HyClear: A Novel Tissue Clearing Solution for One-Step Clearing of Microtissues.

3-D cell cultures are being increasingly used as in vitro models are capable of better mimicry of in vivo tissues, particularly in drug screenings where mass transfer limitations can affect the cancer biology and response to drugs. Three-dimensional microscopy techniques, such as confocal and multiphoton microscopy, have been used to elucidate data from 3-D cell cultures and whole organs, but their reach inside the 3-D tissues is restrained by the light scattering of the tissues, limiting their effective reach to 100-200 µm, which is simply not enough. Tissue clearing protocols, developed mostly for larger specimens usually involve multiple steps of viscous liquid submersion, and are not easily adaptable for much smaller spheroids and organoids. In this work, we have developed a novel tissue clearing solution tailored for small spheroids and organoids. Our tissue clearing protocol, called HyClear, uses a mixture of DMSO, HPG and urea to allow for one-step tissue clearing of spheroids and organoids, and is compatible with high-throughput screening studies due to its speed and simplicity. We have shown that our tissue clearing agent is superior to many of the commonly used tissue clearing agents and allows for elucidating better quality data from drug screening experiments.

Dosimetric verification of IMRT and 3D conformal treatment delivery using EPID.

PURPOSE: Electronic portal imaging devices (EPIDs) could potentially be useful for either in-vivo or pre-treatment dosimetric verification of external beam radiation therapy. The accuracy of EPID for dosimetric purposes is highly dependent on the specific method used for the determination of dose-response characteristics. The aim of this study was to develop a simple and time-saving EPID back-projection dosimetry algorithm for 2D dose verification in 3D conformal and intensity-modulated beams. METHODS: The procedure of dose reconstruction includes a first calibration step using ionization chamber measurements to convert the Electronic Portal Image (EPI) pixel values into an absorbed dose in water. Subsequently, several corrections were applied to the Portal Dose Images (PDIs) for the effect of field size, attenuator thickness, scattering radiation, beam hardening and EPID off-axis response. Furthermore, to consider tissue inhomogeneity for accurate dose reconstruction, the patient's water equivalent path length (WEPL) was calculated using a range of digitally reconstructed radiographs (DRRs) obtained at various thicknesses by Plastimatch software. The EPID-derived dose maps accuracy was assessed by comparing with the treatment planning system (TPS) calculated dose in the prostate region of Alderson phantom irradiated with 3D conformal and intensity-modulated beams. RESULTS: The gamma analysis for the dose plane showed agreements of 96.95% and 93.5% for 3D conformal and IMRT fields, respectively, with 3%/3 mm acceptance criteria. CONCLUSION: The presented algorithm can provide accurate absolute 2D dose maps for clinical use in the context of 3DCRT or IMRT Quality Assurance (QA) programs.

Planning as Inference in Epidemiological Dynamics Models.

In this work we demonstrate how to automate parts of the infectious disease-control policy-making process via performing inference in existing epidemiological models. The kind of inference tasks undertaken include computing the posterior distribution over controllable, via direct policy-making choices, simulation model parameters that give rise to acceptable disease progression outcomes. Among other things, we illustrate the use of a probabilistic programming language that automates inference in existing simulators. Neither the full capabilities of this tool for automating inference nor its utility for planning is widely disseminated at the current time. Timely gains in understanding about how such simulation-based models and inference automation tools applied in support of policy-making could lead to less economically damaging policy prescriptions, particularly during the current COVID-19 pandemic.

Long-term monitoring in a microfluidic system to study tumour spheroid response to chronic and cycling hypoxia.

We demonstrate the application of a microfluidic platform combining spatiotemporal oxygen control and long-term microscopy monitoring to observe tumour spheroid response to hypoxia. The platform is capable of recreating physiologically-relevant low and cycling oxygen levels not attainable in traditional cell culture environments, while image-based monitoring visualizes cell response to these physiologically-relevant conditions. Monitoring spheroid cultures during hypoxic exposure allows us to observe, for the first time, that spheroids swell and shrink in response to time-varying oxygen profiles switching between 0% and 10% O2; this swelling-shrinkage behaviour appears to be driven by swelling of individual cells within the spheroids. We also apply the system to monitoring tumour models during anticancer treatment under varying oxygen conditions. We observe higher uptake of the anticancer agent doxorubicin under a cycling hypoxia profile than under either chronic hypoxia or in vitro normoxia, and the two-photon microscopy monitoring facilitated by our system also allows us to observe heterogeneity in doxorubicin uptake within spheroids at the single-cell level. Combining optical sectioning microscopy with precise spatiotemporal oxygen control and 3D culture opens the door for a wide range of future studies on microenvironmental mechanisms driving cancer progression and resistance to anticancer therapy. These types of studies could facilitate future improvements in cancer diagnostics and treatment.

