普米克令舒联合硫酸镁治疗新生儿胎粪吸入综合征的临床研究

目的 探讨普米克令舒联合硫酸镁治疗新生儿胎粪吸入综合征的临床效果.方法 纳入广东省茂名市人民医院2010年4月～2014年4月收治的新生儿胎粪吸入综合征患儿123例.将其分为观察组(n=43)、硫酸镁组(n=40)、普米克令舒组(n=40).观察组采用普米克令舒联合硫酸镁治疗,硫酸镁组给予硫酸镁治疗,普米克令舒组给予普米克令舒治疗.对比分析三组患儿治疗前后动脉血气指标水平、肺动脉收缩压(PASP)、氧暴露时间、住院时间及疗效.结果 观察组治疗后12、24 hpH与同期硫酸镁组和普米克令舒组比较差异无统计学意义(P＞0.05),血氧分压明显高于硫酸镁组和普米克令舒组,动脉血二氧化碳分压明显低于硫酸镁组和普米克令舒组,差异均有统计学意义(P＜0.05);观察组治疗后12、24 h PASP水平明显低于硫酸镁组和普米克令舒组,差异有统计学意义(P＜0.05);观察组氧暴露时间[(5.49±0.85)d]和住院时间[(12.95±2.31)d]均显著短于硫酸镁组[(7.93±1.12)、(16.41±2.57)d]及普米克令舒组[(7.78±1.05)、(16.23±2.41)d],差异有统计学意义(P＜ 0.05);观察组总有效率(86.05％)显著高于硫酸镁组(65.00％)和普米克令舒组(62.50％),差异有统计学意义(P＜0.05).结论 普米克令舒联合硫酸镁治疗新生儿胎粪吸入综合征临床效果显著,具有重要的临床研究价值.     

关节镜下内减压术治疗膝关节半月板囊肿的应用

目的：分析探讨关节镜下减压术治疗膝关节半月板囊肿的临床效果。方法选取该院2012年12月—2013年12月收治的膝关节半月板囊肿患者72例,采用膝关节镜下内减压术及半月板部分或全部切除或缝合治疗,术后指导患者进行膝关节功能锻炼。对所有患者进行随访,术前术后均进行膝关节Lysholm 功能评分,对比观察疗效。结果术前Lysholm 功能评分为（58.6±9.2）分,明显高于术后评分（93.3±4.6）分,术前术后评分对比t=18.167,P<0.05,差异有统计学意义。结论关节镜下减压术及切除或缝合半月板治疗膝关节半月板囊肿具有非常好的疗效,创伤较小,术后患者的膝关节功能恢复情况良好,可以显著提高患者的生活质量,对膝关节稳定性及生理功能干扰较小,值得临床大力推广。     

The Mood Stabilizer Lithium Potentiates the Antidepressant-Like Effects and Ameliorates Oxidative Stress Induced by Acute Ketamine in a Mouse Model of Stress

Background:

Evidence suggests that mammalian target of rapamycin activation mediates ketamine’s rapid but transient antidepressant effects and that glycogen synthase kinase-3β inhibits this pathway. However, ketamine has associated psychotomimetic effects and a high risk of abuse. The mood stabilizer lithium is a glycogen synthase kinase-3 inhibitor with strong antisuicidal properties. Here, we used a mouse stress model to investigate whether adjunct lithium treatment would potentiate ketamine’s antidepressant-like effects.

Methods:

Mice received chronic restraint stress and long-term pre- or postketamine lithium treatment in drinking water. The effects of lithium on ketamine-induced antidepressant-like effects, activation of the mammalian target of rapamycin/brain-derived neurotrophic factor signaling pathways, oxidative stress, and dendritic spine density in the brain of mice were investigated.

Results:

Subtherapeutic (600mg/L) lithium-pretreated mice exhibited an antidepressant-like response to an ineffective ketamine (2.5mg/kg, intraperitoneally) challenge in the forced swim test. Both the antidepressant-like effects and restoration of dendritic spine density in the medial prefrontal cortex of stressed mice induced by a single ketamine (50mg/kg) injection were sustained by postketamine treatment with 1200mg/L of lithium for at least 2 weeks. These benefits of lithium treatments were associated with activation of the mammalian target of rapamycin/brain-derived neurotrophic factor signaling pathways in the prefrontal cortex. Acute ketamine (50mg/kg) injection also significantly increased lipid peroxidation, catalase activity, and oxidized glutathione levels in stressed mice. Notably, these oxidative stress markers were completely abolished by pretreatment with 1200mg/L of lithium.

