Epidemiology and Clinical Characteristics of Pediatric Sepsis in PICUs in Southwest China: A Prospective Multicenter Study.

OBJECTIVES: To describe the epidemiological characteristics of pediatric sepsis in Southwest China PICUs. DESIGN: A prospective, multicenter, and observational study. SETTING: Twelve PICUs in Southwest China. PATIENTS: The patients admitted to the PICU from April 1, 2022, to March 31, 2023. The age ranged from 28 days to 18 years. All patients met the criteria of severe sepsis or septic shock. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Of the 31 PICUs invited to participate, 12 PICUs (capacity of 292 beds) enrolled patients in the study. During the study period, 11,238 children were admitted to the participating PICUs, 367 (3.3%) of whom met the diagnosis of severe sepsis or septic shock. The most prevalent sites of infection were the respiratory system (55%) and the digestive system (15%). The primary treatments administered to these patients included antibiotics (100%), albumin (61.3%), invasive mechanical ventilation (58.7%), glucocorticoids (55.6%), blood products (51%), gammaglobulin (51%), and vasoactive medications (46.6%). Sepsis-related mortality in the PICU was 11.2% (41/367). Nearly half of the sepsis deaths occurred within the first 3 days of PICU admission (22/41, 53.7%). The mortality rate of septic shock (32/167, 19.2%) was significantly higher than that of severe sepsis (9/200, 4.5%; p < 0.001). The outcomes of a multivariate logistic regression analysis suggested that a higher pediatric Sequential Organ Failure Assessment score, and the use of invasive mechanical ventilation and vasoactive medications were independently associated with PICU mortality in children with sepsis. CONCLUSIONS: This report updates the epidemiological data of pediatric sepsis in PICUs in Southwest China. Sepsis is still a life-threatening disease in children.

Effects of Ginsenoside Rg1 on the Biological Behavior of Human Amnion-Derived Mesenchymal Stem/Stromal Cells (hAD-MSCs).

Ginsenoside Rg1 (Rg1) is purified from ginseng with various pharmacological effects, which might facilitate the biological behavior of human amnion-derived mesenchymal stem/stromal cells (hAD-MSCs). This study is aimed at investigating the effects of Rg1 on the biological behavior, such as viability, proliferation, apoptosis, senescence, migration, and paracrine, of hAD-MSCs. hAD-MSCs were isolated from human amnions. The effects of Rg1 on the viability, proliferation, apoptosis, senescence, migration, and paracrine of hAD-MSCs were detected by CCK-8, EdU, flow cytometry, SA-ß-Gal staining, wound healing, and ELISA assays, respectively. The protein expression levels were detected by western blot. Cell cycle distribution was evaluated using flow cytometry. We found that Rg1 promoted hAD-MSC cycle progression from G0/G1 to S and G2/M phases and significantly increased hAD-MSC proliferation rate. Rg1 activated PI3K/AKT signaling pathway and significantly upregulated the expressions of cyclin D, cyclin E, CDK4, and CDK2 in hAD-MSCs. Inhibition of PI3K/AKT signaling significantly downregulated the expressions of cyclin D, cyclin E, CDK4, and CDK2, prevented cell cycle progression, and reduced hAD-MSC proliferation induced by Rg1. hAD-MSC senescence rate was significantly increased by D-galactose, while the elevated hAD-MSC senescence rate induced by D-galactose was significantly decreased by Rg1 treatment. D-galactose significantly induced the expressions of senescence markers, p16INK4a, p14ARF, p21CIP1, and p53 in hAD-MSCs, while Rg1 significantly reduced the expressions of those markers induced by D-galactose in hAD-MSCs. Rg1 significantly promoted the secretion of IGF-I in hAD-MSCs. Rg1 reduced the hAD-MSC apoptosis rate. However, the difference was not significant. Rg1 had no influence on hAD-MSC migration. Altogether, our results demonstrate that Rg1 can promote the viability, proliferation, and paracrine and relieve the senescence of hAD-MSCs. PI3K/AKT signaling pathway is involved in the promotive effect of Rg1 on hAD-MSC proliferation. The protective effect of Rg1 on hAD-MSC senescence may be achieved via the downregulation of p16INK4A and p53/p21CIP1 pathway.

