concluded that an endogenous, membrane-bound PKG in myometrial cells specifically enhances BK(Ca) channel activity during pregnancy and thus may contribute to uterine quiescence during pregnancy.

[Effect of heparinoid derived from porcine duodenum on the proliferation of cultured smooth muscle cells]

AIM

To study the antiproliferative effect of haparinoid derived from porcine duodenum (heparinoid) on cultured vascular smooth muscle cells.

METHODS

Cultured bovine aortic smooth muscle cells (BASMCs) of 5-10 passages were seeded into 24 and 72-well cluster culture plates and were synchronized by 48 h serum deprivation. Then, the cells were re-stimulated by serum repletion with or without heparinoid. The antiproliferative effect of heparinoid was evaluated by crystal violet staining and MTT assay 72 h after serum repletion. To study the drug action on cytomorphological changes, three kinds of cells [quiescent cells, cells treated with 10% fetal calf serum (FCS) with or without heparinoid] were observed by transmission electron microscopy. After synchronized and re-stimulated as above, BASMCs were treated with heparinoid 0.8 mg.mL-1 at selected points during serum repletion. The cells were harvested at specified times after serum repletion, then cellular DNA contents (to estimate the proportions of cells in different phases of the cell cycle) and the contents of alpha-actin, c-myc and c-fos proteins were measured by flow cytometry.

RESULTS

Heparinoid was shown to inhibit the proliferation of BASMCs induced by 10% FCS. The inhibitory effect was weakened when heparinoid was added 2 h after serum repletion, and there was no antiproliferative effect when heparinoid was added 12 h after serum repletion. Electron micrographs showed that cells treated with 10% FCS and heparinoid expressed a contractile phenotype, while cells treated with 10% FCS only expressed a synthetic phenotype. Flow cytometry study showed remarkable increase of alpha-actin, and decrease of c-myc and c-fos proteins in the cells treated with heparinoid.

CONCLUSION

Heparinoid was found to inhibit the proliferation of BASMCs. The antiproliferative effect occurred at the early phase of the cell cycle. It might be due to the drug's influence on cell phenotype modulation and the down regulation of c-myc and c-fos proto-oncogenes expression.

Polarity exchange at the interface of regulators of G protein signaling with G protein alpha-subunits

RGS proteins are GTPase-activating proteins (GAPs) for G protein alpha-subunits. This GAP activity is mediated by the interaction of conserved residues on regulator of G protein signaling (RGS) proteins and Galpha-subunits. We mutated the important contact sites Glu-89, Asn-90, and Asn-130 in RGS16 to lysine, aspartate, and alanine, respectively. The interaction of RGS16 and its mutants with Galpha(t) and Galpha(i1) was studied. The GAP activities of RGS16N90D and RGS16N130A were strongly attenuated. RGS16E89K increased GTP hydrolysis of Galpha(i1) by a similar extent, but with an about 100-fold reduced affinity compared with non-mutated RGS16. As Glu-89 in RGS16 is interacting with Lys-210 in Galpha(i1), this lysine was changed to glutamate for compensation. Galpha(i1)K210E was insensitive to RGS16 but interacted with RGS16E89K. In rat uterine smooth muscle cells, wild type RGS16 abolished G(i)-mediated alpha(2)-adrenoreceptor signaling, whereas RGS16E89K was without effect. Both Galpha(i1) and Galpha(i1)K210E mimicked the effect of alpha(2)-adrenoreceptor stimulation. Galpha(i1)K210E was sensitive to RGS16E89K and 10-fold more potent than Galpha(i1). Analogous mutants of Galpha(q) (Galpha(q)K215E) and RGS4 (RGS4E87K) were created and studied in COS-7 cells. The activity of wild type Galpha(q) was counteracted by wild type RGS4 but not by RGS4E87K. The activity of Galpha(q)K215E was inhibited by RGS4E87K, whereas non-mutated RGS4 was ineffective. We conclude that mutation of a conserved lysine residue to glutamate in Galpha(i) and Galpha(q) family members renders these proteins insensitive to wild type RGS proteins. Nevertheless, they are sensitive to glutamate to lysine mutants of RGS proteins. Such mutant pairs will be helpful tools in analyzing Galpha-RGS specificities in living cells.

