Measuring quality of reporting in systematic reviews of diagnostic test accuracy studies in medical imaging: comparison of PRISMA-DTA and PRISMA

OBJECTIVES

To compare the reporting quality measured by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses of Diagnostic Test Accuracy studies (PRISMA-DTA) vs the original PRISMA checklist for systematic reviews of diagnostic test accuracy studies in imaging and survey the use of PRISMA-DTA by researchers and endorsement by journals.

METHODS

Systematic reviews of DTA studies published in 2020 and 2021 in Quartile 1 and Quartile 3 medical imaging journals (defined by Journal Citation Reports) were identified through PubMed. The reporting of each systematic review was assessed using PRISMA-DTA, PRISMA-2009 and PRISMA-2020. The item scores and overall score were compared among the three checklists. We also examined checklist adoption by the included systematic reviews and surveyed checklist endorsement from author instructions of included journals.

RESULTS

A total of 173 systematic reviews from 66 journals were included. The use of PRISMA-DTA, compared with PRISMA-2009 and PRISMA-2020, identified more issues in the reporting of title (proportion of systematic reviews with proper reporting, 27.2% vs 98.8% vs 98.8%), abstract (39.3% vs 97.1% vs 64.7%), eligibility criteria (67.6% vs 94.2% vs 94.2%), search (28.9% vs 72.3% vs 28.9%), definitions for data extraction (14.5% vs 91.9% vs 91.9%), diagnostic accuracy measures (38.2% vs 93.6% vs 93.6%), synthesis of results (28.9% vs 89.6% vs 73.4%) and results of individual studies (40.5% vs 80.3% vs 80.3%). The overall median reporting score measured by PRISMA-DTA (72.0% (interquartile range (IQR), 66.7-77.8%)) was lower than that measured by PRISMA-2009 (88.9% (IQR, 84.0-92.6%)) and similar to that measured by PRISMA-2020 (74.1% (IQR, 66.7-77.8%)). Additionally, PRISMA-DTA was used by only 43 (24.9%) systematic reviews and endorsed by two (3.0%) journals. These trends remained consistent for reviews published in journals with diverse scientific impact.

CONCLUSIONS

The use of PRISMA-DTA may identify more reporting inadequacies compared with the original PRISMA checklists when assessing diagnostic test accuracy systematic reviews, especially in critical sections such as title, abstract and methods. However, this tool is not commonly used by researchers and is inadequately endorsed by imaging journals. Our findings suggest a strong need to use PRISMA-DTA for reporting of diagnostic test accuracy systematic reviews by authors and its endorsement by journals. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Treatment and comorbidities of patients with erectile dysfunction before and during COVID-19 in the United States: A real-world data analysis

Introduction

Objectives

Methods

Results

Conclusions

Disclosure

[Exploration of construction mode of real-world data system]

Real-world data study evidence, as an important part of evaluating the safety and effectiveness of drugs and devices, has attracted increasing attention from regulatory agencies and scholars both at home and abroad, and has become an essential source of evidence to support the development and review of drugs and devices. This paper systematically discusses the process and mode of real-world data system construction based on the preliminary practical study of real-world data according to the guidelines/technical specifications issued by regulatory agencies and academic research results. This study result provides not only reference for the generation of clinical evaluation evidence to meet the regulatory requirements for innovative drugs and devices, but also reference for researchers, sponsors and regulators to carry out real-world data studies successfully.

[Real-world data studies of medical products in the context of special healthcare policy: study designs and key considerations]

Boao Lecheng International Medical Tourism Pilot Area is the only administrative area in China where the pilot application of real-world data is performed. Based on the special healthcare policy in Boao Lecheng, conducting real-world data study to provide real-world evidence for the clinical evaluations and approvals of innovated medical products has become an important field that supports the reform of China's evaluation and approval system of medical products. Trustworthy real-world evidence needs to rely on both high-quality real-world data and reasonable and rigorous study designs. Based on the real-world data research guidelines and specifications issued by relevant academic research and regulatory authorities both at home and abroad, combined with the special policy environment of Boao Lecheng and previous practice experience, this paper summarizes the study designs of real world data in Boao Lecheng and discusses the key considerations of different study design in the context of special healthcare policies in Boao Lecheng in order to provide reference for the further study of real-world data.

