Advances in nanocellulose-based materials as adsorbents of heavy metals and dyes

In recent years, nanocellulose-based materials have been increasingly applied as a lot of biosorbents for the treatment of water pollutants due to their large specific surface area, easy modification, environmental friendliness, and reproducibility. In this review, surface modification of nanocellulose-based adsorbents with various effective adsorption groups is described, as well as polymer grafting and hybrid composite fabrication. The adsorption mechanisms involved in the adsorption process of pollutants by adsorbents are further analysed and summarized. The regeneration methods of nanocellulose adsorbents with different adsorption mechanisms are also demonstrated. In addition, this paper also briefly describes the forms of nanocellulose-based adsorbents with large-scale application including membranes, gels, flocculants and magnetic composites.

Suppression of LjBAK1-mediated immunity by SymRK promotes rhizobial infection in Lotus japonicus

An important question in biology is how organisms can associate with different microbes that pose no threat (commensals), pose a severe threat (pathogens), and those that are beneficial (symbionts). The root nodule symbiosis serves as an important model system for addressing such questions in the context of plant-microbe interactions. It is now generally accepted that rhizobia can actively suppress host immune responses during the infection process, analogous to the way in which plant pathogens can evade immune recognition. However, much remains to be learned about the mechanisms by which the host recognizes the rhizobia as pathogens and how, subsequently, these pathways are suppressed to allow establishment of the nitrogen-fixing symbiosis. In this study, we found that SymRK (Symbiosis Receptor-like Kinase) is required for rhizobial suppression of plant innate immunity in Lotus japonicus. SymRK associates with LjBAK1 (BRASSINOSTEROID INSENSITIVE 1-Associated receptor Kinase 1), a well-characterized positive regulator of plant innate immunity, and directly inhibits LjBAK1 kinase activity. Rhizobial inoculation enhances the association between SymRK and LjBAK1 in planta. LjBAK1 is required for the regulation of plant innate immunity and plays a negative role in rhizobial infection in L. japonicus. The data indicate that the SymRK-LjBAK1 protein complex serves as an intersection point between rhizobial symbiotic signaling pathways and innate immunity pathways, and support that rhizobia may actively suppress the host's ability to mount a defense response during the legume-rhizobium symbiosis.

Immunoglobulin D Multiple Myeloma with a “Hidden” Lambda Light Chain

Introduction/Objective

In rare cases, the conventional immunofixation gel electrophoresis technique fails to detect the light chain of an M-protein. We report a case of immunoglobulin (Ig) D multiple myeloma with a hidden lambda (λ) light chain.

Methods/Case Report

Capillary electrophoresis (CE) (Sebia CAPILLARYS 2) was used to detect and quantify M- proteins in serum specimens. Immunosubtraction (IS) on the CAPILLARYS 2 systems was used to identify the classes of M-proteins. Conventional gel immunofixation electrophoresis (IFE) was performed, using monospecific antisera for IgD, IgE, kappa (κ) or λ in the Sebia HYDRASYS system, and IgG, IgA, IgM, κ or λ in the Helena SPIFE3000 system. Beta-mercaptoethanol (BME) with Fluidil were used as reduction agents.

Results (if a Case Study enter NA)

Results of serum CE showed two abnormal peaks in beta 2 and gamma regions, suspected to be positive for M-proteins. IS results showed subtraction for λ light chain only in both peaks, suggesting two monoclonal λ light chains. In contrary, no monoclonal λ light chain was detected in gamma region by IFE (Sebia). Epitope masking in the folded monoclonal protein was suspected to cause the “hidden λ light chain” and was further investigated by two laboratory approaches. IFE performed on the Helena SPIFE3000 system found two λ bands in beta 2 and gamma regions, which was consistent with the results from IS. The treatment of BME with Fluidil helped unmasking the hidden epitope and revealed the λ band in gamma region on IFE (Sebia).

Conclusion

The medical laboratories should be aware of the described scenario. The failure to detect light chains of certain intact M-proteins is most likely due to the structurally inaccessibility of light chains. It is recommended that treatment with reduction agents or use of an alternative methodology or IS might be helpful for investigating suspected heavy chain only cases, due to the limitation of conventional methodology.

