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1.
Osteoporos Int ; 35(5): 919-927, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38507080

RESUMEN

Sheehan's syndrome (SS) is a rare but well-characterized cause of hypopituitarism. Data on skeletal health is limited and on microarchitecture is lacking in SS patients. PURPOSE: We aimed to explore skeletal health in SS with bone mineral density (BMD), turnover, and microarchitecture. METHODS: Thirty-five patients with SS on stable replacement therapy for respective hormone deficiencies and 35 age- and BMI-matched controls were recruited. Hormonal profile and bone turnover markers (BTMs) were measured using electrochemiluminescence assay. Areal BMD and trabecular bone score were evaluated using DXA. Bone microarchitecture was assessed using a second-generation high-resolution peripheral quantitative computed tomography. RESULTS: The mean age of the patients was 45.5 ± 9.3 years with a lag of 8.3 ± 7.2 years prior to diagnosis. Patients were on glucocorticoid (94%), levothyroxine (94%), and estrogen-progestin replacement (58%). None had received prior growth hormone (GH) replacement. BTMs (P1NP and CTX) were not significantly different between patients and controls. Osteoporosis (26% vs. 16%, p = 0.01) and osteopenia (52% vs. 39%, p = 0.007) at the lumbar spine and femoral neck (osteoporosis, 23% vs. 10%, p = 0.001; osteopenia, 58% vs. 29%, p = 0.001) were present in greater proportion in SS patients than matched controls. Bone microarchitecture analysis revealed significantly lower cortical volumetric BMD (vBMD) (p = 0.02) at the tibia, with relative preservation of the other parameters. CONCLUSION: Low areal BMD (aBMD) is highly prevalent in SS as compared to age- and BMI-matched controls. However, there were no significant differences in bone microarchitectural measurements, except for tibial cortical vBMD, which was lower in adequately treated SS patients.


Asunto(s)
Enfermedades Óseas Metabólicas , Hipopituitarismo , Osteoporosis , Femenino , Humanos , Adulto , Persona de Mediana Edad , Densidad Ósea , Osteoporosis/diagnóstico por imagen , Hipopituitarismo/diagnóstico por imagen , Hipopituitarismo/tratamiento farmacológico , Tomografía Computarizada por Rayos X , Tibia/diagnóstico por imagen , Radio (Anatomía) , Absorciometría de Fotón/métodos
2.
Calcif Tissue Int ; 104(5): 561-569, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31069441

RESUMEN

Fibrogenesis imperfecta ossium (FIO) is an extremely uncommon fatal bone disorder of poorly understood etiology. The pathogenesis of FIO is not well known. The fundamental skeletal defect appears to be an abnormality in organic matrix of bone characterized by defective mineralization of the abnormal collagen. FIO clinically manifests in middle-aged adults presenting with fracture and bone pain. Elevated serum alkaline phosphatase is the only and the most consistent biochemical abnormality. Although paraproteinemia is observed in one-third of cases, the pathogenic link to the disease process is unclear. Limited information on FIO and its close resemblance to many metabolic bone disorders leads to delayed or missed diagnoses and management. Prednisolone, bisphosphonates, melphalan and steroids have been tried previously with variable success. Recently, a trial of recombinant growth hormone therapy was found to be effective. Further research focused on the pathogenetic mechanisms of FIO is needed to identify and develop targeted therapeutic options.


Asunto(s)
Enfermedades Óseas Metabólicas/diagnóstico , Colágeno/metabolismo , Osteogénesis Imperfecta/diagnóstico , Fosfatasa Alcalina/sangre , Biopsia , Enfermedades Óseas Metabólicas/complicaciones , Enfermedades Óseas Metabólicas/terapia , Huesos/patología , Difosfonatos/uso terapéutico , Progresión de la Enfermedad , Fracturas Óseas/etiología , Humanos , Melfalán/uso terapéutico , Mutación , Osteogénesis Imperfecta/complicaciones , Osteogénesis Imperfecta/terapia , Paraproteinemias/sangre , Prednisolona/uso terapéutico , Pronóstico , Cintigrafía , Esteroides/uso terapéutico
3.
Calcif Tissue Int ; 94(2): 240-7, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24154985

