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1.
Diabet Med ; 32(2): 267-73, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25251588

RESUMEN

AIMS: To assess markers of inflammation and bone turnover at presentation and at resolution of Charcot osteoarthropathy. METHODS: We measured serum inflammatory and bone turnover markers in a cross-sectional study of 35 people with Charcot osteoarthropathy, together with 34 people with diabetes and 12 people without diabetes. In addition, a prospective study of the subjects with Charcot osteoarthropathy was conducted until clinical resolution. RESULTS: At presentation, C-reactive protein (P = 0.007), tumour necrosis factor-α (P = 0.010) and interleukin-6 (P = 0.002), but not interleukin-1ß, (P = 0.254) were significantly higher in people with Charcot osteoarthropathy than in people with and without diabetes. Serum C-terminal telopeptide (P = 0.004), bone alkaline phosphatase (P = 0.006) and osteoprotegerin (P < 0.001), but not tartrate-resistant acid phosphatase (P = 0.126) and soluble receptor activator of nuclear factor-κß ligand (P = 0.915), were significantly higher in people with Charcot osteoarthropathy than in people with and without diabetes. At follow-up it was found that tumour necrosis factor-α (P = 0.012) and interleukin-6 (P = 0.003), but not C-reactive protein (P = 0.101), interleukin-1ß (P = 0.457), C-terminal telopeptide (P = 0.743), bone alkaline phosphatase (P = 0.193), tartrate-resistant acid phosphatase (P = 0.856), osteoprotegerin (P = 0.372) or soluble receptor activator of nuclear factor-kß ligand (P = 0.889), had significantly decreased between presentation and the 3 months of casting therapy time point, and all analytes remained unchanged from 3 months of casting therapy until resolution. In people with Charcot osteoarthropathy, there was a positive correlation between interleukin-6 and C-terminal telopeptide (P = 0.028) and tumour necrosis factor-α and C-terminal telopeptide (P = 0.013) only at presentation. CONCLUSIONS: At the onset of acute Charcot foot, serum concentrations of tumour necrosis factor-α and interleukin-6 were elevated; however, there was a significant reduction in these markers at resolution and these markers may be useful in the assessment of disease activity.


Asunto(s)
Artropatía Neurógena/terapia , Resorción Ósea/prevención & control , Colágeno Tipo I/sangre , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Regulación hacia Abajo , Interleucina-6/sangre , Péptidos/sangre , Adulto , Anciano , Artropatía Neurógena/sangre , Artropatía Neurógena/complicaciones , Artropatía Neurógena/fisiopatología , Biomarcadores/sangre , Resorción Ósea/etiología , Estudios de Cohortes , Estudios Transversales , Humanos , Inmovilización , Mediadores de Inflamación/sangre , Estudios Longitudinales , Persona de Mediana Edad , Estudios Prospectivos , Inducción de Remisión , Regulación hacia Arriba
2.
Rapid Commun Mass Spectrom ; 29(22): 2140-6, 2015 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-26467226

RESUMEN

RATIONALE: Following digestion of proteins with trypsin, digests are typically subjected to further 'clean-up' prior to liquid chromatography/mass spectometry (LC/MS) analysis, in order to reduce the complexity of the digested matrix, as well as helping to remove residual denaturants and reduction/alkylation reagents prior to injection onto the analytical HPLC column. Often, this is carried out using off-line techniques, and is not ideally suited to high-throughput workloads, for example in clinical laboratories. METHODS: Bovine serum albumin (BSA) was used as a model protein. Following denaturation with urea, reduction/alkylation, and digestion with trypsin, the analytical recovery of a selection of proteotypic BSA peptides was assessed using a two-dimensional, turbulent flow chromatography method. Peptides were identified using a Q Exactive™ mass spectometer operating in full-scan mode. RESULTS: Total analysis time (including the on-line sample clean-up) was 15 min per injection. Aside from the most hydrophilic peptide selected, ATEEQLK, recovery using the turbulent flow chromatography systems was greater than 30% for all remaining peptides (N = 17), and exceeded 50% for 12 of the 18 peptides studied. There was a broad correlation between the hydrophobicity factor and the observed recovery. CONCLUSIONS: This study suggests that turbulent flow chromatography offers a rapid, on-line alternative to solid-phase extraction for the analysis of peptide digests by LC/MS. A wide range of column chemistries are available, and the technique can be further optimised for analyses which are targetted to specific peptides. As with turbulent flow chromatography for small-molecule workflows, this approach may be ideally suited to high-throughput applications, such as those which are emerging from within clinical laboratories.


Asunto(s)
Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Fragmentos de Péptidos/análisis , Fragmentos de Péptidos/química , Secuencia de Aminoácidos , Animales , Bovinos , Cromatografía Liquida/instrumentación , Diseño de Equipo , Datos de Secuencia Molecular , Fragmentos de Péptidos/metabolismo , Albúmina Sérica Bovina , Tripsina/metabolismo
3.
Science ; 363(6425): 367-374, 2019 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-30538164

RESUMEN

In 2018, Kilauea Volcano experienced its largest lower East Rift Zone (LERZ) eruption and caldera collapse in at least 200 years. After collapse of the Pu'u 'O'o vent on 30 April, magma propagated downrift. Eruptive fissures opened in the LERZ on 3 May, eventually extending ~6.8 kilometers. A 4 May earthquake [moment magnitude (M w) 6.9] produced ~5 meters of fault slip. Lava erupted at rates exceeding 100 cubic meters per second, eventually covering 35.5 square kilometers. The summit magma system partially drained, producing minor explosions and near-daily collapses releasing energy equivalent to M w 4.7 to 5.4 earthquakes. Activity declined rapidly on 4 August. Summit collapse and lava flow volume estimates are roughly equivalent-about 0.8 cubic kilometers. Careful historical observation and monitoring of Kilauea enabled successful forecasting of hazardous events.

