Bone Organ Research Articles

Technique for determining the orthotropic properties of the bone organ according to computer tomography

The actual task of modern biomechanics of bone tissue is to determine the elastic properties. Nowadays computed tomography coupled with computer technology allows the use of numerical experiments to determine the mechanical properties of biological objects. This paper presents such a technique. The technique is based on the hypothesis that the anisotropy of bone tissue is determined by the uneven distribution of pore volume. In the proposed approach, the organ under study is proposed to be divided into a set of representative volumes. A set of numerical experiments is carried out for each volume, which makes it possible to determine the components of the elastic tensor. Then, the axes of orthotropy and elastic constants are determined. The described technique is applied for diaphysis of the femoral bone rat. It is shown that the resulting elastic constants remain constant in the organ, and the body is transversally isotropic.

Establishing a prostate cancer referral pathway between urology and medical oncology at Lyndon B. Johnson Hospital.

60 Background: Treatment for biochemically recurrent (bcr) and metastatic prostate cancer (pc) is evolving, making multidisciplinary evaluation a critical need. Our center, a community public hospital, lacked clear referral criteria between the Urology (Uro) and Medical Oncology (Onc) clinics, resulting in inconsistent care. We aimed to improve multidisciplinary communication and the rate of patient (pt) referrals by establishing standardized referral criteria for pc pts between Uro and Onc. Methods: Referral criteria were based on the presence or concern for primary refractory, bcr, castrate resistant (cr), or metastatic pc, as established by the PCWG3 and RTOG-ASTRO Phoenix consensuses. Primary refractory pc was defined as a failure of the PSA to fall to undetectable levels after radical prostatectomy (rp). Bcr pc was defined as two consecutive PSA values ≥ 0.2ng/mL after rp, or a rise in PSA 2ng/mL above post-treatment nadir after radiation therapy. Cr pc was defined as radiographic (progressive measurable disease) or chemical (two rising PSA levels 6-12 weeks apart) progression despite castrate levels of testosterone (T), defined as a serum T < 50ng/dL. Metastatic pc was defined as the development of bone lesion(s), organ involvement, or lymphadenopathy above the bifurcation of common iliac vessels. The referral criteria were organized into a chart and visibly displayed, discussed during multidisciplinary meetings, and distributed during educational sessions with Uro Residents and Onc Fellows in January 2019. Referral rate was collected from July 2018 through December 2018, and collection of post-intervention referral rate is planned from January 2019 through June 2019. Results: Pre-intervention, 39% (23/59 pts) of the pts that met referral criteria were referred to Onc. Preliminary data from January through April 2019 demonstrated a referral rate of 60% (9/15 pts). Conclusions: In 4 months, our intervention improved the referral rate by 21%. These criteria continue to be reinforced during multidisciplinary meetings and more educational sessions are planned as new personnel establish in the clinics. Ultimately, more time and pts are required to determine the full impact of this project.

Inflammation and Bone Repair: From Particle Disease to Tissue Regeneration.

When presented with an adverse stimulus, organisms evoke an immediate, pre-programmed, non-specific innate immune response. The purpose of this reaction is to maintain the organism's biological integrity and function, mitigate or eradicate the injurious source, and re-establish tissue homeostasis. The initial stage of this protective reaction is acute inflammation, which normally reduces or terminates the offending stimulus. As the inflammatory reaction recedes, the stage of tissue repair and regeneration follows. If the above sequence of events is perturbed, reconstitution of normal biological form and function will not be achieved. Dysregulation of these activities may result in incomplete healing, fibrosis, or chronic inflammation. Our laboratory has studied the reaction to wear particles from joint replacements as a paradigm for understanding the biological pathways of acute and chronic inflammation, and potential translational treatments to reconstitute lost bone. As inflammation is the cornerstone for healing in all anatomical locations, the concepts developed have relevance to tissue engineering and regenerative medicine in all organ systems. To accomplish our goal, we developed novel in vitro and in vivo models (including the murine femoral continuous intramedullary particle infusion model), translational strategies including modulation of macrophage chemotaxis and polarization, and methods to interfere with key transcription factors NFκB and MyD88. We purposefully modified MSCs to facilitate bone healing in inflammatory scenarios: by preconditioning the MSCs, and by genetically modifying MSCs to first sense NFκB activation and then overexpress the anti-inflammatory pro-regenerative cytokine IL-4. These advancements provide significant translational opportunities to enhance healing in bone and other organs.