RESUMEN

Camurati-Engelmann disease (CED, OMIM 131300), or progressive diaphyseal dysplasia, is a rare autosomal dominant skeletal dysplasia, caused by mutations in the transforming growth factor-ß1 (TGFß1) gene. We describe the first Indian CED family with genetic confirmation and presenting manifestations. The proband is a 17-year-old woman who presented with lower limb pain and proximal muscle weakness. Skeletal radiographs of the long bones revealed cortical, periosteal, and endosteal thickenings, predominantly affecting the diaphyses of the long bones. On detailed evaluation, there was a strong family history of bone disorder with similar symptoms of pain and radiological findings in several family members. Exon sequencing of the TGFß1 gene was performed in available family members. Based on clinical and radiographic studies and its familial nature, a diagnosis of CED was made and confirmed by mutation analysis. A heterozygous G to A transition in exon 4 of the TGFß1 gene (R218H) was detected in 5 out of 10 available family members, including 4 affecteds and 1 asymptomatic individual. Many of our affected individuals responded to glucocorticoids and cortical windowing. CED is a rare genetic disease with variable clinical manifestations and incomplete penetrance. CED needs to be considered in the differential diagnosis of nonspecific limb pain and waddling gait in all young individuals.


Asunto(s)
Síndrome de Camurati-Engelmann , Adolescente , Pueblo Asiatico , Síndrome de Camurati-Engelmann/diagnóstico por imagen , Femenino , Humanos , Extremidad Inferior , Debilidad Muscular/diagnóstico por imagen , Mialgia/diagnóstico por imagen , Linaje , Radiografía , Cintigrafía , Imagen de Cuerpo Entero
5.
Indian J Med Res ; 140(1): 46-54, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25222777

RESUMEN

BACKGROUND & OBJECTIVES: Bisphosphonates (BPs) are the most widely prescribed medicines for the treatment of osteoporosis because of their efficacy and favourable safety profile. There have been, several reports on an increased incidence of atypical femoral fractures after long term treatment with BPs. The objective of this study was to evaluate the clinical presentation including prodromal symptoms, skeletal radiograph findings, type and duration of BPs received and treatment outcome of patients who developed atypical femoral fractures during bisphosphonate therapy. METHODS: In this retrospective study, eight patients with atypical femoral fractures were analysed based on clinical features, biochemical and radiological investigations. RESULTS: Of the eight patients, who sustained atypical femoral fractures, six were on alendronate and two were on zoledronate therapy before the fractures. In addition to BPs, two patients were on long term corticosteroid therapy for rheumatoid arthritis and Addison's disease. Three patients had bilateral atypical femoral fractures. Except one, all of them had prodromal symptoms prior to fracture. Skeletal radiograph showed cortical thickening, pointed (beaking of) cortical margin and transverse fracture in meta-diaphyseal location. Serum calcium, phosphate, alkaline phosphatase (ALP) and intact parathyroid hormone (iPTH) concentrations were within the reference range in all patients. INTERPRETATION & CONCLUSIONS: Long term bisphosphonate therapy may increase the risk of atypical femoral fractures. Presence of prodromal pain, thickened cortex with cortical beaking may be an early clue for predicting the atypical fractures. High risk patients need periodical skeletal survey and a close follow up for early detection of cases.


Asunto(s)
Difosfonatos/efectos adversos , Difosfonatos/uso terapéutico , Fracturas del Fémur/inducido químicamente , Fracturas del Fémur/diagnóstico por imagen , Osteoporosis/tratamiento farmacológico , Absorciometría de Fotón , Adulto , Anciano , Alendronato , Femenino , Humanos , Imidazoles , India , Persona de Mediana Edad , Osteoporosis/diagnóstico por imagen , Síntomas Prodrómicos , Estudios Retrospectivos , Ácido Zoledrónico
6.
Diabetes Metab Syndr ; 18(8): 103109, 2024 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-39191163