Oral contraceptives (OCs) in combination with metformin versus OCs alone on metabolism in nonobese polycystic ovary syndrome: A meta-analysis and systematic review of randomized controlled trials.

BACKGROUND: To compare OCs(oral contraceptives) + metformin and OCs alone for metabolic effects in nonobese polycystic ovary syndrome (PCOS) patients. METHODS: The search was performed in PubMed, EMBASE, the Cochrane Library and clinicaltrials.gov for all published studies up to 30 April 2022 and was limited to English-language articles. All randomized controlled trials (RCTs) comparing OCs + metformin and OCs alone for reproductive-age women with PCOS were included. Data were processed using Revman 5.3 software. RESULTS: Of 396 studies identified, 14 RCTs were included for analysis comprising 707 women. OCs+metformin significantly modified fasting glucose (MD = -0.21 [95% confidence interval (CI) = -0.31, -0.12], p < .00001) and fasting insulin (MD = -2.54 [95%CI = -4.04, -1.04], p = .0009) at study completion compared with OCs alone in nonobese PCOS subjects. There was no statistic difference in the homoeostasis model assessment of insulin resistance (HOMA-IR), high-density lipoprotein (HDL), low-density lipoprotein (LDL), total cholesterol or triglycerides at study end between the two groups. CONCLUSIONS: Metformin, via its positive effects on insulin clearance, in combination with OCs, improved glucose metabolism and offered a good treatment alternative in nonobese women with PCOS.

An integrated study of hormone-related sarcopenia for modeling and comparative transcriptome in rats.

Sarcopenia is a senile disease with high morbidity, serious complications and limited clinical treatments. Menopause increases the risk of sarcopenia in females, while the exact pathogenesis remains unclear. To systematically investigate the development of hormone-related sarcopenia, we established a model of sarcopenia by ovariectomy and recorded successive characteristic changes. Furthermore, we performed the transcriptome RNA sequencing and bioinformatics analysis on this model to explore the underlying mechanism. In our study, we identified an integrated model combining obesity, osteoporosis and sarcopenia. Functional enrichment analyses showed that most of the significantly enriched pathways were down-regulated and closely correlated with endocrine and metabolism, muscle dysfunction, cognitive impairment and multiple important signaling pathways. We finally selected eight candidate genes to verify their expression levels. These findings confirmed the importance of estrogen in the maintenance of skeletal muscle function and homeostasis, and provided potential targets for further study on hormone-related sarcopenia.

Tomography of the source zone of the great 2011 Tohoku earthquake.

The mechanism and rupture process of the giant 2011 Tohoku-oki earthquake (Mw 9.0) are still poorly understood due to lack of permanent near-field observations. Using seismic arrival times recorded by dense seismograph networks on land and at ocean floor, we determine a detailed seismic tomography model of the megathrust zone beneath the Tohoku forearc. Our results show that the coseismic slip of the 2011 Tohoku-oki earthquake initiated at a boundary between a down-dip high-velocity anomaly and an up-dip low-velocity anomaly. The slow anomaly at shallow depths near the Japan trench may reflect low-rigidity materials that are close to the free surface, resulting in large slip and weak high-frequency radiation. Our new tomographic model can account for not only large slip near the trench but also weak high-frequency radiation from the shallow rupture areas.

Arc-arc collision caused the 2018 Eastern Iburi earthquake (M 6.7) in Hokkaido, Japan.

