Case report: Sagliker syndrome in the patient with recurrent tertiary hyperparathyroidism due to intrathyroidal parathyroid carcinoma

Sagliker syndrome (SS) is an extremely rare disorder that manifests in patients with advanced chronic kidney disease (CKD) undergoing programmed hemodialysis as a renal replacement therapy. Treatment of secondary hyperparathyroidism (SHPT) in these patients is still challenging. The main clinical manifestations of SS include craniofacial and fingertip deformities, dental anomalies, gingival hyperplasia, short stature, hearing loss, neurological and psychiatric impairment. The etiology and pathogenesis of SS in patients with SHPT require further clarification. However, mutations in the GNAS1, FGF23, and FGFR3 genes were described in some patients, suggesting a possible role of genetic predisposition to the syndrome. The preferred therapeutic approach for SS is surgery, but the volume of the operation is debated. The main surgical strategies include total, subtotal parathyroidectomy, or total parathyroidectomy with autotransplantation of the parathyroid gland (PG). Unfortunately, parathyroidectomy does not contribute to the regression of significant skeletal deformities. We present a unique clinical case of a patient with classical features of SS, recurrent tertiary hyperparathyroidism (THPT) after total parathyroidectomy due to intrathyroidal parathyroid carcinoma (PC).

Drug repositioning strategy for the identification of novel telomere-damaging agents: A role for NAMPT inhibitors

Drug repositioning strategy represents a valid tool to accelerate the pharmacological development through the identification of new applications for already existing compounds. In this view, we aimed at discovering molecules able to trigger telomere-localized DNA damage and tumor cell death. By applying an automated high-content spinning-disk microscopy, we performed a screening aimed at identifying, on a library of 527 drugs, molecules able to negatively affect the expression of TRF2, a key protein in telomere maintenance. FK866, resulting from the screening as the best candidate hit, was then validated at biochemical and molecular levels and the mechanism underlying its activity in telomere deprotection was elucidated both in vitro and in vivo. The results of this study allow us to discover a novel role of FK866 in promoting, through the production of reactive oxygen species, telomere loss and deprotection, two events leading to an accumulation of DNA damage and tumor cell death. The ability of FK866 to induce telomere damage and apoptosis was also demonstrated in advanced preclinical models evidencing the antitumoral activity of FK866 in triple-negative breast cancer-a particularly aggressive breast cancer subtype still orphan of targeted therapies and characterized by high expression levels of both NAMPT and TRF2. Overall, our findings pave the way to the development of novel anticancer strategies to counteract triple-negative breast cancer, based on the use of telomere deprotecting agents, including NAMPT inhibitors, that would rapidly progress from bench to bedside.

Intraoperative Assessment of Breast Cancer Tissues after Breast-Conserving Surgery Based on Mapping the Attenuation Coefficients in 3D Cross-Polarization Optical Coherence Tomography

Intraoperative differentiation of tumorous from non-tumorous tissue can help in the assessment of resection margins in breast cancer and its response to therapy and, potentially, reduce the incidence of tumor recurrence. In this study, the calculation of the attenuation coefficient and its color-coded 2D distribution was performed for different breast cancer subtypes using spectral-domain CP OCT. A total of 68 freshly excised human breast specimens containing tumorous and surrounding non-tumorous tissues after BCS was studied. Immediately after obtaining structural 3D CP OCT images, en face color-coded attenuation coefficient maps were built in co-(Att(co)) and cross-(Att(cross)) polarization channels using a depth-resolved approach to calculating the values in each A-scan. We determined spatially localized signal attenuation in both channels and reported ranges of attenuation coefficients to five selected breast tissue regions (adipose tissue, non-tumorous fibrous connective tissue, hyalinized tumor stroma, low-density tumor cells in the fibrotic tumor stroma and high-density clusters of tumor cells). The Att(cross) coefficient exhibited a stronger gain contrast of studied tissues compared to the Att(co) coefficient (i.e., conventional attenuation coefficient) and, therefore, allowed improved differentiation of all breast tissue types. It has been shown that color-coded attenuation coefficient maps may be used to detect inter- and intra-tumor heterogeneity of various breast cancer subtypes as well as to assess the effectiveness of therapy. For the first time, the optimal threshold values of the attenuation coefficients to differentiate tumorous from non-tumorous breast tissues were determined. Diagnostic testing values for Att(cross) coefficient were higher for differentiation of tumor cell areas and tumor stroma from non-tumorous fibrous connective tissue: diagnostic accuracy was 91-99%, sensitivity-96-98%, and specificity-87-99%. Att(co) coefficient is more suitable for the differentiation of tumor cell areas from adipose tissue: diagnostic accuracy was 83%, sensitivity-84%, and specificity-84%. Therefore, the present study provides a new diagnostic approach to the differentiation of breast cancer tissue types based on the assessment of the attenuation coefficient from real-time CP OCT data and has the potential to be used for further rapid and accurate intraoperative assessment of the resection margins during BCS.

Box-Behnken assisted development and validation of high-performance liquid chromatography method for the simultaneous determination of doxorubicin and vorinostat in polymeric nanoparticles

While histone deacetylase inhibitors, such as vorinostat, demonstrate a significant effect against hematological cancers, their application for solid tumor treatment is limited. However, there is strong evidence that combinatorial administration of vorinostat and genotoxic agents (e.g., doxorubicin) enhances the antitumoral action of both drugs against tumors. We developed a high-performance liquid chromatography method for the simultaneous determination of doxorubicin and vorinostat in polymeric nanoparticles designed to provide the parenteral administration of both drugs and increase their safety profile. We performed separation on Nucleodur C-18 Gravity column with a mixture of 10 mM potassium dihydrogen phosphate buffer pH 3.9:ACN (90:10 v/v) as mobile phase at 240 nm. The method was linear within the concentration range of 4.2-52.0 μg/ml for both drugs with limits of detection and quantification of 3.5 and 10.7 μg/ml for doxorubicin and 2.5 and 7.7 μg/ml for vorinostat, respectively. The method was precise and accurate over the concentration range of analysis. Drug loading was 5.4% for doxorubicin and 0.8% for vorinostat. Degradation of doxorubicin after irradiation was less than 5%, while the amount of vorinostat decreased at 88% under the same conditions. Thus, the validated method could be adopted for routine simultaneous analysis of doxorubicin and vorinostat in polymeric nanoparticles.