RESUMEN

CONTEXT: Type 2 Diabetes Mellitus (T2D) is associated with an increased risk of fragility fracture despite normal areal bone mineral density (BMD). The contribution of diabetic peripheral neuropathy (PN) to volumetric BMD (vBMD) and bone microarchitecture in T2D is not explored. OBJECTIVE: To assess vBMD and microarchitectural properties of bone using high-resolution peripheral quantitative computed tomography (HR-pQCT) in patients of T2D with or without PN. DESIGN: This is a cross-sectional study of patients of T2D divided into two groups [patients with T2D without PN (Group A) and T2D with PN (Group B)]. All patients underwent clinical examination, biochemical evaluation, dual-energy X-ray absorptiometry (DXA), and HR-pQCT of the radius and tibia. RESULTS: A total of 296 patients were included in the study [Group A (n = 98), Group B (n = 198)]. HR-pQCT demonstrated a significant difference in total vBMD[mg/cm3] at tibia (291.6 ± 61.8 vs. 268.2 ± 63.0; p-0.003); cortical vBMD[mg/cm3] at tibia [912.5 (863.3, 962.4) vs. 853.8 (795.3, 913.2) p-0.000], among groups A and B respectively. Among the microarchitecture parameters, there was a significant difference in cortical porosity at the tibia (2.5% ±1.7% vs. 3%±1.7%; p-0.004), trabecular number[mm-1] at the tibia [1.080 (0.896, 1.237) vs. 1.140 (0.983, 1.286), p-0.045] and trabecular thickness[mm] at the radius [0.228 (0.217, 0.247) Vs. 0.238 (0.224, 0.253); p-0.006], among groups A and B respectively. CONCLUSION: Despite comparable areal BMD, T2D patients with PN have diminished vBMD and deteriorated skeletal microarchitecture, compared to those without PN.

7.
JBMR Plus ; 8(11): ziae117, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39372604

RESUMEN

Thalassemic osteopathy includes low bone mass and impaired bone microarchitecture. We aimed to evaluate the prevalence and determinants of bone quantity (osteoporosis) and quality (microarchitecture) in a cohort of adult patients with transfusion-dependent thalassemia (TDT). Patients with TDT (n = 63) and age- and BMI-matched controls (n = 63) were recruited in the study. Areal bone mineral density (BMD) was measured using DXA Hologic scanner. P1NP and ß-CTX were estimated by electrochemiluminescence assay. Bone geometry and volumetric BMD (vBMD) were estimated by second-generation high-resolution peripheral quantitative computed tomography. Bone turnover marker ß-CTX was significantly lower in the TDT group, but there was no difference in P1NP levels. Low bone mass (Z ≤ -2) was present in greater proportion of patients both at lumbar spine (LS) (54 vs 0%; p = .001) and femoral neck (FN) (33 vs 8%; p = .001). Hypogonadism was associated with low BMD at FN (OR 10.0; 95% CI, 1.2-86; p = .01) and low hemoglobin with low BMD at LS (OR 1.58; 95% CI, 0.96-2.60; p = .07). The mean trabecular bone score was also significantly lower in patients compared with controls (1.261 ± 0.072 vs 1.389 ± 0.058). Total, cortical and trabecular vBMD were significantly lower in cases than controls. The trabecular number and cortical thickness were significantly lower and trabecular separation higher in cases than controls. Adults with TDT have significantly lower areal, cortical and trabecular vBMD. The bone microarchitecture is also significantly impaired in terms of lower number and wider spacing of trabeculae as well as lower cortical thickness and area at both radius and tibia.

8.
J Proteomics ; 302: 105200, 2024 06 30.
Artículo en Inglés | MEDLINE | ID: mdl-38772440

RESUMEN

BACKGROUND AND AIMS: Postmenopausal osteoporosis (PMO) and type 2 diabetes mellitus (T2DM) frequently coexist in postmenopausal women. The study aimed to explore metabolic variations linked to these circumstances and their simultaneous presence through proton nuclear magnetic resonance metabolomics (1H NMR). MATERIALS AND METHODS: Serum samples from 80 postmenopausal women, including 20 PMO individuals, 20 T2DM, 20 T2DM + PMO, and 20 healthy postmenopausal women, were analyzed using 1H NMR spectroscopy. RESULTS: Our study revealed significant metabolic profile differences among the four groups. Notably, the T2DM + PMO group showed elevated levels of alanine, pyruvate, glutamate, lactate, and aspartate, indicating their involvement in lipid metabolism, energy, and amino acids. Importantly, our multivariate statistical analysis identified a metabolite set that accurately distinguished the groups, suggesting its potential as an early diagnostic marker. CONCLUSION: The 1H NMR metabolomics approach uncovered metabolic biomarkers intricately linked to postmenopausal osteoporosis (PMO), type 2 diabetes mellitus (T2DM), and their concurrent presence. Among these biomarkers, alanine emerged as a pivotal player, showing its significant role in the metabolic landscape associated with PMO and T2DM. These findings shed light on the pathophysiological mechanisms underlying these conditions and underscore alanine's potential as a diagnostic biomarker.