Inland crustal earthquakes usually occur in the brittle upper crust (0-20 km depths), but the 6 September 2018 Eastern Iburi earthquake (M 6.7) took place in southern Hokkaido with a focal depth of ~37 km, causing 41 fatalities and serious damage to the local infrastructure. The reason why this event was so deep and its causal mechanism are still unclear. In this work we study the three-dimensional P and S wave seismic attenuation (1/Q) structure in the source zone of the 2018 Iburi earthquake. Our results show that this event occurred at the boundary between the Sorachi-Yezo belt (low Q) and the dipping Northeastern (NE) Japan arc (high Q) that is descending beneath the Kuril arc. The collision between the NE Japan and Kuril arcs as well as fluids from dehydration of the subducting Pacific plate caused this big event and its unusual focal depth. Similar attenuation structures are revealed in source zones of the 1970 Hidaka earthquake (M 6.7) and the 1982 Urakawa-oki earthquake (M 7.1), suggesting that they were caused by similar processes. We think that large earthquakes will take place again on the active thrust faults in southern Hokkaido in the coming decades. Hence, we should pay much attention to the seismic risk and prepare for reduction of earthquake hazards there.

Effects and possible mechanism of a picosecond pulsed electric field on angiogenesis in cervical cancer in vitro.

Picosecond pulsed electric field (psPEF) is an athermal, minimally invasive and local ablative biomedical engineering technique used in cancer therapy. However, to the best of our knowledge, the effect of psPEF on angiogenesis in cervical cancer is unknown. Therefore, the aim of the current study was to investigate the effects and possible mechanism of psPEF on angiogenesis in cervical cancer in vitro. HeLa cell and human umbilical vein endothelial cell (HUVEC) suspensions were exposed to psPEF with an increasing gradient of electric field intensity (0, 200, 400 and 600 kV/cm). A Cell Counting kit-8 assay and flow cytometry were used to investigate the effect of psPEF on the proliferation and apoptosis of HUVECs. The invasion, migration and tube formation capabilities of HUVECs following psPEF treatment were investigated by Transwell invasion assay, scratch test and lumen formation assay, respectively. Changes in the protein and mRNA levels of angiogenesis-associated factors in HeLa cells were detected by western blot analysis and reverse transcription-quantitative polymerase chain reaction. psPEF was identified to inhibit proliferation and tube formation, and induce apoptosis and necrosis of HUVECs in a dose-dependent manner. psPEF was revealed to decrease the protein and mRNA expression levels of vascular endothelial growth factor and hypoxia-inducible factor 1α in HeLa cells. In summary, psPEF exhibited anti-angiogenic effects in cervical cancer in vitro by exerting direct effects on HUVECs and indirect effects on angiogenesis-associated factors in HeLa cells.

Irreversible electroporation-mediated shRNA knockdown of the HPV18 E6 gene suppresses cervical cancer growth in vitro and in vivo.

Irreversible electroporation (IRE) is a physical, non-thermal cancer therapy, which leads to cell death via permanent membrane permeability. This differs from reversible electroporation (RE), which is used to transfer macromolecules into target cells via transient membrane permeability. Given the electrical impedance of the electric field, RE co-exists outside the central zone of IRE ablation. In the present study, the feasibility of using IRE at a therapeutic dose to mediate short hairpin RNA (shRNA) knockdown of human papillomavirus (HPV)18 E6 in HeLa cervical cancer cells in vitro and in vivo was investigated. Experimental results indicated that the HeLa cells survived the combined treatment with IRE and shRNA plasmid transfection. Additionally, residual tumor tissue in a nude mouse model demonstrated green fluorescence. Subsequent studies showed that the combined treatment inhibited the growth of HeLa cells and tumors. Western blotting analysis showed marked changes in the growth-associated proteins between the combined treatment group and the control. It was concluded that a therapeutic dose of IRE was able to mediate the transfection of HPV18 E6 shRNA into HeLa cervical cancer cells in vitro and in vivo. This combined treatment strategy has promising implications in cancer treatment for the ablation of tumors, and in eliminating microscopic residual tumor tissue.

α-Asarone Attenuates Cognitive Deficit in a Pilocarpine-Induced Status Epilepticus Rat Model via a Decrease in the Nuclear Factor-κB Activation and Reduction in Microglia Neuroinflammation.