Lubricin-Inspired Loop Zwitterionic Peptide for Fabrication of Superior Antifouling Surfaces

Biofouling represents great challenges in many applications, and zwitterionic peptides have been a promising candidate due to their biocompatibility and excellent antifouling performance. Inspired by lubricin, we designed a loop-like zwitterionic peptide and investigated the effect of conformation (linear or loop) on the antifouling properties using a combination of surface plasma resonance (SPR), surface force apparatus (SFA), and all atomistic molecular dynamics (MD) simulation techniques. Our results demonstrate that the loop-like zwitterionic peptides perform better in resisting the adsorption of proteins and bacteria. SFA measurements show that the loop-like peptides reduce the adhesion between the modified surface and the modeling foulant lysozyme. All atomistic MD simulations reveal that the loop-like zwitterionic peptides are more rigid than the linear-like zwitterionic peptides and avoid the penetration of the terminus into the foulants, which lower the interaction between the zwitterionic peptides and foulants. Besides, the loop-like zwitterionic peptides avoid the aggregation of the chains and bind more water, improving the hydrophilicity and antifouling performance. Altogether, this study provides a more comprehensive understanding of the conformation effect of zwitterionic peptides on their antifouling properties, which may contribute to designing novel antifouling materials in various biomedical applications.

[Identification and genetic analysis of new mutations in EYA1 gene of BOS syndrome]

Objective: To analyze the clinical manifestations of a patient with branchiootic syndrome(BOS) and her families and to carry out genetic testing in order to specify the biological pathogenesis. Methods: Clinical data of the patient and her families were collected. Genomic DNA in the peripheral blood of the proband and her family members was extracted. All exons of 406 deafness-related susceptible genes as well as their flanking regions were sequenced by high-throughput sequencing, and the mutation sites of the proband and her parents were validated by Sanger sequencing. Results: There were nine members in three generations, of whom four presented with hearing loss, preauricular fistula and branchial fistula which met the diagnostic criteria of BOS. Proband and her mother presented with auricle malformation and inner ear malformation. And no one had abnormalities in the kidneys of all the patients. Pedigree analysis revealed that the mode of inheritance in the family was consistent with the autosomal dominant pattern. Mutational analysis showed that all the affected patients detected a heterozygous frameshift variation c.1255delT in the EYA1 gene, which had not been reported. Genotype and phenotype were co-isolated in this family. Such a frameshift variation produced a premature termination codon, thereby causing premature termination of translation (p.C419VFS*12). ACMG identified that the mutation was pathogenic. This mutation was novel and not detected in controls. A heterozygous missense variation mutation c.403G>A(p.G135S) in EYA1 gene was also detected in three members of this family. ACMG identified that the mutation clinical significance was uncertain. However, two of whom were normal, which seemed the disease was not caused by this mutation in this family. Conclusions: A novel frameshift mutation in EYA1(c.1255delT) is the main molecular etiology of BOS in the Chinese family. This study expands the mutational spectrum of EYA1 gene. The clinical manifestations are heterogeneous among patients in this family. The diagnosis of BOS should combine gene tests with clinical phenotypes analysis.

Enhanced enzymatic hydrolysis of cellulose by endoglucanase via expansin pretreatment and the addition of zinc ions

One of the major limitations of lignocellulose conversion is the relatively low efficiency of cellulases. Expansins can act as an accessory protein to loosen the rigid cellulose structure and promote cellulose hydrolysis. However, the synergistic action of expansin is not well understood. In this study, we employed quartz crystal microbalance with dissipation to real-time monitor the adsorption of Bacillus subtilis expansin (BsEXLX1) and endoglucanase I (Cel7B) and the hydrolysis of cellulose. The effects of pH, temperature, and zinc ions on the initial adsorption rate and adsorption capacity of BsEXLX1 were examined. When 36.5 mM of zinc ions was added, the irreversible adsorption ratio of BsEXLX1 further increased to 4.63 times the value in the absence of zinc ions, whereas the initial adsorption rate and the hydrolysis rate constants of Cel7B could reach 2.16 times and 2.05 times the values in the absence of zinc ions, respectively.

Association between periodontal disease and prostate cancer: a systematic review and meta-analysis

Background

Periodontal disease is a chronic infectious disease caused by bacterial infection which may lead to various systematic diseases. Recently, increasing studies have explored the correlation of periodontal disease with the risk of prostate cancer. However, the findings were inconsistent. Hence, this study aims to investigate the association between periodontal disease and the risk of prostate cancer by a meta-analysis.