[Electromyography analysis in 13 patients with acute trimethyltin chloride poisoning]

Objective: To investigate the electromyography (EMG) characteristics and clinical significance in patients with acute trimethyltin chloride (TMT) poisoning. Methods: Retrospectively analyze the EMG results of major limb nerves and muscles of 13 patients with acute TMT poisoning. Results: Among the 13 patients, 10 cases had abnormal and the abnormal rate was 76.9%. The same degree of involvement of upper and lower limbs is the most common. And distal peripheral nerve damage is the most common, mainly manifested as sensory damage or mixed sensory and motor damage, with axonal injury and demyelinating lesions to almost the same degree. The peroneal nerve and median nerve were the most vulnerable, with an abnormal rate of 39.1% and 35.9%, respectively. The peroneal nerve and median nerve were damaged first but recovered slowly.The ulnar nerve first appeared damaged and recovered quickly. The sural nerve was damaged later. Conclusion: Acute TMT poisoning can cause limb peripheral nerve damage. This damage is a slow, gradual process, and its recovery is also a slow process.

Expressions of IL-1α and MMP-9 in degenerated lumbar disc tissues and their clinical significance

OBJECTIVE

To observe the expression levels of interleukin-1α (IL-1α) and matrix metalloproteinase-9 (MMP-9) in degenerated lumbar disc tissues and to investigate their clinical significance.

PATIENTS AND METHODS

Fifty patients with lumbar disc degeneration received the operative treatment were divided into three groups according to the magnetic resonance imaging (MRI) results: protrusion group, extrusion group, and free group. The degenerated intervertebral disc tissues were taken, and the normal intervertebral disc tissues of 20 patients received the operative treatment due to lumbar bursting fracture, and were selected as the control group. The bone mineral densities of all patients were measured. The mRNA and protein expression levels of MMP-9 and IL-1α were detected via Real-time polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay (ELISA), respectively.

RESULTS

The bone mass of patients with lumbar disc degeneration was significantly decreased compared with that of the control group, and the bone mass was decreased more significantly in a free group than that in protrusion group. The mRNA and protein levels in IL-1α and MMP-9 of patients with lumbar disc degeneration were significantly increased compared with those in control group; the mRNA and protein levels in IL-1α and MMP-9 of extrusion group and free group were significantly higher than those in protrusion group, and the mRNA and protein levels in IL-1α and MMP-9 of free group were significantly higher than those in extrusion group.

CONCLUSIONS

The levels of IL-1α and MMP-9 in degenerated lumbar disc tissues are higher than normal levels, and the increasing levels are positively correlated with the disease condition.

Risk and protective factors for falls on stairs in young children: multicentre case-control study

AIM

To investigate risk and protective factors for stair falls in children aged <5 years.

METHODS

Multicentre case-control study at hospitals, minor injury units and general practices in and around four UK study centres. Cases were children with medically attended stair fall injuries. Controls were matched on age, sex, calendar time and study centre. A total of 610 cases and 2658 controls participated.

RESULTS

Cases' most common injuries were bangs on the head (66%), cuts/grazes not requiring stitches (14%) and fractures (12%). Parents of cases were significantly more likely not to have stair gates (adjusted OR (AOR) 2.50, 95% CI 1.90 to 3.29; population attributable fraction (PAF) 21%) or to leave stair gates open (AOR 3.09, 95% CI 2.39 to 4.00; PAF 24%) both compared with having closed stair gates. They were more likely not to have carpeted stairs (AOR 1.52, 95% CI 1.09 to 2.10; PAF 5%) and not to have a landing part-way up their stairs (AOR 1.34, 95% CI 1.08 to 1.65; PAF 18%). They were more likely to consider their stairs unsafe to use (AOR 1.46, 95% CI 1.07 to 1.99; PAF 5%) or to be in need of repair (AOR 1.71, 95% CI 1.16 to 2.50; PAF 5%).

CONCLUSION

Structural factors including having landings part-way up the stairs and keeping stairs in good repair were associated with reduced stair fall injury risk. Family factors including having stair gates, not leaving gates open and having stair carpets were associated with reduced injury risk. If these associations are causal, addressing these factors in housing policy and routine child health promotion could reduce stair fall injuries.

Transport studies of dual-gated ABC and ABA trilayer graphene: band gap opening and band structure tuning in very large perpendicular electric fields

We report on the transport properties of ABC and ABA stacked trilayer graphene using dual, locally gated field effect devices. The high efficiency and large breakdown voltage of the HfO(2) top and bottom gates enable independent tuning of the perpendicular electric field and the Fermi level over an unprecedentedly large range. We observe a resistance change of 6 orders of magnitude in the ABC trilayer, which demonstrates the opening of a band gap. Our data suggest that the gap saturates at a large displacement field of D ~ 3 V/nm, in agreement with self-consistent Hartree calculations. In contrast, the ABA trilayer remains metallic even under a large perpendicular electric field. Despite the absence of a band gap, the band structure of the ABA trilayer continues to evolve with increasing D. We observe signatures of two-band conduction at large D fields. Our self-consistent Hartree calculation reproduces many aspects of the experimental data but also points to the need for more sophisticated theory.

