[Preparation and preliminary application of the polyclonal antibody against Toxoplasma gondii dense granule protein 24]

OBJECTIVE

To prepare and characterize the mouse polyclonal antibody against the dense granule protein 24 (GRA24) of Toxoplasma gondii, and explore its preliminary applications.

METHODS

The GRA24 coding sequences of different T. gondii strains were aligned using the MEGA-X software, and the dominant peptide of the GRA24 protein was analyzed with the Protean software. The base sequence encoding this peptide was amplified using PCR assay and ligated into the pET-28a vector, and the generated GRA24 truncated protein was transformed into Escherichia coli BL21. After induction by isopropyl-beta-D-thiogalactopyranoside (IPTG), the expression and purification of the recombinant GRA24 protein was analyzed using sodium dodecyl sulfate - polyacrylamide gel electrophoresis (SDS-PAGE). BALB/c mice were immunized by subcutaneous injection with the purified recombinant GRA24 truncated protein to generate the polyclonal antibody, and the titer of the polyclonal antibody was measured using enzyme linked immunosorbent assay (ELISA). The specificity of the polyclonal antibody was tested using Western blotting, and the intracellular localization of the polyclonal antibody was investigated using immunofluorescence assay (IFA).

RESULTS

SDS-PAGE showed successful construction of the recombinant expression plasmid, and Coomassie brilliant blue staining showed the generation of the high-purity recombinant GRA24 truncated protein. ELISA measured that the titer of the polyclonal antibody against the GRA24 truncated protein was higher than 1:208 400, and Western blotting showed that the polyclonal antibody was effective to recognize the endogenous GRA24 proteins of different T. gondii strains and specifically recognize the recombinant GRA24 truncated protein. Indirect IFA showed that the GRA24 protein secreted 16 hour following T. gondii invasion in host cells.

CONCLUSIONS

The polyclonal antibody against the T. gondii GRA24 protein has been successfully prepared, which has a widespread applicability, high titers and a high specificity. This polyclonal antibody is available for Western blotting and IFA, which provides the basis for investigating the function of the GRA24 protein.

Diagnostic value of serum squamous cell carcinoma antigen and cytokeratin fragment antigen 21-1 for sinonasal inverted papilloma: an exploratory study

BACKGROUND

Serum tumor markers have not yet been developed for the clinical diagnosis and treatment of sinonasal inverted papilloma (SNIP), one of the most significant sinonasal tumors. Therefore, this study aimed to determine the diagnostic value of serum squamous cell carcinoma antigen (SCCA) and cytokeratin fragment antigen 21-1 (CYFRA 21-1) for SNIP.

METHODS

Clinical data were obtained from 101, 56, and 116 patients with SNIP, sinonasal squamous cell carcinoma (SNSCC), and unilateral chronic rhinosinusitis (CRS), respectively. Preoperative serum SCCA and CYFRA 21-1 levels were compared, and logistic regression analyses were performed to screen serum tumor markers, which may be used to diagnose SNIP. Diagnostic cut-off values were determined using receiver operating characteristic (ROC) curves, and their diagnostic power was verified.

RESULTS

Serum SCCA and CYFRA 21-1 differentiated SNIP from CRS with the cut-off values of 1.97 ng/mL and 2.64 ng/mL and the areas under the ROC curves (AUC) of 0.895 and 0.766, respectively, and the AUC of the combination of the two markers was 0.909. CYFRA 21-1 differentiated SNIP with malignant transformation from that without malignant transformation with a cut-off value of 3.51 ng/mL and an AUC of 0.938. CYFRA 21-1 distinguished SNIP with malignant transformation from SNSCC with a cut-off value of 3.55 ng/mL and an AUC of 0.767.

CONCLUSIONS

This study provides novel potential diagnostic tools for SNIP by demonstrating the use of serum SCCA and CYFRA 21-1 in the diagnosis of SNIP.

[Changes of hemodynamic parameters in normal pregnant women and their relationship with maternal basic characteristics]

Objective: To investigate the variation of reference ranges of hemodynamic parameters in normal pregnancy and their relation to maternal basic characteristics. Methods: A total of 598 healthy pregnant women who underwent regular prenatal examination at the Third Affiliated Hospital of Guangzhou Medical University from January to December 2023 were prospectively enrolled, and noninvasive hemodynamic monitors were used to detect changes in hemodynamic parameters of the pregnant women with the week of gestation, including cardiac output (CO), stroke volume (SV), thoracic fluid content (TFC), systemic vascular resistance (SVR), mean arterial pressure (MAP), and heart rate (HR). Relationships between hemodynamic parameters and maternal basic characteristics, including age, height, and weight, were analyzed using restricted cubic spline. Results: (1) CO (r=0.155, P<0.001), TFC (r=0.338, P<0.001), MAP (r=0.204, P<0.001), and HR (r=0.352, P<0.001) were positively correlated with the week of gestation, and SV was negatively correlated with the week of gestation (r=-0.158, P<0.001). There was no significant correlation between SVR and gestational age (r=-0.051, P=0.258). (2) CO exhibited a positive correlation with maternal height and weight (all P<0.001). The taller and heavier of pregnant women, the higher their CO. A linear relationship was observed between maternal weight and SV, MAP and HR (all P<0.01). As maternal weight increased, SV, MAP and HR showed an upward trend. Furthermore, there was an inverse association between maternal age and SVR (P<0.001). (3) There was a significant nonlinear association observed between TFC and body mass index during pregnancy (P<0.05). Additionally, a nonlinear relationship was found between SVR and MAP in relation to maternal age (all P<0.05). Notably, when the age exceeded 31 years old, there was an evident upward trend observed in both SVR and MAP. Conclusions: The hemodynamic parameters of normal pregnant women are influenced by their height, body weight, and age. It is advisable to maintain a reasonable weight during pregnancy and give birth at an appropriate age.