Effects of mitoxantrone on excitation-contraction coupling in guinea pig ventricular myocytes

The mechanisms of the inotropic effect of mitoxantrone (MTO), a synthetic dihydroxyanthracenedione derivative with antineoplastic activity, was investigated in guinea pig ventricular myocytes using whole-cell patch-clamp methods combined with fura-2 fluorescence and cell-edge tracking techniques. In right ventricular papillary muscles, 30 microM MTO increased isometric force of contraction as well as action potential duration (APD) in a time-dependent manner. The force of contraction was increased approximately 3-fold within 4 h. This positive inotropic effect was accompanied by a prolongation of time to peak force and relaxation time. In current-clamped single myocytes treated with 30 microM MTO for 30 min, an increase of cell shortening by 77% and a prolongation of APD by 19% was observed. Peak amplitude of the intracellular Ca(2+) transients was also increased by 10%. The contribution of APD prolongation to the enhancement of cell shortening induced by MTO was assessed by clamping control myocytes with action potentials of various duration. Prolongation of APD(90) (ADP measured at 90% of repolarization) by 24% led to an increase of cell shortening by 13%. When the cells were clamped by an action potential with constant APD, MTO still caused an increase of cell shortening by 59% within 30 min. No increase of the peak intracellular Ca(2+) transients, however, was observed under this condition. We conclude that both the APD prolongation and a direct interaction with the contractile proteins contributed to the positive inotropic effect of MTO.

Pregnancy switches adrenergic signal transduction in rat and human uterine myocytes as probed by BKCa channel activity

1. We used large conductance Ca2+-activated K+ (BKCa) channel activity as a probe to characterize the inhibitory/stimulatory G protein (Gi/Gs) signalling pathways in intact cells from pregnant (PM) and non-pregnant (NPM) myometrium. 2. Isoprenaline (10 microM) enhanced the outward current (Iout) in PM cells and inhibited Iout in NPM cells. Additional application of the alpha2-adrenoceptor (alpha2-AR) agonist clonidine (10 microM) further enhanced the isoprenaline-modulated Iout in PM cells but partially antagonized Iout in NPM cells. Clonidine alone did not affect Iout. The specific cAMP kinase (PKA) inhibitor H-89 (1 microM) abolished the effects of isoprenaline and clonidine. The specific BKCa channel blocker iberiotoxin (0.1 microM) inhibited Iout by approximately 80 %; the residual current was insensitive to isoprenaline. 3. Inhibition of Gi activity by either pertussis toxin or the GTPase activating protein RGS16 abolished inhibitory as well as stimulatory effects of clonidine on Iout. 4. Transducin-alpha, a scavenger of Gi betagamma dimers, converted the stimulatory action of clonidine on Iout into an inhibitory effect. Free transducin-betagamma enhanced both the stimulatory and the inhibitory effects of isoprenaline on Iout. 5. The results demonstrate that BKCa channel activity is a sensitive probe to follow adenylyl cyclase-cAMP-PKA signalling in myometrial smooth muscle cells. Both Gialpha-mediated inhibition and Gibetagamma-mediated stimulation can occur in the same cell, irrespective of pregnancy. It is speculated that the coupling between alpha2-AR and Gi proteins is more efficient during pregnancy and that Gibetagamma at high levels simply override the inhibitory action of Gi alpha.

[Relation between myocardial cAMP and renin-angiotensin system activation after acute pressure overload]

In order to investigate the relationship between cAMP and myocardial renin-angiotensin system activation after acute pressure overload, an animal model of acute pressure overload was established by constriction of abdominal aorta. It was found that angiotensin converting enzyme (ACE) mRNA and protein expression were increased markedly, ACE activity and angiotensin II content were also elevated significantly in rat heart 1 h after acute pressure overload, and the increases were kept at high level. Meanwhile the myocardial cAMP concentration was increased significantly at 0.5 h, reached the peak at day 5, and returned to normal at day 30 after operation. Then cardiomyocytes were cultured to observe whether ACE gene expression can be induced by cAMP. The results showed that elevation of cAMP content in cultured cardiomyocytes stimulated by isoproterenol (ISO, 0.01 micromol/L) increased ACE mRNA and protein expression, and also increased ACE activity and Ang II content in cultural medium. These results suggest that cAMP plays a role in the mechanism of activation of myocardial renin-angiotensin system induced by pressure overload.