The antiresoptive effects of recombinant Lingzhi-8 protein against retinoic acid-induced osteopenia

The antiresorptive agents still are the mainstay of osteoporosis treatment. This study aimed to investigate the efficacy of recombinant Lingzhi-8 (rLZ-8) on osteoclast in vitro and bone resorption in vivo. The rLZ-8 protein was derived from Ganoderma lucidum transformation and produced by a genetic system. Receptor activator of nuclear factor kappa-Β ligand induced RAW 264.7 cells to differentiate into osteoclastic cells in vitro. Cells were exposed to different doses of rLZ-8 for 7 days to measure differences of osteoclastic differentiation, apoptosis rate and gene expression. rLZ-8 was labeled with Alexa Fluor 568 to observe its intracellular distribution under super-resolution light microscopy. In addition, retinoic acid was administered to female rats for 14 days to develop osteopenia changes. Different doses of rLZ-8 were simultaneously administered to rats treated with retinoic acid to observe changes of bone mineral density, biochemical parameters and organ weight ratio. Results indicated that rLZ-8 regulated receptor activator of nuclear factor kappa-Β (RANK) - tumor necrosis factor receptor-associated factor 6 (TRAF6) - c-Jun N-terminal kinase (JNK) signaling pathway, by which rLZ-8 inhibited osteoclastic differentiation and promoted osteoclastic apoptosis. Through 3D-structured illumination microscopy, it was observed that rLZ-8 entered RAW264.7 cells and accumulated gradually into the cytoplasm but little into nucleus. Administration with rLZ-8 reversed loss of bone mass and improved ALP activity in osteoporotic rats. Low-to high-dose rLZ-8 treatments displayed little toxic effects on rat organs and did not seem to impact their overall health. All data suggested that rLZ-8 has possible action against osteoporosis.

Identification of Bovine Growth Hormone (BGH) Gene Polymorphism Using PCR-RFLP Method in Buffalo Bulls

Growth Hormone (GH) is a single polypeptide chain synthesised and secreted from anterior pituitary gland by somatroph cells. The product of GH gene hastens metabolism and promotes the growth of many organs and tissues especially bone, muscle and visceral organs. It also regulates growth, mammary gland development and lactation. Polymorphism in this gene is associated with increase in growth and development of many tissues in the body.
 Aim: The objective of this study was to investigate the polymorphism of bovine growth hormone (bGH) gene in buffalo bulls (Bubalus bubalis) using the PCR-RFLP (polymerase chain reaction–restriction fragment length polymorphism) technique.
 Design: Genomic DNA was extracted from a total of 10 bulls, consisting of Murrah – Swamp crossbred and pure Swamp buffalo bulls. A The 446 segment of the bGH gene was amplified. The DNA amplicons were detected in 2% agarose gel following 45 minutes of electrophoresis. They were thereafter digesting with AluI endonuclease restriction enzyme, and the digested DNA were detected in 2% agarose gel following electrophoresis for about 45minutes in all samples
 Results: Similar bands of approximately 300 and 146-bp each, with no variation, were detected in 2% agarose gel following electrophoresis in all the animals tested.
 Conclusion: Based on the Alu1 digestion result, all samples produced the same allele of the gene, with no polymorphism detected.

Fate Distribution and Regulatory Role of Human Mesenchymal Stromal Cells in Engineered Hematopoietic Bone Organs.

SummaryThe generation of humanized ectopic ossicles (hOss) in mice has been proposed as an advanced translational and fundamental model to study the human hematopoietic system. The approach relies on the presence of human bone marrow-derived mesenchymal stromal cells (hMSCs) supporting the engraftment of transplanted human hematopoietic stem and progenitor cells (HSPCs). However, the functional distribution of hMSCs within the humanized microenvironment remains to be investigated. Here, we combined genetic tools and quantitative confocal microscopy to engineer and subsequently analyze hMSCs′ fate and distribution in hOss. Implanted hMSCs reconstituted a humanized environment including osteocytes, osteoblasts, adipocytes, and stromal cells associated with vessels. By imaging full hOss, we identified rare physical interactions between hMSCs and human CD45+/CD34+/CD90+ cells, supporting a functional contact-triggered regulatory role of hMSCs. Our study highlights the importance of compiling quantitative information from humanized organs, to decode the interactions between the hematopoietic and the stromal compartments.