The differences between sinonasal respiratory epithelial adenomatoid hamartoma and nasal polyps: insights into immunopathology

BACKGROUND

Respiratory epithelial adenomatoid hamartoma (REAH) is a benign lesion commonly occurring in the nasal cavity and sinuses. It is often accompanied by nasal polyps (NP). While the histological features of these two conditions have been studied, there is limited knowledge about their differences in the underlying immunopathology.

METHODS

Nasal tissue specimens were collected from 8 patients with concurrent REAH and NP and 10 controls. The expression levels of inflammatory cytokines, tight junctions (TJ), and epithelial-mesenchymal transition (EMT)-related factors in the tissues were analyzed. The mRNA expression of the aforementioned factors was measured using qRT-PCR, while the expression of TJ and EMT-related proteins was analyzed through Western blotting and immunohistochemistry.

RESULTS

Compared to the control group, levels of inflammatory cytokines (IFN-γ, IL-5, IL-17A, IL-31, IL-33, and TNF-α) and EMT-related factors (α-SMA, COL1A1, MMP9, TGF-β1, and Vimentin) were significantly increased in both REAH and NP tissues. Conversely, E-Cadherin and TJ-related factors (Claudin-4 and Occludin) significantly decreased. When comparing REAH with NP, it was observed that the expression of IL-4, IL-5, and IL-33 was lower in REAH, while TNF-α was higher. Regarding TJ-related factors, the expression of Occludin was lower in REAH. Furthermore, in terms of EMT-related factors, except for E-Cadherin, the expressions of α-SMA, COL1A1, CTGF, MMP9, TGF-β1, and Vimentin were higher in REAH.

CONCLUSION

REAH and NP exhibit different immunopathological mechanisms. NP demonstrates a more severe inflammatory response, whereas REAH is characterized by a more pronounced TJ and EMT breakdown than NP.

Urinary Catheters: Materials, Coatings, and Recommendations for Selection

Urinary catheters have been used for more than 3000 years, although materials have changed from wood to silver to rubber. Research continues to try and find the optimal catheter materials, which improve safety and quality of life. Advantages when comparing newer catheter materials are not always obvious but catheters coated with a hydrophilic layer may reduce urethral trauma and the incidence of urinary tract infections. However, extrapolation of the data is limited by lack of end-point standardization and heterogenous populations.

Clinical practice guideline-inconsistent management of fever and neutropenia in pediatric oncology: A Children's Oncology Group study

BACKGROUND

The primary objective was to measure the proportion of episodes where care delivery was inconsistent with selected recommendations of a clinical practice guideline (CPG) on fever and neutropenia (FN) management. The influence of site size on CPG-inconsistent care delivery, and association between patient outcomes and CPG-inconsistent care were described.

METHODS

This retrospective, multicenter study included patients less than 21 years old with cancer who were at high risk of poor FN outcomes and were previously enrolled to a Children's Oncology Group (COG) study at participating National Cancer Institute Community Oncology Research Program (NCORP) institutions from January 2014 through December 2015. Patients were randomly selected for chart review by participating sites from a COG-generated list. Care delivered in each episode was adjudicated (CPG-consistent or CPG-inconsistent) against each of five selected recommendations.

RESULTS

A total of 107 patients from 22 sites, representing 157 FN episodes, were included. The most common CPG-inconsistent care delivered was omission of pulmonary computerized tomography in patients with persistent FN (60.3%). Of 74 episodes where assessment of four (episodes without persistent FN) or five (episodes with persistent FN) recommendations was possible, CPG-inconsistent care was delivered with respect to at least one recommendation in 63 (85%) episodes. Site size was not associated with CPG-inconsistent care delivery. No statistically significant association between CPG-inconsistent care and fever recurrence was observed.

CONCLUSIONS

In this cohort of pediatric patients at high risk of poor FN outcomes, CPG-inconsistent care was common. Opportunities to optimize resource stewardship by boosting supportive care CPG implementation are highlighted.

