Mantle Zone Research Articles

Spatial and temporal mush heterogeneity during eruptions recorded in clinopyroxene from the 2021 paroxysms at Mt. Etna, Italy

Textural and compositional zoning of volcanic minerals archives pre-eruptive magma processes. Crystals erupted simultaneously may be sampled from different regions of the plumbing system and hence record variable histories due to complex magma dynamics. In addition, crystals erupted throughout the course of an eruption may record temporal variations in the plumbing system. To resolve mush variability on both spatial and temporal scales, we investigate clinopyroxene erupted during a series of paroxysmal episodes between February–April 2021 at Mt. Etna, Italy. Using a combination of high-resolution geochemical techniques, we observe that Cr enrichments in clinopyroxene mantle zones, grown upon eruption-triggering mafic rejuvenation, exhibit both temporal and spatial (sample-scale) variability. Temporal variability correlates with changes in glass compositions, attesting to the ability of clinopyroxene to track magma maficity throughout an eruption. Spatial variability, indicated by the scatter of Cr concentrations, is greatest for the first event and lowest for the final paroxysm. In conjunction with core textures, degree of sector enrichment and thermobarometry, our data suggest that the onset of the paroxysms was preceded by the remobilisation of a mid-crustal clinopyroxene mush (534 ± 46 MPa) by hot, mafic magma causing variable resorption of mush-derived crystal cores. Towards the end of the eruption, waning magma supply led to less efficient mush remobolisation and mixing, resulting in homogenous crystal populations. Our results highlight that clinopyroxene Cr contents and sector enrichment can be used to track mafic rejuvenation and magma evolution throughout eruptions, while also reflecting spatial heterogeneities within the plumbing system.

Petrogenesis and an Evaluation of the Melting Conditions of the Late Permian ELIP Picrites, SW China: Constraints Due to Primary Magma and Olivine Composition

The late Permian Emeishan large igneous province (ELIP) in SW China is a melting product of the Emeishan mantle plume. Recently, it has been debated whether peridotite or pyroxenite is the dominant lithology of the mantle source in the ELIP. To address this, systematic analyses of bulk-rock and coexisting spinel and olivine compositions were conducted on picrites from Lijiang–Yongsheng, Dali–Binchuan, Yumen, Muli, and Ertan. The ELIP picrites exhibit positive TiO2–CaO and negative MgO–CaO correlations, as well as low FC3MS values (−0.24–0.1), supporting a peridotite-dominated mantle source. This lithology of the mantle source is also supported by the high 100 × Mn–Fe (1.43–1.73) and Mn–Zn (13.6–18.4) values but low 10,000 × Zn–Fe (8.0–12.7) ratios of the olivine phenocrysts. The estimated mantle potential temperature for Lijiang, Yongsheng, Yumen–Ertan, Muli, and Dali–Binchuan picrites decreased away from Lijiang and Yongsheng, suggesting that the Lijiang and Yongsheng areas were the center of the ELIP. The Lijiang–Yongsheng primary magma shows similar SiO2 content but lower Al2O3 contents (average of 8.24 wt.%) and higher MgO contents (average of 21.42 wt.%) than those of Dali–Binchuan primary magma (Al2O3: 9.86 wt.%; MgO: 19.02 wt.%). Also considering the high Gd–Yb (average of 3.05) and La–Yb (average of 14.61) ratios and mantle potential temperature (average of 1599 °C), we proposed that Lijiang–Yongsheng lavas are produced via the melting of a garnet–peridotitic mantle. In contrast, the Dali–Binchuan lavas with low Gd–Yb (average of 1.91) and La–Yb (average of 5.88) ratios can be explained by their formation in the garnet–spinel transition zone of a peridotitic mantle. The Yumen–Ertan primary magma displays similar mantle potential temperature (average of 1600 °C), Al2O3 and FeO content, and Gd–Yb ratios to those of Lijiang–Yongsheng lavas, indicating that YumenvErtan primary magma may be attributed to the partial melting of garnet with minor peridotite. Therefore, heterogeneous plume-head mantle sources lead to the evaluation of melting conditions of the late Permian ELIP picrites.