Clinicopathological Analysis of Children's Systemic EBV-Positive T-Cell Lymphoma

To explore the clinical and pathologic features as well as prognosis of systemic EBV-positive T-cell lymphoma in children. The clinical data including clinical manifestation, pathologic changes and treatment in 16 patients with children's systemic EBV-positive T-cell lymphoma were analyzed retrospectively, and follow-up of patients were carried out. The 16 cases included 12 males and 4 females with median age of 3.3 years old. It was demonstrated that the clinical and pathological features of the children's systemic EBV-positive T-cell lymphoma were as followed fever, hepatosplenomegaly, cytopenia, lymphadenopathy, and hemophagocytosis in bone marrow or organ. Histologically, the structures of lymph node was normal, partially or completely destoryed. The paracortical zone was expanded with prominent infiltration of small to medium-sized atypical lymphocytes. The major immunophenotypic characteristics were as follows: (1) Almost all biopsies exhibited prominent T cell proliferation. (2) CD3 was expressed in 16 patients (100%, 16/16), CD4 in 5 patients (31.3%, 5/16)，CD5 in 13 patients (81.3%, 13/16)，CD7 was expressed in 11 patients (68.8%, 11/16)，CD8 in 15 patients (93.8%, 15/16)，CD4 and CD8 were expressed in 5 patients (31.3%, 5/16)，CD4 and CD8 double-negative in patients (6.3%, 1/16)，16 patients were CD56 negative (100%, 16/16). (3) TCR gene cloning rearrangement in 16 patients (93.8%, 15/16). (4) EBV-EBER was expressed in 16 patients (100%, 16/16). 11 out of 16 cases died, 1 cese failed to be followed up, 1 case relapsed，and 3 cases survived, reseptively. The media survival time was 4 months. Systemic EBV-positive T-cell lymphoma predominantly occurred in childhood and early teen-age, and lacks specific clinic features, usually combined with hemophagocytic syndrome. The confirmed diagnosis requires comprehensive analysis of clinical manifestation, pathomorphology, immunohistochemical detection, EBV-EBER insite hybridization, and TCR gene test. The overall prognosis of the disease is poor and the fatality rate is high.

Bone parameters and organ morphometry of two broiler chicken lines exposed to heat for different periods

The objective of this study was to evaluate the effects of different times of exposure to heat on bone parameters and organ morphometry of Cobb Slow® and Hubbard Flex® broilers exposed to high temperatures for 1, 2 or 3 h daily, from 14 days of age. A total of 1120 one-day-old male chicks (half of each line; average weight of 44 g) were housed into 32 cages with 35 birds each, in a randomized-block experimental design. From the first to the 13th day of age, the birds remained under the thermal conditions recommended for their lines; thereafter, from the 14th day, the shed was separated into four parallel sections of 5.60 × 10.20 × 2.8 m delimited by double-sided plastic curtains along the width of the shed. Cyclic heat stress was generated by average temperatures of 36 ºC from 14-20 days, 35 °C from 21-27 days, 34 °C from 28-34 days and 33 °C from 35-42 days. The total length, width, density and mineral matter of the tibia; the size of the duodenum, jejunum and ileum; and the weights of the bursa of Fabricius and spleen were measured. No interaction effect between thermal environment and line was observed. Heat stress for up to 3 h daily, from the 14th to the 41st day of age, led to a longer but narrower tibia. There was no influence on small intestine morphometry. The Hubbard line presented longer and wider tibiae as well as higher relative and absolute weights of the bursa. In conclusion, heat stress from 2 h daily modifies the structure of the tibia in broilers, which increases in length and reduces in width, but heat exposure has no influence on the small intestine or lymphoid organs. The Hubbard line shows better tibia development than the Cobb line as well as different primary lymphoid responses, represented by a heavier bursa.