Inter-ethnic marriages and severity of coronary artery disease: A multicenter study of Arabian Gulf States.

AIM: To assess the association of inter-ethnic vs intra-ethnic marriage with severity of coronary artery disease (CAD) in men undergoing angiography. METHODS: We conducted a prospective multicenter, multi-ethnic, cross sectional observational study at five hospitals in Saudi Arabia and the United Arab Emirates, in which we used logistic regression analysis with and without adjustment for baseline differences. RESULTS: Data were collected for 1068 enrolled patients undergoing coronary angiography for clinical indications during the period of April 1st, 2013 to March 30th, 2014. Ethnicities of spouses were available only for male patients. Of those enrolled, 687 were married men and constituted the cohort for the present analysis. Intra-ethnic marriages were reported in 70% and inter-ethnic marriages in 30%. After adjusting for baseline differences, inter-ethnic marriage was associated with lower odds of having significant CAD [adjusted odds ratio 0.52 (95%CI: 0.33, 0.81)] or multi-vessel disease (MVD) [adjusted odds ratio 0.57 (95%CI: 0.37, 0.86)]. The adjusted association with left main disease showed a similar trend, but was not statistically significant [adjusted odds ratio 0.74 (95%CI: 0.41, 1.32)]. The association between inter-ethnic marriage and the presence of significant CAD and MVD was not modified by number of concurrent wives (P interaction > 0.05 for both). CONCLUSION: Among married men undergoing coronary angiography, inter-ethnic, as compared to intra-ethnic, marriage is associated with lower odds of significant CAD and MVD.

Socioeconomic Factors and Severity of Coronary Artery Disease in Patients Undergoing Coronary Angiography: A Multicentre Study of Arabian Gulf States.

INTRODUCTION: Coronary artery disease (CAD) is a leading cause of death worldwide. The association of socioeconomic status with CAD is supported by numerous epidemiological studies. Whether such factors also impact the number of diseased coronary vessels and its severity is not well established. MATERIALS AND METHODS: We conducted a prospective multicentre, multi-ethnic, cross sectional observational study of consecutive patients undergoing coronary angiography (CAG) at 5 hospitals in the Kingdom of Saudi Arabia and the United Arab Emirates. Baseline demographics, socioeconomic, and clinical variables were collected for all patients. Significant CAD was defined as ≥70% luminal stenosis in a major epicardial vessel. Left main disease (LMD) was defined as ≥50% stenosis in the left main coronary artery. Multi-vessel disease (MVD) was defined as having >1 significant CAD. RESULTS: Of 1,068 patients (age 59 ± 13, female 28%, diabetes 56%, hypertension 60%, history of CAD 43%), 792 (74%) were from urban and remainder (26%) from rural communities. Patients from rural centres were older (61 ± 12 vs 58 ± 13), and more likely to have a history of diabetes (63 vs 54%), hypertension (74 vs 55%), dyslipidaemia (78 vs 59%), CAD (50 vs 41%) and percutaneous coronary intervention (PCI) (27 vs 21%). The two groups differed significantly in terms of income level, employment status and indication for angiography. After adjusting for baseline differences, patients living in a rural area were more likely to have significant CAD (adjusted OR 2.40 [1.47, 3.97]), MVD (adjusted OR 1.76 [1.18, 2.63]) and LMD (adjusted OR 1.71 [1.04, 2.82]). Higher income was also associated with a higher risk for significant CAD (adjusted OR 6.97 [2.30, 21.09]) and MVD (adjusted OR 2.49 [1.11, 5.56]), while unemployment was associated with a higher risk of significant CAD (adjusted OR 2.21, [1.27, 3.85]). CONCLUSION: Communal and socioeconomic factors are associated with higher odds of significant CAD and MVD in the group of patients referred for CAG. The underpinnings of these associations (e.g. pathophysiologic factors, access to care, and system-wide determinants of quality) require further study.

On-chip clearing of arrays of 3-D cell cultures and micro-tissues.

