Cone beam computed tomography assessment of the prevalence and association of pulp calcification with periodontitis.

Periodontitis has a known association with pathological calcification in the cardiovascular system. Considering the close anatomic and circulatory association between dental pulp and the periodontium, this study aimed to evaluate the prevalence of pulp calcification (PC) under different periodontal conditions, as well as the associations of PC with the degree of periodontal damage, via cone beam computed tomography (CBCT) examination. In this study, 55 patients were categorized into three groups according to periodontal condition: group 1 (healthy controls), group 2 (periodontitis stage I-II), and group 3 (periodontitis stage III-IV). PC and radiographic bone loss (RBL) was assessed by CBCT in sagittal, axial, and coronal views, and statistical analyses were conducted. PC was identified in 378 of 1170 teeth (32.3%). The prevalence significantly differed among the three groups (P < 0.001). Group 2 had a 2.43-fold (P < 0.001, 95% confidence interval [CI] 1.64-3.61) higher risk of PC than group 1; and the risk of PC was 3.04-fold (P < 0.001, 95% CI 2.06-4.48) higher in group 3 than group 1. Teeth with more severe RBL exhibited a higher prevalence of PC (P < 0.001). Molar teeth had a higher risk of PC than incisors and premolars. In conclusion, the occurrence of PC is related to the periodontal state, and the prevalence of PC is higher in teeth with periodontitis; tooth type and periodontitis status are important risk factors for PC.

Oral supplementation of inorganic pyrophosphate in pseudoxanthoma elasticum.

Pseudoxanthoma elasticum (PXE; OMIM 264800) is a rare heritable multisystem disorder, characterized by ectopic mineralization affecting elastic fibres in the skin, eyes and the cardiovascular system. Skin findings often lead to early diagnosis of PXE, but currently, no specific treatment exists to counteract the progression of symptoms. PXE belongs to a group of Mendelian calcification disorders linked to pyrophosphate metabolism, which also includes generalized arterial calcification of infancy (GACI) and arterial calcification due to CD73 deficiency (ACDC). Inactivating mutations in ABCC6, ENPP1 and NT5E are the genetic cause of these diseases, respectively, and all of them result in reduced inorganic pyrophosphate (PPi ) concentration in the circulation. Although PPi is a strong inhibitor of ectopic calcification, oral supplementation therapy was initially not considered because of its low bioavailability. Our earlier work however demonstrated that orally administered pyrophosphate inhibits ectopic calcification in the animal models of PXE and GACI, and that orally given Na4 P2 O7 is absorbed in humans. Here, we report that gelatin-encapsulated Na2 H2 P2 O7  has similar absorption properties in healthy volunteers and people affected by PXE. The sodium-free K2 H2 P2 O7 form resulted in similar uptake in healthy volunteers and inhibited calcification in Abcc6-/- mice as effectively as its sodium counterpart. Novel pyrophosphate compounds showing higher bioavailability in mice were also identified. Our results provide an important step towards testing oral PPi in clinical trials in PXE, or potentially any condition accompanied by ectopic calcification including diabetes, chronic kidney disease or ageing.

Role of NGF-TrkA signaling in calcification of articular chondrocytes.

Nerve growth factor (NGF) is a key regulator of chronic osteoarthritic pain, but the exact targets of NGF action on human articular cartilage is unknown. This study aimed to test the hypothesis that the NGF-tropomyosin receptor kinase A (TrkA) (high-affinity NGF receptor) pathway plays a role in the calcification process of human articular chondrocytes (hACs). A 14-aa small peptide of NGF (Nsp) previously shown to activate NGF signaling in rat PC12 cells was used as an NGF signaling agonist, and recombinant NGF and the pan-Trk inhibitor GNF-5837 were employed as signaling modulating agents. The functional consequences of NGF-TrkA signaling were examined in human healthy articular chondrocytes maintained under conditions supportive of osteogenesis in vitro. The NGF-mimetic bioactivity of Nsp was first confirmed on the basis of maintenance of neurite outgrowth in PC12 cells. Primary human chondrocytes responded to Nsp in vitro. Perturbation of NGF signaling with NGF, Nsp, and GNF-5837 resulted in a strong induction of chondrocyte calcification, and gene expression data suggested that the Indian Hedgehog-parathyroid hormone-related protein signaling axis was involved. These findings suggest functional involvement of NGF signaling in calcification of hACs and the importance of NGF signaling in articular cartilage homeostasis.-Jiang, Y., Tuan, R. S. Role of NGF-TrkA signaling in calcification of articular chondrocytes.

