Field exposure to 50 Hz significantly affects wild-type and unfolded p53 expression in NB69 neuroblastoma cells.

Previous studies have shown that intermittent exposure to a 50 Hz, 100 µT sinusoidal magnetic field (MF) promotes proliferation of human neuroblastoma cells, NB69. This effect is mediated by activation of the epidermal growth factor receptor through a free radical-dependent activation of the p38 pathway. The present study investigated the possibility that the oxidative stress-sensitive protein p53 is a potential target of the MF, and that field exposure can affect the protein expression. To that end, NB69 cells were exposed to short intervals of 30 to 120 min to the aforementioned MF parameters. Two specific anti-p53 antibodies that allow discrimination between the wild and unfolded forms of p53 were used to study the expression and cellular distribution of both isoforms of the protein. The expression of the antiapoptotic protein Bcl-2, whose regulation is mediated by p53, was also analyzed. The obtained results revealed that MF exposure induced increases in p53 gene expression and in protein expression of the wild-type form of p53. Field exposure also caused overexpression of the unfolded form of p53, together with changes in the nuclear/cytoplasmic distribution of both forms of the protein. The expression of protein Bcl-2 was also significantly increased in response to the MF. As a whole, these results indicated that the MF is capable of interacting with the function, distribution and conformation of protein p53. Such interactions could be involved in previously reported MF effects on NB69 proliferation promotion.

Controversias en cirugía: colelitiasis y coledocolitiasis ¿Exploración de vías biliares laparoscópica más colecistectomía laparoscópica (cirugía en un paso) o CPRE y colecistectomía laparoscópica (cirugía en dos pasos)? / Controversies in surgery: Cholelithiasis and choledocholithiasis - Laparoscopic bile duct exploration plus laparoscopic cholecystectomy (one-step surgery) or ERCP and laparoscopic cholecystectomy(two-step surgery)?

Introducción. La colelitiasis tiene una prevalencia del 15 % y el 21 % tendrá coledocolitiasis al momento de la colecistectomía, con 50 % de probabilidad de presentar complicaciones asociadas. Desde el advenimiento de la colecistectomía laparoscópica, el abordaje de la coledocolitiasis ha sido endoscópico, usualmente en un tiempo diferente al vesicular, sin embargo, los avances en laparoscopia han permitido explorar la vía biliar común por la misma vía, pudiendo realizar ambos procedimientos en el mismo tiempo de forma segura. Métodos. Se realizó una búsqueda de la literatura existente con relación al enfoque para el manejo de la colecisto-coledocolitasis en un paso comparado con dos pasos. Resultados. Existe evidencia que demuestra mayor efectividad del abordaje en dos pasos, con CPRE y posterior colecistectomía laparoscópica, sobre el abordaje en un paso, especialmente en la tasa de fuga biliar y de cálculos retenidos. El enfoque en un paso con exploración de vías biliares y colecistectomía laparoscópica en el mismo tiempo es seguro, con alta tasa de éxito, baja incidencia de complicaciones, menor estancia hospitalaria y costos. Conclusión. El abordaje laparoscópico en un solo paso es un procedimiento seguro y eficaz para el manejo de la colecisto-coledocolitiasis, con el beneficio de estancia hospitalaria menor, sin embargo, se requieren habilidades técnicas avanzadas en cirugía laparoscópica. En nuestro medio ya existe una infraestructura para el manejo híbrido con CPRE y colecistectomía laparoscópica, pudiéndose realizar ambos en el mismo tiempo, para reducir estancia y costos.

Introduction. Cholelithiasis has a prevalence of 15%, and 21% will have choledocholithiasis at the time of cholecystectomy, with a 50% probability of presenting associated complications. Since the advent of laparoscopic cholecystectomy, the approach to choledocholithiasis has been endoscopic, normative at a different time than the gallbladder; however, advances in laparoscopy have made it possible to explore the common bile duct by the same route, being able to perform both procedures in a single time safely. Methods. A search of the existing literature was performed regarding the one-step approach compared to the two-step approach for the management of cholelithiasis and choledocholithiasis. Results. There is evidence that demonstrates greater effectiveness of the two-step approach with ERCP and subsequent laparoscopic cholecystectomy over the one-step approach, especially in the rate of bile leak and the incidence of retained stones. The one-step approach with bile duct exploration and laparoscopic cholecystectomy at the same time is safe, with a high success rate, low incidence of complications, shorter hospital stay, and lower costs. Conclusion. The one-step laparoscopic approach is a safe and effective procedure for the management cholelithiasis and concomitant choledocholithiasis, with the benefit of a shorter hospital stay; however, advanced technical skills in laparoscopic surgery are required. In our environment there is already an infrastructure for hybrid management with ERCP and laparoscopic cholecystectomy, both of which can be performed at the same time to reduce hospital stay and costs.