Material and Methods

PubMed, EMBASE, and Cochrane were searched for publications up to July 17, 2020. Cohort and case-control studies evaluating the risk of prostate cancer in patients with periodontal disease were included. A fixed or random-effect model was used to calculate the summary relative risk (RR) along with 95% confidence interval (CI). All analyses were conducted using Stata 12.0 software.

Results

Seven studies were included in the final analysis. The pooled estimates showed that periodontal disease was significantly associated with the risk of prostate cancer (RR = 1.17; 95% CI = 1.07-1.27; P = 0.001). Findings of sensitivity analyses proved that the overall results were robust.

Conclusions

Periodontal disease may be considered as a potential risk factor for prostate cancer. Although it’s a possibility, males should be more aware of their oral health and implement effective measures to prevent and treat periodontal disease.

Key words:Periodontal disease, periodontitis, prostate cancer, meta-analysis

[Effects and mechanisms of polycaprolactone-cellulose acetate nanofiber scaffold loaded with rat epidermal stem cells on wound healing of full-thickness skin defects in rats]

Objective: To explore the effects and mechanisms of polycaprolactone-cellulose acetate (PCL-CA) nanofiber scaffold loaded with rat epidermal stem cells (ESCs) on wound healing of full-thickness skin defects in rats. Methods: The experiment research method was applied. The primary ESCs were isolated from 1-3 d old Sprague-Dawley (SD) rats (undefined gender) by rapid adherent method and cultured by rapid adherent method. ESCs of the first passage were used for the subsequent experiments after the positive expressions of integrin β₁ and cytokeratin 19 (CK19) in primary cells were identified respectively by flow cytometey and immunofluorescence method. PCL-CA nanofiber scaffolds with polycaprolactone and cellulose acetate as components were prepared by electrospinning technique. The topological structure of the nanofiber scaffolds was determined and the diameter of 25 fibers was measured by scanning electron microscope. The constructed PCL-CA nanofiber scaffolds were used as the culture substrate for ESCs, which were cultured in keratinocytes (KCs) medium to construct ESCs-nanofiber scaffold complex (hereinafter referred to as ESCs scaffold). After 3 days of culture, the morphology of ESCs in the scaffold and their relationship was observed by scanning electron microscopy. The ESCs in ESCs scaffold were set as PCL-CA nanofiber scaffold group, and the ESCs cultured with KCs medium in culture dishes coated with type Ⅳ collagen were set as type Ⅳ collagen group. Western blotting was used to detect the protein expression level of CK19 in ESCs in the two groups after 3 days of culture (n=3). The protein expressions of CK19 and proliferating nuclear antigen (PCNA) in ESCs in the two groups were detected by immunofluorescence method after 7 days of culture. A circular full-thickness skin wound of about 2 cm in diameter was prepared on both left and right sides of the back of 15 male SD rats aged 6-8 weeks. The rats were then equally divided into blank control group without implantation, scaffold alone group implanted with PCL-CA nanofiber scaffold, and ESCs scaffold group implanted with ESCs scaffold which were constructed after 3 days of culture according to the random number table. The percentage of wound areas on post injury day (PID) 3, 7, 14, and 21 was calculated (n=5). The new skin tissue at the wound edge was collected on PID 21, the wound healing quality was evaluated by Masson staining, and the protein expression levels of Notch1, Jagged1, and Hes1, which are key proteins of Notch signaling pathway, were detected by Western blotting (n=3). Data were statistically analyzed with one-way analysis of variance, one-way analysis of variance, analysis of variance for repeated measurement, independent sample t test, and Bonferroni correction. Results: The constructed PCL-CA nanofiber scaffolds had a porous, mesh-like, and multilayered three-dimensional structure, in which the surface of the fibers was smooth and non-porous, and the fiber diameter was (383±24) nm. The ESCs in ESCs scaffold showed intact cellular structures and were tightly attached to the scaffold after 3 days of culture. The cells were interconnected and fully extended on the surface of the scaffold to form a membrane. After 3 days of culture, the protein expression level of CK19 of ESCs in PCL-CA nanofiber scaffold group was significantly higher than that in type Ⅳ collagen group (t=24.56, P<0.01). After 7 days of culture, compared with those in type Ⅳ collagen group, there was no significant change in the proportion of PCNA positive cells of ESCs in PCL-CA nanofiber scaffold group, while the proportion of CK19 positive cells was higher. On PID 3, 7, 14, and 21, the percentages of wound areas of rats in ESCs scaffold group were (78.0±1.8)%, (40.9±2.0)%, (17.9±1.1)%, and (5.0±1.0)%, respectively, which were significantly lower than (84.2±1.9)%, (45.4±2.6)%, (21.8±1.7)%, and (10.1±1.1)% in blank control group (t=5.42, 3.09, 4.33, 7.58, P<0.05 or P<0.01) and (82.7±1.2)%, (44.8±2.0)%, (22.4±2.4)%, and (10.3±2.4)% in scaffold alone group (t=4.98, 3.11, 3.84, 4.57, P<0.05 or P<0.01), while the percentages of wound areas of rats between blank control group and scaffold alone group were similar (t=1.47, 0.39, 0.47, 0.22, P>0.05). On PID 21, the layer of new skin at the wound edge of rats in each group was intact; compared with that in blank control group or scaffold alone group, the new skin tissue at the wound edge of rats in ESCs scaffold group had more orderly collagen arrangement; the scaffolds in the new skin at the wound edge of rats were completely degraded in ESCs scaffold group and scaffold alone group. On PID 21, the protein expression levels of Notch1, Jagged1, and Hes1 in the new skin tissue at the wound edge of rats in scaffold alone group were similar to those in blank control group (t=1.70, 1.94, 0.18, P>0.05), while the protein expression levels of Notch1, Jagged1, and Hes1 in the new skin tissue at the wound edge of rats in ESCs scaffold group were significantly higher than those in scaffold alone group (t=13.31, 22.07, 20.71, P<0.01). Conclusions: PCL-CA nanofiber scaffolds can inhibit the differentiation of ESCs of rats without affecting their proliferation in vitro. ESCs scaffolds constructed through using PCL-CA nanofiber scaffolds as the carrier to culture ESCs of rats can significantly promote the wound healing of full-thickness skin defects in rats, and the mechanism may be related to the activation of Notch signaling pathway.