4.
Curr Med Res Opin ; 22(2): 405-15, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-16466613

RESUMEN

BACKGROUND: Many studies have investigated the prevalence of 25-hydroxy-vitamin D inadequacy throughout the world and found a high prevalence of 25-hydroxy-vitamin D inadequacy in older patients, particularly those with fragility fracture. SCOPE: To review the findings from vitamin D audits from six units across the UK and compare with previously published data from around the world. Results from four units have been previously published (Belfast, Glasgow, London and Medway) and this paper presents new data from Southampton and Carshalton, and further sub-analysis of the data from Medway. FINDINGS: Three audits of patients attending metabolic bone clinics (Carshalton, Medway and Southampton) identified 954 patients, of which overall 49% had a prior fragility fracture. Mean 25-hydroxy-vitamin D levels ranged from 47.7 nmol/L to 62.4 nmol/L. Of these patients 72.9-88.9% had a 25-hydroxy-vitamin D level < 80 nmol/L, 68.8-83.3% < 70 nmol/L and 37.5-59.1% < 50 nmol/L. The mean age of patients ranged from 60.0 to 67.5 years. Sub-analysis of the data by fracture status revealed that patients with fracture had lower mean levels of 25-hydroxy-vitamin D compared with patients without fracture. This was statistically significant in the sub-analysis of the Medway data (45.3 nmol/L versus 49.9 nmol/L, p < 0.005). Three audits identified 330 patients with fragility fracture. Audits from Glasgow and Belfast specifically identified patients with fragility fracture. A subgroup of patients with fracture aged over 50 years from the Medway audit was also included in this group. Mean levels of 25-hydroxy-vitamin D ranged from 40.0 nmol/L to 52.3 nmol/L. 83.7-96.4% of patients had a 25-hydroxy-vitamin D level < 80 nmol/L, 73.3-89.7% < 70 nmol/L and 55.8-73.2% < 50 nmol/L. The mean age of patients ranged from 65.3 to 68.6 years. The audits carried out in Belfast and Medway were also divided by supplementation status. Mean 25-hydroxy-vitamin D levels were 48.1 nmol/L in Belfast and 40.5 nmol/L in Medway in the patients not receiving supplements and 53.8 nmol/L and 59.9 nmol/L, respectively in the patients receiving supplements. The difference was statistically significant in the Medway audit (p < 0.0001), but not in the smaller Belfast audit (p = 0.216). As would be expected, the prevalence of 25-hydroxy-vitamin D inadequacy was higher in the patients not receiving supplements, for example at the 70 nmol/L threshold: 82.6% versus 67.1% in Belfast and 89.6% versus 72.7% in Medway. Three audits specifically identified 694 patients with hip fracture (Belfast, Glasgow and London). Mean levels of 25-hydroxy-vitamin D ranged from 24.7 nmol/L to 36.1 nmol/L. Of these patients 90.7-99.0% had a 25-hydroxy-vitamin D level < 80 nmol/L, 88.4-98.0% < 70 nmol/L and 81.6-92.7% < 50 nmol/L. The mean age of patients ranged from 73.4 to 80.5 years. CONCLUSION: Inadequate 25-hydroxy-vitamin D levels are extremely common in the elderly and particularly so in patients with fragility fracture - specifically in those with hip fracture. Although the differing audit specifications and assay techniques used make direct comparisons difficult, the data do provide a snapshot of 25-hydroxy-vitamin D status across the UK and are consistent with those previously observed elsewhere in Europe and the rest of the world.


Asunto(s)
Fracturas Óseas/complicaciones , Deficiencia de Vitamina D/epidemiología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Auditoría Médica , Prevalencia , Estudios Retrospectivos , Reino Unido/epidemiología , Deficiencia de Vitamina D/complicaciones
5.
Biochim Biophys Acta ; 1353(2): 98-102, 1997 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-9294001

RESUMEN

Human GATA-6 has been cloned from foetal heart by a combination of PCR-based methods and cDNA library screening. The 3.8 kbp cDNA has a coding sequence of 1347 bp the 449 aa protein is virtually identical in the two zinc-finger binding domains to other human GATA sequences, but varies considerably in the amino and carboxy terminal regions. The sequence shows greatest similarity to GATA-6-like sequences from rat, mouse, chicken and Xenopus. Northern analysis and in situ hybridisation show that GATA-6 is expressed at high levels in human adult and foetal heart as well as in gut derivatives. It is postulated that GATA-6, in concert with GATA-4, plays a crucial role in the regulation of cardiac differentiation.