Response of human cancer cells to simultaneous treatment with sorafenib and radiofrequency current.

Due to their alleged analgesic, anti-inflammatory and tissue regenerative effects, capacitive-resistive electrothermal therapy (CRET), which is based on non-invasive exposure to radiofrequency (RF) currents, is often applied to chemotherapeutically treated patients with cancer. Our previous studies have demonstrated that subthermal CRET currents can elicit a number of cell responses, including anti-proliferative effects, in the human liver cancer cell line HepG2. Such effects involve significant changes in the regulation of proteins involved in MAPK signaling pathways, which are also implicated in the cancer cell response to standard anticancer drugs such as sorafenib. This overlap in response pathways may lead to competitive, neutralizing or blocking interactions between the electrical and chemical treatments, thus raising questions on the advisability of CRET treatment for their analgesic, anti-inflammatory or other purposes in patients undergoing chemotherapy. The present study analyzed the effects of simultaneous treatment with sorafenib and 448-kHz, subthermal CRET current on the proliferation and viability of HepG2 cell cultures. Cell viability was assessed through Trypan blue or XTT assays, while flow cytometry was applied for cell cycle and apoptosis analysis. The expression of proteins involved in cell proliferation were assessed by immunoblotting and immunofluorescence. The results revealed no evidence to suggest that the electrical treatment counteracted or neutralized the cellular response to sorafenib at the different conditions evaluated. Furthermore, at the standard pharmacological sorafenib concentration, 5 µM, the combined treatment elicited an anti-proliferative response significantly stronger than that induced by each of the treatments when applied separately in HepG2 cells. These data do not support the hypothesis that CRET exposure may inhibit or diminish the effects of a chemotherapeutic drug used in cancer treatment, and highlights the requirement for further investigation into the cell response to the combined action of electrical and chemical treatments.

Effects of the signal modulation on the response of human fibroblasts to in vitro stimulation with subthermal RF currents.

Capacitive-Resistive Electric Transfer (CRET) thermotherapies aim at tissue repair and regeneration through non-invasive application of RF currents. We have reported that the cellular response to subthermal CRET currents is non-linearly dependent on the signal frequency, and that in vitro exposure to a 448-kHz CRET signal promotes ADSC proliferation, as well as collagen and glycosaminoglycan synthesis in prechondrocytic cells. The present work investigates the response of neonatal fibroblasts to subthermal exposure (100 µA/mm2) to two CRET signals: a 448-kHz, non-modulated sinusoidal wave vs. a 20-kHz amplitude-modulation of the 448-kHz carrier. To that end, cell proliferation and expression of the biomarkers Hsp47, Hsp27 and decorin were assessed by cell count, PCNA and Western blotting. The results revealed that while both signals significantly and equivalently increased early (4 h) expression of Hsp47, the modulated signal was more efficient in inducing Hsp27 and decorin overexpression and promoting cell proliferation. These data indicate that the cellular response is dependent on the RF signal modulation and suggest that the therapeutic effects of CRET could be mediated by promotion of fibroblastic proliferation and overexpression of biomarkers that are essential in skin regeneration.

Role of NADPH oxidase in MAPK signaling activation by a 50 Hz magnetic field in human neuroblastoma cells.

Our previous studies have shown that intermittent exposure to a 50-Hz, 100-µT sine wave magnetic field (MF) promotes human NB69 cell proliferation, mediated by activation of the epidermal growth factor receptor (EGFR) and pathways MAPK-ERK1/2 and p38; being the effects on proliferation and p38 activation blocked by the chelator N-acetylcysteine. The present work investigates the MF effects on free radical (FR) production, and the potential involvement of NADPH oxidase, the main source of reactive oxygen species (ROS), in the MF-induced activation of MAPK pathways. To this end, the field effects on MAPK-ERK1/2, -p38 and -JNK activation in the presence or absence of the NADPH oxidase inhibitor, diphenyleneiodonium chloride (DPI), as well as the expression of the p67phox subunit, were analyzed. The results revealed that field exposure increases FR production and induces early, transient expression of the cytosolic component of the NADPH oxidase, p67phox. Also, the MF-induced activation of the MAPK-JNK pathway, but not that of -ERK1/2 or -p38 pathways, was prevented in the presence of the DPI, which has been shown to significantly reduce p67phox expression. These data, together with those from previous studies, identify various, FR-dependent or -independent mechanisms, involved in the MF-induced proliferative response mediated by MAPK signaling activation.