A combined use of silver pretreatment and impregnation with consequent Nissl staining for cortex and striatum architectonics study

Despite a rapid growth in the application of modern techniques for visualization studies in life sciences, the classical methods of histological examination are yet to be outdated. Herein, we introduce a new approach that involves combining silver nitrate pretreatment and impregnation with consequent Nissl (cresyl violet) staining for cortex and striatum architectonics study on the same microscopy slide. The developed approach of hybrid staining provides a high-quality visualization of cellular and subcellular structures, including impregnated neurons (about 10%), Nissl-stained neurons (all the remaining ones), and astrocytes, as well as chromatophilic substances, nucleoli, and neuropil in paraffin sections. We provide a comparative study of the neuronal architectonics in both the motor cortex and striatum based on the differences in their tinctorial properties. In addition to a comparative study of the neuronal architectonics in both the motor cortex and striatum, the traditional methods to stain the cortex (motor and piriform) and the striatum are considered. The proposed staining approach compiles the routine conventional methods for thin sections, expanding avenues for more advanced examination of neurons, blood–brain barrier components, and fibers both under normal and pathological conditions. One of the main hallmarks of our method is the ability to detect changes in the number of glial cells. The results of astrocyte visualization in the motor cortex obtained by the developed technique agree well with the alternative studies by glial fibrillary acidic protein (GFAP) immunohistochemical reaction. The presented approach of combined staining has great potential in current histological practice, in particular for the evaluation of several neurological disorders in clinical, pre-clinical, or neurobiological animal studies.

Memristor Degradation Analysis Using Auxiliary Volt-Ampere Characteristics

The memristor is one of the modern microelectronics key devices. Due to the nanometer scale and complex processes physic, the development of memristor state study approaches faces limitations of classical methods to observe the processes. We propose a new approach to investigate the degradation of six Ni/Si₃N₄/p+Si-based memristors up to their failure. The basis of the proposed idea is the joint analysis of resistance change curves with the volt-ampere characteristics registered by the auxiliary signal. The paper considers the existence of stable switching regions of the high-resistance state and their interpretation as stable states in which the device evolves. The stable regions' volt-ampere characteristics were simulated using a compact mobility modification model and a first-presented target function to solve the optimization problem.

Treatment challenges and health conditions among people living with HIV with or without substance use disorder in the Russian Federation

We quantified treatment challenges faced by people living with HIV (PLHIV) in Russia. Cross-sectional data of 150 PLHIV in Russia were from the 2019 Positive Perspectives Survey. Mean age was 38.3 y. Two-thirds (68.0%[102/150]) had ever disguised their HIV pills, and 43.3%[65/150] said they would be stressed if someone saw their HIV pills. Overall, 14.7%[22/150] reported being ever diagnosed with substance use disorder (SUD). Self-rated optimal health was significantly lower among those with vs without a report of SUD on multiple health domains: sexual (40.9%[9/22] vs. 70.3%[90/128], p = 0.007), physical (22.7%[5/22] vs. 68.0%[87/128], p < 0.001), and overall health (27.3%[6/22] vs. 68.8%[88/128], p < 0.001). Those reporting SUD were more likely to miss HIV medication ≥ 1 time in the past month because they used recreational drugs (age and gender-adjusted prevalence ratio [APR] = 8.23, 95%CI = 6.99-9.68), could not afford their medication (APR = 3.28, 95%CI = 2.90-3.72), had to work (APR = 3.27, 95%CI = 2.97-3.60), or to avoid side effects (APR = 2.62, 95%CI = 2.37-2.89). Furthermore, self-reported SUD was strongly associated with numerous poor health conditions, including self-reported diagnosis of cancer (APR = 6.67, 95%CI = 5.24-8.48), mental illness (APR = 5.01, 95%CI = 4.53-5.55), and liver disease (APR = 4.29, 95%CI = 3.98-4.61). The distinct patterns of poorer health-related outcomes among PLHIV with SUD underscore the need to address behavioral and psychosocial challenges as part of holistic HIV care.

Zeboid cow milk: physicochemical quality indicator

Introduction. A herd of zeboid cattle was created by the Snegiri Scientific and Experimental Farm (Moscow region, Russia) as a result of long-term selection and crossbreeding zebu (Bos indicus L.) with cattle (Bos taurus L.). These hybrid cows have good physiological parameters, high resistance to diseases, and a significant adaptive potential. The quality of milk produced by zebu cows at different lactation and milking times has not been studied as well as their milking capacity. Therefore, we aimed to assess the variability of specific physicochemical indicators of milk produced by Snegiri’s zeboid dairy herd. Study objects and methods. The milk of 193 zeboid cows (6–12% of zebu blood) from the Snegiri Farm was analyzed by standard methods for quality indicators such as fat, nonfat milk solids, density, bound water, freezing point, protein, and lactose. Then, we determined how these indicators changed depending on the lactation number and the time of milking (morning/evening). Statistical analysis was applied to process the data. Results and discussion. Such indicators as nonfat milk solids, density, bound water, freezing point, protein, and lactose of zeboid cow milk were consistent with the normal indicators for raw cow’s milk. Only its fat content (4.39%) exceeded the norm. We found no correlation between the quality of milk and the number of lactations. However, the evening milk was more concentrated, with a significant increase in nonfat milk solids and density, as well as with a lower freezing point. Conclusion. Zeboid cows, which can be bred in suboptimal conditions, produce milk suitable for dairy products since it has a high fat content regardless of lactation and milking time.

Impairments of cerebral blood flow microcirculation in rats brought on by cardiac cessation and respiratory arrest

The impairments of cerebral blood flow microcirculation brought on by cardiac and respiratory arrest were assessed with multi-modal diagnostic facilities, utilising laser speckle contrast imaging, fluorescence spectroscopy and diffuse reflectance spectroscopy. The results of laser speckle contrast imaging show a notable reduction of cerebral blood flow in small and medium size vessels during a few minutes of respiratory arrest, while the same effect was observed in large sinuses and their branches during the circulatory cessation. Concurrently, the redox ratio assessed with fluorescence spectroscopy indicates progressing hypoxia, NADH accumulation and increase of FAD consumption. The results of diffuse reflectance spectra measurements display a more rapid grow of the perfusion of deoxygenated blood in case of circulatory impairment. In addition, consequent histopathological analysis performed by using new tissue staining procedure developed in-house. It shows notably higher reduction of size of the neurons due to their wrinkling within brain tissues influenced by circulation impair. Whereas, the brain tissues altered with the respiratory arrest demonstrate focal perivascular oedema and mild hypoxic changes of neuronal morphology. Thus, the study suggests that consequences of a cessation of cerebral blood flow become more dramatic and dangerous compare to respiratory arrest.