BACKGROUND: Temporal lobe epilepsy (TLE) is one of the most drug-resistant types of epilepsy with about 80% of TLE patients falling into this category. Increasing evidence suggests that neuroinflammation, which has a critical role in the epileptogenesis of TLE, is associated with microglial activation. Therefore, agents that act toward the alleviation in microglial activation and the attenuation of neuroinflammation are promising candidates to treat TLE. α-Asarone is a major active ingredient of the Acori Graminei Rhizoma used in Traditional Chinese Medicine, which has been used to improve various disease conditions including stroke and convulsions. In addition, an increasing number of studies suggested that α-asarone can attenuate microglia-mediated neuroinflammation. Thus, we hypothesized that α-asarone is a promising neuroprotective agent for the treatment of the TLE. METHODS: The present study evaluated the therapeutic effects of α-asarone on microglia-mediated neuroinflammation and neuroprotection in vitro and in vivo, using an untreated control group, a status epilepticus (SE)-induced group, and an SE-induced α-asarone pretreated group. A pilocarpine-induced rat model of TLE was established to investigate the neuroprotective effects of α-asarone in vivo. For the in vitro study, lipopolysaccharide (LPS)-stimulated primary cultured microglial cells were used. RESULTS: The results indicated that the brain microglial activation in the rats of the SE rat model led to important learning and memory deficit. Preventive treatment with α-asarone restrained microglial activation and reduced learning and memory deficit. In the in vitro studies, α-asarone significantly suppressed proinflammatory cytokine production in primary cultured microglial cells and attenuated the LPS-stimulated neuroinflammatory responses. Our mechanistic study revealed that α-asarone inhibited inflammatory processes by regulation the transcription levels of kappa-B, by blocking the degradation pathway of kappa B-alpha [inhibitor kappa B-alpha (IκB-α)] and kappa B-beta (IκB-ß) kinase in both the SE rats and in primary cultured microglial cells. CONCLUSION: Taken together, these data demonstrate that α-asarone is a promising neuroprotective agent for the prevention and treatment of microglia-mediated neuroinflammatory conditions including TLE, for which further assessment studies are pertinent.

Epithelialization of mouse ovarian tumor cells originating in the fallopian tube stroma.

Epithelial ovarian carcinoma accounts for 90% of all ovarian cancer and is the most deadly gynecologic malignancy. Recent studies have suggested that fallopian tube fimbriae can be the origin of cells for high-grade serous subtype of epithelial ovarian carcinoma (HGSOC). A mouse HGSOC model with conditional Dicer-Pten double knockout (Dicer-Pten DKO) developed primary tumors, intriguingly, from the fallopian tube stroma. We examined the growth and epithelial phenotypes of the Dicer-Pten DKO mouse tumor cells contributable by each gene knockout. Unlike human ovarian epithelial cancer cells that expressed full-length E-cadherin, the Dicer-Pten DKO stromal tumor cells expressed cleaved E-cadherin fragments and metalloproteinase 2, a mixture of epithelial and mesenchymal markers. Although the Dicer-Pten DKO tumor cells lost the expression of mature microRNAs as expected, they showed high levels of tRNA fragment expression and enhanced AKT activation due to the loss of PTEN function. Introduction of a Dicer1-expressing construct into the DKO mouse tumor cells significantly reduced DNA synthesis and the cell growth rate, with concurrent diminished adhesion and ZO1 epithelial staining. Hence, it is likely that the loss of Dicer promoted mesenchymal-epithelial transition in fallopian tube stromal cells, and in conjunction with Pten loss, further promoted cell proliferation and epithelial-like tumorigenesis.

Effects of irreversible electroporation on cervical cancer cell lines in vitro.