[Characteristics and changes of cardiac injury with age in children of Duchenne muscular dystrophy: a prospective cohort study]

Objective: To explore the characteristics and changes of cardiac injury with age in Duchenne muscular dystrophy (DMD) and its clinical significance. Methods: A prospective cohort study was conducted. The 215 patients diagnosed with DMD in West China Second Hospital from January 2019 to November 2022 and aged from 6 to 18 years were enrolled. Their clinical data, myocardial injury markers, routine electrocardiogram, cardiac magnetic resonance (CMR) and echocardiography were collected. The patients were divided into five age groups: 6-<8, 8-<10, 10-<12, 12-<14 and 14-18 years of age, and matched with healthy boys respectively. Independent sample t test or Mann-Whitney U test was used to compare the clinical data and CMR indexes between DMD patients and controls in all age subgroups, and to compare the value of left ventricular ejection fraction (LVEF) measured by echocardiography and CMR in each subgroup of DMD patitents. Pearson correlation analysis or Spearman correlation analysis was used to explore the relation between the CMR indexes and age in DMD patients. Results: A total of 215 patients with DMD (all male) and 122 healthy boys were included in the study. There were 75 DMD patients and 23 controls in 6-<8 years of age group, 77 DMD and 28 controls in 8-<10 years of age group, 39 DMD and 23 controls in 10-<12 years of age group, 10 DMD and 31 controls in the 12-<14 years of age group, and 14 DMD and 17 controls in 14-18 years of age group. In the DMD patients, the older the age, the lower the levels of creatine kinase (CK) and creatine kinase isoenzyme (CK-MB). In the 6-<8 years of age group, the CK level was 10 760 (7 800, 15 757) U/L, while in the group of 14-18 years of age, it was 2 369 (1 480, 6 944) U/L. As for CK-MB, it was (189±17) μg/L in the 6-<8 years of age group and (62±16) μg/L in the 14-18 years of age group. Cardiac troponin I remained unchanged in <12 years of age groups, but significantly increased in 12-<14 years of age group, reaching the highest value of 0.112 (0.006, 0.085) μg/L. In the DMD patients, the older the age, the higher the proportion of abnormal electrocardiogram (ECG). In the 6-<8 years of age group, the proportion is 29.3% (22/75), while in the 14-18 years of age group, it was 10/14. Correlation analysis showed that the left ventricular end-diastolic volume index was positively related with age (r=0.18, P=0.015), and the left ventricular stroke volume index and cardiac output index were negatively related with age (r=-0.34 and -0.31, respectively, both P<0.001). In the DMD patients, the older the age, the lower LVEF, with the LVEF decreasing to (49.3±3.1)% in the 14-18 years of age group. The LVEF of DMD cases was significantly lower than that of controls in the age subgroups of 8-<10, 10-<12, 12-<14 and 14-18 years of age groups ((57.9±5.2) % vs. (63.6±0.8)%, 60.7% (55.9%, 61.9%) vs. 63.7% (60.2%, 66.0%), 57.1% (51.8%, 63.4%) vs. 62.1 % (59.5%, 64.5)%, (49.3±3.1) % vs. (61.6±1.3)%, respectively; all P<0.01). In the DMD patients, the older the age, the higher the proportion of positive late gadolinium enhancement (LGE). In the 6-<8 years of age group, it was 22% (11/51), in the 12-<14 years of age group, it was 13/14, and in the 14-18 years of age group, all DMD showed positive LGE. The value of LVEF of DMD cases measured by echocardiography was significantly higher than that measured by CMR in 6-<8 years of age group and 8-<10 years of age group (63.2% (60.1%, 66.4%) vs. 59.1 % (55.4%, 62.9%), and (62.8±5.2) % vs. (57.9±5.2)%, all P<0.001). Conclusion: DMD patients develop cardiac injury in the early stage of the disease, and the incidence of cardiac damage gradually increases with both age and the progression of disease.

Genetic determinants of micronucleus formation in vivo

Genomic instability arising from defective responses to DNA damage1 or mitotic chromosomal imbalances2 can lead to the sequestration of DNA in aberrant extranuclear structures called micronuclei (MN). Although MN are a hallmark of ageing and diseases associated with genomic instability, the catalogue of genetic players that regulate the generation of MN remains to be determined. Here we analyse 997 mouse mutant lines, revealing 145 genes whose loss significantly increases (n = 71) or decreases (n = 74) MN formation, including many genes whose orthologues are linked to human disease. We found that mice null for Dscc1, which showed the most significant increase in MN, also displayed a range of phenotypes characteristic of patients with cohesinopathy disorders. After validating the DSCC1-associated MN instability phenotype in human cells, we used genome-wide CRISPR-Cas9 screening to define synthetic lethal and synthetic rescue interactors. We found that the loss of SIRT1 can rescue phenotypes associated with DSCC1 loss in a manner paralleling restoration of protein acetylation of SMC3. Our study reveals factors involved in maintaining genomic stability and shows how this information can be used to identify mechanisms that are relevant to human disease biology1.