Asunto(s)
Biomarcadores , Diabetes Mellitus Tipo 2 , Metabolómica , Osteoporosis Posmenopáusica , Humanos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Femenino , Persona de Mediana Edad , Biomarcadores/sangre , Metabolómica/métodos , Osteoporosis Posmenopáusica/metabolismo , Osteoporosis Posmenopáusica/sangre , Osteoporosis Posmenopáusica/diagnóstico , Anciano , Espectroscopía de Resonancia Magnética/métodos , Metaboloma
9.
Arch Virol ; 158(11): 2359-63, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23685897

RESUMEN

Mumps is a vaccine-preventable disease that usually occurs as a self-limiting parotitis, but it can also lead to several life-threatening complications, including pancreatitis, meningitis, and encephalitis. The molecular epidemiology of the virus is poorly understood. The present study describes an outbreak of mumps virus infection in Punjab, India. The etiology was confirmed by serology and RNA detection to be mumps virus in 72 % of the cases and 50 % of contacts. This study, for the first time, revealed the mumps virus genotypes circulating in the Indian subcontinent as subtype G2 of genotype G.


Asunto(s)
Brotes de Enfermedades , Epidemiología Molecular , Virus de la Parotiditis/genética , Paperas/epidemiología , Paperas/virología , Anticuerpos Antivirales/sangre , Niño , Femenino , Genotipo , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , India/epidemiología , Masculino , Tipificación Molecular , Virus de la Parotiditis/clasificación , Virus de la Parotiditis/inmunología , Virus de la Parotiditis/aislamiento & purificación , Parotiditis/epidemiología , Parotiditis/virología , ARN Viral/sangre , ARN Viral/genética , ARN Viral/aislamiento & purificación
10.
J Biomech ; 161: 111853, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37890220

RESUMEN

In this study, the role of inelastic deformation of bone on its strain rate-dependent mechanical behaviour was investigated. For this, human cortical bone samples were cyclically loaded to accumulate inelastic strain and subsequently, mechanical response was investigated under compressive loading at different strain rates. The strain rate behaviour of fatigued samples was compared with non-loaded control samples. Furthermore, cyclic loading-induced microdamage was quantified through histological analysis. The compression test results show that the strength of fatigue-loaded bone reduced significantly at low strain rates but not at high strain rates. The difference in microcrack density was not significant between fatigued and control groups. The results indicate that the mechanism of load transfer varies between low strain rate and high strain rate regimes. The inelastic deformation mechanisms are more prominent at low strain rates but not at high strain rates. This study shed light on the role of inelastic deformation on the rate-dependent behaviour of cortical bone.


Asunto(s)
Huesos , Hueso Cortical , Humanos , Presión , Fatiga , Estrés Mecánico
11.
Bone ; 173: 116788, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37172883

RESUMEN

Osteopetrosis (OPT) denotes the consequences from failure of osteoclasts to resorb bone and chondroclasts to remove calcified physeal cartilage throughout growth. Resulting impairment of skeletal modeling, remodeling, and growth compromises widening of medullary spaces, formation of the skull, and expansion of cranial foramina. Thus, myelophthisic anemia, raised intracranial pressure, and cranial nerve palsies complicate OPT when severe. Osteopetrotic bones fracture due to misshaping, failure of remodeling to weave the collagenous matrix of cortical osteons and trabeculae, persistence of mineralized growth plate cartilage, "hardening" of hydroxyapatite crystals, and delayed healing of skeletal microcracks. Teeth may fail to erupt. Now it is widely appreciated that OPT is caused by germline loss-of-function mutation(s) usually of genes involved in osteoclast function, but especially rarely of genes necessary for osteoclast formation. Additionally, however, in 2003 we published a case report demonstrating that prolonged excessive dosing during childhood of the antiresorptive aminobisphosphonate pamidronate can sufficiently block osteoclast and chondroclast activity to recapitulate the skeletal features of OPT. Herein, we include further evidence of drug-induced OPT by illustrating osteopetrotic skeletal changes from repeated administration of high doses of the aminobisphosphonate zoledronic acid (zoledronate) given to children with osteogenesis imperfecta.