Coherent X-ray beam expander based on a multilens interferometer

A coherent X-ray beam expander based on a multilens interferometer is proposed in this paper. The multilens interferometer allows efficient generation of a highly diverging coherent beam up to several milliradians in the hard X-ray energy range. The optical properties of the interferometer were experimentally demonstrated at the ESRF ID13 undulator beamline (Grenoble, France), using 12.4 keV X-rays. The beam expander allowed us to control the angular size and photon flux density of the formed beam and enabled operation in both coherent and incoherent modes. The experimental results were fully consistent with the theoretical concepts and appropriate computer simulations. Future design improvements and related applications are also discussed.

The influence of the Sc3+ dopant on the transmittance of (Y, Er)3Al5O12 ceramics

High erbium content yttrium aluminum garnet (Er:YAG) and yttrium scandium aluminum garnet (Er:YSAG) ceramics have been fabricated from Er:YAG and Er:YSAG powders, respectively. The powders have been synthesized via a reverse precipitation technique, processed by uniaxial pressing followed by cold isostatic pressing, and sintered in a vacuum. TEOS (tetraethoxysilane) was used as a sintering additive. After vacuum sintering, all of the samples were processed by annealing in air to increase the transmittance and polished on both sides. The influence of the Sc³⁺ content and the synthesis conditions on the microstructure and optical transparency of the Er:YAG and Er:YSAG ceramics have been investigated in detail. It has been found that changing Al³⁺ for the bigger Sc³⁺ ion leads to the transmittance increasing to up to 60% at a wavelength of about 1500 nm.

Emergency clinicians' knowledge, preparedness and experiences of managing COVID-19 during the 2020 global pandemic in Australian healthcare settings

BACKGROUND

Emergency clinicians have a crucial role during public health emergencies and have been at the frontline during the COVID-19 pandemic. This study examined the knowledge, preparedness and experiences of Australian emergency nurses, emergency physicians and paramedics in managing COVID-19.

METHODS

A voluntary cross-sectional study of members of the College of Emergency Nursing Australasia, the Australasian College for Emergency Medicine, and the Australasian College of Paramedicine was conducted using an online survey (June-September 2020).

RESULTS

Of the 159 emergency nurses, 110 emergency physicians and 161 paramedics, 67.3-78% from each group indicated that their current knowledge of COVID-19 was 'good to very good'. The most frequently accessed source of COVID-19 information was from state department of health websites. Most of the respondents in each group (77.6-86.4%) received COVID-19 specific training and education, including personal protective equipment (PPE) usage. One-third of paramedics reported that their workload 'had lessened' while 36.4-40% of emergency nurses and physicians stated that their workload had 'considerably increased'. Common concerns raised included disease transmission to family, public complacency, and PPE availability.

CONCLUSIONS

Extensive training and education and adequate support helped prepare emergency clinicians to manage COVID-19 patients. Challenges included inconsistent and rapidly changing communications and availability of PPE.

Frontiers in urethra regeneration: current state and future perspective

Despite the positive achievements attained, the treatment of male urethral strictures and hypospadiases still remains a challenge, particularly in cases of severe urethral defects. Complications and the need for additional interventions in such cases are common. Also, shortage of autologous tissue for graft harvesting and significant morbidity in the location of harvesting present problems and often lead to staged treatment. Tissue engineering provides a promising alternative to the current sources of grafts for urethroplasty. Since the first experiments in urethral substitution with tissue engineered grafts, this topic in regenerative medicine has grown remarkably, as many different types of tissue-engineered grafts and approaches in graft design have been suggested and testedin vivo. However, there have been only a few clinical trials of tissue-engineered grafts in urethral substitution, involving hardly more than a hundred patients overall. This indicates that the topic is still in its inception, and the search for the best graft design is continuing. The current review focuses on the state of the art in urethral regeneration with tissue engineering technology. It gives a comprehensive overview of the components of the tissue-engineered graft and an overview of the steps in graft development. Different cell sources, types of scaffolds, assembling approaches, options for vascularization enhancement and preclinical models are considered.

Validated HPLC method for paclitaxel determination in PLGA submicron particles conjugated with α-fetoprotein third domain: Sample preparation case study

OBJECTIVES

The goal of this study was to develop sample preparation method and validate the HPLC method for precise determination of paclitaxel (Ptx) in PLGA submicron particles conjugated with protein vector molecule.

METHODS

Ptx loaded PLGA submicron particles were formulated by a single emulsification method. PLGA submicron particles were conjugated with alpha fetoprotein third domain (rAFP3d) via standard carbodiimide technique. The obtained conjugate was analyzed using 1525 binary pump and 2487 UV-VIS detector system (Waters, USA) and Reprosil ODS C-18 analytical column with the dimensions of 150mm×4.6mm ID×5μm (Dr. Maisch GmbH, Germany). Sample preparation method was developed utilizing guard cartridge with С18 stationary phase (Phenomenex, USA). HPLC method was validated according to the international conference on harmonization guidelines.

RESULTS

Efficient sample preparation was achieved using 4% of DMSO pre-dissolution, following by 10min of centrifugation at 4500g. Ptx determination was performed using acetonitrile/0.1% phosphoric acid (50:50 v/v) mobile phase at a flow rate of 1.0mL/min, injection volume of 10μL, and at 227nm. The developed method showed linearity, accuracy and precision in the range from 0.03 to 360μg/mL, with LOD and LOQ values of 0.005 and 0.03μg/mL, respectively. The intra- and inter-day precisions presented RSD values of lower than 2%.

CONCLUSION

The validated method was successfully applied to calculate Ptx encapsulation efficacy and drug loading in the developed formulation.

