2022年 · 第135卷第20期

Human gastrointestinal tract harbors trillions of commensal microbes including bacteria, viruses, and fungi to form an ecological community, commonly known as the gut microbiome. Being the second most dominant taxonomic kingdom in the gut (5.8% of total microbiome DNA), enteric viruses are increasingly acknowledged for their roles in shaping the overall composition of the gut microbiome and maintaining human health.^[1,2]Recent advancements in metagenomic sequencing have brought breakthrough in deciphering the features and functions of the gut virome.^[3]Notably, there are several factors restricting the application of this technology in virome study. For instance, the amount of isolated viral DNA from human samples is usually insufficient for metagenomic sequencing. To solve this issue, amplification techniques such as polymerase chain reaction and multiple displacement amplification are widely used to increase the amount of extracted viral DNA prior to sequencing, which in turn could introduce amplification bias, chimeric reads, and random mutations.^[4]Meanwhile, given that most studies analyzed metagenomic reads at low depth (from 0.0003 GB to 7.7 GB),^[5,6]there is currently lack of high quality assembled viral genomes, as well as failure in identifying viruses with low abundance in samples. In addition, Illumina sequencing that generates short reads, has been frequently used. However, short sequencing reads were reported to be inadequate for accurate assembly of viral genomes as they contain hypervariable sequences and repeating regions.^[7]

Cancer immunotherapy has emerged as a promising strategy against triple-negative breast cancer (TNBC). One of the immunosuppressive pathways involves programmed cell death-1 (PD-1) and programmed cell death ligand-1 (PD-L1), but many patients derived little benefit from PD-1/PD-L1 checkpoint blockades treatment. Prior research has shown that MYC, a master transcription amplifier highly expressed in TNBC cells, can regulate the tumor immune microenvironment and constrain the efficacy of immunotherapy. This study aims to investigate the regulatory relationship between MYC and PD-L1, and whether a cyclin-dependent kinase (CDK) inhibitor that inhibits MYC expression in combination with anti-PD-L1 antibodies can enhance the response to immunotherapy.

Public databases and TNBC tissue microarrays were used to study the correlation between MYC and PD-L1. The expression of MYC and PD-L1 in TNBCs was examined by quantitative real-time polymerase chain reaction and Western blotting. A patient-derived tumor xenograft (PDTX) model was used to evaluate the influence of a CDK7 inhibitor THZ1 on PD-L1 expression. Cell proliferation and migration were detected by 5-ethynyl-2′-deoxyuridine (EdU) cell proliferation and cell migration assays. Tumor xenograft models were established for in vivo verification.

A high MYC expression level was associated with a poor prognosis and could alter the proportion of tumor-infiltrating immune cells (TIICs). The positive correlation between MYC and PD-L1 was confirmed by immunostaining samples from 165 TNBC patients. Suppression of MYC in TNBC caused a reduction in the levels of both PD-L1 messenger RNA and protein. In addition, antitumor immune response was enhanced in the TNBC cancer xenograft mouse model with suppression of MYC by CDK7 inhibitor THZ1.

The combined therapy of CDK7 inhibitor THZ1 and anti-PD-L1 antibody appeared to have a synergistic effect, which might offer new insight for enhancing immunotherapy in TNBC.

The study aimed to clarify the characteristics of lymph node metastasis (LNM) and to compare the oncologic outcomes of minimally invasive esophagectomy (MIE) with open esophagectomy (OE) in terms of lymph node dissection (LND) in thoracic esophageal cancer patients.

The data from esophageal cancer patients who underwent MIE or OE from January 2016 to January 2019 were retrospectively reviewed. The characteristics of LNM in thoracic esophageal cancer were discussed, and the differences in numbers of LND, LND rate, and LNM rate/degree of upper mediastinum between MIE and OE were compared.

