The spatial distribution of immune cell subpopulations in hepatocellular carcinoma

Infiltrating immune cells in the tumor microenvironment (TME) influence tumor progression and patient prognosis, making them attractive therapeutic targets for immunotherapy research. A deeper understanding of immune cell distributions in the TME in hepatocellular carcinoma (HCC) is needed to identify interactions among different immune cell types that might impact the effectiveness of potential immunotherapies. We performed multiplex immunohistochemistry using a tissue microarray of samples from 302 patients with HCC to elucidate the spatial distributions of immune cell subpopulations (CD3⁺, CD4⁺, CD8⁺, CD66b⁺, and CD68⁺) in HCC and normal liver tissues. We analyzed the associations between different immune subpopulations using Pearson''s correlation. G(r) functions, K(r) functions and Euclidean distance were applied to characterize the bivariate distribution patterns among the immune cell types. Cox regression and Kaplan‐Meier analysis were used to evaluate the associations between tumor infiltration by different immune cells and patient outcomes after curative surgery. We also analyzed the relationship between the spatial distribution of different immune cell subpopulations with HCC patient prognosis. We found that the immune cell spatial distribution in the HCC TME is heterogeneous. Our study provides a theoretical basis for HCC immunotherapy.     

Complex decay dynamics of HIV virions,intact and defective proviruses,and 2LTR circles following initiation of antiretroviral therapy

In persons living with HIV-1 (PLWH) who start antiretroviral therapy (ART), plasma virus decays in a biphasic fashion to below the detection limit. The first phase reflects the short half-life (<1 d) of cells that produce most of the plasma virus. The second phase represents the slower turnover (t_1/2 = 14 d) of another infected cell population, whose identity is unclear. Using the intact proviral DNA assay (IPDA) to distinguish intact and defective proviruses, we analyzed viral decay in 17 PLWH initiating ART. Circulating CD4⁺ T cells with intact proviruses include few of the rapidly decaying first-phase cells. Instead, this population initially decays more slowly (t_1/2 = 12.9 d) in a process that largely represents death or exit from the circulation rather than transition to latency. This more protracted decay potentially allows for immune selection. After ∼3 mo, the decay slope changes, and CD4⁺ T cells with intact proviruses decay with a half-life of 19 mo, which is still shorter than that of the latently infected cells that persist on long-term ART. Two-long-terminal repeat (2LTR) circles decay with fast and slow phases paralleling intact proviruses, a finding that precludes their use as a simple marker of ongoing viral replication. Proviruses with defects at the 5′ or 3′ end of the genome show equivalent monophasic decay at rates that vary among individuals. Understanding these complex early decay processes is important for correct use of reservoir assays and may provide insights into properties of surviving cells that can constitute the stable latent reservoir.

