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1.
Osteoporos Int ; 35(5): 919-927, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38507080

RESUMO

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.


Assuntos
Doenças Ósseas Metabólicas , Hipopituitarismo , Osteoporose , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Densidade Óssea , Osteoporose/diagnóstico por imagem , Hipopituitarismo/diagnóstico por imagem , Hipopituitarismo/tratamento farmacológico , Tomografia Computadorizada por Raios X , Tíbia/diagnóstico por imagem , Rádio (Anatomia) , Absorciometria de Fóton/métodos
2.
Calcif Tissue Int ; 104(5): 561-569, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31069441

RESUMO

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.


Assuntos
Doenças Ósseas Metabólicas/diagnóstico , Colágeno/metabolismo , Osteogênese Imperfeita/diagnóstico , Fosfatase Alcalina/sangue , Biópsia , Doenças Ósseas Metabólicas/complicações , Doenças Ósseas Metabólicas/terapia , Osso e Ossos/patologia , Difosfonatos/uso terapêutico , Progressão da Doença , Fraturas Ósseas/etiologia , Humanos , Melfalan/uso terapêutico , Mutação , Osteogênese Imperfeita/complicações , Osteogênese Imperfeita/terapia , Paraproteinemias/sangue , Prednisolona/uso terapêutico , Prognóstico , Cintilografia , Esteroides/uso terapêutico
3.
Calcif Tissue Int ; 94(2): 240-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24154985

RESUMO

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.


Assuntos
Síndrome de Camurati-Engelmann , Adolescente , Povo Asiático , Síndrome de Camurati-Engelmann/diagnóstico por imagem , Feminino , Humanos , Extremidade Inferior , Debilidade Muscular/diagnóstico por imagem , Mialgia/diagnóstico por imagem , Linhagem , Radiografia , Cintilografia , Imagem Corporal Total
5.
Indian J Med Res ; 140(1): 46-54, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25222777

RESUMO

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.


Assuntos
Difosfonatos/efeitos adversos , Difosfonatos/uso terapêutico , Fraturas do Fêmur/induzido quimicamente , Fraturas do Fêmur/diagnóstico por imagem , Osteoporose/tratamento farmacológico , Absorciometria de Fóton , Adulto , Idoso , Alendronato , Feminino , Humanos , Imidazóis , Índia , Pessoa de Meia-Idade , Osteoporose/diagnóstico por imagem , Sintomas Prodrômicos , Estudos Retrospectivos , Ácido Zoledrônico
6.
Diabetes Metab Syndr ; 18(8): 103109, 2024 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-39191163

RESUMO

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.
J Proteomics ; 302: 105200, 2024 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-38772440

RESUMO

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.


Assuntos
Biomarcadores , Diabetes Mellitus Tipo 2 , Metabolômica , Osteoporose Pós-Menopausa , Humanos , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Pessoa de Meia-Idade , Biomarcadores/sangue , Metabolômica/métodos , Osteoporose Pós-Menopausa/metabolismo , Osteoporose Pós-Menopausa/sangue , Osteoporose Pós-Menopausa/diagnóstico , Idoso , Espectroscopia de Ressonância Magnética/métodos , Metaboloma
8.
Arch Virol ; 158(11): 2359-63, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23685897

RESUMO

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.


Assuntos
Surtos de Doenças , Epidemiologia Molecular , Vírus da Caxumba/genética , Caxumba/epidemiologia , Caxumba/virologia , Anticorpos Antivirais/sangue , Criança , Feminino , Genótipo , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Índia/epidemiologia , Masculino , Tipagem Molecular , Vírus da Caxumba/classificação , Vírus da Caxumba/imunologia , Vírus da Caxumba/isolamento & purificação , Parotidite/epidemiologia , Parotidite/virologia , RNA Viral/sangue , RNA Viral/genética , RNA Viral/isolamento & purificação
9.
J Biomech ; 161: 111853, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37890220

RESUMO

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.


Assuntos
Osso e Ossos , Osso Cortical , Humanos , Pressão , Fadiga , Estresse Mecânico
10.
Bone ; 173: 116788, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37172883

RESUMO

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.


Assuntos
Fraturas Ósseas , Osteopetrose , Criança , Humanos , Osteopetrose/genética , Osteoclastos , Ácido Zoledrônico , Crânio
11.
Med Eng Phys ; 104: 103810, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35641076

RESUMO

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.