Asunto(s)
Fracturas Óseas , Osteopetrosis , Niño , Humanos , Osteopetrosis/genética , Osteoclastos , Ácido Zoledrónico , Cráneo
12.
Med Eng Phys ; 104: 103810, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35641076

RESUMEN

Type 2 diabetes (T2D) is a well-known disease that impaired bone mechanical properties and increases the risk of fragility fracture. The bone tissue is a viscoelastic material that means the loading rate determines its mechanical properties. This study investigates the impact of T2D on the viscoelastic properties of human bone and its association with microstructure and biochemical properties. INTRODUCTION: Viscoelasticity is an important mechanical property of bone and for this the interaction of individual constituents of bone plays an important role. The viscoelastic nature of bone can be affected by aging and diseases, which can further influence its deformation and damage behavior. METHODS: The present study investigated the effects of T2D on the viscoelastic behavior of trabecular bone. The femoral heads of T2D (n = 26) and non-T2D (n = 40) individuals with hip fragility fractures were collected for this investigation. Following the micro-CT scanning of all bone samples, the stress relaxation and dynamic mechanical analysis (DMA) tests were performed to quantify the viscoelasticity of bone. Further, a correlation analysis was performed to investigate the effects of alteration in bone microstructural and biochemical parameters on viscoelasticity. RESULTS: The stress relaxation and frequency sweep responses of T2D and non-T2D trabecular bone specimens were not found significantly different. However, the storage modulus, initial stiffness, and initial stress were found lower in T2D bone. The significant correlation of percentage stress relaxed is obtained between the mineral content (r= - 0.52, p-value = 0.003), organic content (r = 0.40, p-value = 0.02), and mineral-to-matrix ratio (r = - 0.43, p-value = 0.009). Further, storage and loss modulus were correlated with bone volume fraction (BV/TV) for both groups. The stress relaxation and frequency sweep characteristics were not found significantly connected with the other chemical, structural, or clinical parameters. CONCLUSION: This study suggests that T2D does not affect the time-dependent response of human femoral trabecular bone. The viscoelastic properties are positively correlated with organic content and negatively correlated with mineral content.


Asunto(s)
Diabetes Mellitus Tipo 2 , Fracturas de Cadera , Hueso Esponjoso/diagnóstico por imagen , Hueso Esponjoso/fisiología , Diabetes Mellitus Tipo 2/complicaciones , Cabeza Femoral , Humanos , Microtomografía por Rayos X
13.
AACE Clin Case Rep ; 8(2): 58-64, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35415221

RESUMEN

Background: Camurati-Engelmann disease (CED) is a rare bone dysplasia characterized by diffuse diaphyseal osteosclerosis. Skull base involvement in CED can result in hypopituitarism but is seldom reported. Our objective was to report a patient with acquired hypopituitarism due to CED and assess the management challenges. Case Report: A 20-year-old boy presented with lower limb pain. He had walking difficulty in childhood, which was diagnosed as CED and managed with prednisolone. He later discontinued treatment and was lost to follow-up. Current re-evaluation showed short stature (-3.6 standard deviation), low weight (-4.3 standard deviation), and delayed puberty with delayed bone age (13 years). He was found to have secondary hypogonadism (luteinizing hormone level, 0.1 mIU/mL [1.7-8.6 mIU/mL]; follicle-stimulating hormone level, 1.0 mIU/mL [1.5-12.4 mIU/mL]; and testosterone level, 0.087 nmol/L [9-27 nmol/L]), growth hormone deficiency (low insulin-like growth factor I level, 120 ng/mL [226-903 ng/mL] and peak growth hormone level of 7 ng/mL on insulin-induced hypoglycemia), and secondary hypocortisolism (cortisol level, 105 nmol/L [170-550 nmol/L] and adrenocorticotropic hormone level, 6 pg/mL [5-65 pg/mL]). Serum prolactin level was normal (8.3 ng/mL [5-20 ng/mL]), and he was euthyroid on levothyroxine replacement. Magnetic resonance imaging revealed a partially empty sella. Sanger sequencing revealed a missense mutation (p.R218C/c.652C>T) in exon 4 of the TGFß1 gene. The patient was treated with zoledronate, losartan, and oral prednisolone and continued on levothyroxine and testosterone replacement, which resulted in symptomatic improvement. Discussion: The index case manifested severe CED requiring multimodality therapy. Later, he developed combined pituitary hormone deficiencies, which were managed with thyroid and gonadal hormone replacement with the continuation of glucocorticoids. The partial efficacy of bisphosphonates in CED has been reported in the literature. Conclusion: Skull base involvement in CED can lead to structural and functional hypopituitarism as a result of intracranial hypertension.