Abstract SY23-01: Blood-borne tumor cell dissemination in cancer patients

Abstract SY23-01: Blood-borne tumor cell dissemination in cancer patients

Abstract 103: Disruption of Notch Signaling targeted to the myeloma bone marrow microenvironment simultaneously inhibits tumor growth and prevents bone loss without inducing gut toxicity

Abstract Communication between myeloma (MM) cells and cells of the bone marrow via Notch signaling promotes tumor growth/survival and stimulates bone resorption. Systemic inhibition of Notch, using γ-secretase inhibitors (GSIs), decreases MM growth and reduces bone destruction, but the clinical use of GSIs is limited due to dose-limiting severe gut toxicity. To circumvent GSI side effects, we generated a bone specific Notch inhibitor (BT-GSI) by conjugating GSI-XII to a targeting molecule (BT) with high bone affinity using an acid hydrolyzable linker. In vitro, BT-GSI was inactive unless pre-incubated at low pH, and exhibited equal inhibition of Notch target genes in MM cells as unconjugated GSI. Ex vivo, BT-GSI decreased Notch expression and reduced MM growth in bone organ cultures that reproduce acidic conditions in the MM-bone microenvironment. In vivo, treatment with BT-GSI (5mg/kg/3x/wk, i.p.) for 2 wks decreased Notch signaling in bone more efficiently than unconjugated GSI (10mg/kg/5x/wk, i.p.) in naïve mice. In addition, BT-GSI increased cancellous bone mass (30%) and decreased bone resorption by 40%, without affecting bone formation. In contrast, these parameters remained unchanged by GSI. Next, we examined in vivo the impact of BT-GSI on MM growth and bone disease in a preclinical model of established MM. 8-wk-old immunodeficient mice were injected intratibially with 105 JJN3 human MM (hMM) cells or saline. hMM injected mice exhibited detectable serum levels of the tumor biomarker human K-light chain (40 ng/mL) and visible osteolytic disease (osteolytic area 1.7 mm2) 3 wks after hMM inoculation. Then, hMM-injected mice were randomized based on tumor levels to two subgroups to receive either BT-GSI (10mg/kg/3x/wk) or vehicle (DMSO) for 3 wks. Saline-injected mice received vehicle injections. BT-GSI selectively decreased Notch gene expression in bone, but had no effect in the brain or gut. Further, BT-GSI did not increase the expression of Adipsin in the gut, a biomarker of gut toxicity, nor showed evidence of gut toxicity at necropsy. Mice treated with BT-GSI exhibited a 45% decrease in tumor burden (168 vs 254 ng/mL human K-light chain) and 50% less osteolytic area compared to vehicle treated mice bearing hMM (4.4 vs 10.2 mm2). Moreover, BT-GSI decreased serum CTX by 30%, but did not affect serum P1NP. Importantly, equimolar administration of the unconjugated BT molecule did not alter MM growth nor prevented bone loss in mice with established MM. In conclusion, these results show that bone-targeted Notch inhibition reduces MM growth and preserves bone mass in mice with established MM. Because BT-GSI shows bone specific Notch inhibition and lacks gut toxicity, it should circumvent the deleterious side effects that limit GSI use in patients. Thus, BT-GSI is a promising approach to inhibit MM growth and to prevent bone loss in MM patients. Citation Format: Adam J. Ferrari, Kevin McAndrews, Jessica H. Nelson, James T. Bell, Venkatesan Srinivasan, Frank H. Ebetino, Robert K. Boeckman Jr, G. David Roodman, Teresita Bellido, Jesus Delgado-Calle. Disruption of Notch Signaling targeted to the myeloma bone marrow microenvironment simultaneously inhibits tumor growth and prevents bone loss without inducing gut toxicity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 103.

Hemophagocytic Syndrome: Experience in a tertiary care centre

Introduction: Hemophagocytic syndrome also known as Hemophagocytic Lymphohistiocytosis (HLH) is a potentially fatal hyperinflammatory condition. It can be primary or a secondary disorder associated with a variety of underlying conditions. These disorders feature severe cytopenias due to uncontrolled hemophagocytosis and clinical symptoms result from disordered immune regulation and cytokine storm. Materials and Methods: The present study was done at the tertiary care centre attached to University Medical College in western India. Forty five patients with cytopenias who were suspected to have secondary HLH were included in this study. Clinical details and routine investigations, tests necessary to diagnose HLH i.e. Ferritin, Triglyceride, LDH, Fibrinogen levels were done. Bone marrow aspirate in these patients showed evidence of hemophagocytosis. Statistical analysis was done using the appropriate software and statistical tests. Results: Infection was the commonest cause associated with secondary HLH in our study. 95.5% patients had anaemia while 42.2% patients had fever along with other clinical manifestations. Elevated Serum Ferritin levels were found in 55.5% patients. 82.1% and 63.0% patients had elevated Lactate Dehydrogenase and elevated triglycerides levels respectively while only 35.6% patients had low fibrinogen levels. Higher levels of ferritin were associated with severe cytopenias and with poor outcome of the patients. PT and APTT were also deranged in a significant proportion of patients. We have also observed raised APTT values correlating with abnormal ferritin levels and cytopenias in our study. This could be because most of these cases were associated with sepsis. We found significant association of elevated serum Ferritin, Triglyceride and LDH levels with HLH. Conclusion: Hemophagocytic syndromes should be considered in unexplained cytopenias. A bone marrow aspiration or organ biopsy revealing hemophagocytosis along with Serum Ferritin, Triglycer