Tracking mite trophic interactions by multiplex PCR.

BACKGROUND: A thorough knowledge of trophic webs in agroecosystems is essential to achieve successful biological pest control. Phytoseiid mites are the most efficient natural enemies of tetranychid mites, which include several important pests worldwide. Nevertheless, phytoseiids may feed on other food sources including other microarthropods, plants and even other phytoseiids (intraguild predation), which can interfere with biological control services. Molecular gut content analysis is a valuable tool for characterizing trophic interactions, mainly when working on microarthropods such as mites. We have designed new primers for Phytoseiidae, Tetranychidae and Thysanoptera identification and they have been multiplexed in a polymerase chain reaction (PCR) together with universal plant primers. Additionally, we have estimated prey DNA detectability success over time (DS50 ) considering the most probable events in Spanish citrus orchards: the phytoseiid Euseius stipulatus as a predator, the phytoseiid Phytoseiulus persimilis as intraguild prey, and the thrips Frankliniella occidentalis and Anaphothrips obscurus as alternative prey to Tetranychus urticae. RESULTS: The designed multiplex PCR allows the identification of phytoseiids (both predator and intraguild prey) and detects alternative food sources mentioned above in the gut of the phytoseiid predator. DS50 for E. stipulatus as the predator were 1.3, 2.3 and 18.7 h post feeding for F. occidentalis, A. obscurus and P. persimilis as prey, respectively. CONCLUSION: Tracking of the trophic relationships within the citrus acarofauna, and the unveiling of the role of alternative food sources will pave the way for enhancing T. urticae biological control. This multiplex PCR approach could be applicable for these purposes in similar agroecosystems. © 2019 Society of Chemical Industry.

Controversias en cirugía: Erradicación del Helicobacter pylori ¿Terapia a todos o según indicaciones usuales? / Controversies in surgery: Eradication of Helicobacter pylori. Therapy for all or according to usual indications?

La infección por Helicobacter pylori (H. pylori), es la infección bacteriana crónica más frecuente de la raza humana, afecta al 50 % de la población mundial y, por lo menos, al 80 % de la población colombiana. Esta bacteria es re-conocida desde hace más de 15 años como un carcinógeno tipo I. De acuerdo con las indicaciones del Consenso de "Maastricht V" esta infección debe ser buscada y tratada en los pacientes con úlcera péptica activa, linfoma MALT (por sus siglas en inglés, mucosa associated lymphoid tissue), cáncer gástrico temprano, púrpura que presenten síntomas dispépticos crónicos y usuarios crónicos de AINES. Debido al papel que tiene en la fisiopatología del cáncer gástrico, nace la iniciativa de realizar una búsqueda activa del H. pylori y erradicarlo en todas las personas, incluyendo aquellas asintomáticas en países con alta incidencia de esta neoplasia. Existen diversas publicaciones alrededor del mundo que así lo sugieren, mostrando resultados con impacto positivo en el curso y progresión de la enfermedad, sobre todo en las etapas más tempranas de la infección. Sin embargo, otros autores resaltan la creciente problemática de la resistencia bacteriana, y demuestran que el peso estadístico y los diferentes análisis de los estudios disponibles en la actualidad tienen poca validez para dar una recomendación extendida al paciente asintomático. Se cuestiona que tal vez, estamos utilizando las estrategias inadecuadas para manejar una situación de salud pública, ya que estamos enfocados en impactar a cada individuo con terapias antibióticas complejas, en vez de a la población en general con políticas de salud pública

Helicobacter pylori (H. pylori) infection is the most frequent chronic bacterial infection in humans, affecting 50% of the world population, and at least 80% of the Colombian population. This bacteria has been recognized for more than 15 years as a type I carcinogen. According to the indications of the "Maastricht V" consensus, this infection should be sought and treated in patients with: active peptic ulcer, MALT lymphoma (for its acronym Mucosa associated lymphoid tissue), early gastric cancer, purpura who present with chronic dyspeptic symptoms and chronic users of NSAIDs. Due to the role it plays in the pathophysiology of gastric cancer, the initiative was born to carry out an active search for H. pylori and eradicate it in all people, including those asymptomatic in countries with a high incidence of this neoplasia.There are various publications around the world that suggest the effectiveness of this treatment and the positive impact on the course and progression of the disease, especially in the earliest stages of the infection, since the more advanced stages have less encouraging results regarding progression to malignancy. However, other authors highlight the growing problem of bacterial resistance that we are currently facing and demonstrate that the sta-tistical weight and the different analyzes of the currently available studies have little validity to give an extended recommendation to the asymptomatic patient. It is suggested that perhaps inappropriate strategies to manage this public health situation are being used, since we are focused on impacting each individual with complex antibiotic therapies, instead of the general population with public health policies

Opium poisoning in modern times. An overview.