Conclusions:

Our results suggest a novel therapeutic strategy and justify the use of lithium in patients who benefit from ketamine.     

Early prediction of response to neoadjuvant chemotherapy using contrast-enhanced ultrasound in breast cancer

Early prediction of non-response is essential in order to avoid inefficient treatments. The objective of this study was to determine the contrast-enhanced ultrasound (CEUS) for early predicting pathologic complete response (pCR) to neoadjuvant chemotherapy (NAC) in breast cancer patients.Between March 2018 and October 2019, 93 consecutive patients with histologically proven breast cancer scheduled for NAC were enrolled. Conventional ultrasound and CEUS imaging were performed before NAC and after two cycles of NAC. CEUS parameters were compared with pathologic response. Multiple logistic regression analyses were utilized to explore CEUS parameters to predict pCR, and receiver operating characteristic analysis was used to evaluate the predictive ability.Therapeutic response was obtained from 25 (27%) patients with pCR and 68 (73%) with non-pCR. Compared to non-pCR, pCR cases have a significantly higher proportion of homogeneous enhancement feature (56% vs 14%, P < .001) and centripetal enhancement (52% vs 23%, P = .012). A significant decrease in peak intensity (PI) was observed after two cycles of NAC. Compared with non-pCR patients, the kinetic parameters PI change (PI%) was higher in pCR patients (P < .001). Multiple logistic regression demonstrated two independent predictors of pCR: internal homogeneity (odds ratio, 4.85; 95% confidence interval: 1.20–19.65; P = .027) and PI% (odds ratio, 1.08; 95% confidence interval: 1.02–1.15; P = .007). In receiver operating characteristic curve analysis, internal homogeneity and PI%, with area under curve of 0.71 and 0.84, predicted pCR with sensitivity (56%, 95%) and specificity (85%, 70%), respectively.Internal homogeneity and PI% of CEUS may be useful in the noninvasive early prediction of pCR in patients with breast cancer.     

Treatment of retroperitoneal echinococcosis: the experience of a single center

Retroperitoneal echinococcosis (RE) is a rare condition that is associated with a high mortality and disability rate. It is associated with a high rate of misdiagnosis, a high risk of surgery, and is extremely difficult to manage. There is no uniform standard for determining the exact form of surgical method and the timing of surgery.This was a retrospective analysis of the characteristics and surgical management of patients diagnosed with RE in our hospital between 2012 and 2019.Between 2012 and 2019, 1257 cases of echinococcosis and 121 cases of RE were diagnosed in our hospital. Of these, 68 cases involved surgical treatment, 53 involved non-surgical treatment, and 12 cases were lost to follow-up (4 cases in the surgical group and 8 cases in the non-surgical group). Thus, 109 cases were followed-up. RE cases were divided according to different treatment methods into a radical resection group (Group A, 31 cases), a non-radical resection group (Group B, 37 cases), and a non-surgical group (Group C, 53 cases). We carried out a detailed analysis of the 109 cases experiencing surgical intervention with effective follow-up.Our analysis found that radical resection is the first line of treatment of RE, although non-radical surgery can benefit most patients. It is important to emphasize the importance of the first round of surgery, particularly in cases involving hepatic echinococcosis. If the lesion can be removed radically during the first round of surgery, then radical surgery should be performed.     

Bacterial genome reduction using the progressive clustering of deletions via yeast sexual cycling