14.
J Bone Miner Res ; 37(10): 1860-1875, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35856247

RESUMEN

Primary hyperparathyroidism (PHPT) is third most common endocrine disorder characterized by hypercalcemia with elevated or nonsuppressed parathyroid hormone levels by parathyroid tumors. Familial PHPT, as part of multiple endocrine type-1, occurs due to the germline mutation in the MEN1 gene. The involvement and the role of germline MEN1 variations in sporadic PHPT of Indian PHPT patients are unknown. Precise classifications of different types of MEN1 variations are fundamental for determining clinical relevance and diagnostic role. This prospective cohort study was performed on 82 patients with PHPT (with no clinical or history of MEN1) who underwent screening for MEN1 variations through Sanger sequencing. Multilevel computational analysis was performed to determine the structure-function relationship of synonymous, nonsynonymous, and variants of uncertain significance (VUS). Of the 82 PHPT patients, 42 (51%) had 26 germline MEN1 variants, including eight nonsynonymous, seven synonymous, nine VUS, one splice site, and one regulatory variation. Five most common germline variations (c.1838A>G, c.1817C>T, c.1525C>A, c.-35A>T, and c.250T>C) were observed in this study. c.-35A>T (5' untranslated region [UTR]) was associated with recurrence of PHPT (odds ratio [OR] = 5.4; p = 0.04) and subsequent detection of other endocrine tumors (OR = 13.6, p = 0.035). c.1525C>A was associated with multi glandular parathyroid tumor (OR = 13.6, p = 0.035). Align-Grantham variation and Grantham deviation (Align-GVGD), functional analysis through hidden Markov MODEL (FATHMM), and MutationTaster analysis reported the disease-specific potential of VUS and synonymous variations. Significant linkage disequilibrium was observed in c.1785G>A and c.1817C>T (r2  = 0.3859, p = 0.0001), c.1475C>G and c.1525C>A (r2  = 0.385, p = 0.0004), and c.1569T>C and c.1838A>G (r2  = 0.488, p = 0.0001). The detection of MEN1 variations, especially those with disease-specific potential, can prompt early screening for other MEN1-related tumors and disease recurrence. © 2022 American Society for Bone and Mineral Research (ASBMR).


Asunto(s)
Hiperparatiroidismo Primario , Neoplasias de las Paratiroides , Humanos , Hiperparatiroidismo Primario/genética , Hiperparatiroidismo Primario/patología , Estudios Prospectivos , Regiones no Traducidas 5' , Recurrencia Local de Neoplasia/genética , Neoplasias de las Paratiroides/genética , Neoplasias de las Paratiroides/patología , Hormona Paratiroidea/genética , Células Germinativas/patología
15.
Med Eng Phys ; 93: 100-112, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34154770

RESUMEN

Bone fracture is a severe health concern; therefore, understanding the causes of bone fracture are crucial. This paper investigates the microstructure and fracture behaviour of cadaveric cortical bone of two different groups (Young, n= 6; Aged, n=7). The microstructure is obtained from µ-CT images, and the material parameters are measured with nanoindentation. Fracture behaviour in transverse and longitudinal orientations is investigated experimentally and numerically. The results show that the Haversian canal (HC) size increases and the osteon wall thickness (OWT) decreases significantly in the aged group, whereas a nonsignificant difference is found in tissue properties. The crack initiation (Jic) and crack growth (Jgrow) toughness of the aged group are found to be significantly lower (p<0.01) than the young group in the transverse orientation; however, for the longitudinal orientation, only the value of Jic in the aged group is found significantly lower. Further, a 4-phase XFEM (based on micro-CT image) model is developed to investigate the crack propagation behaviour in both orientations. For the transverse orientation, results show that in the aged group, the crack initially follows the cementline and then penetrates the osteon, whereas, in the young group, it propagates along the cementline. These results are in agreement with experimental results where the decrease in Jgrow is more significant than the Jic in the aged group. This study suggests that ageing leads to a larger HC and reduced OWT, which weakens the crack deflection ability and causes fragility fracture. Further, the XFEM results indicate that the presence of a small microcrack in the vicinity of a major crack tip causes an increase in the critical stress intensity factor.