Chrome incorporation in high-pressure Fe–Mg oxides

Abstract. The occurrence of Cr-bearing oxide phases as inclusions in diamonds and in extraterrestrial materials has the potential to serve as an indicator of formation conditions. However, such an application requires detailed knowledge of phase stabilities and the influence that Cr may have on its stability. To this end, the incorporation of Cr in high-pressure post-spinel Fe–Mg oxide phases was experimentally investigated at pressures of 14–22 GPa and temperatures between 1100 and 1600 °C using a multi-anvil press. We find that neither the Fe3Cr2O6 nor the Mg3Cr2O6 endmember composition is stable over the expected range of pressure and temperature where Fe5O6 itself is known to be stable. Further experiments along the Fe32+Fe23+O6–Fe32+Cr2O6 binary indicate only small amounts of Cr substitution are possible: ∼ 0.12 cations Cr per formula unit or ∼ 6 mol % Fe32+Cr2O6 component. In contrast, complete solid solution is apparent across both the Fe22+(Cr,Fe3+)2O5 and the Mg2(Cr,Fe3+)2O5 binaries, and there are indications of complete solution in the entire (Mg,Fe2+)2(Cr,Fe3+)2O5 quaternary system. The O5-structured phase usually coexists with (Fe,Mg)O. At 16–20 GPa, a post-spinel phase with O4 stoichiometry was occasionally encountered, having either a modified Ca-ferrite- (mCF-FeCr2O4) or a Ca-titanate-type (CT-MgCr2O4) structure. In one high-temperature experiment at 1600 °C, an unquenchable Mg-rich phase with a reconstructed Mg4Fe23+O7 stoichiometry occurred together with Mg2(Cr,Fe3+)2O5. In one experiment at 1100 °C and 16 GPa with a bulk composition of Mg2(Cr0.6,Fe0.43+)2O5, an assemblage of O5 phase + eskolaite–hematite solid solution + periclase was obtained together with minor amounts of the CT-type phase and a β-(Cr,Fe)OOH phase. The occurrence of these two minor phases in this low-temperature experiment is an indicator of variable reaction kinetics amongst the starting materials, which caused chemical heterogeneities to develop at the onset of the experiment. The structural systematics of Fe22+(Cr,Fe3+)2O5 and (Fe2+,Mg)2(Cr,Fe3+)2O5 solid solutions were investigated. It is notable that the Fe3+ and Cr endmembers have somewhat different crystal structures, belonging to space groups Cmcm (no. 63) and Pbam (no. 55), respectively. The phase transition occurs around the midpoint of the Fe3+–Cr joins. In spite of complexities in the behavior of the unit-cell parameters, the variation in molar volume with composition deviates only slightly from linearity. Wüstite and periclase coexisting in our experiments reveal the incorporation of up to 9 wt % and 25 wt % Cr2O3, respectively. This is consistent with the minor Cr contents reported for some ferropericlase inclusions in natural diamond. The limited solubility of other cations in Fe5O6 limits the likelihood of it being an accessory phase in the Earth's deep upper mantle and transition zone, except in Fe-rich environments. In contrast, the O5 phase appears to be more flexible in accommodating a range of divalent and trivalent cations, suggesting that this phase is more likely to be stabilized, potentially where redox reactions related to diamond formation occur.

The clinicopathologic features of unicentric Castleman disease in the children's neck

Objective:To investigate the clinical features, imaging findings, pathological phenotype, treatment and prognosis of unicentric Castleman disease in the children's neck, in order to improve the understanding of CD among Otolaryngology Head and Neck Surgery. Methods:Retrospective cross-sectional, observational study was undertaken in Kunming Children's Hospital, from the archival data between January July 2015 and June 2020. Only 6 cases of CD were identified after studying the histomorphological characteristics and neck mass diagnosed. The imaging and pathological features were summarized and the pathogenesis was discussed. Results:Among the 6 cases of Castleman disease, five were male and one was female. Histopathology: Five cases were hyaline vascular subtype, one was mixed type. The uniform clinicopathologic features seen in all hyaline vascular subtype of CD included atrophic germinal centre with lymphocyte depletion, concentric rings of small lymphocytes, increased vascularity and predominance of high endothelial vessels in interfollicular region. Twinning, in which two or more germinal centers are combined and surrounded by lymphocytes in the mantle zone was observed in two cases with lollipop pattern at the same time. All the cases underwent complete surgical resection, the median follow-up time was 48 months（26, 84）, both of them had good prognosis. Conclusion:Most cases of unicentric type CD in children are diagnosed late, which is clinical showed by painless lymphadenopathy. The most common pathological type is hyaline vascular. The overall prognosis of surgical treatment was good.