X-ray phase-sensitive imaging using a bilens interferometer based on refractive optics

The phase-sensitive X-ray imaging technique based on the bilens interferometer is developed. The essence of the method consists of scanning a sample, which is set upstream of the bilens across the beam of one lens of the interferometer by recording changes in the interference pattern using a high-resolution image detector. The proposed approach allows acquiring the absolute value of a phase shift profile of the sample with a fairly high phase and spatial resolution. The possibilities of the imaging technique were studied theoretically and experimentally using fibres with different sizes as the test samples at the ESRF ID06 beamline with 12 keV X-rays. The corresponding phase shift profile reconstructions and computer simulations were performed. The experimental results are fully consistent with theoretical concepts and appropriate numerical calculations. Applications of the interferometric imaging technique are discussed, as well as future improvements.

A structural-based computational model of tendon-bone insertion tissues

Tendon-to-bone insertion provides a gradual transition from soft tendon to hard bone tissue, functioning to alleviate stress concentrations at the junction of these tissues. Such macroscopic mechanical properties are achieved due to the internal structure in which collagen fibers and mineralization levels are key ingredients. We develop a structural-based model of tendon-to-bone insertion incorporating such details as fiber preferred orientation, fiber directional dispersion, mineralization level, and their inhomogeneous spatial distribution. A python script is developed to alter the tapered tendon-bone transition zone and to provide spatial grading of material properties, which may be rather complex as experiments suggest. A simple linear interpolation between tendon and bone material properties is first used to describe the graded property within the insertion region. Stress distributions are obtained and compared for spatially graded and various piece-wise materials properties. It is observed that spatial grading results in more smooth stress distributions and significantly reduces maximum stresses. The geometry of the tissue model is optimized by minimizing the peak stress to mimic in-vivo tissue remodeling. The in-silico elastic models constructed in this work are verified and modified by comparing to our in-situ biaxial mechanical testing results, thereby serving as translational tools for accurately predicting the material behavior of the tendon-to-bone insertions. This model will be useful for understanding how tendon-to-bone insertion develops during tissue remodeling, as well as for developing orthopedic implants.

A complex morphofunctional approach for zinc toxicity evaluation in rats

Anthropogenic activity causes the introduction of zinc compounds into the biological cycle in mining and processing sites and its accumulation in organs and tissues, causing systemic toxicity. A cumulative effect of zinc is predominantly neurotoxic and it also affects the respiratory, cardiovascular and digestive systems. This study evaluates the effects of single-dose intragastric administration of 100 mg/kg zinc succinate on the structure and function of organs and tissues in male Wistar rats 1 month after treatment. The presented morphofunctional approach for the toxicity evaluation included the study of behavioral responses using the automated Laboras® complex, fluorescent spectral analysis of the NADH and FAD activity and histological evaluation of animal organs and tissues. The results of the behavioral activity assessment showed a significant decrease in animals' motor activity, whereas the fluorescence spectra analysis demonstrated a decrease in coenzyme NADH without the reduction of FAD levels. We detected toxic and dystrophic changes in the cerebral cortex, heart, lungs and liver tissues. Our original multiparametric approach enables a comprehensive assessment of the long-term toxic effects of the metal salts such as zinc succinate, especially in the cerebral cortex at the doses much lower than the acute LD50 reported for the common zinc salts.

Prospective visible laser active media based on disordered fluorite-type structure crystals

The synthesis conditions and the results of spectral-kinetic studies of disordered crystals series CaF2-LaF3-PrF3 with variable chemical composition are presented. The prospects of using these crystals as active media for the visible spectral range DPSS laser pumped by InGaN (GaN) laser diodes and operating on 4f-4f transitions of Pr3+ ions are discussed.

THE VALUE OF QUANTITY OF STREPTOCOCCI ON THE NASAL AND OROPHARYNGEAL MUCOSA ON THE FORMATION OF THE CELLULAR IMMUNITY IN CHILDREN WITH INFECTIOUS MONONUCLEOSIS

The article presents the results of a comparative analysis of the cellular level of the immune response of children with mononucleosis in different periods of the disease of IM in children with different degrees of dissemination by streptococcus from their nasal and oropharyngeal mucosa. To achieve the goal, 60 children aged from three to seven years old with patients with infectious mononucleosis were examined, who were treated at the Regional Children's Infectious Clinical Hospital of Kharkiv, Ukraine. In 30 children (the first group), Streptococcus pyogenes was isolated in concentrations of 10-5 and higher during bacteriological examination of the nasal and oropharyngeal mucosa. 30 (second group) - 10-4 degrees or less. It has been established that the presence of streptococcus concentrations of 10-5 and higher in the naso-pharyngeal mucosa of patients with mononucleosis leads to the development of partial cell immunodeficiency which persists until the period of early convalescence. The presence of streptococcus in a concentration of more than 10-5 on the mucous membrane of the nasopharynx in patients with IM leads not only to changes in the immune response of children, but also affects the severity and duration of clinical manifestations of the disease. In our opinion, pathogenic flora can also contribute to the formation of adverse outcomes of the disease this issue requires further study. The obtained results must be taken into account in treating patients both in the acute period and during the stages of convalescence.

Strain state dependent anisotropic viscoelasticity of tendon-to-bone insertion

Tendon-to-bone insertion tissues may be considered as functionally-graded connective tissues, providing a gradual transition from soft tendon to hard bone tissue, and functioning to alleviate stress concentrations at the junction of these tissues. The tendon-to-bone insertion tissues demonstrate pronounced viscoelastic behavior, like many other biological tissues, and are designed by the nature to alleviate stress at physiological load rates and strains states. In this paper we present experimental data showing that under biaxial tension tendon-to-bone insertion demonstrates rate-dependent behavior and that stress-strain curves for the in-plane components of stress and strain become less steep when strain rate is increased, contrary to a typical viscoelastic behavior, where the opposite trend is observed. Such behavior may indicate the existence of a protective viscoelastic mechanism reducing stress and strain during a sudden increase in mechanical loading, known to exist in some biological tissues. The main purpose of the paper is to show that such viscoelastic stress reduction indeed possible and is thermodynamically consistent. We, therefore, propose an anisotropic viscoelasticity model for finite strain. We identify the range of parameters for this model which yield negative viscoelastic contribution into in-plane stress under biaxial state of strain and simultaneously satisfy requirements of thermodynamics. We also find optimal parameters maximizing the observed protective viscoelastic effect for this particular state of strain. This model will be useful for testing and describing viscoelastic materials and for developing interfaces for dissimilar materials, considering rate effect and multiaxial loadings.