Novel Psilocin Prodrugs with Altered Pharmacological Properties as Candidate Therapies for Treatment-Resistant Anxiety Disorders

The psychedelic prodrug psilocybin has shown therapeutic benefits for the treatment of numerous psychiatric conditions. Despite positive clinical end points targeting depression and anxiety, concerns regarding the duration of the psychedelic experience produced by psilocybin, associated with enduring systemic exposure to the active metabolite psilocin, pose a barrier to its therapeutic application. Our objective was to create a novel prodrug of psilocin with similar therapeutic benefits but a reduced duration of psychedelic effects compared with psilocybin. Here, we report the synthesis and functional screening of 28 new chemical entities. Our strategy was to introduce a diversity of cleavable groups at the 4-hydroxy position of the core indole moiety to modulate metabolic processing. We identified several novel prodrugs of psilocin with altered pharmacokinetic profiles and reduced pharmacological exposure compared with psilocybin. These candidate prodrugs have the potential to maintain the long-term benefits of psilocybin therapy while attenuating the duration of psychedelic effects.

[Advances in research on the role of immune cells in optic nerve injury]

Optic nerve injury can result in the loss of retinal ganglion cells (RGCs) and their axons, representing a significant cause of irreversible vision impairment. Immune response is a common step following injury, and it often exhibits contrasting effects in optic nerve pathologies. Immune cells play a crucial role in this process, and understanding the differentiation of various immune cells post-injury, mitigating their neurotoxicity, and directing them towards a beneficial outcome for the protection of RGCs and axons are vital for optic nerve preservation. This paper provides a comprehensive review of the research progress on immune cells such as macrophages, microglia, T cells, and others in the field of optic nerve injury. Additionally, discussions include the identification of cell phenotypes and the exploration of the novel concept of innate immunity possibly possessing memory.

[SRF-rearranged cellular perivascular myoid tumor: a clinicopathological analysis of two cases]

Objective: To investigate the clinicopathological features, immunophenotype, diagnosis and differential diagnosis of SRF-rearranged cellular perivascular myoid tumor. Methods: Two cases of SRF-rearranged cellular perivascular myoid tumor diagnosed in the Department of Pathology, Fudan University Shanghai Cancer Center from October 2021 to March 2022 were collected. Immunohistochemical staining, fluorescence in-situ hybridization (FISH) and next-generation sequencing (NGS) were performed, and the literature was reviewed. Results: Case 1, a 3-month-old boy presented with a painless tumor of the scalp, measuring about 2 cm in diameter. Case 2, a 3-year-old girl complained with a painless tumor of the knee, measuring approximately 1.5 cm in diameter. Microscopically, the tumor had a clear boundary and showed multinodular growth. The tumor was mainly composed of spindle cells arranged in long intersecting fascicles associated with thin, slit-like or branching ectatic vessels, focally forming hemangiopericytoma-like appearance. The tumor cells were abundant, but there was no obvious atypia. Mitotic figures (3-4/10 HPF) were noted. H-caldesmon and SMA were positive in both cases. Case 1 showed diffuse and strong positivity for Desmin, and focally for CKpan. Ki-67 proliferation index was 20% and 30%, respectively. FISH displayed NCOA2 gene translocation in case 1 and the RELA gene translocation in case 2. NGS detected the SRF-NCOA2 gene fusion in case 1 and the SRF-RELA gene fusion in case 2. Both patients underwent local excisions. During the follow-up of 5-14 months, case 1 had no local recurrence, while case 2 developed local recurrence 1 year post operatively. Conclusions: SRF-rearranged cellular perivascular myoid tumor is a novel variant of perivascular cell tumor, which tends to occur in children and adolescents. The tumor forms a broad morphologic spectrum ranging from a pericytic pattern to a myoid pattern, and include hybrid tumors with a mixture of pericytic and myoid patterns. Due to its diffuse hypercellularity and increased mitotic figures and smooth muscle-like immunophenotype, the tumor is easy to be misdiagnosed as myogenic sarcomas. The tumor usually pursues a benign clinical course and rare cases may locally recur.

Investigating the Impact of Tea Consumption on Cognitive Function and Exploring Tea-Genetic Interactions in Older Adults Aged 65-105 Years: Findings from the 2002-2018 CLHLS Data

BACKGROUND

As the global population ages, cognitive impairment (CI) becomes more prevalent. Tea has been one of the most popular drinks in the world. Several studies have demonstrated that tea consumption has an impact on cognitive function.

OBJECTIVE

This study aims to examine the association between tea consumption and cognitive function and explore the potential effect of genetics on the relationship between tea consumption and CI risk in older adults.

DESIGN

This is a prospective longitudinal study using data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS).

SETTING

Six waves of data from CLHLS containing 76,270 subjects were analyzed. Generalized estimation equations (GEE) with a logit link function were adopted to estimate the effect of tea consumption on CI risk from a cross-sectional and longitudinal perspective.

PARTICIPANTS

A population-based cohort of adults aged 65-105 years.

MEASUREMENTS

The frequency and type of tea consumption were obtained by questionnaires. CI was measured based on MMSE. Polygenic risk was measured using the polygenic score approach described by the International Schizophrenia.