Opium is a substance extracted from Papaver somniferum L that is chronically abused specially in the traditional production regions. Reports on opium poisoning has largely disappeared from the occidental literature on drug problems but recent scientific articles show cases of death related to opium in industrialized countries. This fact led us to consider the interest of knowing the state of the art of acute opium intoxication in modern times. This work shows a compilation of these uncommon cases occurred in different settings and circumstances. Data were obtained by a computer assisted search of the literature using the key words "opium poisoning", "poppy", "poppy seeds", and "papaver somniferum" in PubMed, accompanied by a hand search of the reference lists of all articles for any relevant studies not included in the database. In addition, Google Scholar, government reports, and cases adequately documented on websites were reviewed. Type 1 cases, Accidental opium intoxications when it is used as a recreational drug: Reported cases came mainly from industrialized countries. They were mostly male with a range age of 17-64 years. Many had antecedents of alcoholism or drug abuse and opium tea was used as a substitute of heroin. Rachacha has caused poisonings in France and has been detected in a stash in Spain. Toxicological analysis was documented in forensic cases. The danger of this renewed interest in opium is exemplified in that many of the poisoning cases resulted in fatalities. Type 2 cases, Accidental opium intoxications in children or adults when it used as folk remedy: Pediatric intoxication after the use of opium as folk remedy are mainly published in traditional opium-producing areas with a long history of use or ethnic communities in England or USA. Addiction to opium was common among relatives. Type 3 cases, Opium intoxications with poppy seeds consumed as food: Due to excessive consumption of opium seeds as food, sporadic cases of mild toxicity had been reported and morphine contents were documented. Type 4 cases: Accidental opium intoxications when using the abdominal or pelvic cavity for concealing the drug: Accidental opium body packer intoxications are seen in patients who traveled from illegal opium areas of production. Type 5 cases: Suicides by opium: Opium was a prevalent agent among cases of suicides in Iran but data are scarce.

Involvement of the EGF Receptor in MAPK Signaling Activation by a 50 Hz Magnetic Field in Human Neuroblastoma Cells.

BACKGROUND/AIMS: Previous studies have shown that a 63-hour, intermittent exposure to a 50 Hz, 100 µT magnetic field (MF) induces in the NB69 line of human neuroblastoma a proliferative response that is mediated by activation of the MAPK pathways ERK1/2 and p38. The present study aims to investigate the potential involvement of the epidermal growth factor receptor (EGFR) in the field-induced cell proliferation and activation of MAPK pathways. METHODS: NB69 cultures were MF- or sham-exposed for 5 to 30 minute intervals and 63 hours. Cell proliferation and activation of MAPK-ERK1/2, -p38 and -JNK was analyzed in the presence or absence of erlotinib, an effective inhibitor of EGFR tyrosine kinase. The expression of p-EGFR and MMP-9 in the presence or absence of MF was also studied. Between 3 and 7 replicates of each experiment were performed, using between 3 and 4 samples per experimental condition and replicate. At the end of each replicate, the samples were analyzed at short times (5-30 min) through immunofluorescence and Western blotting, and the growth response was assessed (63 hours interval) through dye exclusion with Trypan blue. RESULTS: The results confirmed that field exposure induces cell proliferation and activation of ERK1/2, p38 and JNK, and revealed that these effects were blocked with erlotinib. The data also showed that, compared to shamexposed controls, the MF exposure induces early and transient increases in the expression of p-EGFR and MMP-9 at 15 and 5 min from the exposure onset, respectively. CONCLUSION: The obtained results reveal that the activation of the MAPK-ERK1/2 and -p38 pathways by the MF is mediated by the EGF receptor. Taken together with our previously published results, this dataset suggests that the proliferative response induced in NB69 by a 63-hour exposure to a weak, power frequency MF, is mediated by early transient activation of EGFR in which MMP-9 would be involved.

