Modulation of Vacuolar pH Is Required for Replication of Edwardsiella ictaluri in Channel Catfish Macrophages

Previous in vitro work demonstrated that Edwardsiella ictaluri produces an acid-activated urease that can modulate environmental pH through the production of ammonia from urea. Additional work revealed that expression of the E. ictaluri type III secretion system (T3SS) is upregulated by acidic pH. Both the urease and the T3SS were previously shown to be essential to intracellular replication. In this work, fluorescence microscopy with LysoTracker Red DND-99 (LTR) indicated that E. ictaluri-containing vacuoles (ECV) became acidified following ingestion by head kidney-derived macrophages (HKDM). In vivo ratiometric imaging demonstrated a lowered ECV pH, which fell to as low as pH 4 but subsequently increased to pH 6 or greater. Inhibition of vacuolar H⁺-ATPases by use of the specific inhibitor bafilomycin A₁ abrogated both ECV acidification and intracellular replication in HKDM. Failure of an E. ictaluri urease knockout mutant to increase the ECV pH in the in vivo ratiometric assay suggests that ammonia produced by the urease reaction mediates the pH increase. Additionally, when the specific arginase inhibitor l-norvaline was used to treat E. ictaluri-infected HKDM, the ECV failed to neutralize and E. ictaluri was unable to replicate. This indicates that the HKDM-encoded arginase enzyme produces the urea used by the E. ictaluri urease enzyme. Failure of the ECV to acidify would prevent both upregulation of the T3SS and activation of the urease enzyme, either of which would prevent E. ictaluri from replicating in HKDM. Failure of the ECV to neutralize would result in a vacuolar pH too low to support E. ictaluri replication.     

Macrophages and mesenchymal stromal cells support survival and proliferation of multiple myeloma cells

Multiple myeloma (MM) is characterized by almost exclusive tropism of malignant cells for the bone marrow (BM) milieu. The survival and proliferation of malignant plasma cells have been shown to rely on interactions with nonmalignant stromal cells, in particular mesenchymal stromal cells (MSCs), in the BM microenvironment. However, the BM microenvironment is composed of a diverse array of cell types. This study examined the role of macrophages, an abundant component of BM stroma, as a potential niche component that supports malignant plasma cells. We investigated the proliferation of MM tumour cell lines when cultured alone or together with MSCs, macrophages, or a combination of MSCs and macrophages, using the carboxyfluorescein succinimidyl ester assay. Consistently, we observed increased proliferation of MM cell lines in the presence of either MSCs or macrophages compared to cell line-only control. Furthermore, the combined co-culture of MSCs plus macrophages induced the greatest degree of proliferation of myeloma cells. In addition to increased proliferation, MSCs and macrophages decreased the rate of apoptosis of myeloma cells. Our in vitro studies provide evidence that highlights the role of macrophages as a key component of the BM microenvironment facilitating the growth of malignant plasma cells in MM.     

Round Pendant Around the Neck–Thyroid. A Review

The rare situation of thyroid stone is discussed with literature review and case report. A case of isolated solitary stone of the thyroid is documented here. There are incidences of calcification in the thyroid gland commonly associated with carcinoma thyroid and multinodular goiter. But solitary stone of thyroid is reported rarely and one such case is reported from India. The possibility of malignancy is high, in case of calcification of thyroid swellings. Hence, isolated calcification should be surgically treated even if fine needle aspiration cytology is negative for malignancy.     

The Influence of the Elemental Composition,Crystal Structure,and Grain Structure of the Ferro-Piezoceramics of Various Degrees of the Ferro-Hardness on the Stability of the Polarized State

Ferro-piezoceramic materials (FPCM) with different degrees of ferrohardness were fabricated by double solid-phase synthesis followed by the sintering technique using hot pressing method. The X-ray studies carried out in a wide temperature range showed that with increasing temperature, each of the studied FPCM undergoes a series of phase transformations, accompanied by a change in the symmetry of the unit cell. In this case, near the phase transition to the nonpolar cubic phase, in each of the FPCM, the formation of a fuzzy symmetry region is observed, which is characterized by weak distortions and temperature–time instability of the crystal structure. The study of the piezoelectric modulus d₃₃ in the quasi-static regime as a function of temperature made it possible to reveal the different nature of its behavior in materials of various degrees of ferrohardness. It was shown that the conservation of the state in ferrosoft materials above the Curie temperature is associated with the relaxation nature of the change in their properties, the existence of a region of fuzzy symmetry (noncubic phase) in them above the Curie temperature, and increased inertia of the system. The expediency of taking into account the presented results in the development of electromechanical converters based on FPCM of various degrees of ferrohardness, operated under temperature effects, including cyclic ones, was shown.     

Preparation of 3,5-diarylsubstituted 5-hydroxy-1,5-dihydro-2H-pyrrol-2-ones via base-assisted cyclization of 3-cyanoketones

A convenient preparative method is developed allowing for expeditious assembly of 3,5-diarylsubstituted 5-hydroxy-1,5-dihydro-2H-pyrrol-2-ones from routinely available inexpensive synthetic precursors. These compounds could not be prepared via the previously known protocols, as 2-aminofuran derivatives were produced instead.