RESULTS

The results showed that drinking green tea had a better protective effect on cognitive function than other types of tea, the incidence of CI gradually decreased with the increase of tea consumption frequency, and men were more likely to benefit from tea consumption. Additionally, we also found a significant interaction between tea consumption and genetic risk, measured by polygenic risk score (PRS).

CONCLUSIONS

Based on current research evidence, tea consumption, may be a simple and important measure for CI prevention.

Long 3'UTRs predispose neurons to inflammation by promoting immunostimulatory double-stranded RNA formation

Loss of RNA homeostasis underlies numerous neurodegenerative and neuroinflammatory diseases. However, the molecular mechanisms that trigger neuroinflammation are poorly understood. Viral double-stranded RNA (dsRNA) triggers innate immune responses when sensed by host pattern recognition receptors (PRRs) present in all cell types. Here, we report that human neurons intrinsically carry exceptionally high levels of immunostimulatory dsRNAs and identify long 3'UTRs as giving rise to neuronal dsRNA structures. We found that the neuron-enriched ELAVL family of genes (ELAVL2, ELAVL3, and ELAVL4) can increase (i) 3'UTR length, (ii) dsRNA load, and (iii) activation of dsRNA-sensing PRRs such as MDA5, PKR, and TLR3. In wild-type neurons, neuronal dsRNAs signaled through PRRs to induce tonic production of the antiviral type I interferon. Depleting ELAVL2 in WT neurons led to global shortening of 3'UTR length, reduced immunostimulatory dsRNA levels, and rendered WT neurons susceptible to herpes simplex virus and Zika virus infection. Neurons deficient in ADAR1, a dsRNA-editing enzyme mutated in the neuroinflammatory disorder Aicardi-Goutières syndrome, exhibited intolerably high levels of dsRNA that triggered PRR-mediated toxic inflammation and neuronal death. Depleting ELAVL2 in ADAR1 knockout neurons led to prolonged neuron survival by reducing immunostimulatory dsRNA levels. In summary, neurons are specialized cells where PRRs constantly sense "self" dsRNAs to preemptively induce protective antiviral immunity, but maintaining RNA homeostasis is paramount to prevent pathological neuroinflammation.

[Esophageal dysmotility detection in patients with gastroesophageal reflux-related cough and its influence on the efficacy of anti-reflux therapy]

Objective: To investigate the characteristics of esophageal dysmotility in patients with an initial diagnosis of acid/non-acid gastroesophageal reflux-related cough (GERC), and its correlation with the therapeutic response to anti-reflux treatments to search for the useful indicators to screen patients with chronic cough suitable for anti-reflux therapy. Methods: A total of 173 patients with suspicious GERC who attended the Chronic Cough Specialist Clinic of Department of Pulmonary and Critical Care Medicine, Tongji Hospital, School of Medicine, Tongji University between June 2020 and December 2022 were retrospectively selected for the study. The age of the patients was (45.1±14.6) years old, including 87 males and 86 females. Their demographic characteristics, clinical manifestations, and the results of high-resolution manometry (HRM) and multichannel intraluminal impedance-pH monitoring (MII-pH) were collected. Information on the etiological identification process and final diagnosis was also recorded. The recruited cases were grouped according to therapeutic outcomes and divided into cases with a favourable response to conventional anti-reflux treatment, cases with a favourable response to intensified anti-reflux treatment, and cases with no response to anti-reflux treatment. Factors influencing the efficacy of anti-reflux treatment were investigated. Differences between groups were compared using the χ2 test, Student-Newman-Keuls test, and Kruskal-Wallis H(K) test, where applicable. Logistic regression analysis using forward stepwise regression based on maximum likelihood estimation was used to screen for influence factors. Results: The 175 patients with suspicious GERC included 45 (26.0%) patients who responded to conventional anti-reflux treatment, 54 (31.2%) who responded to intensified anti-reflux treatment and 74 (42.8%) who did not respond to anti-reflux therapies. Esophageal dysmotility was present in 52.0% of patients (90/173), but was less common in patients who responded to conventional anti-reflux treatment (χ2=8.09, P=0.018). Although the majority of reflux episodes were non-acid (136/173, 78.6%), the proportion of acid reflux (χ2=19.49, P<0.001) and acid exposure time (H=11.04, P=0.004) were significantly higher in patients who responded to conventional anti-reflux treatment. The patients with acid and non-acid GERC had comparable proportion of esophageal dysmotility (64.9% vs. 48.5%, χ2=3.11, P=0.078), with a shorter break [2.4 (0.7, 5.6) cm vs. 6.1 (1.4, 10.0) cm, Z=-2.39, P=0.017], longer upper esophageal sphincter [(4.1±0.9) cm vs. (3.7±1.3) cm, t=-2.09, P=0.038], higher percentage of normal esophageal contractions [60.0% (17.8%, 90.0%) vs. 30.0% (0, 80.0%), Z=-2.14, P=0.032], and lower percentage of large break [10.0% (0, 40.0%) vs. 50.0% (0, 100.0%), Z=-2.92, P=0.004] in the patients with non-acid GERC. The mean resting pressure of the lower esophageal sphincter was significantly lower (H=7.49, P=0.024), while the percentage of ineffective esophageal contractions was markedly higher (H=8.60, P=0.014) in the patients who responded to intensified anti-reflux treatment and in the patients who did not respond to the anti-reflux therapies. Multifactorial logistic regression analysis identified the percentage of ineffective contraction as an independent factor predicting the efficacy of conventional anti-reflux treatment, with a cut-off value of≤45% and a moderate predictive value (AUC=0.67, P=0.004). Conclusions: Esophageal dysmotility is common in GERC patients with different characteristics in acid and non-acid GERC. The percentage of ineffective esophageal contraction may be a useful indicator for selecting an anti-reflux strategy and predicting treatment outcomes.

