Glucose starvation induces resistance to metformin through the elevation of mitochondrial multidrug resistance protein 1

Metformin, a drug for type 2 diabetes mellitus, has shown therapeutic effects for various cancers. However, it had no beneficial effects on the survival rate of human malignant mesothelioma (HMM) patients. The present study was performed to elucidate the underlying mechanism of metformin resistance in HMM cells. Glucose‐starved HMM cells had enhanced resistance to metformin, demonstrated by decreased apoptosis and autophagy and increased cell survival. These cells showed abnormalities in mitochondria, such as decreased ATP synthesis, morphological elongation, altered mitochondrial permeability transition pore and hyperpolarization of mitochondrial membrane potential (MMP). Intriguingly, Mdr1 was significantly upregulated in mitochondria but not in cell membrane. The upregulated mitochondrial Mdr1 was reversed by treatment with carbonyl cyanide m‐chlorophenyl hydrazone, an MMP depolarization inducer. Furthermore, apoptosis and autophagy were increased in multidrug resistance protein 1 knockout HMM cells cultured under glucose starvation with metformin treatment. The data suggest that mitochondrial Mdr1 plays a critical role in the chemoresistance to metformin in HMM cells, which could be a potential target for improving its therapeutic efficacy.     

腹膜前引流对腹腔镜经腹腹膜前疝修补术患者术后血肿及血清肿的影响

目的探讨腹腔镜经腹腹膜前疝修补术（TAPP）放置腹膜前引流对术后血肿及血清肿的影响。 方法选取2016年6月至2018年5月，江苏省苏州市中西医结合医院收治的单侧腹股沟疝患者90例，随机分为试验组和对照组，2组患者均行TAPP手术。试验组放置腹膜前引流管，对照组不放置引流管。收集2组患者的一般资料、手术相关资料及随访资料进行统计学分析，对比2组患者术后血肿及血清肿发生率差异。 结果全部患者均完成手术及随访。2组患者的一般资料、疝位置、疝分型、手术时间、住院花费、术后住院时间差异无统计学意义（P>0.05）。2组患者的术后发热发生率、急性疼痛发生率差异无统计学意义（P>0.05）。试验组术后血肿发生率明显低于对照组（P<0.05），试验组患者术后1和3个月血清肿发生率明显低于对照组，差异有统计学意义（P<0.05）。2组患者1年随访均观察到1例复发的病例，差异无统计学意义（P>0.05）；随访期内2组患者均未出现感染的病例。 结论TAPP中，放置腹膜前引流管能够有效降低患者术后血肿和血清肿的发生率，同时并不增加感染和复发风险。     

Pseudocystic pilomatricoma: A new variant and review of the literature

A classic pilomatricoma, which usually presents with an asymptomatic, solitary, firm, subcutaneous nodule in the head, neck, or extremities of the paediatric population, is easily diagnosed based on its characteristic clinical and histopathological features. However, its variants often pose particular diagnostic challenges to clinicians due to their rarity and diverse clinicopathological features. We present a new pseudocystic variant, manifesting as solid lesions floating in a fluid‐filled sac.     

Neuroendocrine,epigenetic, and intergenerational effects of general anesthetics

The progress of modern medicine would be impossible without the use of general anesthetics (GAs). Despite advancements in refining anesthesia approaches, the effects of GAs are not fully reversible upon GA withdrawal. Neurocognitive deficiencies attributed to GA exposure may persist in neonates or endure for weeks to years in the elderly. Human studies on the mechanisms of the long-term adverse effects of GAs are needed to improve the safety of general anesthesia but they are hampered not only by ethical limitations specific to human research, but also by a lack of specific biological markers that can be used in human studies to safely and objectively study such effects. The latter can primarily be attributed to an insufficient understanding of the full range of the biological effects induced by GAs and the molecular mechanisms mediating such effects even in rodents, which are far more extensively studied than any other species. Our most recent experimental findings in rodents suggest that GAs may adversely affect many more people than is currently anticipated. Specifically, we have shown that anesthesia with the commonly used GA sevoflurane induces in exposed animals not only neuroendocrine abnormalities (somatic effects), but also epigenetic reprogramming of germ cells (germ cell effects). The latter may pass the neurobehavioral effects of parental sevoflurane exposure to the offspring, who may be affected even at levels of anesthesia that are not harmful to the exposed parents. The large number of patients who require general anesthesia, the even larger number of their future unexposed offspring whose health may be affected, and a growing number of neurodevelopmental disorders of unknown etiology underscore the translational importance of investigating the intergenerational effects of GAs. In this mini review, we discuss emerging experimental findings on neuroendocrine, epigenetic, and intergenerational effects of GAs.