Asunto(s)
ADN Complementario/biosíntesis , Proteínas de Unión al ADN/biosíntesis , Miocardio/metabolismo , Factores de Transcripción/biosíntesis , Secuencia de Aminoácidos , Secuencia de Bases , Clonación Molecular , Sistema Digestivo/metabolismo , Feto/metabolismo , Factor de Transcripción GATA6 , Expresión Génica , Biblioteca de Genes , Humanos , Hibridación in Situ , Datos de Secuencia Molecular
6.
Curr Med Res Opin ; 21(12): 1891-4, 2005 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16368037

RESUMEN

BACKGROUND: It is well established that vitamin D levels are suboptimal in the elderly and that adults with fragility fracture are more likely to have serum vitamin D levels either lower than those of control patients of similar age, or below the normal range. OBJECTIVES: To investigate the prevalence of vitamin D inadequacy in an elderly population with hip fractures from London (UK) and compare levels with data previously presented from Glasgow (UK). RESEARCH DESIGN AND METHODS: A retrospective patient audit was carried out over a 17-month period (September 2003-January 2005). Patient records were searched for hip fracture admissions and cross matched with vitamin D analysis carried out within 3 days of the hip fracture admission. The resulting records were hand searched to exclude patients with a hip fracture resulting from high impact/trauma. RESULTS: There were data for 103 hip fracture patients, 79.6% of the patients were women (n = 82). The mean age at the time of fracture was 73.4 years, 100% were aged 60 years or over and 41% were aged 75 years or over. Around 20% of the patients were receiving supplementation with calcium and/or vitamin D and were not excluded from the analysis. The mean vitamin D level was 32.1 nmol/L (12.9 ng/mL), SD = 19.4 (7.8), however, it is likely that the true mean is lower since in approximately 15% of cases vitamin D levels were reported as < 12.5 nmol/L, but were transcribed at 12.5 nmol/L in order to allow a numerical value to be calculated. Ninety-nine per cent of patients had a vitamin D level < 80 nmol/L, 94.2% < 70 nmol/L and 81.6% < 50 nmol/L. There were no significant differences by patient age or sex, however, there were significant seasonal differences in vitamin D. In the year from September 2003 to August 2004, 82.8% of summer admissions had vitamin D levels < 70 nmol/L compared with 98.0% in winter (p = 0.04). Mean vitamin D levels in the 30 patients with parathyroid hormone (PTH) levels above the reference range were significantly lower than levels in the 71 patients within the range: mean 19.9 nmol/L, SD = 16.2 versus mean 37.5 nmol/L, SD = 18.5 (p < 0.0001). Furthermore, 50% of the patients with PTH levels above the reference range had vitamin D levels < 12.5 nmol/L, reflecting extremely low levels of vitamin D. CONCLUSIONS: This study confirms almost universal vitamin D inadequacy among 103 patients admitted to hospital with hip fracture in London, although the prevalence of inadequacy is slightly lower than that seen in a similar study carried out in Glasgow.


Asunto(s)
Fracturas de Cadera/metabolismo , Osteoporosis/complicaciones , Deficiencia de Vitamina D/epidemiología , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/metabolismo , Hormona Paratiroidea/sangre , Prevalencia , Estudios Retrospectivos , Estaciones del Año , Factores Sexuales , Vitamina D/sangre
7.
Cardiovasc Res ; 27(7): 1204-8, 1993 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8252579

RESUMEN

OBJECTIVE: The aim was to investigate the expression of parathyroid hormone related peptide (PTHrP) gene in the human fetal and adult heart. METHODS: Molecular biological techniques were employed as well as immunocytochemistry and western blot analysis using rabbit polyclonal anti-PTHrP(1-34) and anti-PTHrP (56-86) on normal human fetal and adult heart tissues. Northern blot analysis of both normal human fetal and adult heart total RNA, using a human full length cDNA probe, and polymerase chain reaction analysis of normal human fetal and adult heart cDNAs with exon specific oligonucleotides were carried out. RESULTS: Positive staining was detected with both anti-PTHrP(1-34) and anti-PTHrP(56-86) in fetal heart at 12 weeks of gestation. In both fetal and adult hearts, multiple putative PTHrP proteins were observed with apparent molecular mass of 14-125 kDa. Multiple hybridising PTHrP mRNA isoforms (1.4, 2.1, 3.2, and 4.5 kb) were detected in both fetal and adult heart total RNAs. The fetal and adult heart cDNAs amplified from the cDNA libraries showed the presence of the 5' non-coding exon II and coding exons III-IV but not the 5' non-coding exon Ic. CONCLUSIONS: PTHrP is expressed in normal human fetal and adult hearts suggesting that it has a function as an endogenous modulator of the cardiovascular system.