The availability of genetically tractable organisms with simple genomes is critical for the rapid, systems-level understanding of basic biological processes. Mycoplasma bacteria, with the smallest known genomes among free-living cellular organisms, are ideal models for this purpose, but the natural versions of these cells have genome complexities still too great to offer a comprehensive view of a fundamental life form. Here we describe an efficient method for reducing genomes from these organisms by identifying individually deletable regions using transposon mutagenesis and progressively clustering deleted genomic segments using meiotic recombination between the bacterial genomes harbored in yeast. Mycoplasmal genomes subjected to this process and transplanted into recipient cells yielded two mycoplasma strains. The first simultaneously lacked eight singly deletable regions of the genome, representing a total of 91 genes and ∼10% of the original genome. The second strain lacked seven of the eight regions, representing 84 genes. Growth assay data revealed an absence of genetic interactions among the 91 genes under tested conditions. Despite predicted effects of the deletions on sugar metabolism and the proteome, growth rates were unaffected by the gene deletions in the seven-deletion strain. These results support the feasibility of using single-gene disruption data to design and construct viable genomes lacking multiple genes, paving the way toward genome minimization. The progressive clustering method is expected to be effective for the reorganization of any mega-sized DNA molecules cloned in yeast, facilitating the construction of designer genomes in microbes as well as genomic fragments for genetic engineering of higher eukaryotes.Complexities of natural biological systems make it difficult to understand and define precisely the roles of individual genes and their integrated functions. The use of model organisms with a relatively small number of genes enables the isolation of core biological processes from their complex regulatory networks for extensive characterization. However, even the simplest natural microbes contain many genes of unknown function, as well as genes that can be singly or simultaneously deleted without any noticeable effect on growth rate in a laboratory setting (Hutchison et al. 1999; Glass et al. 2006; Posfai et al. 2006). Ill-defined genes and those mediating functional redundancies both compound the challenge of understanding even the simplest life forms.Toward generating a minimal cell where every gene is essential for the axenic viability of the organism, we are pursuing strategies to reduce the 1-Mb genome of Mycoplasma mycoides JCVI-syn1.0 (Gibson et al. 2010). Because we can (1) introduce this genome into yeast and maintain it as a plasmid (Benders et al. 2010; Karas et al. 2013a); and (2) “transplant” the genome from yeast into mycoplasma recipient cells (Lartigue et al. 2009), genetic tools in yeast are available for reducing this bacterial genome. Several systems offer advanced tools for bacterial genome engineering. Here we further exploit distinctive features of yeast for this purpose.Methods for serially replacing genomic regions with selectable markers are limited by the number of available markers. One effective approach is to reuse the same marker after precise and scarless marker excision (Storici et al. 2001). We have previously used a self-excising marker (Noskov et al. 2010) six times in yeast to generate a JCVI-syn1.0 genome lacking all six restriction systems (JCVI-syn1.0 ∆1-6) (Karas et al. 2013a). Despite the advantages of scarless engineering, sequential procedures are time-consuming. When applied to poorly characterized genes with the potential to interact with other genes, some paths for multigene knockout may lead to dead ends that result from synergistic mutant phenotypes. When a dead end is reached, sequentially returning to a previous genome in an effort to find a detour to a viable higher-order multimutant may be prohibitively time-consuming.An alternative approach to multigene engineering, available in yeast, is to prepare a set of single mutants and combine the deletions into a single strain via cycles of mating and meiotic recombination (Fig. 1A; Pinel et al. 2011; Suzuki et al. 2011, 2012). With a green fluorescent protein (GFP) reporter gene inserted in each deletion locus, the enrichment of higher-order yeast deletion strains in the meiotic population can be accomplished using flow cytometry. Here we apply this method to the JCVI-syn1.0 ∆1-6 exogenous, bacterial genome harbored in yeast to nonsequentially assemble deletions for genes predicted to be individually deletable based on biological knowledge or transposon-mediated disruption data. The functional identification of simultaneously deletable regions is expected to accelerate the effort to construct a minimal genome.Open in a separate windowFigure 1.Progressive clustering of deleted genomic segments. (A) Scheme of the method. Light blue oval represents a bacterial cell. Black ring or horizontal line denotes a bacterial genome, with the orange box indicating the yeast vector used as a site for linearization and recircularization. Gray shape denotes a yeast cell. Green dot in the genome indicates a deletion replaced with a GFP marker. (B) Map of deleted regions. Orange box indicates the yeast vector sequence used for genome linearization and recircularization. Green boxes indicate regions deleted in multimutant mycoplasma strains. Blue boxes denote restriction modification (RM) systems that are also deleted in the strains. (C) Pulsed-gel electrophoresis result for deleted genomes. The starting strain was the JCVI-syn1.0 ∆1–6 strain (1062 kb). Two strains were analyzed for each design of simultaneous deletion (962 kb for eight-deletion or 974 kb for seven-deletion genome). Ladder is a set of yeast chromosomes (New England BioLabs). (D) GFP-RFP ratio sorting result. Standard sorting was compared with sorting based on a GFP-RFP ratio (Methods).