For persons living with HIV-1 (PLWH), lifelong adherence to antiretroviral therapy (ART) is critical for maintaining suppression of viral replication and forestalling the development of fatal immunodeficiency. Following initiation of ART, plasma virus levels decay rapidly to below the limit of detection of clinical assays (1–6). Because antiretroviral drugs block new infection of susceptible cells, but not virus production by cells that have an integrated viral genome, this decay must reflect the loss of productively infected cells, cells that were infected prior to the initiation of ART. Productively infected cells could die from viral cytopathic effects, cytolytic host effector mechanisms, or virus-independent T cell turnover. In principle, the decay of plasma virus could also be explained by transition to a nonproductive or latent state of infection. Importantly, the decay is biphasic, indicating the presence of two populations of productively infected cells with different half-lives. Most of the plasma virus is produced by cells that decay very rapidly, with a half-life of less than 1 d. Perelson et al. (4) showed that after most of these cells have decayed, the slope changes, reflecting the slower elimination of a second population of productively infected cells. This population decays with a variable half-life (mean ∼ 2 wk). Although this biphasic decay is a consistent feature of the response to ART, there is still uncertainty about the nature, anatomic location, and fate of the cells responsible for virus production during the first and second phases of decay (referred to here as first- and second-phase cells, respectively). The differences between these two populations have never been elucidated.The first and second phases of decay bring viremia down to below the limit of detection of clinical assays (typically 20 to 50 copies of HIV-1 RNA per mL of plasma) within months of ART initiation, initially raising hope for eradication. However, a latent form of the virus persists in resting memory CD4⁺ T cells (7–14). Initial studies used a quantitative viral outgrowth assay (QVOA) to demonstrate that latently infected resting CD4⁺ T cells purified from PLWH on long-term suppressive ART could be induced to produce replication-competent virus by global T cell activation (8, 9). Longitudinal studies using the QVOA demonstrated that the half-life of the latent reservoir in resting CD4⁺ T cells is 44 mo in PLWH who are adherent to ART. This half-life is long enough to guarantee lifetime persistence of HIV-1 despite ART (12–14). Strategies targeting the latent reservoir in resting CD4⁺ T cells are a major focus of HIV cure research (15–17). In addition to resting CD4⁺ T cells, other cell types may contribute to HIV-1 persistence (18–20).Prior to and immediately following initiation of ART, the frequency of latently infected cells detected by QVOA is substantially higher than frequencies observed in PLWH on long-term ART (21). In principle, several different types of decay processes occurring over the first 6 to 12 mo of treatment could reduce the frequency of latently infected cells to the more stable frequencies observed in PLWH on long-term ART. Early studies by Jerome Zack and Mario Stevenson demonstrated that infected resting CD4⁺ T cells could harbor linear, unintegrated HIV-1 DNA in a state of preintegration latency (22, 23). Following cellular activation, linear unintegrated HIV-1 DNA can be integrated and transcribed, allowing production of virus (22, 23). The half-life of linear, unintegrated forms of the viral genome is not clear, with some studies suggesting that these forms are labile (22, 24–26). Some reverse-transcribed viral genomes can undergo homology-dependent or end-to-end ligation, generating one-long-terminal repeat or two-long-terminal repeat (2LTR) circles, respectively (reviewed in ref. 27). The stability of these forms is also controversial, but they are clearly replication-defective (27–31). Following integration of linear viral cDNA, decay dynamics depend on dynamics of the infected host cells, which can be eliminated by viral cytopathic effects, immune cytolytic effector mechanisms, and normal contraction-phase death of previously activated CD4⁺ T cells (32, 33).While the QVOA provides a definitive minimal estimate of the frequency of latently infected cells, it underestimates reservoir size because not all proviruses in resting CD4⁺ T cells are induced upon one round of maximum T cell activation (34–36). Many replication-competent proviruses require multiple rounds of stimulation for induction. As an alternative to the QVOA, many studies use PCR-based assays to measure proviral DNA. However, the vast majority of HIV-1 proviruses are defective due to apolipoprotein B messenger RNA editing enzyme, catalytic polypeptide-like (APOBEC)-mediated hypermutation or large internal deletions (34, 37–39). PCR-based assays do not distinguish between defective and intact proviruses (40, 41). Although infected cell dynamics have been explored using PCR-based assays (42), the results likely reflect the dynamics of defective proviruses (41). The recently developed intact proviral DNA assay (IPDA) uses two carefully chosen amplicons to probe informative regions of individual proviruses to provide better discrimination between intact and defective proviruses (41, 43). This assay has proven useful in evaluating the long-term dynamics of cells with intact and defective proviruses, demonstrating differences in decay rates that may reflect some vulnerability of cells with intact proviruses to immune effector mechanisms (41, 44, 45).In this study, we use the IPDA to explore the decay of intact and defective proviruses at early time points following initiation of ART. We identify decay processes occurring over intermediate time scales, but with pronounced differences between intact and defective proviruses. Of particular importance is the second-phase decay because infected cells that survive second-phase decay may down-regulate HIV-1 gene expression and enter the stable latent reservoir. Our findings also provide insight into mechanisms for the elimination of the cells with intact viral genomes and into the proper use of assays for the latent reservoir.     

Common occurrence of an antiidiotypic antibody that recognizes T14+ anti-DNA antibodies in patients with systemic lupus erythematosus

Objective. To investigate whether antibodies to a T14 anti-DNA antibody can be found in patients with systemic lupus erythematosus (SLE). Methods. Seventy-six serum samples (37 from patients with SLE) were randomly selected from among sera submitted for routine antinuclear antibody testing. Short, overlapping peptides based on the partial V_H (variable region of the heavy chain) sequence of the T14 antibody were synthesized on multipins and screened for reactivity with SLE sera. In addition, selected peptides from T14 and related proteins were synthesized in bulk and screened for reactivity with both SLE and control sera. A monoclonal antibody was generated to determine the prevalence of the T14 idiotype (T14+ Id) in the different study populations. Results. Antibodies were detected by a peptide based on the third complementarity-determining region (CDR3) of the T14 protein in 15 (41%) of 37 patients with SLE or 15 (54%) of 28 who had anti-DNA antibodies, in 3 (9%) of 34 patients without anti-DNA antibodies (9 of whom had SLE), and in 6 (10%) of 57 healthy controls. In SLE sera, the antiidiotypic (anti-Id) responses (IgM and IgG) correlated well with the anti-DNA responses (IgG), and both responses correlated well with the T14+ Id activity in SLE sera. Control peptides based on the 18/2 (16/6+ Id) and S107 proteins detected low antibody activities in SLE sera, attributable to cross-reactivity with the T14 peptide. A peptide based on an unrelated human antibody was not reactive with these sera. Conclusion. Anti-Id antibodies directed to T14 V_HCDR3 were found commonly in the sera of patients with SLE, and they appeared to be induced by the anti-DNA antibodies present in the sera. Based on these findings, these secondary antibodies may be pathogenic in SLE.     

Singapore Paediatric Resuscitation Guidelines 2021

We present the 2021 Singapore Paediatric Resuscitation Guidelines. The International Liaison Committee on Resuscitation’s Pediatric Taskforce Consensus Statements on Science and Treatment Recommendations, which was published in October 2020, and the updated resuscitation guidelines from the American Heart Association and European Resuscitation Council, were reviewed and discussed by the committee. These recommendations were derived after deliberation of peer-reviewed evidence updates on paediatric resuscitation and took into consideration the local setting and clinical practice.     