Application of the Ion Chamber Array in Magnetic Resonance Accelerator QA

PURPOSE/OBJECTIVE(S)

The magnetic resonance accelerator (MR-Linac) is gradually widely used due to high-quality soft tissue contrast and real-time tracking. However, the special dosimetry characteristics and wide field sizes of MR-Linac increase the QA difficulty with conventional measurement method. The purpose of this study was to confirm an ion chamber array could be used for measuring the beam quality, the profiles, as well as the positioning accuracy of all MLC leaves efficiently, by comparing results with the conventional method. To propose a new QA approach for solving the common problem in data acquisition caused by the wide fields of MR-Linac.

MATERIALS/METHODS

The research was based on a MR-Linac fixed with 1.5T MR and 7MeV energy photon beam. The conventional QA method adopted the MR water tank with a gantry angle of 0°and an SSD of 133.5 cm, both microdiamond and ionization chamber detector were used to acquire the dose profiles (PDD, inline, crossline and diagonal). Field sizes 1 × 1 cm2, 2 × 2 cm2, 3 × 3 cm2, 5 × 5 cm2, 10 × 10 cm2, 15 × 15 cm2, 22 × 22 cm2, 40 × 22 cm2,57 × 22 cm2 were measured with depth 13mm, 50mm, 100mm for vertical beam. As for the wide fields (larger than 15 × 15 cm2), two profiles of x axis (one from left to right, the other from right to left) needed to be gathered and then stitched into one final profile. A boot phantom with an ionization chamber detector was used for measuring beam quality. We defined the profiles measured by conventional method as the baseline. An ion chamber array was adopted to acquire TPR, PDD, profiles and MLC positioning, comparing to the conventional method. The center of ion chamber array was placed to the isocenter of MR-Linac, the array could move to the right and left offset positions through engaging the pin into correct hole of QA platform, such 'once positioning and twice movements' operation could finish within 3 minutes. The central detector of the ion chamber array was used for measuring beam quality. TPRs for different depths were acquired by stacking solid water on the ion chamber array. As for the profiles, we could get the final profile by 'once positioning and twice movements' efficiently. As for the positioning accuracy of MLC leaves, firstly the central leaf pair was put on y = 0 to measure 'open profile' under the open field. Then we moved the MLC leaves to different positions to get the n profile (n for different leaf positions). The ratio of n profile to open profile could show the positioning accuracy of MLC.

RESULTS

We adopted 2D gamma (1mm / 2%) to compare the profiles between the ion chamber array and the conventional method, the results were within 98%. The beam quality consistency of ion chamber array comparing to the wedge tank was within 1% according to daily measurement. The ion chamber array could reflect the MLC positioning differences, the sensitivity was 0.5 mm.

CONCLUSION

The ion chamber array showed a convenient QA method both for the dosimetry and for the MLC positioning accuracy which did reduce the overall measurement time, it was recommended for daily and monthly QA for MR-Linac.

A cane toad (Rhinella marina) N-methyltransferase converts primary indolethylamines to tertiary psychedelic amines

Psychedelic indolethylamines have emerged as potential medicines to treat several psychiatric pathologies. Natural sources of these compounds include 'magic mushrooms' (Psilocybe spp.), plants used to prepare ayahuasca, and toads. The skin and parotid glands of certain toads accumulate a variety of specialized metabolites including toxic guanidine alkaloids, lipophilic alkaloids, poisonous steroids, and hallucinogenic indolethylamines such as DMT, 5-methoxy-DMT, and bufotenin. The occurrence of psychedelics has contributed to the ceremonial use of toads, particularly among Mesoamerican peoples. Yet, the biosynthesis of psychedelic alkaloids has not been elucidated. Herein, we report a novel indolethylamine N-methyltransferase (RmNMT) from cane toad (Rhinella marina). The RmNMT sequence was used to identify a related NMT from the common toad, Bufo bufo. Close homologs from various frog species were inactive, suggesting a role for psychedelic indolethylamine biosynthesis in toads. Enzyme kinetic analyses and comparison with functionally similar enzymes showed that recombinant RmNMT was an effective catalyst and not product inhibited. The substrate promiscuity of RmNMT enabled the bioproduction of a variety of substituted indolethylamines at levels sufficient for purification, pharmacological screening, and metabolic stability assays. Since the therapeutic potential of psychedelics has been linked to activity at serotonergic receptors, we evaluated binding of derivatives at 5-HT1A and 5-HT2A receptors. Primary amines exhibited enhanced affinity at the 5-HT1A receptor compared with tertiary amines. With the exception of 6-substituted derivatives, N,N-dimethylation also protected against catabolism by liver microsomes.