Morphological and functional spleen development in crossbreed rabbits

The accelerated growth of muscle mass in productive broiler breeds is often associated with delayed organ development of integral body systems, particularly the immune structures. The spleen is the largest secondary immune organ in the mammalian body and is responsible for initiating immune responses to blood-borne antigens. It can only perform this function successfully if all of its tissue components are fully morphologically and functionally mature. The spleen was studied in meat production rabbits (early maturing crossbreed Hyplus) at 1, 10, 20, 30, 60 and 90 days of age. Morphological studies included anatomical dissection, clarification of topography, determination of mass parameters, preparation of smears and histological sections. Spleen histological sections were stained with haematoxylin and eosin, according to Van Gieson, and impregnated with silver nitrate, followed by microscopy. Qualitative and quantitative indicators of spleen cellular and tissue component development were determined using ImageJ software. It was found that in crossbred rabbits the topography of the spleen corresponds to general anatomical principles of localisation, has a fixed place and is an anatomically formed organ. In day-old animals, the histological differentiation of the spleen is limited to the connective tissue stroma and the parenchyma. The organ's parenchyma is formed by reticular tissue, with hematopoietic and lymphoid cells among the cells, without differentiation into white and red pulp. In 10-day-old rabbits, the white pulp is represented by the periarterial lymphatic sheath (PALS) and marginal zones. Single primary lymphoid nodules without germinal centres are seen in the spleen from 20 days of age. By 30 days of age, the white splenic pulp has all the major structural and functional zones, including formed lymphoid nodules with germinal centres and mantle zones. During the second and third months of life, the spleen gradually increases the relative area of all white pulp functional zones, reaching a maximum at 90 days of age. In productive rabbits, the cellular composition of the splenic white pulp is represented by lymphocytes (small, medium, large), reticular cells, macrophages and plasma cells. During postnatal ontogenesis, the number of small lymphocytes increases in all white pulp functional zones, reaching maximum values in 90-day-old animals. On the contrary, the relative number of medium and large lymphocytes decreases. The number of reticulocytes in the periarterial lymphatic sheath and lymphoid nodules zones does not change significantly, and in the marginal zone it decreases substantially by the end of the study. The results of determining the timing of morphological and functional maturation of immunocompetent structures in the spleen of meat rabbits are of great biomedical and economic importance. They will serve as a control for comparing changes in rabbit spleen lymphoid tissues during the development of pathological processes, as well as under the influence of external factors.

Mantle Cell Lymphoma- A Rare Occurrence: Case Report

Mantle Cell Lymphoma (MCL) is a relatively uncommon yet distinct type of malignant lymphoma whose clinical and pathological characterization has been limited by the small numbers of cases published to date. It comprises 3-7% of all Hodgkin’s lymphoma cases, with a median diagnosis age of 68 years. Based on immunophenotypic and molecular data, MCL is a neoplasm composed of cells resembling those residing in follicular mantle zones. Although MCL usually presents as advanced disease some patients may present with more limited (stages I-I) disease. We present the case of a 41-year-old male who exhibited generalized lymphadenopathy and hepatosplenomegaly. Peripheral smear showed absolute lymphocytosis and the bone marrow biopsy and flow cytometry identified the condition as mantle cell lymphoma. The patient’s management required a multidisciplinary approach, incorporating haematological, molecular, and genetic evaluations. Treatment included hyper-CVAD chemotherapy. Proteasome inhibitors (Bortezomib), mTOR inhibitors (Temsirolimus), and immunomodulatory drugs (Lenalidomide) have recently been added to the treatment options in MCL.This case underscores the significance of comprehensive evaluation and customized therapeutic strategies and re looking an old diagnosis in managing complex haematological disorders.

The Sentient Propagation-Reactive B Cell-Rich Lymphoid Proliferation

Reactive B cell-rich lymphoid proliferation is a heterogeneous group of non-neoplastic lymphoid cell proliferation recapitulating diverse B cell lymphomas. The lesion is commonly categorized as nodal and extra-nodal follicular proliferations, nodal and extra-nodal nodular proliferations or nodal and extra-nodal immunoblastic proliferations. Florid follicular hyperplasia is comprised of quantifiably enhanced, disseminated primary and secondary lymphoid follicles with irregular outlines. Hyperplastic Germinal Centres (GCs) are comprised of admixed centroblasts and centrocytes, reactive T cells, Follicular Dendritic Cells (FDCs) and tingible body macrophages. Lymph node architecture depicts lymphoid follicles comprised of cells expressing B cell antigens wherein primary follicles are pre-eminently constituted of small lymphocytes BCL2+, BCL6- and CD10- immune reactivity. Progressive Transformation of Germinal Centre (PTGC) is constituted of singular or few enlarged lymphoid follicles of 4x to 5x magnitude wherein mantle zone cells display extensive invagination into adjacent germinal centres. Hyaline Vascular Castleman’s Disease (HVCD) delineates innumerable lymphoid follicles confined to the lymph node cortex and medulla or diverse extramedullary sites.

Mantle Cell Lymphoma in the Oral Cavity: Exploring the Differential Microscopic Diagnosis of a Rare Case.