Total saponins of Tupistra chinensis induces apoptosis in A549 cells

Tupistra chinensis Baker has been used as a folk remedy in China, and it has been shown to exhibit anti-inflammation, expectorant and anti-bacterial effects. In this study, we report the cytotoxic activity of the total saponins of Tupistra chinensis Baker (TST) against several carcinoma cell lines, including A549, MCF-7 and HeLa cells with the IC50 values of 4.11 μg/ml, 6.47 μg/ml and 7.78 μg/ml respectively. Treatment of A549 cells with TST resulted in growth inhibition and induction of apoptosis in a time-dependent manners determined by cell viability, chromatin condensation, DNA fragmentation and flow cytometry analysis. The activities of caspase-3, 9 were significantly increased following TST treatment. Real-time PCR analysis showed that the mRNA expression levels of pro-apoptosis related genes including Bax, P21, P27 and P53 were markedly increased in the cells treated with TST but anti-apoptosis related gene Bcl-2 was slightly decreased. TST also leads to a loss of mitochondrial membrane potential in a time-dependent manner the release of cytochrome C from mitochondria into the cytosol. Thus, these results suggest that TST may play an important role in tumor growth suppression by inducing apoptosis in human A549 cells via mitochondria-dependent apoptotic pathways and the TST would be promising to treat human lung adenocarcinoma.

Evidence for spin-flip scattering and local moments in dilute fluorinated graphene

The issue of whether local magnetic moments can be formed by introducing adatoms into graphene is of intense research interest because it opens the window to fundamental studies of magnetism in graphene, as well as of its potential spintronics applications. To investigate this question, we measure, by exploiting the well-established weak localization physics, the phase coherence length L(Φ) in dilute fluorinated graphene. L(Φ) reveals an unusual saturation below ~10 K, which cannot be explained by nonmagnetic origins. The corresponding phase-breaking rate increases with decreasing carrier density and increases with increasing fluorine density. These results provide strong evidence for spin-flip scattering and point to the existence of an adatom-induced local magnetic moment in fluorinated graphene. Our results will stimulate further investigations of magnetism and spintronics applications in adatom-engineered graphene.

Deposition of high-quality HfO2 on graphene and the effect of remote oxide phonon scattering

We demonstrate atomic layer deposition of high-quality dielectric HfO2 films on graphene and determine the magnitude of remote oxide surface phonon scattering in dual-oxide structures. The carrier mobility in these HfO2-covered graphene samples reaches 20,000  cm2/V s at low temperature. Distinct contributions to the resistivity from surface optical phonons in the SiO2 substrate and the HfO2 overlayer are isolated. At 300 K, surface phonon modes of the HfO2 film centered at 54 meV limit the mobility to approximately 20,000  cm2/V s.

High-mobility few-layer graphene field effect transistors fabricated on epitaxial ferroelectric gate oxides

The carrier mobility mu of few-layer graphene (FLG) field-effect transistors increases tenfold when the SiO2 substrate is replaced by single-crystal epitaxial Pb(Zr0.2Ti0.8)O3 (PZT). In the electron-only regime of the FLG, mu reaches 7x10(4) cm(2)/V s at 300 K for n=2.4x10(12)/cm(2), 70% of the intrinsic limit set by longitudinal acoustic (LA) phonons; it increases to 1.4x10(5) cm(2)/V s at low temperature. The temperature-dependent resistivity rho(T) reveals a clear signature of LA phonon scattering, yielding a deformation potential D=7.8+/-0.5 eV.

Selenium for preventing Kashin-Beck osteoarthropathy in children: a meta-analysis

OBJECTIVE

To assess the efficacy of selenium supplementation for prevention of Kashin-Beck Osteoarthropathy in children.

METHODS

We searched eight electronic databases and seven journals (upto July 2007) to identify randomized controlled trials (RCTs) and prospective non-RCTs comparing selenium supplementations with placebo or no intervention for preventing Kashin-Beck disease (KBD). The methodological qualities of included studies were assessed according to the guidelines of Cochrane Handbook for Systematic Reviews of Interventions for RCTs and the method described by Deeks et al. for non-RCTs. Outcomes were presented as Peto-odds ratios (Peto-ORs) with 95% confidence intervals (95% CIs) based on fixed effect model. The number needed to treat (NNT) was calculated. Meta-regression was also conducted to explore the possible impacts of potential confounding variables (place of study, age, selenium form, etc.) of included trials on the incidence of KBD.