Fate of Barium Sulfate Nanoparticles Deposited in the Lungs of Rats

We have shown that barium [from BaSO4 nanoparticles (NPs)] was cleared from the lungs faster than other poorly soluble NPs and translocated mostly to bone. We now studied barium biokinetics in rats during Study 1: two-year inhalation exposure to 50 mg/m3 BaSO4 NP aerosols, and Study 2: single intratracheal (IT) instillation of increasing doses of BaSO4 NPs or BaCl2. Study 1 showed that lung barium content measured by inductively coupled plasma mass spectrometry increased during 360 days of BaSO4 NP aerosol exposures. An equilibrium was established from that time until 2 years. Barium concentrations in BaSO4-exposed animals were in the order (lungs > lymph nodes > hard bone > bone marrow > liver). In Study 2, there was an increase in lung barium post-IT instillation of BaSO4 NPs while barium from BaCl2 was mostly cleared by day 28. Transmission electron microscopy showed intact BaSO4 NPs in alveolar macrophages and type II epithelial cells, and in tracheobronchial lymph nodes. Using stimulated Raman scattering microscopy, specific BaSO4 Raman spectra were detected in BaSO4 NP-instilled lungs and not in other organs. Thus, we posit that barium from BaSO4 NPs translocates from the lungs mainly after dissolution. Barium ions are then incorporated mostly into the bone and other organs.

Comparative analysis of the conversion coefficient for internal dosimetry using different phantoms

There are many ways to estimate the absorbed dose for internal radionuclides. They are used to assess the stochastic risks associated with diagnostic applications of nuclear medicine as well as the deterministic risks to normal tissues associated with therapeutic nuclear medicine. The difference between these methods is the anatomical models used for the dosimetric calculation. The phantoms used by the International Commission on Radiological Protection (ICRP) Publication 89 are based on medical image data of the average population in Eastern Europe and North American. While the phantoms used in OLINDA/EXM software are based on the stylized anatomical models developed for the MIRD Committee of The Society of Nuclear Medicine in the 1960s. Its organs were mathematically based on descriptive and schematic materials from general anatomy references and were modeled after the prescriptions of the ‘Reference Man’ defined by ICRP-23. However, the difference between these phantoms and real patients can lead to a disparity of the real absorbed dose. This work aims to assess these two methods (OLINDA/EXM and ICRP-106) to an individualized dosimetric method. This individualized method consists of a voxels phantom constructed from computed tomography images from a patient with anatomical characteristics similar to those of ICRP-89’s reference man coupled with EGSnrc Monte Carlo code. The comparison of these methods was performed using the relative error. This is used to quantify the discrepancy between two sets of data. The relative errors were calculated between the conversion coefficients obtained by the three methods for skin, brain, lungs, liver, kidneys and cortical bone. The lowest relative error values were observed in the brain, liver, and lungs. This occurs because these organs have a higher uptake of the 18F-FDG and are recognized by the ICRP as source organs in this biokinetic model. Compared to OLINDA/EXM and to ICRP-106, the relative differences in these organs did not exceed 10%. In the kidneys, the significant relative error (>10%) can be justified due to the stage of elimination of the radiopharmaceutical at the time the image is taken, so that there is no way to perform comparative dosimetry in this organ. For the skin and bone organs, the significant relative error occurred due to non-representation of the whole human body by the patient-specific phantoms developed, unlike the phantoms used in dose estimation using OLINDA/EXM and ICRP-106. Thus, it is evident that dose estimation using reference models results in discrepancies in dose distribution, mainly in pediatric or obese patients in whom anatomical differences are greater.