Controversias en el manejo de la colecistitis aguda tardía / Controversies in the management of late acute cholecystitis

La colecistitis aguda es la inflamación de la vesícula biliar, en la mayoría de los casos, explicada por la presencia de cálculos mixtos o de colesterol que producen obstrucción y desencadenan factores inflamatorios diversos. La colecistectomía por vía laparoscópica se ha convertido en su tratamiento estándar y definitivo. El procedimiento quirúrgico debe realizarse idealmente en las primeras 72 horas después de iniciados los síntomas, lo que habitualmente se denomina como cuadro agudo. Existe controversia sobre cuál es el manejo más adecuado cuando han pasado más de 72 horas del inicio de los síntomas, condición denominada 'colecistitis aguda tardía', cuando se considera que el proceso inflamatorio es mayor y, el procedimiento, técnicamente más complejo y peligroso.Para esta condición, se han establecido dos estrategias iniciales de manejo: la cirugía temprana ­durante la hospitalización inicial­ o el tratamiento conservador con antibióticos para la supuesta resolución completa de la inflamación, es decir, 'enfriar el proceso'; varias semanas después, se practica una colecistectomía laparoscópica tardía ­diferida o electiva­. Existen muchas publicaciones sobre ambas estrategias, en las que se exponen los beneficios y probables complicaciones de cada una; en la actualidad, se sigue debatiendo sobre el momento óptimo para practicar la intervención quirúrgica. Los trabajos más recientes y con mayor peso epidemiológico, resaltan los beneficios de la cirugía temprana pues, aunque las complicaciones intraoperatorias ocurren en las mismas proporciones, la cirugía en la hospitalización inicial reduce los costos, los reingresos y los tiempos hospitalarios.Después de revisar la literatura disponible a favor y en contra, este artículo pretende recomendar el procedi-miento temprano, inclusive cuando hayan pasado más de tres días de iniciados los síntomas y, solo en casos muy seleccionados, diferir la cirugía (AU)

Acute cholecystitis is the inflammation of the gallbladder, in most cases explained by the presence of mixed or cholesterol stones that produce obstruction by triggering various inflammatory factors; for its definitive management, laparoscopic cholecystectomy became the gold standard, the surgical procedure should ideally be performed within the first 72 hours after the onset of symptoms, which is usually referred to as acute condition; There are controversies in what is the most appropriate management when more than 72 hours have elapsed from the onset of symptoms, a condition called late acute cholecystitis, at which time the inflammatory process is commonly believed to be greater and the procedure more technically complex and dangerous.For this condition, two management strategies have been defined, which consist of early surgery (during index hospitalization) versus initial conservative antibiotic treatment for the supposed complete resolution of the inflammation "cooling the process", followed by a late laparoscopic cholecystectomy several weeks later (deferred, elective); For both strategies, there is abundant literature exposing the benefits and probable complications that concern each one, but at the present time the optimal moment to practice the surgical intervention is still being debated. The most recent works show some benefits in favor of early surgery, since although intraoperative complications occur in the same proportions, surgery in the index hospitalization reduces costs, readmissions, and hospital times. The present article, reviewing the wide literature available for and against, has as main objective to recommend this procedure early, even when more than three days of symptoms have passed, and only in very selected cases, defer surgery (AU)

[EVIDENCE BASED NURSING: EARLY AND SAFE PROTOCOL FOR ICU PATIENT'S MOBILIZATION]. / Enfermería basada en La evidencia. Protocolo para la movilización temprana y segura del paciente en UCI.

UNLABELLED: Patients admitted to the ICU are at risk of immobility and an early and important physical deconditioning. OBJECTIVE: To develop and to implement an early and safe protocol for ICU patients' mobilization. METHODOLOGY: The Evidence Based Practice Model for Staff Nurses was used. It encompasses Assessment, Problem Identification, Planning, Implementation and Evaluation, Integration and Maintenance in Practice. RESULTS: The research team (Advanced Practice Nurse and expert clinical nurses), along with the medical team and rehabilitation service, identified the need to develop the protocol. For its elaboration, a literature search on the data bases PubMed, CINA-HL and Cochrane Library was performed; a questionnaire was administered and structured observations were conducted. For the implementation training sessions were offered to nurses, posters were placed in the unit and protocol was included in the computer program. Finally, an assessment of the knowledge, perceptions and practices of nurses in the unit and a recording of adverse events related to the mobilization will take place. CONCLUSIONS: The development and implementation of a protocol for early mobilization of ICU patients has facilitated the integration of this care in daily practice. This model of evidence-based practice allows nurses an active part in changing the culture in terms of the integration of research into practice.