Asunto(s)
Corazón/fisiología , Hormona Paratiroidea/genética , Proteínas/genética , Adulto , Northern Blotting , Western Blotting , Preescolar , Corazón Fetal/fisiología , Expresión Génica/fisiología , Humanos , Inmunohistoquímica , Pulmón/embriología , Proteína Relacionada con la Hormona Paratiroidea , Reacción en Cadena de la Polimerasa
8.
J Bone Miner Res ; 17(5): 891-7, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12009020

RESUMEN

Vitamin D and calcium supplementation significantly reduces the incidence of fractures. Evidence suggests vitamin D deficiency impairs neuromuscular function, causing an increase in falls and thereby fractures. The relationship between vitamin D, functional performance, and psychomotor function in elderly people who fall was examined in a prospective cross-sectional study. Patients were recruited from a falls clinic and stratified according to serum 25-hydroxyvitamin-D levels (25OHD): group 1, 25OHD < 12 microg/liter; group 2 25OHD, 12-17 microg/liter; and group 3, 25OHD > 17 microg/liter. Healthy elderly volunteers with 25OHD > 17 microg/liter comprised group 4 (n = 20/group). Measures included aggregate functional performance time (AFPT, seconds), isometric quadriceps strength (Newtons), postural sway (degrees), and choice reaction time (CRT, seconds). Serum bone biochemistry, 25OHD, and parathyroid hormone levels were measured. Patients who fell had significantly impaired functional performance, psychomotor function, and quadriceps strength compared with healthy subjects (AFPT: 51.0 s vs. 32.8 s,p < 0.05; CRT: 1.66 s vs. 0.98 s,p < 0.05; strength: 223N vs. 271N, t = 2.35, p = 0.02). Group 1 had significantly slower AFPT (66.0 s vs. 44.8 s, t = 4.15, p < 0.05) and CRT (2.37 s vs. 0.98 s, t = 3.59, p < 0.05) than groups 2 and 3. Group 1 had the greatest degree of postural sway and the weakest quadriceps strength, although this did not reach significance. Multivariate analysis revealed 25OHD as an independent variable for AFPT, CRT, and postural sway. PTH was an independent variable for muscle strength. Older people who fall have impaired functional performance, psychomotor function, and muscle strength. Within this group, those with 25OHD < 12 microg/liter are the most significantly affected.


Asunto(s)
Accidentes por Caídas , Calcifediol/sangre , Desempeño Psicomotor/fisiología , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Estudios Transversales , Humanos , Contracción Muscular/fisiología , Unión Neuromuscular/fisiopatología , Postura/fisiología , Estudios Prospectivos , Tiempo de Reacción/fisiología
9.
J Clin Endocrinol Metab ; 77(6): 1485-9, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7903311

RESUMEN

Familial isolated hyperparathyroidism (FIHP) is a rare heritable disorder characterized by hypercalcemia, inappropriately high PTH levels, and isolated parathyroid tumors with no evidence of hyperfunction of any other endocrine tissues. To establish whether FIHP exists as a distinct disease entity or represents a variant of any of the known multiple endocrine neoplasia (MEN) syndromes, we tested 19 members of a large, well characterized family with FIHP in which the disease is transmitted through 4 generations in an autosomal dominant fashion. Fourteen DNA markers at 10 polymorphic loci closely linked to the MEN1 locus on the long arm of chromosome 11 and 5 markers close to the MEN2A gene on chromosome 10 were tested using Southern blot analysis and polymerase chain reaction-based techniques. Additionally, two polymorphic markers (Mir1 and Mir2) within the prepro-PTH gene on the short arm of chromosome 11 were analyzed using denaturant gradient gel electrophoresis. Linkage was clearly excluded between FIHP and the MEN1 and MEN2A loci as well as to the PTH gene. Comparison of constitutional and tumor genotypes showed that constitutional heterozygosity was retained for markers in the MEN1 and MEN2A regions as well as to the PTH gene in 4 tumors from 3 affected members. In 1 individual, a parathyroid carcinoma was found after recurrence of hypercalcemia. We, therefore, propose that autosomal dominant FIHP can occur as a genetically and clinically distinct entity with an increased risk of malignant transformation of parathyroid tumors.


Asunto(s)
Hiperparatiroidismo/genética , Neoplasias de las Paratiroides/etiología , Adolescente , Adulto , Niño , Femenino , Ligamiento Genético , Humanos , Hiperparatiroidismo/complicaciones , Masculino , Persona de Mediana Edad , Neoplasia Endocrina Múltiple/genética , Hormona Paratiroidea/genética , Linaje , Riesgo
10.
Am J Clin Nutr ; 66(4): 937-43, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9322571

RESUMEN

Calcium intake and physical activity level (PAL) were assessed by questionnaire in 124 healthy women aged 52-62 y to determine the effect of calcium intake and PAL on bone mass and turnover. Four groups were identified according to their different reported calcium intakes and PALs. Bone mineral density (BMD) at the spine, hip, and left os calcis was measured together with total bone mineral content (TBMC) with dual-energy X-ray absorptiometry. Bone formation and resorption biochemical markers were measured in fasting samples of blood and urine. Women with the highest calcium intakes and PALs had the highest BMD at all sites compared with those with the lowest calcium intakes and PALs (P < 0.001). Calcium intake and PAL were positively correlated with BMD at all sites. Bone turnover markers did not explain the variation in bone mass between groups. In stepwise-multiple-regression analysis only calcium intake, physical activity, age, or weight remained as independent predictors of BMD and TBMC. When subjects were divided by past PALs, calcium intake and PAL were second to age and weight in their influence on spinal and hip BMD, but remained influential on the os calcis and whole body. We conclude that current high calcium intakes and PALs influence BMD at the os calcis and TBMC and protect bone mass in women 5-12 y postmenopausal at all measured sites, including the spine and hip. This finding does not exclude the possibility of past influences of calcium and activity on bone mass.


