Enhanced Electrical Conductivity of Polyoxometalates by Bridging with Mixed-valent Multinuclear Platinum Complexes.

Polyoxometalates (POMs) are nanosized molecular metal oxide anion clusters with tuneable structures and functionalities, and they exhibit a redox chemistry and catalytic activity in multielectron redox processes. These are typically poor electrical conductors (< 10-10 Scm-1), which is attributed to negligible electronic interactions among anions in the solid state. Since the reduced electrons on the d0 metals in POMs are delocalized, electrical conductivity was improved when judicious pathways for the electrons were created by bridging the POMs. Utilized with the electronic interactions between bridging oxygen atoms with the highest occupied molecular orbital in the POMs and the metal dz2 orbitals in the multinuclear platinum complexes, and three mixed-valent assemblies were synthesized and characterized. Simply mixing Keggin-type or Dawson-type POMs with tetranuclear or trinuclear platinum complexes in solution afforded three single crystals, and all three compounds were paramagnetic with mixed oxidation states and better conductivities at room temperature than the parent compounds.

Safety Evaluation of Initial CT-P6 Administration for 30 min during the Switch from Reference Trastuzumab in Maintenance Infusion: A Multicenter Observational Study.

CT-P6 is a biosimilar of trastuzumab and is recommended to be administered for 30-90 min in subsequent maintenance infusions to prevent infusion-related reactions (IRRs). We administered CT-P6 for 30 min as the first injection and as an alternative to reference trastuzumab in the maintenance infusion and evaluated the safety of the administration. A total of 140 patients with breast or gastric cancer, who received a switch from tri-weekly reference trastuzumab to CT-P6 for 30 min in maintenance infusions, were retrospectively evaluated. Premedication was administered prior to an infusion of CT-P6 and a cytotoxic agent. However, premedication was not provided when CT-P6 was co-administered with pertuzumab or administered alone. The primary endpoint was the incidence of IRRs. The secondary endpoint was the incidence of diarrhea and skin toxicity. Ninety-five percent of the patients had breast cancer, and 44.3% had advance-stage cancer. The treatment included CT-P6 alone (17.9%) or with cytotoxic agents (23.6%), antihormonal drugs (25.7%), and pertuzumab (62.9%). Median administration time of trastuzumab at the switch was 13 administrations (range 2-140). Premedication was administered to 20.7% patients. One patient (0.7%) experienced grade 3 IRR. The frequency of diarrhea in the reference trastuzumab group and the CT-P6 group was 7.1 and 6.4%, respectively, and that of skin toxicity was 6.4 and 5.0%, respectively, without differences. In conclusion, we first demonstrated that an initial CT-P6 administration for 30 min during the switch from reference trastuzumab in maintenance infusion is an acceptable administration method.

A retrospective analysis of emergency surgery for cases of acute abdomen during cancer chemotherapy. Case series.

BACKGROUND: Treatment for acute abdomen during chemotherapy is frequently difficult because of the complicated status of the patients, and there have been only a few case series summarizing the outcomes of emergent surgery during chemotherapy. The aim of this study was to clarify the clinical outcomes of emergency surgery for acute abdomen during chemotherapy and identify predictive factors associated with mortality. METHODS: We retrospectively analyzed the records of patients who underwent emergency surgery for acute abdomen within 30-days after anti-cancer drugs administration between 2009 and 2020. RESULTS: Thirty patients were identified. The primary malignancies were hematological (n = 7), colorectal (n = 4), lung (n = 4), stomach (n = 2), breast (n = 2), prostate (n = 2) and others (n = 5). Fifteen patients were treated with the regimen, including molecular-targeted anti-cancer drugs (Bevacizumab: 8 cases, Rituximab: 4, Ramucirumab: 2, and Gefitinib: 1). Indications for emergency surgery were perforation of the gastrointestinal tract (n = 24), appendicitis (n = 3), bowel obstruction (n = 2), and gallbladder perforation (n = 1). Severe morbidity (Clavien-Dindo IIIa or more) occurred in 8 cases (27%), and there were 6 in-hospital deaths (20%). Significant factors related to in-hospital death were age >70 years old (P = 0.029), poor performance status (ECOG score 1 or 2) (P = 0.0088), and serum albumin level <2.6 g/dl (P = 0.026). The incidence of acute abdomen (odds ratio 5.31, P = 0.00017) was significantly higher in the patients receiving anti-VEGF drugs than in those without anti-VEGF drugs. CONCLUSION: This study identified three predictive factors associated with in-hospital death after emergency surgery during chemotherapy: an older age, poor performance status, and low serum albumin level.