Power Frequency Magnetic Fields Affect the p38 MAPK-Mediated Regulation of NB69 Cell Proliferation Implication of Free Radicals.

The proliferative response of the neuroblastoma line NB69 to a 100 µT, 50 Hz magnetic field (MF) has been shown mediated by activation of the MAPK-ERK1/2 pathway. This work investigates the MF effect on the cell cycle of NB69, the participation of p38 and c-Jun N-terminal (JNK) kinases in the field-induced proliferative response and the potential involvement of reactive oxygen species (ROS) in the activation of the MAPK-ERK1/2 and -p38 signaling pathways. NB69 cultures were exposed to the 100 µT MF, either intermittently for 24, 42 or 63 h, or continuously for periods of 15 to 120 min, in the presence or absence of p38 or JNK inhibitors: SB203580 and SP600125, respectively. Antioxidant N-acetylcysteine (NAC) was used as ROS scavenger. Field exposure induced transient activation of p38, JNK and ERK1/2. The MF proliferative effect, which was mediated by changes in the cell cycle, was blocked by the p38 inhibitor, but not by the JNK inhibitor. NAC blocked the field effects on cell proliferation and p38 activation, but not those on ERK1/2 activation. The MF-induced proliferative effects are exerted through sequential upregulation of MAPK-p38 and -ERK1/2 activation, and they are likely mediated by a ROS-dependent activation of p38.

Death in a legal poppy field in Spain.

Opium is a substance extracted from Papaver somniferum L. Opium latex contains morphine, codeine, and thebaine and non-analgesic alkaloids such as papaverine and noscapine. In Spain opium growing is allowed only for scientific or pharmaceutical purposes and harvest is supervised by the Spanish Health Ministry. This work describes a sudden fatality involving opium consumption in a legal poppy field. The toxicological and autopsy findings, previous disease, paraphernalia, and scenario are discussed in order to clarify cause and manner of death. A 32-year-old white caucasian male was found unresponsive in a legal poppy field in the South of Spain. The emergency medical services responded to the scene where he was pronounced dead. The friends explained that the deceased had presented with about 30min of convulsions; in spite of trying to keep his airway tract open they noted that "he stayed airless". According to them the victim suffered from epilepsy. Tools found beside his body consisted of plain wood sticks with a blade razor, a fabric handle, and paper. A comprehensive toxicological screening for abuse and psychoactive drugs was performed in the deceased samples. This included ethanol and volatile analysis by HS-GC-FID in peripheral blood and urine, enzyme immunoassay in urine by CEDIA, and a basic drug screening in all samples (including paraphernalia) by GC-MS using modes full scan for screening/confirmation and selected ion monitoring for quantitation. The peripheral blood, urine, vitreous, and gastric content contained the following concentrations of opiates expressed in mg/L (gastric content additionally also expressed in mg total): 0.10, 7.12, 0.23, and 14.80 (2.81mg total) of thebaine, 0.13, 4.50, 0.13, and 6.60 (1.25mg total) of morphine (free), 0.48, 0.88, 0.17, and 1.50 (0.28mg total) of codeine. These tree opiates were also detected in the tools (paraphernalia) used by the deceased for opium consumption. Other toxicological findings were metabolites of cocaine and cannabis. Apparently the victim stole poppy capsules and ingested an unknown quantity of the latex with the goal to obtain euphoric effects. The cause of death was considered poly-drug toxicity with a preponderant role of thebaine and morphine. In addition, the epileptic condition of the deceased could have played a role. As far as we know, there are no previous reports of fatalities occurring in legal poppy fields.

Power-Frequency Magnetic Field Inhibits Adipogenic Differentiation in Human ADSC.

BACKGROUND/AIMS: Semicircular lipoatrophy (SL) is an idiopathic condition characterized by atrophy of subcutaneous fatty tissue. Although several studies have suggested a possible association between SL and occupational exposure to power frequency magnetic fields (MF), no mechanism has been proposed so far that explains an influence of these fields on adipogenesis. METHODS: The study investigates the effects of a 50 Hz, 100 µT MF on the adipogenesis of stem cells isolated from human adipose tissue (ADSC). Cells were plated in Petri dishes and either exposed intermittently to the field for 42 hours or sham-exposed. RESULTS: Field exposure significantly reduced lipid accumulation within the cells, revealed in Oil Red O stained samples by spectrophotometry and colorimetry. Early cell passages were particularly sensitive to the effect: 30.40 ± 5.77% and 47.96 ± 12.47% below controls in the spectrophotometric and colorimetric assays, respectively. Such antiadipogenic effect was accompanied by significant changes in the expression of key effectors/regulators of early adipogenesis: PPARx03B3;, p-ERK1/2 and Sox9, indicating that at least the ERK/PPARx03B3; signaling pathway could be involved in the effect. CONCLUSIONS: These results constitute an experimental support to the hypothesis that power frequency MF can be one of the factors involved in the etiology of SL.