Asunto(s)
Densidad Ósea , Calcio de la Dieta/administración & dosificación , Aptitud Física , Posmenopausia/fisiología , Biomarcadores/sangre , Biomarcadores/orina , Calcio de la Dieta/metabolismo , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad , Osteoporosis/prevención & control , Posmenopausia/sangre , Posmenopausia/orina , Análisis de Regresión , Encuestas y Cuestionarios
11.
Bone ; 29(3): 209-15, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11557363

RESUMEN

We report the development of an assay for measurement of the urinary concentration of collagen type II C-telopeptide fragments. This assay was developed for providing a specific marker of joint metabolism. A monoclonal antibody, recognizing a linear six amino acid epitope from the middle region of the collagen type II C-telopeptide was used in a competitive enzyme-linked immunoassay (ELISA) format for measurement of urine samples. The technical performance and specificity of the assay was evaluated and a panel of samples from patients with rheumatoid arthritis (RA) (n = 27), osteoarthritis (OA) (n = 29), Paget's disease (n = 9), and healthy controls (n = 428) was measured in the assay. The ELISA was specific for the peptide EKGPDP derived from collagen type II C-telopeptide: it did not recognize peptides from the N-telopeptide of the molecule or from other collagen types. Collagen type II C-telopeptide fragments measured in the assay resisted seven freeze-thaw cycles and >20 h of storage at room temperature. RA and OA patients showed significant 2.33-fold (95% confidence interval [CI] 1.50-3.16) and 1.53-fold (CI 1.24-1.82) elevations in CartiLaps concentration, respectively. Paget's disease patients did not have elevated CartiLaps levels. RA patients with radiological evidence of cartilage damage had significantly higher (1.79-fold, CI 1.04-2.54) CartiLaps levels than RA patients without radiological evidence of cartilage destruction. The Cartilaps assay showed high technical precision and an ability to differentiate populations with an elevated joint metabolism from normal controls. This suggests that the assay may have clinical value in assisting in the diagnosis of joint diseases and in monitoring progression and therapy in RA and OA.


Asunto(s)
Artritis Reumatoide/orina , Cartílago/patología , Colágeno Tipo II/análisis , Osteoartritis/orina , Animales , Anticuerpos Monoclonales , Especificidad de Anticuerpos , Artritis Reumatoide/patología , Biomarcadores , Células Cultivadas , Ritmo Circadiano , Colágeno/análisis , Colágeno/inmunología , Colágeno/orina , Colágeno Tipo I , Colágeno Tipo II/inmunología , Colágeno Tipo II/orina , Ensayo de Inmunoadsorción Enzimática , Femenino , Técnicas In Vitro , Ratones , Ratones Endogámicos BALB C , Osteítis Deformante/patología , Osteítis Deformante/orina , Osteoartritis/patología , Osteoclastos/química , Osteoclastos/citología , Fragmentos de Péptidos/análisis , Fragmentos de Péptidos/inmunología , Fragmentos de Péptidos/orina , Péptidos/análisis , Péptidos/inmunología , Péptidos/orina , Conejos
12.
Bone ; 33(4): 549-56, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14555258

RESUMEN

The objective of the study was to investigate bone strength at four different skeletal sites in a chronic animal model of urinary diversion. Young male Wistar rats (120) were allocated randomly to four groups undergoing ileocystoplasty; ileocystoplasty and resection of the ileocecal segment; colocystoplasty; or sham operation (controls). After 8 months the lumbar vertebrae, femora, and tibiae were harvested at necropsy. Bone strength was assessed biomechanically at four different skeletal sites: vertebra L3, femoral middiaphysis, femoral neck, and distal femoral metaphysis. Bone mass and architecture were assessed using standard static histomorphometry of the proximal tibial metaphysis (trabecular bone volume [BV/TV]; trabecular number [Tb.N]) and ash weight. Statistically significant differences of biomechanical parameters between groups were observed at three skeletal sites with corresponding changes in tibial histomorphometry. Isolated ileocystoplasty resulted in decreased maximum load values of L3 (-16.4%; p < 0.0035) and a substantial reduction in tibial BV/TV (-34.7%; p < 0.05). Ileocystoplasty combined with resection of the ileocecal segment led to a significant loss of bone strength of L3 (-32.4%; p < 0.0015) and a dramatic reduction of tibial BV/TV (-45.9%; p < 0.01). Loss of tibial metaphyseal bone mass was predominantly caused by a decrease in Tb.N. (p < 0.01). Colonic augmentation had no significant effect on bone strength or histomorphometric values. In conclusion, this is the first experimental study to demonstrate the relevance of histomorphometrically proven bone loss after enterocystoplasty in terms of biomechanical variables.