User acceptability of a female condom (Reality) in Shanghai

Thirty married couples evaluated the Reality female condom on questionnaires about its acceptability for 300 acts of coitus (10 per couple). An analysis of the summary questionnaires showed: 90% of couples considered the female condom an acceptable method and 87% felt it was a good contraceptive device; the majority of couples (87%) found it easy to use; and 80% of females and 73% of males reported that, in comparison with the male condom, the effect on sexual pleasure was either improved or no different. A little more than half of the couples (55%) preferred it to male condoms. To look at the learning curve effect, an additional analysis was completed by pooling the first 5 applications of each user and comparing the results with the pooled results of the second 5 uses. All the findings suggest that a certain proportion of couples of childbearing age will choose the Reality female condom for contraception if it enters into the Chinese market. As a new contraceptive barrier device, the female condom may require a certain amount of education and awareness before it will be fully recognized as an important option to help prevent pregnancy as well as sexually transmitted infections.

Regulation of stably expressed and native BK channels from human myometrium by cGMP- and cAMP-dependent protein kinase

The cloned BK channel alpha subunit from human myometrium was stably expressed in Chinese hamster ovary cells, either alone (CHOalpha cells) or in combination with the auxiliary beta subunit (CHOalpha+beta cells). We studied basic channel properties and the effects of cGMP- and cAMP-dependent protein kinases on the BK channel activity. Coexpression of alpha and beta subunits enhanced the Ca2+ and voltage sensitivity of the BK channel, and decreased the inhibitory potency of iberiotoxin. Blocking and stimulating effects on BK channel activity by charybdotoxin and nitric oxide, respectively, were independent of the beta subunit. The cGMP kinase Ialpha and cAMP kinase failed to affect BK channel activity in CHOalpha and CHOalpha+beta cells at different [Ca2+]i and voltages. In contrast, BK channels in freshly isolated myometrial cells from postmenopausal women responded to cAMP kinase and cGMP kinase with a fourfold and twofold decrease in their open probability (NPo), respectively. These effects could be reversed by alkaline phosphatase and remained unaffected by the phosphatase inhibitor okadaic acid (100 nM). In 28% of myometrial cells, however, cAMP and cGMP kinases increased NPo 2-fold and 3.5-fold, respectively. This stimulation was enhanced rather than reversed by alkaline phosphatase and was abolished by 100 nM okadaic acid. The results suggest that in stably transfected CHO cells the expressed BK channel is not regulated by cAMP kinase and cGMP kinase. However, in native myometrial cells stimulatory and inhibitory regulation of BK channels by cAMP kinase and cGMP kinase was observed, suggesting that channel regulation by the protein kinases requires factors that are not provided by CHO cells. Alternatively, failure of regulation may have been due to the primary structure of the myometrial BK channel protein used in this study.

Inhibitory effects of berberine on ATP-sensitive K+ channels in cardiac myocytes

The effects of berberine on cardiac action potentials were measured in isolated guinea-pig papillary muscles exposed to hypoxia and cromakalim using the standard microelectrode technique. In addition, the patch clamp technique was used to determine the effects of berberine on cromakalim-induced outward currents in isolated ventricular myocytes and on ATP-sensitive K+ (KATP) channels in inside-out membrane patches. Berberine, at 3 microM significantly inhibited, while at 100 microM completely blocked the shortening of action potential duration and effective refractory period induced by hypoxia or cromakalim (100 microM). Under the whole-cell voltage clamp conditions, berberine (3-100 microM) attenuated or even abolished the cromakalim-elicited outward K+ currents. Berberine (3-100 microM) inhibited KATP channel activity in a concentration-dependent fashion in inside-out membrane patches exposed to 0.1 mM ATP. This inhibition appeared to be mainly due to a decrease in the open channel probability without affecting unitary conductance or the time constants for open and closed channel times. Glibenclamide (10 microM) partially blocked the hypoxia-evoked but fully reversed the cromakalim-evoked abbreviation of action potential duration and effective refractory period. Both the whole-cell outward K+ currents induced by cromakalim and the opening of single KATP channels induced by the low intracellular ATP concentration were also completely abolished by 10 microM glibenclamide. We conclude that berberine is a blocker of the cardiac KATP channel. The reported beneficial effect of berberine on ischemia-induced arrhythmias is likely attributed to its inhibition of KATP channel activation and subsequent shortening of action potential duration and effective refractory period during ischemia.