Recent Advances on Relationship Between Inorganic Phosphate and Pathologic Calcification: Is Calcification After Breast Augmentation with Fat Grafting Correlated with Locally Increased Concentration of Inorganic Phosphate?

BACKGROUND: Pathologic calcification has frequently occurred after breast augmentation with fat grafting as well as other conditions such as breast cancer, trauma, myocardial infarction, arteriosclerosis and even after reduction mammoplasty. Inorganic phosphate, correlated with fat metabolism, is an important factor that induces pathologic calcification such as vascular calcification. METHODS: A literature search was conducted using PubMed with the keywords: calcification, inorganic phosphate, fat. Studies related to the process of pathologic calcification, correlation between inorganic phosphate and pathologic calcification, between inorganic phosphate and fat metabolism in pathologic calcification were collected. RESULTS: Various mechanisms were referred to in pathologic calcification among which inorganic phosphate played an important role. Inorganic phosphate could be liberated, under the effect of various enzymes, in the process of fat metabolism. The authors hypothesized that a large-scale necrotizing zone, which could occur in fat grafting with large amounts per cannula, might provide a high-phosphate environment which might contribute to differentiation of surrounding cells such as stem cells or regenerated vessel cells into osteoblast-like cells that induce pathologic calcification. CONCLUSION: Inorganic phosphate, which was correlated with fat metabolism, played a significant role in pathologic calcification. We firstly hypothesize that calcification after fat grafting may be related to locally increasing concentrations of phosphate in a necrotizing zone. Further research should be conducted to verify this hypothesis. LEVEL OF EVIDENCE V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Vitamin K as a Powerful Micronutrient in Aging and Age-Related Diseases: Pros and Cons from Clinical Studies.

Vitamin K is a multifunctional micronutrient implicated in age-related diseases such as cardiovascular diseases, osteoarthritis and osteoporosis. Although vitamin K-dependent proteins (VKDPs) are described to have a crucial role in the pathogenesis of these diseases, novel roles have emerged for vitamin K, independently of its role in VKDPs carboxylation. Vitamin K has been shown to act as an anti-inflammatory by suppressing nuclear factor κB (NF-κB) signal transduction and to exert a protective effect against oxidative stress by blocking the generation of reactive oxygen species. Available clinical evidences indicate that a high vitamin K status can exert a protective role in the inflammatory and mineralization processes associated with the onset and progression of age-related diseases. Also, vitamin K involvement as a protective super-micronutrient in aging and 'inflammaging' is arising, highlighting its future use in clinical practice. In this review we summarize current knowledge regarding clinical data on vitamin K in skeletal and cardiovascular health, and discuss the potential of vitamin K supplementation as a health benefit. We describe the clinical evidence and explore molecular aspects of vitamin K protective role in aging and age-related diseases, and its involvement as a modulator in the interplay between pathological calcification and inflammation processes.

Exploring the Link Between Autophagy-Lysosomal Dysfunction and Early Heterotopic Ossification in Tendons.