For overall characteristics of LNM in 249 included patients, the highest rate of LNM was found in upper mediastinum, while LNM rate in middle and lower mediastinum, and abdomen increased with the tumor site moving down. The patients were divided into MIE (n = 204) and OE groups (n = 45). In terms of number of LND, there were significant differences in upper mediastinum between MIE and OE groups (8 [5, 11] vs. 5 [3, 8], P < 0.001). The comparative analysis of regional lymph node showed there was no significant difference except the subgroup of upper mediastinal 2L and 4L group (3 [1, 5] vs. 0 [0, 2], P < 0.001 and 0 [0, 2] vs. 0, P = 0.012, respectively). Meanwhile, there was no significant difference in terms of LND rate except 2L (89.7% [183/204] vs. 71.1% [32/45], P = 0.001) and 4L (41.2% [84/204] vs. 22.2% [10/45], P = 0.018) groups. For LNM rate of T3 stage, there was no significant difference between MIE and OE groups, and the comparative analysis of regional lymph node showed that there was no significant difference except 2L group (11.1% [5/45] vs. 38.1% [8/21], P = 0.025). The LNM degree of OE group was significantly higher than that of MIE group (27.2% [47/173] vs. 7.6% [32/419], P < 0.001), and the comparative analysis of regional LNM degree showed that there was no significant difference except 2L (34.7% [17/49] vs. 7.7% [13/169], P < 0.001) and 4L (23.8% [5/21] vs. 3.9% [2/51], P= 0.031) subgroups.

MIE may have an advantage in LND of upper mediastinum 2L and 4L groups, while it was similar to OE in other stations of LND.

Pre-operative assessment with high-resolution magnetic resonance imaging (MRI) is useful for assessing the risk of local recurrence (LR) and survival in rectal cancer. However, few studies have explored the clinical importance of the morphology of the anterior mesorectum, especially in patients with anterior cancer. Hence, the study aimed to investigate the impact of the morphology of the anterior mesorectum on LR in patients with primary rectal cancer.

A retrospective study was performed on 176 patients who underwent neoadjuvant treatment and curative-intent surgery. Patients were divided into two groups according to the morphology of the anterior mesorectum on sagittal MRI: (1) linear type: the anterior mesorectum was thin and linear; and (2) triangular type: the anterior mesorectum was thick and had a unique triangular shape. Clinicopathological and LR data were compared between patients with linear type anterior mesorectal morphology and patients with triangular type anterior mesorectal morphology.

Morphometric analysis showed that 90 (51.1%) patients had linear type anterior mesorectal morphology, while 86 (48.9%) had triangular type anterior mesorectal morphology. Compared to triangular type anterior mesorectal morphology, linear type anterior mesorectal morphology was more common in females and was associated with a higher risk of circumferential resection margin involvement measured by MRI (35.6% [32/90] vs. 16.3% [14/86], P = 0.004) and a higher 5-year LR rate (12.2% vs. 3.5%, P = 0.030). In addition, the combination of linear type anterior mesorectal morphology and anterior tumors was confirmed as an independent risk factor for LR (odds ratio = 4.283, P = 0.014).

The classification established in this study was a simple way to describe morphological characteristics of the anterior mesorectum. The combination of linear type anterior mesorectal morphology and anterior tumors was an independent risk factor for LR and may act as a tool to assist with LR risk stratification and treatment selection.

Keratinocytes play an important role in wound healing; however, less is known about skin keratinocytes in patients with type 2 diabetes mellitus (T2DM). Therefore, this study aimed to search for the transcriptional characteristics of keratinocytes at the single-cell level from T2DM patients, and to provide experimental data for identifying the pathological mechanisms of keratinocytes under pathological conditions.

We performed single-cell RNA sequencing on the skin tissue from two T2DM patients and one patient without diabetes-induced trauma using the BD Rhapsody^TM Single-Cell Analysis System. With the help of bioinformatics R-based single-cell analysis software, we analyzed the results of single-cell sequencing to identify the single-cell subsets and transcriptional characteristics of keratinocytes at the single-cell level, including Kyoto Encyclopedia of Genes and Genomes and Gene Ontology analyzes.

In this study, we found specific highly expressed signature keratinocyte-related genes. We analyzed the transcriptome of keratinocytes from experimental and control groups and screened a total of 356 differential genes, which were subject to bioinformatics analysis. Enriched pathways included oxidative phosphorylation, antigen processing and presentation, prion and Huntingtons’ diseases, bacterial invasion of epithelial cells, thermogenesis, vasopressin-regulated water reabsorption, and protein processing in the endoplasmic reticulum.