An evolutionary epigenetic clock in plants

Molecular clocks are the basis for dating the divergence between lineages over macroevolutionary timescales (~105 to 108 years). However, classical DNA-based clocks tick too slowly to inform us about the recent past. Here, we demonstrate that stochastic DNA methylation changes at a subset of cytosines in plant genomes display a clocklike behavior. This "epimutation clock" is orders of magnitude faster than DNA-based clocks and enables phylogenetic explorations on a scale of years to centuries. We show experimentally that epimutation clocks recapitulate known topologies and branching times of intraspecies phylogenetic trees in the self-fertilizing plant Arabidopsis thaliana and the clonal seagrass Zostera marina, which represent two major modes of plant reproduction. This discovery will open new possibilities for high-resolution temporal studies of plant biodiversity.

[A close contact of coronavirus disease 2019 with severe imported malaria: a case report]

This article presents a severe cerebral malaria patient in shock with a close contact of COVID-19 that was successfully cured in a negative pressure ward during the global pandemic of COVID-19. The patient experienced a sudden onset of high fever and coma in a designated isolation hotel after returning from Africa, and was transferred to a designated hospital. Following antimalarial therapy, blood pressure elevation, increase of blood volume, bedside hemodialysis, mechanical ventilation, plasma and platelet transfusions, the case gradual recovered.

Use of peripheral blood eosinophils to guide post-operative glucocorticoid therapy in patients with chronic rhinosinusitis with nasal polyps: a randomised, controlled trial

OBJECTIVE

This study aimed to explore the utility of the eosinophil percentage in peripheral blood for guiding post-operative glucocorticoid therapy in patients with chronic rhinosinusitis with nasal polyps.

METHODS

Forty-four patients with chronic rhinosinusitis with nasal polyps underwent functional endoscopic sinus surgery and were randomly divided into two groups. Patients in the standard treatment group used oral and nasal spray glucocorticoids. In the biomarker treatment group, patients with peripheral blood eosinophil percentage values less than 3.05 per cent did not receive glucocorticoid treatment, whereas patients with values 3.05 per cent or above were part of the standard treatment group. Visual Analogue Scale, Sino-Nasal Outcome Test-22 scores, endoscopic Lund-Kennedy scores, eosinophils, interleukin-5 and eosinophil cationic protein in peripheral blood, and nasal secretions were measured.

RESULTS

After functional endoscopic sinus surgery, the Visual Analogue Scale, Sino-Nasal Outcome Test-22 and Lund-Kennedy scores were significantly reduced in both groups; there were no significant differences in those indicators between the groups during the three follow-up visits.

CONCLUSION

Peripheral blood eosinophil percentage offers a potential biomarker to guide post-operative glucocorticoid therapy in patients with chronic rhinosinusitis with nasal polyps.

Randomized phase II adjuvant trial to compare two treatment durations of icotinib (2 years versus 1 year) for stage II-IIIA EGFR-positive lung adenocarcinoma patients (ICOMPARE study)

BACKGROUND

Despite the prolonged median disease-free survival (DFS) by adjuvant targeted therapy in non-small-cell lung cancer patients with epidermal growth factor receptor (EGFR) mutations, the relationship between the treatment duration and the survival benefits in patients remains unknown.

PATIENTS AND METHODS

In this multicenter, randomized, open-label, phase II trial, eligible patients aged 18-75 years with EGFR-mutant, stage II-IIIA lung adenocarcinoma and who had not received adjuvant chemotherapy after complete tumor resection were enrolled from eight centers in China. Patients were randomly assigned (1 : 1) to receive either 1-year or 2-year icotinib (125 mg thrice daily). The primary endpoint was DFS assessed by investigator. The secondary endpoints were overall survival (OS) and safety. This study was registered at ClinicalTrials.gov (NCT01929200).

RESULTS

Between September 2013 and October 2018, 109 patients were enrolled (1-year group, n = 55; 2-year group, n = 54). Median DFS was 48.9 months [95% confidence interval (CI) 33.1-70.1 months] in the 2-year group and 32.9 months (95% CI 26.6-44.8 months) in the 1-year group [hazard ratio (HR) 0.51; 95% CI 0.28-0.94; P = 0.0290]. Median OS for patients was 75.8 months [95% CI 64.4 months-not evaluable (NE)] in the 2-year group and NE (95% CI 66.3 months-NE) in the 1-year group (HR 0.34; 95% CI 0.13-0.95; P = 0.0317). Treatment-related adverse events (TRAEs) were observed in 41 of 55 (75%) patients in the 1-year group and in 36 of 54 (67%) patients in the 2-year group. Grade 3-4 TRAEs occurred in 4 of 55 (7%) patients in the 1-year group and in 3 of 54 (6%) patients in the 2-year group. No treatment-related deaths or interstitial lung disease was reported.