[Aryl hydrocarbon receptor modulates airway inflammation in mice with cockroach allergen-induced asthma by regulating Th17/Treg differentiation]

OBJECTIVE

To investigate whether aryl hydrocarbon receptor (AhR) modulates cockroach allergen (CRE)-induced asthma by regulating Th17/Treg differentiation.

OBJECTIVE

Mouse models of CRE-induced asthma established by sensitizing and challenging the mice with CRE were randomized into asthma model group, AhR agonist group treated with TCDD (10 μg/ kg), and AhR antagonist group treated with TCDD and CH223191 (10 mg/kg) (n=5), with 5 mice without CRE challenge as the control group. The expressions of AhR, Cyp1a1 and Cyp1b1 mRNA in the lung tissues of the mice were detected using RT-PCR, and pulmonary inflammation was evaluated with immumohistochemical staining. The expressions of inflammatory cytokines in the lungs were detected using ELISA, and the expression of Treg in the lung tissues and pulmonary lymph nodes was analyzed with flow cytometry.

OBJECTIVE

Both TCDD and CH223191 were capable of modulating pulmonary expressions of AhR and its downstream genes Cyp1a1 and Cyp1b1 in asthmatic mice (P < 0.002). TCDD treatment significantly decreased inflammatory cells and mucus production in the lungs of asthmatic mice, and BALFs from TCDD-treated mice with CRE challenge contained lowered levels of the proinflammatory factors including IL-4, IL-13 and IL-17A (P < 0.001) but increased anti-inflammatory factors including IL-10, IL-22 and TGF-β1 (P < 0.001). All these changes were significantly reversed by treatment with CH223191 to the levels comparable with those in the asthma model group (P>0.05). More importantly, TCDD treatment significantly increased the number of Tregs cells and FOXP3 expression and lowered RORγt mRNA expression in the lungs and pulmonary lymph nodes in asthmatic mice (P < 0.001); inhibition of AhR with CH223191, as compared with TCDD, significantly decreased the expression of CD4⁺CD25⁺Foxp3⁺Treg cells in the lungs and pulmonary lymph nodes and the expression of FOXP3 mRNA in lymphocytes and increased RORγt mRNA expression (P < 0.001) to the levels comparable with those in asthma model group (P>0.05).