This study revealed the characteristics of keratinocytes at the single-cell level and screened a group of differentially expressed genes related to T2DM-associated keratinocytes, oxidative phosphorylation, cytokine receptor interactions, prion diseases, and other signaling pathways.

Acute kidney injury (AKI) is a common complication in patients, especially elderly patients, who undergo cardiac surgery with cardiopulmonary bypass. Studies have indicated a protective role of autophagy in AKI. However, the mechanisms underlying the regulatory effect of autophagy in AKI among patients undergoing cardiac surgeries are poorly understood. In this study, we aimed to test the hypothesis that exosomal microRNAs (miRNAs) regulate autophagy in tubular epithelial cells after AKI.

Plasma exosomal RNA was extracted from young and elderly AKI patients undergoing cardiac surgery, and the miRNAs expression during the perioperative period were analyzed using next-generation sequencing. The screened miRNAs and their target genes were subjected to gene oncology function and Kyoto Encyclopedia of Genes and Genome enrichment analyses. Renal tubular epithelial cell line (HK-2 cells) was cultured and hypoxia/reoxygenation (H/R) model was established, which is an in vitro renal ischemia/reperfusion (I/R) model. We used Western blot analysis, cell viability assay, transfection, luciferase assay to investigate the mechanisms underlying the observed increases in the levels of renal I/R injury-mediated exosomal miRNAs and their roles in regulating HK-2 cells autophagy.

miR-590-3p was highly enriched in the plasma exosomes of young AKI patients after cardiac surgery. Increased levels of miR-590-3p led to the increases in the expression of autophagy marker proteins, including Beclin-1 and microtubule associated protein 1 light chain 3 beta (LC3II), and prolonged the autophagic response in HK-2 cells after H/R treatment. These effects were achieved mainly via increases in the exosomal miR-590-3p levels, and the tumor necrosis factor receptor-associated factor 6 protein was shown to play a key role in I/R injury-mediated autophagy induction.

Exosomes released from HK-2 cells after renal I/R injury regulate autophagy by transferring miR-590-3p in a paracrine manner, which suggests that increasing the miR-590-3p levels in HK-2 cell-derived exosomes may increase autophagy and protect against kidney injury after renal I/R injury.

A simplified protocol for regional citrate anticoagulation (RCA) using a commercial calcium-containing replacement solution, without continuous calcium infusion, is more efficient for use in continuous renal replacement therapy (CRRT). We aim to design a randomized clinical trial to compare the safety and efficacy between calcium-free and calcium-containing replacement solutions in CRRT with RCA.

Of the 64 patients receiving RCA-based postdilution continuous venovenous hemodiafiltration (CVVHDF) enrolled from 2017 to 2019 in West China Hospital of Sichuan University, 35 patients were randomized to the calcium-containing group and 29 to the calcium-free replacement solution group. The primary endpoint was circuit lifespan and Kaplan-Meier survival analysis was performed. Secondary endpoints included hospital mortality, kidney function recovery rate, and complications. The amount of 4% trisodium citrate solution infusion was recorded. Serum and effluent total (tCa) and ionized (iCa) calcium concentrations were measured during CVVHDF.

A total of 149 circuits (82 in the calcium-containing group and 67 in the calcium-free group) and 7609 circuit hours (4335 h vs. 3274 h) were included. The mean circuit lifespan was 58.1 h (95% CI 53.8-62.4 h) in the calcium-containing group vs. 55.3 h (95% CI 49.7-60.9 h, log rank P = 0.89) in the calcium-free group. The serum tCa and iCa concentrations were slightly lower in the calcium-containing group during CRRT, whereas the postfilter iCa concentration was lower in the calcium-free group. Moreover, the mean amounts of 4% trisodium citrate solution infusion were not significantly different between the groups (171.1 ± 15.9 mL/h vs. 169.0 ± 15.1 mL/h, P = 0.49). The mortality (14/35 [40%] vs. 13/29 [45%], P = 0.70) and kidney function recovery rates of AKI patients (19/26, 73% vs. 14/24, 58%, P = 0.27) were comparable between the calcium-containing and calcium-free group during hospitalization, respectively. Six (three in each group) patients showed signs of citrate accumulation in this study.