Asunto(s)
Huesos/fisiología , Derivación Urinaria/efectos adversos , Acidosis/complicaciones , Animales , Fenómenos Biomecánicos , Densidad Ósea , Masculino , Osteoporosis/etiología , Ratas , Ratas Wistar , Derivación Urinaria/métodos
13.
Eur J Cancer ; 29A(1): 15-21, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1445735

RESUMEN

A total of 153 breast cancer patients who participated in two trials of adjuvant tamoxifen and who had not recurred were recruited into a study of the long term effects of tamoxifen. There were 60 controls (no tamoxifen), 73 ex-users (mostly for 2 years) and 20 current users (median treatment duration 72 months) and the median follow-up time was 7 years. A wide ranging study of lipids, hormones, bone density and haemostasis was undertaken. When compared with controls, current users had lower cholesterol levels (especially low density cholesterol), and increased triglyceride levels. Thyroid hormones were higher and sex hormone binding globulin was almost doubled. Bone density was non-significantly higher, clotting times were slightly shorter and fibrinogen and antithrombin III levels were reduced. However few of these changes persisted in ex-users, suggesting that most of the biological effects of treatment are reversible on cessation of treatment. This is reassuring for potentially negative side-effects, but also indicates that potentially positive 'side-effects' such as cholesterol lowering only occur while on active treatment.


Asunto(s)
Neoplasias de la Mama/sangre , Tamoxifeno/farmacología , Densidad Ósea/efectos de los fármacos , Neoplasias de la Mama/tratamiento farmacológico , Colesterol/sangre , Femenino , Estudios de Seguimiento , Glicéridos/sangre , Hemostasis , Humanos , Cuidados a Largo Plazo , Globulina de Unión a Hormona Sexual/metabolismo , Tamoxifeno/uso terapéutico , Hormonas Tiroideas/sangre
14.
J Mol Endocrinol ; 5(3): 259-66, 1990 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-2288637

RESUMEN

Parathyroid hormone-related peptide (PTHrP) has been detected in fetal serum and amniotic fluid. Using a combination of immunocytochemistry and molecular biology we have detected the peptide and its mRNA in a variety of fetal tissues throughout gestation. Tissue-specific mRNA isoforms were observed, the pattern of hybridization of which changed throughout gestation. In addition, the intensity and pattern of immunocytochemical localization of the peptide was found to vary over the time-period studied (8-30 weeks). PTHrP is expressed by a variety of tumours associated with the syndrome of humoral hypercalcaemia of malignancy and probably accounts for the hypercalcaemia by virtue of its limited amino acid homology with parathyroid hormone. These data demonstrate for the first time that PTHrP, a tumour-related peptide, is expressed during normal human fetal development, and suggest the possibility that it may function to regulate fetal calcium balance and growth in utero.


Asunto(s)
Líquido Amniótico/química , Desarrollo Embrionario y Fetal , Sangre Fetal/química , Proteínas/análisis , Bioensayo , Calcio/metabolismo , Sondas de ADN , Feto/química , Edad Gestacional , Humanos , Hipercalcemia/metabolismo , Técnicas para Inmunoenzimas , Hormona Paratiroidea/biosíntesis , Proteína Relacionada con la Hormona Paratiroidea , Placenta/química , Proteínas/genética , Proteínas/fisiología , ARN Mensajero/análisis , Células Tumorales Cultivadas/química
15.
Am J Med ; 109(4): 267-76, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10996576

RESUMEN

PURPOSE: We conducted a 5-year, double-blind, randomized, placebo-controlled study to determine whether salmon calcitonin nasal spray reduced the risk of new vertebral fractures in postmenopausal women with osteoporosis. SUBJECTS AND METHODS: A total of 1,255 postmenopausal women with established osteoporosis were randomly assigned to receive salmon calcitonin nasal spray (100, 200, or 400 IU) or placebo daily. All participants received elemental calcium (1,000 mg) and vitamin D (400 IU) daily. Vertebral fractures were assessed with lateral radiographs of the spine. The primary efficacy endpoint was the risk of new vertebral fractures in the salmon calcitonin nasal spray 200-IU group compared with the placebo group. RESULTS: During 5 years, 1,108 participants had at least one follow-up radiograph. A total of 783 women completed 3 years of treatment, and 511 completed 5 years. The 200-IU dose of salmon calcitonin nasal spray significantly reduced the risk of new vertebral fractures by 33% compared with placebo [200 IU: 51 of 287, placebo: 70 of 270, relative risk (RR) = 0.67, 95% confidence interval (CI): 0.47- to 0.97, P = 0.03]. In the 817 women with one to five prevalent vertebral fractures at enrollment, the risk was reduced by 36% (RR = 0.64, 95% CI: 0.43- to 0.96, P = 0.03). The reductions in vertebral fractures in the 100-IU (RR = 0.85, 95% CI: 0.60- to 1.21) and the 400-IU (RR = 0.84, 95% CI: 0.59- to 1.18) groups were not significantly different from placebo. Lumbar spine bone mineral density increased significantly from baseline (1% to 1. 5%, P<0.01) in all active treatment groups. Bone turnover was inhibited, as shown by suppression of serum type-I collagen cross-linked telopeptide (C-telopeptide) by 12% in the 200-IU group (P <0.01) and by 14% in the 400-IU group (P<0.01) as compared with placebo. CONCLUSION: Salmon calcitonin nasal spray at a dose of 200 IU daily significantly reduces the risk of new vertebral fractures in postmenopausal women with osteoporosis.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Calcitonina/administración & dosificación , Fracturas Espontáneas/prevención & control , Osteoporosis Posmenopáusica/tratamiento farmacológico , Fracturas de la Columna Vertebral/prevención & control , Anciano , Análisis de Varianza , Distribución de Chi-Cuadrado , Método Doble Ciego , Femenino , Fracturas Espontáneas/epidemiología , Fracturas Espontáneas/etiología , Humanos , Persona de Mediana Edad , Cavidad Nasal , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/diagnóstico , Valores de Referencia , Prevención Secundaria , Fracturas de la Columna Vertebral/epidemiología , Fracturas de la Columna Vertebral/etiología , Resultado del Tratamiento
16.
J Endocrinol ; 124(2): 319-25, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-2313219