Heterotopic ossification (HO), the pathological formation of bone within soft tissues such as tendon and muscle, is a notable complication resulting from severe injury. While soft tissue injury is necessary for HO development, the specific molecular pathology responsible for trauma-induced HO remains a mystery. The previous study detected abnormal autophagy function in the early stages of tendon HO. Nevertheless, it remains to be determined whether autophagy governs the process of HO generation. Here, trauma-induced tendon HO model is used to investigate the relationship between autophagy and tendon calcification. In the early stages of tenotomy, it is observed that autophagic flux is significantly impaired and that blocking autophagic flux promoted the development of more rampant calcification. Moreover, Gt(ROSA)26sor transgenic mouse model experiments disclosed lysosomal acid dysfunction as chief reason behind impaired autophagic flux. Stimulating V-ATPase activity reinstated both lysosomal acid functioning and autophagic flux, thereby reversing tendon HO. This present study demonstrates that autophagy-lysosomal dysfunction triggers HO in the stages of tendon injury, with potential therapeutic targeting implications for HO.

Lysosomal destabilization: A missing link between pathological calcification and osteoarthritis.

Calcification of cartilage by hydroxyapatite is a hallmark of osteoarthritis and its deposition strongly correlates with the severity of osteoarthritis. However, no effective strategies are available to date on the prevention of hydroxyapatite deposition within the osteoarthritic cartilage and its role in the pathogenesis of this degenerative condition is still controversial. Therefore, the present work aims at uncovering the pathogenic mechanism of intra-cartilaginous hydroxyapatite in osteoarthritis and developing feasible strategies to counter its detrimental effects. With the use of in vitro and in vivo models of osteoarthritis, hydroxyapatite crystallites deposited in the cartilage are found to be phagocytized by resident chondrocytes and processed by the lysosomes of those cells. This results in lysosomal membrane permeabilization (LMP) and release of cathepsin B (CTSB) into the cytosol. The cytosolic CTSB, in turn, activates NOD-like receptor protein-3 (NLRP3) inflammasomes and subsequently instigates chondrocyte pyroptosis. Inhibition of LMP and CTSB in vivo are effective in managing the progression of osteoarthritis. The present work provides a conceptual therapeutic solution for the prevention of osteoarthritis via alleviation of lysosomal destabilization.

Ex vivo model of pathological calcification of human aortic valve.

The development of drug therapy for the pathological calcification of the aortic valve is still an open issue due to the lack of effective treatment strategies. Currently, the only option for treating this condition is surgical correction and symptom management. The search for models to study the safety and efficacy of anti-calcifying drugs requires them to not only be as close as possible to in vivo conditions, but also to be flexible with regard to the molecular studies that can be applied to them. The ex vivo model has several advantages, including the ability to study the effect of a drug on human cells while preserving the original structure of the valve. This allows for a better understanding of how different cell types interact within the valve, including non-dividing cells. The aim of this study was to develop a reproducible ex vivo calcification model based on valves from patients with calcific aortic stenosis. We aimed to induce spontaneous calcification in valve tissue fragments under osteogenic conditions, and to demonstrate the possibility of significantly suppressing it using a calcification inhibitor. To validate the model, we tested a Notch inhibitor Crenigacestat (LY3039478), which has been previously shown to have an anti-calcifying effect on interstitial cell of the aortic valve. We demonstrate here an approach to testing calcification inhibitors using an ex vivo model of cultured human aortic valve tissue fragments. Thus, we propose that ex vivo models may warrant further investigation for their utility in studying aortic valve disease and performing pre-clinical assessment of drug efficacy.

Pathological calcification in osteoarthritis: an outcome or a disease initiator?

In the progression of osteoarthritis, pathological calcification in the affected joint is an important feature. The role of these crystallites in the pathogenesis and progression of osteoarthritis is controversial; it remains unclear whether they act as a disease initiator or are present as a result of joint damage. Recent studies reported that the molecular mechanisms regulating physiological calcification of skeletal tissues are similar to those regulating pathological or ectopic calcification of soft tissues. Pathological calcification takes place when the equilibrium is disrupted. Calcium phosphate crystallites are identified in most affected joints and the presence of these crystallites is closely correlated with the extent of joint destruction. These observations suggest that pathological calcification is most likely to be a disease initiator instead of an outcome of osteoarthritis progression. Inhibiting pathological crystallite deposition within joint tissues therefore represents a potential therapeutic target in the management of osteoarthritis.