Quantitative assessment of radiation-induced changes of bladder and rectum collagen structure using optical methods

The objective of the study is the quantitative analysis of the dose-time dependences of changes occurring in collagen of bladder and rectum after gamma-irradiation using optical methods [nonlinear microscopy in a second harmonic generation (SHG) detection regime and cross-polarization optical coherence tomography (CP OCT)]. For quantitative assessment of the collagen structure, regions of interest on the SHG-images of two-dimensional (2-D) distribution of SHG signal intensity of collagen were chosen in the submucosa. The mean SHG signal intensity and its standard deviation were calculated by ImageJ 1.39p (NIH). For quantitative analysis of CP OCT data, an integral depolarization factor (IDF) was calculated. Quantitative calculation of the SHG signal intensity and the IDF can provide additional information about the processes of the collagen radiation-induced degradation and subsequent remodeling. High positive correlation between the mean SHG signal intensity and the mean IDF of bladder and rectum demonstrates that CP OCT can be used as an "optical biopsy" in the grading of collagen radiation damage.

Pixel classification method in optical coherence tomography for tumor segmentation and its complementary usage with OCT microangiography

A novel machine-learning method to distinguish between tumor and normal tissue in optical coherence tomography (OCT) has been developed. Pre-clinical murine ear model implanted with mouse colon carcinoma CT-26 was used. Structural-image-based feature sets were defined for each pixel and machine learning classifiers were trained using "ground truth" OCT images manually segmented by comparison with histology. The accuracy of the OCT tumor segmentation method was then quantified by comparing with fluorescence imaging of tumors expressing genetically encoded fluorescent protein KillerRed that clearly delineates tumor borders. Because the resultant 3D tumor/normal structural maps are inherently co-registered with OCT derived maps of tissue microvasculature, the latter can be color coded as belonging to either tumor or normal tissue. Applications to radiomics-based multimodal OCT analysis are envisioned.

Primary hyperparathyroidism in young patients in Russia: high frequency of hyperparathyroidism-jaw tumor syndrome

BACKGROUND

Primary hyperparathyroidism (PHPT) is a relatively rare disorder among children, adolescents and young adults. Its development at an early age is suspicious for hereditary causes, though the need for routine genetic testing remains controversial.

OBJECTIVE

To identify and describe hereditary forms of PHPT in patients with manifestation of the disease under 40 years of age.

DESIGN

We enrolled 65 patients with PHPT diagnosed before 40 years of age. Ten of them had MEN1 mutation, and PHPT in them was the first manifestation of multiple endocrine neoplasia type 1 syndrome.

METHODS

The other fifty-five patients underwent next-generation sequencing (NGS) of a custom-designed panel of genes, associated with PHPT (MEN1, CASR, CDC73, CDKN1A, CDKN1B, CDKN1C, CDKN2A, CDKN2C, CDKN2D). In cases suspicious for gross CDC73 deletions multiplex ligation-dependent probe amplification was performed.

RESULTS

NGS revealed six pathogenic or likely pathogenic germline sequence variants: four in CDC73 c.271C>T (p.Arg91*), c.496C>T (p.Gln166*), c.685A>T (p.Arg229*) and c.787C>T (p.Arg263Cys); one in CASR c.3145G>T (p.Glu1049*) and one in MEN1 c.784-9G>A. In two patients, MLPA confirmed gross CDC73 deletions. In total, 44 sporadic and 21 hereditary PHPT cases were identified. Parathyroid carcinomas and atypical parathyroid adenomas were present in 8/65 of young patients, in whom CDC73 mutations were found in 5/8.

CONCLUSIONS

Hereditary forms of PHPT can be identified in up to 1/3 of young patients with manifestation of the disease at <40 years of age. Parathyroid carcinomas or atypical parathyroid adenomas in young patients are frequently associated with CDC73 mutations.

Seed-effect modeling improves the consistency of genome-wide loss-of-function screens and identifies synthetic lethal vulnerabilities in cancer cells

Background

Genome-wide loss-of-function profiling is widely used for systematic identification of genetic dependencies in cancer cells; however, the poor reproducibility of RNA interference (RNAi) screens has been a major concern due to frequent off-target effects. Currently, a detailed understanding of the key factors contributing to the sub-optimal consistency is still a lacking, especially on how to improve the reliability of future RNAi screens by controlling for factors that determine their off-target propensity.

Methods

We performed a systematic, quantitative analysis of the consistency between two genome-wide shRNA screens conducted on a compendium of cancer cell lines, and also compared several gene summarization methods for inferring gene essentiality from shRNA level data. We then devised novel concepts of seed essentiality and shRNA family, based on seed region sequences of shRNAs, to study in-depth the contribution of seed-mediated off-target effects to the consistency of the two screens. We further investigated two seed-sequence properties, seed pairing stability, and target abundance in terms of their capability to minimize the off-target effects in post-screening data analysis. Finally, we applied this novel methodology to identify genetic interactions and synthetic lethal partners of cancer drivers, and confirmed differential essentiality phenotypes by detailed CRISPR/Cas9 experiments.

Results

Using the novel concepts of seed essentiality and shRNA family, we demonstrate how genome-wide loss-of-function profiling of a common set of cancer cell lines can be actually made fairly reproducible when considering seed-mediated off-target effects. Importantly, by excluding shRNAs having higher propensity for off-target effects, based on their seed-sequence properties, one can remove noise from the genome-wide shRNA datasets. As a translational application case, we demonstrate enhanced reproducibility of genetic interaction partners of common cancer drivers, as well as identify novel synthetic lethal partners of a major oncogenic driver, PIK3CA, supported by a complementary CRISPR/Cas9 experiment.

Conclusions

We provide practical guidelines for improved design and analysis of genome-wide loss-of-function profiling and demonstrate how this novel strategy can be applied towards improved mapping of genetic dependencies of cancer cells to aid development of targeted anticancer treatments.

Electronic supplementary material

The online version of this article (doi:10.1186/s13073-017-0440-2) contains supplementary material, which is available to authorized users.

Linear parabolic single-crystal diamond refractive lenses for synchrotron X-ray sources

Linear parabolic diamond refractive lenses are presented, designed to withstand high thermal and radiation loads coming from upgraded accelerator X-ray sources. Lenses were manufactured by picosecond laser treatment of a high-quality single-crystal synthetic diamond. Twelve lenses with radius of curvature at parabola apex R = 200 µm, geometrical aperture A = 900 µm and length L = 1.5 mm were stacked as a compound refractive lens and tested at the ESRF ID06 beamline. A focal spot of size 2.2 µm and a gain of 20 were measured at 8 keV. The lens profile and surface quality were estimated by grating interferometry and X-ray radiography. In addition, the influence of X-ray glitches on the focusing properties of the compound refractive lens were studied.

