The “Sharp” blade against HIF-mediated metastasis

Hypoxia-inducible factors (HIFs) control cellular adaptation to oxygen deprivation. Cancer cells engage HIFs to sustain their growth in adverse conditions, thus promoting a cellular reprograming that includes metabolism, proliferation, survival and mobility. HIFs overexpression in human cancer biopsies correlates with high metastasis and mortality. A recent report has elucidated a novel mechanism for HIFs regulation in triple-negative breast cancer. Specifically, the basic helix-loop-helix (bHLH), Sharp-1, serves HIF1α to the proteasome and promotes its O₂-indendpendet degradation, counteracting HIF-mediated metastasis. These findings shed light on how HIFs are manipulated during cancer pathogenesis.     

Does Antibiotic Resistance Evolve in Hospitals?

Nosocomial outbreaks of bacteria are well documented. Based on these incidents, and the heavy usage of antibiotics in hospitals, it has been assumed that antibiotic resistance evolves in hospital environments. To test this assumption, we studied resistance phenotypes of bacteria collected from patient isolates at a community hospital over a 2.5-year period. A graphical model analysis shows no association between resistance and patient information other than time of arrival. This allows us to focus on time-course data. We introduce a hospital transmission model, based on negative binomial delay. Our main contribution is a statistical hypothesis test called the Nosocomial Evolution of Resistance Detector (NERD). It calculates the significance of resistance trends occurring in a hospital. It can inform hospital staff about the effects of various practices and interventions, can help detect clonal outbreaks, and is available as an R package. We applied the NERD method to each of the 16 antibiotics in the study via 16 hypothesis tests. For 13 of the antibiotics, we found that the hospital environment had no significant effect on the evolution of resistance; the hospital is merely a piece of the larger picture. The p-values obtained for the other three antibiotics (cefepime, ceftazidime, and gentamicin) indicate that particular care should be taken in hospital practices with these antibiotics. One of the three, ceftazidime, was significant after accounting for multiple hypotheses, indicating a trend of decreased resistance for this drug.     

Do Pediatric Hospitals Improve Operative Efficiency?

BackgroundIn recent years there has been a push towards developing free standing pediatric facilities to provide care specifically towards pediatric patients. The purpose of this study was to determine if moving pediatric cases from a general hospital to a dedicated pediatric facility improved the quality and efficiency of surgical procedures.MethodsA retrospective review of pediatric patients undergoing posterior spinal fusion (PSF) was performed. All procedures were performed by one orthopaedic surgeon (SLW) from 2015 to 2019. The procedures were performed at a general hospital (GH) the first two years, and at a pediatric hospital (PH) the subsequent years. Data extracted included patient sex, age, and procedure type as well as procedure duration, operative turnover time, hospital length of stay, transfusion requirements, and operative delay. Exclusively pediatric adolescent idiopathic scoliosis (AIS) patients undergoing PSF were included due to the high volume and consistent surgical procedures therefore limiting confounding variables.ResultsA total of five hundred PSF pediatric procedures were performed during the time period. After excluding non-adolescent idiopathic scoliosis cases, a total of 208 procedures were reviewed (105 at GH; 103 at PH). There was no statistical difference between the groups in regards to operative time (GH: 200 min, PH: 200 min; p=0.91), room turnover time (GH: 38 min, PH: 38 min; p=0.801), or rate of transfusion (GH: 20% PH: 30%; p=0.09). Length of stay was significantly shorter in the PH cohort compared to the GH cohort (4.35 vs. 3.84 days, p=0.0001). However, a smaller proportion of cases at the PH started on time compared to the GH (34% vs. 58%; p=0.0005).ConclusionOverall, this study demonstrated that AIS procedures at the PH did show a statistically significant reduction in hospital length of stay. However, timely start of the procedure was less likely at this particular facility. Level of Evidence: III     

“Oncogenic Shock”: Turning an Activated Kinase against the Tumor Cell

Accumulating evidence indicates that mutationally activated kinases are especially good targets for anti-cancer drugs. It has been suggested that this reflects a state of “oncogene addiction” of tumor cells. We recently reported experimental studies that may provide a molecular mechanism to explain such apparent dependency. We find that oncogenic kinases produce both pro-survival and pro-apoptotic signals that decay at different rates upon oncogene inactivation. Pro-survival signals are rapidly attenuated, whereas pro-apoptotic signals are relatively longer-lived. This differential signal decay creates a temporal window during which pro-apoptotic outputs from the oncogenic kinase predominate to actively promote tumor cell death upon kinase inhibition. We refer to this mechanism as “oncogenic shock”, and suggest that it has significant implications for the optimal therapeutic use of targeted kinase inhibitors.     