Mantle cell lymphoma (MCL) is a rare subtype of B-cell non-Hodgkin's lymphoma (NHL), which generally has an aggressive course. Its pathophysiology seems to be related with the malignant transformation of B-cell mantle zone lymphocytes due to the CCND1 rearrangement. The occurrence of MCL in the oral cavity is especially rare. In this report, we present an exceptional case of oral MCL diagnosed in the palate in a 56-year-old male patient, highlighting its distinct morphological and immunohistochemical features that may assist in the accurate diagnosis.

Characteristics of Earthquake Mechanisms Along the Andaman - Nicobar Region derived from Bayesian Moment Tensor Inversion

Abstract Earthquake activities in the Andaman - Nicobar region are generated mainly by several active faults and an active subduction zone that can activate multiple hypocenter clusters. Therefore, studying the seismotectonic process from source mechanism analysis using moment tensor inversion is essential. In this research, we applied a stochastic Bayesian inversion using Grond, a framework tool for moment tensor (MT) inversion, to characterize the earthquake mechanisms and the most appropriate centroid locations. Procedurally, several of the largest earthquakes with a moment magnitude Mw > 5.5 from 2007 to 2023 were analyzed using the regional and teleseismic networks up to 2000 km from the epicenter based on 1 Hz green function model and azimuthal gap coverage. We applied 10,000-30,000 iterations of inversions with 300 bootstrap chains for a stable result. The low-frequency bandpass with a range of 0.007 - 0.03 Hz was chosen for the inversion process. There were 17 solutions for earthquake mechanisms with good misfit values of < 0.65. Based on the division of the 5 clusters with the highest seismicity, the selected earthquakes’ source mechanism is dominated by strike-slip and oblique faulting. The results were compared with existing data catalogs showing differences in hypocentre and fault orientation direction, particularly for strike-slip earthquakes in the shallow crust and mantle zones.

Dynamic Component of the Asthenosphere: Lateral Viscosity Variations Due To Dislocation Creep at the Base of Oceanic Plates

AbstractThe asthenosphere is commonly defined as an upper mantle zone with low velocities and high attenuation of seismic waves, and high electrical conductivity. These observations are usually explained by the presence of partial melt, or by a sharp contrast in the water content of the upper mantle. Low viscosity asthenosphere is an essential ingredient of functioning plate tectonics. We argue that a substantial component of asthenospheric weakening is dynamic, caused by dislocation creep at the base of tectonic plates. Numerical simulations of subduction show that dynamic weakening scales with the surface velocity both below the subducting and the overriding plate, and that the viscosity decrease reaches up to two orders of magnitude. The resulting scaling law is employed in an apriori estimate of the lateral viscosity variations (LVV) below Earth's oceans. The obtained LVV help in explaining some of the long‐standing as well as recent problems in mantle viscosity inversions.

Mapping geodetically inferred Antarctic ice surface height changes into thickness changes: a sensitivity study

Abstract. Determining recent Antarctic ice volume changes from satellite altimeter measurements of ice surface height requires a correction for contemporaneous vertical crustal deformation. This correction must consider two main sources of crustal deformation: (1) ongoing glacial isostatic adjustment (GIA), that is, the deformational, gravitational, and rotational response to Late Pleistocene and Holocene ice and ocean mass changes and (2) modern ice mass change. In this study, we seek to quantify the uncertainties associated with each of these corrections. Corrections of ice surface height changes for correction 1 have generally involved the adoption of global models of GIA defined by some preferred combination of ice history and mantle viscoelastic structure. We have computed the GIA correction generated from a coupled ice sheet–sea level model and a realistic Earth model incorporating three-dimensional viscoelastic structure. Integrating the difference between this correction and those from recent GIA analyses widely adopted in the literature yields an uncertainty in total present-day ice volume change equivalent to approximately 10 % of Antarctic ice mass loss inferred for the period 2010–2020. This reinforces earlier work indicating that ice histories characterized by relatively high excess ice volume at the Last Glacial Maximum may be introducing a significant error in estimates of modern melt rates. Regarding correction 2, a spatially invariant scaling has commonly been used to convert GIA-corrected ice surface height changes obtained from satellite altimetry to ice volume estimates. We adopt modeling results based on a projection of Antarctic ice mass change over the period 2015–2055 to demonstrate a spatial variability in the scaling of up to 10 % across the ice sheet. Furthermore, using these calculations, we find a systematic error of ∼ 3 % in the projected net ice volume change, with most of the difference arising in areas of West Antarctica above mantle zones of low viscosity.