RESULTS

Five RCTs and 10 non-RCTs were included in this review. The methodological quality of included studies was low. The pooled Peto-OR and NNT favoring selenium supplement was 0.13 (95% CI: 0.04-0.47) and 21 in RCTs, and 0.16 (95% CI: 0.09-0.30) and 26 in non-RCTs. Meta-regression indicated that the effect of potential confounding variables on KBD incidence was not statistically significant. One trial reported the side effects of nausea and vomiting in the process of selenium supplementation.

CONCLUSIONS

Current evidence supports the benefits of selenium supplementation for prevention of KBD in children. However, the evidence was limited by potential biases and confounders. Large, well-designed trials are still needed.

A pair of isomeric saponins with cytotoxicity from Albizzia julibrissin

Two new saponins have been isolated from the stem barks of Albizzia julibrissin Durazz, and their structures identified as 3-O-[beta-D-xylopyranosyl-(1 --> 2)-beta-D-fucopyranosyl-(1 --> 6)-beta-D-2-deoxy-2-acetoamidoglucopyranosyl]-21-O-{(6S)-2-trans-2-hydroxymethyl-6-methyl-6-O-[4-O-((6S)-2-trans-2-hydroxymethyl-6-hydroxy-6-methyl-2,7-octadienoyl)-beta-D-quinovopyranosyl]-2,7-octadienoyl}-acacic acid-28-O-beta-D-glucopyranosyl-(1 --> 3)-[alpha-L-arabinofuranosyl-(1 --> 4)]-alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl ester (1) and 3-O-[beta-D-xylopyranosyl-(1 --> 2)-beta-D-fucopyranosyl-(1 --> 6)-beta-D-2-deoxy-2-acetoamidoglucopyranosyl]-21-O-{(6S)-2-trans-2-hydroxymethyl-6-methyl-6-O-[3-O-((6S)-2-trans-2-hydroxymethyl-6-hydroxy-6-methyl-2,7-octadienoyl)-beta-D-quinovopyranosyl]-2,7-octadienoyl}acacic acid 28-O-beta-D-glucopyranosyl-(1 --> 3)-[alpha-L-arabinofuranosyl-(1 --> 4)]-alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl ester (2), based on chemical and spectral evidences, named as julibroside J19 and julibroside J18, respectively. Both compounds show significant inhibition action against HeLa, Bel-7402 and MDA-MB-435 cancer cell lines in vitro.

Development and testing of a cross-sectional area measurement tool for evaluating vein size

This paper describes a software system for measuring cross-sectional area in reconstructed elliptical tubular structures. A measurement tool was developed using the freely available, cross-platform, open-source three-dimensional (3-D) Slicer environment. The software is easy to operate and allows the user to make multiple measurements on the fly. Results can be displayed to the screen, output to the system printer, and written to a user-specified data file for later analysis in commercial spreadsheet software. Measuring a known cross-sectional area tested the software. Phantoms of known physical dimensions were imaged using both CT and MR. The measured cross-sectional areas reported by the software were compared to each other, and the cross-sectional areas calculated from the known physical dimensions of the phantoms. The measurement errors were negligible. The results of this study indicate that the cross-sectional area measurement tool described provides reliable measurements and is an inexpensive and versatile alternative to high-end 3-D modeling software.

Association study of an SNP combination pattern in the dopaminergic pathway in paranoid schizophrenia: a novel strategy for complex disorders

Schizophrenia is a common mental disorder with a complex pattern of inheritance. Despite a large number of studies in the past decades, its molecular etiology remains unknown. In this study, we proposed a 'system-thinking' strategy in seeking the combined effect of susceptibility genes for a complex disorder by using paranoid schizophrenia as an example. We genotyped 85 reported single-nucleotide polymorphisms (SNPs) present in 23 genes for the dopamine (DA) metabolism pathway among 83 paranoid schizophrenics and 108 normal controls with detailed clinical and genetic information. We developed two novel multilocus approaches-the potential effective SNP combination pattern and potential effective dynamic effects analysis, by which three susceptibility genotype combinations were found to be associated with schizophrenia. These results were also validated in a family-based cohort consisting of 95 family trios of paranoid schizophrenia. The present findings suggest that the COMT and ALDH3 combination may be the most common type involved in predisposing to schizophrenia. Since the combination blocks the whole pathways for the breakdown of DA and noradrenaline, it is very likely to play a central role in developing paranoid schizophrenia.