Three-dimensional (3-D) cell cultures are beneficial models for mimicking the complexities of in vivo tissues, especially in tumour studies where transport limitations can complicate response to cancer drugs. 3-D optical microscopy techniques are less involved than traditional embedding and sectioning, but are impeded by optical scattering properties of the tissues. Confocal and even two-photon microscopy limit sample imaging to approximately 100-200 µm depth, which is insufficient to image hypoxic spheroid cores. Optical clearing methods have permitted high-depth imaging of tissues without physical sectioning, but they are difficult to implement for smaller 3-D cultures due to sample loss in solution exchange. In this work, we demonstrate a microfluidic platform for high-throughput on-chip optical clearing of breast cancer spheroids using the SeeDB, Clear(T2), and ScaleSQ clearing methods. Although all three methods are able to effectively clear the spheroids, we find that SeeDB and ScaleSQ more effectively clear the sample than Clear(T2); however, SeeDB induces green autofluorescence while ScaleS causes sample expansion. Our unique on-chip implementation permits clearing arrays of 3-D cultures using perfusion while monitoring the 3-D cultures throughout the process, enabling visualization of the clearing endpoint as well as monitoring of transient changes that could induce image artefacts. Our microfluidic device is compatible with on-chip 3-D cell culture, permitting the use of on-chip clearing at the endpoint after monitoring the same spheroids during their culture. This on-chip method has the potential to improve readout from 3-D cultures, facilitating their use in cell-based assays for high-content drug screening and other applications.

Core-shell hydrogel beads with extracellular matrix for tumor spheroid formation.

Creating multicellular tumor spheroids is critical for characterizing anticancer treatments since they may provide a better model of the tumor than conventional monolayer culture. Moreover, tumor cell interaction with the extracellular matrix can determine cell organization and behavior. In this work, a microfluidic system was used to form cell-laden core-shell beads which incorporate elements of the extracellular matrix and support the formation of multicellular spheroids. The bead core (comprising a mixture of alginate, collagen, and reconstituted basement membrane, with gelation by temperature control) and shell (comprising alginate hydrogel, with gelation by ionic crosslinking) were simultaneously formed through flow focusing using a cooled flow path into the microfluidic chip. During droplet gelation, the alginate acts as a fast-gelling shell which aids in preventing droplet coalescence and in maintaining spherical droplet geometry during the slower gelation of the collagen and reconstituted basement membrane components as the beads warm up. After droplet gelation, the encapsulated MCF-7 cells proliferated to form uniform spheroids when the beads contained all three components: alginate, collagen, and reconstituted basement membrane. The dose-dependent response of the MCF-7 cell tumor spheroids to two anticancer drugs, docetaxel and tamoxifen, was compared to conventional monolayer culture.

Innovative Methods for the Benefit of Public Health Using Space Technologies for Disaster Response.

Space applications have evolved to play a significant role in disaster relief by providing services including remote sensing imagery for mitigation and disaster damage assessments; satellite communication to provide access to medical services; positioning, navigation, and timing services; and data sharing. Common issues identified in past disaster response and relief efforts include lack of communication, delayed ordering of actions (eg, evacuations), and low levels of preparedness by authorities during and after disasters. We briefly summarize the Space for Health (S4H) Team Project, which was prepared during the Space Studies Program 2014 within the International Space University. The S4H Project aimed to improve the way space assets and experiences are used in support of public health during disaster relief efforts. We recommend an integrated solution based on nano-satellites or a balloon communication system, mobile self-contained relief units, portable medical scanning devices, and micro-unmanned vehicles that could revolutionize disaster relief and disrupt different markets. The recommended new system of coordination and communication using space assets to support public health during disaster relief efforts is feasible. Nevertheless, further actions should be taken by governments and organizations in collaboration with the private sector to design, test, and implement this system.

Assessment of atrazine distribution in Shiraz soils, south of Iran.

The main objective of this study was focused on determining atrazine residual concentration in agricultural soil in Shiraz and its vicinity. Twenty two sampling fields were selected by grid sampling in Shiraz and its vicinity. Atrazine residual concentrations in 0-20, 20-40 and 40-60 cm soil depths were in the range of 15-550 microg kg(-1) soil. Data showed that the concentration of atrazine did not exceed the soil quality standard for agriculture which is 22 mg kg(-1) soil and there was no significant difference between depth and atrazine residual concentration (p > 0.05). Although, in all sampling regions in Shiraz and its vicinity, the concentration of atrazine did not exceed the soil quality standard for agriculture, atrazine leaching and dissipation rate in soil and risk of atrazine ground water pollution must be determined.

Using irradiation treatment for reduction of anaerobic bacteria from a wastewater treatment plant.