[A Case of Invasive Lobular Carcinoma of Accessory Mammary Gland That Was Difficult for Evaluate for Lesion Spread].

A 48-year-old female discovered a mass in her left axilla. A thorough examination resulted in a diagnosis of left invasive lobular carcinoma(ILC)of the accessory mammary gland with wide ductal spread. Considering the wide ductal spread, massive resection of the left axilla mass, left lymph node dissection, and a latissimus dorsi musculocutaneous flap procedure were performed. However, histological analysis revealed ILC measuring 80×50 mm with lymph node metastases(5/23)and extensive cancer spread, resulting in a positive surgical margin. It is important to recognize the characteristics of ILC, axillary accessory breast cancer, and the axilla in a treatment strategy.

High temperatures promote cell-to-cell plasmid transformation in Escherichia coli.

Bacteria continuously change their genetic characteristics to adapt to the changing environment by means of horizontal gene transfer. Although three conventional mechanisms of horizontal gene transfer are well known (transformation, transduction, and conjugation), new variations of these mechanisms have also been described. We previously reported that DNase-sensitive cell-to-cell transfer of non-conjugative plasmids, termed as "cell-to-cell transformation," occurs between the cells of two Escherichia coli strains in a co-culture. In this study, to further investigate the mechanism of cell-to-cell transformation, we constructed a new experimental system for cell-to-cell transformation. By using this system, we found that high temperatures of approximately 41ºC-45 °C significantly promote cell-to-cell plasmid transformation. This transfer was much more frequent in solid-air biofilms than in liquid culture, suggesting an importance of biofilm environment. Plasmid transfer frequency reached over 10-7/cell under the optimal strain-plasmid combination and conditions tested. DNase sensitivity test and plasmid isolation from the transformants confirmed the horizontal transfer of full-length plasmids via transformation. Comparative natural transformation experiments, which used similar strains and plasmids under equivalent culture conditions, revealed that cell-to-cell transformation occurs approximately 103 times more frequently than natural transformation, indicating the uniqueness and effectiveness of the cell-to-cell transformation mechanism. As temperatures of approximately 41ºC-45 °C are common in the avian intestines and under some other environmental situations, the phenomenon demonstrated here can occur efficiently in such locations. To the best of our knowledge, this is the first study to demonstrate the enhancing effect of high temperatures on cell-to-cell plasmid transformation in E. coli.

Horizontal Plasmid Transfer by Transformation in Escherichia coli: Environmental Factors and Possible Mechanisms.

Transformation is one mode of horizontal gene transfer (HGT) in bacteria, wherein extracellular naked DNA is taken up by cells that have developed genetic competence. Sensitivity to DNase, which degrades naked DNA, is the key to distinguishing transformation from the DNase-resistant HGT mechanisms. In general, Escherichia coli is not believed to be naturally transformable; it develops high competence only under artificial conditions, including exposure to high Ca2+ concentrations. However, E. coli can reportedly express modest competence under certain conditions that are feasible in natural environments outside laboratory. In addition, recent data suggest that environmental factors influence multiple routes of transformation. In this mini review, we (1) summarize our studies on transformation-based HGT using E. coli experimental systems and (2) discuss the possible occurrence of transformation via multiple mechanisms in the environment and its possible impact on the spread of antibiotic resistance genes.