The highly efficient oxidative cyclization of 1,3-diarylsubstituted 3-cyanoketones yielded 5-hydroxy-1,5-dihydro-2H-pyrrol-2-ones.     

Involvement of adenylate cyclase and tyrosine kinase signaling pathways in response of crayfish stretch receptor neuron and satellite glia cell to photodynamic treatment

Neuroglial interactions are most profound during development or damage of nerve tissue. We studied the responses of crayfish stretch receptor neurons (SRN) and satellite glial cells to photosensitization with sulfonated aluminum phthalocyanine Photosens. Although Photosens was localized mainly in the glial envelope, neurons were very sensitive to photodynamic treatment. Photosensitization gradually inhibited and then abolished neuron activity. Neuronal and glial nuclei shrank. Some neurons and glial cells lost the integrity of the plasma membrane and died through necrosis after the treatment. The nuclei of other glial cells but not neurons become fragmented, indicating apoptosis. The number of glial nuclei around neuron soma increased, probably indicating proliferation for enhanced neuron protection. Adenylate cyclase (AC) inhibition by MDL-12330A, or tyrosine kinase (TK) inhibition by genistein, shortened neuron lifetime, whereas AC activation by forskolin or protein tyrosine phosphatases (PTP) inhibition by sodium orthovanadate prolonged neuronal activity. Therefore, cAMP and phosphotyrosines produced by AC and TK, respectively, protected SRN against photoinactivation. AC inhibition reduced photodamage of the plasma membrane and subsequent necrosis in neuronal and glial cells. AC activation prevented apoptosis in photosensitized glial cells and stimulated glial proliferation. TK inhibition protected neurons but not glia against photoinduced membrane permeabilization and subsequent necrosis whereas PTP inhibition more strongly protected glial cells. Therefore, both signaling pathways involving cAMP and phosphotyrosines might contribute to the maintenance of neuronal activity and the integrity of the neuronal and glial plasma membranes. Adenylate cyclase but not phosphotyrosine signaling pathways modulated glial apoptosis and proliferation under photooxidative stress.     

Assembly of large-area,highly ordered,crack-free inverse opal films

Whereas considerable interest exists in self-assembly of well-ordered, porous “inverse opal” structures for optical, electronic, and (bio)chemical applications, uncontrolled defect formation has limited the scale-up and practicality of such approaches. Here we demonstrate a new method for assembling highly ordered, crack-free inverse opal films over a centimeter scale. Multilayered composite colloidal crystal films have been generated via evaporative deposition of polymeric colloidal spheres suspended within a hydrolyzed silicate sol-gel precursor solution. The coassembly of a sacrificial colloidal template with a matrix material avoids the need for liquid infiltration into the preassembled colloidal crystal and minimizes the associated cracking and inhomogeneities of the resulting inverse opal films. We discuss the underlying mechanisms that may account for the formation of large-area defect-free films, their unique preferential growth along the 〈110〉 direction and unusual fracture behavior. We demonstrate that this coassembly approach allows the fabrication of hierarchical structures not achievable by conventional methods, such as multilayered films and deposition onto patterned or curved surfaces. These robust SiO₂ inverse opals can be transformed into various materials that retain the morphology and order of the original films, as exemplified by the reactive conversion into Si or TiO₂ replicas. We show that colloidal coassembly is available for a range of organometallic sol-gel and polymer matrix precursors, and represents a simple, low-cost, scalable method for generating high-quality, chemically tailorable inverse opal films for a variety of applications.     

Radiosynoviorthesis (RSO): influencing factors and therapy monitoring

Objective  To evaluate the effectiveness of radiosynoviorthesis (RSO) in relation to joint type and underlying disease by both self-assessment of patients and scintigraphic assessment to determine conditions under which RSO might be preferable to the sole intra-articular corticoid injection. Methods  Radiosynoviorthesis was performed on 136 patients for 424 joints [242 small, 130 medium-sized, and 52 large joints; 313 with rheumatoid arthritis (RA) and 111 with osteoarthritis (OA)]. The success of RSO was evaluated after 12 months by patients’ estimation, and in 35 patients for 157 joints additionally by two-phase bone scintigraphy. The relative change in the scintigraphic uptake was compared with the patients’ estimation. Results  The subjectively estimated success rates for the small, medium-sized, and large joints were 89% (215/242), 86% (112/130), and 79% (41/52), and for RA and OA 89% (280/313) and 79% (88/111), respectively. The scintigraphically determined response rates for small and medium-sized joints were 81% (86/106) and 69% (35/51), respectively. There was a mismatch between patients’ assessment and scintigraphic assessments in 18% (28/157) with 6 false-negative and 22 false-positive estimations using scintigraphy as the standard of reference. Conclusions  The success of RSO is higher in patients with RA than in patients with OA. For the finger, ankle, and wrist joints in RA, RSO is so promising that we would like to advocate its preference over the sole intraarticular corticoid injection. Perfusion bone scintigraphy can be used for therapy monitoring and earlier switching to RSO by showing that other therapies have failed.