Clinical significance and assessment of cytokines in various stages of ulcerative colitis

In order to study the clinical significance and change of interleukin (IL)-1 beta and IL-10 concentration in intestinal mucosal tissues in various stage of ulcerative colitis (UC), IL-1 beta and IL10 levels were measured by enzyme linked immunosorbent assays (ELISA). Our results showed that IL-beta level caused by spontaneous secretion in the intestinal mucous tissues in active stage of ulcerative colitis was significantly higher than that in normal controls and in remission stage of ulcerative colitis (P < 0.01, P < 0.001). IL-10 level in various stage of UC was relatively lower in controls, but there was no significantly difference between the two groups. Our study suggested that higher IL-1 beta level in active might play an important role in pathogenesis of UC, and IL-10, as an anti-inflammatory cytokine, was low in active UC, suggesting that it may be a important factor contributing to the development of higher IL-1 beta level.

Focal nodular hyperplasia of the liver: detection and characterization with plain and dynamic-enhanced MRI

BACKGROUND

We compared nonenhanced and dynamic gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) appearances of hepatic focal nodular hyperplasia (FNH) as depicted with breath-hold MR sequences and assessed the detectability of the individual MR sequences used.

METHODS

We retrospectively reviewed 48 consecutive patients with FNH. All patients underwent nonenhanced (T1 fast low-angle shot [FLASH] and T2 half-Fourier acquisition [HASTE]) and dynamic Gd-enhanced (T1 FLASH) MRI between December 1997 and March 2000. Individual MR sequences were analyzed separately for number of lesions, signal intensity features, dynamic enhancement pattern, and the presence and enhancement profile of a central scar. Ninety-five percent confidence intervals of absolute discrepancy were calculated to define differences in lesion detection.

RESULTS

Seventy-seven lesions were found in 48 patients. Nonenhanced FLASH imaging depicted 59 (76.6%) lesions in 45 patients. HASTE images showed 55 (71.4%) lesions in 44 patients. On T1- and T2-weighted images, lesions appeared predominantly hypointense (69.5%) and hyperintense (72.7%), respectively. Arterial and portal venous dominant phase Gd-enhanced MRI demonstrated all 77 lesions (100%), most of which showed hypervascular (94.8%), homogeneous (97.4%), and incomplete (except the central scar: 58.4%) enhancement in the arterial phase. Portal venous phase images showed lesion isointensity (50.6%) or moderate hyperintensity (46.8%) with complete enhancement (central scar: 94.8%). A central scar was detected on nonenhanced T1-weighted images (hypointense: 100%), T2-weighted images (hyperintense: 100%), arterial phase (hypointense: 59.7%) and portal venous phase (hyperintense: 71.4%) Gd-enhanced images in 78%, 69.1%, 77.9%, and 75.3% of tumors, respectively.

CONCLUSION

Arterial and portal venous phase Gd-enhanced T1-weighted sequences are superior to nonenhanced images in the detection of FNH. Typical MRI appearances include hypointensity on T1-weighted and hyperintensity on nonenhanced T2-weighted images. Most commonly, FNH shows a homogeneous (without scar) and strong enhancement during the arterial phase, with lesion isointensity or slight hyperintensity during the portal venous phase.

Midkine binds to 37-kDa laminin binding protein precursor, leading to nuclear transport of the complex

Midkine (MK) is a heparin binding multifunctional protein that promotes cell survival and cell migration. MK was found to bind to 37-kDa laminin binding protein precursor (LBP), a precursor of 67-kDa laminin receptor, with K(d) of 1.1 nM between MK and LBP-glutathione-S-transferase fusion protein. The binding was inhibited by laminin, anti-LBP, amyloid beta-peptide, and heparin; the latter two are known to bind to MK. In CMT-93 mouse rectal carcinoma cells, LBP was mostly located in the cytoplasm as revealed by immunostaining with anti-LBP antibody. That a portion of LBP or 67-kDa laminin receptor was located at the surface of these cells was verified by inhibition of cell attachment to laminin-coated dishes by anti-LBP antibody. When MK was added to culture medium of these cells, a part of LBP migrated to the nucleus. The movement occurred concomitantly with nuclear transport of biotin-labeled MK. These findings suggested that the binding of MK to LBP caused nuclear translocation of the molecular complex.

Two- and 3-dimensional MRI comparison of levator ani structure, volume, and integrity in women with stress incontinence and prolapse

OBJECTIVE

The aim of this study was to identify imaging markers for genuine stress incontinence and pelvic organ prolapse by using magnetic resonance imaging and reconstructed 3-dimensional models.