When compared with calcium-free replacement solution, RCA-based CVVHDF with calcium-containing replacement solution had a similar circuit lifespan, hospital mortality and kidney outcome. Since the calcium-containing solution obviates the need for a separate venous catheter and a large dose of intravenous calcium solution preparation for continuous calcium supplementation, it is more convenient to be applied in RCA-CRRT practice.

Chinese Clinical Trial Registry (www.chictr.org.cn, ChiCTR-IPR-17012629)

Müllerian duct cysts of the prostate, which are common in young men, are relatively rare clinical complications. Moderately large cysts present with urinary obstruction, urinary tract irritation, subsequent frequent urination, urgency, and dysuria. Larger cysts can compress the seminal vesicles or ejaculatory ducts and cause intractable bloody sperms or obstructive azoospermia. Malignant transformation of Müllerian duct cysts is even rarer. Only 10 cases of Müllerian duct malignancies have been reported in previous studies.^{[1,2,3,4,5,6,7,8,9]}We reported a case of one patient admitted to our center and discussed the clinicopathologic features, diagnosis, treatment, and prognosis of the disease based on literature data. In addition, we performed whole-exome sequencing and analysis of pathological tissues, screened the mutant genes of clear cell carcinoma of Müllerian duct cyst, and preliminarily discussed its pathogenesis.

Super minimally invasive surgery (SMIS) is a new concept proposed in 2016, which is defined as "curing the disease while preserving the integrity of human organ anatomy."^[1]Its concept has been accepted by the World Endoscopy Organization and Chinese Society of Digestive Endoscopy. The obvious advantage of SMIS is to cure diseases without damaging the structure and function of organs. For cancer patients, it can ensure a normal survival time and postoperative quality of life (QoL).^[1]Nevertheless, high-quality comparative studies between SMIS and esophagectomy in the treatment of superficial esophageal squamous cell carcinoma (SESCC) are lacking. Hence, the present study mainly aimed to compare the outcomes of SMIS and esophagectomy directly, especially in terms of QoL and lifestyle.

Thrombocytopenia is a common comorbidity during pregnancy. A platelet (PLT) count of <100 × 10⁹/L is used as the diagnosis for thrombocytopenia. The major adverse effect of thrombocytopenia in the clinical setting is hemorrhage of varying severity.^[1]The causes of thrombocytopenia during pregnancy are distinct from those of other diseases. Gestational thrombocytopenia accounts for >75% of thrombocytopenia cases in pregnant women and occurs in 5% to 8% of pregnancies. Other causes of thrombocytopenia include hemolysis, elevated liver enzymes, low platelet count syndrome, autoimmune thrombocytopenic purpura, and other underlying hematologic diseases.^[2,3]Most women with thrombocytopenia do not require any specific treatment.^[2]For pregnant women whose PLT counts remain low during labor, prophylactic PLT transfusion is used to prevent postpartum hemorrhage. The current guidelines for PLT transfusion in obstetric patients are generally based on following criteria: maintenance of the PLT count >80 × 10⁹/L for patients receiving cesarean section under epidural anesthesia and >50 × 10⁹/L for women giving natural birth without anesthesia.^[4]

To the Editor: Gastric neuroendocrine neoplasms (gNENs) are highly heterogeneous tumors derived from different neuroendocrine cells in the stomach. Recent epidemiological evidence has indicated that gNENs account for 0.3% to 1.8% of all gastric malignancies.^[1]However, few research data are available on gNENs in Chinese patients, but Chinese doctors need to improve their knowledge about this disease.