Clinical Approach to Advanced Mantle Cell Lymphoma: A Detailed Case Analysis

Mantle cell lymphoma (MCL) is a rare and aggressive subtype of non-Hodgkin lymphoma (NHL) originating from cells in the mantle zone. Herein, we present a case report of a 49-year-old male patient diagnosed with stage VI MCL, illustrating various diagnostic methods and procedures utilized in his evaluation. The patient presented with progressively enlarging cervical lymph nodes, fatigue, weight loss, anorexia, chronic diarrhea, abdominal pain, and rectal bleeding. Clinical examination revealed cutaneomucosal pallor, tachycardia, expiratory polypnea, bilateral jugulocarotid adenopathies, and splenomegaly. Laboratory investigations showed normocytic normochromic anemia, hyperleukocytosis, lymphocytic predominance, and thrombocytopenia. Peripheral blood smear analysis indicated a lymphoproliferative disorder, confirmed by flow cytometry revealing monotypic lymphoid cells. Bone marrow biopsy showed hypoplastic marrow with atypical cells. Immunohistochemistry confirmed mantle cell lymphoma localization. Subsequent thoraco-abdomino-pelvic CT scan revealed mediastinal and abdominal adenopathy with splenomegaly, leading to a diagnosis of stage IV MCL. The case highlights the importance of early and comprehensive diagnostic approaches in MCL management.

Geochemistry and origin of the Late Carboniferous ultramafic, mafic, and felsic plutonic rocks (NW Iran)

The Late Carboniferous Gharabagh-Mamkan-Mingol plutonic complex (GMMP) consists of a variety of ultramafic, mafic, felsic intrusive rocks, including the 325–315 Ma Gharabagh gabbroic, granitic, and monzonitic rocks and Mamkan-Mingol 320–315 Ma massive appinites (hornblende-rich gabbros) and 300–295 Ma layered mafic-ultramafic (gabbro, appinitic gabbro, and appinite) rocks in the northwestern Sanandaj-Sirjan zone, Iran. The relationships between various rock types in the plutonic complex are unknown. To address these issues, we conducted a detailed petrologic and geochemical study of the complex, and its country rocks.The abundance of major and trace elements and isotopic ratios of 87/86Sr (0.70379–0.70428) and 143/144Nd (0.51228–0.51245) systems showed that the Gharabagh gabbros formed from a metasomatized amphibole-bearing spinel lherzolite from an ancient subduction-modified mantle source with OIB characteristics including high contents of light rare earth elements (LREEs), Ti, Nb, Ta, and Ba, as well as low concentrations of Sr, Hf, and Zr. The geochemical data show that monzonites had high concentrations of LREEs, Ba, U, K, Hand Zr, and the low contents of Th, Nb, Ta, Sr, P, and HREEs and Eu-positive anomalies and originated from the melting of the continental crustal base in the subducted mantle wedge. The granites are similar to monzonites, with their difference being in the high concentrations of Th and Eu-negative anomalies. Combining petrographic, petrological, geochemical, and isotopic data suggests that Gharabagh plutonic rocks were formed as a result of Paleo-Tethys slab break-off, and slab sinking, during trans-tensional collision between the Central Iranian microplate and Gondwanaland during the Late Carboniferous. As a result of this event, decompression melting began in the upwelling mantle, coeval with the formation of the pull-apart basin, during major strike-slip faulting, leading to a hydrous mafic melt with about 10–12% partial melting.The Mamkan-Mingol massive and layered masses have a tholeiitic affinity. The Mamkan-Mingol rocks are characterized by different trace element patterns, especially in the concentrations of REEs and high field strength elements (HFSEs) such as Nb, Ta, Hf, Zr, and P and large-ion lithophile elements (LILEs) such as Th, U, Sr, K, Rb, and Ba. The massive and layered rocks mostly show a variably developed negative anomaly in HFSEs, and widely varying ratios of (La/Yb)n (1.0–5.2). Massive appinites and layered gabbros of GMMP originated due to different partial melting in the upwelling zone of metasomatized OIB-like amphibole-bearing spinel lherzolite and a less hydrous- to dry upwelling mantle zone, respectively, in an environment associated with the initiation of rifting, where the remnants of the Paleo-Tethys subducted slab plunges deep into the mantle. Contrasting Nd isotopic ranges are present between the massive appinites (ɛNd = +0.39) and different types of mafic-ultramafic rocks in layered outcrops (ɛNd = +1.12 to +2.07) of the complex. Based on the geochemical and isotopic (ratios of Sr, Nd, and Pb) data, we suggest that variations in of contribution of slab-derived fluids or crustal components in the primary melt caused the generation of massive appinites and different types of layered gabbros.

