Probing for Binding Regions of the FtsZ Protein Surface through Site-Directed Insertions: Discovery of Fully Functional FtsZ-Fluorescent Proteins

FtsZ, a bacterial tubulin homologue, is a cytoskeletal protein that assembles into protofilaments that are one subunit thick. These protofilaments assemble further to form a “Z ring” at the center of prokaryotic cells. The Z ring generates a constriction force on the inner membrane and also serves as a scaffold to recruit cell wall remodeling proteins for complete cell division in vivo. One model of the Z ring proposes that protofilaments associate via lateral bonds to form ribbons; however, lateral bonds are still only hypothetical. To explore potential lateral bonding sites, we probed the surface of Escherichia coli FtsZ by inserting either small peptides or whole fluorescent proteins (FPs). Among the four lateral surfaces on FtsZ protofilaments, we obtained inserts on the front and back surfaces that were functional for cell division. We concluded that these faces are not sites of essential interactions. Inserts at two sites, G124 and R174, located on the left and right surfaces, completely blocked function, and these sites were identified as possible sites for essential lateral interactions. However, the insert at R174 did not interfere with association of protofilaments into sheets and bundles in vitro. Another goal was to find a location within FtsZ that supported insertion of FP reporter proteins while allowing the FtsZ-FPs to function as the sole source of FtsZ. We discovered one internal site, G55-Q56, where several different FPs could be inserted without impairing function. These FtsZ-FPs may provide advances for imaging Z-ring structure by superresolution techniques. IMPORTANCE One model for the Z-ring structure proposes that protofilaments are assembled into ribbons by lateral bonds between FtsZ subunits. Our study excluded the involvement of the front and back faces of the protofilament in essential interactions in vivo but pointed to two potential lateral bond sites, on the right and left sides. We also identified an FtsZ loop where various fluorescent proteins could be inserted without blocking function; these FtsZ-FPs functioned as the sole source of FtsZ. This advance provides improved tools for all fluorescence imaging of the Z ring and may be especially important for superresolution imaging

Clinical outcomes of takotsubo syndrome in patients with cancer: a systematic review and meta-analysis

BackgroundRecent studies suggested a relationship between Takotsubo syndrome (TTS) and malignancy. However, clinical outcomes of TTS associated with cancer have not been assessed completely. This study was aimed to investigate the outcomes of patients with TTS and cancer.MethodsWe performed a systematic review and meta-analysis to evaluate the clinical outcomes of TTS in patients with and without malignancy. We systematically reviewed and analyzed 14 studies (189,210 patients) published in PubMed and Cochrane Library databases until December 2022. The primary outcome was all-cause mortality at the longest follow-up.ResultsThe prevalence of current or previous malignancy in patients with TTS was 8.7% (16,461 patients). Patients with TTS and malignancy demonstrated a higher risk of mortality at the longest follow-up than those with TTS alone (odds ratio [OR], 2.41; 95% confidence interval [CI]; 1.95–2.98; P < 0.001). Moreover, cancer was significantly associated with an increased risk of in-hospital or 30-day mortality (OR 2.36; 95% CI, 1.67–3.33; P < 0.001), shock (OR 1.42; 95% CI, 1.30–1.55; P < 0.001), mechanical respiratory support (OR 1.68; 95% CI, 1.59–1.77; P < 0.001), arrhythmia (OR 1.27; 95% CI, 1.21–1.34; P < 0.001), and major adverse cardiac events (OR 1.69; 95% CI, 1.18–2.442; P < 0.001).ConclusionsThis study revealed significant associations between previous or active cancer and an increased risk of all-cause mortality and in-hospital adverse events in patients with TTS

Efficacy and Safety of Early Intravenous Landiolol on Myocardial Salvage in Patients with ST-segment Elevation Myocardial Infarction before Primary Percutaneous Coronary Intervention: A Randomized Study

Early treatment with an oral β-blocker is recommended in patients with a ST-segment–elevation myocardial infarction (STEMI). In this multicenter study, we evaluated the effects of a continuous administration of landiolol, an ultrashort-acting β-blocker, before primary percutaneous coronary intervention (PCI) on myocardial salvage and its safety in STEMI patients. A total of 47 Japanese patients with anterior or lateral STEMI undergoing a primary PCI within 12 h of symptom onset were randomized to receive intravenous landiolol (started at 3 μg/min/kg dose and continued to a total of 50 mg; n=23) or not (control; n=24). Patients with Killip class III or more were excluded. The primary outcome was the myocardial salvage index on cardiac magnetic resonance imaging (MRI) performed 5-7 days after the PCI. Cardiac MRI was performed in 35 patients (74%). The myocardial salvage index in the landiolol group was significantly greater than that in the control group (44.4±14.6% vs. 31.7±18.9%, respectively; p=0.04). There were no significant differences in adverse events at 24 h between the landiolol and control groups. A continuous administration of landiolol before a primary PCI may increase the degree of myocardial salvage without additional hemodynamic adverse effects within the first 24 h after STEMI

Parental satisfaction and seizure outcome after corpus callosotomy in patients with infantile or early childhood onset epilepsy