OBJECTIVE

AhR activation modulates airway inflammation in mice with CRE-induced asthma by modulating the differentiation of Th17/Treg.

New Limit for Neutrinoless Double-Beta Decay of ^{100}Mo from the CUPID-Mo Experiment

The CUPID-Mo experiment at the Laboratoire Souterrain de Modane (France) is a demonstrator for CUPID, the next-generation ton-scale bolometric 0νββ experiment. It consists of a 4.2 kg array of 20 enriched Li_{2}^{100}MoO_{4} scintillating bolometers to search for the lepton-number-violating process of 0νββ decay in ^{100}Mo. With more than one year of operation (^{100}Mo exposure of 1.17  kg×yr for physics data), no event in the region of interest and, hence, no evidence for 0νββ is observed. We report a new limit on the half-life of 0νββ decay in ^{100}Mo of T_{1/2}>1.5×10^{24}  yr at 90% C.I. The limit corresponds to an effective Majorana neutrino mass ⟨m_{ββ}⟩<(0.31-0.54)  eV, dependent on the nuclear matrix element in the light Majorana neutrino exchange interpretation.

Synergistic effect of polystyrene nanoplastics and contaminants on the promotion of insulin fibrillation

Nanoplastics (NPs) are becoming an emerging pollutant of global concern. A potential risk of NPs is that they can serve as carriers and synergistically function with other contaminants to cause diseases. A variety of diseases such as Alzheimer's disease are related to the generation of amyloid fibrils, and insulin is typically used as a model to study the fibrillation process. In this study, we examined the fibrillation of insulin promoted by polystyrene nanoplastics (PSNPs) alone and synergistically with organic contaminants (denoted as X, X = pyrene, bisphenol A, 2,2',4,4'-tetrabromodiphenyl ether, 4,4'-dihydroxydiphenylmethane, or 4-nonylphenol) having different polarities using thioflavin T fluorescence assays, dynamic light scattering, and circular dichroism spectroscopy. The presence of PSNPs and small organic contaminants decreased the lag phase time (t_lag) for insulin fibrillation from 54.6 h to 35-51 h and their combination (PS-X) enhanced this process (t_lag = 21-30 h). Notably, the lag phase time for insulin fibrillation with PS-nonpolar contaminants, PS-weakly polar contaminants, and PS-polar contaminants is around 20.8, 26.7, and 30.1 h, respectively, indicating the synergistic effect of PS-nonpolar contaminants or PS-weakly polar contaminants was more obvious than that of PS-polar contaminants. Moreover, molecular dynamic simulation reveal the interactions between insulin and PSs or small organic contaminants are primarily driven by van der Waals forces and hydrophobic interactions. Overall, the findings of this study underscore the potentially significant environmental impact of small organic contaminants assisting NPs in promoting insulin fibrillation.

Biomimetic surface coatings for marine antifouling: Natural antifoulants, synthetic polymers and surface microtopography

Marine biofouling is a ubiquitous problem that accompanies human marine activities and marine industries. It exerts detrimental impacts on the economy, environment, ecology, and safety. Traditionally, mainstream approaches utilize metal ions to prevent biological contamination, but this also leads to environmental pollution and damage to the ecosystem. Efficient and environmentally friendly coatings are urgently needed to prevent marine devices from biofouling. Since nature is always the best teacher for humans, it offers us delightful thoughts on the research and development of high-efficiency, broad-spectrum and eco-friendly antifouling coatings. In this work, we focus on the research frontier of marine antifouling coatings from a bionic perspective. Enlightened by three distinctive dimensions of bionics: chemical molecule bionic, physiological mechanism bionic, and physical structure bionic, the research status of three main bioinspired strategies, which are natural antifoulants, bioinspired polymeric antifouling coatings, and biomimetic surface microtopographies, respectively, are demonstrated. The antifouling mechanisms are further interpreted based on biomimetic comprehension. The main fabrication methods and antifouling performances of these coatings are presented along with their advantages and drawbacks. Finally, the challenges are summarized, and future research prospects are proposed. It is believed that biomimetic antifouling strategies will contribute to the development of nontoxic antifouling techniques with exceptional repellency and stability.