STUDY DESIGN

Thirty women were studied, 10 with prolapse, 10 with genuine stress incontinence, and 10 asymptomatic volunteers. Axial and sagittal T1 and T2 weighted pelvic magnetic resonance scans were obtained with the patient in the supine position. Source images were measured to determine levator hiatus height, bladder neck to pubococcygeal line, levator plate angle, and perineal descent at rest and maximum Valsalva. Manual segmentation and surface modeling was applied to build 3-dimensional models of the organs. The 3-dimensional models were measured to determine levator muscle volume, shape and hiatus width, distance between symphysis and levator sling muscle, posterior urethrovesical angle, bladder neck descent, and levator plate angle.

RESULTS

The 3 groups of subjects were comparable in age, parity, and body mass index. In the control, genuine stress incontinence, and prolapse groups, the menopausal rate was 40%, 60%, and 55% (P =.7). In the same order, significant mean 2-dimensional measures were: resting bladder neck descent of 24, 17, and 3 mm (P <.005), straining levator plate angle of -4.3, -11.5, and -31 degrees (P =.01), straining levator hiatus height of 48.5, 51.1, and 65.3 mm (P <.005), and straining perineal descent of 17.2, 22.5, 27.2 mm (P =.02). Similarly ordered mean 3-dimensional parameters showed levator volumes of 32.2, 23.3, and 18.4 cm(3) (P <.005); hiatus widths of 25.7, 34.7, and 40.3 mm (P <.005); left levator sling muscle gaps of 15.6, 20.3, and 23.8 mm (P =.03), right levator sling muscle gaps of 15.6, 22.5, and 30.8 mm, (P = 0.003), and levator shape (90%, 40%, and 20% dome shaped; P <.005).

CONCLUSION

Both 2-dimensional magnetic resonance images and 3-dimensional models yield findings that differ among asymptomatic subjects compared with those with genuine stress incontinence and prolapse. Our 3-dimensional data demonstrate a statistically significant continuum in levator volume, shape, and integrity across groups of asymptomatic, genuine stress incontinence, and prolapse subjects.

[Two new flavanone glycosides from Glycyrrhizia inflata]

Two new flavanone glycosides having two chains of sugar moeity were isolated from the roots of Glycyrrhizia inflata Bat by repeated CC and HPLC. They were identified to be liquiritigenin-7-O-beta-D-apiofuranosyl-4'-O-beta-D-glucopyranoside(I) and liquiritigenin-7-O-beta-D-(3-O-acetyl)-apiofuranosyl-4'-O-beta-D- glucopyranoside (II) on the basis of chemical and spectroscopic methods.

A heparin-binding growth factor, midkine, binds to a chondroitin sulfate proteoglycan, PG-M/versican

Midkine is a heparin-binding growth factor with survival-promoting and migration-enhancing activities. In order to understand the regulation of midkine signaling, we isolated midkine-binding proteoglycans from day 13 mouse embryos, when midkine is intensely expressed. Deglycosylation followed by SDS/PAGE revealed various protein bands; one of these was identified as PG-M/versican by in gel trypsin digestion and sequencing the resulting peptides. PG-M/versican isolated from day 13 mouse embryos bound midkine with a Kd of 1.0 nM. Pleiotrophin/heparin-binding growth-associated molecule, which has a structure related to midkine, was also bound similarly. Digestion with chondroitinase ABC, AC-I or B abolished the binding to midkine. Heparin as well as chondroitin sulfate D and E inhibited the binding. After chondroitinase ABC digestion, the midkine-binding PG-M/versican released 4-sulfated, 6-sulfated, 2, 6-disulfated and 4,6-disulfated unsaturated disaccharides. These results suggest that midkine binds to a polysulfated domain in the chondroitin sulfate chain with a region of dermatan sulfate structure. This proteoglycan may modulate the midkine activity, as binding to midkine can enhance midkine action by concentrating it to the cell periphery or inhibit the action by competing with the binding to a signaling receptor.

LDL receptor-related protein as a component of the midkine receptor

Midkine (MK) is a heparin-binding growth factor with migration-promoting and survival-promoting activities. To identify signaling receptor(s) of MK, membrane glycoproteins with MK-binding activity were isolated from day 13 mouse embryos by lectin- and MK-affinity chromatography. SDS-PAGE followed by protein sequence analysis revealed the presence of LDL receptor-related protein (LRP) and NCAM in the fraction. The dissociation constant of binding between LRP and MK was 3.5 nM. Receptor-associated protein (RAP), which interfered with the binding, inhibited MK-dependent survival of embryonic neurons. Brushin/megalin, which is also a high molecular weight protein belonging to the LDL receptor family, bound to MK less strongly than LRP. These findings suggest that LRP is a component of the receptor complex for MK.