Vitamin K as a Diet Supplement with Impact in Human Health: Current Evidence in Age-Related Diseases.

Vitamin K health benefits have been recently widely shown to extend beyond blood homeostasis and implicated in chronic low-grade inflammatory diseases such as cardiovascular disease, osteoarthritis, dementia, cognitive impairment, mobility disability, and frailty. Novel and more efficient nutritional and therapeutic options are urgently needed to lower the burden and the associated health care costs of these age-related diseases. Naturally occurring vitamin K comprise the phylloquinone (vitamin K1), and a series of menaquinones broadly designated as vitamin K2 that differ in source, absorption rates, tissue distribution, bioavailability, and target activity. Although vitamin K1 and K2 sources are mainly dietary, consumer preference for diet supplements is growing, especially when derived from marine resources. The aim of this review is to update the reader regarding the specific contribution and effect of each K1 and K2 vitamers in human health, identify potential methods for its sustainable and cost-efficient production, and novel natural sources of vitamin K and formulations to improve absorption and bioavailability. This new information will contribute to foster the use of vitamin K as a health-promoting supplement, which meets the increasing consumer demand. Simultaneously, relevant information on the clinical context and direct health consequences of vitamin K deficiency focusing in aging and age-related diseases will be discussed.

The role of extracellular vesicles in biomineralisation: current perspective and application in regenerative medicine.

Extracellular vesicles comprise a heterogenous population of exosomes and microvesicles that have critical roles in intercellular signalling and tissue development. These complex particles have been implicated as mediators of the therapeutic effects of stem cells via the transfer of an assorted cargo of proteins and nucleic acids, which can modulate inflammation and enhance endogenous regeneration in a range of tissues. In addition, extracellular vesicles have the capacity to be loaded with therapeutic molecules for targeted delivery of pharmaceuticals. The versatility, biostability and biocompatibility of extracellular vesicles make them appealing for regenerative medicine and may endow considerable advantages over single molecule approaches. Furthermore, since production can be optimised and assessed ex vivo, extracellular vesicles present a decreased risk of neoplastic transformation when compared with cell-based methods. To date, the contribution of vesicles to tissue development has perhaps been most comprehensively defined within hard tissues, such as endochondral bone, where they were first identified in 1969 and henceforth referred to as matrix vesicles. Within developing bone, vesicles function as vehicles for the delivery of pro-osteogenic factors and initiate early nucleational events necessary for matrix mineralisation. However, advancement in our understanding of the biogenesis and characterisation of matrix vesicles has occurred largely in parallel to associated developments in wider extracellular vesicle biology. As such, there is a requirement to align current understanding of matrix vesicle-mediated mineralisation within the context of an evolving literature surrounding exosomes and microvesicles. In this review, we present an overview of current progress and opinion surrounding the application of vesicles in regenerative medicine with a primary focus on their potential as an acellular approach for enhancing hard tissue regeneration. This is balanced with an assessment of areas where further development is required to maximise their application for regenerative medicine.

Metastatic calcification of floor of the mouth secondary to chronic renal failure-report of a rare case with atypical presentation.

Soft-tissue calcification is always pathological. Metastatic calcification is calcification of soft tissues owing to hyperphosphataemia with or without hypercalcaemia. Metastatic calcification of oral cavity is extremely rare. A case report of metastatic calcification of the floor of the mouth with atypical radiologic and clinical picture is presented here along with a review of earlier reports. A chance finding of the granular oral mucosa on palpation led to a radiographic examination revealing granular calcifications of the floor of the mouth. Blood chemistry and hormone analysis revealed chronic renal failure and hyperparathyroidism. A diagnosis of metastatic calcification secondary to renal failure was made and the treatment was aimed at correcting the renal failure without any intervention for the asymptomatic calcifications. Key differences between the present case and other cases reported in the literature are outlined.