To the Editor:Multiple myeloma (MM), the second most common hematological malignancy, is caused by clonal proliferation of plasma cells and presents characteristics including anemia, bone pain, renal insufficiency, and hypercalcemia. The adhesion of myeloma cells to the bone marrow (BM) microenvironment results in the mainly intramedullary involvement of MM, and sometimes, however, plasma cells can disseminate and infiltrate into extramedullary (EM) sites, called extramedullary disease (EMD). The prevalence of EMD in MM is 6% to 8% at initial diagnosis and can be as high as 10% to 30% during disease progression/relapse.^[1]An increasing incidence of EMD has been reported over the decades, possibly owing to advances in imaging as well as the growing secondary EMD resulting from prolonged survival. EMD is a highly aggressive disease entity with a poor response to treatment even in the era of novel agents; hence the exploration of pathogenesis and characteristics of extramedullary myeloma (EMM) is of significance.^[2]

To the Editor: Endoscopic sleeve gastroplasty (ESG) is a recently developed incisionless transoral gastroscopic bariatric procedure that can shrink the gastric cavity into a tubular structure similar to the capacity of surgical sleeve gastrectomy by means of endoscopic full-thickness sutures. Clinical practice has proven its safety, durability, minimal invasiveness, and long-term weight loss effects, which are close to those of bariatric surgery.^[1]

To the Editor: Cerebrospinal fluid (CSF) leakage increases the risk of post-operative complications following cranial surgery, and its progression is not always predictable. Currently, surgeons use various methods to achieve watertight closure of CSF, including synthetic sealants, collagen or gelatin based sponges,^[1]and fibrin sealants (FS).^[2,3]Bioseal (Porcine Fibrin Sealant Kit, Guangzhou Bioseal Biotech Co., Ltd., Guangzhou, China) is a virus-inactivated porcine plasma-derived FS that has been approved as a supportive treatment to control surgical bleeding.^[4]Two phase 4 trials (ClinicalTrials.gov, Nos. NCT02094885 and NCT02034799) in two different clinical settings (neurosurgery and vascular surgery) demonstrated that Bioseal is safe and effective as an adjunctive hemostatic agent. This multicenter, prospective, randomized, controlled, single-blinded clinical trial was designed to evaluate the safety and effectiveness of Bioseal as an adjunct to sutured dural closure for achieving intra-operative watertight closure in subjects undergoing cranial neurosurgical procedures.

To the Editor:Combined nuclei stimulation may have a synergistic effect on controlling the symptoms of nervous system diseases and improving quality of life.^[1]However, increasing of leads may increase costs and complications.^[2]Therefore, our study aims to investigate the safety and feasibility of the single curved lead, which can simultaneously reach both subthalamic nucleus (STN) and pedunculopontine nucleus (PPN).

To the Editor:Primary aldosteronism, characterized by hypertension, with or without hypokalemia, is the most frequent form of endocrine hypertension, which is mostly caused by bilateral adrenal hyperplasia or aldosterone-producing adrenocortical adenomas (APAA). However, it can also be induced by aldosterone-producing adrenocortical carcinoma (APAC), which is rare. Because of the rarity and malignancy, the clinical characteristics of APAC and the differences between APAC and APAA remain unclear, and the pre-surgical diagnosis of APAC is valuable. Therefore, we aimed to compare the clinical features of APAA and APAC by extracting data from APAC patient case reports and APAA clinical literature and developing pre-surgery diagnostic criteria for APAC.

To the Editor:Rheumatoid arthritis (RA) is a chronic inflammatory disease characterized by an excess of cardiovascular disease (CVD) risk, estimated to be at least 50% greater than the general population.^[1]CVD has been recognized as the main cause of mortality in established RA patients, but recent data confirm this trend also in earlier stages of the disease.^[2]Several factors have been evoked as determinants of this additional risk, but the most consolidated theory attributes this phenomenon to the interplay between chronic high-grade inflammation and elevated prevalence of "classical" cardiovascular risk factors, including diabetes.

To the Editor: Many physical examination tests are used to diagnose femoroacetabular impingement (FAI). The sensitivity and specificity of the flexion, abduction, and external rotation (FABER) test and the flexion, adduction, and internal rotation (FADIR) test for FAI diagnosis are quite different. Therefore, based on clinical practice, we proposed the possibility of adding a physical examination test to improve the accuracy of the traditional physical examinations.