Two diastereomeric saponins with cytotoxic activity from Albizia julibrissin

Two diastereomeric saponins, julibrosides J1 (1) and J9 (2), both of which show cytotoxic activity, were obtained from the stem bark of Albizia julibrissin Durazz. On the basis of chemical and spectral evidence [L.B. Ma et al., Carbohydr. Res., 281 (1996) 35-46], the structure of 1 was revised as 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6) -beta-D-glucopyranosyl]-21-O-[(6S)-2-trans-2-hydroxymethyl-6-methyl-6-O- [4-O-((6R)-2-trans-2,6-dimethyl-6-O-(beta-D-quinovopyranosyl)-2,7- octadienoyl)-beta-D-quinovopyranosyl]-2,7-octadienoyl] acacic acid-28-O-beta-D-glucopyranosyl-(1-->3)-[alpha-L-arabinofuranosyl-(1-->4 )]-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl ester. The diastereoisomer 2 of 1 was identified as 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6) -beta-D-glucopyranosyl]-21-O-[(6S)-2-trans-2-hydroxymethyl-6-methyl-6-O- [4-O-((6S)-2-trans-2,6-dimethyl-6-O-(beta-D-quinovopyranosyl)-2,7- octadienoyl)-beta-D-quinovopyranosyl]-2,7-octadienoyl] acacic acid-28-O-beta-D-glucopyranosyl-(1-->3)-[alpha-L-arabinofuranosyl-(1-->4 )]-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl ester. Saponin 2 is a new saponin named julibroside J9. Both julibrosides J1 and J9 show good inhibitory action against the KB cancer cell line in vitro.

[The structure identification of Julibroside J6 from Albizia julibrissin Durazz]

OBJECTIVE

To study the saponin from Albizia julibrissin.

METHODS

A saponin was separated by using chromatography and its structure was elucidated on the basis of spectral data.

RESULTS

A saponin was obtained and it's structure was identified as 3-O-[beta-D-xylopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-(1-->6)-beta- D-2-deoxy-2-acetamidoglucopyranosyl]-21-O-(6S-2-trans-2-hydroxymethyl- 6-methyl-6-O-[4-O-(6S-2-trans-2-hydroxymethyl-6-methyl-6-hydroxy-2, 7-octadienoyl)-beta-D-quinovopyranosyl]-2, 7-octadienoyl)-acacic acid-28-O-beta-D-glucopyranosyl(1-->3)-[alpha-L-arabinofuranosyl- (1-->4)]-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosyl ester.

CONCLUSION

The saponin is a new compound named Julibroside J6.

Study on gastric empty disorder after the gastric ulcer healing and therapeutic effect of cisapride

Gastric emptying time of liquid meal was detected by using ultrasonography in 28 gastric ulcer patients with continual or recurrent dyspepsia symptoms after the ulcer healing. Sixteen out of 28 patients (57.1%) with a delay of gastric emptying time (T1/2) were randomly divided into two groups: 8 cases were treated with cisapride 5 mg three times a day and 8 cases with cisapride 10 mg three times a day respectively. The results showed that cisapride could relieve the symptoms with the effective rate being 68.8% in the two groups. T1/2 in the patients after treatment with cisapride was significantly shorter than before treatment (P < 0.001). It was concluded that there is a delay of T1/2 in some patients with gastric ulcer healing. Cisapride could promote gastric empty of liquid meal and relieve the symptoms efficiently. The effect of lower dose of cisapride is similar to that of higher dose.

A study of anorectal manometry in patients with chronic idiopathic constipation

To study the changes of anorectal motility in patients with chronic idiopathic constipation, anorectal motility was investigated by water-perfused manometric system in 30 patients with chronic idiopathic constipation and 18 healthy subjects. Our results showed that there was no significant difference between the constipation group and the control group in anal sphincteric resting pressure and anal maximal squeezing pressure. The minimum relaxation volume, the rectal defecatory threshold, the rectal maximal tolerable volume and the rectal compliance in the patients were significantly higher than those in the controls (P < 0.01 or P < 0.05). It is concluded that patients with chronic idiopathic constipation have anorectal motility disturbances.