In Situ Determination of Thermoelastic Properties of Magnesite at High Pressure and Temperature With Implications to Seismic Detectability of Moderately Carbonated Lithologies in the Earth's Mantle

AbstractSubduction of carbonate‐bearing oceanic plates into Earth's interior recycles carbon from the surface to the deep mantle. The subducted carbonates can significantly affect mantle properties and dynamics. Magnesite is recognized as one of the major potential carbon hosts in the deep mantle because of its stability up to deep lower mantle conditions. However, despite many previous studies on the equation of state and elastic properties of magnesite, large discrepancies still exist for its elastic moduli and their pressure and temperature derivatives. Here we report in situ density and elastic wave velocity measurements on a natural magnesite at simultaneous high pressure‐temperature conditions up to ∼8 GPa–1073 K in a multi‐anvil apparatus using ultrasonic and synchrotron X‐ray techniques. Global fitting of the data set to finite strain equations yields KS0 = 114.0 ± 1.2 GPa, = 4.9 ± 0.3, = (−0.019 ± 0.002) GPa/K, G0 = 68.6 ± 0.4 GPa, G′ = 1.6 ± 0.1, and = (−0.018 ± 0.001) GPa/K. Compared to other major upper mantle and transition zone minerals, magnesite has intermediate VP, the lowest VS, and the lowest density. Thus, magnesite possesses higher VP/VS ratio than other mantle minerals in normal mantle regions, whereas this feature is less pronounced in subduction zone environments. Modeling of the velocity profiles of carbonated lithologies along different geotherms suggests that moderately‐enriched magnesite domains are unlikely to be detected seismically in the Earth's mantle.

Role of germinal center and CD39highCD73+ B cells in the age-related tonsillar involution

BackgroundThe tonsils operate as a protection ring of mucosa at the gates of the upper aero-digestive tract. They show similarities with lymph nodes and participate as inductive organs of systemic and mucosal immunity. Based on the reduction of their size since puberty, they are thought to experience involution in adulthood. In this context, we have used tonsillar mononuclear cells (TMC) isolated from patients at different stages of life, to study the effect of ageing and the concomitant persistent inflammation on these immune cells.ResultsWe found an age-dependent reduction in the proportion of germinal center B cell population (BGC) and its T cell counterpart (T follicular helper germinal center cells, TfhGC). Also, we demonstrated an increment in the percentage of local memory B cells and mantle zone T follicular helper cells (mTfh). Furthermore, younger tonsils rendered higher proportion of proliferative immune cells within the freshly isolated TMC fraction than those from older ones. We demonstrated the accumulation of a B cell subset (CD20+CD39highCD73+ cells) metabolically adapted to catabolize adenosine triphosphate (ATP) as patients get older. To finish, tonsillar B cells from patients at different ages did not show differences in their proliferative response to stimulation ex vivo, in bulk TMC cultures.ConclusionsThis paper sheds light on the changing aspects of the immune cellular landscape, over the course of time and constant exposure, at the entrance of the respiratory and digestive systems. Our findings support the notion that there is a re-modelling of the immune functionality of the excised tonsils over time. They are indicative of a transition from an effector type of immune response, typically oriented to reduce pathogen burden early in life, to the development of an immunosuppressive microenvironment at later stages, when tissue damage control gets critical provided the time passed under immune attack. Noteworthy, when isolated from such histologic microenvironment, older tonsillar B cells seem to level their proliferation capacity with the younger ones. Understanding these features will not only contribute to comprehend the differences in susceptibility to pathogens among children and adults but would also impact on vaccine developments intended to target these relevant mucosal sites.

Histopathological staging and differential diagnosis of marginal zone lymphoma of gastric mucosa-associated lymphoid tissue

The purpose of this study was to explore the histopathological staging and differential diagnosis of marginal zone lymphoma in gastric mucosa-associated lymphoid tissue (MALT lymphoma). We performed detailed histomorphology and immunohistochemistry investigations as well as genetic testing on endoscopic biopsy and endoscopic mucosal resection specimens from 18 patients with gastric MALT lymphoma. We found that gastric MALT lymphoma typically begins as a small, isolated area outside the lymphoid follicular mantle zone or proliferates in a multifocal, patchy manner, gradually spreads to the interfollicular zone, forming diffuse proliferation, invades the gastric mucosal glands, and infiltrates or proliferates into the center of peripheral reactive lymphoid follicles. Abnormally proliferating lymphocytes invade the surrounding lymphoid follicles, resulting in damage, atrophy, and disappearance of their normal follicles as well as of the gastric mucosa glands, forming diffuse proliferation. Redifferentiation and proliferation lead to the transformation of lymphocytes; that is, MALT transitions into highly invasive lymphoma. Based on our findings in this study, we propose the following five stages in the process of development and progression of gastric MALT lymphoma: the stage of cell proliferation outside the lymphoid follicular mantle zone; the stage of heterogeneous proliferative lymphoepithelial lesion; the stage of reactive lymphoid follicular implantation; the stage of lymphoid follicular clonal proliferation; and the stage of MALT transforming into highly invasive lymphoma. We examined the differential diagnosis of histopathological features at each stage. The clinicopathological staging of gastric MALT lymphoma can help clinicians provide accurate treatment and track malignant cell transformation, thus playing a significant role in controlling its development and progression.