Apparent diffusion coefficients in benign and secondary progressive multiple sclerosis by nuclear magnetic resonance

The diffusion characteristics of water in brain white matter were studied in patients with benign and secondary progressive multiple sclerosis (MS), and also in normal controls. In the MS patients, both lesions and normal-appearing white matter (NAWM) were examined to assess whether pathological differences might be evident from the diffusion behavior. A volume-selective technique was used to reduce data acquisition time and improve the reliability and precision of the measurements. This also allowed the time-dependence of apparent diffusion coefficients to be assessed. While lesions from both patient groups showed an elevated diffusion coefficient, no differences between the two groups were found. In addition, NAWM was elevated for both patient groups compared with the control group, although this was only statistically significant for patients with a benign disease course. The degree of elevation of the diffusion coefficient within the individual lesions measured was not related to the disability of the patient. Pathological differences between lesions in patients with different disease courses, if they exist, have not been detected in this study of brain water diffusion.     

Aspirin Enhances the Protective Effect of Progesterone on Trophoblast Cell from Oxidative Stress and Apoptosis

Objective::Clinically, low-dose aspirin and progesterone are frequently used to prevent pregnancy loss. We investigated the effect of these drugs on the biologi...     

美托洛尔对老年食管癌患者围术期心脏功能的保护作用

背景与目的：老年食管癌手术患者逐渐增多,围术期如何保护心脏功能,减少老年患者围术期心脏并发症的发生率及其死亡率成为目前亟待解决的问题之一。β受体阻滞剂在围术期的预防性应用被逐渐受到重视。本研究拟探讨美托洛尔对老年食管癌患者围术期心脏功能的保护作用。方法：将择期开胸手术的老年食管癌患者随机分为美托洛尔组（患者从麻醉诱导前至术后72h应用美托洛尔调节心率）和对照组（不给予美托洛尔）,每组患者30例。分别记录两组术前、给药后、麻醉诱导后2min、插管、插管后4min、切皮、进胸、手术开始后1h、手术结束前10min、手术结束、拔管及拔管后15min的血流动力学指标和肌钙蛋白水平：并统计围术期发生心脏并发症的患者例数及术后窦性心动过速例数。结果：对照组患者气管插管时收缩压升高．与术前比较差异有显著性（P〈0．05）：气管插管及气管拔管时心率增快,与术前比较差异有显著性（P〈0．05）。而美托洛尔组患者在上述各时间点收缩压、心率与术前相比差异无显著性（P〉0．05）。对照组患者围术期有3例肌钙蛋白阳性,美托洛尔组无阳性病例,两组比较无显著性差异（P=0．237）。对照组有6例患者发生心脏并发症,美托洛尔组患者未发生心脏并发症．两组比较差异有显著性（P=0．024）。对照组中2例患者发生急性心肌缺血,4例患者发生房颤,两组患者围术期均未发生心肌梗塞及死亡。对照组患者术后发生窦性心动过速有15例,美托洛尔组有6例,两组比较差异有显著性（P〈0．05）。结论：美托洛尔能降低老年食管癌患者围术期心脏并发症及术后窦性心动过速的发生率,有效抑制气管插管和气管拔管导致的心率增快或血压升高。     

Significance of the lncRNAs MALAT1 and ANRIL in occurrence and development of glaucoma

BackgroundPrimary open‐angle glaucoma (POAG) is the commonest form of glaucoma which is estimated to cause bilaterally blind within 11.1 million people by 2020. Therefore, the primary objectives of this study were to investigate the clinical significance of single‐nucleotide polymorphisms (SNPs) in the lncRNAs MALAT1 and ANRIL in a Chinese Han POAG cohort.MethodsThree hundred and forty‐six glaucoma patients and 263 healthy controls were recruited, and totally 14 SNPs in MALAT1 and ANRIL were genotyped between the two populations.ResultsThe MALAT1 SNPs rs619586 (A>G), rs3200401 (C>T), and rs664589 (C>G) were associated with POAG risk, and the ANRIL SNPs rs2383207 (A>G), rs564398 (A>G), rs2157719 (A>G), rs7865618 (G>A), and rs4977574 (A>G) were associated with POAG (p < 0.05). The MALAT1 haplotypes ACG and ATC, comprised rs619586, rs3200401, and rs664589, increased POAG risk, and the ANRIL haplotype AAGAA, made up of rs2383207, rs7865618, rs4977574, rs564398, and rs2157719, show a significantly increased risk of POAG. In addition, rs619586 (A>G) of MALAT1 and rs564398/rs2157719 of ANRIL were associated with a smaller vertical cup‐to‐disc ratio, while rs619586 of MALAT1 and rs2383207/rs4977574 of ANRIL were associated with higher intraocular pressure in the POAG population.ConclusionSingle‐nucleotide polymorphisms and haplotypes in ANRIL and MALAT1 were associated with POAG onset in our study population, which provide more possibilities to POAG diagnosis and treatment.