Protein phosphatase 2A is essential for the activation of Ca2+-activated K+ currents by cGMP-dependent protein kinase in tracheal smooth muscle and Chinese hamster ovary cells

The regulation of Ca2+-activated K+ channels (KCa channels) by cGMP-dependent protein kinase (cGMP kinase) and its molecular mechanism were investigated in Chinese hamster ovary (CHO) and tracheal smooth muscle cells. In CHO wild-type cells (CHO-WT cells) and in CHO cells stably transfected with cGMP kinase Ialpha (CHO-cGK cells), KCa channels with intermediate conductance (approximately 50 picosiemens) were identified. Due to the basal activity of cGMP kinase, Ca2+-activated K+ currents had a higher sensitivity toward the cytosolic Ca2+ concentration in CHO-cGK cells than in CHO-WT cells. Dialysis of the active fragment of cGMP kinase (300 n) into CHO-WT cells or of cGMP into CHO-cGK cells increased the Ca2+-activated K+ current, while the catalytic subunit of cAMP-dependent protein kinase (cAMP kinase) was without effect. In cell-attached patches obtained from freshly isolated bovine tracheal smooth muscle cells, the open state probability (NPo) of maxi-KCa channels (conductance of approximately 260 picosiemens) was enhanced by 300 microM 8-(4-chlorophenylthio)-cGMP, a specific and potent activator of cGMP kinase. In contrast, 1 microM isoprenaline, 20 microM forskolin, and 3 mM 8-bromo-cAMP failed to enhance KCa channel activity. In excised inside-out patches, only the active fragment of cGMP kinase (but not that of cAMP kinase) increased NPo when applied to the cytosolic side of the patch. The enhancement of NPo by cGMP kinase was inhibited in CHO cells as well as in tracheal smooth muscle cells by the cGMP kinase inhibitor KT 5823 (1 microM) and the protein phosphatase (PP) inhibitors microcystin (5 microM) and okadaic acid (10 nM). The catalytic subunit of PP2A (but not that of PP1) mimicked the effect of cGMP kinase on NPo in excised inside-out patches. The results show that cGMP kinase regulates two different KCa channels in two unrelated cell types by the same indirect mechanism, which requires the activity of PP2A. The regulation of the KCa channel is specific for cGMP kinase and is not mimicked by cAMP kinase.

[Effect of Japanese Ganoderma Lucidum on production of interleukin-2 from murine splenocytes]

The purpose of this study was to determine the effect of Ganoderma lucidum (GL) planted in Japan on the production of Interleukin-2 (IL-2) from murine splenocytes. It was observed that hydrocortisone (HC) 0.025-1 microgram /ml could significantly antagonize the inhibitory activity of HC and CSA to increase the production of IL-2 in vitro, P < 0.01. When the splenocytes pretreated with GL alone or in combination with HC, it was shown that pretreatment alone had no significant effect on IL-2 production, but preincubating splenocytes with HC and GL resulted in a significant increase of IL-2 production when compared with that of HC group, P < 0.01. In vivo, GL 300 mg/kg could increase the production of IL-2 when oral taken GL alone or in combination of HC.

[A comparative study on cholagogic effect of Artemisia]

The result suggests that the cholagogic effect of A. anethoides, A. haichowenesis and A. capillaris are not different significantly (P > 0.05), but the duration of action caused by anethoides and haichowenesis is longer than that caused capillaris. The cholagogic effect of A. capillaris collected in seedling, flower budding (beginning of autumn) and preflower periods were also investigated separately, and the preflower collection was found more cholagogic.