The effects of irreversible electroporation (IRE) on the proliferation, migration, invasion and adhesion of human cervical cancer cell lines HeLa and SiHa were investigated in the present study. HeLa and SiHa cells were divided into a treatment group and control group. The treatment group cells were exposed to electric pulses at 16 pulses, 1 Hz frequency for 100 µsec with 1,000 V/cm strength. Cellular proliferation was determined 24 h after treatment using a Cell Counting Kit­8 (CCK­8) assay and carboxyfluorescein diacetate­succinimidyl ester (CFDA­SE) labeling assay. The different phases of the cell cycle were detected using flow cytometry. Wound healing, Transwell invasion and Matrigel adhesion assays were performed to evaluate the migration, invasion and adhesion abilities of HeLa and SiHa cells. The expression levels of metastasis­associated proteins were determined by western blot analysis. CCK­8 and CFSE labeling assays indicated that the inhibition of cellular proliferation occurs in cells treated with IRE. Additionally, cell cycle progression was arrested at the G1/S phase. A western blot analysis indicated that the expression levels of p53 and p21 proteins were increased, whilst those of cyclin­dependent kinase 2 (CDK2) and proliferating cell nuclear antigen (PCNA) proteins were decreased. However, wound healing, invasion and adhesion assays indicated that cellular migration, invasion and adhesion abilities were not significantly altered following exposure to IRE. IRE was not observed to promote the migration, invasion or adhesion capacity of HeLa and SiHa cells. However, IRE may inhibit the capacity of cells to proliferate and their progression through the cell cycle in vitro. Preliminary evidence suggests that the underlying mechanism involves increased expression levels of p53 and p21 and decreased expression levels of CDK2 and PCNA.

Diagnosis and microecological characteristics of aerobic vaginitis in outpatients based on preformed enzymes.

OBJECTIVE: Aerobic vaginitis (AV) is a recently proposed term for genital tract infection in women. The diagnosis of AV is mainly based on descriptive diagnostic criteria proposed by Donders and co-workers. The objective of this study is to report AV prevalence in southwest China using an objective assay kit based on preformed enzymes and also to determine its characteristics. MATERIALS AND METHODS: A total of 1948 outpatients were enrolled and tested by a commercial diagnostic kit to investigate the AV prevalence and characteristics in southwestern China. The study mainly examined the vaginal ecosystem, age distribution, Lactobacillus amount, and changes in pH. Differences within groups were analyzed by Wilcoxon two-sample test. RESULTS: The AV detection rate is 15.40%. The AV patients were usually seen in the sexually active age group of 20-30 years, followed by those in the age group of 30-40 years. The vaginal ecosystems of all the patients studied were absolutely abnormal, and diagnosed to have a combined infection [aerobic vaginitis (AV) + bacterial vaginitis (BV) 61.33%; 184/300]. Aerobic bacteria, especially Staphylococcus aureus and Escherichia coli, were predominantly found in the vaginal samples of these women. CONCLUSION: AV is a common type of genital infection in southwestern China and is characterized by sexually active age and combined infection predominated by the AV and BV type.

[Picosecond pulsed electric field inhibits the proliferation and migration, induces G2/M phase arrest and promotes apoptosis in human umbilical venous endothelial cells].

OBJECTIVE: To study the impact of intense picosecond pulsed electric field (psPEF) on the biological behaviors of human umbilical venous endothelial cells (HUVECs) in vitro. METHODS: Intense psPEF with constant parameters (pulse duration, 800 ps; recurrence rate, 3 Hz; the number of pulses, 2000) and three-level electric field strength (200, 300 and 400 KV/cm) were performed on HUVECs. CCK-8 assay was used to detect the cell proliferation of HUVECs treated with psPEF for 2, 4, 6, 8, 10, 12, 14, 16 hours. The effect of psPEF on HUVEC migration was measured by wound healing method and Transwell(TM) assay. The apoptosis and cell cycle were detected by flow cytometry. RESULTS: The death rate of HUVECs went up with the increase of the amount of pulses, and the maximum inhibitory rate was at 12 hours after the treatment with psPEF. Intense psPEF inhibited dose-dependently the migration of HUVECs. What's more, the treatment with psPEF arrested cell cycle in G2/M phase and increased the apoptosis rate. CONCLUSION: Intense psPEF inhibits the migration and proliferation of HUVECs as well as induces cell apoptosis and arrests the cell cycle in G2/M phase.

The effects of a picosecond pulsed electric field on angiogenesis in the cervical cancer xenograft models.