Immunity against prions?

Several recent reports indicate that antibodies directed against the cellular form of the prion protein, PrP^C, might eliminate the transmissible agent of spongiform encephalopathies (the prion) from scrapie-infected cells in vitro, and that a humoral immune response could prevent scrapie pathogenesis in vivo. These findings suggest that immunotherapeutical intervention against prion diseases is not unattainable. Will vaccines and post-exposure strategies based on antibodies ever prove useful against scrapie, bovine spongiform encephalopathy (BSE), or Creutzfeldt–Jakob disease?     

The Compound Chinese Medicine “Kang Fu Ling” Protects against High Power Microwave-Induced Myocardial Injury

Background

The prevention and treatment of Microwave-caused cardiovascular injury remains elusive. This study investigated the cardiovascular protective effects of compound Chinese medicine “Kang Fu Ling” (KFL) against high power microwave (HPM)-induced myocardial injury and the role of the mitochondrial permeability transition pore (mPTP) opening in KFL protection.

Methods

Male Wistar rats (100) were divided into 5 equal groups: no treatment, radiation only, or radiation followed by treatment with KFL at 0.75, 1.5, or 3 g/kg/day. Electrocardiography was used to Electrophysiological examination. Histological and ultrastructural changes in heart tissue and isolated mitochondria were observed by light microscope and electron microscopy. mPTP opening and mitochondrial membrane potential were detected by confocal laser scanning microscopy and fluorescence analysis. Connexin-43 (Cx-43) and endothelial nitric oxide synthase (eNOS) were detected by immunohistochemistry. The expression of voltage-dependent anion channel (VDAC) was detected by western blotting.

Results

At 7 days after radiation, rats without KFL treatment showed a significantly lower heart rate (P<0.01) than untreated controls and a J point shift. Myocyte swelling and rearrangement were evident. Mitochondria exhibited rupture, and decreased fluorescence intensity, suggesting opening of mPTP and a consequent reduction in mitochondrial membrane potential. After treatment with 1.5 g/kg/day KFL for 7 d, the heart rate increased significantly (P<0.01), and the J point shift was reduced flavorfully (P<0.05) compared to untreated, irradiated rats; myocytes and mitochondria were of normal morphology. The fluorescence intensities of dye-treated mitochondria were also increased, suggesting inhibition of mPTP opening and preservation of the mitochondrial membrane potential. The microwave-induced decrease of Cx-43 and VDAC protein expression was significantly reversed.

Conclusion

Microwave radiation can cause electrophysiological, histological and ultrastructural changes in the heart. KFL at 1.5 g/kg/day had the greatest protective effect on these cardiovascular events. mPTP plays an important role in the protective effects of KFL against microwave-radiation-induced myocardial injury.     

Cytotoxic activity of doxorubicin “loaded” neutrophils against human mammary carcinoma (HTB-19)