30-Lens interferometer for high-energy X-rays

A novel high-energy multi-lens interferometer consisting of 30 arrays of planar compound refractive lenses is reported. Under coherent illumination each lens array creates a diffraction-limited secondary source. Overlapping such coherent beams produces an interference pattern demonstrating strong longitudinal functional dependence. The proposed multi-lens interferometer was tested experimentally at the 100 m-long ID11 ESRF beamline in the X-ray energy range from 30 to 65 keV. The interference pattern generated by the interferometer was recorded at fundamental and fractional Talbot distances. An effective source size (FWHM) of the order of 15 µm was determined from the first Talbot image, proving the concept that the multi-lens interferometer can be used as a high-resolution tool for beam diagnostics.

BRCA1-deficient breast cancer cell lines are resistant to MEK inhibitors and show distinct sensitivities to 6-thioguanine

Germ-line or somatic inactivation of BRCA1 is a defining feature for a portion of human breast cancers. Here we evaluated the anti-proliferative activity of 198 FDA-approved and experimental drugs against four BRCA1-mutant (HCC1937, MDA-MB-436, SUM1315MO2, and SUM149PT) and four BRCA1-wild-type (MDA-MB-231, SUM229PE, MCF10A, and MCF7) breast cancer cell lines. We found that all BRCA1-mutant cell lines were insensitive to inhibitors of mitogen-activated protein kinase kinase 1 and 2 (MEK1/2) Selumetinib and Pimasertib in contrast to BRCA1-wildtype control cell lines. However, unexpectedly, only two BRCA1-mutant cell lines, HCC1937 and MDA-MB-436, were hypersensitive to a nucleotide analogue 6-thioguanine (6-TG). SUM149PT cells readily formed radiation-induced RAD51-positive nuclear foci indicating a functional homologous recombination, which may explain their resistance to 6-TG. However, the reason underlying 6-TG resistance of SUM1315MO2 cells remains unclear. Our data reveal a remarkable heterogeneity among BRCA1-mutant cell lines and provide a reference for future studies.

Prolonged dry apnoea: effects on brain activity and physiological functions in breath-hold divers and non-divers

PURPOSE

The aim of the study was to investigate the effects of voluntary breath-holding on brain activity and physiological functions. We hypothesised that prolonged apnoea would trigger cerebral hypoxia, resulting in a decrease of brain performance; and the apnoea's effects would be more pronounced in breath-hold divers.

METHODS

Trained breath-hold divers and non-divers performed maximal dry breath-holdings. Lung volume, alveolar partial pressures of O2 and CO2, attention and anxiety levels were estimated. Heart rate, blood pressure, arterial blood oxygenation, brain tissue oxygenation, EEG, and DC potential were monitored continuously during breath-holding.

RESULTS

There were a few significant changes in electrical brain activity caused by prolonged apnoea. Brain tissue oxygenation index and DC potential were relatively stable up to the end of the apnoea in breath-hold divers and non-divers. We also did not observe any decrease of attention level or speed of processing immediately after breath-holding. Interestingly, trained breath-hold divers had some peculiarities in EEG activity at resting state (before any breath-holding): non-spindled, sharpened alpha rhythm; slowed-down alpha with the frequency nearer to the theta band; and untypical spatial pattern of alpha activity.

CONCLUSION

Our findings contradicted the primary hypothesis. Apnoea up to 5 min does not lead to notable cerebral hypoxia or a decrease of brain performance in either breath-hold divers or non-divers. It seems to be the result of the compensatory mechanisms similar to the diving response aimed at centralising blood circulation and reducing peripheral O2 uptake. Adaptive changes during apnoea are much more prominent in trained breath-hold divers.

Hard x-ray single crystal bi-mirror

We report a novel hard x-ray interferometer consisting of two parallel channels manufactured in a single Si crystal by means of microfabrication technology. The sidewall surfaces of the channels, similar to mirrors, scatter at very small incident angles, acting equivalently to narrow micrometer size slits as in the Young double-slit interferometer. Experimental tests of the interferometer were performed at the ESRF ID06 beamline in the energy range from 12 to 16 keV. The interference patterns at different grazing incidence angles were recorded in the near- and far-field. Evaluation of the influence of the channel surface roughness on the visibility of interference fringes was performed. The proposed interferometer design allows the arrangement of mirrors at different split distances.

Large-acceptance diamond planar refractive lenses manufactured by laser cutting

For the first time, single-crystal diamond planar refractive lenses have been fabricated by laser micromachining in 300 µm-thick diamond plates which were grown by chemical vapour deposition. Linear lenses with apertures up to 1 mm and parabola apex radii up to 500 µm were manufactured and tested at the ESRF ID06 beamline. The large acceptance of these lenses allows them to be used as beam-conditioning elements. Owing to the unsurpassed thermal properties of single-crystal diamond, these lenses should be suitable to withstand the extreme flux densities expected at the planned fourth-generation X-ray sources.

X-ray multilens interferometer based on Si refractive lenses

We report a multilens X-ray interferometer consisting of six parallel arrays of planar compound refractive lenses, each of which creates a diffraction limited beam under coherent illumination. Overlapping such coherent beams produces an interference pattern demonstrating substantially strong longitudinal functional dependence. The interference fringe pattern produced by multilens interferometer was described by Talbot imaging formalism. Theoretical analysis of the interference pattern formation was carried out and corresponding computer simulations were performed. The proposed multilens interferometer was experimentally tested at ID06 ESRF beamline in the X-ray energy range from 10 to 30 keV. The experimentally recorded fractional Talbot images are in a good agreement with computer simulations.

Fourier crystal diffractometry based on refractive optics

X-ray refractive lenses are proposed as a Fourier transformer for high-resolution X-ray crystal diffraction. By employing refractive lenses the wave transmitted through the object converts into a spatial intensity distribution at its back focal plane according to the Fourier-transform relations. A theoretical consideration of the Fourier-transform technique is presented. Two types of samples were studied in Bragg reflection geometry: a grating made of strips of a thin SiO2film on an Si substrate and a grating made by profiling an Si crystal. Fourier patterns recorded at different angles along the rocking curves of the Si 111 Bragg reflection were analysed.