OBJECTIVE: The application of picosecond pulsed electric field (psPEF) is a new biomedical engineering technique used in cancer therapy. However, its effects on cervical cancer angiogenesis are not clear. Therefore, the aim of the present study is to investigate the effects of psPEF on angiogenesis in cervical cancer xenograft models. METHODS: Xenograft tumors were created by subcutaneously inoculating nude mice (athymic BALB/c nu/nu mice) with HeLa cells, then were placed closely between tweezer-type plate electrodes and subjected to psPEF with a gradually increased electric field intensity (0kV/cm, 50kV/cm, 60kV/cm, 70kV/cm). The direct effect on tumor tissue was observed by hematoxylin and eosin (H&E) staining and transmission electron microscopy (TEM). The changes of blood vessels and oxygen saturation (sO2) of tumors were monitored in vivo by photoacoustic tomography (PAT). The microvessel density (MVD), vascular endothelial growth factor (VEGF) and hypoxia-inducible transcription factors (HIF-1α and HIF-2α) were detected by immunohistochemical technique (IHC). Their protein expressions and gene transcription levels were evaluated using western blot (WB) and quantitative reverse transcription and polymerase chain reaction (RT-PCR). RESULTS: PsPEF induced obvious necrosis of cervical cancer tissue; with the increasing of electric field intensity, the MVD, vascular PA signal and sO2 values declined significantly. The protein expression and gene transcription levels of VEGF, HIF1α and HIF2α were significantly decreased at the same time. CONCLUSION: PsPEF exhibited dramatic anti-tumor and anti-angiogenesis effects in cervical cancer xenograft models by exerting direct effect on cancer cells and vascular endothelial cells and indirect effect on tumor angiogenesis-related factors.

Molecular changes in endometriosis-associated ovarian clear cell carcinoma.

BACKGROUND: Endometriosis is frequently associated with and thought of having propensity to develop into ovarian clear cell carcinoma (OCCC), although the molecular transformation mechanism is not completely understood. METHODS: We employed immunohistochemical (IHC) staining for marker expression along the potential progression continuum. Expression profiling of microdissected endometriotic and OCCC cells from patient-matched formalin-fixed, paraffin-embedded samples was performed to explore the carcinogenic pathways. Function of novel biomarkers was confirmed by knockdown experiments. RESULTS: PTEN was significantly lost in both endometriosis and invasive tumour tissues, while oestrogen receptor (ER) expression was lost in OCCC relative to endometriosis. XRCC5, PTCH2, eEF1A2 and PPP1R14B were significantly overexpressed in OCCC and associated endometriosis, but not in benign endometriosis (p ⩽ 0.004). Knockdown experiments with XRCC5 and PTCH2 in a clear cell cancer cell line resulted in significant growth inhibition. There was also significant silencing of a panel of target genes with histone H3 lysine 27 trimethylation, a signature of polycomb chromatin-remodelling complex in OCCC. IHC confirmed the loss of expression of one such polycomb target gene, the serous ovarian cancer lineage marker Wilms' tumour protein 1 (WT1) in OCCC, while endometriotic tissues showed significant co-expression of WT1 and ER. CONCLUSIONS: Loss of PTEN expression is proposed as an early and permissive event in endometriosis development, while the loss of ER and polycomb-mediated transcriptional reprogramming for pluripotency may play an important role in the ultimate transformation process. Our study provides new evidence to redefine the pathogenic programme for lineage-specific transformation of endometriosis to OCCC.

Endosalpingiosis as it relates to tubal, ovarian and serous neoplastic tissues: an immunohistochemical study of tubal and Müllerian antigens.