Assuntos
Diabetes Mellitus Tipo 2 , Fraturas do Quadril , Osso Esponjoso/diagnóstico por imagem , Osso Esponjoso/fisiologia , Diabetes Mellitus Tipo 2/complicações , Cabeça do Fêmur , Humanos , Microtomografia por Raio-X
12.
AACE Clin Case Rep ; 8(2): 58-64, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35415221

RESUMO

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.

13.
J Bone Miner Res ; 37(10): 1860-1875, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35856247

RESUMO

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).


Assuntos
Hiperparatireoidismo Primário , Neoplasias das Paratireoides , Humanos , Hiperparatireoidismo Primário/genética , Hiperparatireoidismo Primário/patologia , Estudos Prospectivos , Regiões 5' não Traduzidas , Recidiva Local de Neoplasia/genética , Neoplasias das Paratireoides/genética , Neoplasias das Paratireoides/patologia , Hormônio Paratireóideo/genética , Células Germinativas/patologia
14.
Med Eng Phys ; 93: 100-112, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34154770

RESUMO

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.


Assuntos
Fraturas Ósseas , Modelos Biológicos , Idoso , Envelhecimento , Osso Cortical/diagnóstico por imagem , Análise de Elementos Finitos , Fraturas Ósseas/diagnóstico por imagem , Humanos
15.
J Biomech ; 123: 110495, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34004396

RESUMO

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.


Assuntos
Osso Esponjoso , Diabetes Mellitus Tipo 2 , Densidade Óssea , Osso Esponjoso/diagnóstico por imagem , Diabetes Mellitus Tipo 2/complicações , Análise de Elementos Finitos , Humanos , Estresse Mecânico
16.
J Clin Endocrinol Metab ; 106(5): e2271-e2289, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33475711

RESUMO

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.


Assuntos
Osso e Ossos/fisiologia , Diabetes Mellitus Tipo 2/fisiopatologia , Resistência à Flexão/fisiologia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos/fisiologia , Densidade Óssea/fisiologia , Osso e Ossos/química , Osso e Ossos/patologia , Osso e Ossos/ultraestrutura , Osso Esponjoso/fisiologia , Osso Esponjoso/ultraestrutura , Estudos de Casos e Controles , Colágeno/análise , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Feminino , Produtos Finais de Glicação Avançada/análise , Fraturas do Quadril/complicações , Fraturas do Quadril/metabolismo , Fraturas do Quadril/patologia , Fraturas do Quadril/fisiopatologia , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Minerais/análise
17.
Expert Opin Drug Deliv ; 17(2): 255-273, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31990219

RESUMO

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.


Assuntos
Alcatrão/administração & dosagem , Fármacos Dermatológicos/administração & dosagem , Psoríase/tratamento farmacológico , Creme para a Pele/administração & dosagem , Animais , Feminino , Masculino , Camundongos Endogâmicos BALB C , Ratos Sprague-Dawley
18.
Bone Rep ; 12: 100245, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32025536

RESUMO

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.

19.
Bone Rep ; 12: 100247, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32025537

RESUMO

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.

20.
AACE Clin Case Rep ; 6(3): e105-e112, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32524022

RESUMO

OBJECTIVE: Hypophosphatemic rickets with hypercalciuria (HHRH) is a rare, recessively-inherited form of rickets caused by homozygous or compound heterozygous mutations in the SLC34A3 gene that encodes the renal tubular phosphate transporter protein NaPi2c. The bone phenotype varies from severe rickets to no disease. Accurate diagnosis is important as the treatment differs from other forms of rickets. METHODS: The patient was a 12-year-old boy from the Indian subcontinent with florid hypophosphatemic rickets. A targeted gene panel to search for mutations in genes associated with inherited forms of rickets was performed. We also completed a literature search of published cases of HHRH. RESULTS: The targeted gene panel demonstrated a novel homozygous SLC34A3 mutation: c.1339 G>A (p.Ala447Thr). His parents were heterozygous for the mutation. In our literature review we found that people with homozygous SLC34A3 mutations were more likely to have rickets than those with compound heterozygous mutations (85% versus 45%, p<0.002) and that serum phosphate z scores were lower in those with rickets than those without (-3.3 with a standard deviation of 1.5 versus -2.1 with a standard deviation of 1.5, p<0.005). CONCLUSION: The bone phenotype of HHRH is related to the nature of the mutation and serum phosphate levels. Targeted gene panels can aid in the accurate diagnosis of inherited forms of rickets, and facilitate correct treatment.

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