The effect of triterpene glycoside on survival and changes in the cytokine profile in the spleen of BALB/c mice under conditions of lethal influenza infection A/WSN/1/33(H1N1)

BACKGROUND: Currently, the search and development of compounds, including herbal ones, with anti-influenza activity are relevant.
 AIM: To study the effect of oral administration of the triterpene glycoside saponin tauroside Sx1 on survival and changes in the cytokine profile of the spleen of mice under conditions of lethal influenza infection.
 MATERIAL AND METHODS: 78 male BALB/c mice aged 4–6 weeks, weighing 16–18 g, were used. They were divided into groups: first — control group; the second was a group of animals infected with influenza virus A/WSN/1/33(H1N1); the third was a group of infected animals that received saponin tauroside Sx1, isolated from the Crimean ivy Hedera taurica (Hibberd) Carrière at a dose of 11.8 mg/kg per day against the background of a viral infection for 3 days. The survival and expression of interleukins-1β and -10 in the spleen of mice on the 4th and 14th days of the experiment were studied. Spleen fragments were stained with hematoxylin and eosin. Microscopic analysis was performed using a video microscopy system. Immunohistochemical study was performed according to a standard protocol. Intergroup differences were assessed using the Kruskal–Wallis test and the Mann–Whitney U test using MS Office (Excel 2010) and Statistica 10.0.
 RESULTS: Administration of saponin tauroside Sx1 significantly increased the average life expectancy of animals by 4.6 days compared to the group without correction; survival rate was 30.0% (p=0.0233). Against the background of influenza infection, an increase in the number of cells secreting interleukin-1β was detected in the spleen of mice. In the mantle zone of the second group, the level of cytokine expression exceeded the control values by 3.41 times (p=0.0001), and the values of the third group — by 3.38 times (p=0.0001). By the 14th day of the experiment in the mantle zone, expression in the group with saponin administration increased, exceeding the indicators of the group without correction by 34.78% (p=0.0482). By the 4th day of the experiment, in both experimental groups, the number of cells positive for interleukin-10 increased in the mantle zone and decreased compensatoryly in the marginal zone. By the 14th day, in the group without correction, a decrease in expression by 24.86% (p=0.0487) was recorded; after the administration of saponin, the number of immunopositive cells was practically no different from the control (p=0.0443).
 CONCLUSION: Therapeutic administration of saponin tauroside Sx1 stabilizes the cytokine profile of the spleen of mice and promotes their better survival in conditions of lethal influenza infection.

Spleen white pulp structural and cellular composition in experimental furosemide-­induced hypomagnesemia

Relevance. Magnesium deficiency in the blood (hypomagnesemia) is due to many reasons, among which loop diuretics (furosemide) occupy acertain place. The role of the spleen in this process has not been determined. The aim of the work was to elucidate the effect of furosemide-­induced hypomagnesemia on the immune structures of the white pulp of rat spleen. Materials and Methods. Furosemide (Lasix® Aventis Pharma Ltd, India) was injected daily intraperitoneally at adose of 30 mg/kg to the experimental group of white outbred rats for 6 days, animals of the control group received an injection of 0.9% NaCl. Investigated: blood serum for the content of magnesium, calcium, sodium and iron; serial sections of the white pulp of the spleen after staining with hematoxylin and eosin to assess the structure and azure-­II-eosin to assess the cellular composition. With amicroscope magnification of 280 times, the ratio (in%) of primary (PLNS) and secondary lymphoid nodules of the spleen (SLNS) was calculated, the following were measured (µm): the diameter of the germinal center (GC), the width of the mantle and marginal zone, the diameter of the periarteriolar lymphoid sheath (PALS). In GC, the peripheral zone of lymphoid nodules, PALS at amagnification of 1500 times per field of view (100 μm2) was counted and presented as apercentage of the number of lymphocytes; macrophages; cells, mitotic and apoptotic elements. Morphometric analysis was carried out using Image ProPlus6.0 software (Media Cybernetics, USA). Statistical processing was carried out using the Statistica 10.0 software package with the determination of the arithmetic mean (M) and its error (m). Results and Discussion. The administration of furosemide led to adecrease in magnesium in the blood serum by 1.6 times (p0.05). In the white pulp of the spleen of animals of the experimental group, the proportion of SLNS decreased by 18.14%, the number of SLNS increased by 42.5% (p0.05). The diameter of SLNS increased insignificantly, the diameter of GC and the width of the marginal zone significantly increased by 27.1 and 24.8%, respectively. The proportion of macrophages increased by 20.6% in GC SLNS, and by 17.0% in PALS. The highest increase in the proportion of cells with signs of apoptosis was found in the periarteriolar lymphoid sheath of experimental animals - 34.6% (p0.05). Conclusion. Furosemide loading causes the development of dyselementosis, with the most significant loss of magnesium (hypomagnesemia) and has apronounced effect on the immune parameters of the spleen, represented by white pulp structures. Therefore, correction of the elemental status and monitoring of the state of the spleen in hypomagnesemia caused by the use of loop diuretics is anecessary element in the prevention of complications associated with the use of diuretic drugs.