Asunto(s)
Fracturas Óseas , Modelos Biológicos , Anciano , Envejecimiento , Hueso Cortical/diagnóstico por imagen , Análisis de Elementos Finitos , Fracturas Óseas/diagnóstico por imagen , Humanos
16.
J Biomech ; 123: 110495, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34004396

RESUMEN

Type-2 diabetic (T2D) and osteoporosis (OP) suffered patients are more prone to fragile fracture though the nature of alteration in areal bone mineral density (aBMD) in these two cases are completely different. Therefore, it becomes crucial to compare the effect of T2D and OP on alteration in mechanical and structural properties of femoral trabecular bone. This study investigated the effect of T2D, OP, and osteopenia on bone structural and mechanical properties using micro-CT, nanoindentation and compression test. Further, a nanoscale finite element model (FEM) was developed to predict the cause of alteration in mechanical properties. Finally, a damage-based FEM was proposed to predict the pathological related alteration of bone's mechanical response. The obtained results demonstrated that the T2D group had lower volume fraction (-18.25%, p = 0.023), young's modulus (-23.47%, p = 0.124), apparent modulus (-37.15%, p = 0.02), and toughness (-40%, p = 0.001) than the osteoporosis group. The damage-based FE results were found in good agreement with the compression experiment results for all three pathological conditions. Also, nanoscale FEM results demonstrated that the elastic and failure properties of mineralised collagen fibril decreases with increase in crystal size. This study reveals that T2D patients are more prone to fragile fracture in comparison to OP and osteopenia patients. Also, the proposed damage-based FEM can help to predict the risk of fragility fracture for different pathological conditions.


Asunto(s)
Hueso Esponjoso , Diabetes Mellitus Tipo 2 , Densidad Ósea , Hueso Esponjoso/diagnóstico por imagen , Diabetes Mellitus Tipo 2/complicaciones , Análisis de Elementos Finitos , Humanos , Estrés Mecánico
17.
J Clin Endocrinol Metab ; 106(5): e2271-e2289, 2021 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-33475711

RESUMEN

CONTEXT: Increased bone fragility and reduced energy absorption to fracture associated with type 2 diabetes (T2D) cannot be explained by bone mineral density alone. This study, for the first time, reports on alterations in bone tissue's material properties obtained from individuals with diabetes and known fragility fracture status. OBJECTIVE: To investigate the role of T2D in altering biomechanical, microstructural, and compositional properties of bone in individuals with fragility fracture. METHODS: Femoral head bone tissue specimens were collected from patients who underwent replacement surgery for fragility hip fracture. Trabecular bone quality parameters were compared in samples of 2 groups, nondiabetic (n = 40) and diabetic (n = 30), with a mean duration of disease 7.5 ± 2.8 years. RESULTS: No significant difference was observed in aBMD between the groups. Bone volume fraction (BV/TV) was lower in the diabetic group due to fewer and thinner trabeculae. The apparent-level toughness and postyield energy were lower in those with diabetes. Tissue-level (nanoindentation) modulus and hardness were lower in this group. Compositional differences in the diabetic group included lower mineral:matrix, wider mineral crystals, and bone collagen modifications-higher total fluorescent advanced glycation end-products (fAGEs), higher nonenzymatic cross-link ratio (NE-xLR), and altered secondary structure (amide bands). There was a strong inverse correlation between NE-xLR and postyield strain, fAGEs and postyield energy, and fAGEs and toughness. CONCLUSION: The current study is novel in examining bone tissue in T2D following first hip fragility fracture. Our findings provide evidence of hyperglycemia's detrimental effects on trabecular bone quality at multiple scales leading to lower energy absorption and toughness indicative of increased propensity to bone fragility.