This study was done to investigate the reduction of anaerobic bacteria (Clostridium perfringens) by ultrasound irradiation technology (USI). C. perfringens is the most important of the sulfite-reducing clostridia and is normally present in human and animal feces. Clostridial spores survive longer than coliforms, Escherichia coli or enterococci, and are consequently used as an indicator of past fecal pollution. The spores are not always inactivated by chlorination, but are not a hazard to health in potable water. C. perfringens are very resistant to chlorine and other drinking-water disinfectants. Conventional water treatment practices including chlorination are sometimes inadequate for inactivation of C. perfringens. Ultrasound irradiation is able to inactive C. perfringens through a number of physical and chemical effects arising from acoustic cavitation. The phenomenon of cavitation, which involves formation, growth, and violent collapse of vapour bubbles in a liquid media, is known to generate a high-intensity pressure, which affects the cell and C. perfringens' viability. Cavitations disrupt C. perfringens. Ultrasound irradiation at a frequency of 42 kHz was used to expose aqueous suspension of C. perfringens to evaluate the disinfection efficacy of ultrasound irradiation. Results indicated a significant increase in reduction of C. perfringens with increasing ultrasound time. C. perfringens was inactivated by 99.98% after 90 min.

Isolation and identification of atrazine-degrading bacteria from corn field soil in Fars province of Iran.

In this study several agricultural fields with a long history of atrazine application in Fars province of Iran have been explored for their potential of atrazine biodegradation. After several subculturing for a period of 300 days acclimation, leads to an enhancement of atrazine biodegradation rate. A successful enrichment culture with a high capability for atrazine degradation was obtained (88%). A combination of enrichment culture technique, in a basal salt medium containing atrazine and carbon sources under nitrogen limitation and plating on indicator atrazine agar, have permitted the isolation of bacterial consortium with high capability of using atrazine as a nitrogen source. Seven gram-negative and one gram-positive bacterial strain, which were able to use this herbicide as a sole source of nitrogen, were isolated from Darehasalouie Kavar corn field soil. Based on physiological, biochemical and nutritional characteristics, the isolated bacteria were identified as Pseudomonas alcaligenes, Acidovorax sp., Pseudomonas putida, Ralstonia eutrophus, Pseudomonas syiringe, Erwinia tracheiphila, Entrobacter agglomerans and Micrococcus varians. Therefore, the bacterial consortium in liquid culture containing carbon sources and atrazine as a sole source of nitrogen, degrade added atrazine more than 80%.

Study of natural organic matter fractions in water sources of Tehran.

Natural Organic Matters (NOMs) are abundant in natural water resources and in many ways may affect the unit operations in water treatment. Although, NOMs are considered harmless but they have been recognized disinfection by-products precursors (DBP(s)) during the chlorination process. Formation of DBP(s) highly depends on the composition and concentration of NOM, which can be broadly divided into two fractions of hydrophobic (humic) and hydrophilic (non-humic) substances. The objective of this study was to determine Natural organic matter and its fractions concentration in the surface water sources of Tehran. Water sampling was conducted monthly between May to July 2006 in three rivers Lar, Jajrood and Karaj as the main drinking water supplying sources in Tehran. Quantitative parameters of pH, EC, UV254 and DOC were studied based on to standard methods. The XAD-7 resin method was used for fractionation of NOM. Results showed that NOM concentrations in Lar, Jajrood and Karaj rivers were 8.53, 12.9 and 11.3 mg L(-1), respectively. The HPO (hydrophobic) fraction was predominant compared to the HPI (hydrophilic) fraction in the all of water samples. The mean of total percent of HPO and HPI fractions were about 57 and 43%, respectively. Since the hydrophobic NOM fraction exhibits higher trihalomethane formation potential (THMFP) than hydrophilic NOM, Tehran water chlorination exhibits higher THMFP than haloacetic acid formation potential (HAAFP). The information obtained from this study may be further employed in the design of the control technique and management strategies for the water treatment plant, especially for DBP(s) reduction.

The treatment of wastewater containing crude oil with aerated submerged fixed-film reactor.

An aerated submerged fixed-film (ASFF) bioreactor was developed to treat an artificial wastewater based on crude oil. Bee-Cell 2000 was used as support media having porosity of 87% and a specific surface area of 650 m2 m(-3). The system was able to achieve 70.87-93.12% removal efficiencies of Chemical Oxygen Demand (COD) in the organic loading rate range of 1.310 to 15.797 g COD m(-2) day(-1). Data gained exhibited that the effluent COD concentration ranged between 68.68 and 292.60 mg L(-1) at organic loadings experienced. Therefore, an ASFF process showed that it was feasible to treat high oily wastewater in order to meet the discharge standards.

Clomiphene citrate in the twenty-first century.