Metabolic syndrome cannot mask the changes of faecal microbiota compositions caused by primary hepatocellular carcinoma

Both hepatocellular carcinoma (HCC) and metabolic syndrome are closely associated with the composition of the gut microbiota (GM). Although it has been proposed that elements of the GM can be used as biomarkers for the early diagnosis of HCC, whether metabolic syndrome results in a misrepresentation of the results of the early diagnosis of HCC using GM remains unclear. We compared the differences in the faecal microbiota of 10 patients with primary HCC, six patients with type 2 diabetes mellitus (T2DM), seven patients with arterial hypertension, six patients with both HCC and T2DM, and 10 patients with both HCC and arterial hypertension, as well as 10 healthy subjects, using high-throughput sequencing of 16S rRNA gene amplicons. Our results revealed a significant difference in the GM between subjects with and without HCC. The 49 bacterial genera out of the 494 detected genera were significantly different between the groups. These results show that changes in the GM can be used to distinguish between subjects with and without HCC, and can resist interference of T2DM and arterial hypertension with the GM. The results of the present study provide an important basis for the clinical auxiliary diagnosis of HCC by detecting the GM.

A205 PEMBROLIZUMAB ASSOCIATED SCLEROSING CHOLANGITIS RESPONDS TO COMBINATION OF STEROIDS AND MYCOPHENOLIC ACID: A CASE REPORT

Background

Pembrolizumab is a check point inhibitor that targets programmed cell death receptor ligand 1 (PD-L1). However, check-point inhibitors are associated with its characteristic adverse event know as immune related adverse events that can affect a myriad of organ systems. In the hepatobiliary system, the most commonly described iRAE is hepatitis/hepatotoxicity and latest oncology guidelines offer recommendations on treatment and followup of immunotherapy related hepatitis (1). However, a more rare presentation of iRAE, that have only been described as case reports or case series, is secondary cholangitis. We report one of such a case.

Aims

Case report

Methods

Case report

Results

The patient is a 55 year-old Caucasian female know for lung adenocarcinoma presented to the emergency room on May 5th, 2020, having received her 8th cycle of pembrolizumab. Her blood works mildly elevated transaminitis; ALT 78 U/L, AST 11 U/L, alkaline phosphate of 130 U/L, and total bilirubin of 3.5 umol/L.

MRI of the abdomen showed a normal appearing liver without focal parenchymal lesion, no biliary stones or obstructing masses, dilated common bile duct at 11 mm with small pericholecystic free fluid, and normal gall badder thickness of 2 mm. There was also notion of minimally prominent intrahepatic biliary radicles seen within the CBD.

Etiology workup of cholestatic transaminitis was negative. A diagnosis of immunotherapy related sclerosing cholangitis was posed and the patient was treated with MMF and prednisone with good response.

Conclusions

Discussion

This patient seems to have developed immunotherapy mediated cholangitis. Liver biopsy when performed in liver injury tend to show lobular hepatitis, with liver parenchyma infiltrated with lymphocytes and focal necrosis with acidophilic bodies. However, there seems to be another, less frequent pattern of injury described with pembrolizumab and associated with cholangiopathy, resembling primary biliary cholangitis. It is characterized with portal tracts enlarged with fibrosis and inflammatory cells infiltration; infiltrating cells are lymphocytes (2). Biliary epithelium with fibrosis with CD8+ T cells infiltration seem to be recurrently reported in case reports. (3, 4).

Other cases have been describe in the literature. In many cases, steroid therapy was attempted, but response rates seem to be inconsistent. Nivolumab related cholangitis have been also been described and characterized by extra hepatic bile duct dilatation along with negative immunological markers such as ANA and IgG4 in patients with non-small cell lung cancer, and seems to respond only moderately to steroid therapy (6). Retrospective data of nivolumab related cholangiopathy seems to suggest that there is favourable response to the combination of MMF and steroid therapy (7).

Funding Agencies

None

Utility of Contrast-Enhanced T2 FLAIR for Imaging Brain Metastases Using a Half-dose High-Relaxivity Contrast Agent

BACKGROUND AND PURPOSE

Efficient detection of metastases is important for patient' treatment. This prospective study was to explore the clinical value of contrast-enhanced T2 FLAIR in imaging brain metastases using half-dose gadobenate dimeglumine.