Measuring tumor aggressiveness and targeting metastatic lesions with fluorescent pHLIP

PURPOSE

Malignant cancer foci develop acidic extracellular environments. Mild acidic conditions trigger insertion and folding of the pH (low) insertion peptide (pHLIP(TM)) across a cellular membrane, enabling targeting of such lesions.

PROCEDURES

We employed optical imaging to follow targeting by fluorescent pHLIP given i.v. in mice. For visualization, Cy5.5 and Alexa750 were covalently attached to the N terminus of pHLIP, which stays outside of a cell membrane after transmembrane insertion.

RESULTS

We demonstrate that pHLIP targets: (a) tumors of different origins established by subcutaneous injection of cancer cells, (b) spontaneous prostate tumors in TRAMP mice and (c) metastatic lesions in lung pHLIP accumulation in tumors correlates with tumor aggressiveness. Within a tumor, it stains extracellular spaces and cellular membranes.

CONCLUSIONS

Tissue acidity can be detected by pHLIP peptide insertion and used to diagnose primary tumors, metastatic lesions, and lipid bodies in necrotic tissues. The ability of pHLIP to differentially bind metastatic and non-metastatic tumors may provide a new approach for evaluating cancer prognosis.

Analysis of undiagnosed tuberculosis-related deaths identified at post-mortem among HIV-infected patients in Russia: a descriptive study

Background

Tuberculosis remains a serious public health threat and economic burden in Russia with escalating rates of drug resistance against a background of growing HIV-epidemic. Samara Oblast is one of the regions of the Russian Federation where more than 1% of the population is affected by the HIV-epidemic; almost half of the cases are concentrated in the largely-industrial city of Togliatti with a population of 800 000.

Methods

We conducted a retrospective analysis of errors leading to death of HIV-positive patients in general health care hospitals in Togliatti, Russia, in 2008. All (n = 29) cases when tuberculosis was established at autopsy as a cause of death were included.

Results

Median length of hospital stay was 20 days; in 11 cases the death occurred within the first 24 hours of admission. All cases were known to be HIV-positive prior to admission, however HAART was not initiated for any case, and no relevant tests to assess severity of immunosupression were performed despite their availability. No appropriate diagnostic algorithms were applied to confirm tuberculosis. Major gaps were identified in the work of hospital and consulting physicians including insufficient records keeping. In almost all patients earlier regular HIV-relevant tests were not performed due to poor compliance of patients, many of whom abused alcohol and drugs.

Conclusions

We conclude that introduction of prompt and accurate diagnostics tests, adequate treatment protocols and intensive training of physicians in management of AIDS and TB is vital. This should include reviewing standards of care for HIV-positive individuals with accompanying social problems.

Abstract 228: A comprehensive study to functionally classify the BRCA2 missense mutations found in Fanconi anemia patients

Biallelic mutations in breast cancer susceptibility gene 2 (BRCA2) cause a severe Fanconi Anemia (FA) phenotype that is a rare recessive disorder and reflects the cellular and phenotypic consequences of genetic instability. A number of mutations found in FA patients are missense mutations in BRCA2 and classified as variants of unknown clinical significance. This study is aimed towards the evaluation of functional significance of a few BRCA2 unclassified variants.

In this study, six of the human mutations (L2510P, R2336H, I2490T, W2626C, K2729N and IVS7+2T&gt;G) were generated in human BRCA2 gene cloned in a bacterial artificial chromosome vector. The effect of these variants on BRCA2 function was examined by using a mouse embryonic stem (ES) cell-based assay. We have shown the ability of wild-type human BRCA2 and neutral BRCA2 variants to rescue the lethality of Brca2-null mouse ES cells and functionally complement the loss of endogenous mouse Brca2. W2626C and IVS 7+2T&gt;G mutations failed to restore the viability of ES cell colonies after deletion of the endogenous mouse Brca2. The K2729N BRCA2 rescued the ES cell lethality and appeared similar to wild-type BRCA2 in various functional assays. In contrast, L2510P and R2336H BRCA2 exhibited reduced ES cell viability. In addition, ES cells expressing L2510P BRCA2 are sensitive to DNA damaging agents. Furthermore, L2510P BRCA2 mutant ES cells are slow growing, have increased genomic instability, defective in G1-S checkpoint control and show upregulation of p53 and p21. These mutant cells are defective in homologous recombination mediated DNA repair. IVS7+2T&gt;G and R2336H mutations result in exon-skipping leading to premature protein truncation. Alterations in L2510P, I2490T, W2626C and K2729N map to a highly conserved region of BRCA2 and the homology based molecular modeling of the mutant proteins supports our ES-cell results. L2510P and W2626C mutations disrupt the BRCA2 structure and the interaction of BRCA2 with a highly conserved protein DSS1, whereas I2490T and K2729N mutations do not affect the BRCA2 structure and are neutral in nature. It is possible that the patients with the variant alleles that are neutral in this assay have other undetected mutation in that allele or have mutations in some other FA genes. In conclusion, this study provides functional classification of a few variants of unknown clinical significance that should help in counseling individuals carrying these alleles.

.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 228. doi:10.1158/1538-7445.AM2011-228

X-ray nanointerferometer based on si refractive bilenses

We report a novel type of x-ray interferometer employing a bilens system consisting of two parallel compound refractive lenses, each of which creates a diffraction limited beam under coherent illumination. By closely overlapping such coherent beams, an interference field with a fringe spacing ranging from tens of nanometers to tens of micrometers is produced. In an experiment performed with 12 keV x rays, submicron fringes were observed by scanning and moiré imaging of the test grid. The far field interference pattern was used to characterize the x-ray coherence. Our technique opens up new opportunities for studying natural and man-made nanoscale materials.

The growth and tumor suppressors NORE1A and RASSF1A are targets for calpain-mediated proteolysis

Background

NORE1A and RASSF1A are growth and tumour suppressors inactivated in a variety of cancers. Methylation of NORE1A and RASSF1A promoters is the predominant mechanism for downregulation of these proteins; however, other mechanisms are likely to exist.