CONCLUSIONS

Two-year adjuvant icotinib was shown to significantly improve DFS and provide an OS benefit in EGFR-mutant, stage II-IIIA lung adenocarcinoma patients compared with 1-year treatment in this exploratory phase II study.

Effectiveness of remimazolam besylate combined with alfentanil for fiberoptic bronchoscopy with preserved spontaneous breathing: a prospective, randomized, controlled clinical trial

OBJECTIVE

The novel short-acting benzodiazepine remimazolam besylate acts rapidly and is used to induce easily controlled sedation. The aim of this study was to investigate the effects of remimazolam besylate combined with alfentanil in patients undergoing fiberoptic bronchoscopy with preserved spontaneous breathing.

PATIENTS AND METHODS

192 patients undergoing painless fiberoptic bronchoscopy were randomly assigned to either propofol (P group) or remimazolam besylate (R group); both groups also received alfentanil 10 µg/kg. The respiratory rate was recorded during the inspection. Mean arterial pressure (MAP), heart rate (HR), oxygen saturation (SpO2), Narcotrend values and Modified Observer's Assessment of Alertness and Sedation (MOAA/S) scores were recorded after entry to the operating room (T0), 1 min (T1), 2 min (T2) and 3 min (T3) after anesthesia, immediately after the bronchoscope entered the vocal cords (T4), when the bronchoscope reached the carina (T5), the patient's eyes opened (T6), and 30 min postoperatively (T7). Secondary outcomes included intraoperative hypotension and body movement grading, etc. RESULTS: There was less respiratory depression during the inspection in the R group than in the P group (p < 0.01). The rate of hypotension during the examination was higher in the P group than in the R group (p < 0.01). Narcotrend values in the P group were less for the R group at the T1-T5 time points (p < 0.01). No difference in the number of body movements ≥ grade 3 was found between the two groups (p > 0.05).

CONCLUSIONS

Remimazolam besylate combined with alfentanil for painless fiberoptic bronchoscopy can better preserve the patient's spontaneous breathing and reduce the incidence of respiratory depression during the inspection than propofol.

Utility of Photon-Counting Detector CT Myelography for the Detection of CSF-Venous Fistulas

CSF-venous fistulas are an increasingly recognized type of CSF leak that can be particularly challenging to detect, even with recently improved imaging techniques. Currently, most institutions use decubitus digital subtraction myelography or dynamic CT myelography to localize CSF-venous fistulas. Photon-counting detector CT is a relatively recent advancement that has many theoretical benefits, including excellent spatial resolution, high temporal resolution, and spectral imaging capabilities. We describe 6 cases of CSF-venous fistulas detected on decubitus photon-counting detector CT myelography. In 5 of these cases, the CSF-venous fistula was previously occult on decubitus digital subtraction myelography or decubitus dynamic CT myelography using an energy-integrating detector system. All 6 cases exemplify the potential benefits of photon-counting detector CT myelography in identifying CSF-venous fistulas. We suggest that further implementation of this imaging technique will likely be valuable to improve the detection of fistulas that might otherwise be missed with currently used techniques.

[RITA selectively inhibits proliferation of BAP1-deficient cutaneous melanoma cells in vitro]

OBJECTIVE

To screen for small molecular compounds with selective inhibitory activity against cutaneous melanoma cells with BAP1 deletion.

METHODS

Cutaneous melanoma cells expressing wild-type BAP1 were selected to construct a BAP1 knockout cell model using CRISPR-Cas9 system, and small molecules with selective inhibitory activity against BAP1 knockout cells were screened from a compound library using MTT assay. Rescue experiment was carried out to determine whether the sensitivity of BAP1 knockout cells to the candidate compounds was directly related to BAP1 deletion. The effects of the candidate compounds on cell cycle and apoptosis were detected with flow cytometry, and the protein expressions in the cells were analyzed with Western blotting.

RESULTS

The p53 activator RITA from the compound library was shown to selectively inhibit the viability of BAP1 knockout cells. Overexpression of wild-type BAP1 reversed the sensitivity of BAP1 knockout cells to RITA, while overexpression of the mutant BAP1 (C91S) with inactivated ubiquitinase did not produce any rescue effect. Compared with the control cells expressing wild-type BAP1, BAP1 knockout cells were more sensitive to RITA-induced cell cycle arrest and apoptosis (P < 0.0001) and showed an increased expression of p53 protein, which was further increased by RITA treatment (P < 0.0001).

CONCLUSION

Loss of BAP1 results in the sensitivity of cutaneous melanoma cells to p53 activator RITA. In melanoma cells, the activity of ubiquitinase in BAP1 is directly related to their sensitivity to RITA. An increased expression of p53 protein induced by BAP1 knockout is probably a key reason for RITA sensitivity of melanoma cells, suggesting the potential of RITA as a targeted therapeutic agent for cutaneous melanoma carrying BAP1-inactivating mutations.