Retinoic acid inhibits the cytoproliferative response to weak 50­Hz magnetic fields in neuroblastoma cells.

We previously reported that intermittent exposure to a 50­Hz magnetic field (MF) at 100 µT stimulates cell proliferation in the human neuroblastoma cell line NB69. The present study aimed to investigate whether the magnetic field-induced growth promotion also occurs at a lower magnetic flux density of 10 µT. To this purpose, NB69 cells were subjected for 42 h to intermittent exposure, 3 h on/3 h off, to a 50­Hz MF at a 10 or 100 µT magnetic flux density. The field exposure took place either in the presence or in the absence of the antiproliferative agent retinoic acid. At the end of the treatment and/or incubation period, the cell growth was estimated by hemocytometric counting and spectrophotometric analysis of total protein and DNA contents. Potential changes in DNA synthesis were also assessed through proliferating cell nuclear antigen (PCNA) immunolabeling. The results confirmed previously reported data that a 42-h exposure to a 50­Hz sine wave MF at 100 µT promotes cell growth in the NB69 cell line, and showed that 10 µT induces a similar proliferative response. This effect, which was significantly associated and linearly correlated with PCNA expression, was abolished by the presence of retinoic acid in the culture medium.

Antagonistic effects of a 50 Hz magnetic field and melatonin in the proliferation and differentiation of hepatocarcinoma cells.

BACKGROUND/AIMS: Epidemiological and experimental evidence exists indicating that exposure to weak, extremely low frequency magnetic fields (ELF - MF) could affect cancer progression. It has been proposed that such hypothetical action could be mediated by MF-induced effects on the cellular response to melatonin (MEL), a potentially oncostatic neurohormone. The present study investigates the response of HepG2 cells to intermittent exposure to a 50 Hz, 10 µT MF, in the presence or absence of MEL at physiological (10 nM) or pharmacological doses (1 µM). METHODS: The Trypan blue cell exclusion test, BrdU incorporation and PCNA expression assays were carried out to assess the cellular response in terms of viability and proliferation. In addition, albumin and alpha-fetoprotein, were analyzed as specific hepatocellular differentiation markers. RESULTS: The results indicate that the MF exerts significant cytoproliferative and dedifferentiating effects that can be prevented by 10 nM MEL. Conversely, MEL exerts cytostatic and differentiating effects on HepG2 that are abolished by simultaneous exposure to MF. CONCLUSION: As a whole, these results support the hypothesis that ELF - MF and MEL exert opposite, mutually counteracting effects on cell proliferation and differentiation.

The proliferative response of NB69 human neuroblastoma cells to a 50 Hz magnetic field is mediated by ERK1/2 signaling.

A number of studies have reported that extremely low frequency magnetic fields (ELF-MF) can modulate proliferative processes in vitro; however, the transduction mechanisms implicated in such phenomena remain to be identified. The present study was aimed to determine whether a 50 Hz, 100 µT MF can induce cell proliferation in the human neuroblastoma line NB69, and whether the signaling pathway MAPK-ERK1/2 (Mitogen-Activated Protein Kinase - Extracellular-Signal-Regulated Kinase 1 and 2) is involved in that proliferative response. The cultures were exposed intermittently or continuously to the MF for a 63-hour duration. The continuous treatment did not induce significant changes in cell proliferation. In contrast, intermittent exposure caused statistically significant increase in the percent of cells in phase S of the cell cycle, followed by a significant increase in cell number. The intermittent treatment also induced an early, transient and repetitive activation of ERK1/2 that could be involved in the proliferative effects. In fact, both the proliferative response and the repeated activation of ERK1/2 were blocked by PD98059, the specific inhibitor of MEK (ERK kinases 1 and 2). Taken together, the described results indicate that a 50 Hz, 100 µT MF can stimulate proliferation in NB69 cells by triggering MAPK-ERK1/ 2 signaling at each of the "On" periods of an intermittent exposure.