OBJECTIVE: The origins and clinical significance of endosalpingiosis (ES), ectopic tubal epithelium, are not well understood. These investigations aim to characterize ES as it relates to normal fallopian tube, ovarian surface and serous neoplasms. METHODS: A retrospective review of pathology reports from all prophylactic gynecologic surgeries from 2000 to 2010 was performed to assess the frequency of ES. Twenty-one archival specimens of ES, 6 normal fallopian tubes, 9 normal ovaries, 21 serous neoplasms and a commercially available ovarian tissue microarray were subjected to immunohistochemistry (IHC) with 11 tubal and Müllerian antigens. IHC staining was evaluated with a quantitative scoring system and scores were analyzed using MINITAB statistical software. RESULTS: ES was noted in 3.5% of pathologic specimens from 464 prophylactic surgeries. The majority of antigens showed no significant differences (p > 0.05) in median IHC scores between ES and normal fallopian tube epithelium (nFTE), while they were significantly different (p < 0.05) from the ovarian surface epithelium (OSE). Median IHC scores were unchanged in ES tissues regardless of the location of ES or the presence of a concurrent serous neoplasm. Three antigens emerged as contemporary tubal and ES biomarkers: phospho-Smad2, BCL2 and FOXJ1. All 3 biomarkers were expressed in ES, nFTE and serous neoplasms, but not in OSE or other tumor types. CONCLUSION: This study provides immunophenotypic evidence that ES is more similar to the nFTE than OSE. Further, ES biomarker expression closely resembles serous neoplasms strengthening the growing body of evidence that all Müllerian serous carcinomas arise from tubal-like epithelium.

Intense picosecond pulsed electric fields inhibit proliferation and induce apoptosis of HeLa cells.

A picosecond pulsed electric field (psPEF) is a localized physical therapy for tumors that has been developed in recent years, and that may in the future be utilized as a targeted non­invasive treatment. However, there are limited studies regarding the biological effects of psPEF on cells. Electric field amplitude and pulse number are the main parameters of psPEF that influence its biological effects. In this study, we exposed HeLa cells to a psPEF with a variety of electric field amplitudes, from 100 to 600 kV/cm, and various pulse numbers, from 1,000 to 3,000. An MTT assay was used to detect the growth inhibition, while flow cytometry was used to determine the occurrence of apoptosis and the cell cycle of the HeLa cells following treatment. The morphological changes during cell apoptosis were observed using transmission electron microscopy (TEM). The results demonstrated that the cell growth inhibition rate gradually increased, in correlation with the increasing electric field amplitude and pulse number, and achieved a plateau of maximum cell inhibition 12 h following the pulses. In addition, typical characteristics of HeLa cell apoptosis in the experimental groups were observed by TEM. The results demonstrated that the rate of apoptosis in the experimental groups was significantly elevated in comparison with the untreated group. In the treatment groups, the rate of apoptosis was greater in the higher amplitude groups than in the lower amplitude groups. The same results were obtained when the variable was the pulse number. Flow cytometric analysis indicated that the cell cycle of the HeLa cells was arrested at the G2/M phase following psPEF treatment. Overall, our results indicated that psPEF inhibited cell proliferation and induced cell apoptosis, and that these effects occurred in a dose-dependent manner. In addition, the results demonstrated that the growth of the HeLa cells was arrested at the G2/M phase following treatment. This study may provide a foundation for further in vivo experiments, and for the potential clinical application of psPEF in the treatment of cervical cancer.

Picosecond pulsed electric fields induce apoptosis in HeLa cells via the endoplasmic reticulum stress and caspase-dependent signaling pathways.