Clomiphene citrate is the drug most commonly prescribed for ovulation induction. It is the first choice medication in normogonadotrophic oligo/amenorrhoeic infertility (WHO group 2), essentially associated with polycystic ovaries. Anovulatory women who are responsive to clomiphene citrate should be treated for at least six cycles and the treatment should probably be limited to a maximum of 12 cycles. It is necessary to monitor at least the first cycle with ultrasonography because of the risk of multiple pregnancy and the variable response of patients to different doses of clomiphene. In addition, the risk of ovarian hyperstimulation syndrome should not be underestimated. More triplets and higher order pregnancies result from ovulation induction than from in vitro fertilization, and multiple pregnancy has many risks for both mother and babies. The role of empirical clomiphene in the treatment of unexplained infertility is debatable and the present data are inconclusive. Obesity, hyperandrogenaemia and insulin resistance are important factors in clomiphene-resistant patients. Failure to ovulate in response to clomiphene has been approached by either medical or surgical treatment. An effective alternative medical treatment is gonadotrophin injections. Treatment with metformin and the new generation of insulin-sensitizing drugs is under evaluation. The most widely used surgical treatment today is laparoscopic ovarian drilling, which appears to be as effective as gonadotrophin therapy.

Endoscopic transnasal pituitary surgery: report on 180 cases.

The endoscopic transnasal approach is an evolving technique for treating lesions in the sella turcica. Since this method was introduced at our institution 4 years ago, the majority of transsphenoidal procedures are performed with it. The records of all patients having endoscopic transnasal hypophysectomy at the Mayo Clinic during the last 4 years were reviewed retrospectively. The criteria analyzed were safety, functional and cosmetic outcome, and complications. During the 4-year period, the operative procedure was modified to improve operative exposure and safety. The results of our review showed a significant decrease in length of hospital stay, reduced operative time, reduced need for nasal packing, and elimination of a sublabial incision. The complication rate was equivalent to that reported for the traditional transseptal transsphenoidal approach. As the neurosurgeons at our institution gained experience with this approach, an increasing number of pituitary microadenomas were resected safely and successfully. In addition, because of the limited septal dissection, this approach is particularly helpful for revision operations. This approach also can be used for the full range of pituitary lesions and in conjunction with adjunctive techniques, including frontal craniotomy and gamma-knife irradiation. Currently, the endoscopic transsphenoidal approach is the method preferred for surgically treating pituitary lesions in adults at our institution.

Anergy in peripheral memory CD4(+) T cells induced by low avidity engagement of T cell receptor.

Induction of tolerance in self-reactive memory T cells is an important process in the prevention of autoimmune responses against peripheral self-antigens in autoimmune diseases. Although naive T cells can readily be tolerized, memory T cells are less susceptible to tolerance induction. Recently, we demonstrated that low avidity engagement of T cell receptor (TCR) by low densities of agonist peptides induced anergy in T cell clones. Since memory T cells are more responsive to lower antigenic stimulation, we hypothesized that a low avidity TCR engagement may induce tolerance in memory T cells. We have explored two antigenic systems in two transgenic mouse models, and have tracked specific T cells that are primed and show memory phenotype. We demonstrate that memory CD4(+) T cells can be rendered anergic by presentation of low densities of agonist peptide-major histocompatibility complex complexes in vivo. We rule out other commonly accepted mechanisms for induction of T cell tolerance in vivo, such as deletion, ignorance, or immunosuppression. Anergy is the most likely mechanism because addition of interleukin 2-reversed anergy in specific T cells. Moreover, cytotoxic T lymphocyte antigen (CTLA)-4 plays a critical role in the induction of anergy because we observed that there was increased surface expression of CTLA-4 on anergized T cells, and that injection of anti-CTLA-4 blocking antibody restored anergy in vivo.

HLA-DM recognizes the flexible conformation of major histocompatibility complex class II.

DM facilitates formation of high affinity complexes of peptide-major histocompatibility complex (MHC) by release of class II MHC-associated invariant chain peptide (CLIP). This has been proposed to occur through discrimination of complex stability. By probing kinetic and conformational intermediates of the wild-type and mutant human histocompatibility leukocyte antigen (HLA)-DR1-peptide complexes, and examining their reactivities with DM, we propose that DM interacts with the flexible hydrophobic pocket 1 of DR1 and converts the molecule into a conformation that is highly peptide receptive. A more rigid conformation, generated upon filling of pocket 1, is less susceptible to DM effects. Thus, DM edits peptide-MHC by recognition of the flexibility rather than stability of the complex.