AbstractPurposeTo elucidate the benefit of corpus callosotmy in terms of parental satisfaction and seizure outcome.MethodThis study included 16 consecutive patients with infantile or early childhood onset epilepsy who underwent total corpus callosotomy for alleviation of seizures. Questionnaires were sent anonymously to the parents asking about relative changes in seizures and about parental satisfaction for the post-operative outcome.ResultsThe improvements in frequency, intensity, and duration of seizures were correlated with the level of satisfaction (Spearman's rank-order correlation coefficient, ρ=0.87, 0.93, and 0.75, respectively). The highest level of satisfaction was only seen in patients who achieved freedom from all seizures or drop attacks.ConclusionComplete seizure freedom and freedom from drop attacks are important goals of corpus callosotomy for parental satisfaction. These factors should be considered in assessing post-operative outcome after corpus callosotomy

一抗体免疫法によるPorphyromonas. gingivalis SODの定量(プレリミナリーレポート)

Superoxide dismutase (SOD) as a free radical scavenger in Porphyromonas gingivalis is well documented. The aim of this work was to develop an enzyme-linked immunosorbent assay using recombinant P. gingivalis SOD as an antigen. The sandwich complex was detected using a secondary antibody conjugated to β-D-galactosidase. Under optimum conditions, the sensitivity and the limit of detection were determined from 25pg to 500pg. In future, the application will be extended to the expression of SOD from P. gingivalis under various growing conditions

Improved Sendai viral system for reprogramming to naive pluripotency

優れた多分化能を持つヒトのナイーブ型iPS細胞を迅速に作製する方法を発明. 京都大学プレスリリース. 2022-10-18.A novel method for generating naive human iPS cells with significantly higher differentiation potency. 京都大学プレスリリース. 2022-11-15.Naive human induced pluripotent stem cells (iPSCs) can be generated by reprogramming somatic cells with Sendai virus (SeV) vectors. However, only dermal fibroblasts have been successfully reprogrammed this way, and the process requires culture on feeder cells. Moreover, SeV vectors are highly persistent and inhibit subsequent differentiation of iPSCs. Here, we report a modified SeV vector system to generate transgene-free naive human iPSCs with superior differentiation potential. The modified method can be applied not only to fibroblasts but also to other somatic cell types. SeV vectors disappear quickly at early passages, and this approach enables the generation of naive iPSCs in a feeder-free culture. The naive iPSCs generated by this method show better differentiation to trilineage and extra-embryonic trophectoderm than those derived by conventional methods. This method can expand the application of iPSCs to research on early human development and regenerative medicine

Role of Dok-1 and Dok-2 in Myeloid Homeostasis and Suppression of Leukemia

Dok-1 and Dok-2 are closely related rasGAP-associated docking proteins expressed preferentially in hematopoietic cells. Although they are phosphorylated upon activation of many protein tyrosine kinases (PTKs), including those coupled with cytokine receptors and oncogenic PTKs like Bcr-Abl, their physiological roles are largely unidentified. Here, we generated mice lacking Dok-1 and/or Dok-2, which included the double-deficient mice succumbed to myeloproliferative disease resembling human chronic myelogenous leukemia (CML) and chronic myelomonocytic leukemia. The double-deficient mice displayed medullary and extramedullary hyperplasia of granulocyte/macrophage progenitors with leukemic potential, and their myeloid cells showed hyperproliferation and hypo-apoptosis upon treatment and deprivation of cytokines, respectively. Consistently, the mutant myeloid cells showed enhanced Erk and Akt activation upon cytokine stimulation. Moreover, loss of Dok-1 and/or Dok-2 induced blastic transformation of chronic phase CML-like disease in mice carrying the bcr-abl gene, a cause of CML. These findings demonstrate that Dok-1 and Dok-2 are key negative regulators of cytokine responses and are essential for myeloid homeostasis and suppression of leukemia

プールの健康教室に参加することによる心身への影響―低身体活動高齢女性の実態調査―

目的：群馬県内のAプールが実施している健康教室に参加することが心身に及ぼす影響を明らかにすることを目的とした． 方法：研究参加に同意した65歳以上の低身体活動の女性11名を対象者とした．教室参加前に年齢，健康状態，気分を，教室当日に運動前，中，後の血圧・脈拍，主観的運動強度を，教室終了後に気分を調査した．任意で体力測定を行った． 結果：体力測定の結果は，握力，上体起こし，長座体前屈，開眼片足立ち，10m障害物歩行の全てで全国平均よりも低かった．気分は，教室参加後に緊張・不安が有意に低下した．収縮期血圧は運動後では運動前よりも有意に上昇し，脈拍は運動前よりも有意に低下した．主観的運動強度は運動前よりも有意に上昇した． 結論：対象者は，肥満，筋力低下傾向にあるが，集団で実施する水中運動の強度は適度であった．健康教室により，緊張・不安が改善し，適度な運動強度においても血圧や脈拍の有意な変動が認められた．Objectives: The purpose of this study was to investigate the effects of a health class offered at a swimming pool. Methods: The subjects were 11 women aged 65 years or older who had low active mass. We investigated age, health condition, and mood before the health class. On the day of the health class, we measured blood pressure, pulse, and perceived exertion before, during, and after aquatic exercise. We then investigated mood after the health class. We also offered an optional physical fitness test to the subjects. Results: Scores for grip strength, sit-ups, toe touching, one-leg standing with eyes open, and 10-m obstacle walking test results were below healthy levels. The mood test showed that tension and anxiety were improved. Systolic blood pressure was significantly higher, pulse was significantly lower, and the rate of perceived exertion was significantly higher after exercise than before. Conclusions: The subjects were obese and had muscle weakness, but the exercise was of moderate intensity. Tension and anxiety improved after the health class. Significant changes in blood pressure and pulse were found after exercise.原