Influence of a 50 Hz magnetic field and of all-trans­retinol on the proliferation of human cancer cell lines.

In vitro exposure to power frequency magnetic fields (MF) has been reported to influence cell proliferation and differentiation. However, the nature of the response of different human cancer cell types to these fields has not been sufficiently characterized. The present work investigates the response of two proliferating human cell lines of neuroblastoma (NB69) and hepatocarcinoma (HepG2) to a 42 h, intermittent treatment with a weak, 100 µT, 50 Hz MF, alone or in combination with 0.5 µM all-trans-retinol (ROL), a retinoid currently applied in oncostatic therapies. In each experimental replicate the cell samples were submitted to one of the following treatment combinations: MF+/ROL+, MF+/ROL-, MF-/ROL+ or MF-/ROL-. The proliferative response was determined by cell counting (Trypan blue exclusion), BrdU incorporation and by spectrophotometric analysis of total protein and DNA content. The results show that when administered separately, the two treatments, MF and ROL, significantly enhanced cell proliferation in both cell lines. In NB69 simultaneous administration of MF and ROL induced an additive effect on cell proliferation, associated to increased DNA content. By contrast, in HepG2 the ROL-induced cell proliferation and increased protein content were partially blocked by simultaneous exposure to MF. Taken together, these data show that both agents, a weak MF and ROL at a low concentration, induce proliferative responses in the two assayed human cell lines. However, significant differences were observed between the responses of the two cellular species to the combined treatment with ROL and MF, indicating that the mechanisms underlying the cellular response to each of the two agents can mutually interact in a manner that is cell type-specific.

Reporting a sudden death due to accidental gasoline inhalation.

The investigation of uncertain fatalities requires accurate determination of the cause of death, with assessment of all factors that may have contributed to it. Gasoline is a complex and highly variable mixture of aliphatic and aromatic hydrocarbons that can lead to cardiac arrhythmias due to sensitization of the myocardium to catecholamines or acts as a simple asphyxiant if the vapors displace sufficient oxygen from the breathing atmosphere. This work describes a sudden occupational fatality involving gasoline. The importance of this petroleum distillate detection and its quantitative toxicological significance is discussed using a validated analytical method. A 51 year-old Caucasian healthy man without significant medical history was supervising the repairs of the telephone lines in a manhole near to a gas station. He died suddenly after inhaling gasoline vapors from an accidental leak. Extensive blistering and peeling of skin were observed on the skin of the face, neck, anterior chest, upper and lower extremities, and back. The internal examination showed a strong odor of gasoline, specially detected in the respiratory tract. The toxicological screening and quantitation of gasoline was performed by means of gas chromatography with flame ionization detector and confirmation was performed using gas chromatography-mass spectrometry. Disposition of gasoline in different tissues was as follows: heart blood, 35.7 mg/L; urine, not detected; vitreous humor, 1.9 mg/L; liver, 194.7 mg/kg; lung, 147.6 mg/kg; and gastric content, 116,6 mg/L (2.7 mg total). Based upon the toxicological data along with the autopsy findings, the cause of death was determined to be gasoline poisoning and the manner of death was accidental. We would like to alert on the importance of testing for gasoline, and in general for volatile hydrocarbons, in work-related sudden deaths involving inhalation of hydrocarbon vapors and/or exhaust fumes.

Assessment of occupational exposure to extremely low frequency magnetic fields in hospital personnel.

It has been proposed that chronic exposure to extremely low frequency (ELF) magnetic fields (MF) in occupational environments could represent a risk factor for a number of disorders. Medical and technical workers in hospitals have been reported to be exposed to relatively strong ELF fields. The present work aims to characterize exposure to MF in the 5 Hz to 2 kHz frequency range in a large hospital through both instantaneous environmental measurements and personal monitoring of workers. The study was conducted in different working environments of a hospital with about 4400 employees, many of them working at two or more different work stations and consequently, exposed to MF levels that were expected to be unevenly distributed in space and time. The results indicate that: (1) The dominant frequency at the studied environments was 50 Hz (average 90.8 ± 6% of the total B value); (2) The best descriptive information on a worker's exposure is obtained from personal monitoring of volunteer workers; (3) The arithmetic averages of exposure levels obtained from the monitoring ranged from 0.03 ± 0.01 µT in nurses to 0.39 ± 0.13 µT in physiotherapists; and (4) The description of the MF environment through spot measurements in the workplace, although coherent with the data from personal monitoring, might not adequately estimate MF exposure in some professional categories.