Asunto(s)
Huesos/fisiología , Diabetes Mellitus Tipo 2/fisiopatología , Resistencia Flexional/fisiología , Anciano , Anciano de 80 o más Años , Fenómenos Biomecánicos/fisiología , Densidad Ósea/fisiología , Huesos/química , Huesos/patología , Huesos/ultraestructura , Hueso Esponjoso/fisiología , Hueso Esponjoso/ultraestructura , Estudios de Casos y Controles , Colágeno/análisis , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patología , Femenino , Productos Finales de Glicación Avanzada/análisis , Fracturas de Cadera/complicaciones , Fracturas de Cadera/metabolismo , Fracturas de Cadera/patología , Fracturas de Cadera/fisiopatología , Humanos , India , Masculino , Persona de Mediana Edad , Minerales/análisis
18.
Expert Opin Drug Deliv ; 17(2): 255-273, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31990219

RESUMEN

Background: The research work endeavors to develop a liquid dosage form of an efficacious antipsoriatic drug, i.e., coal tar, but having problems like variability and patient noncompliance.Methods: The emulsion was prepared by the wet gum method from standardized coal tar. The optimized lotion obtained after sequential experimental designs was characterized for various dosage form and/or coal tar-related properties including efficacy.Results: The formulation deposited more coal tar in the unit area of rat skin than marketed lotions. The efficacy of lotion in psoriasis animal models was more or equivalent to marketed lotions. The formulation showed one compartment body model dermatokinetics, nonirritancy after repeated applications, and stability at room conditions for a year.Conclusion: The formulation with desired attributes was successfully developed.


Asunto(s)
Alquitrán/administración & dosificación , Fármacos Dermatológicos/administración & dosificación , Psoriasis/tratamiento farmacológico , Crema para la Piel/administración & dosificación , Animales , Femenino , Masculino , Ratones Endogámicos BALB C , Ratas Sprague-Dawley
19.
Bone Rep ; 12: 100245, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32025536

RESUMEN

INTRODUCTION: Spondylo-epi-metaphyseal dysplasia (SEMD) represents a group of osteo-chondrodysplasias characterized by vertebral, epiphyseal as well as metaphyseal abnormalities. Several genes have been identified underlying the different forms. METHODOLOGY AND RESULTS: Two relatives (cousins) in a family were found to have disproportionate short stature with clinical and radiological features suggestive of SEMD. Metabolic bone profile was normal including parathyroid hormone and 25(OH)vitamin D3. Exome sequencing revealed a missense mutation (p. T120M) in the von-Willebrand factor A-domain of the Matrilin 3 (MATN3) gene that segregates with the disease in the family. CONCLUSION: We identified a homozygous missense mutation in MATN3, an important structural component of the extracellular matrix of cartilage, as the genetic cause of SEMD in this pedigree. MATN3 mutations have been more commonly associated with multiple epiphyseal dysplasia than SEMD. Recognition of this mutation will aid in enhancing the understanding and expanding the spectrum of this particular skeletal dysplasia.

20.
Bone Rep ; 12: 100247, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32025537

RESUMEN

Hypophosphatasia is an inborn error in metabolism characterized by low serum alkaline phosphatase (ALP) activity resulting from deactivating mutations in TNSALP (also known as ALPL), the gene that encodes the 'tissue-specific' isoenzyme of ALP. The disease exhibits significant clinical heterogeneity that spans from death in utero to only dental complications in adult life. Herein, we report a 47-year-old woman presenting with fracture of shaft of left femur. She had been complaining of pain in both of her thighs for the past 3 years. In addition, she gave a history of premature loss of teeth. Review of old radiographs revealed pseudo-fractures involving the lateral cortices of the femora on both sides. Biochemical panel revealed hyperphosphatemia, persistently low total alkaline phosphatase (ALP) and low-normal bone turnover markers. Screening of her siblings revealed low ALP in her younger sister and brother who were otherwise free from any major dento-arthro-osseous complaints. Sanger sequencing showed a novel, heterozygous, missense mutation in exon 5 at position 311 (c.311a > g;p.104 Asn > Ser) of ALPL gene in the three members. The patient underwent open reduction and intramedullary nailing of left femur along with prophylactic nailing on right side. This case report represents the first genetically confirmed kindred of adult hypophosphatasia from the Indian subcontinent.

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