RESUMEN

A radioimmunoassay based on an antiserum to human parathyroid hormone-related protein PTHrP(1-16) was used with PTHrP(1-34) standard to measure the concentration of immunoreactive PTHrP in extracts of fetal parathyroid glands from lambs and calves and also placental membranes obtained from several species, including man. Dilution curves from these sources were parallel to those obtained for PTHrP(1-34) standard. It was demonstrated that this parallelism was not the result of tracer damage caused by enzymic activity in the tissue extracts. Extracts of human placental membranes were subjected to high-pressure liquid chromatography with a linear acetonitrile gradient. Co-elution of cytochemical biological activity with 125I-labelled PTHrP(1-34) was noted. These results provide further evidence for both the fetal parathyroid glands and the placenta containing material resembling PTHrP which may be responsible for sustaining the activity of the placental calcium pump which maintains the fetus hypercalcaemic relative to its mother.


Asunto(s)
Membranas Extraembrionarias/análisis , Glándulas Paratiroides/análisis , Hormona Paratiroidea/análisis , Proteínas/análisis , Animales , Bovinos , Cromatografía Líquida de Alta Presión/métodos , Femenino , Humanos , Glándulas Paratiroides/embriología , Proteína Relacionada con la Hormona Paratiroidea , Radioinmunoensayo/métodos , Ovinos
17.
Mol Cell Endocrinol ; 69(2-3): R13-7, 1990 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-2184058

RESUMEN

Using a polyclonal antiserum raised against the first 34 amino acids of human parathyroid hormone-related peptide (PTHrP), we have localized PTHrP throughout the uro-genital tract of the human fetus aged between 8 and 40 weeks. Staining was present in the developing mesonephros, metanephros, gonads and in both the adrenal cortex and medulla. In particular, the developing mesonephric and metanephric renal tubules were intensely positive. Using Northern hybridization analysis we have detected a complex pattern of PTHrP mRNA transcripts ranging in size from 1.4 to 4.5 kb in early second trimester human fetal kidney. The presence of PTHrP in the mesonephros and metanephros provides evidence for a role for PTHrP in the regulation of fetal calcium metabolism. However, its presence in the gonad and adrenal gland invites the possibility of a wider role for PTHrP.


Asunto(s)
Proteínas de Neoplasias/análisis , Proteína Relacionada con la Hormona Paratiroidea , Fragmentos de Péptidos/análisis , Proteínas , Sistema Urogenital/embriología , Glándulas Suprarrenales/análisis , Glándulas Suprarrenales/embriología , Edad Gestacional , Gónadas/análisis , Gónadas/embriología , Humanos , Técnicas para Inmunoenzimas , Riñón/análisis , Riñón/embriología , Mesonefro/análisis , Proteínas de Neoplasias/genética , Hibridación de Ácido Nucleico , Fragmentos de Péptidos/genética , ARN Mensajero/análisis , Sistema Urogenital/análisis
18.
Aliment Pharmacol Ther ; 19(10): 1063-71, 2004 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-15142195

RESUMEN

BACKGROUND: Crohn's disease is associated with reduced bone density. The power of simple markers of systemic inflammation to identify higher rates of bone loss, in Crohn's disease, is uncertain. This relationship and the role of circulating (peripheral blood) mononuclear cells were investigated in a case-control study. METHODS: Urinary deoxypyridinoline/creatinine and serum osteocalcin concentrations were compared in male and premenopausal females with "active" Crohn's disease (C-reactive protein > or = 10 and/or erythrocyte sedimentation rate > or = 20) (n = 22) and controls with "quiescent" Crohn's disease (C-reactive protein < 10 and erythrocyte sedimentation rate < 20) (n = 21). No patients were receiving corticosteroid therapy. Production of tumour necrosis factor-alpha, interferon-gamma and prostaglandin E(2) by peripheral blood mononuclear cells were measured. RESULTS: Active Crohn's disease was associated with a higher deoxypyridinoline/creatinine (P = 0.02) and deoxypyridinoline/creatinine:osteocalcin ratio (P =0.01) compared with quiescent Crohn's disease, but similar osteocalcin (P = 0.24). These were not explained by vitamin D status, dietary intake or nutritional status. However, production of interferon-gamma by concanavalin A-stimulated peripheral blood mononuclear cells was lower in active Crohn's disease (P = 0.02) and correlated negatively with the deoxypyridinoline/creatinine:osteocalcin ratio (r = -0.40, P = 0.004). CONCLUSION: In Crohn's disease, raised C-reactive protein and erythrocyte sedimentation rate may indicate higher rates of bone loss and, if persistent, the need to assess bone mass even where disease symptoms are mild. This may be partly explained by altered production of interferon-gamma by peripheral blood mononuclear cells.