Biomaterial-based endochondral bone regeneration: a shift from traditional tissue engineering paradigms to developmentally inspired strategies.

There is an urgent, clinical need for an alternative to the use of autologous grafts for the ever increasing number of bone grafting procedures performed annually. Herein, we describe a developmentally inspired approach to bone tissue engineering, which focuses on leveraging biomaterials as platforms for recapitulating the process of endochondral ossification. To begin, we describe the traditional biomaterial-based approaches to tissue engineering that have been investigated as methods to promote in vivo bone regeneration, including the use of three-dimensional biomimetic scaffolds, the delivery of growth factors and recombinant proteins, and the in vitro engineering of mineralized bone-like tissue. Thereafter, we suggest that some of the hurdles encountered by these traditional tissue engineering approaches may be circumvented by modulating the endochondral route to bone repair and, to that end, we assess various biomaterials that can be used in combination with cells and signaling factors to engineer hypertrophic cartilaginous grafts capable of promoting endochondral bone formation. Finally, we examine the emerging trends in biomaterial-based approaches to endochondral bone regeneration, such as the engineering of anatomically shaped templates for bone and osteochondral tissue engineering, the fabrication of mechanically reinforced constructs using emerging three-dimensional bioprinting techniques, and the generation of gene-activated scaffolds, which may accelerate the field towards its ultimate goal of clinically successful bone organ regeneration.

SAT-469 Empty Sella Making Big Changes: A Case of Acromegaly and Empty Sella Syndrome

Acromegaly is a condition defined by excess growth hormone (GH). The clinical features of acromegaly including overgrowth of many tissues including cartilage, bone, skin and visceral organs. It often times presents with coarsening of facial features and increased hat or ring size. Cardiovascular disease including hypertension with left ventricular hypertrophy and metabolic deficiencies including insulin resistance are also commonly seen as a result of the GH excess. The most common cause of acromegaly has been found to be GH secreting pituitary adenomas. MRI is generally sufficient to identify these lesions, but rarely a patient with symptoms of acromegaly will be found to have empty sella syndrome. Case: A 37 year old male, with a PMH of uncontrolled HTN presented to the emergency department after his wife found him on the floor, unconscious, foaming at the mouth, and shaking. He had an episode of urinary incontinence and was postictal for 20-30 minutes after the episode. In ED, he was hypertensive at 246/162, CT head showed right frontal intraparenchymal 1.2 cm hemorrhage and MRI brain showed various foci of hyperintensity compatible with hypertensive encephalopathy. He was also hypokalemic (2.9) with evidence of an AKI (BUN 27, Cr 1.73). He was admitted for further evaluation of suspected seizure. Upon further evaluation, the patient admitted to coarsening of facial features as noted on comparison of prior photographs. He also reported difficulties with his wedding ring fitting which he attributed to hand swelling. ROS was other negative with no vision changes or headaches. This sparked concern for a secondary cause of hypertension in the setting of clinical acromegaly. MRI brain was complicated by movement but revealed pituitary characteristics of empty sella syndrome. Insulin like growth factor 1 - 745. ECHO showed severe concentric left ventricular hypertrophy with aortic valve sclerosis and left atrial dilation. Renal Artery ultrasound showed no evidence of renal artery stenosis. The patient was subsequently scheduled for repeat MRI brain pituitary as outpatient under anesthesia to evaluate for possible surgical treatment for acromegaly. Discussion: This case demonstrates that empty sella syndrome does not warrant exclusion of acromegaly. GH secreting tumors can be present despite empty sella syndrome and acromegaly can even cause enlargement of the sella (?) . In these cases, the pituitary tissue lining the sella can be the source of excess GH. Upon case review, the mechanism remains unclear but empty sella syndrome may result from necrosis by infarction or from hemorrhage. Since no resectable mass is present in these cases, medical management with somatostatin analogues remains the only treatment that can be offered to these patients. It is important to keep acromegaly on the differential despite empty sella.

Aplidin (plitidepsin) is a novel anti-myeloma agent with potent anti-resorptive activity mediated by direct effects on osteoclasts.