Crystallization of a hydrous magma ocean in the shallow lower mantle

The solidification of a deep magma ocean occurred early in Earth's history. Although the initial amount of H2O in Earth's magma ocean is predicted to be low (e.g., <3000 ppm), as an incompatible element it becomes highly enriched (e.g. >10 wt%) in the final few percent of crystallization. In order to understand how a hydrous magma ocean would crystallize at the top of the lower mantle, we determined liquidus phase relations in the MgO-FeO-CaO-Al2O3-SiO2-H2O system at 24 GPa. We find that the bridgmanite (brg) + stishovite (st) + melt and bridgmanite (brg) + ferropericlase (fp) + melt cotectic boundary curves trend to Mg-rich melt compositions with decreasing temperature and extend to very high H2O contents (∼80 mol% H2O). The brg+st+melt curve is a subtraction curve at < ∼18 mol% H2O and a reaction curve at higher H2O contents, whereas the brg+fp+melt is a subtraction curve throughout its length. The density of melts along the two cotectics leads to neutral buoyancy with respect to shallow lower mantle and transition zone minerals at H2O contents up to ∼25 mol%. A transient melt-rich layer can form at the top of the lower mantle during late-stage crystallization in a mushy magma ocean when melt percolation dominates. When crystallization exceeds ∼98%, hydrous melts (>25 mol% H2O) become buoyant and can percolate into and hydrate the mantle transition zone.

Transcrustal magmatic processes of the Tianshuigou dolerite sill from the ca. 1.32 Ga Yanliao large igneous province: Insights from zoned plagioclase macrocrysts

Transcrustal magmatic processes within the magmatic plumbing systems of large igneous provinces (LIPs) remain poorly constrained. Here we present petrographic textures, whole-rock and mineral geochemistry, and in situ Sr isotopes of several types of zoned plagioclase macrocrysts identified as antecrysts in the shallowly emplaced Tianshuigou dolerite sill from the Yanliao LIP. The goal is to reveal the transcrustal magmatic processes from middle to shallow crust. Our results characterize three zones in the plagioclase macrocrysts: core, mantle, and rim, and we determine that these zones crystallized in different parts of the LIP plumbing system under distinct P-T conditions. The cores of plagioclase macrocrysts originated from a mid-crustal (ca. 17.4 km deep) magma reservoir consisting of crystal mush. The mantle zone of plagioclase macrocrysts records the magma ascent and/or convection processes in a shallower chamber at a depth of ca. 6 km. The rim and groundmass plagioclase crystallized initially in a shallower chamber at a depth of ca. 6 km, and further crystallization of the rim and groundmass occurred during final ascent of the crystal-bearing magma and intrusion into the Xiamaling Formation as dolerite sills. Geothermometers show that the core crystallized at ∼1214 ± 36 °C, the mantle crystallized at ∼1169 ± 36 °C, and the rim and groundmass plagioclase crystallized over a range from ∼1154 ± 36 to 1108 ± 14 °C. The hygrometer data suggest the magma plumbing system is relatively dry (H2O contents <1 wt%). The plagioclase macrocrysts generally show normal zonation from core to rim reflecting overall evolution of magma composition in the plumbing system. Geochemical data suggest that magmas were contaminated by the mafic lower crust prior to crystallization of the plagioclase macrocryst cores in the middle crustal magma reservoir, but that little or no contamination occurred during the magma storage and the ascent in the middle-upper crust. Our results suggest that the zoned plagioclase macrocrysts in mafic sill swarms may record the magmatic processes from the middle to the shallow crust in LIP plumbing systems. The processes that occurred in magma plumbing systems in middle crust play a vital role in the compositions of shallowly emplaced intrusions in LIPs.