The non-invasive treatment of tumors with preserved fertility holds great promise. The application of pulsed electric field (PEF) is a new biomedical engineering technique for tumor therapy. Picosecond pulsed electric fields (psPEF) can be transferred to target deep tissue non-invasively and precisely; however, research of the biological effects of psPEF on cells is limited. Electric theory predicts that when the pulse duration decreases to nanoseconds and picoseconds, it will mainly affect organelles and lead to intracellular electromanipulations. Previous studies have shown that psPEF targets the mitochondria and induces apoptosis through a mitochondrial-mediated pathway in HeLa cells. The endoplasmic reticulum is also involved in the intrinsic pathways of apoptosis. In the present study, HeLa cells were exposed to psPEF to investigate the underlying mechanisms of apoptosis. MTT assay demonstrated that psPEF displayed strong growth inhibitory effects on HeLa cells. Treatment with psPEF led to marked cell apoptosis and cell cycle arrest at the G2/M phase. In addition, psPEF affected the phosphorylation levels of endoplasmic reticulum sensors and upregulated the expression of glucose-regulated protein 78 (GRP78), glucose-regulated protein 94 (GRP94) and CCAAT enhancer-binding protein (C/EBP) homologous protein (CHOP). These changes were accompanied by the elevation of intracellular Ca2+ concentrations. Furthermore, the activation of caspase-12, -9 and -3, led to the release of cytochrome c, as well as the upregulation of Bax and the downregulation of Bcl-2, as observed in the HeLa cells. Taken together, these data suggest that psPEF is an efficient apoptosis-inducing agent for HeLa cells, which exerts its effects, at least partially, via the endoplasmic reticulum stress and caspase-dependent signaling pathways.

Intense picosecond pulsed electric fields induce apoptosis through a mitochondrial-mediated pathway in HeLa cells.

The application of pulsed electric fields (PEF) is emerging as a new technique for tumor therapy. Picosecond pulsed electric fields (psPEF) can be transferred to target deep tissue non-invasively and precisely, but the research of the biological effects of psPEF on cells is limited. Electric theory predicts that intense psPEF will target mitochondria and lead to changes in transmembrane potential, therefore, it is hypothesized that it can induce mitochondrial-mediated apoptosis. HeLa cells were exposed to psPEF in this study to investigate this hypothesis. MTT assay demonstrated that intense psPEF significantly inhibited the proliferation of HeLa cells in a dose-dependent manner. Typical characteristics of apoptosis in HeLa cells were observed, using transmission electron microscopy. Loss of mitochondrial transmembrane potential was explored using laser scanning confocal microscopy with Rhodamine-123 (Rh123) staining. Furthermore, the mitochondrial apoptotic events were also confirmed by western blot analysis for the release of cytochrome C and apoptosis-inducing factor from mitochondria into the cytosol. In addition, activation of caspase-3, caspase-9, upregulation of Bax, p53 and downregulation of Bcl-2 were observed in HeLa cells also indicating apoptosis. Taken together, these results demonstrate that intense psPEF induce cell apoptosis through a mitochondrial-mediated pathway.

Percutaneous ultrasound-guided irreversible electroporation: A goat liver study.

Irreversible electroporation (IRE) is a new tumor ablation technique. Pulsed electric fields (PEFs) with permanent duration (100 µsec) permanently permeabilize the cell membrane, causing the formation of innumerable permanent nanopores in the cell membrane and leading to cell death. In this study, percutaneous IRE was performed on 24 goat livers under the guidance of ultrasonography (US). IRE-exposed tissues were pathologically examined and glucose-6-phosphatase (G-6-P) and succinodehydrogenase (SDH) staining were used to detect the activity and function of the endoplasmic reticulum and mitochondria of liver tissues at 0 and 24 h after IRE ablation. Tissue ablation responses were monitored in real-time with US in the percutaneous IRE group; the largest diameter of the ablation zones was measured immediately (D1) and after 24 h (D2). Following D2 measurement, the animals were sacrificed and the gross sections (D3) were measured. The pathological examination results showed complete tissue necrosis after 24 h instead of immediately following IRE. The largest long diameters measured by intraprocedural US immediately after IRE (D1, 39.58±2.13 mm) were larger than those measured by US after 24 h (D2, 37.07±3.51 mm) and in gross section measurements (D3, 36.44±2.04 mm; P<0.05). D1 showed a good linear correlation with D3 (r=0.949). We conclude from these studies that IRE is not an acute ablating effect which leads to cell death. If US-guided percutaneous IRE focused on the target liver areas accurately, physicians would be able to assess the extent of necrosis through the regression equation during the IRE ablation procedure, and evaluate whether sufficient electric field energy had been applied to the desired tissue. Assisted with US guiding and monitoring, the minimally invasive IRE procedure in intraperitoneal lesions may become an important tumor ablation technique.