Despite recent progress in its treatment, Multiple Myeloma (MM) remains incurable and its associated bone disease persists even after complete remission. Thus, identification of new therapeutic agents that simultaneously suppress MM growth and protect bone is an unmet need. Herein, we examined the effects of Aplidin, a novel anti-cancer marine-derived compound, on MM and bone cells. In vitro, Aplidin potently inhibited MM cell growth and induced apoptosis, effects that were enhanced by dexamethasone (Dex) and bortezomib (Btz). Aplidin modestly reduced osteocyte/osteoblast viability and decreased osteoblast mineralization, effects that were enhanced by Dex and partially prevented by Btz. Further, Aplidin markedly decreased osteoclast precursor numbers and differentiation, and reduced mature osteoclast number and resorption activity. Moreover, Aplidin reduced Dex-induced osteoclast differentiation and further decreased osteoclast number when combined with Btz. Lastly, Aplidin alone, or suboptimal doses of Aplidin combined with Dex or Btz, decreased tumor growth and bone resorption in ex vivo bone organ cultures that reproduce the 3D-organization and the cellular diversity of the MM/bone marrow niche. These results demonstrate that Aplidin has potent anti-myeloma and anti-resorptive properties, and enhances proteasome inhibitors blockade of MM growth and bone destruction.

Pathomorphological changes of the thymus of pigs at different stages of development of clinically expressed circovirus infection type ІІ

PCV2-infection of pigs plays an important role in the infectious pathology of pigs, having a significant impact on the economy of pig farms in different countries. Pathomorphological changes in the body of pigs with PCV2-infection occur moderately and in stages, as a result of the simultaneous launch of a set of mechanisms to counter the causative agent of the disease, resulting in the formation of a whole spectrum of reactive and pathological processes. The main “target” for PCV-2 is the immune system, and the multiplication of PCV-2 in the cells of the immune system leads to their death and development of immunodeficiency state. Thymus is the central organ of lymphocytopoiesis and imunopoiesis, in it occurs differentiation of all cellular forms of mature T-lymphocytes in the pre-T-lymphocyte stage, which migrate from the bone marrow to the bloodstream. The growth and development of the thymus, as well as the bone organs, is in direct interaction with the growth and development of the spleen, lymph nodes and is reflected in the structure of the interstitial connective tissue and lymphoid parenchyma. Purpose: determination of pathomorphological changes in the thymus of pigs at different stages of the development of clinically expressed PCV2-infection. Methods. The work was carried out in pig farms of Ukraine, with intensive technology of pig rearing, at the department of normal and pathological anatomy of agricultural animals and the Scientific and Research Center for Biosafety and Environmental Control of the Agroindustrial Complex Resources of Dnipro State Agrarian and Economic University. For pathomorphological studies, animals were selected with clinical signs of active PCV2‑infection (in 1 ml of whole blood of which contained more than 107 copies of the PCV-2 virus equivalent gene) and also piglets with positive optical density of specific antibodies (Ig G and Ig M) in serum blood. Pathomorphological changes were characterized by gradual exhaustion of the lymphoid parenchyma with a sharp decrease in the area of the cortical substance of the particles. Against the background of the degradation of the lymphoid parenchyma of the organ, there is a tendency to increase the relative area of the interstitial connective tissue, as well as the absolute size and number of thymic bodies, has been established.

Inhibition of Src Reduces Cortactin Phosphorylation and Transendothelial Migration of Acute Lymphoblastic Leukemia B cells

B‐cell acute lymphoblastic leukemia (B‐ALL) is the most common leukemia in children and adults. B‐ALL cells have the ability to extravasate and infiltrate bone marrow and organs such as lungs, testis and central nervous system (CNS). Dynamic actin cytoskeletal remodeling is needed to accomplish transendothelial migration. Cortactin is an actin‐binding protein which accumulates in lamellipodia and invadopodia and regulates neutrophil transendothelial migration during inflammation. Recently, we showed that cortactin is overexpressed in B‐cells of B‐ALL patients, and significantly correlates with bone marrow colonization, organ infiltration, drug resistance and disease relapse. Cortactin is a target for several posttranslational modifications such as phosphorylation and acetylation, being first discovered as a substrate of Src kinase and recently as substrate of the histone deacetylases SIRT1 and HDAC6. Phosphorylation of cortactin is thought to lead to lamellipodia and invadopodia protusion, whereas acetylation diminishes the affinity of cortactin to F‐actin, decreases cell migration capability, and may lead to nuclear translocation. However, it remains to be explored whether these modifications are required for the aggressiveness of leukemic B‐ALL cells. Thus, in this study, we analyzed the importance of such modifications for transendothelial migration and bone marrow organoid colonization. A MTT (3‐(4, 5‐dimethylthiazolyl‐2)‐2, 5‐diphenyltetrazolium bromide) assay was performed to determine effects of certain pharmacological inhibitors of posttranslational modifications on cell viability. To this end, REH cells were incubated with the indicated pharmacological compounds for 24 hours at different concentrations (50 to 150 mM). The IC50 value for PP2 (Src inhibitor) was 190.82 mM, for EX‐527 (SIRT1 inhibitor) was 190.94 mM, for Tubacin (HDAC6 inhibitor) was 41.39 mM, and for Tubastatin‐A (HDAC6 inhibitor) was 94.09 mM. Importantly, after 20 min of treatment of only REH cells with PP2 at 20 μM, REH cells transmigrated significantly less across CXCL12‐stimulated HUVEC monolayers, which may be due to a reduction of phosphorylated cortactin that impairs cytoskeletal remodeling needed for migration of the cells. Taken together, these results suggest that cortactin phosphorylation may be needed by leukemic B cells to achieve transmigration and may reveal cortactin as a potential new therapeutic target for high risk B‐ALL patients to prevent disease relapse.Support or Funding InformationCONACyTThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