Methodology/Principal Findings

Here we describe a proteolysis of NORE1A and RASSF1A by calpains as alternative mechanism of their downregulation. Extracts of H358 cell line, a human bronchoalveolar carcinoma, and H460, a large cell carcinoma, were capable of proteolysis of NORE1A protein in the calpain-dependent manner. Likewise, RASSF1A tumor suppressor was proteolyzed by the H358 cell extract. Addition of calpain inhibitor to H358 and H460 cells growing in tissue culture resulted in re-expression of endogenous NORE1A. A survey of 10 human lung tumours revealed that three of them contain an activity capable of inducing NORE1A degradation.

Conclusions/Significance

Thus, degradation by calpains is a novel mechanism for downregulation of NORE1A and RASSF1A proteins and might be the mechanism allowing cancer cells to escape growth suppression.

Interaction of the growth and tumour suppressor NORE1A with microtubules is not required for its growth-suppressive function

BACKGROUND

The NORE1 protein was identified in a yeast two-hybrid screen as a Ras effector that binds Ras protein in a GTP-dependent manner. NORE1A is a growth and tumour suppressor that is inactivated in a variety of cancers. In transformed human cells, both full-length NORE1A protein and its effector domain alone (amino acids 191-363) are localized to microtubules and centrosomes. However, the mechanism by which NORE1A associates with these cytoskeletal elements is not known; furthermore, whether centrosomally-associated or microtubule-associated NORE1A suppresses tumour cell growth has not been yet established.

FINDINGS

We have shown that purified NORE1A fails to bind to microtubules in vitro suggesting that other protein(s) mediate NORE1A-microtubule association. Using mass-spectrometry, we identified the Microtubule-Associated Protein 1B (MAP1B) and its homologue C19ORF5 as NORE1A interaction partners. Suppression of C19ORF5 expression by RNA interference (RNAi) and immunodepletion of C19ORF5 protein from cell extracts showed that binding of NORE1A to microtubules is not dependent on C19ORF5. Conversely, RNAi suppression of MAP1B revealed that MAP1B is required for association of NORE1A with microtubules. RNAi-mediated depletion of C19ORF5 or MAP1B did not prevent centrosomal localization of NORE1A. Moreover, the depletion of C19ORF5 or MAP1B did not prevent NORE1A's ability to suppress tumour cell growth.

CONCLUSION

The interaction of NORE1A with microtubules is mediated by MAP1B, but not C19ORF5 protein. Interaction of NORE1A with centrosomes is not dependent on C19ORF5 or MAP1B, and appears to involve a different mechanism independent of binding to microtubules. The NORE1A microtubular localization is not required for growth suppression.

RAD51C deficiency in mice results in early prophase I arrest in males and sister chromatid separation at metaphase II in females

RAD51C is a member of the RecA/RAD51 protein family, which is known to play an important role in DNA repair by homologous recombination. In mice, it is essential for viability. Therefore, we have generated a hypomorphic allele of Rad51c in addition to a null allele. A subset of mice expressing the hypomorphic allele is infertile. This infertility is caused by sexually dimorphic defects in meiotic recombination, revealing its two distinct functions. Spermatocytes undergo a developmental arrest during the early stages of meiotic prophase I, providing evidence for the role of RAD51C in early stages of RAD51-mediated recombination. In contrast, oocytes can progress normally to metaphase I after superovulation but display precocious separation of sister chromatids, aneuploidy, and broken chromosomes at metaphase II. These defects suggest a possible late role of RAD51C in meiotic recombination. Based on the marked reduction in Holliday junction (HJ) resolution activity in Rad51c-null mouse embryonic fibroblasts, we propose that this late function may be associated with HJ resolution.

Health system frailties in tuberculosis service provision in Russia: an analysis through the lens of formal nutritional support

OBJECTIVE

The aim of this study was to describe health system challenges faced by tuberculosis (TB) treatment facilities in Russia through an analysis of formal institutional dietary provisions to patients in an inpatient facility that provides care for poor patients.

METHODS

Analysis of formal dietary provisions by institutions and financing data from TB hospitals in Samara Oblast, Russia.

RESULTS

Formal dietary provision for inpatients with TB has fallen substantially in recent years. In a hospital providing inpatient care for the poorest patients with fewest social support networks, this has been very pronounced. The likely reason for this is that financial support for other budget lines, principally salaries, has required protection.

CONCLUSION

Formal institutional nutritional support in institutions providing care for the poorest patients with TB is unlikely to be enhancing the speed of recovery, or reducing the duration of infectiousness. Furthermore, the role that hospital may have played in the past in enabling patients to regain weight lost before admission may have been limited by reductions in formal financing. Reductions in state provision of food for patients may serve as an important illustration of wider TB control system frailties in the Russian Federation.

Antimicrobial prescribing patterns for respiratory diseases including tuberculosis in Russia: a possible role in drug resistance?

BACKGROUND

Inappropriate antibiotic prescribing exposes patients to the risk of side effects and encourages the development of drug resistance across antimicrobial groups used for respiratory infections including tuberculosis (TB).

AIM

Determine among Russian general practitioners and specialists: (1) sources of antimicrobial prescribing information; (2) patterns of antimicrobial prescribing for common respiratory diseases and differences between primary and specialist physicians; (3) whether drug resistance in TB might be linked to over-prescribing of anti-TB drugs for respiratory conditions.

METHODS

Point-prevalence cross-sectional survey involving all 28 primary care, general medicine and TB treatment institutions in Samara City, Russian Federation. In this two-stage study, a questionnaire was used to examine doctors' antimicrobial (including TB drugs) prescribing habits, sources of prescribing information, management of respiratory infections and a case scenario ('common cold'). This was followed by a case note review of actual prescribing for consecutive patients with respiratory diseases at three institutions.

RESULTS

Initial questionnaires were completed by 81.3% (425/523) of physicians with 78.4% working in primary care. Most doctors used standard textbooks to guide their antimicrobial practice but 80% made extensive use of pharmaceutical company information. A minority of 1.7% would have inappropriately prescribed antibiotics for the case and 0.8-1.8% of respondents would have definitely prescribed TB drugs for non-TB conditions. Of the 495 respiratory cases, 25% of doctors prescribed an antibiotic for a simple upper respiratory tract infection and of 8 patients with a clinical diagnosis of TB, 4 received rifampicin monotherapy alone. Ciprofloxacin was widely but inappropriately used.

CONCLUSION

Doctors rely on information provided by pharmaceutical companies; there was inappropriate antibiotic prescribing.