Neutrophils were intra-cellularly “loaded” with the chemotherapeutic agent, doxorubicin applying a variety of incubation conditions in order to identify parameters which maximize chemotherapeutic incorporation, while simultaneously preserving optimal viability and chemotactic responsiveness. Doxorubicin “loaded” neutrophils (DLN) were produced in triplicate at different combinations of incubation conditions such as temperature (4° C, 37° C); duration (0, 1, 2 hours); and doxorubicin concentration (20, 40, 60μg/ml). Chemotactic responsiveness of rinsed DLN preparations was subsequently assessed against the neutrophil peptide chemotactic agent, formyl methionyl leucyl phenylalanine (fMLP, 10⁻⁶ M) utilizing a modified 96-well Boyden chemotactic chamber apparatus. Viable, fMLP-responsive DLN preparations were subsequently detected with MTT vitality staining reagent. At sub-physiological incubation temperatures (4° C), profound declines in the viability of DLN preparations were detected when simultaneously incubated with doxorubicin formulated at concentrations greater than 10μg/ml. In contrast, DLN preparations incubated at 37° C displayed diminished viability only when incubated with doxorubicin formulated at a concentration of 60μg/ml. Viable DLN populations were subsequently evaluated to determine their ability to exertin vitro cytotoxic activity against monolayer populations of human mammary carcinoma (HTB-19) propagated in a tissue culture environment. The lethal effect which DLN preparations inflicted towards HTB-19 populations was substantially greater than was observed with an equivalent population of untreated neutrophils. Maximalin vitro cytotoxic activity was detected with DLN preparations produced at 37° C in the presence of doxorubicin formulated at a concentration of 40μg/ml. In contrast, DLN preparations produced at an incubation temperature of 37° C, and a doxorubicin concentration of 20μg/ml displayed relatively lower levels ofin vitro cytotoxic activity against HTB-19 monolayer populations. The degree ofin vitro cytotoxic activity exerted against HTB-19 monolayer populations by DLN preparations was directly influenced by the duration of the challenge period. Maximalin vitro cytotoxic activity was observed when HTB-19 monolayer populations were challenged with DLN preparations for a period of 96-hours duration at 37° C. Challenge periods of 48-hours duration produced levels ofin vitro cytotoxic activity which were substantially lower than those observed for challenge periods of 96-hours duration. Optimalin vitro cytotoxic activity was recognized when DLN preparations were allowed to establish direct contact with HTB-19 monolayer populations at an estimated DLN:HTB-19 cellular ratio of approximately 5:1 (37° C, CO₂, 6%). Significantly lessin vitro cytotoxic activity was recognized when DLN preparations were only permitted indirect cellular contact with HTB-19 monolayer populations which was achieved through the application of a semi-permeable 3μM pore membrane partition. In vitro cytotoxic activity of DLN populations was not inhibited by the anti-oxidant agent, dimethyl sulfoxide (DMSO), but was inhibited in the presence of glutathione (GSH), superoxide dismutase (SOD), and vitamin E (α-tocopherol). Similarly,in vitro cytotoxic activity of DLN populations was also inhibited in the presence of sodium heparin (serine esterase inhibitor), and dexamethasone (inhibitor of neutrophil activation-degranulation phenomenon). Experimental results observed in these investigations collectively imply that thein vitro cytotoxic activity exerted by DLN preparations against HTB-19 populations is in part attributable to neutrophil-mediated cytotoxic immunity. This innate property of neutrophil populations involves their capacity to generate highly reactive oxygen “free” radical species (O₂, HO, H₂O₂), and synthesize degradative proteolytic enzyme fractions. These endogenous substances are intimately involved in the processes of neutrophil-mediated cytotoxic immunity when “released” into the extracellular milieu and may potentially act in concert with the anti-neoplastic properties of chemotherapeutic agents such as doxorubicin.     

Plant Remedies against Witches and the Evil Eye in a Spanish “Witches’ Village”

Plant Remedies against Witches and the Evil Eye in a Spanish “Witches’ Village.” An ethnobotanical survey was carried out to understand the traditional knowledge and current use of different preventive and curative plant remedies against witches and the evil eye in a Spanish rural community (Villarino de los Aires, Salamanca). Located in a Spanish region known as “Arribes del Duero,” this locality has historically been considered an important “witches’ village.” An anonymous questionnaire was answered by 52 people living in the village. The cultural importance index (CI) of each species was calculated. To analyze how knowledge varies as a function of the socio-demographic characteristics of the different informants, an analysis of covariance (ANCOVA) was performed, taking as variable to model the use-reports provided, and as explanatory variables the age, gender, and educational status. Age was the only variable that explained the variety in the number of plant remedies known; people over 60 knew significantly more plant remedies. Fifteen vascular plants were mentioned. The preventive remedies were particularly associated with key moments of the religious calendar. Branches gathered from olive trees, laurel, and/or rosemary are blessed on Palm Sunday, and then placed on window sills to protect people’s homes. During the celebration of Saint John’s Bonfire, aromatic plants are burnt, and the purifying and protecting power of the smoke emerges. The traditional use of plants hung behind doors of houses and stables to repel witches, and rituals for curing evil eye affecting people, animals, or even possessions were also revealed. Even today in rural communities of western Spain, there is a clear connection between popular religious and magic beliefs and their relationship with nature, especially plants.