Pharmacological Inhibition of NF\u03baB Reduces Prostate Cancer Related Osteoclastogenesis In Vitro and Osteolysis Ex Vivo

NFκB is implicated in cancer and bone remodelling, and we have recently reported that the verified NFκB inhibitor Parthenolide (PTN) reduced osteolysis and skeletal tumour growth in models of metastatic breast cancer. Here, we took advantage of in vitro and ex vivo bone cell and organ cultures to study the effects of PTN on the ability of prostate cancer cells and their derived factors to regulate bone cell activity and osteolysis. PTN inhibited the in vitro growth of a panel of human, mouse and rat prostate cancer cells in a concentration-dependent manner with a varying degree of potency. In prostate cancer cell—osteoclast co-cultures, the rat Mat-Ly-Lu, but not human PC3 or mouse RM1-BT, enhanced RANKL stimulated osteoclast formation and PTN reduced these effects without affecting prostate cancer cell viability. In the absence of cancer cells, PTN reduced the support of Mat-Ly-Lu conditioned medium for the adhesion and spreading of osteoclast precursors, and survival of mature osteoclasts. Pre-exposure of osteoblasts to PTN prior to the addition of conditioned medium from Mat-Ly-Lu cells suppressed their ability to support the formation of osteoclasts by inhibition of RANKL/OPG ratio. PTN enhanced the ability of Mat-Ly-Lu derived factors to increase calvarial osteoblast differentiation and growth. Ex vivo, PTN enhanced bone volume in calvaria organ—Mat-Ly-Lu cell co-culture, without affecting Mat-Ly-Lu viability or apoptosis. Mechanistic studies in osteoclasts and osteoblasts confirmed that PTN inhibit NFκB activation related to derived factors from Mat-Ly-Lu cells. Collectively, these findings suggest that pharmacological inhibition of the skeletal NFκB signalling pathway reduces prostate cancer related osteolysis, but further studies in the therapeutic implications of NFκB inhibition in cells of the osteoblastic lineage are needed.

Pro-inflammatory Cytokines and Osteocytes.

An elevated level of pro-inflammatory cytokines in inflammatory conditions causes bone loss and disrupts vital organ function. Osteocytes comprise > 95% of the cellular component in bone tissue, produce a range of cytokines and signaling molecules, and influence bone and other organ function. In this review, we hypothesized that an elevated level of pro-inflammatory cytokines in inflammatory conditions affects osteocyte survival and function thereby possibly amplifying inflammation, and causing bone loss and non-bone clinical complications. Several studies have reported that the elevated level of pro-inflammatory cytokines in inflammatory conditions alters osteocyte mechanosensitivity, causes osteocyte apoptosis, and modulates osteocyte-derived production of various inflammatory cytokines and signaling molecules. Cytokines and signaling molecules released from osteocytes affect surrounding bone cells and distant organ function in a paracrine and endocrine fashion. Inflammatory diseases including diabetes, chronic kidney disease, rheumatoid arthritis, and periodontitis affect osteocyte survival and function, and upregulate osteocyte-derived expression of sclerostin, RANKL, TNFα, FGF23, DKK1, and other signaling molecules.