Midkine is expressed during repair of bone fracture and promotes chondrogenesis

Midkine (MK) is a heparin-binding growth/differentiation factor implicated in the control of development and repair of various tissues. Upon fracture of the murine tibia, MK was found to be transiently expressed during bone repair. MK was immunohistochemically detected in spindle-shaped mesenchymal cells at the fracture site on day 4 after fracture and in chondrocytes in the area of endochondral ossification on day 7. MK expression was decreased on day 14 and scarcely seen on day 28 when bone repair was completed. This mode of MK expression is reminiscent of MK expression during development. MK was expressed in hypertrophic chondrocytes of the prebone cartilage rudiments on embryonic day 14 in mouse embryos. MK was also strongly expressed in the epiphyseal growth plate. MK was localized intracellularly during both bone repair and development, and this localization was confirmed by immunoelectron microscopy for embryonic chondrocytes. When MK cDNA was transfected into ATDC5 chondrogenic cells and overexpressed, the majority of transfected cells with strong MK expression showed enhanced chondrogenesis as revealed by increased synthesis of sulfated glycosaminoglycans, aggrecan, and type II collagen. These results suggest that MK plays important roles in chondrogenesis and contributes to bone formation and repair.

Isolation and characterisation of neurotoxigenic Clostridium butyricum from soil in China

Soil specimens collected from a site around the home of patients with food-borne type E. botulism probably caused by neurotoxigenic Clostridium butyricum in Guanyun, Jiangsu province, China, were examined for the presence of neurotoxigenic C. butyricum. Five lakeside sites of Weishan lake, in an area near to the sites where the type E. botulism outbreaks caused by neurotoxigenic C. butyricum occurred were also surveyed. Type E toxin-producing C. butyricum was isolated from soil from four sites including the site in Guanyun. Polymerase chain reaction assay demonstrated the presence of the type E toxin gene in all the toxigenic isolates. The biochemical properties of the isolates from the Guanyun soil and the lakeside soil were identical except for inulin fermentation and starch hydrolysis properties. These results indicate that neurotoxigenic C. butyricum has its principal habitat in soil.

A triterpenoid saponin from Albizia julibrissin

A triterpenoid saponin (1) was obtained from the stem barks of Albizia julibrissin Durazz. Its structure was elucidated as 3-O-[beta-D-xylopyranosyl-(1 --> 2)-alpha-L-arabinopyranosyl-(1 --> 6)-beta-D-glucopyranosyl]-21-O-[(6S)-2-trans-2-hydroxymethyl-6-methyl-6-O-beta-D-quinovopyranosyl-2, 7-octadienoyl]-16-deoxy-acacic acid 28-O-beta-D-glucopyranosyl-(1 --> 3)-[alpha-L-arabinofuranosyl-(1 --> 4)]-alpha-L-rhamnopyranosyl-(1 --> 2)-beta-D-glucopyranosyl ester (1), named as Julibroside J26, based on the chemical and spectral methods.

Oestradiol up-regulates oestrogen receptor, cyclophilin, and glyceraldehyde phosphate dehydrogenase mRNA concentrations in endometrium, but down-regulates them in liver

Oestradiol regulates reproductive physiology and cardiovascular health in women. In the endometrium of ovariectomized ewes, previous work demonstrated that a single dose of oestradiol (50 microg) up-regulates oestrogen receptor-alpha (ER) and progesterone receptor (PR) gene expression within 24 h. Here we compared responses to different doses of oestradiol and different dosing regimens in two diverse tissues: endometrium and liver. ER, c-fos, cyclophilin and glyceraldehyde phosphate dehydrogenase (GAPDH) mRNA concentrations were analyzed on replicate RNA slot blots in both tissues, while PR and apolipoprotein AI (apo AI) mRNA concentrations were only analyzed in endometrium or liver, respectively. Along with ER mRNA, oestradiol strongly up-regulated GAPDH and cyclophilin mRNA concentrations in endometrium. In liver, however, oestradiol down-regulated them, along with apo AI mRNA. Responses to different doses and dose regimens, including repeated 50 microg doses, were similar to those evoked by a single 50 microg dose of oestradiol. Thus, oestradiol appears to have all-or-none effects which include up-regulation of ER, cyclophilin and GAPDH gene expression in endometrium and down-regulation of ER, apo AI, cyclophilin and GAPDH gene expression in liver. These results illustrate the sharp contrast between two mammalian tissues in their responses to physiological levels of oestradiol.

Characterization of a neurotoxigenic Clostridium butyricum strain isolated from the food implicated in an outbreak of food-borne type E botulism

Neurotoxigenic Clostridium butyricum was isolated from the food implicated in an outbreak of clinically diagnosed type E botulism in China. PCR assay showed that the isolate (LCL 155) contained the type E botulinum toxin gene. This appears to be the first report of neurotoxigenic C. butyricum causing food-borne botulism.