Asunto(s)
Remodelación Ósea/fisiología , Proteína C-Reactiva/análisis , Enfermedad de Crohn/fisiopatología , Adulto , Sedimentación Sanguínea , Resorción Ósea/fisiopatología , Estudios de Casos y Controles , Citocinas/metabolismo , Femenino , Humanos , Masculino , Estado Nutricional , Osteocalcina/metabolismo , Prostaglandinas/metabolismo
19.
Aliment Pharmacol Ther ; 19(5): 563-70, 2004 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-14987325

RESUMEN

BACKGROUND: Retrospective studies have suggested that hormone replacement therapy may reduce the rate of bone loss in primary biliary cirrhosis, but no controlled data are available. METHODS: Forty-two post-menopausal women with primary biliary cirrhosis were treated with calcium and vitamin D, either alone (n = 21) or together with transdermal hormone replacement therapy (n = 21). Bone densitometry was performed at baseline and at 1 year, and serum and urinary markers of bone turnover were measured at three-monthly intervals. RESULTS: At entry, 17 patients (40%) had spinal or femoral osteopenia (T score - 1 to - 2.5) and nine (21%) had osteoporosis (T < - 2.5). In those given hormone replacement therapy, there was a significant decrease in the mean urinary deoxypyridinoline :creatinine ratios at 3 months (7.8 vs. 6.1 nm/mm creatinine for no hormone replacement therapy vs. hormone replacement therapy; P = 0.04) and a 48% reduction in urinary calcium excretion at 1 year (0.66 vs. 0.32 mm/mm creatinine; P = 0.01). Repeat bone densitometry at 1 year revealed a 2.25% increase in the hormone replacement therapy group (P = 0.02), compared with a non-significant 0.87% decrease in L2-L4 bone mineral density in those not given hormone replacement therapy. Both treatment regimens were well tolerated, with no increase in cholestasis. CONCLUSIONS: Compared with calcium and vitamin D alone, supplemental treatment with transdermal hormone replacement therapy for 1 year improved the vertebral bone density and urinary markers of bone turnover in post-menopausal women with primary biliary cirrhosis.


Asunto(s)
Densidad Ósea/efectos de los fármacos , Terapia de Reemplazo de Hormonas/métodos , Cirrosis Hepática Biliar/tratamiento farmacológico , Administración Cutánea , Anciano , Aminoácidos/orina , Remodelación Ósea/efectos de los fármacos , Femenino , Terapia de Reemplazo de Hormonas/efectos adversos , Humanos , Cirrosis Hepática Biliar/fisiopatología , Persona de Mediana Edad , Estudios Prospectivos
20.
Aliment Pharmacol Ther ; 16(11): 1895-902, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12390098

RESUMEN

AIM: To establish whether bone disease is present at diagnosis in inflammatory bowel disease and to identify contributory metabolic abnormalities. METHODS: Newly diagnosed patients with inflammatory bowel disease (19 males, 15 females; mean age, 44 years; range, 17-79 years; 23 ulcerative colitis, 11 Crohn's disease) were compared against standard reference ranges and a control group with irritable bowel syndrome (eight males, 10 females; mean age, 40 years; range, 19-64 years). Bone mineral density (g/cm2, dual-energy X-ray absorptiometry: lumbar spine and femoral neck) and biochemical bone markers were measured. RESULTS: Femoral neck bone mineral density, T- and Z-scores (mean +/- s.d., respectively) were lower in inflammatory bowel disease patients than in irritable bowel syndrome controls (0.78 +/- 0.12 vs. 0.90 +/- 0.16, P = 0.0046; - 0.88 +/- 0.92 vs. 0.12 +/- 1.17, P = 0.0018; - 0.30 +/- 0.89 vs. 0.61 +/- 1.10, P = 0.0030). Lumbar spine bone mineral density and T-scores were also significantly lower in patients than controls (0.98 +/- 0.15 vs. 1.08 +/- 0.13, P = 0.0342; - 1.05 +/- 1.39 vs. - 0.14 +/- 1.19, P = 0.0304). Compared with controls, the urinary deoxypyridinoline : creatinine ratio was increased (7.66 vs. 5.70 nmol/mmol, P = 0.0163) and serum 25-hydroxy vitamin D was decreased (18.7 vs. 28.5 micro g/L, P = 0.0016); plasma osteocalcin and serum parathyroid hormone did not differ (P > 0.05). CONCLUSIONS: The bone mineral density is reduced at diagnosis, prior to corticosteroid treatment, in both Crohn's disease and ulcerative colitis. Our data suggest that this is attributable to increased resorption rather than decreased bone formation.


Asunto(s)
Enfermedades Óseas Metabólicas/etiología , Enfermedades Inflamatorias del Intestino/complicaciones , Adolescente , Adulto , Anciano , Biomarcadores/análisis , Densidad Ósea , Enfermedades Óseas Metabólicas/fisiopatología , Estudios de Casos y Controles , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/fisiopatología , Enfermedades Funcionales del Colon/complicaciones , Enfermedades Funcionales del Colon/fisiopatología , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/fisiopatología , Femenino , Cuello Femoral/fisiopatología , Humanos , Enfermedades Inflamatorias del Intestino/fisiopatología , Vértebras Lumbares/fisiopatología , Masculino , Persona de Mediana Edad
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