Nódulo doloroso en glúteo. A propósito de un caso / Painful nodule in the buttock. About a case...

Se presenta el caso clínico de un paciente con calcinosis cutis distrófica en glúteo, una pa- tología infrecuente e infra-diagnosticada por la falta de sospecha clínica. Es de vital importancia que a quienes presenten calcificaciones cutáneas se les realice una detallada anamnesis y un estudio analítico con función renal, metabolismo del calcio y fósforo y autoinmunidad para descartar la existencia de una patología subyacente como las enfermedades autoinmunes o renales..(AU)

We present the clinical case of a patient with calcinosis dystrophic skin on the buttock, an infre- quent and infradiagnosed pathology due to the lack of clinical suspicion. It is very important that those patients with skin calcifications have a detalied anamnesis and analytical study with renal function, calcium and phosphrus metabolism and autoinmmunity to rule out the existence of un- derlying pathology such an autoimmune or renal diseases..(AU)

Structure of the calcium pyrophosphate monohydrate phase (Ca2P2O7·H2O): towards understanding the dehydration process in calcium pyrophosphate hydrates.

Calcium pyrophosphate hydrate (CPP, Ca(2)P(2)O(7) · nH2O) and calcium orthophosphate compounds (including apatite, octacalcium phosphate etc.) are among the most prevalent pathological calcifications in joints. Even though only two dihydrated forms of CPP (CPPD) have been detected in vivo (monoclinic and triclinic CPPD), investigations of other hydrated forms such as tetrahydrated or amorphous CPP are relevant to a further understanding of the physicochemistry of those phases of biological interest. The synthesis of single crystals of calcium pyrophosphate monohydrate (CPPM; Ca(2)P(2)O(7) · H2O) by diffusion in silica gel at ambient temperature and the structural analysis of this phase are reported in this paper. Complementarily, data from synchrotron X-ray diffraction on a CPPM powder sample have been fitted to the crystal parameters. Finally, the relationship between the resolved structure for the CPPM phase and the structure of the tetrahydrated calcium pyrophosphate ß phase (CPPT-ß) is discussed.

Vejiga de porcelana como consecuencia de esquistosomiasis urinaria. Presentación de un caso clínico con enfoque multidisciplinario

La esquistosomiasis urogenital es una de las muchas parasitosis que padecen los habitantes de los países con poco nivel de desarrollo. Esta enfermedad, como algunas otras parasitosis, está aumentando su incidencia en algunos países como consecuencia de una mayor movilidad poblacional. Se presenta el caso de una paciente de 35 años que fue internada en la sala de medicina de mujeres del Hospital General de Malange con presencia de dolor en hipogastrio, escalofríos y hematuria final intermitente que padecía desde hacía 2 meses. Después de realizar algunos exámenes complementarios, se comprobó presencia de huevos de Shistosomas en muestra de orina y calcificación de la vejiga en forma de porcelana observada en radiografía simple de abdomen. Con el diagnóstico de Shistosomiasis urinaria, recibió tratamiento con praziquantel a 40 mg por kg. de peso en dosis única. La paciente egresó una semana después y fue seguida de forma ambulatoria. Actualmente se encuentra recuperada e incorporada a sus actividades habituales.

Uro-genital schistosomiasis is one of the parasite infections suffered by inhabitants of underdeveloped countries. This disease, as some other parasite infections, is increasing its incidence in some other as a consequence of higher population mobility. A case of a 35 year old woman is presented who was admitted to Malange General Hospital complaining of hypo-gastric pain, chills and final intermittent hematuria she had had for two monhs. After some lab tests, it was confirmed the presence of Schistosomas eggs in a urine sample and calcification of the bladder in porcelain form observed in a simple abdominal radiography. With the diagnosis of urinary schistosomiasis, she was treated with praziquantel at 40 mg per kg in a single dose. The patient came back a week later and afterwards for follow up. She is currently cured and doing her routines.