MATERIALS AND METHODS

In vitro signal intensity of various gadolinium concentrations was explored by spin-echo T1-weighted imaging and T2 FLAIR. Then, 46 patients with lung cancer underwent nonenhanced T2 FLAIR before administration of half-dose gadobenate dimeglumine and 3 consecutive contrast-enhanced T2 FLAIR sequences followed by 1 spin-echo T1WI after administration of half-dose gadobenate dimeglumine. After an additional dose of 0.05 mmol/kg, 3D brain volume imaging was performed. All brain metastases were classified as follows: solid-enhancing, ≥ 5 mm (group A); ring-enhancing, ≥ 5 mm (group B); and lesion diameter of <5 mm (group C). The contrast ratio of the lesions on 3 consecutive phases of contrast-enhanced T2 FLAIR was measured, and the percentage increase of contrast-enhanced T2 FLAIR among the 3 groups was compared.

RESULTS

In vitro, the maximal signal intensity was achieved in T2 FLAIR at one-eighth to one-half of the contrast concentration needed for maximal signal intensity in T1WI. In vivo, the mean contrast ratio values of metastases on contrast-enhanced T2 FLAIR for the 3 consecutive phases ranged from 63.64% to 83.05%. The percentage increase (PI) values of contrast-enhanced T2 FLAIR were as follows: PI_A < PI_B (P = .001) and PI_A < PI_C (P < .001). The degree of enhancement of brain metastases on contrast-enhanced T2 FLAIR was lower than on 3D brain volume imaging (P < .001) in group A, and higher than on 3D brain volume imaging (P < .001) in group C.

CONCLUSIONS

Small or ring-enhancing metastases can be better visualized on delayed contrast-enhanced T2 FLAIR using a half-dose high-relaxivity contrast agent.

Spinal schwannoma causes acute subarachnoid haemorrhage: A case report and literature review

BACKGROUND

Spinal schwannomas that arise from spinal nerve root sheaths are the most common intradural extramedullary spinal tumours and are often accompanied by nerve roots or spinal cord irritation symptoms. The phenomenon of spinal schwannoma causing subarachnoid haemorrhage (SAH) is rare, with ependymoma of the conus medullaris accounting for most cases.

CASE REPORT

A 45-year-old man was admitted to our hospital due to progressive lower limb weakness and sudden back pain after hard physical work. The patient had not been able to walk for 2hours upon admission. An emergency magnetic resonance imaging (MRI) scan showed that the spinal cord at the C6-T4 level was severely compressed by a subdural mass. During the emergency operation, exploration of the dura and arachnoid mater revealed a fresh blood clot covering a tumour located on the ventral side of the spinal cord. The size of the tumour was approximately 3×2×1cm without adhesion to the surrounding tissue, but the drainage vein was ruptured. Postoperative pathology showed that the tumour was a schwannoma with areas of fresh haemorrhage and focal necrosis.

CONCLUSIONS

Spinal schwannomas presenting with SAH are rare events. In our opinion, spinal pathology with rapid progression of neurological symptoms requires early diagnosis and emergency management. Complete excision of haemorrhagic tumours is the goal of treatment to prevent recurrence, which can effectively avoid irreversible damage to the spinal cord resulting from spinal cord compression.

Preparation of laccase mimicking nanozymes and their catalytic oxidation of phenolic pollutants

The construction of a nanozyme that mimics a natural enzyme is a promising strategy to obtain a highly stable catalyst.

[Research frontiers in precision therapy for liver cancer]

Hepatocellular carcinoma (HCC), a fatal malignancy, is highly prevalent in China. Recently, tremendous achievements have been made in HCC, both in the clinical management and the understanding of cancer biology. The discovery and application of novel serum biomarkers, such as proteins, miRNAs, and cfDNA (cell-free circulating DNA) methylation will facilitate the early management of HCC. Improvements in radiological and computational technology have made the practice of precision liver surgery a true reality. The emergence of novel molecular targeted therapies, immunotherapy and their combinations has significantly prolonged patient survival rate, but the therapeutic breakthroughs are still needed. Integrated multi-omics analysis has broadened our understanding of HCC pathogenesis, providing an unprecedented molecular characterization of HCC and revealing new therapeutic opportunities. Technological innovations and revolutions such as single-cell sequencing, genome editing, and innovative drug research and development will greatly accelerate our understanding of HCC biology and bring new therapeutic opportunities. Nevertheless, HCC is a highly heterogeneous and treatment-refractory malignancy, therefore deep insights into the biology of the disease and novel therapies for HCC remain an unmet medical need.